Cyclic AMIDES formed from aminocarboxylic acids by the elimination of water. Lactims are the enol forms of lactams.
A cyclohexylamido analog of PENICILLANIC ACID.
Four-membered cyclic AMIDES, best known for the PENICILLINS based on a bicyclo-thiazolidine, as well as the CEPHALOSPORINS based on a bicyclo-thiazine, and including monocyclic MONOBACTAMS. The BETA-LACTAMASES hydrolyze the beta lactam ring, accounting for BETA-LACTAM RESISTANCE of infective bacteria.
A frequent complication of drug therapy for microbial infection. It may result from opportunistic colonization following immunosuppression by the primary pathogen and can be influenced by the time interval between infections, microbial physiology, or host resistance. Experimental challenge and in vitro models are sometimes used in virulence and infectivity studies.
Substances that reduce the growth or reproduction of BACTERIA.
Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.
Nonsusceptibility of an organism to the action of penicillins.
Diminished or failed response of an organism, disease or tissue to the intended effectiveness of a chemical or drug. It should be differentiated from DRUG TOLERANCE which is the progressive diminution of the susceptibility of a human or animal to the effects of a drug, as a result of continued administration.
Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The ability of microorganisms, especially bacteria, to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
The ability of bacteria to resist or to become tolerant to chemotherapeutic agents, antimicrobial agents, or antibiotics. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
Works about clinical trials that involve at least one test treatment and one control treatment, concurrent enrollment and follow-up of the test- and control-treated groups, and in which the treatments to be administered are selected by a random process, such as the use of a random-numbers table.
Resistance or diminished response of a neoplasm to an antineoplastic agent in humans, animals, or cell or tissue cultures.
A 13-amino acid peptide derived from proteolytic cleavage of ADRENOCORTICOTROPIC HORMONE, the N-terminal segment of ACTH. ACTH (1-13) is amidated at the C-terminal to form ACTH (1-13)NH2 which in turn is acetylated to form alpha-MSH in the secretory granules. Alpha-MSH stimulates the synthesis and distribution of MELANIN in MELANOCYTES in mammals and MELANOPHORES in lower vertebrates.
A class of organic compounds containing a ring structure made up of more than one kind of atom, usually carbon plus another atom. The ring structure can be aromatic or nonaromatic.
Simultaneous resistance to several structurally and functionally distinct drugs.
An interleukin-1 subtype that is synthesized as an inactive membrane-bound pro-protein. Proteolytic processing of the precursor form by CASPASE 1 results in release of the active form of interleukin-1beta from the membrane.
Compounds consisting of glucosamine and lactate joined by an ether linkage. They occur naturally as N-acetyl derivatives in peptidoglycan, the characteristic polysaccharide composing bacterial cell walls. (From Dorland, 28th ed)
The capacity of an organism to defend itself against pathological processes or the agents of those processes. This most often involves innate immunity whereby the organism responds to pathogens in a generic way. The term disease resistance is used most frequently when referring to plants.
The force that opposes the flow of BLOOD through a vascular bed. It is equal to the difference in BLOOD PRESSURE across the vascular bed divided by the CARDIAC OUTPUT.
Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).
The ability of viruses to resist or to become tolerant to chemotherapeutic agents or antiviral agents. This resistance is acquired through gene mutation.
The ability of bacteria to resist or to become tolerant to several structurally and functionally distinct drugs simultaneously. This resistance may be acquired through gene mutation or foreign DNA in transmissible plasmids (R FACTORS).
The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)
The location of the atoms, groups or ions relative to one another in a molecule, as well as the number, type and location of covalent bonds.
An 11-kDa protein associated with the outer membrane of many cells including lymphocytes. It is the small subunit of the MHC class I molecule. Association with beta 2-microglobulin is generally required for the transport of class I heavy chains from the endoplasmic reticulum to the cell surface. Beta 2-microglobulin is present in small amounts in serum, csf, and urine of normal people, and to a much greater degree in the urine and plasma of patients with tubular proteinemia, renal failure, or kidney transplants.
The creation of an amine. It can be produced by the addition of an amino group to an organic compound or reduction of a nitro group.
A plant genus of the family CAPPARACEAE that contains cleogynol and 15alpha-acetoxycleomblynol (dammaranes) and 1-epibrachyacarpone (a triterpene), and ISOTHIOCYANATES.
A family of G-protein-coupled receptors that have specificity for MELANOCYTE-STIMULATING HORMONES and ADRENOCORTICOTROPIC HORMONE. There are several subtypes of melanocortin receptors, each having a distinct ligand specificity profile and tissue localization.
Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.
Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.
One of two major pharmacologically defined classes of adrenergic receptors. The beta adrenergic receptors play an important role in regulating CARDIAC MUSCLE contraction, SMOOTH MUSCLE relaxation, and GLYCOGENOLYSIS.
An integrin beta subunit of approximately 85-kDa in size which has been found in INTEGRIN ALPHAIIB-containing and INTEGRIN ALPHAV-containing heterodimers. Integrin beta3 occurs as three alternatively spliced isoforms, designated beta3A-C.
Nonsusceptibility of bacteria to the action of TETRACYCLINE which inhibits aminoacyl-tRNA binding to the 30S ribosomal subunit during protein synthesis.
Proteins found in any species of bacterium.
A group of antibiotic aminoglycosides differing only in the number of repeating residues in the peptide side chain. They are produced by Streptomyces and Actinomyces and may have broad spectrum antimicrobial and some antiviral properties.
Diseases of plants.
The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.
The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.
A group of often glycosylated macrocyclic compounds formed by chain extension of multiple PROPIONATES cyclized into a large (typically 12, 14, or 16)-membered lactone. Macrolides belong to the POLYKETIDES class of natural products, and many members exhibit ANTIBIOTIC properties.
Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow.
The ability of fungi to resist or to become tolerant to chemotherapeutic agents, antifungal agents, or antibiotics. This resistance may be acquired through gene mutation.
Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).
A genus of bacteria that form a nonfragmented aerial mycelium. Many species have been identified with some being pathogenic. This genus is responsible for producing a majority of the ANTI-BACTERIAL AGENTS of practical value.
A factor synthesized in a wide variety of tissues. It acts synergistically with TGF-alpha in inducing phenotypic transformation and can also act as a negative autocrine growth factor. TGF-beta has a potential role in embryonal development, cellular differentiation, hormone secretion, and immune function. TGF-beta is found mostly as homodimer forms of separate gene products TGF-beta1, TGF-beta2 or TGF-beta3. Heterodimers composed of TGF-beta1 and 2 (TGF-beta1.2) or of TGF-beta2 and 3 (TGF-beta2.3) have been isolated. The TGF-beta proteins are synthesized as precursor proteins.
Organic compounds containing the carboxy group (-COOH). This group of compounds includes amino acids and fatty acids. Carboxylic acids can be saturated, unsaturated, or aromatic.
A group of antibiotics that contain 6-aminopenicillanic acid with a side chain attached to the 6-amino group. The penicillin nucleus is the chief structural requirement for biological activity. The side-chain structure determines many of the antibacterial and pharmacological characteristics. (Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1065)
Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.
The molecular designing of drugs for specific purposes (such as DNA-binding, enzyme inhibition, anti-cancer efficacy, etc.) based on knowledge of molecular properties such as activity of functional groups, molecular geometry, and electronic structure, and also on information cataloged on analogous molecules. Drug design is generally computer-assisted molecular modeling and does not include pharmacokinetics, dosage analysis, or drug administration analysis.
Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)
The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.
Organic compounds containing the -CO-NH2 radical. Amides are derived from acids by replacement of -OH by -NH2 or from ammonia by the replacement of H by an acyl group. (From Grant & Hackh's Chemical Dictionary, 5th ed)
Nonsusceptibility of bacteria to the action of the beta-lactam antibiotics. Mechanisms responsible for beta-lactam resistance may be degradation of antibiotics by BETA-LACTAMASES, failure of antibiotics to penetrate, or low-affinity binding of antibiotics to targets.
Established cell cultures that have the potential to propagate indefinitely.
A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.
A type of strength-building exercise program that requires the body muscle to exert a force against some form of resistance, such as weight, stretch bands, water, or immovable objects. Resistance exercise is a combination of static and dynamic contractions involving shortening and lengthening of skeletal muscles.
Peptides whose amino and carboxy ends are linked together with a peptide bond forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS. Some of them are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).
A class of saturated compounds consisting of two rings only, having two or more atoms in common, containing at least one hetero atom, and that take the name of an open chain hydrocarbon containing the same total number of atoms. (From Riguady et al., Nomenclature of Organic Chemistry, 1979, p31)
RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.
The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.
The capacity of a normal organism to remain unaffected by microorganisms and their toxins. It results from the presence of naturally occurring ANTI-INFECTIVE AGENTS, constitutional factors such as BODY TEMPERATURE and immediate acting immune cells such as NATURAL KILLER CELLS.
An integrin found in FIBROBLASTS; PLATELETS; MONOCYTES, and LYMPHOCYTES. Integrin alpha5beta1 is the classical receptor for FIBRONECTIN, but it also functions as a receptor for LAMININ and several other EXTRACELLULAR MATRIX PROTEINS.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
Extrachromosomal, usually CIRCULAR DNA molecules that are self-replicating and transferable from one organism to another. They are found in a variety of bacterial, archaeal, fungal, algal, and plant species. They are used in GENETIC ENGINEERING as CLONING VECTORS.
A class of plasmids that transfer antibiotic resistance from one bacterium to another by conjugation.
Also known as CD104 antigen, this protein is distinguished from other beta integrins by its relatively long cytoplasmic domain (approximately 1000 amino acids vs. approximately 50). Five alternatively spliced isoforms have been described.
An analytical technique for resolution of a chemical mixture into its component compounds. Compounds are separated on an adsorbent paper (stationary phase) by their varied degree of solubility/mobility in the eluting solvent (mobile phase).
Deoxyribonucleic acid that makes up the genetic material of bacteria.
A 51-amino acid pancreatic hormone that plays a major role in the regulation of glucose metabolism, directly by suppressing endogenous glucose production (GLYCOGENOLYSIS; GLUCONEOGENESIS) and indirectly by suppressing GLUCAGON secretion and LIPOLYSIS. Native insulin is a globular protein comprised of a zinc-coordinated hexamer. Each insulin monomer containing two chains, A (21 residues) and B (30 residues), linked by two disulfide bonds. Insulin is used as a drug to control insulin-dependent diabetes mellitus (DIABETES MELLITUS, TYPE 1).
This intrgrin is a key component of HEMIDESMOSOMES and is required for their formation and maintenance in epithelial cells. Integrin alpha6beta4 is also found on thymocytes, fibroblasts, and Schwann cells, where it functions as a laminin receptor (RECEPTORS, LAMININ) and is involved in wound healing, cell migration, and tumor invasiveness.
A group of broad-spectrum antibiotics first isolated from the Mediterranean fungus ACREMONIUM. They contain the beta-lactam moiety thia-azabicyclo-octenecarboxylic acid also called 7-aminocephalosporanic acid.
Integrin beta chains combine with integrin alpha chains to form heterodimeric cell surface receptors. Integrins have traditionally been classified into functional groups based on the identity of one of three beta chains present in the heterodimer. The beta chain is necessary and sufficient for integrin-dependent signaling. Its short cytoplasmic tail contains sequences critical for inside-out signaling.
A 170-kDa transmembrane glycoprotein from the superfamily of ATP-BINDING CASSETTE TRANSPORTERS. It serves as an ATP-dependent efflux pump for a variety of chemicals, including many ANTINEOPLASTIC AGENTS. Overexpression of this glycoprotein is associated with multidrug resistance (see DRUG RESISTANCE, MULTIPLE).
The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.
A cell line derived from cultured tumor cells.
A 44-kDa highly glycosylated plasma protein that binds phospholipids including CARDIOLIPIN; APOLIPOPROTEIN E RECEPTOR; membrane phospholipids, and other anionic phospholipid-containing moieties. It plays a role in coagulation and apoptotic processes. Formerly known as apolipoprotein H, it is an autoantigen in patients with ANTIPHOSPHOLIPID ANTIBODIES.
The characteristic three-dimensional shape of a molecule.
Nonsusceptibility of a microbe to the action of ampicillin, a penicillin derivative that interferes with cell wall synthesis.
Nonsusceptibility of bacteria to the action of CHLORAMPHENICOL, a potent inhibitor of protein synthesis in the 50S ribosomal subunit where amino acids are added to nascent bacterial polypeptides.
Elements of limited time intervals, contributing to particular results or situations.
In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.
Integrin alpha4beta1 is a FIBRONECTIN and VCAM-1 receptor present on LYMPHOCYTES; MONOCYTES; EOSINOPHILS; NK CELLS and thymocytes. It is involved in both cell-cell and cell- EXTRACELLULAR MATRIX adhesion and plays a role in INFLAMMATION, hematopoietic cell homing and immune function, and has been implicated in skeletal MYOGENESIS; NEURAL CREST migration and proliferation, lymphocyte maturation and morphogenesis of the PLACENTA and HEART.
Organic nitrogenous bases. Many alkaloids of medical importance occur in the animal and vegetable kingdoms, and some have been synthesized. (Grant & Hackh's Chemical Dictionary, 5th ed)
A naphthacene antibiotic that inhibits AMINO ACYL TRNA binding during protein synthesis.
Unstable isotopes of indium that decay or disintegrate emitting radiation. In atoms with atomic weights 106-112, 113m, 114, and 116-124 are radioactive indium isotopes.
The functional hereditary units of BACTERIA.
The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.
A subclass of beta-adrenergic receptors (RECEPTORS, ADRENERGIC, BETA). The adrenergic beta-2 receptors are more sensitive to EPINEPHRINE than to NOREPINEPHRINE and have a high affinity for the agonist TERBUTALINE. They are widespread, with clinically important roles in SKELETAL MUSCLE; LIVER; and vascular, bronchial, gastrointestinal, and genitourinary SMOOTH MUSCLE.

Mechanisms of beta-lactam resistance amongst Pseudomonas aeruginosa isolated in an Italian survey. (1/1038)

The mechanisms of resistance to beta-lactam antibiotics in 325 isolates of Pseudomonas aeruginosa were examined. These isolates were selected because of their resistance to meropenem and imipenem (breakpoint, >4 mg/L), carbenicillin (>128 mg/L), ceftazidime (>8 mg/L), piperacillin and ticarcillin/clavulanate (>64 mg/L). The most frequent mechanism of resistance was beta-lactamase-independent, so called 'intrinsic resistance', which was found in 183 isolates and was probably due to impermeability and/or efflux mechanisms. beta-Lactamase-mediated resistance was demonstrated in 111 strains (11.1%). Derepression of Ambler Class C chromosomal beta-lactamase was detected in 64 isolates, most of which were resistant to ceftazidime and piperacillin but susceptible to meropenem, whereas secondary plasmid-encoded beta-lactamases were found in 34 isolates, all of them resistant to carboxypenicillins and ureidopenicillins and susceptible to carbapenems. Twelve strains showed more than one plasmid-encoded beta-lactamase plus derepression of chromosomal Class C enzyme. Resistance to carbapenems was independent of resistance to other beta-lactam antibiotics, indicating a different mechanism of resistance, probably due to the loss of the D2 porin. In total, 32 strains were resistant to carbapenems: 24 only to imipenem and eight to both imipenem and meropenem.  (+info)

Ampicillin-sulbactam and amoxicillin-clavulanate susceptibility testing of Escherichia coli isolates with different beta-lactam resistance phenotypes. (2/1038)

The activities of ampicillin-sulbactam and amoxicillin-clavulanate were studied with 100 selected clinical Escherichia coli isolates with different beta-lactam susceptibility phenotypes by standard agar dilution and disk diffusion techniques and with a commercial microdilution system (PASCO). A fixed ratio (2:1) and a fixed concentration (clavulanate, 2 and 4 micrograms/ml; sulbactam, 8 micrograms/ml) were used in the agar dilution technique. The resistance frequencies for amoxicillin-clavulanate with different techniques were as follows: fixed ratio agar dilution, 12%; fixed concentration 4-micrograms/ml agar dilution, 17%; fixed ratio microdilution, 9%; and disk diffusion, 9%. Marked discrepancies were found when these results were compared with those obtained with ampicillin-sulbactam (26 to 52% resistance), showing that susceptibility to amoxicillin-clavulanic acid cannot be predicted by testing the isolate against ampicillin-sulbactam. Interestingly, the discrimination between susceptible and intermediate isolates was better achieved with 4 micrograms of clavulanate per ml than with the fixed ratio. In contrast, amoxicillin susceptibility was not sufficiently restored when 2 micrograms of clavulanate per ml was used, particularly in moderate (mean beta-lactamase activity, 50.8 mU/mg of protein) and high-level (215 mU/mg) TEM-1 beta-lactamase producer isolates. Four micrograms of clavulanate per milliliter could be a reasonable alternative to the 2:1 fixed ratio, because most high-level beta-lactamase-hyperproducing isolates would be categorized as nonsusceptible, and low- and moderate-level beta-lactamase-producing isolates would be categorized as nonresistant. This approach cannot be applied to sulbactam, either with the fixed 2:1 ratio or with the 8-micrograms/ml fixed concentration, because many low-level beta-lactamase-producing isolates would be classified in the resistant category. These findings call for a review of breakpoints for beta-lactam-beta-lactamase inhibitors combinations.  (+info)

Identification and characterization of a new porin gene of Klebsiella pneumoniae: its role in beta-lactam antibiotic resistance. (3/1038)

Klebsiella pneumoniae porin genes were analyzed to detect mutations accounting for the porin deficiency observed in many beta-lactam-resistant strains. PCR and Southern blot analysis revealed the existence of a third porin gene in addition to the OmpK36 and OmpK35 porin genes previously described. This new porin gene was designated ompK37 and is present in all of the clinical isolates tested. The OmpK37 porin gene was cloned, sequenced, and overexpressed in Escherichia coli. In contrast to that of the major porins, OmpK37 porin expression was only detectable by Western blot analysis in porin-deficient beta-lactam-resistant strains, suggesting strong down regulation under standard laboratory conditions. Functional characterization suggested a narrower pore for the OmpK37 porin than for K. pneumoniae porins OmpK36 and OmpK35. This correlated with the susceptibility to certain beta-lactam antibiotics, since a K. pneumoniae strain expressing porin OmpK37, but not porin OmpK36 or OmpK35, was less susceptible to beta-lactam antibiotics than the same strain expressing either porin OmpK36 or OmpK35.  (+info)

Genetic characterization of resistance to extended-spectrum beta-lactams in Klebsiella oxytoca isolates recovered from patients with septicemia at hospitals in the Stockholm area. (4/1038)

Two beta-lactamase gene regions were characterized by DNA sequencing in eight clinical isolates of Klebsiella oxytoca. The blaOXY-2a region encoded a beta-lactamase nearly identical to OXY-2 (one amino acid residue substituted) and conferred aztreonam and cefuroxime resistance on the K. oxytoca isolates. Overproduction of OXY-2a was caused by a G-to-A substitution of the fifth nucleotide in the -10 consensus sequence of blaOXY-2a. The blaOXY-1a was identified in a susceptible strain, and the OXY-1a enzyme differed from OXY-1 by two amino acid residues.  (+info)

Resistance to beta-lactam antibiotics in Pseudomonas aeruginosa due to interplay between the MexAB-OprM efflux pump and beta-lactamase. (5/1038)

We evaluated the roles of the MexAB-OprM efflux pump and beta-lactamase in beta-lactam resistance in Pseudomonas aeruginosa by constructing OprM-deficient, OprM basal level, and OprM fully expressed mutants from beta-lactamase-negative, -inducible, and -overexpressed strains. We conclude that, with the notable exception of imipenem, the MexAB-OprM pump contributes significantly to beta-lactam resistance in both beta-lactamase-negative and beta-lactamase-inducible strains, while the contribution of the MexAB-OprM efflux system is negligible in strains with overexpressed beta-lactamase. Overexpression of the efflux pump alone contributes to the high level of beta-lactam resistance in the absence of beta-lactamase.  (+info)

Inhibitor-resistant TEM beta-lactamases: phenotypic, genetic and biochemical characteristics. (6/1038)

Beta-lactamases represent the main mechanism of bacterial resistance to beta-lactam antibiotics. The recent emergence of bacterial strains producing inhibitor-resistant TEM (IRT) enzymes could be related to the frequent use of beta-lactamase inhibitors such as clavulanic acid, sulbactam and tazobactam in hospitals and in general practice. The IRT beta-lactamases differ from the parental enzymes TEM-1 or TEM-2 by one, two or three amino acid substitutions at different locations. This paper reviews the phenotypic, genetic and biochemical characteristics of IRT beta-lactamases in an attempt to shed light on the pressures that have contributed to their emergence.  (+info)

Proficiency of clinical laboratories in Spain in detecting vancomycin-resistant Enterococcus spp. The Spanish VRE Study Group. (7/1038)

Studies in a variety of U.S. clinical laboratories have demonstrated difficulty in detecting intermediate and low-level vancomycin-resistant enterococci (VRE). The misclassification of "at least intermediate resistant isolates" as vancomycin susceptible may have both clinical implications and a negative impact on measures to control the spread of VRE. No published study has assessed the ability of clinical laboratories in Europe to detect VRE. So, the apparent low prevalence of VRE in European hospitals may be, in part, secondary to the inability of these laboratories to detect all VRE. In an effort to assess European laboratories' proficiency in detecting VRE, we identified 22 laboratories in Spain and asked them to test four VRE strains and one susceptible enterococcal strain from the Centers for Disease Control and Prevention collection. Each organism was tested by the routine antimicrobial susceptibility testing method used by each laboratory. Overall, VRE were correctly identified in 61 of 88 (69.1%) instances. The accuracy of VRE detection varied with the level of resistance and the antimicrobial susceptibility method. The high-level-resistant strain (Enterococcus faecium; MIC, 512 microg/ml) was accurately detected in 20 of 22 (91. 3%) instances, whereas the intermediate-resistant isolate (Enterococcus gallinarum; MIC, 8 microg/ml) was accurately detected in only 11 of 22 (50%) instances. Classification errors occurred in 27 of 88 (30.9%) instances. Misclassification as vancomycin susceptible was the most common error (16 of 27 [59.3%] instances). Our study shows that the participating Spanish laboratories had an overall acceptable proficiency in detecting VRE but that a substantial proportion of VRE isolates with low or intermediate levels of resistance were not detected. We recommend that studies be conducted to validate laboratory proficiency testing as an important step in the prevention and control of the spread of antimicrobial resistance.  (+info)

Aspartic acid for asparagine substitution at position 276 reduces susceptibility to mechanism-based inhibitors in SHV-1 and SHV-5 beta-lactamases. (8/1038)

In SHV-type beta-actamases, position 276 (in Ambler's numbering scheme) is occupied by an asparagine (Asn) residue. The effect on SHV-1 beta-lactamase and its extended-spectrum derivative SHV-5 of substituting an aspartic acid (Asp) residue for Asn276 was studied. Mutations were introduced by a PCR-based site-directed mutagenesis procedure. Wild-type SHV-1 and -5 beta-lactamases and their respective Asn276-->Asp mutants were expressed under isogenic conditions by cloning the respective bla genes into the pBCSK(+) plasmid and transforming Escherichia coli DH5alpha. Determination of IC50 showed that SHV-1(Asn276-->Asp), compared with SHV-1, was inhibited by 8- and 8.8-fold higher concentrations of clavulanate and tazobactam respectively. Replacement of Asn276 by Asp in SHV-5 beta-lactamase caused a ten-fold increase in the IC50 of clavulanate; the increases in the IC50s of tazobactam and sulbactam were 10- and 5.5-fold, respectively. Beta-lactam susceptibility testing showed that both Asn276-->Asp mutant enzymes, compared with the parental beta-lactamases, conferred slightly lower levels of resistance to penicillins (amoxycillin, ticarcillin and piperacillin), cephalosporins (cephalothin and cefprozil) and some of the expanded-spectrum oxyimino beta-lactams tested (cefotaxime, ceftriaxone and aztreonam). The MICs of ceftazidime remained unaltered, while those of cefepime and cefpirome were slightly elevated in the clones producing the mutant beta-lactamases. The latter clones were also less susceptible to penicillin-inhibitor combinations. Asn276-->Asp mutation was associated with changes in the substrate profiles of SHV-1 and SHV-5 enzymes. Based on the structure of TEM-1 beta-lactamase, the potential effects of the introduced mutation on SHV-1 and SHV-5 are discussed.  (+info)

Nonsusceptibility of bacteria to the action of the beta-lactam antibiotics. Mechanisms responsible for beta-lactam resistance may be degradation of antibiotics by BETA-LACTAMASES, failure of antibiotics to penetrate, or low-affinity binding of antibiotics to targets.
Antibiotics and antibiotic resistant bacteria enter wastewater treatment plants (WWTPs), an environment where resistance genes can potentially spread and exchange between microbes. Several antibiotic resistance genes (ARGs) were quantified using qPCR in three WWTPs of decreasing capacity located in Helsinki, Tallinn, and Tartu, respectively: sulphonamide resistance genes (sul1 and sul2), tetracycline resistance genes (tetM and tetC), and resistance genes for extended spectrum beta-lactams (blaoxa-58, blashv-34, and blactx-m-32). To avoid inconsistencies among qPCR assays we normalised the ARG abundances with 16S rRNA gene abundances while assessing if the respective genes increased or decreased during treatment. ARGs were detected in most samples; sul1, sul2, and tetM were detected in all samples. Statistically significant differences (adjusted p,0.01) between the inflow and effluent were detected in only four cases. Effluent values for blaoxa-58 and tetC decreased in the two larger plants while ...
The NDM-1 gene, first identified in Sweden in 2008 in Klebsiella pneumoniae from a patient hospitalized in New Delhi, encodes a metallo-β-lactamase that inactivates all β-lactams except aztreonam. This bla(NDM-1) gene has been identified in hospital-acquired bacterial species, such as K. pneumoniae, …
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have discovered a novel mechanism of resistance to ?-lactams that is independent of penicillinase and the low affinity penicillin bindin protein (PBP), PBP2a, the two known mechanisms of ?-lactam resistance in Staphylococcus aureus. This new type of resistance was identified during experiments in which methicillin- susceptible S. aureus strains were passaged in the presence of each of the two so-called fifth generation anti-MRSA cephalosporins, ceftobiprole and ceftaroline. Whole genome sequencing of a ceftobiprole- passage mutant revealed mutations in genes encoding PBP4, a non-essential, low-molecular weight PBP; GdpP, a putative signaling protein; and AcrB, a putative transporter. Ceftaroline also selected for PBP4 and GdpP mutants, but not AcrB mutants, indicating the primary importance of the former two proteins. We hypothesize 1) that a gain of transpeptidase function by mutant PBP4 accounts for high-level ?-lactam resistance; and 2) that GdpP contributes to resistance via a signaling ...
Aim and Background:Eradicating infections is difficult due to the presence of genes on the introns, especially the beta-lactamase enzymes and  The importance of their resistance is high.The purpose of this study was to determine the beta-lactamase genes (OXA-2 , OXA-10) , Integron class 1  and antibiotic resistance. Material and methods:In this cross ...
The optimal method to screen for gastrointestinal colonization with carbapenem-resistant organisms (CRO) has yet to be established. The direct MacConkey (direct MAC) plate method demonstrates high sensitivity for CRO detection, but established zone diameter (ZD) criteria for ertapenem (≤27 mm) and meropenem (≤32 mm) result in high rates of false positives upon confirmatory testing. To increase specificity, we screened for CRO in two high-risk wards using the direct MAC plate method, recorded ZDs for each sample, and generated receiver operating characteristic (ROC) curves to evaluate the optimal ZD cutoff criteria. Of 6,868 swabs obtained over an 18-month period, 4,766 (69%) had growth on MAC plates, and 2,500 (36%) met criteria for further evaluation based on previously established ZDs around the carbapenem disks. A total of 812 (12%) swabs were confirmed positive for at least one CRO and included 213 (3%) carbapenemase-producing organisms (CPO), resulting in a specificity of 78% for the ...
Publisher : International Dairy Federation All titles : An evaluation of the Idexx SNAP test for detecting beta-Lactam antibiotics in raw milk [enzyme linked receptor-binding assay] ...
1IYS: Crystal Structure of Extended-Spectrum beta-Lactamase Toho-1: Insights into the Molecular Mechanism for Catalytic Reaction and Substrate Specificity Expansion
1IYS: Crystal Structure of Extended-Spectrum beta-Lactamase Toho-1: Insights into the Molecular Mechanism for Catalytic Reaction and Substrate Specificity Expansion
TY - JOUR. T1 - Environmental exposure to carbapenem-resistant Acinetobacter baumannii as a risk factor for patient Acquisition of A. baumannii. AU - Rosa, Rossana. AU - Arheart, Kristopher L.. AU - Depascale, Dennise. AU - Cleary, Timothy. AU - Kett, Daniel H.. AU - Namias, Nicholas. AU - Pizano, Louis. AU - Fajardo-Aquino, Yovanit. AU - Silvia Munoz-Price, L.. PY - 2014. Y1 - 2014. N2 - We aimed to determine the association between environmental exposure to carbapenem-resistant Acinetobacter baumannii and the subsequent risk of acquiring this organism. Patients exposed to a contaminated hospital environment had 2.77 times the risk of acquiring carbapenem-resistant A. baumannii than did unexposed patients (relative risk, 2.77 [95% confidence interval, 1.50-5.13]; P p.002).. AB - We aimed to determine the association between environmental exposure to carbapenem-resistant Acinetobacter baumannii and the subsequent risk of acquiring this organism. Patients exposed to a contaminated hospital ...
Background: Carbapenem antibiotics are important therapeutic agents in the health care setting, they are frequently used as an empiric therapy for life-threatening infections as well as infections with multi-drug-resistant gram-negative bacilli. Carbapenemase-producing Carbapenem-Resistant Enterobacteriaceae (CRE) are a significant public health challenge worldwide. The detection of carbapenemases productions in CRE strains is performed by phenotypic and genotypic methods. The phenotypic methods target carbapenemases production but provide no guidance regarding the specific carbapenemases types, while the genotypic diagnosis has the benefit of determining the exact mechanism conferring carbapenems resistance. Aim: Improvement of the antibiotic policy and infection control strategies in Suez Canal University Hospitals in Ismailia; through adequate detection of carbapenem resistance in the hospitals. Methods: All the CRE isolates were tested by the phenotypic methods (mCIM & eCIM) test to detect
Infections with carbapenemase-producing carbapenem-resistant Enterobacteriaceae (CP-CRE) are associated with high mortality rates (1). Carbapenemases encoded on plasmids can move between bacterial strains and have the potential to rapidly increase the proportion of Enterobacteriaceae resistant to carbapenems; as such, CP-CRE have been a particular focus of public health response. Although the Enterobacteriaceae family includes approximately 50 recognized genera, surveillance for CP-CRE has focused on the organisms most associated with clinical infections: Klebsiella spp., Enterobacter spp., and Escherichia coli (2,3). CRE from other, less commonly encountered genera (hereafter referred to as less common genera) have generally not been targeted for carbapenemase testing, in part, because some of these organisms possess intrinsic resistance to the carbapenem imipenem and others express species-specific chromosomal carbapenemases. However, these organisms can also harbor plasmid-mediated ...
Carbapenem-resistant Acinetobacter baumannii is the top-ranked pathogen in the World Health Organization priority list of antibiotic-resistant bacteria. It emerged as a global pathogen due to the successful expansion of a few epidemic lineages, or international clones (ICs), producing acquired class D carbapenemases (OXA-type). During the past decade, however, reports regarding IC-I isolates in Latin America are scarce and are non-existent for IC-II and IC-III isolates. This study evaluates the molecular mechanisms of carbapenem resistance and the epidemiology of 80 non-duplicate clinical samples of A. baumannii collected from February 2014 through April 2016 at two tertiary care hospitals in Lima. Almost all isolates were carbapenem-resistant (97.5%), and susceptibility only remained high for colistin (95%). Pulsed-field gel electrophoresis showed two main clusters spread between both hospitals: cluster D containing 51 isolates (63.8%) associated with sequence type 2 (ST2) and carrying OXA-72, ...
Trends in carbapenem-resistant Enterobacteriaceae (CRE) collected from hospitals nationwide in Singapore over 3 years are presented. Hospital isolates with imipenem or meropenem minimum inhibitory concentrations (MICs) of ,1 mg/L were sent to the National Public Health Laboratory for further investigation. A total of 400 CRE were submitted, 227 (56.8%) of which carried a carbapenemase gene. blaNDM was the most common (130/400; 32.5%), followed by blaOXA-48-like (blaOXA-48, -181, -232) (55/400; 13.8%). Interestingly, four isolates bearing dual carbapenemase genes were also detected. KPC- and OXA-48-like-producing Klebsiella pneumoniae were fingerprinted by DiversiLab® rep-PCR. Locally, KPC producers do not appear to have clonal dissemination. In contrast, OXA-48-like producers were found to have a greater degree of clustering than KPC producers. © 2013 International Society for Chemotherapy of Infection and Cancer ...
Acinetobacter baumannii is a nosocomial pathogen which is establishing as a major cause of morbidity and mortality within the healthcare community. The success of this pathogen is largely due to its ability to rapidly gain resistance to antimicrobial therapies and its capability to persist in an abiotic environment through the production of a biofilm. Our tertiary-care hospital has showed high incidence of carbapenem-resistant Acinetobacter baumannii (CRAB) isolates. In this study we explore both genotypic and phenotypic properties of 26 CRAB isolates: 16 isolates were collected from January 2010 to March 2011, and 10 were collected between February and May 2015. We determined that all 26 CRAB isolates possessed multiple β-lactamase genes, including genes from Groups A, C, and D. Specifically, 42% of the isolates possesses the potentially plasmid-borne genes of OXA-23-like or OXA-40-like β-lactamase. The presence of mobile gene element integron cassettes and/or integrases
Carbapenem-resistant Enterobacteriaceae (CRE) has been declared among the most immediate drug-resistant threats to america. when utilized as monotherapy in the treating CRE attacks.3,6C8 A far more recent antibiotic, ceftazidimeCavibactam (FDA-approved in 2015), shows improved safety and efficiency outcomes in comparison to traditional agents, but reports of treatment resistance and failure during therapy have already been noted.9C11 MeropenemCvaborbactam was approved by the FDA in August 2017 as the initial carbapenem beta-lactamase inhibitor mixture with activity against broad-spectrum beta-lactamases in CRE infections. Signs12 MeropenemCvaborbactam is certainly indicated for the treating complicated urinary system attacks (cUTI), including pyelonephritis, in adults aged 18 years and old. MECHANISM OF Actions8,12 Meropenem, a carbapenem antibacterial agent, disrupts bacterial cell-wall synthesis by inhibiting penicillin-binding proteins leading to cell loss of life. Vaborbactam is certainly a ...
N.C. Communicable Disease Branch page about new carbapenem-resistant Enterobacteriaceae (CRE), untreatable or difficult-to-treat Enterobacteriaceae that have developed high levels of resistance to antibiotics, including last-resort antibiotics called carbapenems. Includes NC DHHS and CDC communications about this emerging public health concern as well as links to infection prevention information tailored for patients and healthcare providers.
Carbapenem-Resistant Enterobacteriaceae (CRE) are untreatable or difficult to treat bacteria that are resistant to carbapenem antibiotics and nearly all available antibiotics. They can cause serious illness and death; bloodstream infections are fatal in 40% -50% of cases. CRE was designated by the CDC in 2013 as one of the three most urgent drug resistant threats in the United States. An estimated 9,000 CRE infections cause 600 deaths yearly in the U.S.. Risk factors for CRE colonization or infection include open wounds, presence of indwelling devices (such as endotracheal tubes, feeding tubes, and catheters), multiple medical problems, and high antimicrobial use. CRE are easily spread between infected or colonized patients by health care workers and equipment, unless rigorous infection prevention precautions are taken. Cases and outbreaks of CRE have been increasingly recognized in recent years in Northern California, including Alameda County. In June 2017, the Alameda County Public Health ...
Provider Role in Transmission of Carbapenem-Resistant Enterobacteriaceae - Volume 38 Issue 11 - Marika E. Grabowski, Hyojung Kang, Kristen M. Wells, Costi D. Sifri, Amy J. Mathers, Jennifer M. Lobo
Carbapenem-resistant Enterobacteriaceae (CRE) are a serious threat to public health. Infections with CRE are difficult, and in some cases impossible, to treat and have been associated with mortality rates up to 50%(1). Due to the movement of patients throughout the healthcare system, if CRE are a problem in one facility, then typically they are a problem in other facilities in the region as well. To help protect patients and prevent transmission, CDC has updated 2012 CRE toolkit; this document will continue to be updated as new information becomes available.. ...
Would infants be at high risk for carbapenem-resistant Enterobacteriaceae or CRE infection? Find answers now! No. 1 Questions & Answers Place.
PubMedID: 24985124 | Successful management of an outbreak due to carbapenem-resistant Acinetobacter baumannii in a neonatal intensive care unit. | European journal of pediatrics | 7/2/2014
The nexus between resistance determinants, plasmid type, and clonality appears to play a crucial role in the dissemination and survival of carbapenem-resistant Klebsiella pneumoniae (CRKP). The incidence of infections involving CRKP in Saudi Arabia is increasing and there is a need for detailed molecular profiling of this pathogen for CRKP surveillance and control. The resistance determinants of 71 non-redundant CRKP isolates were investigated by polymerase chain reaction (PCR) and sequencing. Plasmid typing was performed using PCR-based replicon typing and the clonality of isolates was determined by multilocus sequence typing. Capsular polysaccharide synthesis genes and other virulence factors were examined using multiplex PCR. Diversity was calculated using DIVEIN, clonal relationship was determined using eBURST, and phylogenetic analysis was performed using SplitsTree4. A polyclonal OXA-48 gene alone was the most common carbapenemase detected in 48/71 (67.6%) isolates followed by NDM-1 alone in 9/71
Schwaber et al identified risk factors for acquisition of carbapenem-resistant Klebsiella pneumoniae in a hospitalized patient. These can help to identify a patient who should be screened for carriage. The authors are from Tel Aviv Sourasky Medical Center.
Despite the unfavorable double-room configuration of our ICU, the 4.1% rate of ESBL acquisition was much lower than the 13% reported by Razazi et al. in a 24-bed ICU with eight single rooms but without any protocol of contact precautions for ESBL carriers [13]. It is close to that reported by Alves et al. in an ICU with only single rooms, in which contact precautions were also applied [17]. Unlike Barbier et al., who reported that half of the ESBL carriers acquired their ESBL during their ICU stay [16], and Gardam et al., who reported that ESBL acquisition accounted for two-thirds of ESBL carriage in the ICU [18], ESBL acquisition accounted for only 12.7% of all ESBL carriage in our study, confirming that ESBL carriage is mostly imported, whereas high-level cephalosporinase (HL-Case) is mostly acquired, in the ICU [19]. In multivariate analysis, the severity (SAPS II) at admission was the only factor identified to be associated with the acquired carriage of ESBL, while some authors have reported ...
Many gaps in the burden of resistant pathogens exist in endemic areas of low- and middle-income economies, especially those endemic for carbapenem resistance. The aim of this study is to evaluate risk factors for carbapenem-resistance, to estimate the association between carbapenem-resistance and all-cause 30-day mortality and to examine whether mortality is mediated by inappropriate therapy. A case-control and a cohort study were conducted in one tertiary-care hospital in Medellín, Colombia from 2014 to 2015. Phenotypic and genotypic characterization of isolates was performed. In the case-control study, cases were defined as patients infected with carbapenem-resistant K. pneumoniae (CRKP) and controls as patients infected with carbapenem-susceptible K. pneumoniae (CSKP). A risk factor analysis was conducted using logistic regression models. In the cohort study, the exposed group was defined as patients infected with CRKP and the non-exposed group as patients infected with CSKP. A survival analysis
Infections caused by carbapenem-resistant Enterobacteriaceae are a growing concern worldwide. Raoultella ornithinolytica is a species in the Enterobacteriaceae family which can cause hospital-acquired infections and is sporadically reported as carbapenem-resistant from human and environmental sources. In this study, we firstly report on an NDM-1-producing R. ornithinolytica, Rao166, isolated from drinking water in an animal cultivation area in China. In addition to carbapenem-resistance, Rao166 was resistant to several other antibiotics including gentamicin, sulfamethoxazole-trimethoprim, tetracycline and fosfomycin. Rao166 carried a novel IncFIC-type megaplasmid, 382,325 bp in length (pRAO166a). A multidrug resistance region, 60,600 bp in length, was identified in the plasmid containing an aac(3)-IId-like gene, aac(6)-Ib-cr, blaDHA-1, blaTEM-1B, blaCTX-M-3, blaOXA-1, blaNDM-1, qnrB4, catB3, arr-3, sul1, and tet(D). Results from virulence assays implied that Rao166 has considerable pathogenic ...
What are carbapenem-resistant Enterobacteriaceae (CRE)? Enterobacteriaceae are a group of bacteria normally found in the human gut. Common types include E. coli and Klebsiella species. Carbapenems are a class of antibiotics that were developed to treat bacteria that are resistant to other drugs. Due to the overuse of these antibiotics, some types of Enterobacteriaceae have developed resistance to carbapenems; these bacteria are called carbapenem-resistant Enterobacteriaceae (CRE).. Who gets CRE? Healthy people usually do not get CRE infections. In healthcare settings, CRE infections may occur among patients who are receiving treatment for other conditions. Patients whose care requires devices like ventilators (breathing machines), urinary (bladder) catheters, or intravenous (vein) catheters, and patients who are taking long courses of certain antibiotics are most at risk for CRE infections.. How are CRE spread? CRE can be transmitted via direct person-to-person contact with an infected person or ...
Salloum N A, Kissoyan K A, Fadlallah S, Cheaito K, Araj G F, Wakim R, Kanj S, Kanafani Z, Dbaibo G, Matar G M (2015); Front Microbiol., 6:999. doi: 10.3389/fmicb.2015.00999. ...
It was a week into my elderly patients hospital admission when he began to have fever and profuse diarrhea, some 10-12 bowel movement a day. The diagnosis was not hard to make: a stool test showed he had C difficile. Another patient, a thin women in her late 40s who had become paraplegic after a […]. ...
(PRWEB) May 15, 2015 -- GeneWEAVE, Inc.,a clinical diagnostics company addressing multi-drug-resistant organisms (MDRO), announced that initial data presented
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Learn how HABP/VABP is increasingly caused by carbapenem-resistant Gram-negative pathogens. Please see Important Safety Information and Full Prescribing Information on this website.
On the right plate, carbapenem-resistant Enterobacteriaceae is able to grow even in the presence of antibiotics. Photo by CDC A ...
Besides the constant care of patients, healthcare facilities have one more thing on their hands: the CRE (carbapenem-resistant Enterobacteriaceae) bacteria. This lethal enemy is unfortunately growing to be very common in intensive care settings to the point that there is an alert rising due to this.
Brink, Adrian et al. The spread of carbapenem-resistant Enterobacteriaceae in South Africa: Risk factors for acquisition and prevention. SAMJ, S. Afr. med. j., July 2012, vol.102, no.7, p.599-601. ISSN 0256- ...
After reports that a dangerous drug-resistant bacterium, carbapenem-resistant Klebsiella pneumoniae, or CRKP, had spread to at least 356 patients in Southern California last year, Times staff writer
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
PubMed comprises more than 30 million citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.
James Foster (foster at cs.uidaho.edu) wrote: ,Ahhh...gotcha. That is indeed an interesting question. Im not sure ,what the answer is. I know that many new functions are co-opted from ,similar functions (I think the classical example is some enzyme ,beginning with the letter l...but cant remember right now). But that ,begs the question of where the co-opted behaviors came from. True, and I think also the important issue is how this new function arose from a similar function. The evolution, and natural selection, of classes of beta-lactamases are the examples I know. While we havent observed it, the early beta-lactamases are hypothesised to have arisen from cell-wall enzymes and the bacteria were facing an enemy in nature (beta-lactams in fungi). Today, we have artificial beta-lactams that are not seen anywhere in nature, yet there are bacteria resistant to it. One explanation that this new function /arose/ (evolved) in the the last few decades, compared to the initial ones, which mightve ...
Mono- and Stereopictres of 5.0 Angstrom coordination sphere of Potassium atom in PDB 2ffy: Ampc Beta-Lactamase N289A Mutant in Complex With A Boronic Acid Deacylation Transition State Analog Compound SM3
The global dissemination of carbapenem-resistant Gram-negative pathogens is a significant source of morbidity and mortality. Carbapenemases, or carbapenem-hydro...
The global dissemination of carbapenem-resistant Gram-negative pathogens is a significant source of morbidity and mortality. Carbapenemases, or carbapenem-hydro...
Escherichia coli and other species of Enterobacteriaceae producing CTX-M type extended-spectrum beta-lactamases (ESBLs) have been reported from a number of European countries
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Backbone RMSDs are shown for native and S130 mutant SHV β-lactamase at 300 K, black color indicate native SHV, point mutant form S130G SHV β-lactamase shown i
Veinberg G.; Shestakova I.; Bokaldere R.; Dikovskaya K.; Grigan N.; Musel D.; Vorona M.; Kanepe I.; Domracheva I.; Zharkova O.; Mežapuķe R.; Kalvinsh I.; Lukevics E. Cytotoxic properties of beta-lactam antibiotics structural analogs. Abstr., Baltijas valstu onkologu un radiologu 2. kongr. = 2nd Baltic congr. of oncology and radiology; 10.-12. sept.: Rīga, Latvija, 1998; 173 ...
A growing body of evidence and expert reviews suggests that we should be altering our administration regimes of beta-lactam and carbapenams to accommodate an altered volume of distribution (or RRT) status of the critically ill patient in order to more effectively reach the inhibitory concentrations of drug required to kill susceptible pathogens. ...
Zapun, André; Contreras-Martel, Carlos; Vernet, Thierry (2008). "Penicillin-binding proteins and beta-lactam resistance". FEMS ... Rice, Louis B. (2012). "Mechanisms of resistance and clinical relevance of resistance to β-lactams, glycopeptides, and ... The β-lactam ring is itself fused to a five-membered thiazolidine ring. The fusion of these two rings causes the β-lactam ring ... 6-Aminopenicillanic acid (6-APA) is a compound derived from penicillin G. 6-APA contains the beta-lactam core of penicillin G, ...
Kong, Kok-Fai; Schneper, Lisa; Mathee, Kalai (2010). "Beta-lactam antibiotics: from antibiosis to resistance and bacteriology ... James CW, Gurk-Turner C (January 2001). "Cross-reactivity of beta-lactam antibiotics". Proceedings. 14 (1): 106-7. doi:10.1080/ ... 6-APA was found to constitute the core 'nucleus' of penicillin (in fact, all β-lactam antibiotics) and was easily chemically ... "Penicillin X-ray data showed that proposed β-lactam structure was right". C&EN. Retrieved 21 August 2018. Hodgkin DC (July 1949 ...
KF, Kong (January 2010). "Beta-lactam antibiotics: from antibiosis to resistance and bacteriology". APMIS. 118 (1): 1-36. doi: ... have become better understood through the study of how antibiotics affect beta-lactam development through the antibiosis ... "Antibiosis resistance affects the biology of the insect so pest abundance and subsequent damage is reduced compared to that ... Antibiosis resistance often results in increased mortality or reduced longevity and reproduction of the insect." Antibiotic ...
Poole K (September 2004). "Resistance to beta-lactam antibiotics". Cellular and Molecular Life Sciences. 61 (17): 2200-23. doi: ... Wilke MS, Lovering AL, Strynadka NC (October 2005). "Beta-lactam antibiotic resistance: a current structural perspective". ... Gin A, Dilay L, Karlowsky JA, Walkty A, Rubinstein E, Zhanel GG (June 2007). "Piperacillin-tazobactam: a beta-lactam/beta- ... as the beta-lactam ring is hydrolyzed by the bacteria's beta-lactamase. It was patented in 1974 and approved for medical use in ...
Fisher JF, Meroueh SO, Mobashery S (Feb 2005). "Bacterial resistance to beta-lactam antibiotics: compelling opportunism, ... which hydrolyzes the beta-lactam ring, rendering the drug inactive. This contributes to antibacterial resistance towards ... Cefalexin is a beta-lactam antibiotic of the cephalosporin family. It is bactericidal and acts by inhibiting synthesis of the ... Cefalexin is a beta-lactam antibiotic within the class of first-generation cephalosporins. It works similarly to other agents ...
Fisher JF, Meroueh SO, Mobashery S (February 2005). "Bacterial resistance to beta-lactam antibiotics: compelling opportunism, ... to antibiotics such as penicillin because enzymes called beta-lactamases are induced that hydrolyse the crucial beta-lactam ... Okada S, O'Brien JS (August 1969). "Tay-Sachs disease: generalized absence of a beta-D-N-acetylhexosaminidase component". ... Bennett PM, Chopra I (1993). "Molecular basis of beta-lactamase induction in bacteria". Antimicrob. Agents Chemother. 37 (2): ...
Bush, K; Tanaka, S K; Bonner, D P; Sykes, R B (1985-04-01). "Resistance caused by decreased penetration of beta-lactam ... Resistance caused by decreased penetration of beta-lactam antibiotics into Enterobacter cloacae. Antimicrob. Agents Chemother. ... Bush conducts research focusing on bacterial resistance mechanisms to beta-lactam antibiotics. Bush received her BA, magna cum ... Bush has continued to lead research characterizing beta-lactam resistance in enteric bacteria and collaborates with ...
... is in the penicillin group of beta-lactam antibiotics and is part of the aminopenicillin family. It is roughly ... Delcour AH (May 2009). "Outer membrane permeability and antibiotic resistance". Biochimica et Biophysica Acta (BBA) - Proteins ... Petri (2011). "Penicillins, Cephalosporins, and Other Beta-Lactam Antibiotics". In Brunton L, Chabner B, Knollman B (eds.). ... as they have low bioavailability of beta-lactams. The half-life in animals is around that same of that in humans (just over an ...
Drug resistance plasmide, Baltimore, University Park Press 1977. *Ed. Beta-lactam antibiotics, Japan Scientific Societies Press ... Transferable drug resistance factor R, Tokyo University Press 1971. *Ed. com Hajime Hashimoto: Microbiological drug resistance ... com Ladislav Rosival, V. Krčméry Antibiotic resistance: transposition and other elements, Avicenium 1980 ...
Metallo-beta-lactamases: a last frontier for beta-lactams? Lancet Infectious Diseases. 11 (5), 381-393 (2011). Deshpande LM, ... Microbial Drug Resistance. 14 (1), 45-47 (2008). Falcone M, Mezzatesta ML, Perilli MG et al. Infections with VIM-1 metallo-beta ... Emergence of antibiotic resistance during therapy for infections caused by Enterobacteriaceae producing AmpC beta-lactamase ... Microbial Drug Resistance. 8, 281-289 (2002). Ruiz J. Mechanisms of resistance to quinolones: target alterations, decreased ...
Various strains tested have shown resistance to beta lactam antibiotics, lincosamides, macrolides, and quinolones. Multiple ... One of C. amycolatum's characteristic traits is its resistance to a wide range of antibiotics. ...
... they give some strains antibiotic resistance by degrading beta-lactam antibiotics (such as penicillins). However, the protein ... Lactamase, beta 2 is a protein that in humans is encoded by the LACTB2 gene. LACTB2 is located on the 8th chromosome, with its ... "Entrez Gene: Lactamase, beta 2". Retrieved 2015-07-07. CS1 maint: discouraged parameter (link) Dominski Z (2007-03-01). " ... The metallo beta-lactamases were first identified in bacteria; ... "Nucleases of the metallo-beta-lactamase family and their role ...
... as beta-lactamase production is an important contributor to beta-lactam resistance in these pathogens. In contrast, most beta- ... non beta-lactam beta-lactamase inhibitor), and instead binds reversibly. Ambler Class B beta-lactamases cleave beta-lactams by ... Beta-lactamases are a family of enzymes involved in bacterial resistance to beta-lactam antibiotics. They act by breaking the ... This allows the degraded beta-lactam to diffuse away and frees up the enzyme to process additional beta-lactam molecules. ...
Since the discovery of the beta-lactam antibiotic penicillin, the rates of antimicrobial resistance have increased. Over time, ... Specific patterns of drug resistance or multi drug resistance may be noted, such as the presence of an extended-spectrum beta ... This resistance might be because a type of bacteria has intrinsic resistance to some antibiotics, because of resistance ... An example is the use of PCR to detect the mecA gene for beta-lactam resistant Staphylococcus aureus. Other examples include ...
However, resistance to penicillin and other beta-lactams may be transmitted from commensal neisseriae such as Neisseria ... "Neisseria lactamica and Neisseria polysaccharea as possible sources of meningococcal beta-lactam resistance by genetic ...
Gram-negative bacteria can develop and transfer β-lactam resistance (including carbapenem resistance) in many ways. They can ... Independent risk factors for CRE infection include use of beta-lactam antibiotics and the use of mechanical ventilation. ... Martin, SI; Kaye, KM (2004). "Beta-lactam antibiotics: newer formulations and newer agents". Infectious Disease Clinics of ... These enzymes cleave the β-lactam ring, an essential component of β-lactam antibiotics that are recognized by and bound to PBPs ...
This gave an increased resistance to β-lactamases due to stereochemical blocking of the beta-lactam ring. Cefuroxime was the ... The bacteria can also replace the PBP that is vulnerable to Beta-lactam antibiotics with PBP that is less vulnerable. β-lactam ... The enzymes hydrolyze the bond between the carbon and nitrogen atom of the β-lactam ring. There are many beta lactamases which ... Target alterations in the binding site of PBP have led to high-level resistance of β-lactams among bacterias like staphylococci ...
... (PTZ-601) is a broad spectrum injectable antibiotic, from the carbapenem subgroup of beta-lactam antibiotics. It was ... against Enterobacteriaceae with defined resistance mechanisms". The Journal of Antimicrobial Chemotherapy. 64 (2): 330-5. doi: ... developed as a replacement drug to combat bacteria that had acquired antibiotic resistance to commonly used antibiotics. ...
... but the emergence of beta-lactam-resistant strains has been observed as early as 1980. Genes for antibiotic resistance have ... This resistance is often linked to the production of beta- lactamases. Most beta-lactamases identified in Bacteroides, ... The high frequency of strains producing beta-lactamase limit the use of single beta-lactam antibiotics as first-line treatment ... Susceptibility to various beta-lactam antibiotics has been described as variable depending on the strain of Capnocytophaga. ...
Resistance of Streptococcus pneumoniae to penicillin and other beta-lactams is increasing worldwide. The major mechanism of ... or antimicrobial resistance). NDM-1 is an enzyme that makes bacteria resistant to a broad range of beta-lactam antibiotics. NDM ... Selective pressure is thought to play an important role, and use of beta-lactam antibiotics has been implicated as a risk ... Resistance to polymyxins first appear in 2011. An easier way for this resistance to spread, a plasmid known as MCR-1 was ...
Beta lactam resistance in these pathogens is most commonly due to the expression of beta lactamase enzymes. Between 2007 and ... Furthermore, carbapenems are typically unaffected by emerging antibiotic resistance, even to other beta-lactams. Carbapenem ... Pseudomonas produces an inducible broad spectrum beta lactamase, AmpC, that is produced in response to beta lactam exposure. ... Like other beta lactam antibiotics, they lack activity against atypical bacteria, which do not have a cell wall and are thus ...
For example, epicatechin gallate, a compound found in green tea, has shown signs of lowering the resistance to beta-lactams, to ... Severin A, Wu SW, Tabei K, Tomasz A (October 2005). "High-level (beta)-lactam resistance and cell wall synthesis catalyzed by ... Interactions with other genes decrease resistance to beta-lactams in resistant strains of S. aureus. These gene networks are ... 2a-mediated beta-lactam resistance by delocalizing PBP2". The Journal of Biological Chemistry. 285 (31): 24055-65. doi:10.1074/ ...
Beta-lactam antibiotics mimic the D-Ala-D-Ala site, thereby irreversibly inhibiting PBP crosslinking of peptidoglycan. ... Resistance to cephalosporin antibiotics can involve either reduced affinity of existing PBP components or the acquisition of a ... Overall, the research shows that all beta lactams have the intrinsic hazard of very serious hazardous reactions in susceptible ... "5.1.2 Cephalosporins and other beta-lactams". British National Formulary (56 ed.). London: BMJ Publishing Group Ltd and Royal ...
This multi-drug resistance has been linked to certain genes. For beta-lactam resistance, the mechanism is by altering ... Park J, Friendship RM, Weese JS, Poljak Z, Dewey CE (October 2013). "An investigation of resistance to β-lactam antimicrobials ... Further resistance testing of S. hyicus isolates found high resistance to penicillin, macrolides, tetracycline, sulfonamides ... Other implicated plasmid resistance genes are tet(L) for tetracyclines, erm(C) for macrolides, lincosamides and streptogramins ...
However, administered in combination with a beta-lactam antibiotic, aminoglycosides appear to produce a synergistic effect ... "Antibiotic susceptibility pattern and erythromycin resistance mechanisms in beta-hemolytic group G Streptococcus dysgalactiae ... Oppegaard, O; Mylvaganam, H; Kittang, BR (February 2015). "Beta-haemolytic group A, C and G streptococcal infections in Western ... Sylvetsky, N; Raveh, D; Schlesinger, Y; Rudensky, B; Yinnon, AM (1 June 2002). "Bacteremia due to beta-hemolytic Streptococcus ...
Like other penicillins and beta-lactam antibiotics, they contain a beta-lactam ring that is crucial to its antibacterial ... This does not, however, prevent resistance conferred by bacterial beta-lactamases. Members of this family include ampicillin, ...
It inhibits bacterial cell wall synthesis like other β-lactam antibiotics. In contrast to other beta-lactams, it is highly ... In general, resistance arises due to mutations in penicillin-binding proteins, production of metallo-β-lactamases, or ... In 2016, a synthetic peptide-conjugated PMO (PPMO) was found to inhibit the expression of New Delhi metallo-beta-lactamase, an ... As with other ß-lactams antibiotics, the effectiveness of treatment depends on the amount of time during the dosing interval ...
Fisher JF, Meroueh SO, Mobashery S (February 2005). "Bacterial resistance to beta-lactam antibiotics: compelling opportunism, ... Okada S, O'Brien JS (August 1969). "Tay-Sachs disease: generalized absence of a beta-D-N-acetylhexosaminidase component". 》 ... "Molecular basis of beta-lactamase induction in bacteria". 》Antimicrob. Agents Chemother.》 37 (2): 153-8. doi:10.1128/aac.37.2. ...
These bacterial enzymes rapidly destroy earlier-generation cephalosporins by breaking open the drug's beta-lactam chemical ring ... leading to antibiotic resistance. Though initially active against these bacteria, with widespread use of third-generation ... This group provides improved stability against certain beta-lactamase enzymes produced by Gram-negative bacteria. ... cephalosporins, some Gram-negative bacteria that produce extended-spectrum beta-lactamases (ESBLs) are even able to inactivate ...
Ang karaniwang mga opsyon ay kinabibilangan ng clindamycin, ang magkasamang beta-lactam na antibiyotiko at metronidazole, o ... "Community-Acquired Pneumonia: From Common Pathogens To Emerging Resistance". Emergency Medicine Practice. 7 (12).. Unknown ...
The substance has been reported to inhibit two antibiotic resistance carbapenemase proteins in bacteria, New Delhi metallo-beta ... The relative amount of these two toxins is dependent upon the pH of the growth medium, with lower pH favouring the lactam form ... The lactam can be hydrolyzed to aspergillomarasmine A by treating it with trifluoroacetic acid. Aspergillomarasmine A functions ... Anhydroaspergillomarasmine A, a lactam of aspergillomarasmine A, chemically called [1-(2-amino-2carboxyethyl)-6-carboxy-3- ...
... clindamycin and third generation cephalosporins while the other fusobacteria have varying degrees of resistance to beta-lactams ... Fusobacterium necrophorum is generally highly susceptible to beta-lactam antibiotics, metronidazole, ... Penicillin and penicillin-derived antibiotics can thus be combined with a beta-lactamase inhibitor such as clavulanic acid or ...
... or a beta-lactam antibiotic). Three classes of vancomycin-resistant S. aureus have emerged that differ in vancomycin ... Antibiotic resistance Drug resistance Methicillin-resistant Staphylococcus aureus (MRSA)(Vancomycin intermediate-resistant ... High-level vancomycin resistance in S. aureus has been rarely reported. In vitro and in vivo experiments reported in 1992 ... Strains of hVISA and VISA do not have resistant genes found in Enterococcus and the proposed mechanisms of resistance include ...
Frequent infusions of beta-lactam antibiotics without exceeding total daily dose would help to keep the antibiotics level above ... In case of people having high risk of being infected with multiple drug resistance organisms such as Pseudomonas aeruginosa, ... Giving beta-lactam antibiotics continuously may be better than giving them intermittently.[55] Access to therapeutic drug ... During critical illness, a state of adrenal insufficiency and tissue resistance to corticosteroids may occur. This has been ...
Since the discovery of the beta-lactam antibiotic penicillin, the rates of antimicrobial resistance have increased. Over time, ... Specific patterns of drug resistance or multi drug resistance may be noted, such as the presence of an extended-spectrum beta ... This resistance might be because a type of bacteria has intrinsic resistance to some antibiotics,[2] because of resistance ... Antibiotic susceptibility testing has occurred since the discovery of the beta-lactam antibiotic penicillin. Initial methods ...
Antibiotic resistanceEdit. Most Pseudomonas spp. are naturally resistant to penicillin and the majority of related beta-lactam ... Besides intrinsic resistance, P. aeruginosa easily develops acquired resistance either by mutation in chromosomally encoded ... Their resistance to most antibiotics is attributed to efflux pumps, which pump out some antibiotics before they are able to act ... Theories include: the bacteria might induce systemic resistance in the host plant, so it can better resist attack by a true ...
Falagas ME, Matthaiou DK, Vardakas KZ (December 2006). "Fluoroquinolones vs beta-lactams for empirical treatment of ... Antibiotic misuse and bacterial resistances[edit]. See also: Antibiotic misuse and Antibiotic resistance ... M Jacobs, Worldwide Overview of Antimicrobial Resistance. International Symposium on Antimicrobial Agents and Resistance 2005. ... Resistance to quinolones can evolve rapidly, even during a course of treatment. Numerous pathogens, including Escherichia coli ...
... beta-lactams, fluoroquinolones and aminoglycosides. It is very common for the resistance genes or entire resistance cassettes ... Often multiple beta-lactamase genes are found on the same plasmid hydrolyzing a wide spectrum of beta-lactam antibiotics. ESBL ... Multiple resistance genes are commonly arranged in the resistance cassettes. The antibiotic resistance genes found on the ... Plasmid-mediated resistance is the transfer of antibiotic resistance genes which are carried on plasmids. The plasmids can be ...
... a multiple drug resistance to beta-lactam antibiotics. Beta-lactam (β-lactam) antibiotics are a broad-spectrum group that ... modeled after MRSA's resistance to penicillin. Beta-lactam antibiotics permanently inactivate PBP enzymes, which are essential ... As a consequence of the inability of PBP2a to interact with β-lactam moieties, acquisition of mecA confers resistance to all β- ... mecA is a biomarker gene responsible for resistance to methicillin and other β-lactam antibiotics. After acquisition of mecA, ...
... it reduces the effect of any coincident synaptic input by reducing the electrical resistance of the cell's membrane. Shunting ... "GABA exerts protective and regenerative effects on islet beta cells and reverses diabetes". Proc. Natl. Acad. Sci. U.S.A. 108 ... β-Lactams (e.g., penicillins, cephalosporins, carbapenems). *Basmisanil. *Bemegride. *Bicyclic phosphates (TBPS, TBPO, IPTBO) ... "A point mutation in a Drosophila GABA receptor confers insecticide resistance". Nature. 363 (6428): 449-51. Bibcode:1993Natur. ...
Frequent infusions of beta-lactam antibiotics without exceeding total daily dose would help to keep the antibiotics level above ... In case of people having high risk of being infected with multiple drug resistance organisms such as Pseudomonas aeruginosa, ... Giving beta-lactam antibiotics continuously may be better than giving them intermittently.[50] Access to therapeutic drug ... During critical illness, a state of adrenal insufficiency and tissue resistance to corticosteroids may occur. This has been ...
... and inactivating beta-lactam antibiotics.[12] Although Bacteroides species are anaerobic, they are transiently aerotolerant[13] ... This high level of antibiotic resistance has prompted concerns that Bacteroides species may become a reservoir for resistance ... and resistance genes". The Journal of Antimicrobial Chemotherapy. 58 (6): 1160-7. doi:10.1093/jac/dkl420. PMID 17046967.. ... In general, Bacteroides are resistant to a wide variety of antibiotics-β-lactams, aminoglycosides, and recently many species ...
Resistance to antibioticsEdit. Capnocytophaga spp. are usually susceptible to antibiotics, but the emergence of beta-lactam- ... The high frequency of strains producing beta-lactamase limit the use of single beta-lactam antibiotics as first-line treatment ... This resistance is often linked to the production of beta- lactamases. Most beta-lactamases identified in Bacteroides, ... The CSP-1 beta- lactamaseEdit. In 2005, Handal et al. (2005b) identified a novel Ambler class A beta-lactamase called CSP-1 ...
Oral beta-lactam antibiotics are less effective than other available agents for treatment of pyelonephritis.[၁၀] ... In areas where there is a higher prevalence of fluoroquinolone resistance, it is useful to initiate treatment with a single ... The treatment regimen is selected based on local resistance data and the susceptibility profile of the specific infecting ...
Somewhat poorer activity is observed for the Klebsiella and Enterobacter species, with the MIC90 for extended spectrum beta- ... and Bacteroides fragilis strains having various resistance phenotypes". Antimicrobial Agents and Chemotherapy. 55 (5): 2390-4. ... β-lactams/. (inhibit PBP. cross-links). Penicillins. (Penams). Narrow. spectrum. β-lactamase sensitive. (1st generation). * ...
For treatment of infections caused by Gram-positive microorganisms in patients with serious allergies to beta-lactam ... Antibiotic resistance[edit]. Intrinsic resistance[edit]. A few Gram-positive bacteria are intrinsically resistant to vancomycin ... Acquired resistance[edit]. Evolution of microbial resistance to vancomycin is a growing problem, in particular, within ... Three main resistance variants have been characterised to date among resistant Enterococcus faecium and E. faecalis populations ...
... and Beta-Lactams". Pharmaceutics. 3 (4): 865-913. doi:10.3390/pharmaceutics3040865. PMC 3857062 . PMID 24309312.. ... Bacterial resistance[edit]. See also: Antibiotic abuse and Antibiotic resistance. As a result of its widespread use to treat ... M Jacobs, Worldwide Overview of Antimicrobial Resistance. International Symposium on Antimicrobial Agents and Resistance 2005. ... "Bacterial resistance prompts concern among health officials". 26 February 2009. Archived from the original on 5 March 2009.. ...
Beta lactamase inhibitors irreversibly bind to beta-lactamase preventing it from breaking down the beta-lactam rings on the ... "Penicillin G sodium salt Susceptibility and Resistance Data" (PDF). TOKU-E. Retrieved 4 March 2014.. ... Some bacteria produce enzymes that break down the beta-lactam ring, called beta-lactamases, which make the bacteria resistant ... has activity against beta-lactamase producing bacteria due to an acyl side chain that protects the beta-lactam ring from beta- ...
... they are unaffected by many common antibiotics such as penicillin or other beta-lactam antibiotics that target cell wall ... Mycoplasma gentialium has developed resistance to some antibiotics.[11] Mycoplasmae are associated with fetal respiratory ...
Most β-lactam antibiotics, including the penicillins, cephalosporins and monolactams contain sulfur.[34] ... Molten sulfur is sometimes still used for setting steel bolts into drilled concrete holes where high shock resistance is ... beta: 1.96 g/cm3 gamma: 1.92 g/cm3 when liquid (at m.p.). 1.819 g/cm3 ... all of the stable allotropes are excellent electrical insulators. ...
... is structurally distinct from both vancomycin, a glycopeptide antibiotic, and methicillin, a beta-lactam antibiotic ... The need to find new antibiotics to combat antibiotic resistance means that biologic and synthetic interest in bottromycin will ... especially given the rise of antibiotic resistance. The mechanism of action of bottromycin was confirmed nearly 20 years ...
In the past, the aminoglycosides have been used in conjunction with beta-lactam antibiotics in streptococcal infections for ... The recent emergence of infections due to Gram-negative bacterial strains with advanced patterns of antimicrobial resistance ... One of the most frequent combinations is ampicillin (a beta-lactam, or penicillin-related antibiotic) and gentamicin. Often, ... "Aminoglycosides: activity and resistance". Antimicrob. Agents Chemother. 43 (4): 727-37. PMC 89199. PMID 10103173.. .mw-parser ...
Beta-lactam antibiotics. *Enantiopure drugs. *Warld Heal Organisation essential medicines. *Phenols. Skauk't categeries: *ECHA ... This increases effectiveness bi reducin its susceptibility tae β-lactamase resistance.[1] ... Amoxicillin (INN), umwhile amoxycillin (BAN), an abbreviatit amox, is a moderate-spectrum, bacteriolytic, β-lactam antibiotic ... nor ither β-lactam antibiotics. Amoxicillin is ane o the maist common antibiotics prescribed for childer. The drug first acame ...
6-Methoxymellein is a dihydroisocoumarin and a phytoalexin induced in carrot slices by UV-C,[91] that allows resistance to ... "Lead identification of conformationally restricted β-lactam type combretastatin analogues: Synthesis, antiproliferative ... Mercier, J.; Arul, J.; Ponnampalam, R.; Boulet, M. (1993). "Induction of 6-Methoxymellein and Resistance to Storage Pathogens ... Hoffman, R.; Heale, J. B. (1987). "Cell death, 6-methoxymellein accumulation, and induced resistance to Botrytis cinerea in ...
NDM-1 is a newly identified enzyme conveying bacterial resistance to a broad range of beta-lactam antibacterials.[74] The ... Plasmids that carry several different resistance genes can confer resistance to multiple antibacterials.[72] Cross-resistance ... Resistance and modifying agentsEdit. One strategy to address bacterial drug resistance is the discovery and application of ... Resistance modifying agents are capable of partly or completely suppressing bacterial resistance mechanisms.[136] For example, ...
The aim of this study was to investigate beta-lactam resistance in Escherichia coli and Klebsiellaspp. blood culture isolates ... The aim of this study was to investigate beta-lactam resistance inEscherichia coli andKlebsiella spp. blood culture isolates in ... Beta-lactam resistance amongEscherichia coli andKlebsiella species blood culture isolates in Finnish hospitals. ... Payne DJ, Amyes SGB: Transferable resistance to extended-spectrum β-lactams: a major threat or a minor inconvenience? Journal ...
... increased β-lactam resistance, while four other LTs (MltD, MltD2, MltF and Slt2) seemed dispensable to β-lactam resistance. The ... increased β-lactam resistance, while four other LTs (MltD, MltD2, MltF, and Slt2) seemed dispensable to β-lactam resistance. ... from both double LT mutants further increased the resistance to β-lactams. Notably, all increased β-lactam resistance ... The double LT mutants ΔmltBΔmltB2 and ΔsltYΔmltB2 had β-lactam resistance stronger than any of the single mutants. Deletion of ...
Extended broad-spectrum beta-lactamases conferring transferable resistance to newer beta-lactam agents in Enterobacteriaceae: ... three beta-lactamases mediating cefotaxime resistance were identified as SHV-2 (isoelectric point [pI] 7.6), CTX-1 (pI 6.3), ... "extended broad-spectrum beta-lactamases" (EBS-Bla). The enzymes conferred to derivatives a high level of resistance to ... resistance to cefotaxime in clinical isolates of Enterobacteriaceae involved only species producing inducible class 1 beta- ...
... to imipenem and exhibiting the main patterns of susceptibility to other beta-lactam agents (wild type pattern, penicillinase ... whether resistance to carbapenems affects the level of resistance to other beta-lactam agents and, conversely, if resistance to ... Lack of additive effect between mechanisms of resistance to carbapenems and other beta-lactam agents in Pseudomonas aeruginosa ... Thus, when several mechanisms of resistance to beta-lactam agents are present in the same strain of Pseudomonas aeruginosa, ...
Low-affinity penicillin-binding protein associated with beta-lactam resistance in Staphylococcus aureus.. B J Hartman, A Tomasz ... Low-affinity penicillin-binding protein associated with beta-lactam resistance in Staphylococcus aureus. ... Low-affinity penicillin-binding protein associated with beta-lactam resistance in Staphylococcus aureus. ... Low-affinity penicillin-binding protein associated with beta-lactam resistance in Staphylococcus aureus. ...
... encodes a metallo-β-lactamase that inactivates all β-lactams except aztreonam. This bla(NDM-1) gene has been identified in ... Does broad-spectrum beta-lactam resistance due to NDM-1 herald the end of the antibiotic era for treatment of infections caused ... This gene has been identified in strains that possess other resistance mechanisms contributing to their multidrug resistance ... 1 Service de Bactériologie-Virologie, INSERM U914 Emerging Resistance to Antibiotics, Hôpital de Bicêtre, Assistance Publique/ ...
... coli suggests that it may be an intermediate stage in the development of full antibiotic resistance, representing a shift in ... A study of heteroresistance to broad range of beta-lactam antibiotics in clinical isolates of E. ... our understanding of the evolution of antibiotic resistance. ...
Conclusion: The acquisition of resistance of Pseudomonas aeruginosa to beta lactam antibiotics in community infections among ... Describe resistance to beta lactam antibiotics of Pseudomonas aeruginosa in community infection within HIV-1 infected persons. ... Resistance to Beta Lactam Antibiotics of Pseudomonas aeruginosa Isolated in Community Infections within HIV Infected Persons in ... Objective: Describe resistance to beta lactam antibiotics of Pseudomonas aeruginosa in community infection within HIV-1 ...
Salmonella isolates with reduced susceptibility to beta-lactams (n = 43) were tested for genes encoding for beta-lactamase ... were also resistant to at least one of the beta-lactam antimicrobials. Acquisition of blaTEM was the principal beta-lactamase ... Further study on extended spectrum beta-lactamase and quinolone resistance mechanisms in other gram negative pathogens is ... as well as plasmid mediated quinolone resistance (PMQR) genes using PCR and sequencing. Beta-lactamase genes (bla) were ...
Antimicrobial resistance is a serious global issue. Since only empirical therapy with antibiotics is widely followed in India, ... Prevalence Of Resistance To Beta-Lactam Antibiotics Among Respiratory Tract Isolates In A Hospital Situation. Author(s): K ... Antimicrobial resistance is a serious global issue. Since only empirical therapy with antibiotics is widely followed in India, ... A study of the prevalence of antimicrobial resistance among respiratory tract isolates was conducted in a secondary care ...
... proteins 2b and 2x of Streptococcus pneumoniae are primary resistance determinants for different classes of beta-lactam ... proteins 2b and 2x of Streptococcus pneumoniae are primary resistance determinants for different classes of beta-lactam ... proteins 2b and 2x of Streptococcus pneumoniae are primary resistance determinants for different classes of beta-lactam ... proteins 2b and 2x of Streptococcus pneumoniae are primary resistance determinants for different classes of beta-lactam ...
Transition from resistance to hypersusceptibility to beta-lactam antibiotics associated with loss of a low-affinity penicillin- ... Transition from resistance to hypersusceptibility to beta-lactam antibiotics associated with loss of a low-affinity penicillin- ... Transition from resistance to hypersusceptibility to beta-lactam antibiotics associated with loss of a low-affinity penicillin- ... Transition from resistance to hypersusceptibility to beta-lactam antibiotics associated with loss of a low-affinity penicillin- ...
Given that beta-lactam and trimethoprim resistance arise from different mechanisms and that the dhfR and folP loci are not ... 1. Co-occurrence of co-trimoxazole and beta-lactam resistance phenotypes. Note that the association is significant for the ... However, levels of beta-lactam resistance have generally remained stable post-vaccine introduction [21], [45], [46], which has ... Beta-lactam specificity of resistance mutations. As some of the variants detected by our study are known to affect the binding ...
Quantification of genes encoding resistance to aminoglycosides, beta-lactams and tetracyclines in wastewater environments by ... beta-lactams (mecA), and tetracyclines (tetA and tetB), for use in wastewater environments. The developed assays were applied ... In this study real-time PCR assays, based on the LUX-technique, were developed for quantification of genes mediating resistance ... were shown to be fast and reproducible tools for detection and quantification of the four genes encoding antibiotic resistance ...
... exhibited broad-spectrum beta-lactam resistance patterns. These organisms collectively produced three classes of beta- ... The rate of resistance to broad-spectrum beta-lactams among isolates of the Enterobacteriaceae is increasing in children in ... significant isolates of the Enterobacteriaceae were screened for patterns of broad-spectrum resistance to beta-lactams. The ... and the resistance is driven largely by plasmid-mediated AmpC beta-lactamases. These data have important implications for ...
The need of continuous monitoring of beta-lactam susceptibility and a global system for molecular surveillance of rPBP3 strains ... The prevalence of clinical PBP3-mediated resistance to ampicillin was 9%, compared to 2.5% three years earlier. Group II low- ... Beta-lactam resistance in Haemophilus influenzae due to ftsI mutations causing altered penicillin-binding protein 3 (PBP3) is ... Beta-lactams are first-line drugs for treatment of H. influenzae infections but resistance may develop due to transferable beta ...
... represents a novel resistance problem and one which may increase with increased use of newer antipseudo-monal beta-lactams. ... resistance could not be attributed to beta-lacta-mase production and was considered to be intrinsic. The unusual antibiogram in ... 35 produced plasmid-mediated beta-lactamases known to be active against carbenicillin and seven produced unusual beta- ... These represented the most resistant organisms of 1866 isolates collected during a national survey of antibiotic resistance in ...
... resistance. Because of the popularity of beta-lactam drugs, certain bacteria have been able to develop counter- ... A beta-lactam ring (β-lactam) is a lactam with a heteroatomic ring structure, consisting of three carbon atoms and one nitrogen ... become resistant against beta-lactam antibiotics by expressing beta-lactamase.. History. The first synthetic β-lactam was ... As a response to bacterial resistance to beta-lactam drugs, there are drugs, such as Augmentin/CLA, that are designed to ...
Pseudomonas pseudomallei resistance to beta-lactam antibiotics due to alterations in the chromosomally encoded beta-lactamase. ... Pseudomonas pseudomallei resistance to beta-lactam antibiotics due to alterations in the chromosomally encoded beta-lactamase. ... Quantifying antibiotic impact on within-patient dynamics of extended-spectrum beta-lactamase resistance ... Antimicrobial resistance in Cambodia * "I cant read and dont understand": Health literacy and messaging in a migrant ...
PBP 4, although not essential for survival, has been associated with low-level resistance to beta-lactam antibiotics. To ... These data indicate that PBP 4 is a relatively unimportant target of beta-lactams not only in methicillin-susceptible but also ... determine its contribution to survival of Staphylococcus aureus cells exposed to beta-lactams, the PBP 4 gene (pbp4) was ... Impact of mecA promoter mutations on mecA expression and beta-lactam resistance levels.. Miriam Ender, Nadine McCallum, ...
Lactams. Aztreonam. Amoxicillin-Potassium Clavulanate Combination. beta-Lactams. Antibiotics, Antitubercular. Trimethoprim. ... The continuous increase in the bacterial resistance rate and the slow arrival of new therapeutic options have turned into an ... Drug: Antipseudomonal beta-lactam antibiotic Drug: De-escalation(short-spectrum antibiotic) Phase 3 ... Experimental: Antipseudomonal beta-lactam antibiotic *Ampicillin 2g IV/6h. *Trimethoprim/sulfamethoxazole 160/800 mg IV/8 -12h ...
Resistance to beta-lactam antibiotics is mediated by at least one of three resistance mechanisms: inactivating enzymes (BL); ... Resistance to beta-lactam agents among non-Bacteroides anaerobes is variable but is generally lower than the B. fragilis group ... Beta-lactams are still useful agents for the treatment of anaerobic infections, even though significant resistance has been ... The B. fragilis group has the highest prevalence of resistance to beta-lactams as almost all (more than 97%) of B. fragilis ...
Resistance to beta lactam antibiotics NON-BILLABLE Non-Billable Code Non-Billable means the code is not sufficient ... ICD-10-CM Alphabetical Index References for Z16.1 - Resistance to beta lactam antibiotics The ICD-10-CM Alphabetical Index ... resistance to beta lactam antibiotics in more detail. ... Z16.1 Resistance to beta lactam antibiotics NON-BILLABLE * * ... beta lactamase (ESBL) resistance * BILLABLE Z16.19 Resistance to other specified beta lactam antibiotics ...
In vitro and in vivo activity of amoxicillin and penicillin G alone or combined with a penicillinase inhibitor (clavulanate) were tested against five isogenic pairs of methicillin-resistant Staphylococcus aureus (MRSA) producing or not producing penicillinase. Loss of the penicillinase plasmid caused an eight times or greater reduction in the MICs of amoxicillin and penicillin G (from greater than or equal to 64 to 8 micrograms/ml), but not of the penicillinase-resistant drugs methicillin and cloxacillin (greater than or equal to 64 micrograms/ml). This difference in antibacterial effectiveness correlated with a more than 10 times greater penicillin-binding protein 2a affinity of amoxicillin and penicillin G than of methicillin and a greater than or equal to 90% successful amoxicillin treatment of experimental endocarditis due to penicillinase-negative MRSA compared with cloxacillin, which was totally ineffective (P less than .001). Amoxicillin was also effective against penicillinase-
Beta-lactam antibiotics synonyms, Beta-lactam antibiotics pronunciation, Beta-lactam antibiotics translation, English ... n. Any of a class of broad-spectrum antibiotics, such as the penicillins and the cephalosporins, that contain a beta-lactam ... Reversing [beta]-lactam antibiotic resistance of Staphylococcus aureus with galangin from Alpinia officinarum Hance and ... Related to Beta-lactam antibiotics: beta-lactamase, Aminoglycosides beta-lactam antibiotic. n.. Any of a class of broad- ...
... consider using a code with a higher level of specificity for a diagnosis of resistance to beta lactam antibiotics. ... BILLABLE CODE - Use Z16.10 for Resistance to unspecified beta lactam antibiotics. * BILLABLE CODE - Use Z16.11 for Resistance ... Specific Coding for Resistance to beta lactam antibiotics. Non-specific codes like Z16.1 require more digits to indicate the ... Consider using any of the following ICD-10 codes with a higher level of specificity when coding for resistance to beta lactam ...
beta-lactam synonyms, beta-lactam pronunciation, beta-lactam translation, English dictionary definition of beta-lactam. n. 1. A ... formed by intramolecular condensation of an amino acid in which the amino group is located at the beta... ... showed resistance to several beta-lactam and non-beta-lactam antibiotics, including colistin.. Extended-spectrum beta- ... Related to beta-lactam: beta-lactamase, Beta-lactam Ring. be·ta-lac·tam. (bā′tə-lăk′təm, bē′-). n.. 1. A lactam composed of a ...
Home » Infectious Disease » Zoonosis, Emerging Disease, and Drug Resistance » Novel Mechanisms of Beta-Lactam Resistance in ... lactam Resistance; and 2) that GdpP contributes to Resistance via a signaling pathway that up-regulates expression of pbp4. Two ... lactam Resistance in Staphylococcus aureus. This new type of Resistance was identified during experiments in which methicillin ... better antibiotics to overcome Resistance. We have discovered a Novel mechanism of Resistance to ?-lactams that is independent ...
Home » Noncommunicable and/or Chronic Disease » Novel Mechanisms of Beta-Lactam Resistance in Staph Aureus ... lactam resistance; and 2) that GdpP contributes to resistance via a signaling pathway that up-regulates expression of pbp4. Two ... lactam resistance in Staphylococcus aureus. This new type of resistance was identified during experiments in which methicillin ... Aim 1: To determine the mechanism by which mutations in pbp4 confer high-level ?-lactam resistance. pbp4 missense mutations ...
... but whether antibiotic use is responsible for the increase in drug resistance is not known. ... However, oral beta-lactam use was associated with an increased risk of PRSp carriage (odds ratio [OR], 3.0; 95% confidence ... Our results suggest that a low daily dose and a long duration of treatment with an oral beta-lactam contribute to the selective ... Low dosage and long treatment duration of beta-lactam: risk factors for carriage of penicillin-resistant Streptococcus ...
  • blood culture isolates were collected from hospitals throughout Finland and their susceptibility to beta-lactam antibiotics studied. (springer.com)
  • Beta-lactam antibiotics are the most widely used group of antibiotics, they target the penicillin-binding proteins (PBPs), eventually disrupting the peptidoglycan synthesis. (frontiersin.org)
  • Expression of β-lactamases encoded by the chromosome is often inducible by β-lactam antibiotics. (frontiersin.org)
  • 1 Service de Bactériologie-Virologie, INSERM U914 Emerging Resistance to Antibiotics, Hôpital de Bicêtre, Assistance Publique/Hôpitaux de Paris, Faculté de Médecine et Université Paris-Sud, K.-Bicêtre, France. (nih.gov)
  • Objective: Describe resistance to beta lactam antibiotics of Pseudomonas aeruginosa in community infection within HIV-1 infected persons. (scirp.org)
  • Conclusion: The acquisition of resistance of Pseudomonas aeruginosa to beta lactam antibiotics in community infections among HIV-1 infected person incentives controls and promotes the rational use of antibiotics. (scirp.org)
  • Since only empirical therapy with antibiotics is widely followed in India, it is helpful that the treating doctors haw information on the prevalence of microbial resistance to the commonly prescribed antibiotics for various infections. (ijpsonline.com)
  • Penicillin-binding proteins 2b and 2x of Streptococcus pneumoniae are primary resistance determinants for different classes of beta-lactam antibiotics. (asm.org)
  • Transition from resistance to hypersusceptibility to beta-lactam antibiotics associated with loss of a low-affinity penicillin-binding protein in a Streptococcus faecium mutant highly resistant to penicillin. (asm.org)
  • In addition, it was highly susceptible to other beta-lactams but remained as susceptible as R40 and PS to antibiotics of a different mechanisms of action. (asm.org)
  • Antibiotic treatment has become more difficult, especially that involving the group of beta-lactam antibiotics where resistance has developed rapidly. (prolekare.cz)
  • The mechanisms of resistance to beta-lactam antibiotics in 191 isolates of Pseudomonas aeruginosa were examined. (microbiologyresearch.org)
  • The beta-lactam ring is part of the structure of several antibiotic families, the principal ones being the penicillins , cephalosporins , carbapenems , and monobactams , which are, therefore, also called beta-lactam antibiotics . (princeton.edu)
  • Bacteria can, however, become resistant against beta-lactam antibiotics by expressing beta-lactamase . (princeton.edu)
  • Pseudomonas pseudomallei resistance to beta-lactam antibiotics due to alterations in the chromosomally encoded beta-lactamase. (tropmedres.ac)
  • Effect of disruption of Staphylococcus aureus PBP4 gene on resistance to beta-lactam antibiotics. (semanticscholar.org)
  • Penicillin-binding proteins (PBPs) mediate susceptibility to beta-lactam antibiotics. (semanticscholar.org)
  • PBP 4, although not essential for survival, has been associated with low-level resistance to beta-lactam antibiotics. (semanticscholar.org)
  • To code a diagnosis of this type, you must use one of the four child codes of Z16.1 that describes the diagnosis 'resistance to beta lactam antibiotics' in more detail. (icd.codes)
  • Z16.1 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of resistance to beta lactam antibiotics. (icdlist.com)
  • Any of a class of broad-spectrum antibiotics, such as the penicillins and the cephalosporins, that contain a beta-lactam ring. (thefreedictionary.com)
  • OP0595, via its unique mode of action, restores the efficacy of beta-lactam antibiotics against infections caused by beta-lactamase producing, antibiotic-resistant bacteria. (thefreedictionary.com)
  • NYSE MKT: SYN), a clinical stage company focused on developing therapeutics to protect the gut microbiome while targeting pathogen specific diseases, announced positive topline results from the first Phase 2a study of SYN-004, the Company's candidate designed to protect the gut microbiome from the unintended effects of certain commonly used intravenous (IV) beta-lactam antibiotics for the prevention C. (thefreedictionary.com)
  • com)-- Bioo Scientific's MaxSignal[R] Beta-Lactam ELISA Test Kit has been validated for the screening of a wide range of beta-lactam antibiotics including ampicillin, penicillin G, amoxicillin, azlocillin, piperacillin, nafcillin, cloxacillin, oxacillin, cefoperazone, ceftiofur and other beta-lactams in a number of food matrices. (thefreedictionary.com)
  • Like most carbapenemases, KPCs are enzymes which inactivate all beta-lactam antibiotics , including carbapenems, penicillins, cephalosporins and monobactams. (thefreedictionary.com)
  • Analysis of twelve beta-lactam antibiotics in human plasma by HPLC with ultraviolet detection. (thefreedictionary.com)
  • Lot 2 - antibiotics (Other beta-lactam antibiotics third generation cephalosporins, other beta-lactam antibiotics cephalosporins fourth generation) - 21. (thefreedictionary.com)
  • and Enterome Bioscience SA have entered into an agreement to conduct metagenomic research on the effects of beta-lactam antibiotics on the gastrointestinal microflora (microbiome) of human patients. (thefreedictionary.com)
  • To investigate the development of resistance to beta-lactam antibiotics , one group followed 132 intensive care unit (ICU) patients over a three-year period. (thefreedictionary.com)
  • Baicalin synergy with beta-lactam antibiotics against methicillin-resistant Staphylococcus aureus and other beta-lactam-resistant strains of S. (thefreedictionary.com)
  • and, eventually, better antibiotics to overcome Resistance. (ucsf.edu)
  • lactam antibiotics. (ucsf.edu)
  • Hahn and colleagues recruited 20 patients between 1 to 21 years of age who were treated for APEs with beta-lactam antibiotics at Children's National. (thefreedictionary.com)
  • Beta-lactam antibiotics induce a lethal malfunctioning of the bacterial cell wall synthesis machinery. (thefreedictionary.com)
  • Summary: New Delhi [India], Dec 17 (NewsVoir): Effective December 10, 2018 Centrient Pharmaceuticals is the new name for DSM Sinochem Pharmaceuticals, the leading manufacturer of beta-lactam antibiotics and a provider of next-generation statins and anti-fungals. (thefreedictionary.com)
  • Synthetic Biologics, in consultation with the FDA, has confirmed the key elements of the Phase 3 clinical program to support a marketing application for ribaxamase, the company's first-in-class oral enzyme designed to degrade certain intravenous beta-lactam antibiotics within the gastrointestinal tract to prevent microbiome damage, Clostridium difficile infection, overgrowth of pathogenic organisms and the emergence of antimicrobial resistance. (thefreedictionary.com)
  • Beta lactam is a class of broad-spectrum antibiotics, consisting of all antibiotic agents that contain a beta-lactam ring in their molecular structures. (thefreedictionary.com)
  • QJRZ00000000), showed resistance to several beta-lactam and non-beta-lactam antibiotics, including colistin. (thefreedictionary.com)
  • SYN-004 (ribaxamase) is designed to protect the gut microbiome from the effects of certain commonly used intravenous beta-lactam antibiotics for the prevention of C. (thefreedictionary.com)
  • ATLANTA -- With the help of a pharmacist and the electronic health records system, Rochester (N.Y.) General Hospital ruled out penicillin allergies in 47 of 50 adult inpatients, and successfully transitioned them from second-line antibiotics to less expensive and more effective beta-lactam options. (thefreedictionary.com)
  • According to Clinical and Laboratory Standards Institute (CLSI) recommendations, susceptibilities of isolates to various antibiotics were investigated by disk diffusion and agar dilution method, and beta-lactamase enzymes were detected by isoelectric focusing (IEF) method. (istanbul.edu.tr)
  • Beta-lactam (BL) antibiotics hypersensitivity is common in children. (bioportfolio.com)
  • Nonsusceptibility of bacteria to the action of the beta-lactam antibiotics. (bioportfolio.com)
  • Mechanisms responsible for beta-lactam resistance may be degradation of antibiotics by BETA-LACTAMASES, failure of antibiotics to penetrate, or low-affinity binding of antibiotics to targets. (bioportfolio.com)
  • The most common form of resistance to β-lactam antibiotics is the expression of various β-lactamase enzymes capable of hydrolyzing the β-lactam ring of β-lactam drugs, rendering them ineffective. (pnas.org)
  • In efforts to restore the efficacy of β-lactam antibiotics, β-lactamases have also been targeted with a variety of inhibitors ( 5 , 6 ). (pnas.org)
  • While some loci appear to be universal resistance determinants, contributing equally to non-susceptibility for at least two classes of beta-lactam antibiotics, some play a larger role in resistance to particular antibiotics. (cdc.gov)
  • Capable of causing invasive infections, Streptococcus pyogenes (Group A strep) has been susceptible to beta-lactam antibiotics for more than a half century. (reliasmedia.com)
  • While resistance has been seen in Group A strep for clindamycin and other antibiotics, [it] has remained susceptible for beta-lactams for over 50 years," she says. (reliasmedia.com)
  • Other bacteria that are resistant to beta-lactams like penicillin and ampicillin have acquired a way to protect the cell walls these antibiotics typically bind to and break down. (reliasmedia.com)
  • However, the case was unusual in that it represents the first report of emerging Group A strep resistance to the time-honored beta-lactam class of antibiotics. (reliasmedia.com)
  • Patient A repeatedly received beta-lactam and other antibiotics courses, including ampicillin," she says. (reliasmedia.com)
  • Various species of gram-negative organisms isolated from surgical site infections showed complex antibiograms to various beta-lactams , even to the new generation of antibiotics . (bvsalud.org)
  • This evidence suggests that there has been a molecular evolution of beta-lactamase genes to a great extent in Korea , possibly due to indiscriminate use of antibiotics . (bvsalud.org)
  • Antibiotics and antibiotic resistant bacteria enter wastewater treatment plants (WWTPs), an environment where resistance genes can potentially spread and exchange between microbes. (ku.dk)
  • Objectives To systematically review studies investigating the prevalence of antibiotic resistance in urinary tract infections caused by Escherichia coli in children and, when appropriate, to meta-analyse the relation between previous antibiotics prescribed in primary care and resistance. (bmj.com)
  • Pooled percentage prevalence of resistance to the most commonly used antibiotics in children in primary care, stratified by the OECD (Organisation for Economic Co-operation and Development) status of the study country. (bmj.com)
  • Random effects meta-analysis was used to quantify the association between previous exposure to antibiotics in primary care and resistance. (bmj.com)
  • Conclusions Prevalence of resistance to commonly prescribed antibiotics in primary care in children with urinary tract infections caused by E coli is high, particularly in countries outside the OECD, where one possible explanation is the availability of antibiotics over the counter. (bmj.com)
  • Routine use of antibiotics in primary care contributes to antimicrobial resistance in children, which can persist for up to six months after treatment. (bmj.com)
  • Molecular processes such cell wall synthesis and recycling, for example, have become better understood through the study of how antibiotics affect beta-lactam development through the antibiosis relationship and interaction of the particular drugs with the bacteria subjected to the compound. (wikipedia.org)
  • Many organisms produce beta-lactamase enzymes that can destroy these antibiotics. (thefreedictionary.com)
  • This is a common cause of bacterial resistance to antibiotics. (thefreedictionary.com)
  • This resistance is not only for beta-lactam antibiotics , but also extends to other antibiotic classes through the same plasmid-carrying resistance genes and infection of these bacteria may result in therapeutic failure.2 Beta lactamases cause resistance to beta-lactam agents and are produced by different aerobic gram-negative bacteria (AGNB).3 Hospitals and nursing homes are found as the main reservoirs of ESBLs producing bacteria. (thefreedictionary.com)
  • Hahn and colleagues suspect that patients who often don't achieve therapeutic blood levels of antibiotics may be genetically predisposed to metabolize beta-lactam antibiotics quickly. (thefreedictionary.com)
  • The Cedars-Sinai scientists explain that beta-lactam antibiotics kill normal staph bacteria by inactivating their cell-wall-making enzymes. (thefreedictionary.com)
  • 2) ESBLs are plasmid-mediated enzymes (3) and have the ability to hydrolyze diverse types of the newer beta-lactam antibiotics , including extendedspectrum cephalosporins of the 3rd and 4th generation (e.g. (thefreedictionary.com)
  • This is in contrast with the rash observed in patients who received beta-lactam antibiotics , mainly ampicillin or amoxicillin, which is associated with a hypersensitivity reaction to the antibiotic (1) and it is usually pruritic and prolonged. (thefreedictionary.com)
  • In summary, C and ECg enhanced the antibacterial effect of β-lactam antibiotics against MRSA in vitro and in vivo , which might be related to the increased accumulation of antibiotics within MRSA via suppression of important efflux pumps' gene expression. (mdpi.com)
  • In fact, MRSA bacteria are resistant to nearly all types of antibiotics, especially β-lactam antibiotics [ 2 ]. (mdpi.com)
  • The main resistance mechanisms of MRSA to the β-lactam antibiotics are a large expression of β-lactamase to destroy β-lactams by hydrolysis, an acquisition of the mecA gene to encode the penicillin-binding protein 2a (PBP2a) with low affinity to β-lactam antibiotics [ 3 ], and an expression of efflux pumps to extrude antibiotics or other toxic agents from the pathogen [ 4 ]. (mdpi.com)
  • The beta lactam antibiotics (e.g. penicillins, cephalosporins) and the aminoglycosides (e.g. gentamicin) kill bacteria by different means. (cochrane.org)
  • Combining a beta lactam with an aminoglycoside could, therefore, result in more effective treatment of patients with severe infection but with the side effects of both antibiotics. (cochrane.org)
  • Our objectives were to compare beta lactam monotherapy versus beta lactam-aminoglycoside combination therapy in patients with sepsis and to estimate the rate of adverse effects with each treatment regimen , including the development of bacterial resistance to antibiotics. (cochrane.org)
  • The AY-lactam antibiotics are inactivated by Beta-lactamases that hydrolyze the amide bond that exists in the beta-lactam ring , disrupting the ring structure and make the antibiotics nonfunctional against bacteria.NDM-1 is a broad-spectrum AY-lactamasewhich has the ability to inactivate most of the AY- lactam antibiotics (Walsh et al. (thefreedictionary.com)
  • This has a lethal effect on bacteria, although any given bacteria population will typically contain a subgroup that is resistant to β-lactam antibiotics. (wikipedia.org)
  • β-lactam derived antibiotics can be considered as one of the most important antibiotic classes but prone to clinical resistance. (wikipedia.org)
  • This strain is further increased by fusion to a second ring, as found in most β-lactam antibiotics. (wikipedia.org)
  • Although antibiotics might not be harmful to our health in small quantities, over time they may lead to antibiotic resistance. (popsci.com)
  • The device tests for the antibiotics tetracycline and beta-lactam. (popsci.com)
  • Beta-lactam antibiotics, amoxicillin/clavulanate, cefaclor, cefdinir, and cefpodoxime are not recommended for initial treatment because of concerns about resistance. (aafp.org)
  • Most β-lactam antibiotics are ineffective against Mycobacterium tuberculosis due to the microbe's innate resistance. (asm.org)
  • The carbapenem class of β-lactam antibiotics has been proposed as one such class of drugs. (asm.org)
  • They are members of the β-lactam antibiotics, which are some of the most powerful and successful achievements in modern science. (wikipedia.org)
  • It is known that the use of sub-therapeutic doses of antibiotics in animals intended for food production promotes mutations of some chromosomal genes such as gyrA-parC and mphA, which are responsible for quinolone and azithromycin resistance, respectively. (intechopen.com)
  • Unfortunately, within 50-60 years, these successes of medical science were starting to fade as micro-organisms began to develop resistance toward antibiotics ( 10 - 12 ). (frontiersin.org)
  • NDM is a type of MBL produced by the bacteria that makes it resistant to a broad range of beta-lactam antibiotics including the carbapenem group except aztreonam [ 2 ]. (hindawi.com)
  • no one seriously disputes that resistance emerges whenever antibiotics exert selective pressure on bacteria, killing the vulnerable and opening an ecological niche into which the surviving not-vulnerable can expand. (wired.com)
  • fingerprinting, PFGE and MLVA) and had the same resistance pattern, susceptible to antibiotics that were not beta-lactams (penicillins and cephalosporins). (wired.com)
  • There has been an explosion of resistance to antibiotics, whereby our entire arsenal of antibiotics is gradually losing effectiveness. (keystonesymposia.org)
  • Weak or elderly patients in particular can suffer from persistent infections, which have to be treated with other antibiotics, leading to yet more resistance. (newscientist.com)
  • More promisingly, some natural products could reverse the resistance of bacteria to the antibiotics, making the target bacteria susceptible to these drugs again. (intechopen.com)
  • The most recent concern is the emergence of Gram-negative bacilli expressing the New Delhi metallo-beta-lactamase (NDM-1), which are resistant to all available antibiotics. (smi-online.co.uk)
  • Antimicrobial resistance constitutes a global health problem, while the discovery and development of novel antibiotics is stagnating. (ugent.be)
  • Since resistance development is unavoidable with conventional antibiotics that target bacterial viability, it is vital to develop alternative treatment options on top. (ugent.be)
  • Smith DeWaal and Vaughn Grooters [14] statement that there has been a significant increase in sales and distribution of the highly important classes of antibiotics (tetracyclines, beta-lactams and sulfonamides) frequently used for restorative and prophylactic purposes in food-producing animals. (cylch.org)
  • Often multiple beta-lactamase genes are found on the same plasmid hydrolyzing a wide spectrum of beta-lactam antibiotics. (wikipedia.org)
  • ESBL enzymes can hydrolyze all beta-lactam antibiotics, including cephalosporins, except for the carpabepenems. (wikipedia.org)
  • In addition, since the plasmids that carry ESBL genes also commonly encode resistance determinants for many other antibiotics, ESBL strains are often resistant to many non-beta-lactam antibiotics as well, leaving very few options for the treatment. (wikipedia.org)
  • NDM-1 is an enzyme that makes bacteria resistant to a broad range of beta-lactam antibiotics. (wikipedia.org)
  • Carbapenems are a class of beta-lactam antibiotics that are capable of killing most bacteria by inhibiting the synthesis of one of their cell wall layers. (wikipedia.org)
  • However, the blaNDM-1 gene produces NDM-1, which is a carbapenemase beta-lactamase - an enzyme that hydrolyzes and inactivates these carbapenem antibiotics. (wikipedia.org)
  • Carbapenemases are particularly dangerous resistance mechanisms, since they can inactivate a wide range of different antibiotics. (wikipedia.org)
  • As previously, the bacteria were fully resistant to all the aminoglycoside, β-lactam, and quinolone antibiotics, but were susceptible to tigecycline and colistin. (wikipedia.org)
  • Synergy between imipenem or meropenem and BRL 42715 was observed for all of the strains, demonstrating the role of cephalosporinase in carbapenem resistance. (nih.gov)
  • Within each pattern of susceptibility, the mean MICs of beta-lactam agents other than carbapenems were similar, whether the strains were susceptible or resistant to imipenem. (nih.gov)
  • Conversely, the mean MICs of imipenem or meropenem for either the imipenem-resistant or the imipenem-susceptible strains were similar, regardless of the susceptibility of these strains to the other beta-lactam agents. (nih.gov)
  • This gene has been identified in strains that possess other resistance mechanisms contributing to their multidrug resistance patterns. (nih.gov)
  • The affinity of individual PBPs for the beta-lactams tested was the same in all the strains. (asm.org)
  • The need of continuous monitoring of beta-lactam susceptibility and a global system for molecular surveillance of rPBP3 strains is underlined. (biomedcentral.com)
  • in 131 strains, resistance could not be attributed to beta-lacta-mase production and was considered to be intrinsic. (microbiologyresearch.org)
  • Selection of strains with this last mechanism represents a novel resistance problem and one which may increase with increased use of newer antipseudo-monal beta-lactams. (microbiologyresearch.org)
  • The most active beta-lactam agents against anaerobic bacteria are the carbapenems (imipenem, meropenem, and ertapenem) with resistance of less than 0.2% of B. fragilis group isolates (15,20,43), and the combinations of a beta-lactam agent with a BL inhibitor (ampicillin/ sulbactam, ticarcillin/clavulanate, and piperacillin/tazobactam) where less than 4% of B. fragilis group strains were resistant in 2003 (18). (rrnursingschool.biz)
  • However, strains of non-BL-resistant Bacteroides distasonis frequently have higher MICs for all beta-lactam-BL inhibitor combinations. (rrnursingschool.biz)
  • This new type of Resistance was identified during experiments in which methicillin- susceptible S. aureus strains were passaged in the presence of each of the two so-called "fifth generation" anti-MRSA Cephalosporins, ceftobiprole and ceftaroline. (ucsf.edu)
  • A chemically tweaked version of one of these molecules made 82 percent of tested MRSA strains vulnerable to a beta-lactam antibiotic. (thefreedictionary.com)
  • OXA beta-lactamases have increasingly been reported in clinical strains of P.aeruginosa from various geographical origins. (istanbul.edu.tr)
  • This study was aimed to investigate the antibiotic susceptibility of various P.aeruginosa clinical strains and to define the beta-lactamase enzymes leading to resistance. (istanbul.edu.tr)
  • Phenotypical investigation of metallo-beta-lactamase enzyme in these strains by MBL E-test method did not reveal a positive result. (istanbul.edu.tr)
  • Antibiotic resistance mechanisms in P.aeruginosa strains seems to be complex. (istanbul.edu.tr)
  • Determination of the resistance mechanisms and antibiotic susceptibility rates in P.aeruginosa will guide the proper antimicrobial therapy, reducing the emergence of resistant strains. (istanbul.edu.tr)
  • Finally, a 5-kb H. influenzae DNA fragment involved in the PEP-mediated beta-lactam resistance of strain T-1,3 was used as a probe for specific detection of H. influenzae strains in clinical specimens. (ucalgary.ca)
  • Beta-lactam antibiotic resistance in Streptococcus pneumoniae arises readily as the bacteria can quickly incorporate DNA fragments encompassing variants that make the transformed strains resistant. (cdc.gov)
  • By comparing a large number of genomes of beta-lactam susceptible and non-susceptible strains, the high frequency of recombination should break up these haplotype blocks and allow the use of genetic association approaches to identify individual causative variants. (cdc.gov)
  • perform highly controlled evolution experiments in E. coli strains to identify genetic perturbations that strongly limit the evolution of antibiotic resistance through epistasis. (nature.com)
  • An increase of extended-spectrum beta-lactamase (ESBL) producing strains is a worldwide problem. (bvsalud.org)
  • A large proportion of these strains showed conjugally transferable, plasmid -mediated, beta-lactam resistance . (bvsalud.org)
  • Augmentin, a drug that contains both a beta-lactam (typically amoxicillin) and clavulanic acid (a beta-lactamase inhibitor), is often prescribed to overcome drug resistant strains. (wikibooks.org)
  • and the emergence of extended-spectrum beta-lactamase (ESBL)-producing E. coli strains with the ability to hydrolyze penicillins, cephalosporins and monobactams. (scielosp.org)
  • Production of chromosome-encoded β-lactamases confers resistance to β-lactams in many Gram-negative bacteria. (frontiersin.org)
  • In Gram-negative bacteria, the production of β-lactamases is the predominant strategy of resistance to β-lactams. (frontiersin.org)
  • Growth of such bacteria at pH 5.2 completely suppressed the expression of methicillin resistance. (asm.org)
  • Does broad-spectrum beta-lactam resistance due to NDM-1 herald the end of the antibiotic era for treatment of infections caused by Gram-negative bacteria? (nih.gov)
  • Because of the popularity of beta-lactam drugs, certain bacteria have been able to develop counter-measures to traditional drug therapies. (princeton.edu)
  • An enzyme called beta-lactamase is present in many different types of bacteria, which serves to 'break' the beta lactam ring, which effectively nullifies the antibiotic's effectiveness. (princeton.edu)
  • The BETA-LACTAMASES hydrolyze the beta lactam ring, accounting for BETA-LACTAM RESISTANCE of infective bacteria. (bioportfolio.com)
  • The antibiotic resistance crisis calls for new ways of restricting the ability of bacteria to evolve resistance. (nature.com)
  • β-lactam exhibits its antibiotic properties by imitating the naturally occurring d-Ala-d-Ala substrate for the group of enzymes known as penicillin binding proteins (PBP), which have as function to cross-link the peptidoglycan part of the cell wall of the bacteria. (wikipedia.org)
  • They are still widely used today for different bacterial infections, though many types of bacteria have developed resistance following extensive use. (wikipedia.org)
  • This study was conducted to find out the resistant mechanism in carbapenem-resistant Gram-negative bacteria phenotypically and to detect resistance gene NDM-1 in our hospital setting. (hindawi.com)
  • Some bacteria have developed resistance to beta-lactams. (wikibooks.org)
  • These bacteria contain beta-lactamases, a broad class of enzymes with a serine residue that cleaves the reactive beta lactam ring through an acyl-enzyme intermediate . (wikibooks.org)
  • And in September, a Spanish study found that nearly 10 per cent of people now have beta lactam-resistant gut bacteria, compared with just 0.3 per cent in 1991. (newscientist.com)
  • Drug resistance developed in human pathogenic bacteria is emerging and has become a global problem. (intechopen.com)
  • Beta-lactam resistance in Gram-negative bacteria. (escmid.org)
  • According to a recent EMEA report, resistance among Gram-positive and Gram-negative bacteria is already reaching 25% or more in several EU Member States. (smi-online.co.uk)
  • Those bacteria are believed potential reservoirs of level of resistance because of the 900515-16-4 supplier complicated transmitting routes between farms and customers. (cylch.org)
  • The regular transfer of level of resistance genes among web host bacteria is now more noticeable with molecular research, that have shown the distribution from the same gene in various bacteria of human or animal origin [7]. (cylch.org)
  • In fact, critical public health hazards arise because of the ability of many bacteria to acquire resistance traits to different antimicrobials. (cylch.org)
  • Antibiotic resistance mediated by MDR plasmids severely limits the treatment options for the infections caused by Gram-negative bacteria, especially Enterobacteriaceae family. (wikipedia.org)
  • The resistance conferred by this gene (blaNDM-1), therefore, aids the expansion of bacteria that carry it throughout a human host, since they will face less opposition/competition from populations of antibiotic-sensitive bacteria, which will be diminished by the original antibacterial treatment. (wikipedia.org)
  • Salmonella isolates with reduced susceptibility to beta-lactams ( n = 43) were tested for genes encoding for beta-lactamase enzymes, and those resistant to quinolones ( n = 29) for mutations in the quinolone resistance determining region (QRDR) as well as plasmid mediated quinolone resistance (PMQR) genes using PCR and sequencing. (springer.com)
  • Beta-lactamase genes ( bla ) were detected in 34 (79.1%) of the isolates. (springer.com)
  • Plasmid mediated quinolone resistance (PMQR) genes investigated were not detected in any of the isolates. (springer.com)
  • Indicative of this limited resolution is the frequent use of the term "mosaic genes" to describe pneumococcal resistance alleles [7] . (prolekare.cz)
  • Although recombinational mosaics are clearly identifiable as regions of several hundred nucleotides in resistance genes, it is likely that only a subset of the observed alterations are important in causing resistance. (prolekare.cz)
  • In this study real-time PCR assays, based on the LUX-technique, were developed for quantification of genes mediating resistance to aminoglycosides [aac(6 ')-Ie + aph(2 ' ')], beta-lactams (mecA), and tetracyclines (tetA and tetB), for use in wastewater environments. (diva-portal.org)
  • The developed LUX real-time PCR assays were shown to be fast and reproducible tools for detection and quantification of the four genes encoding antibiotic resistance in wastewater. (diva-portal.org)
  • PSE, PER-1, OXA-10-like beta-lactamase genes and MEX-R genes of isolates were investigated by polymerase chain reaction (PCR). (istanbul.edu.tr)
  • Additionally, it will show you how to use genomic analysis tools to analyze whole genome sequencing data to detect resistance genes (and or other genes of interest) in a simple and easy way using online tools freely available. (coursera.org)
  • Understand the concept and be able to apply genomic analysis tools used to detect resistance genes and other relevant genes from Whole Genome Sequencing (WGS) data (with demonstration of selected online tools) Disclaimer: Please note that the guidelines and methods referred or links included in these materials are updated when the videos lectures are produced and before the course is released, however these might become outdated with time. (coursera.org)
  • However, the causative mutations themselves are embedded within larger recombined blocks, and previous studies have only analysed a limited number of isolates, leading to the description of "mosaic genes" as being responsible for resistance. (cdc.gov)
  • AR is ancient with VanX proto-resistance and multi-resistance genes being detected in ~30,000-year old DNA from permafrost 8 . (nature.com)
  • Several antibiotic resistance genes (ARGs) were quantified using qPCR in three WWTPs of decreasing capacity located in Helsinki, Tallinn, and Tartu, respectively: sulphonamide resistance genes (sul1 and sul2), tetracycline resistance genes (tetM and tetC), and resistance genes for extended spectrum beta-lactams (blaoxa-58, blashv-34, and blactx-m-32). (ku.dk)
  • In all other cases the purification process caused no significant change in the relative abundance of resistance genes, while the raw abundances fell by several orders of magnitude. (ku.dk)
  • Standard water quality variables (biological oxygen demand, total phosphorus and nitrogen, etc.) were weakly related or unrelated to the relative abundance of resistance genes. (ku.dk)
  • Based on our results we conclude that there is neither considerable enrichment nor purification of antibiotic resistance genes in studied conventional WWTPs. (ku.dk)
  • Bacterial resistance occurs as a result of the expression of one of many genes for the production of β-lactamases, a class of enzymes that break open the β-lactam ring. (wikipedia.org)
  • The global transcriptional response of the bacterium to β-lactams was investigated, and changes in levels of expression of cell wall biosynthetic genes were identified. (asm.org)
  • These findings reveal a road map of genes required for β-lactam resistance and validate synthetic lethality screening as a promising tool for repurposing existing classes of licensed, safe, well-characterized antimicrobials against tuberculosis. (asm.org)
  • Our study identifies molecular determinants of innate resistance to β-lactam drugs in M. tuberculosis , and we demonstrate that functional loss of one of these genes enables successful treatment of M. tuberculosis with β-lactams in the mouse model. (asm.org)
  • Also, the horizontal transfer of resistance genes as groups ("cassettes") or plasmids makes the spread of resistance to different bacterial genera possible, among which there could be pathogens. (intechopen.com)
  • Plasmids carrying the bla NDM-1 gene also carry a number of other genes conferring resistance to many more classes of drugs apart from beta-lactam as aminoglycoside, macrolide, and sulfamethoxazole. (hindawi.com)
  • Genes encoding ESBL production are frequently found in plasmids and are usually accompanied by other genes for resistance to cephalosporins, sulfonamides, fluoroquinolones and aminoglycosides ( 3 3. (scielosp.org)
  • this research represents the first ever to survey quantitatively monitor antibiotic level of resistance genes (ARG) in goat and lamb slaughterhouse utilizing a lifestyle independent strategy, since most research focused on person bacterial types and their particular level of resistance types. (cylch.org)
  • the surveillance and control of spread of antibiotic resistance genes (ARG) throughout meals chain provides great relevance since individuals are increasingly alert to problems over antibiotic resistant bacterias in foods, those of animal origin especially. (cylch.org)
  • The main goal of the present study was to quantitatively track the frequency and the distribution of ARG in different slaughterhouse surfaces throughout meat chain production (and in the commercial meat products) by quantitative real-time PCR for tetracycline, beta-lactam and sulfonamide resistance genes. (cylch.org)
  • Plasmid-mediated resistance is the transfer of antibiotic resistance genes which are carried on plasmids. (wikipedia.org)
  • Plasmids often carry multiple antibiotic resistance genes, contributing to the spread of multidrug-resistance (MDR). (wikipedia.org)
  • Resistance plasmids by definition carry one or more antibiotic resistance genes. (wikipedia.org)
  • They are frequently accompanied by the genes encoding virulence determinants, specific enzymes or resistance to toxic heavy metals. (wikipedia.org)
  • Multiple resistance genes are commonly arranged in the resistance cassettes. (wikipedia.org)
  • The antibiotic resistance genes found on the plasmids confer resistance to most of the antibiotic classes used nowadays, for example, beta-lactams, fluoroquinolones and aminoglycosides. (wikipedia.org)
  • It is very common for the resistance genes or entire resistance cassettes to be re-arranged on the same plasmid or be moved to a different plasmid or chromosome by means of recombination systems. (wikipedia.org)
  • Quinolone resistance genes are frequently located on the same plasmid as the ESBL genes. (wikipedia.org)
  • Aminoglycoside resistance genes are also commonly found together with ESBL genes. (wikipedia.org)
  • This particularly broad spectrum of antibiotic resistance was heightened by the strain's expressing several different resistance genes in addition to blaNDM-1. (wikipedia.org)
  • β-Lactam resistance in methicillin-resistant Staphylococcus aureus USA300 is increased by inactivation of the ClpXP protease. (semanticscholar.org)
  • Beta-lactam resistance mechanisms of methicillin-resistant Staphylococcus aureus. (unil.ch)
  • Analysis of beta-lactamase production in ampicillin-resistant Escherichia coli isolated from blood cultures 1983-1989. (springer.com)
  • However, in cases of invasive complicated salmonellosis, treatment with beta-lactam antimicrobials such as ampicillin, ceftriaxone and quinolone drugs are employed as lifesaving agents [ 5 ]. (springer.com)
  • This study has revealed that there exists a high level of resistance to penicillins like ampicillin, methicillin and cloxacillin and the first generation cephalosporin, cephalexin. (ijpsonline.com)
  • The prevalence of clinical PBP3-mediated resistance to ampicillin was 9%, compared to 2.5% three years earlier. (biomedcentral.com)
  • Traditionally, isolates with the latter resistance mechanism have been denoted beta-lactamase negative ampicillin resistant (BLNAR), whereas isolates with both mechanisms have been denoted beta-lactamase positive amoxicillin-clavulanate resistant (BLPACR). (biomedcentral.com)
  • All isolates were susceptible to cefoxitin, beta-lactam/BL inhibitor combinations, and carbapenems, except for Peptostreptococcus isolates (4% were resistant to ampicillin/sulbactam) and Porphyromonas (5% were resistant to cefoxitin) (20). (rrnursingschool.biz)
  • Whereas the substitutions clearly led to in vitro clavulanic acid resistance in enzymatic assays but at the expense of catalytic activity, transformation of variant BlaCs into an M. tuberculosis H37Rv background revealed that impaired inhibition of BlaC did not affect inhibition of growth in the presence of ampicillin and clavulanate. (rcsb.org)
  • Ominously, researchers investigating an upsurge of Group A strep cases in Seattle found a mutated strain that confers resistance to ampicillin and other beta-lactam drugs. (reliasmedia.com)
  • 1 Genomic analysis showed a "first-step mutation" that conferred resistance to ampicillin. (reliasmedia.com)
  • Resistance in studies in countries outside the OECD was significantly higher: 79.8% (73.0% to 87.7%) for ampicillin, 60.3% (40.9% to 79.0%) for co-amoxiclav, 26.8% (11.1% to 43.0%) for ciprofloxacin, and 17.0% (9.8% to 24.2%) for nitrofurantoin. (bmj.com)
  • Previous studies suggested host-specificity of VREF into previously described VREF genogroups, and strong genogroups (11), and isolates associated with nosocomial associations were found between VSEF and VREF isolates with resistance to ampicillin, presence of esp , and purK 1. (cdc.gov)
  • The ampicillin resistance were most frequent among outbreak- differences between epidemic and nonepidemic isolates associated isolates and almost absent among community were based on genetic relatedness, as determined by surveillance isolates. (cdc.gov)
  • The genetic relatedness was were determined by standard agar dilution methods, linked to the presence of the variant esp gene and antibiot- according to the National Committee for Clinical ic resistance to ampicillin and vancomycin. (cdc.gov)
  • An intriguing property of all methicillin-resistant staphylococci is the dependence of resistance on the pH value of the growth medium. (asm.org)
  • Over half of the quinolone resistant isolates in the current study 17 (58.6%) were also resistant to at least one of the beta-lactam antimicrobials. (springer.com)
  • Identification of the specific genetic determinants of beta-lactam resistance is essential to understand both the mechanism of resistance and the spread of resistant variants in the pneumococcal population. (prolekare.cz)
  • These represented the most resistant organisms of 1866 isolates collected during a national survey of antibiotic resistance in this species. (microbiologyresearch.org)
  • In one multicenter study 83% of Prevotella isolates were resistant to penicillin G, whereas resistance was lower for Porphyromonas (21%), Fusobacterium (9%), and Peptostreptococcus (6%) (20). (rrnursingschool.biz)
  • Low dosage and long treatment duration of beta-lactam: risk factors for carriage of penicillin-resistant Streptococcus pneumoniae. (nih.gov)
  • The spread of drug-resistant Streptococcus pneumoniae in the community is a public health problem in developed and developing nations, but whether antibiotic use is responsible for the increase in drug resistance is not known. (nih.gov)
  • To analyze the relationship between penicillin-resistant S pneumoniae (PRSp) pharyngeal carriage and characteristics of beta-lactam use. (nih.gov)
  • Can inhibitor-resistant substitutions in the Mycobacterium tuberculosis beta-Lactamase BlaC lead to clavulanate resistance? (rcsb.org)
  • When bacterial populations have these resistant subgroups, treatment with β-lactam can result in the resistant strain becoming more prevalent and therefore more virulent. (wikipedia.org)
  • Used mainly for treatment of beta lactam resistant bugs, esp. (sporcle.com)
  • The 65.7% (46/70) of the isolates presented a multidrug-resistant phenotype and 55.7% (39/70) were extended-spectrum beta-lactamases producers. (scielosp.org)
  • A recent increase in antibiotic-resistant foodborne outbreaks shows the emergence of resistance [14]. (cylch.org)
  • Low-affinity penicillin-binding protein associated with beta-lactam resistance in Staphylococcus aureus. (asm.org)
  • Methicillin resistance in Staphylococcus aureus has been associated with alterations in the penicillin-binding proteins (PBPs). (asm.org)
  • Contribution of peptidoglycan amidation to beta-lactam and lysozyme resistance in different genetic lineages of Staphylococcus aureus. (semanticscholar.org)
  • Molecular basis and phenotype of methicillin resistance in Staphylococcus aureus and insights into new beta-lactams that meet the challenge. (semanticscholar.org)
  • lactam Resistance in Staphylococcus aureus. (ucsf.edu)
  • The crystal structure of beta-lactamase from Staphylococcus aureus inactivated by p-nitrophenyl[[N-(benzyloxycarbonyl)amino]methyl]phosphonate, a methylphosphonate monoester monoanion inhibitor, has been determined and refined at 2.3 A resolution. (rcsb.org)
  • Antimicrobial resistance by Staphylococcus aureus is a global epidemic. (hrb.ie)
  • Typically, these potentiators are not bactericidal by themselves and function by reversing resistance mechanisms, by attenuating Staphylococcus aureus virulence, and/or by interfering with quorum sensing. (ugent.be)
  • Although the use of cephalosporins is far more extensive in Finland than in other Scandinavian countries, none of the isolates produced extended-spectrum beta-lactamases. (springer.com)
  • In conclusion, resistance to cefuroxime has remained rare in Finland, and cefuroxime is still an alternative to third-generation cephalosporins in the treatment of septicemia. (springer.com)
  • The three beta-lactamases hydrolyzed penicillins and cephalosporins (including cefotaxime and ceftriaxone) and were therefore designated "extended broad-spectrum beta-lactamases" (EBS-Bla). (nih.gov)
  • Rapid detection of resistance to carbapenems and cephalosporins in Enterobacteriaceae using liquid chromatography tandem mass spectrometry. (bioportfolio.com)
  • Those who are allergic to penicillin are most often given cephalosporin C (another β-lactam antibiotic) because there is only 10% crossover in allergy between the penicillins and cephalosporins. (wikipedia.org)
  • Aminoglycoside resistance among blood culture isolates. (springer.com)
  • Evaluation of plasmid-encoded beta-lactamase resistance in Escherichia coli blood culture isolates. (springer.com)
  • Before 1985 at the Pitié-Salpêtrière Hospital in Paris (2,400 beds), resistance to cefotaxime in clinical isolates of Enterobacteriaceae involved only species producing inducible class 1 beta-lactamase. (nih.gov)
  • The transferability of cefotaxime resistance in E. coli K12 was demonstrated for 15 of 16 selected isolates. (nih.gov)
  • However, little is known on the genetic basis of resistance to these drugs in Salmonella isolates from Ethiopia. (springer.com)
  • Double substitutions in gyr A (Ser83-Phe + Asp87-Gly) as well as par C (Thr57-Ser + Ser80-Ile) subunits of the quinolone resistance determining region (QRDR) were detected in all S. Kentucky isolates with high level resistance to both nalidixic acid and ciprofloxacin. (springer.com)
  • A study of the prevalence of antimicrobial resistance among respiratory tract isolates was conducted in a secondary care Government hospital in Tamil Nadu in order to gauge the existing level of antimicrobial resistance. (ijpsonline.com)
  • Here, we performed a genome-wide association study on 3,701 isolates collected from two different locations and identified candidate variants that may explain beta-lactam resistance as well as discriminating potential genetic hitchhiking variants from potential causative variants. (prolekare.cz)
  • Clinically significant isolates of the Enterobacteriaceae were screened for patterns of broad-spectrum resistance to beta-lactams. (semanticscholar.org)
  • The B. fragilis group has the highest prevalence of resistance to beta-lactams as almost all (more than 97%) of B. fragilis group isolates resist penicillin G. In contrast, the cephamycins (e.g., cefoxitin cefotetan) have better activity, although the prevalence of resistance among B. fragilis group has increased. (rrnursingschool.biz)
  • PER-1 and OXA-10 like beta-lactamases were detected each in 11% of the isolates, and co-presence of PER-like and OXA-10 like enzymes were shown in 4% of the isolates. (istanbul.edu.tr)
  • Here, we performed a genome-wide association study to identify single nucleotide polymorphisms (SNPs) and indels that could confer beta-lactam non-susceptibility using 3,085 Thai and 616 USA pneumococcal isolates as independent datasets for the variant discovery. (cdc.gov)
  • These isolates had a point mutation predictive of resistance. (reliasmedia.com)
  • A recently dence exists for nosocomial selection of a subtype of E. developed multilocus sequence typing scheme for E. faeci- faecium , which has acquired vancomycin-resistance um confirmed that epidemic isolates belonged to a specif- through horizontal transfer. (cdc.gov)
  • Rates of new cases of colistin resistance by year for K. pneumoniae and all Gram-negative rods, excluding isolates with intrinsic colistin resistance. (asm.org)
  • It has been reported that at least 25% of the foodborne isolates show drug resistance to one or more classes of antimicrobials (FAO 2018). (intechopen.com)
  • Carbapenem resistance among Gram-negative isolates caused by the production of the metallo- β -lactamase (MBL) enzyme is being increasingly reported worldwide. (hindawi.com)
  • We characterized the antimicrobial resistance of 70 Escherichia coli isolates obtained from patients with a urinary tract infection (UTI) from 8 public hospitals in Peru. (scielosp.org)
  • These results show high resistance levels to antimicrobials of clinical use in E. coli isolates from hospital UTI patients in Peru. (scielosp.org)
  • As of June 2010[update], there were three reported cases of Enterobacteriaceae isolates bearing this newly described resistance mechanism in the US, the Centers for Disease Control and Prevention (CDC) stated that "All three U.S. isolates were from patients having received recent medical care in India. (wikipedia.org)
  • In this study, we investigated impacts of such enzymes on susceptibility to β-lactams. (frontiersin.org)
  • These enzymes, which resemble PBPs structurally and mechanistically, have ability to rapidly hydrolyze the β-lactams ( Nicholas and Davies, 2012 ). (frontiersin.org)
  • The enzymes conferred to derivatives a high level of resistance to amoxicillin, ticarcillin, piperacillin, and cephalothin and a decreased degree of susceptibility (i.e. (nih.gov)
  • The common mechanism of resistance to beta-lactam antimicrobials is due to production of beta-lactamase enzymes with variable level of activity against different generations of beta-lactam antimicrobials. (springer.com)
  • The clavulanic acid is designed to overwhelm all beta-lactamase enzymes, bind irreversibly to them, and effectively serve as an antagonist so that the amoxicillin is not affected by the beta-lactamase enzymes. (princeton.edu)
  • A shared mechanistic feature of the marketed β-lactam-based inhibitors is their reaction with the serine enzymes to form a covalent acyl-enzyme intermediate. (pnas.org)
  • Originally designed to combat class A serine β-lactamase enzymes such as TEM-1, the clinical use of β-lactam-based inhibitors has been diminished by the emergence of enzymes against which they are ineffective. (pnas.org)
  • Certain molecules called BETA-LACTAM INHIBITORS , however, can bind to beta-lactamase enzymes and inactivate them. (thefreedictionary.com)
  • Beta-lactamases are enzymes that cleave the beta-lactam ring , opening up the structure and destroying the ability of the beta-lactam to bind to its target. (thefreedictionary.com)
  • New enzymes evolve over time by mutation in the existing resistance enzyme in response to environmental pressure. (hindawi.com)
  • Metallo- β -lactamases are enzymes that break down beta-lactam drugs. (hindawi.com)
  • The first clinically observed ESBL enzymes were mutated versions of the narrow spectrum beta-lactamases, like TEM and SHV. (wikipedia.org)
  • Resistance to aminoglycosides is conferred via numerous aminoglycoside-modifying enzymes and 16S rRNA methyltransferases. (wikipedia.org)
  • The gene for NDM-1 is one member of a large gene family that encodes beta-lactamase enzymes called carbapenemases. (wikipedia.org)
  • The carbapenems were developed to overcome antibiotic resistance mediated by bacterial beta-lactamase enzymes. (wikipedia.org)
  • One set of studies compared a broad-spectrum beta lactam versus a different, generally narrower-spectrum beta lactam combined with an aminoglycoside (47 studies). (cochrane.org)
  • The other studies compared one beta lactam versus the same beta lactam combined with an aminoglycoside antibiotic (22 studies). (cochrane.org)
  • The review authors concluded that beta lactam-aminoglycoside combination therapy does not provide an advantage over beta lactams alone. (cochrane.org)
  • The addition of an aminoglycoside to beta lactams for sepsis should be discouraged. (cochrane.org)
  • Combining a beta lactam antibiotic with an aminoglycoside antibiotic may provide certain advantages over beta lactam monotherapy. (cochrane.org)
  • We included randomized and quasi- randomized trials comparing any beta lactam monotherapy versus any combination of a beta lactam with an aminoglycoside for sepsis. (cochrane.org)
  • Thus, when several mechanisms of resistance to beta-lactam agents are present in the same strain of Pseudomonas aeruginosa, there is no additive effect between these mechanisms. (nih.gov)
  • Jeannat, K. and Plesiat, P. (2005) Therapeutic Implication of Antibiotic Resistance in Pseudomonas. (scirp.org)
  • Lecture 1: Multidrug resistance in Acinetobacter, Pseudomonas and Stenotrophomonas. (escmid.org)
  • Understanding the determinants of resistance at the single nucleotide level will be important for the future use of sequence data to predict resistance in the clinical setting. (prolekare.cz)
  • This analysis does not include mutations that may result in antibiotic resistance or resistance determinants added to newer versions of the ResFinder database or other antimicrobial resistance gene databases. (cdc.gov)
  • To identify the genetic determinants of innate β-lactam resistance, we carried out a synthetic lethality screen on a transposon mutant library for susceptibility to imipenem, a carbapenem β-lactam antibiotic. (asm.org)
  • Penams have values in the range 0.40-0.50 Å, while carbapenems and clavams have values of 0.50-0.60 Å, being the most reactive of the β-lactams toward hydrolysis. (wikipedia.org)
  • Yet there is significant concern that drug resistance against this combination will also emerge. (rcsb.org)
  • BACKGROUND: Transmitted HIV drug resistance can threaten the efficacy of antiretroviral therapy (ART) and preexposure prophylaxis (PrEP). (cdc.gov)
  • Drug resistance testing is recommended at entry to HIV care in the United States and provides valuable insight for clinical decision-making and population-level monitoring. (cdc.gov)
  • METHODS: We assessed transmitted drug resistance-associated mutation (TDRM) prevalence and predicted susceptibility to common HIV drugs among U.S. persons with HIV diagnosed during 2014-2018 who had a drug resistance test performed ≤3 months after HIV diagnosis and reported to the National HIV Surveillance System and who resided in 28 jurisdictions where ≥20% of HIV diagnoses had an eligible sequence during this period. (cdc.gov)
  • The drug abuse known to occur during growth of animals intended for food production, because of their use as either a prophylactic or therapeutic treatment, promotes the emergence of bacterial drug resistance. (intechopen.com)
  • There are diverse mechanisms that promote drug resistance. (intechopen.com)
  • Subcloning of individual fragments derived from one recombinant cosmid (pLB100) indicated that two adjacent fragments of DNA were both capable of transforming the susceptible strain Rd to betalactam resistance and altered PBP expression. (ucalgary.ca)
  • Antibiosis resistance affects the biology of the insect so pest abundance and subsequent damage is reduced compared to that which would have occurred if the insect was on a susceptible crop variety. (wikipedia.org)
  • Penicillin-binding protein (PBP) 5 of Streptococcus faecium has been shown to have a very low affinity for penicillin, and this PBP was suggested to be responsible for both the natural low susceptibility and high resistance to the antibiotic in this species (R. Fontana, R. Cerini, P. Longoni, A. Grossato, and P. Canepari, J. Bacteriol. (asm.org)
  • Our results suggest the potential for emergence of clinically significant beta-lactam resistance in Group A streptococcus," Kirsten Vannice , PhD, MHS, said recently in Atlanta at the CDC Epidemic Intelligence Service (EIS) conference. (reliasmedia.com)
  • NDM-1 functions through two zinc ions present in the active site that cause hydrolysis of the beta-lactams, rendering them ineffective. (wikipedia.org)
  • Extended broad-spectrum beta-lactamases conferring transferable resistance to newer beta-lactam agents in Enterobacteriaceae: hospital prevalence a. (nih.gov)
  • Prevalence and mechanisms of broad-spectrum beta-lactam resistance in Enterobacteriaceae: a children's hospital experience. (semanticscholar.org)
  • article{Qin2008PrevalenceAM, title={Prevalence and mechanisms of broad-spectrum beta-lactam resistance in Enterobacteriaceae: a children's hospital experience. (semanticscholar.org)
  • The mechanism of resistance to broad-spectrum beta-lactams in P.aeruginosa are overexpression of cephalosporinases and/or class A, B and D beta-lactamases. (istanbul.edu.tr)
  • 2 Screen for metallo-beta-lactamase production [Rasheed et al. (cdc.gov)
  • This high prevalence of resistance resulted in recent recommendations against the use of both cephamycins as empirical therapy for intra-abdominal infections (42). (rrnursingschool.biz)
  • Guidelines recommend three options for first-line treatment of acute uncomplicated cystitis: fosfomycin, nitrofurantoin, and trimethoprim/sulfamethoxazole (in regions where the prevalence of Escherichia coli resistance does not exceed 20 percent). (aafp.org)
  • Beta-lactam and quinolone antimicrobials are commonly used for treatment of infections caused by non-typhoidal Salmonella (NTS) and other pathogens. (springer.com)
  • Beta-lactams are still useful agents for the treatment of anaerobic infections, even though significant resistance has been noted. (rrnursingschool.biz)
  • This 3 arm study will compare the efficacy and safety of beta-lactam with that of 'standard care' in patients with complicated skin and skin structure infections requiring hospitalization. (bioportfolio.com)
  • Avibactam is a β-lactamase inhibitor that is in clinical development, combined with β-lactam partners, for the treatment of bacterial infections comprising Gram-negative organisms. (pnas.org)
  • A mainstay for treatment of Gram-negative infections is the β-lactam classes of drugs. (pnas.org)
  • Both patients had received multiple courses of beta-lactams in the preceding three years due to recurrent strep infections. (reliasmedia.com)
  • There have been few studies about the kinds of species causing surgical site infections and their resistance pattern in Korea . (bvsalud.org)
  • Members of Enterobacteriaceae family, for example, Escherichia coli or Klebsiella pneumoniae pose the biggest threat regarding plasmid-mediated resistance in hospital- and community-acquired infections. (wikipedia.org)
  • Clinical variables associated with the isolation of Klebsiella pneumoniae expressing different extended-spectrum beta-lactamases. (semanticscholar.org)
  • Understand the basic concepts of antimicrobial resistance from several perspectives (clinical, research and microbiological) 3. (coursera.org)
  • The molecular basis of clinical penicillin-binding protein-modulated beta-lactam resistance of the Haemophilus influenzae strain T-1,3 was studied. (ucalgary.ca)
  • As new β-lactams have been introduced into clinical use, a changing landscape of β-lactamases has been selected and disseminated. (pnas.org)
  • The three inhibitors approved for clinical use are clavulanic acid, tazobactam, and sulbactam, all of which contain a β-lactam core. (pnas.org)
  • The use of beta-lactam allergy skin testing (BLAST) at the point of care in hospital antimicrobial stewardship programs (ASPs) resulted in greater use of preferred beta-lactam therapy without increasing the risk of adverse drug reactions, according to a study yesterday in Clinical Infectious Diseases . (umn.edu)
  • Impact of extended-spectrum beta-lactamase-producing Escherichia coli and Klebsiella species on clinical outcomes and hospital costs: a matched cohort study. (scielosp.org)
  • Examples of resistance mechanisms include different Qnr proteins, aminoglycose acetyltransferase aac(6')-Ib-cr that is able to hydrolyze ciprofloxacin and norfloxacin, as well as efflux transporters OqxAB and QepA. (wikipedia.org)
  • Relate the phenotypical results with results from genotyping using molecular techniques for detection of resistance mechanisms 12. (coursera.org)
  • Studies on the molecular basis of penicillin-binding protein-mediated beta-lactam resistance in haemophilus influenza (Unpublished doctoral thesis). (ucalgary.ca)
  • Apart from performing only antimicrobial sensitivity test, phenotypic and molecular screening should be employed to find out the actual number of metallo- β -lactamase producers and the existence of the resistance gene. (hindawi.com)
  • Phenotypic and molecular detection of CTX-M-beta-lactamases produced by Escherichia coli and Klebsiella spp. (scielosp.org)
  • Acquisition of bla TEM was the principal beta-lactamase resistance mechanism and mutations within QRDR of gyr A and par C were the primary mechanism for resistance to quinolones. (springer.com)
  • Beta-lactam resistance in Haemophilus influenzae due to ftsI mutations causing altered penicillin-binding protein 3 (PBP3) is increasing worldwide. (biomedcentral.com)
  • Impact of mecA promoter mutations on mecA expression and beta-lactam resistance levels. (semanticscholar.org)
  • lactam Resistance to identify mutations of importance. (ucsf.edu)
  • thus, mutations that increase beta-lactamase activity likely increase also susceptibility to the inhibitor. (nature.com)
  • identify rare mutations in the ampC beta-lactamase gene that escape this adaptive tradeoff specifically for certain drug combinations. (nature.com)
  • The objective of this study was to investigate the trends and patterns of resistance in beta-lactamase-producing members of the family Enterobacteriaceae in a children's hospital over a 9-year period (1999 to 2007). (semanticscholar.org)
  • Extended-spectrum beta-lactamase-type SHV-12-producing Enterobacteriaceae causing septicemia in Tanzanian children: vectors for horizontal transfer of antimicrobial resistance. (semanticscholar.org)
  • Lecture 11: Current trends in resistance to beta-lactams and fluoroquinolones in Enterobacteriaceae. (escmid.org)
  • Both narrow spectrum beta-lactamases (e.g. penicillinases) and extended spectrum beta-lactamases (ESBL) are common for resistance plasmids in Enterobacteriaceae. (wikipedia.org)
  • The NDM-1 gene, first identified in Sweden in 2008 in Klebsiella pneumoniae from a patient hospitalized in New Delhi, encodes a metallo-β-lactamase that inactivates all β-lactams except aztreonam. (nih.gov)
  • To understand how PEP-mediated beta-lactam resistance developed in H. influenzae, the cloning of the altered PBP expression gene f ram strain T-1, 3 was undertaken. (ucalgary.ca)
  • This mutation was located within the pbp2x gene at the same site that is known to reduce beta-lactam susceptibility in other strep species, including S. pneumoniae ," she said. (reliasmedia.com)
  • Resistance gene patterns suggest they were disseminated throughout slaughterhouse zones being also recognized in commercial meat products, with significant correlations between different sampling zones/end products and total resistance in SR, CR and white space (WR) zones, and also refrigerator 4 (F4) and MP were observed. (cylch.org)
  • Resistance to these classes of antimicrobials has increased significantly in the recent years. (springer.com)
  • The course will cover the topics related to antimicrobial resistance with basic definitions and overview on antimicrobials their use and the emergence and spread of resistance. (coursera.org)
  • Empiric management of a patient presenting with signs and symptoms of acute rhinosinusitis is discussed below, with a focus on supportive therapy, indications for and choice of antimicrobials, and special circumstances related to the pediatric patient, penicillin-allergic patient, risk for antibiotic resistance, failure of initial therapy, and severe illness. (medscape.com)
  • The pheno-genotypic profiles of beta-lactam resistance were also investigated, this characterization is important, considering that the use of antimicrobials is a key element for mastitis control in dairy farms . (bvsalud.org)
  • Although antimicrobial resistance (AMR) is a natural phenomenon, the process has been much enhanced because of the overuse, underuse, and misuse of antimicrobials both in humans and animals ( 10 - 13 ). (frontiersin.org)
  • The emergence and evolution of S. pneumoniae resistance are subjects of great concern. (elsevier.es)
  • and because only PBP 3a showed an altered electrophoretic mobility when eel ls were grown at 42°C. However, these three PBPs were related to each other because they were the preferred targets for three different beta-lactams in a competitive penicillin-binding assay. (ucalgary.ca)
  • Twenty-two trials compared the same beta lactam in both study arms, while the remaining trials compared different beta lactams using a broader-spectrum beta lactam in the monotherapy arm. (cochrane.org)
  • Here, the authors elucidate the dynamics of developing resistance to ALK inhibitors in an ALK+ lung cancer cell line showing that resistance originates from drug-specific tolerant cancer cells and it develops as a gradual adaptation. (nature.com)
  • A second quantitative real-time PCR (qPCR)-based synthetic lethality screen of randomly selected mutants confirmed the role of cell wall biosynthesis in β-lactam resistance. (asm.org)
  • Notably, all increased β-lactam resistance phenotypes were in accordance with enhanced blaA expression. (frontiersin.org)
  • This study will assess the efficacy and safety of intravenous beta-lactam, in comparison with ceftriaxone, in hospitalized patients with community-acquired pneumonia not caused by Legionel. (bioportfolio.com)
  • [ 1 ] A lactam is a cyclic amide . (princeton.edu)
  • A lactam is a cyclic amide, and beta-lactams are named so because the nitrogen atom is attached to the β-carbon atom relative to the carbonyl. (wikipedia.org)
  • a biochemical rationale for the use of beta-lactam-beta-lactamase inhibitor combinations. (rcsb.org)
  • From these data we propose that resistance to β-lactam-β-lactamase inhibitor combinations will likely not arise from structural alteration of BlaC, therefore establishing confidence that this therapeutic modality can be part of a successful treatment regimen against M. tuberculosis. (rcsb.org)
  • The aim of this study was to investigate beta-lactam resistance in Escherichia coli and Klebsiella spp. (springer.com)
  • The old axiom of "use it and lose it" speaks to the historical trend of antibiotic use eventually selecting out bacterial resistance that renders the drug ineffective. (reliasmedia.com)
  • By isoelectric focusing using iodometric detection with 20 mg of ceftriaxone/100 mL and determination of substrate and inhibition profiles, three beta-lactamases mediating cefotaxime resistance were identified as SHV-2 (isoelectric point [pI] 7.6), CTX-1 (pI 6.3), and "SHV-2-type" or SHV-3 (pI 6.98). (nih.gov)
  • 12. The method of claim 10, wherein the beta-lactam compound is ceftriaxone sodium. (freepatentsonline.com)
  • 13. The method of claim 11, wherein the beta-lactam compound is ceftriaxone disodium salt, sesquaterhydrate. (freepatentsonline.com)
  • Little is known about beta-lactam doses necessary for this infection for patients treated with continuous veino-veinous hemodialysis. (bioportfolio.com)
  • Eligibility criteria for selecting studies Studies were eligible if they investigated and reported resistance in community acquired urinary tract infection in children and young people aged 0-17. (bmj.com)
  • As a response to bacterial resistance to beta-lactam drugs, there are drugs, such as Augmentin / CLA , that are designed to disable the beta-lactamase enzyme. (princeton.edu)
  • Resistance even to these groups of drugs has made treatment difficult. (hindawi.com)
  • Changes in microbiome diversity following beta-lactam antibiotic treatment are associated with therapeutic versus subtherapeutic antibiotic exposure in cystic fibrosis. (bioportfolio.com)
  • No clear difference in all-cause deaths was observed, but treatment failures were fewer with single beta lactam antibiotic treatment. (cochrane.org)
  • Deletion of ampG (encoding permease AmpG) and mrcA (encoding penicillin binding protein 1a, PBP1a) from both double LT mutants further increased the resistance to β-lactams. (frontiersin.org)
  • These beta-lactamases did not affect the activity of cephamycins (cefoxitin, cefotetan, moxalactam) or imipenem. (nih.gov)
  • Resistance to imipenem , cephalotin and amoxicillin + clavulanate was not observed. (bvsalud.org)
  • The purpose of this study is to determine whether a monotherapy with a Beta-Lactam is not inferior to an association of a Beta-Lactam and a macrolide in treating adult patients with commun. (bioportfolio.com)
  • Further study on extended spectrum beta-lactamase and quinolone resistance mechanisms in other gram negative pathogens is recommended. (springer.com)
  • Special attention was given to extended-spectrum beta-lactamases. (springer.com)
  • Outbreak of ceftazidime resistance caused by extended-spectrum β-lactamases at a Massachusetts chronic-care facility. (springer.com)
  • Novel plasmid-mediated extended spectrum beta-lactamases. (springer.com)
  • The continuous increase in the bacterial resistance rate and the slow arrival of new therapeutic options have turned into an antibiotic crisis. (clinicaltrials.gov)
  • The first synthetic β-lactam was prepared by Hermann Staudinger in 1907 by reaction of the Schiff base of aniline and benzaldehyde with diphenylketene in a [2+2] cycloaddition (Ph indicates a phenyl functional group): Up to 1970, most β-lactam research was concerned with the penicillin and cephalosporin groups, but since then, a wide variety of structures have been described. (wikipedia.org)
  • 10. The method of claim 1, wherein the beta-lactam compound is a cephalosporin. (freepatentsonline.com)
  • Extraintestinal Pathogenic Escherichia coli: A Combination of Virulence with Antibiotic Resistance. (scielosp.org)