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)

Example sentence: "After completing her antibiotic course for pneumonia, Mary experienced a superinfection with a fungal infection that required hospitalization."

1. Innate immunity: This is the body's first line of defense against infection, and it involves the recognition and elimination of pathogens by cells and proteins that are present from birth.
2. Acquired immunity: This type of immunity develops over time as a result of exposure to pathogens, and it involves the production of antibodies and other immune cells that can recognize and eliminate specific pathogens.
3. Cell-mediated immunity: This is a type of immunity that involves the activation of immune cells, such as T cells and macrophages, to fight off infection.
4. Genetic resistance: Some individuals may have a genetic predisposition to disease resistance, which can be influenced by their ancestry or genetic makeup.
5. Environmental factors: Exposure to certain environmental factors, such as sunlight, clean water, and good nutrition, can also contribute to disease resistance.

Disease resistance is an important concept in the medical field, as it helps to protect against infectious diseases and can reduce the risk of illness and death. Understanding how disease resistance works can help healthcare professionals develop effective strategies for preventing and treating infections, and it can also inform public health policies and interventions aimed at reducing the burden of infectious diseases on individuals and communities.

To overcome this resistance, β-lactam antibiotics can be given with β-lactamase inhibitors such as clavulanic acid. β-lactam ... β-lactam antibiotics (beta-lactam antibiotics) are antibiotics that contain a beta-lactam ring in their chemical structure. ... List of β-lactam antibiotics ATC code J01C Beta-lactam antibacterials, penicillins ATC code J01D Other beta-lactam ... β-lactams are classified according to their core ring structures. β-lactams fused to saturated five-membered rings: β-lactams ...
β-lactam derived antibiotics can be considered one of the most important antibiotic classes but prone to clinical resistance. β ... A beta-lactam (β-lactam) ring is a four-membered lactam. A lactam is a cyclic amide, and beta-lactams are named so because the ... The Breckpot β-lactam synthesis produces substituted β-lactams by the cyclization of beta amino acid esters by use of a ... Synthesis of β-lactams (Articles with short description, Short description matches Wikidata, Beta-lactams, Four-membered rings) ...
Because of the unfused beta-lactam ring there is somewhat lower cross-reactivity between aztreonam and many other beta-lactam ... and Streptococcus pyogenes have developed resistance to aztreonam to varying degrees. Aztreonam can be safely used in patients ... There is a much lower risk of cross-sensitivity between aztreonam and other beta-lactam antibiotics than within other beta- ... James CW, Gurk-Turner C (January 2001). "Cross-reactivity of beta-lactam antibiotics". Proceedings. 14 (1): 106-107. doi: ...
... 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 ...
Zapun A, Contreras-Martel C, Vernet T (March 2008). "Penicillin-binding proteins and beta-lactam resistance". FEMS Microbiology ... Rice LB (February 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, ...
"Beta-lactam antibiotics: from antibiosis to resistance and bacteriology: BETA-LACTAM RESISTANCE". APMIS. 118 (1): 1-36. doi: ... Kong, Kok-Fai; Schneper, Lisa; Mathee, Kalai (2010). "Beta-lactam antibiotics: from antibiosis to resistance and bacteriology ... A portion of Mathee's research is on β-lactam resistance, particularly the amp pathway where she showed the presence of a β- ... research has been the pathobiology of Pseudomonas aeruginosa chronic infections with specific emphasis on β-lactam resistance, ...
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 ...
Kong KF, Schneper L, Mathee K (January 2010). "Beta-lactam antibiotics: from antibiosis to resistance and bacteriology". APMIS ... 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." During a study ...
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 (February 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): ...
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 enzyme will bind to the beta-lactam ring which is a structural characteristic for beta-lactams and hydrolyze the ring. ... This mechanism falls under the first general resistance mechanism to beta-lactams. mtr encodes for the protein MtrD which is ... This mechanism falls under the first general mechanism for beta-lactam resistance. The penB gene encodes the porins for N. ... by the plasmid borne TEM-1 type beta-lactamase which falls under the third general mechanism for beta-lactam resistance. There ...
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 ... Antimicrobial resistance, Beta-lactam antibiotics, University of North Carolina at Chapel Hill faculty, University of Delaware ...
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 ... "Entrez Gene: Lactamase, beta 2". Retrieved 2015-07-07. Dominski Z (2007-03-01). "Nucleases of the metallo-beta-lactamase family ... Lactamase, beta 2 is a protein that in humans is encoded by the LACTB2 gene. LACTB2 is located on the 8th chromosome, with its ... The metallo beta-lactamases were first identified in bacteria; ...
In bacterial resistance to beta-lactam antibiotics, the bacteria have beta-lactamase which degrade the beta-lactam rings, ... non beta-lactam beta-lactamase inhibitor), and instead binds reversibly. Ambler Class B beta-lactamases cleave beta-lactams by ... as beta-lactamase production is an important contributor to beta-lactam resistance in these pathogens. In contrast, most beta- ... Beta-lactamases are a family of enzymes involved in bacterial resistance to beta-lactam antibiotics. ...
They are a class of Beta lactam antibiotics used to treat infections caused by bacteria. Penicillin resistance in ... M.I. Page (6 December 2012). The Chemistry of β-Lactams. Springer Science & Business Media. p. 103. ISBN 978-94-011-2928-2. ... and the mechanism of resistance was the production of β-lactamase. Modification of the penicillin molecule so that it was ...
Since the discovery of the beta-lactam antibiotic penicillin, the rates of antimicrobial resistance have increased. Over time, ... Specific patterns of drug resistance or multidrug 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 ...
It is proposed that the MexB systems demonstrates substrate specificity for beta-lactams; while the MexD-system expresses ... Cd2+ and Zn2+ resistance) in Pseudomonas aeruginosa, and Czn (Cd2+, Zn2+, and Ni2+ resistance) in Helicobacter pylori. It has ... "Overexpression of resistance-nodulation-cell division pump AdeFGH confers multidrug resistance in Acinetobacter baumannii". ... Heavy metal resistance by the RND family was first discovered in R. metallidurans through the CzcA and later the CnrA protein. ...
... s, (β-lactamases) are enzymes (EC produced by bacteria that provide multi-resistance to beta-lactam ... "Ambler class A beta-lactamases: TEM". Beta-Lactamase DataBase (BLDB. "Ambler class A beta-lactamases: SHV". Beta-Lactamase ... thereby showing clinical resistance to the beta-lactam-beta lactamase inhibitor combinations of amoxicillin-clavulanate (Co- ... a four-atom ring known as a beta-lactam (β-lactam) ring. Through hydrolysis, the enzyme lactamase breaks the β-lactam ring open ...
Resistance of Streptococcus pneumoniae to penicillin and other beta-lactams is increasing worldwide. It was identified as one ... or antimicrobial resistance). NDM-1 is an enzyme that makes bacteria resistant to a broad range of beta-lactam antibiotics.[ ... 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 ...
... shielding more potent beta-lactams such as ampicillin. Sulbactam itself contains a beta-lactam ring, and has weak antibacterial ... "Molecular Mechanisms of Sulbactam Antibacterial Activity and Resistance Determinants in Acinetobacter baumannii". Antimicrobial ... Singh GS (January 2004). "Beta-lactams in the new millennium. Part-II: cephems, oxacephems, penams and sulbactam". Mini Rev Med ... Beta-lactamase inhibitors, Lactams, Sulfones, Carboxylic acids, All stub articles, Antibiotic stubs). ...
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 bacteria 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. ...
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 ...
... 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. ...
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 ...
Beta-lactam antibiotics, EC 3.5.2, Antimicrobial resistance). ... Carbapenems are a class of beta-lactam antibiotics that are ... NDM-1 is an enzyme that makes bacteria resistant to a broad range of beta-lactam antibiotics. These include the antibiotics of ... NDM-1 functions through two zinc ions present in the active site that cause hydrolysis of the beta-lactams, rendering them ... The carbapenems were developed to overcome antibiotic resistance mediated by bacterial beta-lactamase enzymes. However, the ...
Antibiotics are classified generally as beta-lactams, macrolides, quinolones, tetracyclines or aminoglycosides. Their ... The resistance problem demands that a renewed effort be made to seek antibacterial agents effective against pathogenic bacteria ... In parallel, there has been an alarming increase in antimicrobial resistance of bacteria, fungi, parasites and some viruses to ... Antimicrobial pesticides have the potential to be a major factor in drug resistance. Organizations such as the World Health ...
If the person is allergic to the family of antibiotics which both penicillin and amoxicillin are a part of (beta-lactam ... Previously, observed resistance rates had been 10-30%; the increase is likely the result of overuse of macrolide antibiotics in ... but retaining drug-sensitivity to beta-lactam antibiotics such as penicillin, emerged in Hong Kong in 2011, accounting for at ... There have been signs of antibiotic resistance, and there have been recent outbreaks in Hong Kong in 2011 and in the UK in 2014 ...
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 ...
... to most antibiotics including metronidazole and penicillin as well as resistance to clindamycin and possibly beta-lactams. ...
... species are susceptible to beta-lactam antibiotics. They are isolated with high frequency from all specimen ... Peptostreptococcus are slow-growing bacteria with increasing resistance to antimicrobial drugs. Peptostreptococcus is a normal ...
... or other beta-lactam-allergic people, caution should be exercised because cross sensitivity among beta-lactam antibacterial ... While cephalosporinases (a type of beta-lactamase that inactivates cephalosporins) confers resistance to other cephalosporins, ... Exercise caution in people with known hypersensitivity to beta-lactam antibiotics including ceftaroline. Before therapy with ... reactions and serious skin reactions have been reported with beta-lactam antibiotics, including ceftaroline. ...
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, ... activity and resistance". Antimicrob. Agents Chemother. 43 (4): 727-37. doi:10.1128/AAC.43.4.727. PMC 89199. PMID 10103173. ME ...
New Delhi metallo-beta-lactamase 1 Common multidrug-resistant organisms (MDROs) India portal Biology portal Medicine portal New ... "Emergence of plasmid-mediated colistin resistance mechanism MCR-1 in animals and human beings in China: A microbiological and ... "Biochemical Characterization of CTX-M-15 from Enterobacter cloacae and Designing a Novel Non-β-Lactam-β-Lactamase Inhibitor". ... a variant of New Delhi metallo-beta-lactamase 1 (NDM-1). He is an elected fellow of the Royal Society of Chemistry, the Biotech ...
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 ...
... a multiple drug resistance to beta-lactam antibiotics. Beta-lactam (β-lactam) antibiotics are a broad-spectrum group that ... As a consequence of the inability of PBP2a to interact with β-lactam moieties, acquisition of mecA confers resistance to all β- ... In Taiwan, ST59 strains, some of which are resistant to many non-beta-lactam antibiotics, have arisen as common causes of skin ... The use of concurrent treatment with vancomycin or other beta-lactam agents may have a synergistic effect.: 637 Both CA-MRSA ...
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- ...
CMY-2 AmpC beta-lactamase and TEM-1 beta-lactamase. Neither of these have resistance to beta-lactam and they do not pass on any ... The resistance that is gained by CMY-2 and TEM-1 is to Gram-negative bacteria. Unevolved CMY-2 demonstrates more resistance ... In vitro evolution shows that there is potential for resistance evolution in relation to cefepime for both CMY-2 and TEM-1. ... Barlow, Miriam; Hall, Barry G (2003). "Experimental Prediction of the Evolution of Cefepime Resistance From the CMY-2 AmpC β- ...
For treatment of infections caused by Gram-positive microorganisms in patients with serious allergies to beta-lactam ... One mechanism of resistance to vancomycin involves the alteration to the terminal amino acid residues of the NAM/NAG-peptide ... Three main resistance variants have been characterised to date among resistant Enterococcus faecium and E. faecalis populations ... Vancomycin resistance evolved in more common pathogenic organisms during the 1990s and 2000s, including vancomycin-intermediate ...
Expression of PBPA2 confers resistance to all β-lactams. These susceptibility data are given on a few medically significant ... 1000 μg/ml Streptococcus pneumoniae 0.39 μg/ml Like other beta-lactam antibiotics, methicillin acts by inhibiting the synthesis ... Methicillin is no longer effective against these organisms due to resistance. Resistance to methicillin is conferred by ... PBP2a works in a similar manner to other PBPs, but it binds β-lactams with very low affinity, meaning they do not compete ...
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 ... Those who are allergic to other β-lactam antibiotics are more likely to be allergic to meropenem as well. Use in pregnancy ... Meropenem, sold under the brand name Merrem among others, is an intravenous β-lactam antibiotic used to treat a variety of ...
... 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 ...
... beta-lactam-betalactamase inhibitor combinations (e.g. piperacillin-tazobactam), Folate antagonists, quinolones, and ... The outer membrane provides these bacteria with resistance to lysozyme and penicillin. The periplasmic space (space between the ... known as beta-lactamases) in the peri-plasmic space. Other classes of drugs that have gram negative spectrum include ... these drugs may be combined with beta-lactamase inhibitors to combat the presence of enzymes that can digest these drugs ( ...
... or a beta-lactam antibiotic). Three classes of vancomycin-resistant S. aureus have emerged that differ in vancomycin ... High-level vancomycin resistance in S. aureus has been rarely reported. In vitro and in vivo experiments reported in 1992 ... is a strain of Staphylococcus aureus that gives resistance to vancomycin at a frequency of 10−6 colonies or even higher. Drug ... The isolate contained the mecA gene for methicillin resistance. Vancomycin MICs of the VRSA isolate were consistent with the ...
Frequent infusions of beta-lactam antibiotics without exceeding total daily dose would help to keep the antibiotics level above ... During critical illness, a state of adrenal insufficiency and tissue resistance to corticosteroids may occur. This has been ... Giving beta-lactam antibiotics continuously may be better than giving them intermittently. Access to therapeutic drug ... In severe sepsis and septic shock, broad-spectrum antibiotics (usually two, a β-lactam antibiotic with broad coverage, or broad ...
Methicillin-resistant Staphylococcus aureus (MRSA) is a dangerous bacteria strain because it is resistant to beta-lactam ... corrosion/oxidation resistance, and fabrication properties. Copper's antibacterial effect was found to be intrinsic in all of ... "Occurrence of Resistance to Antibiotics, Metals, and Plasmids in Clinical Strains of Staphylococcus spp". Archives of Medical ...
... an example being the beta-lactamase gene, which confers resistance to the penicillin group of beta-lactam antibiotics like ... Some vectors contain two selectable markers, for example the plasmid pACYC177 has both ampicillin and kanamycin resistance gene ... 5-bromo-4-chloro-3-indolyl-beta-d-galactoside) into an insoluble, blue product (5,5'-dibromo-4,4'-dichloro indigo). Cloning a ... although some selectable markers such as resistance to zeocin and hygromycin B are effective in different cell types. ...
Resistance to beta-lactam antibiotics has become a particular problem in recent decades, as strains of bacteria that produce ... In 2009, a gene called New Delhi metallo-beta-lactamase (shortened NDM-1) that even gives resistance to intravenous antibiotic ... Antibiotic resistance is a growing problem. Some of this is due to overuse of antibiotics in humans, but some of it is probably ... Extended-spectrum beta-lactamase-producing E. coli (ESBL E. coli) are highly resistant to an array of antibiotics, and ...
Falagas ME, Matthaiou DK, Vardakas KZ (December 2006). "Fluoroquinolones vs beta-lactams for empirical treatment of ... however this indication is no longer considered to be effective by some experts due to bacterial resistance) Prostatitis due to ... to be contraindicated for the treatment of certain sexually transmitted diseases by some experts due to bacterial resistance. ...
... and beta-lactams. In recognition of her contributions to the field of microbiology, Silver was elected as a fellow of the ... "Origin and direction of replication of the drug resistance plasmid R100.1 and of a resistance transfer factor derivative in ... Her research includes seminal contributions in the understanding of the mode of action and mechanism of resistance of ... She has contributed to the discovery of new antibacterials to overcome antibiotic resistance and toxicity issues through ...
It may also be used in hyperthyroidism if beta blockers cannot be used. It is taken by mouth or injection into a vein. When ... which reduces peripheral resistance and afterload, though not as potent as the dihydropyridine (DHP) calcium channel blockers. ... Lactams, Acetate esters, Chemical substances for emergency medicine, Wikipedia medicine articles ready to translate, ... Intravenous diltiazem should be used with caution with beta-blockers because, while the combination is most potent at reducing ...
Staphylococcal resistance to penicillin is mediated by penicillinase (a form of beta-lactamase) production: an enzyme that ... This allows for resistance to all β-lactam antibiotics, and obviates their clinical use during MRSA infections. Studies have ... S. aureus biofilms also have high resistance to host immune response. Though the exact mechanism of resistance is unknown, S. ... Because of the high level of resistance to penicillins and because of the potential for MRSA to develop resistance to ...
Amoxicillin/clavulanic acid, which includes the beta lactam amoxicillin with the suicide inhibitor clauvanic acid, which helps ... Antibiotic combinations are increasingly important because of antimicrobial resistance. This means that individual antibiotics ... Examples of combinations include: Amoxicillin/clavulanic acid, which includes the beta lactam amoxicillin with the suicide ... the amoxicillin overcome the action of beta lactamase because a person may be infected with more than one microbe ...
The target molecules are peptidoglycan cross-linking enzymes (e.g. transpeptidases and carboxypeptidases) which can bind beta- ... Beta-lactam antibiotics share the structural feature of a beta-lactam ring. This feature is responsible for inhibition of ... Beta-lactam antibiotics share the structural feature of a beta-lactam ring. This feature is responsible for inhibition of ... Mechanisms and clinical significance of resistance to new beta-lactam antibiotics. Livermore DM, Wood MJ. Livermore DM, et al. ...
... beta-lactamase, beta-... Cloning vector pBRINT encoding chloramphenicol resistance, beta-lactamase, beta-lactamase transporter ... Cloning vector pBRINT encoding chloramphenicol resistance, beta-lactamase, beta-lactamase transporter, ampicillin resistance, ...
The conjugative transfer of plasmids by type IV secretion systems is a major contributor to antimicrobial resistance gene ... The strategy presented here is generally applicable for the structure-based design of inhibitors of antimicrobial resistance ... Novel strategies are urgently needed to understand and inhibit antimicrobial resistance gene transmission that is ... The increasing frequency of antimicrobial resistance is a problem of global importance. ...
Mutations in PBP4 or its promoter also contribute to the resistance. The mechanism of resistance to beta-lactams in mec- ... In addition, there are mec-independent pathways of beta-lactam resistance that could be found in *S. aureus*. In particular, ... virtually providing resistance to all beta-lactams, with the exception of antiMRSA cephalosporins. Mutations in PBP2a ... associated with an increase in the intracellular concentration of c-diAMP messengers that promote resistance to beta-lactams, ...
We tested for resistance to beta-lactams in S. aureus isolated from phone screens of senior dentistry students who were ... The S. aureus genes were identified by means of a PCR and the antibiotic resistance by using the Kirby Bauer's diffusion ... Phenotypic resistance to penicillin and oxacillin manifested in 12 and 7 strains, respectively. We conclude that dental ... Resistance to beta-lactams in Staphylococcus aureus isolated from cell phone screens of dentistry students based on an ...
RF010 - Beta-Lactam-Resistance Mechanisms (AAR Rapid Fire Presentations). 370 A-F, GRB Center. Arjun Prasad, PhD. The ... P002 - AAR01 Surveillance of Antimicrobial Resistance in Clinical Isolates: Beta-Lactamases. Exhibit/Poster Hall BCD. Michael ... Gelio Alves: Pathogen and Antibiotic Resistance Detection via MiCIds workflow. 8:45 a.m. - 8:50 a.m.. ... Gelio Alves: Pathogen and Antibiotic Resistance Detection via MiCIds workflow. 1:00 p.m. - 2:00 p.m.. Arjun Prasad: Pathogen ...
Beta-lactam resistance among Haemophilus influenzae isolates in Poland. J Glob Antimicrob Resist. 2017 Aug 14. [QxMD MEDLINE ... Ampicillin resistance in Haemophilus influenzae from COPD patients in the UK. Int J Chron Obstruct Pulmon Dis. 2017. 12:1507- ... Hu F, Zhu D, Wang F, Morrissey I, Wang J, Torumkuney D. Results from the Survey of Antibiotic Resistance (SOAR) 2009-11 and ... Fluoroquinolone resistance in Haemophilus influenzae from nursing home residents in Taiwan: correlation of MICs and mutations ...
... database for detecting first step beta lactam resistance. *Presence or absence of various surface proteins, including certain ... MIC predictions, including PBP typing system for determining beta lactam antibiotic MICs ... PBP2x amino acid sequence types to monitor for possible emergence of beta lactam nonsusceptibility ... Resistance mechanisms and all minimum inhibitory concentrations (MICs) on panel (and others); ...
Drug Resistance, Microbial. fr. dc.subject.mesh. Penicillin Resistance. fr. dc.subject.mesh. beta-Lactam Resistance. fr. ...
ESBL enzymes create resistance within the body to most beta-lactam antibiotics, including penicillins, cephalosporins, and ... Daily sampling revealed that all participants had acquired extended-spectrum beta-lactamases (ESBL) at some time point during ...
Trends in beta-lactam resistance among Enterobacteriaceae. Clin Infect Dis. 1998;27(Suppl 1):S100-6. DOIPubMedGoogle Scholar ... Transfer of Resistance in vitro. One CTX-M-9-positive isolate transferred its resistance by in vitro conjugation to E. coli ... Sabaté M, Miró E, Navarro F, Vergés C, Aliaga R, Mirelis B, β-Lactamases involved in resistance to broad-spectrum ... are associated with antibiotic resistance, including antibiotic resistance to ESCs (7-11). Available data regarding other ...
beta-Lactam resistance. 23.68. map00311. Penicillin and cephalosporin biosynthesis. 23.68. map02020. Two-component system - ...
Categories: beta-Lactam Resistance Image Types: Photo, Illustrations, Video, Color, Black&White, PublicDomain, ...
beta-Lactam resistance in gram-negative bacteria: global trends and clinical impact. Clin Infect Dis. 1992 Nov. 15(5):824-39. [ ... beta-Lactamases in laboratory and clinical resistance. Clin Microbiol Rev. 1995 Oct. 8(4):557-84. [QxMD MEDLINE Link]. ... AmpC beta-lactamases. Clin Microbiol Rev. 2009 Jan. 22(1):161-82, Table of Contents. [QxMD MEDLINE Link]. [Full Text]. ... Resistance in gram-negative bacteria: enterobacteriaceae. Am J Med. 2006 Jun. 119(6 Suppl 1):S20-8; discussion S62-70. [QxMD ...
Prevalence and mechanisms of broad-spectrum beta-lactam resistance in Enterobacteriaceae: a childrens hospital experience.. ... Emerging oseltamivir resistance in seasonal and pandemic influenza A/H1N1.. 21684202 Journal of clinical virology : the ... Oseltamivir pharmacokinetics, dosing, and resistance among children aged andlt;2 years with influenza.. 23230059 The Journal of ... Mutations linked to drug resistance, human immunodeficiency virus type 1 biologic phenotype and their association with disease ...
... beta-Lactam Resistance/genetics; beta-Lactamases/genetics*; beta-Lactamases/metabolism ... Our study revealed 1) high CTX resistance (66.1%) in farmed broiler chickens, 2) an increase in CTX resistance over time in ... Title: High Prevalence of Extended-Spectrum Beta-Lactamase CTX-M-Producing Escherichia coli in Small-Scale Poultry Farming in ... Abstract: Small-scale farming may have large impacts on the selection and spread of antimicrobial resistance to humans. We ...
Further, statistically significant differences in the distribution of beta-lactam MICs were observed betw … ... bro {beta}-lactamase and antibiotic resistances in a global cross-sectional study of Moraxella catarrhalis from children and ... Consistently higher beta-lactam MICs were observed for M. catarrhalis isolates originating in the Far East. Significant ... Further, statistically significant differences in the distribution of beta-lactam MICs were observed between different world ...
Cross-hypersensitivity among beta-lactam antibacterial drugs may occur in up to 10% of patients with a history of penicillin ... Resistance Methicillin-resistant staphylococci and most isolates of enterococci are resistant to cephalexin. Cephalexin is not ... Ask the patient about any previous hypersensitivity reactions to cephalexin, other beta-lactams (including cephalosporins) or ... Serious hypersensitivity (anaphylactic) reactions: Prior to use, inquire regarding history of hypersensitivity to beta-lactam ...
These include broad-spectrum and beta lactams, aminoglycosides, and sulfonamides. Only the quinolones are not associated with ... Multiple drug resistance is usually associated with extrachromosomal transfer of plasmids.7,8 These plasmids incorporate not ... In addition, the bacteria frequently show multiple drug resistance because of the patients exposure to antimicrobials and the ... Initially, antibiotic therapy must be broad-spectrum to cover multiple organisms and drug resistance. ...
... the percent of isolates that are resistant to combinations of aminoglycoside and beta lactam drugs. (F) Of those cases that are ... Antimicrobial resistance Is the Subject Area "Antimicrobial resistance" applicable to this article? Yes. No. ... Antibiotic resistance Is the Subject Area "Antibiotic resistance" applicable to this article? Yes. No. ... Comparatively, rates of resistance to ceftazidime and meropenem are variable across geographic regions: Rates of resistance to ...
Anaerobes manifest 3 major mechanisms of resistance to beta-lactam antibiotics: inactivating enzymes, mainly beta-lactamases, ... The combination of beta-lactamase inhibitors (eg, clavulanic acid, sulbactam, tazobactam) with a beta-lactam antibiotic (eg, ... Although the patterns differ by region, B fragilis resistance to clindamycin is increasing worldwide. Resistance of the B ... and combinations of a penicillin and beta-lactamase inhibitors. Resistance to other agents varies. ...
4. [Resistance to newer beta-lactams and related ESBL types in gram-negative nosocomial isolates in Turkish hospitals: results ... 5. [Antibiotic susceptibility rates and beta-lactam resistance mechanisms of Pseudomonas aeruginosa strains].. Aktaş Z; Satana ... 3. [Investigation of the frequency of PER-1 type beta-lactamase and antimicrobial resistance rates in nosocomial isolates of ... and antibacterial resistance profiles of extended spectrum beta lactamase (ESBL) producing Pseudomonas aeruginosa among burnt ...
A cell wall damage response mediated by a sensor kinase/response regulator pair enables beta-lactam tolerance. Proc Natl Acad ... A Transposon Screen Identifies Genetic Determinants of Vibrio cholerae Resistance to High-Molecular-Weight Antibiotics. ...
... while antimicrobial resistance genes (ARGs) for β-lactam (blaCTX-M-65) and colistin (mcr-1) resistance were detected in ... We identified a genetic antimicrobial resistance cassette carrying the ant(3)-Ia, dfrA15, qacE, and sul1 genes associated with ... beta-lactams, fluoroquinolones, and macrolides [47,48]. Resistance to aminoglycosides, trimethoprim, and sulfonamide may be ... while antimicrobial resistance genes (ARGs) for β-lactam (blaCTX-M-65) and colistin (mcr-1) resistance were detected in ...
... but they are able to inhibit the enzyme in part responsible for the resistance of M. tuberculosis to beta-lactam antibiotics. ... Combination of beta-Lactam Antibiotics and beta-Lactamase Inhibitors. Amoxicillin is a semisynthetic beta-lactam antibiotic, an ... Combination of beta-Lactam Antibiotics and beta-Lactamase Inhibitors. The New Macrolides. Initial Treatment Regimens. ... Beta-lactam antibiotics penetrate poorly into mammalian cells, and this characteristic may limit the effectiveness of these ...
Extended spectrum beta-lactamases mediating resistance to extended spectrum beta-lactam antibiotics among Gram-negative ... Antibiotic resistance. Table 3 reveals that antibiotic resistance rates of clinical isolates in Egypt and Saudi Arabia were ... Metallo-β-lactamases: a last frontier for beta-lactams? Lancet Infectious Diseases, 2011, 11:381-393. ... it can acquire resistance via mutations and harbouring integrons with multiple resistance genes such as those coding for ...
  • Beta-lactam antibiotics include the penicillins, cephalosporins, oxacephems (moxalactam), carbapenems (imipenem) and monobactams (azthreonam)--all with a common beta-lactam ring. (
  • Beta-lactam antibiotics block the synthesis and growth of the bacterial cell wall by binding to penicillin-binding proteins on the cytoplasma membrane. (
  • The bacteria may escape the effect of beta-lactam antibiotics by reducing the permeability of the cell wall (gramnegative bacteria), by producing beta-lactamases, by reducing the affinity for beta-lactams in their penicillin-binding proteins, or by developing tolerance to beta-lactam antibiotics. (
  • Anaerobic bacteria and beta-lactam antibiotics. (
  • Mechanisms and clinical significance of resistance to new beta-lactam antibiotics. (
  • The review presents the current view on the different resistance mechanisms of Staphylococcus aureus to beta-lactams, which are ones of the main antibiotics of choice for the treatment of staphylococcal infections. (
  • 6. Brown D.F.J., Reynolds P.E. Intrinsic resistance to β-lactam antibiotics in Staphylococcus aureus. (
  • The model suggests that simple differences in the impact of antibiotic exposure does not differ according to the natural history of colonization, interhuman contact, and expo- mechanism of resistance and do not consider the particular nat- sure to -lactam antibiotics explain major differences in the epi- ural history of the colonization of the bacterial species. (
  • Therefore, -lactam antibiotics, such as penicillin G, bind to PBPs in better understanding of S. pneumoniae resistance selection and the bacterial cell wall. (
  • Our study site is a remote region with historically low resistance levels of third-generation antibiotics such cefotaxime (CTX), a clinically relevant antibiotic, in both poultry and humans. (
  • Our study revealed 1) high CTX resistance (66.1%) in farmed broiler chickens, 2) an increase in CTX resistance over time in backyard chicken not fed antibiotics (2.3-17.9%), and 3) identical blaCTX-M sequences from human and chicken bacteria, suggesting a spillover event. (
  • ESBL enzymes create resistance within the body to most beta-lactam antibiotics, including penicillins, cephalosporins, and aztreonam. (
  • 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. (
  • The most common way that bacteria become invulnerable to antibiotics is through the transfer of resistance genes from other bacteria. (
  • Some of these plasmids contain genes that confer resistance to commonly used antibiotics, including beta-lactam drugs like penicillin and cephalosporins and fluoroquinolones like ciprofloxacin (Cipro). (
  • Environmental pollution by antibiotics and by antibiotic resistance determinants. (
  • [1] Nitrofurantoin was widely used to treat lower urinary tract infections until the 1970s, when trimethoprim-sulfamethoxazole and newer beta-lactam antibiotics became available. (
  • Increasing resistance to newer antibiotics coinciding with an increasing prevalence of extended-spectrum beta-lactamase (ESBL) producing bacteria has led to a resurgence in the prescriptions of nitrofurantoin. (
  • S. aureus has the ability to develop resistance to antimicrobials (AMR), highlighting methicillin-resistant strains (MRSA), which have resistance to all beta-lactam antibiotics, except to the fifth-generation cephalosporins. (
  • However, frequent use of antibiotics for bronchitis with COPD increases the risk of antibiotic resistance of microorganisms. (
  • Drugs of choice for the treatment of bacterial bronchitis are macrolide (Erythromycin, Spiramycin, Clarithromycin) and beta-lactam (Penicillins, Cephalosporins, Carbapenems, Monobactams) antibiotics. (
  • Beta-lactam antibiotics are highly effective against typical bacterial pathogens. (
  • The genes made a laboratory strain of Escherichia coli bacteria resistant to one of four types of antibiotics - beta-lactams (like penicillin), aminoglycosides (like kanamycin), tetracycline, or chloramphenicol. (
  • The team also found an entire new family of AR genes that confer resistance to chloramphenicol antibiotics, which are commonly used to treat respiratory infections in livestock. (
  • The increasing frequency of antimicrobial resistance is a problem of global importance. (
  • Novel strategies are urgently needed to understand and inhibit antimicrobial resistance gene transmission that is mechanistically related to bacterial virulence functions. (
  • The conjugative transfer of plasmids by type IV secretion systems is a major contributor to antimicrobial resistance gene transfer. (
  • The strategy presented here is generally applicable for the structure-based design of inhibitors of antimicrobial resistance gene transfer and of bacterial virulence. (
  • Small-scale farming may have large impacts on the selection and spread of antimicrobial resistance to humans. (
  • Additionally, the IDSA recently published guidance for treating antimicrobial resistant gram negative pathogens with a focus on ESBL producing and carbapenem-resistant Enterobacterales as well as Pseudomonas aeruginosa with difficult to treat resistance patterns. (
  • Update on Taxonomy, Clinical Aspects, and Emerging Antimicrobial Resistance. (
  • Santajit S, Indrawattana N. Mechanisms of Antimicrobial Resistance in ESKAPE Pathogens. (
  • Rice LB. Federal funding for the study of antimicrobial resistance in nosocomial pathogens: no ESKAPE. (
  • Antimicrobial resistance among Gram-negative bacilli causing infections in intensive care unit patients in the United States between 1993 and 2004. (
  • Intensive Care Antimicrobial Resistance Epidemiology (ICARE) Surveillance Report, data summary from January 1996 through December 1997: A report from the National Nosocomial Infections Surveillance (NNIS) System. (
  • In vitro susceptibilities of aerobic and facultatively anaerobic Gram-negative bacilli isolated from patients with intra-abdominal infections worldwide: 2004 results from SMART (Study for Monitoring Antimicrobial Resistance Trends). (
  • Antimicrobial resistance patterns may vary. (
  • The major increase in antimicrobial resistance for AGNB is of clindamycin, cefoxitin, and cefotetan. (
  • Multidrug antimicrobial resistance (MDR) in anaerobes including AGNB is increasing. (
  • 7. [The composition and antimicrobial resistance of isolates from lower respiratory tract and blood in hospitalized patients in respiratory ward: a multicenter national study in China]. (
  • 14. Maternal vaginal colonization with selected potential pathogens of neonatal sepsis in the era of antimicrobial resistance, a single center experience from Sri Lanka. (
  • Since these infections are usually acquired in a health-care setting where antimicrobial use is pervasive, bacterial virulence and antimicrobial resistance is increased. (
  • We estimated the potential impact of such vaccination on cases and deaths of K . pneumoniae neonatal sepsis and project the global effects of routine immunization of pregnant women with the K . pneumoniae vaccine as antimicrobial resistance (AMR) increases. (
  • To the best of our knowledge, before this report no foodborne carbapenemase-producing organisms had been identified in Canada and the United States, although the scope of antimicrobial drug resistance surveillance programs is limited to major agricultural products-- poultry, beef, and pork. (
  • Therefore, coastal ecosystems may become increasingly important as reservoirs of or sentinels for infectious organisms 2 and antimicrobial resistance (AMR). (
  • While it is well known that neonates are vulnerable to invasive infection with MRSA, there is a real shortage of neonatal data on the profiles of MRSA infection and antimicrobial resistance rates. (
  • Penicillin-binding proteins and beta-lactamases: their effects on the use of cephalosporins and other new beta-lactams. (
  • Another one is the presence of an alternative penicillin-binding protein (PBP2a), which is the main marker of methicillinresistant S. aureus (MRSA), virtually providing resistance to all beta-lactams, with the exception of antiMRSA cephalosporins. (
  • In particular, mutations in the gdpP are associated with an increase in the intracellular concentration of c-diAMP messengers that promote resistance to beta-lactams, including anti-MRSA cephalosporins. (
  • Currently, there are several mechanisms of resistance such as production of staphylococcal beta-lactamase (blaZ), which provides resistance to penicillins and aminopenicillins. (
  • Genomic identification of cryptic susceptibility to penicillins and beta-lactamase inhibitors in methicillin-resistant Staphylococcus aureus. (
  • Clinical aerogenes showed resistance to the aminoglycosides and data on these patients were collected, and the ulcers beta-lactams. (
  • These include broad-spectrum and beta lactams, aminoglycosides, and sulfonamides. (
  • E. coli isolates of this study contained genes causing resistance against aminoglycosides, beta-lactams, macrolides-lincosamide-streptogramin, sulphonamides, tetracyclines and trimethoprim. (
  • Initially, antibiotic therapy must be broad-spectrum to cover multiple organisms and drug resistance. (
  • In addition, the bacteria frequently show multiple drug resistance because of the patients' exposure to antimicrobials and the fact that the bacteria are usually acquired within a hospital or nursing home setting. (
  • Multiple drug resistance is usually associated with extrachromosomal transfer of plasmids. (
  • Ethambutol (or streptomycin in children too young to be monitored for visual acuity) should also be included until the results of drug susceptibility studies are available, unless there is little possibility of drug resistance (see Section 1 above). (
  • A 4-mo regimen of isoniazid and rifampin is acceptable therapy for adults who have active tuberculosis and who are sputum-smear and culture negative, if there is little possibility of drug resistance (see Section 1 above). (
  • The use of fixed drug combinations may enhance patient adherence and may reduce the risk of inappropriate monotherapy, and it may prevent the development of secondary drug resistance. (
  • Among other items, the squid was purchased from a Chinese grocery store in Saskatoon, Canada, in January 2014 as part of a drug-resistance surveillance pilot study. (
  • By better understanding the nature of drug resistance plasmids in urban wetlands, Cummings hopes to aid future efforts to prevent their potential spread among bacteria that cause human disease. (
  • The mechanism of resistance to beta-lactams in mec-negative S. aureus (borderline oxacillin-resistant S. aureus , BORSA) is associated with the mutations in PBP1, PBP2, PBP3, and PBP4 or the overexpression of staphylococcal beta-lactamase. (
  • Original Article were used in determining if an isolate was resistant or coli , and Clostridium species had resistance rates of 50%, susceptible to each antibiotic. (
  • However, in addition to the B fragilis group, which is resistant to penicillin, other AGNB show increased resistance. (
  • however, they are not completely resistant to beta-lactamase. (
  • 7,8 These plasmids incorporate not only resistance to the drug the patient is receiving but also multiple agents that share this plasmid-mediated resistant capability. (
  • Resistance rates to carbapenems are increasing most rapidly and 22.43% [95th percentile Bayesian credible interval (CrI): 5.24 to 41.42] of neonatal sepsis deaths are caused by meropenem-resistant K . pneumoniae . (
  • Multiple-drug-resistant tuberculosis (i.e., resistance to at least isoniazid and rifampin) presents difficult treatment problems. (
  • Although the organism was not extensively resistant, it was resistant to all Beta-lactam drugs tested, including ertapenem. (
  • Within 48 hours after collection swabs were streaked onto different plates to screen for Methicillin Resistant Staphylococcus aureus (MRSA), Extended Spectrum Beta-Lactamase (ESBL) and B-lactamase hyper producing gram-negative bacteria, and Vancomycin Resistant Enterococci (VRE). (
  • High Prevalence of Extended-Spectrum Beta-Lactamase CTX-M-Producing Escherichia coli in Small-Scale Poultry Farming in Rural Ecuador. (
  • 5. Kuhl S.A., Pattee P.A., Baldwin J.N. Chromosomal map location of the methicillin resistance determinant in Staphylococcus aureus. (
  • To compare and contrast the geographic and demographic distribution of bro beta-lactamase and antibiotic MIC(50/90) for 1440 global Moraxella catarrhalis isolates obtained from children and adults between 2001 and 2002. (
  • Consistently higher beta-lactam MICs were observed for M. catarrhalis isolates originating in the Far East. (
  • E. coli isolates found in them are closely related to those found in human and contain resistance genes that are also found in human isolates. (
  • The B fragilis group is almost uniformly susceptible to metronidazole, carbapenems, chloramphenicol, and combinations of a penicillin and beta-lactamase inhibitors. (
  • When susceptibility test results show susceptibility to amoxicillin, indicating no beta-lactamase production, Amoxicillin and Clavulanate Potassium for Oral Suspension should not be used. (
  • In addition, there are mec-independent pathways of beta-lactam resistance that could be found in S. aureus . (
  • We tested for resistance to beta-lactams in S. aureus isolated from phone screens of senior dentistry students who were involved in pre-professional clinical practice. (
  • The S. aureus genes were identified by means of a PCR and the antibiotic resistance by using the Kirby Bauer's diffusion technique. (
  • Increased antibiotic pressure may select for beta-lactam resistance among other bacteria as well, such as staphylococci, streptococci, Haemophilus influenzae, meningococci and gonococci. (
  • Streptococcus pneumoniae and Neisseria meningitidis selection pressure borne by these bacteria, as young children have very similar mechanisms of resistance to penicillin G. are treated more frequently than young adults. (
  • Although this organism may not be a pathogen, its contribution to the resistance and the potential for lateral gene transfer to clinically relevant bacteria is certainly a cause for concern. (
  • These habitats provide ideal conditions for bacteria from diverse sources, such as human sewage, animal waste and naturally occurring plant and soil microorganisms, to swap genes and spread antibiotic resistance, he notes. (
  • Bacteria living in the human body can trade resistance genes, too. (
  • Gautam Dantas of Washington University School of Medicine in St. Louis is investigating how resistance develops in and spreads among the bacteria that colonize the human gut during the first 2 years of life. (
  • This is a way to detect resistance genes before they [transfer into disease-causing bacteria and] become a problem,' says Dantas. (
  • Manure from dairy cows, which is commonly used as a farm soil fertilizer, contains a surprising number of newly identified antibiotic resistance genes from the cows' gut bacteria. (
  • The findings, reported in mBio® the online open-access journal of the American Society for Microbiology, hints that cow manure is a potential source of new types of antibiotic resistance genes that transfer to bacteria in the soils where food is grown. (
  • Thousands of antibiotic resistance (AR) genes have already been identified, but the vast majority of them don't pose a problem when found in harmless bacteria. (
  • Some manure bacteria might be pathogenic to humans, so if they acquire antibiotic resistance, they could pose a problem. (
  • Alternatively, benign bacteria in manure might transfer resistance genes to pathogens at any point along the path - in manure, soil, food, or humans. (
  • Indeed, other gram-negative enteric pathogens, notably Salmonella enterica , are a frequent cause of foodborne disease and, increasingly, are associated with antibiotic resistance, including antibiotic resistance to ESCs ( 7 - 11 ). (
  • Antibiotic resistance can turn once-manageable infections into 'superbug' diseases that are difficult-and sometimes impossible-to treat. (
  • This study aimed to analyze the clinical characteristics and antibiotic resistance profiles of invasive MRSA infections and determine risk factors associated with invasive MRSA infections in newborn inpatients. (
  • Herein, we analyzed the clinical and antibiotic resistance profiles of invasive MRSA infections in neonatal from eleven hospitals within the Infectious Diseases Surveillance of Pediatrics (ISPED) group of China over a two-year period (2018-2019) and factors related to severity. (
  • The global emergence of carbapenemase-producing organisms is a public health emergency because these enzymes confer resistance to nearly all Beta-lactam drugs and are often associated with multidrug or pandrug resistance. (
  • The observed distribution of resistance plasmids and β-lactamase genes in several clones indicates a high degree of horizontal transfer. (
  • David Cummings studies the role of urban storm water in spreading genes for antibiotic resistance in natural environments. (
  • David Cummings of Point Loma Nazarene University in San Diego searches for plasmids bearing resistance genes in sediment samples from several urban wetlands. (
  • Dantas is studying the development of the complete collection of resistance genes in the gut-dubbed the resistome-in healthy sets of twins and in infants with very low birthweights. (
  • Its use in humans and animals leads to the selection of resistance genes. (
  • Similar resistance genes found in humans are also found in pristine ecosystems without any record of antibiotic contamination. (
  • In addition, the presence of resistance genes was determined. (
  • Significant correlations in MICs were observed for several antibiotic combinations, including all five beta-lactams with each other, and among the two quinolones. (
  • Further, statistically significant differences in the distribution of beta-lactam MICs were observed between different world regions, particularly with respect to the Far East. (
  • There is an urgent need for expanded resistance surveillance for carbapenemase-producing organisms and their resistance plasmids in food products that are not captured under current programs. (
  • We describe a mathematical model of the emergence and diffusion of bacterial resistance in the community. (
  • Here are just a few examples of what they're exploring and how it could aid efforts to curb the emergence of resistance. (
  • Prior to use, inquire regarding history of hypersensitivity to beta-lactam antibacterial drugs. (
  • Streptococcus pneumoniae and Neisseria meningitidis have is specific to the mechanism of resistance to penicillin G com- very similar mechanisms of resistance to penicillin G, which mon to S. pneumoniae and N. meningitidis and mediated by the are mediated by the decreased affinity of penicillin-binding decrease in affinity of their PBPs. (
  • Phenotypic resistance to penicillin and oxacillin manifested in 12 and 7 strains, respectively. (
  • Worldwide dissemination of the Klebsiella pneumoniae , VIM, OXA, and New Delhi metallo-Beta-lactamase type carbapenemases among humans has been facilitated by intercontinental passenger travel, but the role of the global food trade in this dissemination has not been investigated. (
  • 10. Bush K., Bradford P.A. beta-Lactams and beta-Lactamase inhibitors: an overview. (
  • MRSA outbreaks remain an ongoing concern in neonatal care and are increasingly complicated by high rates of resistance. (
  • This review describes those and other phenotypes, the features of resistance mechanisms, clinical significance, as well as the possibilities for phenotypic detection. (
  • Daily sampling revealed that all participants had acquired extended-spectrum beta-lactamases (ESBL) at some time point during their overseas stay. (
  • The distribution of resistance levels to predict future trends (13). (
  • MiCId: A workflow with accurate statistical significance for rapid identification of microorganisms, and antibiotic resistance proteins, and estimation of biomass. (
  • Researchers think that nitrofurantoin's continued effectiveness and minimal resistance patterns are partly attributable to its minimal effect on bowel flora. (
  • lethal, meningococcal resistance is a major concern. (
  • We're hoping this study will open up a larger field of surveillance, to start looking at new types of resistance before they show up in the clinic," says Handelsman. (
  • demiology of resistance of S. pneumoniae and N. meningitidis . (
  • In both S. pneumoniae and N. meningi- establishing whether meningococcal resistance could increase tidis , the main mechanism of penicillin G resistance is mediat- are important. (
  • The average colonization duration of S. of the pharynx of intragenic sequences, which leads to the syn- pneumoniae is approximately 2 to 3 months (8), whereas dura- thesis of mosaic PBPs and confers higher levels of resistance tion is approximately 10 months for N. meningitidis (9). (
  • By to anticipate its trends in penicillin G-resistance selection contrast, for N. meningitidis , reports of high levels of resistance according to antibiotic exposure. (