Lactams: Cyclic AMIDES formed from aminocarboxylic acids by the elimination of water. Lactims are the enol forms of lactams.Cyclacillin: A cyclohexylamido analog of PENICILLANIC ACID.beta-Lactams: 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.Superinfection: 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.Aminoglycosides: Glycosylated compounds in which there is an amino substituent on the glycoside. Some of them are clinically important ANTIBIOTICS.Anti-Bacterial Agents: Substances that reduce the growth or reproduction of BACTERIA.Penicillin Resistance: Nonsusceptibility of an organism to the action of penicillins.Cyclization: Changing an open-chain hydrocarbon to a closed ring. (McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)Randomized Controlled Trials as Topic: 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.alpha-MSH: 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.Heterocyclic Compounds, 1-Ring: 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.Interleukin-1beta: 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.Muramic Acids: 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)Stereoisomerism: 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)beta 2-Microglobulin: 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.Molecular Structure: 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.Amination: 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.Cleome: A plant genus of the family CAPPARACEAE that contains cleogynol and 15alpha-acetoxycleomblynol (dammaranes) and 1-epibrachyacarpone (a triterpene), and ISOTHIOCYANATES.Receptors, Melanocortin: 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.Receptors, Adrenergic, beta: 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.Integrin beta3: 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.IminesStreptothricins: 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.Magnetic Resonance Spectroscopy: 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).Transforming Growth Factor beta: 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.Structure-Activity Relationship: 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.Alkenes: Unsaturated hydrocarbons of the type Cn-H2n, indicated by the suffix -ene. (Grant & Hackh's Chemical Dictionary, 5th ed, p408)Carboxylic Acids: 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.Streptomyces: 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.Amides: 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)Drug Design: 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.Bicyclo Compounds, Heterocyclic: 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)Integrin alpha5beta1: 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.Peptides, Cyclic: 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).Integrin beta4: 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.Chromatography, Paper: 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).Integrin alpha6beta4: 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.Integrin beta Chains: 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.beta 2-Glycoprotein I: 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.Aza CompoundsModels, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Integrin alpha4beta1: 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.Indium Radioisotopes: 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.Molecular Conformation: The characteristic three-dimensional shape of a molecule.Encyclopedias as Topic: Works containing information articles on subjects in every field of knowledge, usually arranged in alphabetical order, or a similar work limited to a special field or subject. (From The ALA Glossary of Library and Information Science, 1983)Imino Sugars: Sugars in which the OXYGEN is replaced by a NITROGEN atom. This substitution prevents normal METABOLISM resulting in inhibition of GLYCOSIDASES and GLYCOSYLTRANSFERASES.Monobactams: Monocyclic, bacterially produced or semisynthetic beta-lactam antibiotics. They lack the double ring construction of the traditional beta-lactam antibiotics and can be easily synthesized.AzetidinesClavulanic Acid: Clavulanic acid and its salts and esters. The acid is a suicide inhibitor of bacterial beta-lactamase enzymes from Streptomyces clavuligerus. Administered alone, it has only weak antibacterial activity against most organisms, but given in combination with other beta-lactam antibiotics it prevents antibiotic inactivation by microbial lactamase.beta-Lactamases: Enzymes found in many bacteria which catalyze the hydrolysis of the amide bond in the beta-lactam ring. Well known antibiotics destroyed by these enzymes are penicillins and cephalosporins.Clavulanic Acids: Acids, salts, and derivatives of clavulanic acid (C8H9O5N). They consist of those beta-lactam compounds that differ from penicillin in having the sulfur of the thiazolidine ring replaced by an oxygen. They have limited antibacterial action, but block bacterial beta-lactamase irreversibly, so that similar antibiotics are not broken down by the bacterial enzymes and therefore can exert their antibacterial effects.Amoxicillin: A broad-spectrum semisynthetic antibiotic similar to AMPICILLIN except that its resistance to gastric acid permits higher serum levels with oral administration.Microbial Sensitivity Tests: Any tests that demonstrate the relative efficacy of different chemotherapeutic agents against specific microorganisms (i.e., bacteria, fungi, viruses).

Mechanisms of beta-lactam resistance amongst Pseudomonas aeruginosa isolated in an Italian survey. (1/1422)

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)

Comparison of activities of broad-spectrum beta-lactam compounds against 1,128 gram-positive cocci recently isolated in cancer treatment centers. (2/1422)

We report the in vitro activities of broad-spectrum beta-lactam antimicrobials tested against 1,128 gram-positive pathogens recently isolated from cancer patients. Cefepime and imipenem were more active than ceftazidime and ceftriaxone against these organisms. Only vancomycin demonstrated reliable activity against oxacillin-resistant staphylococci, Enterococcus spp., and Corynebacterium spp. The spectrum of gram-positive organisms against which cefepime and imipenem have activity provides an advantage over ceftazidime as empiric therapy for cancer patients, potentially reducing the need for the empiric addition of glycopeptides.  (+info)

Clavulanic acid inhibition of beta-lactamase I from Bacillus cereus 569/H. (3/1422)

Inactivation of beta-lactamase I by clavulanic acid was investigated. Clavulanic acid induced inhibition of the enzyme was found to be progressive with time. Benzylpenicillin provided protection against the adverse effects of the inhibitor initially, however, the enzyme was irreversibly inhibited in a progressive manner even in the presence of substrate. Reaction of beta-lactamase I with clavulanic acid, in the presence of ampicillin, led to a very rapid inactivation of the enzyme.  (+info)

Kinetic properties and metal content of the metallo-beta-lactamase CcrA harboring selective amino acid substitutions. (4/1422)

The crystal structure of the metallo-beta-lactamase CcrA3 indicates that the active site of this enzyme contains a binuclear zinc center. To aid in assessing the involvement of specific residues in beta-lactam hydrolysis and susceptibility to inhibitors, individual substitutions of selected amino acids were generated. Substitution of the zinc-ligating residue Cys181 with Ser (C181S) resulted in a significant reduction in hydrolytic activity; kcat values decreased 2-4 orders of magnitude for all substrates. Replacement of His99 with Asn (H99N) significantly reduced the hydrolytic activity for penicillin and imipenem. Replacement of Asp103 with Asn (D103N) showed reduced hydrolytic activity for cephaloridine and imipenem. Deletion of amino acids 46-51 dramatically reduced both the hydrolytic activity and affinity for all beta-lactams. The metal binding capacity of each mutant enzyme was examined using nondenaturing electrospray ionization mass spectrometry. Two zinc ions were observed for the wild-type enzyme and most of the mutant enzymes. However, for the H99N, C181S, and D103N enzymes, three different zinc content patterns were observed. These enzymes contained two zinc molecules, one zinc molecule, and a mixture of one or two zinc molecules/enzyme molecule, respectively. Two enzymes with substitutions of Cys104 or Cys104 and Cys155 were also composed of mixed enzyme populations.  (+info)

OXA-17, a further extended-spectrum variant of OXA-10 beta-lactamase, isolated from Pseudomonas aeruginosa. (5/1422)

Pseudomonas aeruginosa isolates 871 and 873 were isolated at Hacettepe University Hospital in Ankara and were highly resistant to ceftazidime (MIC, 128 microg/ml). Each produced three beta-lactamases, with pIs of 5.3, 6.1, and 7.9. The beta-lactamase with a pI of 5.3 was previously shown to be PER-1 enzyme. The antibiograms of the isolates were not entirely explained by production of PER-1 enzyme, insofar as ceftazidime resistance was incompletely reversed by clavulanate. The enzymes with pIs of 6.1 and 7.9 were therefore investigated. The enzyme with a pI of 6.1 proved to be a novel mutant of OXA-10, which we designated OXA-17, and had asparagine changed to serine at position 73 of the protein. When cloned into Escherichia coli XL1-blue, OXA-17 enzyme conferred greater resistance to cefotaxime, latamoxef, and cefepime than did OXA-10, but it had only a marginal (two- to fourfold) effect on the MIC of ceftazidime. This behavior contrasted with that of previous OXA-10 mutants, specifically OXA-11, -14, and -16, which predominately compromise ceftazidime. Extracted OXA-17 enzyme had relatively greater activity than OXA-10 against oxacillin, cloxacillin, and cefotaxime but, in terms of kcat/Km, it had lower catalytic efficiency against most beta-lactams. The enzyme with a pI of 7.9 was shown by gene sequencing to be OXA-2.  (+info)

Activities of beta-lactams and macrolides against Helicobacter pylori. (6/1422)

A continuous-culture system (chemostat) was used to study the activities of beta-lactam antimicrobial agents, clarithromycin, and 14-OH-clarithromycin against slowly growing Helicobacter pylori NCTC 11637. H. pylori was grown to steady state before exposure to these antimicrobial agents at x8 the MIC. The bactericidal actions of combinations of amoxicillin and clarithromycin were also studied. Viable counts (numbers of CFU per milliliter) were determined at 2-h intervals for 12 h and at 20 h after the addition of antibiotics. The effects of pH changes (6.5 to 7.4) on the activities of amoxicillin, clarithromycin, and the combination of these against H. pylori NCTC 11637 were also studied. Viable counts following exposure to ampicillin, cefixime, ceftazidime, cefuroxime, cefotaxime, azlocillin, and piperacillin at 20 h showed bacteriostatic activity. Imipenem, meropenem, amoxicillin, clarithromycin, and 14-OH-clarithromycin reduced the viable counts by 3 log10 CFU/ml (>/=99.9% killing). Imipenem was the most rapidly bactericidal against H. pylori NCTC 11637. Results of the pH experiments showed that amoxicillin was bactericidal at pHs 6.5 to 7. 4. Clarithromycin was bactericidal at pH 7.0 to 7.4 but was bacteriostatic at pH 6.5. The combination of amoxicillin and clarithromycin was bactericidal at pHs 6.5 and 7.0. A batch culture (flask system) was also used to investigate 12 strains of H. pylori for their susceptibilities to beta-lactams, clarithromycin, and/or 14-OH-clarithromycin in order to determine whether results from the chemostat model can be reproduced with batch cultures. Results of the chemostat time-kill kinetic study were reproducible in our batch culture flask system. The role of carbapenems in the eradication of H. pylori should be investigated.  (+info)

In vivo efficacies of combinations of beta-lactams, beta-lactamase inhibitors, and rifampin against Acinetobacter baumannii in a mouse pneumonia model. (7/1422)

The effects of various regimens containing combinations of beta-lactams, beta-lactam inhibitor(s), and rifampin were assessed in a recently described mouse model of Acinetobacter baumannii pneumonia (M. L. Joly-Guillou, M. Wolff, J. J. Pocidalo, F. Walker, and C. Carbon, Antimicrob. Agents Chemother. 41:345-351, 1997). Two aspects of the therapeutic response were studied: the kinetics of the bactericidal effect (treatment was initiated 3 h after intratracheal inoculation, and bacterial counts were determined over a 24-h period) and survival (treatment was initiated 8 h after inoculation, and the cumulative mortality rate was assessed on day 5). Two clinical strains were used: a cephalosporinase-producing strain (SAN-94040) and a multiresistant strain (RCH-69). For SAN-94040 and RCH-69, MICs and MBCs (milligrams per liter) were as follows: ticarcillin, 32, 64, 256, and >256, respectively; ticarcillin-clavulanate, 32, 64, and 512, and >512, respectively; imipenem, 0.5, 0.5, 8, and 32, respectively; sulbactam, 0.5, 0.5, 8, and 8, respectively; and rifampin, 8, 8, 4, and 4, respectively. Against SAN-94040, four regimens, i.e., imipenem, sulbactam, imipenem-rifampin, and ticarcillin-clavulanate (at a 25/1 ratio)-sulbactam produced a true bactericidal effect (>/=3-log10 reduction of CFU/g of lung). The best survival rate (i.e., 93%) was obtained with the combination of ticarcillin-clavulanate-sulbactam, and regimens containing rifampin provided a survival rate of >/=65%. Against RCH-69, only regimens containing rifampin and the combination of imipenem-sulbactam had a true bactericidal effect. The best survival rates (>/=80%) were obtained with regimens containing rifampin and sulbactam. These results suggest that nonclassical combinations of beta-lactams, beta-lactamase inhibitors, and rifampin should be considered for the treatment of nosocomial pneumonia due to A. baumannii.  (+info)

Inhibition of beta-lactamase in Neisseria gonorrhoeae by sodium clavulanate. (8/1422)

Sodium clavulanate at subinhibitory concentrations affected the activity of penicillin G, ampicillin, or amoxicillin on beta-lactamase-positive strains of Neisseria gonorrhoeae as demonstrated by marked reduction in the minimal inhibitory concentrations of the drugs for the organisms. The compound did not affect the activity of these penicillins on beta-lactamase-negative strains of N. gonorrhoeae. It also had no effect on the activity of cefoxitin against either beta-lactamase-negative or -positive strains. The reduction in minimal inhibitory concentrations of the penicillins for the beta-lactamase-positive organisms brought about by sodium clavulanate is probably due to inhibition of the beta-lactamase by the compound.  (+info)

  • The study will recruit potential subjects from children who are diagnosed with CAP and who are initiated on oral beta-lactam therapy by healthcare providers in EDs, outpatient clinics, and urgent care centers at the study sites. (
  • pH Dependence of and kinetic solvent isotope effects on the methanolysis and hydrolysis of .beta. (
  • The hydrolysis of cefoxitin, cephaloridine and benzylpenicillin catalysed by CoBcII (cobalt-substituted beta-lactamase from Bacillus cereus) has been studied at different pHs and metal-ion concentrations. (
  • Hydrolysis of the β-lactam ring by bacterial β-lactamases yields penicilloic acid, which lacks antibacterial activity. (
  • In other words, a pH value lower than 6.5 might also promote the hydrolysis action against β-lactams. (
  • The slow or nonenzymically mediated breakdown of imipenem and other broad-spectrum beta-lactams suggested the resistance of P. aeruginosa isolate to these drugs which may be attributed to both permeability and efflux. (
  • This dosing approach was applied to several beta-lactams commonly utilized in children. (
  • We have also addressed the synergistic interaction of rifampicin and several beta-lactams from a molecular perspective and have identified underlying molecular determinants explaining this interaction, something never reported to date. (
  • The first synthetic β-lactam was prepared by Hermann Staudinger in 1907 by reaction of the Schiff base of aniline and benzaldehyde with diphenylketene in a [2+cycloaddition (Ph indicates a phenyl functional group): Up to 1970, most β-lactam research was concerned with the penicillin and cephalosporin groups, but since then, a wide variety of structures have been described. (
  • 10. The method of claim 1, wherein the beta-lactam compound is a cephalosporin. (
  • 6 Of the three pharmacodynamic parameters described with antimicrobials, optimal efficacy with beta-lactams is achieved when free drug concentrations stay above the minimum inhibitory concentration (MIC) for an extended duration of the recommended dosing interval ( FIGURE 1 ). (
  • To determine the safety and efficacy of a new preventive agent for antibiotic-associated diarrhea (AAD) in patients receiving at least one beta-lactam antibiotic. (
  • The critical pharmacodynamic parameter for antibacterial efficacy of β -lactam antibiotics is the proportion of the dosing interval for which the serum concentration of the non-protein-bound fraction of the antibiotic remains above its minimal inhibitory concentration (MIC) vis à vis the targeted pathogen. (
  • To this day, the pharmacology of beta-lactam antibiotics has clearly bore out an excellent safety and efficacy profile. (
  • Detects more beta-lactam and tetracycline residues including cephalexin at or below established maximum residue limits. (
  • The SNAP Beta-Lactam ST Plus Test and the SNAPduo ST Plus Test contain a proprietary reformulated conjugate pellet that accurately and reliably detects beta-lactam and tetracycline antibiotic residues including cephalexin without heat or incubation, allowing you to test cold milk directly from the truck, refrigerator or bulk tank. (
  • In just 3 minutes, the Charm MRLBL3 Beta-lactam Test can detect the presence of 13 primary beta-lactam drugs in milk at or below EU and CODEX maximum residue limits. (