• YAKHAK HOEJI
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• v.39 no.3
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• pp.276-282
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• 1995

Compared to the first and second-generation cephalosporins, the third-generation cephalosporins are remarkably stable against hydrolysis by the $\beta$-lactamases produced by aerobic gram-negative bacilli, such as Enterobacteriaceae. Among these bacteria, the most prevalent plasmid-encoded $\beta$-lactamase is TEM-1 $\beta$-lactamase belonging to class A or group 2b. This enzyme is produced constitutively and is principally active against peniciflins and old cephalosporins rather than third-generafion cephalosporins, carbapenems and mmobactams. However, new TEM type $\beta$-lactamases including TEM-9 and TEM-12 evolved through point mutations in a gene encoding $\beta$-lactamase have been discovered from patients during chemotherapy. These $\beta$-lactamases are known to be capable of hydrolyzing most of the third-generatim cephalosporins. To study the prevalence of $\beta$-lactamases from clinical isolates collected in Korea. the minimal inhibitory concentratims(MICs) of several third-generation cephalosporins against 628 clinical isolates were determined by agar dilution methods, and $\beta$-lactamas-producing bacteria were isolated by use of cefinase disc. By polymerase chain reaction (PCR) method, clinical isolates harboring a gene for TEM type $\beta$-lactamase were identified among the $\beta$-lactamase producing strains. Twentiy three percent of the clinical isolates was resistant to the thirdgeneration cephalosporins, and more than 90% of resistant cells produced various $\beta$-lactamases. TFM type $\beta$-lactamases were dominant in gram-negative bacilli, such as Escherichia coli, Klebsiella pneumoniae, Enterobacter species. These results suggest the necessity of the development of new cephalosporins which are stable against $\beta$-lactamases like TEM.

• Korean Journal of Clinical Laboratory Science
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• v.46 no.1
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• pp.22-30
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• 2014

Research on the correlation between blood glucose and allergy of the trauma patient, and the changes of blood glucose after the injection of antibiotic Cephalosporins have been made in this study. In this research, we have investigated whether there is any correlation between allergies and blood glucose, and the changes of blood glucose after the injection of Cephalosporins. In case of the patients who have allergies, there has been a close correlationship between allergies and blood glucose by increasing the risk of developing sugar diabetes significantly to 3.273. And it showed that there is a correlation between Cephalosporins and glucose by the figure of Cephalosporins, before and one week after the operation, to become r=1**.*, bilateral significance probability (p<0.007). There has been significant changes in blood glucose (p<0.010), bun (p<0.025), Albumin (p<0.000), AST (p<0.001), total bilirubin (p<0.001) after the operation. It considered to be important indicator. preventing complications and allergies caused by diabetic history and also correlated (p<0.027) because there is allergy and the patient's.

• Archives of Pharmacal Research
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• v.14 no.3
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• pp.279-281
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• 1991

In the field of cephalosporins, introduction of quaternary heterocyclic methyl goups at the C-3 position has led to a new class of cephalosporins such as cefepime and cefpirome, the so-called 4th generation cephalosporins which are characterized by their potent activity. Since than many efforts were attempted to synthesize more effective analogs.

• Bulletin of the Korean Chemical Society
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• v.11 no.6
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• pp.538-542
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• 1990

New aminothiazolyl cephalosporins with alkoxyiminomethyl(2-aminothiazol-4-yl)acetyl substituents at 7-position of cephems were synthesized starting from (2-aminothiazol-4-yl)acetate via one carbon homologation followed by acylation with 7-aminoceph-3-em-4-carboxylic acid derivatives. These new aminothiazolyl cephalosporins exhibit promising in vitro activities against various strains including Gram positive bacteria.

• Archives of Pharmacal Research
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• v.7 no.1
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• pp.11-15
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• 1984

Binding of sic cephalosporins (cefotaxime, cefuroxime, cafazoline, cephalothin, cephaloridine, cephacetrile) to human serum albumin was studied. Fluorescence probe technique and difference spectrophotometry were employed to evaluate the nature and degree of association of cephalosporin-albumin complex. 1-anilinonaphthalene-8-surfonate was used as the fluorescence probe, and 2-(4'-hydroxybenzeneazo)benzoic acid as the UV spectrophotometric probe. Competitive bindings between cephalosporins and probe were observed. For the binding of cephalosporins to human serum albumin, three binding sites were identified by fluorescence probe technique but four binding constants of cephalosporins to human serum albumin measured by fluorescence probe technique are higher than those meausred by UV spectrophotometry.

• YAKHAK HOEJI
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• v.32 no.3
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• pp.182-186
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• 1988

Binding of four cephalosporins(cefaclor, cefpiramide, ceftazidime, ceforanide) to bovine serum albumin was studied. Difference spectrophotometry was employed to evaluate the nature and the degree of association of cephalosporin-albumin complex. 2-(4'-hydroxybenzen azo) benzoic acid was used as the uv spectrophotometric probe for measuring the binding of cephalosporins to bovine serum albumin. Competitive bindings between cephalosporins and probe were observed. For the binding of cephalosporins to bovine serum albumin, three binding sites were identified. The binding constants of cefaclor, ceforanide, ceftazidime and cefpiramide were $12.57\;{\times}\;10^{-2}M^{-1}$, $6.49\;{\times}\;10^{-2}M^{-1}$, $4.70\;{\times}\;10^{-2}M^{-1}$ and $6.20\;{\times}\;10^{-2}M^{-1}$ respectively.

• Journal of Veterinary Science
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• v.25 no.3
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• pp.47.1-47.12
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• 2024

Importance: Staphylococcus aureus and Escherichia coli contribute to global health challenges by forming biofilms, a key virulence element implicated in the pathogenesis of several infections. Objective: The study examined the efficacy of various generations of cephalosporins against biofilms developed by pathogenic S. aureus and E. coli. Methods: The development of biofilms by both bacteria was assessed using petri-plate and microplate methods. Biofilm hydrolysis and inhibition were tested using first to fourth generations of cephalosporins, and the effects were analyzed by crystal violet staining and phase contrast microscopy. Results: Both bacterial strains exhibited well-developed biofilms in petri-plate and microplate assays. Cefradine (first generation) showed 76.78% hydrolysis of S. aureus biofilm, while significant hydrolysis (59.86%) of E. coli biofilm was observed by cefipime (fourth generation). Similarly, cefuroxime, cefadroxil, cefepime, and cefradine caused 78.8%, 71.63%, 70.63%, and 70.51% inhibition of the S. aureus biofilms, respectively. In the case of E. coli, maximum biofilm inhibition (66.47%) was again shown by cefepime. All generations of cephalosporins were more effective against S. aureus than E. coli, which was confirmed by phase contrast microscopy. Conclusions and Relevance: Cephalosporins exhibit dual capabilities of hydrolyzing and inhibiting S. aureus and E. coli biofilms. First-generation cephalosporins exhibited the highest inhibitory activity against S. aureus, while the third and fourth generations significantly inhibited E. coli biofilms. This study highlights the importance of tailored antibiotic strategies based on the biofilm characteristics of specific bacterial strains.

• YAKHAK HOEJI
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• v.37 no.3
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• pp.295-305
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• 1993

In order to develop oral cephalosporin having a new substituent at 3 position, the synthesis of cephalosporins modified at C-3 and the effect of the substituents on the oral absorption is studied. 7-[(Z)-2-(2-Aminothiazole- 4-yl)-2-methoxyiminoacetamidol-3-[4-(2-pyridyl )piperazinyl] thiocarbonylthiomethyl-3-cephem-4-carboxylic acid (CEN1) and 7-[(Z)-2-(2-aminothiazole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyrimid yl)piperazinylthiocarbonylthiomethyl-3-cephem-4-carboxylic acid (CEN2) were synthesized from 4-(2-piridyl)piperazinyl dithiocarbamate potassium salt or 4-(2-pirimidyl)piperazinyl dithiocarbamate potassium salt and cefotaxime. Also pivaloyloxymethyl esters of CEN1 and CEN2, pivaloyloxymethyl 7-[(Z)-2-(2-aminothiazole-4-yl)-2-methoxyiminoacetamido]-3-[4-(2-pyridyl )piperazinyllthiocarbonylthiomethyl-3-cephem-4-carboxylate (CENIP) and pivaloyloxymethyl 7-[(Z)-2-(2-aminothiazole-4-yl)-2-methoxyiminoacetamidol-3- [4-(2-pyrimid yl)piperazinyllthiocarbonylthiomethyl-3-cephem-4-carboxylate (CEN2P) were synthesized. The in vitro activities of two new oral cephalosporins, CEN1 and CEN2, were compared with the in vitro activities of cefaclor and cefotaxime against a variety of bacterial species. CEN2 has a broad antibacterial spectrum covering Gram-positive and Gram-negative bacteria, similar to that exhibited by CEN1 and cefotaxime. CEN1 and CEN2 were more active in vitro than cefaclor against Streptococcus pyogenes, Klebsiella aerogenes and Enterobacter cloacae.

• Korean Journal of Veterinary Service
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• v.38 no.4
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• pp.259-264
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• 2015

We investigated the residues of 6 cephalosporins (cefquinome, cephalexin, cephalonium, cefazolin, ceftiofur, cefuroxime) using LC-MS/MS in raw meat in Seoul. This method involves extraction of the residue from the meat by distilled water and methanol followed by a manual of residue analysis published by the National Institute of Food and Drug Safety Evaluation. The recoveries ranged between 74.71~90.01% in beef, 73.37~101.40% in pork and 70.87~95.53% in chicken, respectively. The limits of detection were 0.0004~0.0563 mg/kg, and the limits of quantification were 0.001~0.169 mg/kg respectively. Residues of cephalosporins which exceeded maximum residue limits (MRL) were not exceed in any of the 287 samples. However, it is necessary to develop multi-method, which includes the active metabolites of ceftiofur.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1669-1670
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• 2005