Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q29983 (MIC)
 21,138 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have conducted pharmacokinetic and clinical trials of a new cephem derivative, cefodizime (THR-221, CDZM), and obtained the following results. 1. We administered CDZM to 4 cases with abdominal simple hysterectomy due to myoma uteri at a dose level of 1 g by drip intravenous injection and studied average levels of transfer measured at various locations in the uterine tissues and adnexa at an average of 2 hours after administration. CDZM level was highest in the oviduct, 13.7 micrograms/g (ratio with respect to the uterine arterial blood: 91.3%), followed by the ovary, portio vaginalis, cervix uteri and endometrium, and was lowest in the myometrium, 8.3 micrograms/g (55.3%). CDZM concentrations were higher than 6.04 micrograms/g in any tissues. 2. To study CDZM transfer to pelvic cavity fluid, we administered CDZM to 5 cases with total hysterectomy due to cervical cancer of uteri at a dose level of 2 g using drip intravenous injection. The drug was transferred at high levels to the pelvic cavity fluid. A level of 11.7 micrograms/ml was observed at 3 hours after injection. The drug levels in the pelvic cavity fluid were maintained continuously higher levels than those of venous blood. These concentrations in the uterine tissues and pelvic cavity fluid were higher than the MIC against many strains of Gram-positive and Gram-negative bacteria, hence we considered them to be therapeutically effective concentrations. 3. Eleven cases of gynecological infections receiving in totals of 8 to 48 g of CDZM demonstrated "excellent" results in 3 cases, "good" in 8 cases. Eight strains of organisms were isolated from 10 cases.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Pharmacokinetic and clinical studies on cefodizime in the field of obstetrics and gynecology]. 260 3

Cefodizime (THR-221, CDZM), a new cephalosporin antibiotic, was evaluated for its safety and efficacy in 27 children with various bacterial infections. The episodes of infections included pneumonia (6 cases), bronchopneumonia (11 cases), lung abscess (1 case), acute pharyngitis (2 cases), cervical lymphadenitis (1 case), infected cephalohematoma (1 case), urinary tract infection (1 case), sepsis (2 cases) and purulent meningitis (2 cases). CDZM was effective in all but one, and its efficacy rate was 96.3%. The main etiologic pathogens were Staphylococcus aureus, Haemophilus influenzae, Haemophilus parainfluenzae, Streptococcus pneumoniae, Streptococcus agalactiae, Escherichia coli, Citrobacter freundii and Branhamella catarrhalis. The elimination rate was 92.3%. As adverse reactions or abnormalities, diarrhea was encountered in 4 cases. A slight elevation of serum transaminases or eosinophils was observed in 4 cases. The serum half-life was approximately 1.8-1.9 hours in children after intravenous bolus injections. Concentrations of CDZM in cerebrospinal fluids were well above MIC values of CDZM against those organisms responsible for the infections. The data suggest that CDZM is a safe and effective antibiotic when used in children with bacterial infections including purulent meningitis.
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PMID:[Clinical and pharmacokinetic study on cefodizime, a new cephalosporin antibiotic, in the pediatric infections]. 279 54

Cefodizime (THR-221, CDZM), a new parenteral cephalosporin, was evaluated for its efficacy and safety in 20 children with bacterial infections (Table 1), and the following results were obtained. 1. CDZM was administered in 3 or 4 divided doses at daily dosages ranging from 54.5 to 84.2 mg/kg administered by 30 minutes drip infusion or intravenous injection to 20 patients (7 cases of acute tonsillitis, 6 cases of pneumonia, 2 cases each of bronchitis and suppurative cervical lymphadenitis, and 1 case each of acute pharyngitis, acute enteritis and furunculosis) and the following clinical results were obtained: excellent, 7 cases; good, 11 cases; fair, 2 cases. The overall efficacy rate was 90% (Table 4). 2. MICs of CDZM against 15 strains of isolated organisms are shown in Table 2. MICs against all 7 strains of Haemophilus influenzae were less than 0.025 micrograms/ml. MIC against 1 out of 5 strains of Streptococcus pneumoniae was 0.05 micrograms/ml and those against 2 strains were 0.10 micrograms/ml and against the other 2 were 0.20 micrograms/ml. MICs against 3 strains of Staphylococcus aureus were 1.56, 25 and higher than 100 micrograms/ml, respectively. 3. No clinical adverse reaction was observed in any of the 20 patients. Eosinophilia was observed in 2 cases. A slight elevation of S-GOT was found in 1 patient (case No. 8) and moderate elevation of S-GOT and S-GPT in another (case No. 18) (Table 4). In case No. 18, the S-GOT and S-GPT activity improved after the administration of the drug was stopped.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Clinical evaluation of cefodizime in children]. 279 59

Cefodizime (CDZM, THR-221), a new cephem antibiotic, was investigated for its clinical efficacy and pharmacokinetics in children. The results obtained are summarized as follows. 1. Antimicrobial activities Antimicrobial activities of CDZM against clinically isolated organisms were determined. MICs of CDZM against 1 strain each of Streptococcus pneumoniae, Escherichia coli and Klebsiella pneumoniae were 0.05 micrograms/ml to 0.10 micrograms/ml. Especially, MIC against all 6 strains of Haemophilus influenzae was less than or equal to 0.024 micrograms/ml. This MIC value was lower than those of other antibiotics such as cefotaxime, cefotiam, cefazolin, piperacillin. 2. Pharmacokinetics CDZM was given to 1 case at a dose of 20 mg/kg by a 60-minute intravenous drip infusion. The peak value of serum concentration of CDZM was 207.80 micrograms/ml at the end of the infusion. The half-life was 2.15 hours. The mean urinary excretion rate was 68.5% in the first 4 hours, 79.2% in 6 hours and 76.5% in 8 hours after the 30-minute drip infusion. 3. Clinical efficacy CDZM was given to a total of 27 patients, 13 with pneumonia, 1 with bronchitis, 2 with acute pharyngitis, 1 with purulent tonsillitis, 5 with urinary tract infection, 1 each with retrograde cholangitis, acute enteritis, pericementitis, phlegmon and inguinal lymphadenitis. Overall clinical efficacies were excellent in 5 cases, good in 17 and the efficacy rate was 81%. Bacteriological effects were investigated in 13 cases and the eradication rate was 85%. No adverse reactions were observed in any case. As abnormal laboratory findings, elevated GOT, GPT, A1-P, LAP and gamma-GTP, were noted in 1 out of the 28 cases examined.
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PMID:[Clinical and pharmacokinetic evaluation of cefodizime in children]. 279 60

Clinical studies were performed on cefodizime (THR-221, CDZM), a new cephem antibiotic as described below. CDZM was administered to 13 patients in dose levels ranging from 55 to 96 mg/kg/day t.i.d. for 3-7 days (5.5 days on average). These patients included 8 with pneumonia, 2 with tonsillitis, 1 each with bronchitis, phlegmon and urinary tract infection. The overall efficacy rate was 92.3%, i.e., efficacy was excellent in 8, good in 4 and poor in 1. Bacteriological efficacy was 83.3%, i.e., 5 strains of bacteria (Streptococcus pneumoniae 1, Haemophilus influenzae 3, Haemophilus parainfluenzae 1) were eradicated and 1 was unchanged (Enterobacter cloacae, MIC greater than 100 micrograms/ml). Clinical side effect was not observed during the treatment. Laboratory abnormalities were observed in 2 cases, i.e., a slight elevation of GPT and a mild eosinophilia. The above results suggest that CDZM is a useful antibiotic for treating pediatric bacterial infections.
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PMID:[Clinical experience with cefodizime in bacterial infection of children]. 279 62

Among its penicillin-binding proteins (PBPs), Enterococcus faecium possesses a low-affinity PBP5, PBP5fm, which is the main target involved in beta-lactam resistance. A 7.7-kb EcoRI chromosomal fragment of E. faecium D63r containing the pbp5fm gene was cloned and sequenced. Two open reading frames (ORFs) were found. A 2,037-bp ORF encoded the deduced 73.8-kDa PBP5fm, the amino acid sequences of which were, respectively, 99.8, 78.5, and 62% homologous to those of the low-affinity plasmid-encoded PBP3r of Enterococcus hirae S185r and the chromosome-encoded PBP5 of E. hirae R40 and Enterococcus faecalis 56R. A second 597-bp ORF, designated psrfm, was found 2.3 kb upstream of pbp5fm. It appeared to be 285 bp shorter than and 74% homologous with the regulatory gene psr of E. hirae ATCC 9790. Different clinical isolates of E. faecium, for which a wide range of benzylpenicillin MICs were observed, showed that the increases in MICs were related to two mechanisms. For some strains of intermediate resistance (MICs of 16 to 64 micrograms/ml), the increased level of resistance could be explained by the presence of larger quantities of PBP5fm which had an affinity for benzylpenicillin (second-order rate constant of protein acylation [k+2/K] values of 17 to 25 M(-1) s(-1)) that remained unchanged. For the two most highly resistant strains, EFM-1 (MIC, 90 micrograms/ml) and H80721 (MIC, 512 micrograms/ml), the resistance was related to different amino acid substitutions yielding very-low-affinity PBP5fm variants (k+2/K < or = 1.5 M(-1) s(-1)) which were synthesized in small quantities. More specifically, it appeared, with a three-dimensional model of the C-terminal domain of PBP5fm, that the substitutions of Met-485, located in the third position after the conserved SDN triad, by Thr in EFM-1 and by Ala in H80721 were the most likely cause of the decreasing affinity of PBP5fm observed in these strains.
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PMID:Structure of the low-affinity penicillin-binding protein 5 PBP5fm in wild-type and highly penicillin-resistant strains of Enterococcus faecium. 875 60

Many oral penicillins and cephalosporins are used to treat clinical infections caused by Streptococcus pneumoniae. Therefore, using different beta-lactams as selectors, we estimated the frequencies of one-step mutations leading to resistance. Resistant mutants were obtained from penicillin-susceptible, intermediately resistant, and penicillin resistant strains. For cefixime, cefuroxime, cefpodoxime, cefotaxime, and ceftriaxone, the frequencies of mutation ranged from 10(-6) to 10(-8) when resistant mutants were selected at 2- to 8-fold the MIC, and the MICs increased 2- to 16-fold. For ampicillin, ampicillin-sulbactam, amoxicillin, amoxicillin-clavulanic acid, cefaclor, and loracarbef, the frequencies of mutation were about 10(-7) to 10(-8), and the MICs increased twofold at most. One to three resistance profiles of the resulting mutants were selected for each of the selecting antibiotics. Among those, some showed resistance to the cephalosporins associated with a 2- to 32-fold increase in susceptibility to the penicillins. Competition experiments showed a decreased affinity of PBP2x for cefpodoxime in all mutants. In some mutants that were more susceptible to amoxicillin, a decreased affinity of PBP2x for cefpodoxime was associated with an increased affinity for amoxicillin and a particular substitution of alanine for threonine at position 550 just after the KSG triad. From these results we infer (i) that among the beta-lactams tested the penicillins, cefaclor, and loracarbef selected one-step resistant mutants less frequently and that they achieved a lower level of resistance, and (ii) that mutants with different profiles may have acquired different point mutations in PBP2x.
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PMID:In vitro selection of one-step mutants of Streptococcus pneumoniae resistant to different oral beta-lactam antibiotics is associated with alterations of PBP2x. 878 97

A clinical isolate of Pseudomonas aeruginosa G48, became resistant during fluoroquinolone treatment giving rise to the post-therapy isolate, G49. To determine whether mutation in gyrA gave rise to fluoroquinolone resistance, G49 was transformed with a plasmid encoding gyrA (pNJR3-2); this reduced the MIC of fluoroquinolones for G49 two-fold. DNA sequencing of gyrA of G49 demonstrated a mutation at Thr-83, substituting with isoleucine. The outer membrane of G49 was shown to lack OprF, suggesting that loss of this protein may be involved in the multiple antibiotic resistance phenotype; however, when G49 was transformed with a plasmid encoding oprF (pRW5), expression of oprF was shown to have no effect upon the phenotype.
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PMID:Role of gyrA mutation and loss of OprF in the multiple antibiotic resistance phenotype of Pseudomonas aeruginosa G49. 880 97

High-level resistance to beta-lactam antibiotics in Streptococcus pneumoniae is mediated by successive alterations in essential penicillin-binding proteins (PBPs). In the present work, single amino acid changes in S. pneumoniae PBP 2x and PBP 2b that result in reduced affinity for the antibiotic and that confer first-level beta-lactam resistance are defined. Point mutations in the PBP genes were generated by PCR-derived mutagenesis. Those conferring maximal resistance to either cefotaxime (pbp2x) or piperacillin (pbp2b) were obtained after transformation of the susceptible laboratory strain R6 with the PCR-amplified PBP genes and selection on agar with various concentrations of the antibiotic. In the case of PBP 2x, transformants for which the cefotaxime MIC was 0.16 microgram/ml contained the substitution of a Thr for an Ala at position 550 (Thr550-->Ala), close to the PBP homology box Lys547SerGly, a mutation frequently observed in laboratory mutants and in a high-level cefotaxime-resistant clinical isolate as well. After further selection, transformants resisting 0.3 microgram of cefotaxime per ml were obtained; they contained the substitution Gly550 as the result of two mutations in the same codon. In PBP 2b, Thr446-->Ala, adjacent to another homology box Ser443SerAsn, was the mutation selected with piperacillin. This substitution has been described in all clinical isolates with a low-affinity PBP 2b but was distinct from point mutations found in laboratory mutants. Both pbp2b with the single mutation and a mosaic pbp2b of a clinical isolate conferred a twofold increase in piperacillin resistance. Attempts to select PBP 2b variants at higher piperacillin concentrations were unsuccessful. The mutated PBP 2b also markedly reduced the lytic response to piperacillin, suggesting that such a mutation is an important step in resistance development in clinical isolates.
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PMID:Penicillin-binding proteins 2b and 2x of Streptococcus pneumoniae are primary resistance determinants for different classes of beta-lactam antibiotics. 884 35

Proteus vulgaris and RTEM-1 beta-lactamases that belong to molecular class A with 37% amino acid similarity were examined to find the relationship between amino acid residues and activity of enzymes. MICs of ampicillin were > 2,000 micrograms/ml for Escherichia coli cells producing these enzymes. We have made 18 hybrid genes by substituting the coding region of the P. vulgaris beta-lactamase gene with the equivalent portions from the RTEM-1 gene. Most of these hybrids produced inactive proteins, but a few hybrid enzymes had partial or trace activity. From one of the hybrid genes (MIC of ampicillin, 100 micrograms/ml), we recovered three kinds of active mutants which provided ampicillin MICs of 1,000 micrograms/ml by the selection of spontaneous mutations in a dnaQ strain of E. coli. In these mutants, Leu-148, Met-182, and Tyr-274 were replaced with Val, Thr, and His, respectively. These amino acids have not been identified as residues with functional roles in substrate hydrolysis. Furthermore, from these hybrid mutants, we obtained a second set of mutants which conferred ampicillin MICs of 1,500 micrograms/ml. Interestingly, the second mutations were limited to these three amino acid substitutions. These amino acid residues which do not directly interact with substrates have an effect on enzyme activity. These mutant enzymes exhibited lower K(m) values for cephaloridine than both parental enzymes.
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PMID:Recovery of active beta-lactamases from Proteus vulgaris and RTEM-1 hybrid by random mutagenesis by using a dnaQ strain of Escherichia coli. 887 98


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