Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026936 (Mycoplasma)
 14,761 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The authors have carried out laboratory and clinical studies of 9,3"-diacetylmidecamycin (MOM) and obtained the following results. 1. Absorption and excretion of MOM. MOM was administered orally to 4 patients at a dose of 10 mg/kg in the fasting condition. The peak of serum levels was found at 30 minutes after administration. The mean values were 1.3 +/- 0.5 microgram/ml, and 1.1 +/- 0.9 microgram/ml after 30 minutes and 1 hour respectively. The serum levels were detectable in 2 cases after 2 hours (1.0 and 0.78 microgram/ml), in 1 case after 4 hours (0.78 microgram/ml) and were not detectable in all cases after 6 hours. Half-life was able to calculate in 2 cases (2.5 and 1.5 hours). The mean urinary recovery rate examined in 3 cases was 0.33% for initial 6 hours. 2. Clinical result. MOM was administered to 35 children at a daily dose of 16.7--51.1 mg/kg divided into 3 or 4 doses for 4 to 19 days: 18 cases with bacterial infection (9 cases with tonsillitis, 7 cases with scarlet fever and each 1 case with bronchitis and pneumonia) and 17 cases with Mycoplasma infection (5 cases with bronchitis and 12 cases with pneumonia). The overall clinical response was good in 28 cases (80.0%), fair in 6 cases and poor in 1 case. The efficacy rate in bacterial infections and Mycoplasma infections were 66.7 and 94.1% respectively. Eight strains of S. pyogenes and 1 strain of S. pneumoniae were isolated from 9 cases. One strain of S. pyrogenes was eradicated and the others were unchanged. The eradication rate was 11.1%. The MIC of MOM against S. pyogenes was above 50 micrograms/ml in 3 strains out of measured 5 isolated strains. 3. Side effect. Side effects were examined with all the 54 cases involving 19 drop-out cases. Although clinical side effects were not observed, a mild elevation in GOT and a mild rise in eosinophil were observed in 2 cases and 1 case respectively.
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PMID:[Laboratory and clinical studies of 9,3"-diacetylmidecamycin in the pediatric field]. 698 50

The 4"-O-substituted tylosin derivatives were prepared by selective esterification of the 4"-OH, and relationships between the substituent groups and antimicrobial activity against macrolide-resistant strains were examined. Introduction of branched-chain aliphatic acyl groups such as 2-methoxyisovaleryl or 4-methylvaleryl group afforded derivatives with good antibacterial activity; MIC values were 12.5 microgram/ml against Staphylococcus aureus MS-8710. MIC values of tylosin, erythromycin and josamycin against this strain were 800 microgram/ml or more. Further improved activity was obtained by introduction of aromatic groups such as phenylthioacetyl, phenylsulfonylacetyl, 4-nitrophenylacetyl, 4-nitrophenylsulfonyl and phenylethanesulfonyl groups; MIC values were 6.25 microgram/ml. These derivatives had also an improved antimycoplasmal activity; MIC values were 0.08 microgram/ml against macrolide-resistant strains of Mycoplasma gallisepticum. MIC values of tylosin against these strains were from 2.5 to 10 microgram/ml. Introduction of the groups described above into the 4"-OH was confirmed to increase the uptake by a resistant strain.
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PMID:Studies of tylosin derivatives effective against macrolide-resistant strains: synthesis and structure-activity relationships. 711 22

Macrolide and tetracycline antibiotics, which are protein synthesis inhibitors, are effective in the treatment of mycoplasma pneumonia. We evaluated the clinical efficacy and safety of roxithromycin, a new macrolide antibiotic, in the treatment of mycoplasma pneumonia. Roxithromycin was administered orally to patients who had been definitely diagnosed through Mycoplasma pneumoniae isolation or serum antibody titer as having mycoplasma pneumonia. The efficacy assessment was based on clinical signs and symptoms of infection as well as bacterial culture from clinical samples. Clinical efficacy was excellent in 6 cases, good in 6 cases and fair in 1 case, with an efficacy rate of 92.3%. The bacteriological effect was evaluated in 6 patients: the organism was eradicated in 4 cases and unchanged in 2 cases. In this study, the MIC of roxithromycin against M. pneumoniae fell in the range 0.0156-0.00625 mg/l. No adverse reaction was observed. As for abnormal laboratory findings, two cases showed elevated serum glutamic-pyruvic transaminase (S-GPT), one elevated serum glutamic-oxaloacetic transaminase and S-GPT, and one reduced neutrophil counts. From our results, we consider that roxithromycin is useful in the treatment of mycoplasma pneumonia.
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PMID:Efficacy of roxithromycin in the treatment of mycoplasma pneumonia. 775 59

Mycoplasma fermentans strains reputedly from human infections or tissue culture cells were much more susceptible to azithromycin than to clarithromycin or erythromycin. Lincomycin, clindamycin and several tetracyclines also exhibited good mycoplasmastatic activity but mycoplasmacidal concentrations were substantially greater than the MICs. Ciprofloxacin was the most active of three fluoroquinolones tested and was mycoplasmacidal at concentrations close to the MIC. Tiamulin and mupirocin were also very active. Synergy with specific M. fermentans antiserum plus guinea-pig complement was not observed with any class of antibiotic although the number of viable mycoplasmas was markedly reduced by the combined immunological components. Marked differences in susceptibility to various aminoglycosides were observed. Human strains isolated in cell-free media up to 1967 were aminoglycoside susceptible (MIC range 0.5-25 mg/L) but recent human isolates and strains isolated from tissue culture cells often showed either single or multiple aminoglycoside resistance (MIC > 500 mg/L). Two aminoglycoside-susceptible strains developed resistance to streptomycin or neomycin (> 500 mg/L) within five passages in broth containing streptomycin or neomycin, respectively. Resistance to tobramycin, kanamycin or gentamicin emerged after seven, eight and 14 cycles of exposure to the respective antibiotic. Streptomycin resistance was associated with a five-fold increase in resistance to tobramycin. Neomycin-, kanamycin-, gentamicin- and tobramycin-resistant variants showed mutual cross-resistance but remained susceptible to streptomycin. Induced resistance persisted for at least 17 passages in aminoglycoside-free broth. The use of aminoglycosides in human medicine and the frequent inclusion of some of these drugs in tissue cell cultures to combat bacterial and mycoplasmal contamination might account for the aminoglycoside resistance of recent M. fermentans isolates.
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PMID:Antibiotic susceptibility of Mycoplasma fermentans strains from various sources and the development of resistance to aminoglycosides in vitro. 779 Dec 7

The pattern of distribution of bacteria, Mycoplasma pneumoniae and virus isolated from the same specimen recovered from the throat swab or the sputum of 479 patients with respiratory infections who were seen in six private clinics in Sendai City of Japan during the period from October to November in 1992 (period I) and from January to February in 1993 (period II) was documented. Of the 479 patients, 234 had acute pharyngitis, 145 had acute bronchitis, 96 had influenza, 21 had acute tonsillitis, 5 had acute pneumonia and 9 had other respiratory infections. One hundred (42.4%) strains of potential pathogen and one strain of M. pneumoniae were recovered from 236 cases in period I, and 66 (27.2%) strains of potential pathogen, one strain of M. pneumonae and 73 strains of Influenza virus (30.0%: 43 of type A Hong-Kong and 30 of type B) from 243 cases in period II. Of the 166 strains, major isolates were Staphylococcus aureus (56 strains), Streptococcus pneumoniae (12 strains), Streptococcus pyogenes (15 strains), Haemophilus influenzae (17 strains), Esherichia coli (4 strains), Klebsiella spp. (35 strains), Pseudomonas aeruginosa (4 strains) and Acinetobacter spp. (23 strains). Only one strain of S. aureus was resistant to methicillin (MIC: 50 micrograms/ml). None of S. pneumoniae was resistant to 1 microgram/ml of ampicillin. Ciprofloxacin was administered to 113 cases and roxythromycin to 220 cases by doctors in charge.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Studies on respiratory infections in primary care clinic (V). The pattern of distribution on bacteria, Mycoplasma pneumoniae and virus isolated from patients with respiratory infections, who were seen in six private clinics, and clinical efficacy of ciprofloxacin and roxithromycin]. 782 4

Norfloxacin nicotinate (NFN) is a new water-soluble fluoroquinolone antibacterial agent. The in vitro activity of NFN for microorganisms isolated from swine and the pharmacokinetic properties of NFN following single intravenous (i.v.), intramuscular (i.m.) and subcutaneous (s.c.) administration were investigated. The minimal inhibitory concentrations (MIC's) of NFN for a wide range of reference (ATCC-American Type Culture Collection) microbial swine isolates, comprising 21 bacterial and 5 mycoplasmal species, ranged between 0.03 micrograms/ml (for Salmonella cholerasuis and Actinobacillus pleuropneumonia) and 12.5 micrograms/ml (for Streptococcus porcinus). The MIC of NFN for Mycoplasma hyopneumoniae, the causative agent of enzootic pneumonia of pigs, was < 1.0 microgram/ml although M. hyosynoviae was less sensitive, with a MIC value of 3.12 micrograms/ml. The MIC values of the drug for swine field isolates, comprising 8 bacterial species, were in good agreement with the values determined for the corresponding ATCC strains. Pharmacokinetic values for NFN were calculated following i. v. administration at 7.0 mg/kg and i. m. and s. c. administration at 14.0 mg/kg in a 3-way cross over study involving 6 pigs. Plasma concentrations of unchanged drug were determined by HPLC during 24 h post injection. Plasma NFN concentrations measured after i.v. dosing best fitted a 2-compartment open system pharmacokinetic model. The harmonic mean distribution half-life (t1/2 alpha) and elimination half-life (t1/2 beta) were 4.2 minutes and 2.1 h, respectively. The mean residence time (MRT) was 2.9 +/- 0.6 h and the steady state volume of distribution (Vss) was 3.2 +/- 0.1 l/kg. The mean t1/2 beta values after either i. m. or s. c. administration were 4.45 h with very rapid absorption rates (< 15 min to peak plasma drug concentration). Bioavailability was 51-64%. Less than 20% and 25% of the dose were excreted in the urine as parent drug during the first 24 h after i.v. and s.c. dosing, respectively whereas the amount of unchanged drug recovered in the feces was very small (1.3 to 1.6% of the dose). The pharmacokinetic and MIC data generated in the course of the present study suggest that a dose schedule of 14.0 mg/kg injected i. m. or s. c. every 24 h is capable of achieving and maintaining tissue drug concentrations of potential therapeutic value for the treatment of the most common bacterial and mycoplasmal infections in swine.
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PMID:Clinical pharmacokinetic characterization of norfloxacin nicotinate in swine following systemic administration. 794 48

Because mycoplasmas may be a cofactor in the progression of human immunodeficiency virus infection to AIDS, their susceptibilities to antibiotics need to be known in the event that appropriate therapy is required. The mycoplasmas studied were a stock culture strain of Mycoplasma fermentans, two strains of M. fermentans isolated from patients with AIDS, M. fermentans var. incognitus, Mycoplasma penetrans, and Mycoplasma pirum. The antibiotics tested were doxycycline, tetracycline, clindamycin, ofloxacin, erythromycin, azithromycin, and clarithromycin at levels consistent with the attainable levels in serum. By the macrodilution metabolic inhibition method, all six mycoplasma strains were susceptible to doxycycline, tetracycline, clindamycin, ofloxacin, azithromycin, and clarithromycin. M. penetrans was susceptible to erythromycin. The M. fermentans strains and M. pirum were resistant to erythromycin. The macrodilution metabolic inhibition method results showed agreement with the Sensititre Gram Positive MIC Panel results for tetracycline, clindamycin, and erythromycin. MICs of clarithromycin for all six mycoplasma isolates tested were low, indicating susceptibility.
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PMID:Antibiotic susceptibilities of AIDS-associated mycoplasmas. 802 22

We investigated the in vitro and in vivo activities of macrolides against Mycoplasma pneumoniae. In vitro MICs of azithromycin, erythromycin, clarithromycin, and roxithromycin were determined. Azithromycin was the most potent antimicrobial agent tested in vitro. Its MIC for 90% of the strains was 0.00024 micrograms/ml. MICs for 90% of the strains of erythromycin, clarithromycin, and roxithromycin were 0.0156, 0.0078, and 0.03125 micrograms/ml, respectively. In vivo activities were assessed in a pulmonary infection model with Syrian golden hamsters. We evaluated the in vivo effects on reduction of viable M. pneumoniae cell counts and on reduction of microscopic and macroscopic histopathologies for azithromycin, erythromycin, and clarithromycin given at 10 mg/kg once daily for 1 and 3 days and given at 15 mg/kg twice daily for 2.5 and 5 days. Azithromycin was significantly more effective than erythromycin or clarithromycin in the same regimens. Especially at 10 mg/kg once daily for 1 day, only azithromycin was significantly effective in the reduction of viable M. pneumoniae cells and histopathologies. These results show that azithromycin is more efficacious than the other drugs tested against M. pneumoniae pneumonia in hamsters. These data suggest that clinical studies of macrolides in human patients are warranted.
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PMID:In vitro and in vivo activities of macrolides against Mycoplasma pneumoniae. 803 Oct 48

The in vitro activities of two glycylcyclines, CL 329,998 and CL 331,002 (two new semisynthetic tetracyclines), were evaluated in comparison with those of tetracycline and other available oral antimicrobial agents. A total of 523 recent clinical isolates were studied, including strains resistant to tetracycline. Members of the family Enterobacteriaceae were generally > or = 16-fold more susceptible to the glycylcyclines than to tetracycline (although less difference was seen with Proteus spp.). Pseudomonas aeruginosa was modestly susceptible to both new compounds (MIC for 90% of strains tested [MIC90], 16 micrograms/ml). Tetracycline- and methicillin-susceptible and -resistant strains of Staphylococcus aureus were all susceptible to the glycylcyclines (MIC90 < or = 1 microgram/ml). Streptococci (including Streptococcus pneumoniae) and Enterococcus faecalis and Enterococcus faecium displayed a bimodal distribution of susceptibility to tetracycline yet were uniformly susceptible to the glycylcyclines (MIC90 < or = 0.25 microgram/ml). The glycylcyclines were highly potent against Neisseria, Moraxella, Haemophilus, and Bacteroides spp. (MIC90 < or = 0.5 microgram/ml). Strains of Chlamydia spp. (three C. trachomatis strains and one C. pneumoniae strain) were inhibited by < or = 0.25 microgram of CL 329,998 or CL 331,002 per ml. Two strains of Mycoplasma pneumoniae were inhibited by < or = 0.12 microgram of CL 331,002 per ml and by 1 microgram of CL 329,998 per ml. Mycobacterium tuberculosis and Mycobacterium avium were resistant to the two glycylcyclines (MIC > or = 8 micrograms/ml). These results indicate that the two glycylcyclines have potent in vitro activities against a wide range of clinically important pathogenic bacteria.
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PMID:In vitro activities of two glycylcyclines. 806 44

The in vitro potency and in vivo efficacy of Q-35, a new fluoroquinolone, against Mycoplasma pneumoniae were investigated by pharmacokinetic studies with M. pneumoniae-infected hamsters. By using fluoroquinolones, macrolides, and tetracyclines as references, Q-35 was found to possess the greatest mycoplasmacidal activity. The MIC for 90% of strains tested (MIC90) and the MIC50 were 0.78 and 0.39 microgram/ml, respectively, and the MBC for 90% of strains tested (MBC90) and the MBC50 were 3.13 and 0.78 microgram/ml, respectively. The MBC50-to-MIC50 ratio for Q-35 was 2. Furthermore, only Q-35 continued to be effective against 19 strains of erythromycin-resistant mutants of M. pneumoniae. The efficacies of fluoroquinolones against M. pneumoniae were also investigated by using an experimental hamster pneumonia model to measure the CFU of M. pneumoniae in the lungs. Q-35 and ofloxacin were efficacious following oral administration of 200 mg/kg/day for 5 days, initiated 24 h after infection, while ciprofloxacin was not active. Continuous administration of Q-35 for 10 days significantly reduced numbers of viable M. pneumoniae in the lungs. These results suggest that both Q-35 and ofloxacin are effective in the early phase of infection and, moreover, that Q-35 is also effective in the middle stage of infection, when progressive lung alterations and continuous increases in mycoplasmal growth occur. Peak levels of Q-35 in sera and lungs after oral administration were higher than those of ciprofloxacin but lower than those of ofloxacin. On the basis of these results, Q-35 appears to be a promising antimicrobial agent in chemotherapy of mycoplasmal infection.
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PMID:In vitro and in vivo activities of Q-35, a new fluoroquinolone, against Mycoplasma pneumoniae. 823 90


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