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)

Twenty-five patients with chronic bronchitis were studied intensively from 1968 to 1972. Viral, bacteriologic, mycologic, and mycoplasmal studies, both serologic and cultural, were carried out in an attempt to determine the role these agents play in exacerbations. All of the usual viral agents associated with exacerbations and 2 members of the coronavirus group, 229E and OC43, were detected. One third (33.6 per cent) of the 116 exacerbations observed could be related to viral infection or Mycoplasma pneumoniae (1 exacerbation). Viral infection was also noted to occur during periods of remission but was more commonly associated with periods of exacerbation(P less than 0.001). No interrelationship between viral and bacterial infection was apparent and neither Streptococcus pneumoniae nor Haemophilus influenzae was present more frequently in the sputum of patients in exacerbation. However, the number of S. pneumoniae organisms present in the sputum was significantly greater (P=0.04) during exacerbation than during remission and their presence was significatnly correlated with increases sputum purulence (P LESS THAN 0.01). This was not true of H. influenzae. Ampicillin was effective in clearing the sputum of S. pneumoniae but not of H. influenzae; the reverse was true of tetracycline.
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PMID:Role of infection in chronic bronchitis. 126 52

A series of O-alkylated derivatives of erythromycin (EM) has been prepared and their biological properties were evaluated. Among them, clarithromycin (CAM, 6-O-methylerythromycin) exhibits most potent in vitro and in vivo antibacterial activities, higher acid-stability than EM and favorable pharmacokinetic properties as an antibiotic. CAM was originally synthesized via methylation of 2'-O,3'-N-bis(benzyl-oxycarbonyl)-N-demethylerythromycin in low yield, because of the less selectivity of 6-O-methylation. The selective 6-O-methylation was achieved using the erythromycin 9-oxime derivative as a key intermediate. By the further investigation on the protective groups of 9-oxime and desosamine moiety, the production process of CAM on an industrial scale has been established via methylation of 2',4''-O-bis(trimethylsilyl)erythromycin 9-[O-(1-isopropoxycyclohexyl)oxime] in more than 45% overall yield. CAM has the same antibacterial spectra as EM and is active against aerobic Gram-positive bacteria, some Gram-negative bacteria, anaerobic bacteria, Mycoplasma and Chlamydia. The activity of CAM against clinical isolates was 1 to 16 times higher than that of EM. The efficacies of CAM were 6 to 15 times superior to those of EM against systemic infections due to Gram-positive bacteria in mice. CAM also showed more potent therapeutic efficacies than EM against respiratory tract infections caused by S. pneumoniae and H. influenzae. CAM was well absorbed after oral administration, and its distribution to various tissues was significantly higher than that of EM in animals. The level of CAM in the lung was extremely high, which accounted 69 times that of EM. CAM was found to be distributed predominantly in the alveolar wall, especially in the alveolar epithelial cells, by microautoradiography. After oral administration in human, the serum level and urinary excretion of CAM were 5 and 20 times higher than those of EM, respectively. The major and active metabolite of CAM in human, (14R)-14-hydroxyclarithromycin, existed in significant quantity in the serum and urine, suggesting that the metabolite contributes to the excellent clinical efficacy of CAM. This paper describes the synthesis, structure-activity relationships, antibacterial activities, metabolism and clinical efficacies of CAM, a new macrolide antibiotic.
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PMID:[Research and development of clarithromycin]. 146 9

Table 5 summarizes the activity of the newer quinolones against various bacteria including intracellular bacteria and the other microorganisms. In this table, the overall MIC ranges of NFLX, ENX, OFLX, and CPFX, for susceptible isolates of each bacteria are schematically presented. The newer quinolones are considered to have sufficient activity against gram-negative enteric bacteria, N. gonorrhoeae, and H. influenzae and Legionella spp. Since OFLX and CPFX show only moderate activity against staphylococci, streptococci, and P. aeruginosa, improvement is expected. As shown in Table 3, TFLX and the recent investigational quinolones such as SPFX and KB-5246 show higher and promising activity against gram-positive bacteria. However, further studies are needed with longer periods to indicate whether these newer agents will be able to stop the increase of quinolone-resistant staphylococci. Furthermore, the activity of the newer quinolones against obligate anaerobes such as clostridia and bacteroides are considered to be insufficient for clinical use. Whether it will be possible to synthesize quinolones with anti-anaerobic activity sufficiently for clinical treatment is uncertain. Although Mycobacterium tuberculosis is susceptible to the newer quinolones, other mycobacteria are somewhat less susceptible to this class of agents. In addition, the newer quinolones have adequate activity against mycoplasma, chlamydia and rickettsia. From a microbiological viewpoint the prospects for the newer quinolones would be primarily to find agents that have higher anti-staphylococcal and anti-streptococcal activity. Secondly, agents possessing superior activity against obligate anaerobes such as Bacteroides spp. and Clostridium spp. are expected to synthesize. Furthermore, it may be possible to synthesize compounds that are sufficiently active for clinical use against atypical mycoplasma, chlamydia, and rickettsia.
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PMID:In vitro properties of the newer quinolones. 160 15

This ether oxim derivative of erythromycin A is an easy to absorb oral antimicrobial somewhat less effective in vitro than erythromycin. At relatively low MIC's it is active against staphylococci, streptococci, pneumococci, branhnamella and chlamydiae, higher concentrations are needed against enterococci and some strains of H. influenzae. Roxithromycin is also reported to have a very good effect on campylobacters, many anaerobic bacteria, Toxoplasma gondii, Treponema pallidum, Mycoplasma pneumoniae and Legionella pneumophilla. Its half-life in the serum of healthy individuals ranges from 9 to 16 hours. Maximum serum concentrations at 2 oral doses of 150 mg a day are reached at 3 to 4 days and vary from 5.5 to 11.1 mg/l. The distribution of roxithromycin in body tissues is excellent. In a group of 57 patients treated for various infections of clear etiology the positive therapeutic effects resulting in the state of bacteriological negativity was reached in 86% of cases. Roxithromycin can be recommended as a drug of choice in mild or less severe cases of infection caused by agents sensitive to this antimicrobial. Its excellent tolerance makes it especially well suited for use in pediatric practice.
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PMID:Roxithromycin--a new macrolide derivative. 269 62

From December 1984 to June 1986, a prospective clinical trial was carried out in 48 patients with acute community-acquired pneumonia, comparing 2 possible therapeutic schemes: one, using only one antibiotic (roxithromycin: RXT) presumptively active on most of the germs usually involved. In a second group, the identification of the germs involved was attempted on the basis of clinical, epidemiological and radiological data, followed by treatment with the antibiotic/s (ATB) known to be more active against the suspected organisms. The dosage of RXT was 300 mg/day, orally during an average of 9 days. The mean duration of treatment in ATB group was 12 days. In both groups, the following microorganisms were identified: RXT group: St. pneumoniae (13 cases), H. influenzae (1), B. catarrhalis (1); mixed infections: St. pneumoniae + H. influenzae (2); Mycoplasma pneumoniae (3) and 4 patients with unidentified germ; in ATB group: St. aureus (3), St. pneumoniae (5), H. influenzae (2), B. catarrhalis (1); mixed infections: St. aureus + Enterobacter + E. coli (1); Mycoplasma pneumoniae (2) and 10 patients with unidentified germ. The therapeutic results were satisfactory (curation rate: 92%) and similar for both groups of treatment, concluding that both schemes are comparable. Therefore, the choice for one or the other scheme should be based on other reasons, such as easy administration and cost of the treatment.
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PMID:[Comparison of empirical treatment with antibiotics in community acquired lung diseases]. 269 35

Community-acquired pneumonia accounts for about 1 p. 100 of all lower respiratory infections, i.e. 1 to 10 cases per 1,000 adults annually, depending on the country and the year. The causative organism is seldom identified since there is no simple, specific, non-invasive and cheap laboratory diagnostic method. Treatment therefore is empirical. It rests upon epidemiological and clinical data as well as upon a set of criteria concerning the acceptability of antibiotics and variations in bacterial resistance. The four principal antibiotic-sensitive microorganisms to be taken into account are pneumococci, Haemophilus influenzae, Mycoplasma pneumoniae and Legionella pneumophila. In practice, focal lung infections should initially be treated with penicillin A which is active against pneumococci and H. influenzae. In case of atypical pneumonia, preference should be given to macrolides since these drugs are active against M. pneumoniae and L. pneumophila. In initially severe or worsening pneumonia occurring in debilitated patients penicillins and macrolides should be given concomitantly from the start.
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PMID:[Community-acquired pneumonia]. 274 47

Twelve oral antimicrobial agents were tested for their antimicrobial activities against causative organisms isolated from pediatric infections. Activities of these antimicrobial agents against Streptococcus pyogenes were also examined in relation to T-antigen typing of the species. The results of the investigation are summarized as follows. 1. Against Staphylococcus aureus, rokitamycin (RKM), josamycin, ofloxacin, minocycline exhibited strong antimicrobial activities, and few strains of S. aureus showed resistance to these antimicrobial agents. More strains exhibited resistance to erythromycin (EM) than to other macrolide antibiotics (MLs) examined. Amoxicillin (AMPC)-resistance was often observed also. 2. Against S. pyogenes, beta-lactam antibiotics (beta-lactams) and RKM had MIC80 of 0.20 microgram/ml or below, and no resistant strains of this organism were observed against these antibiotics. Only 2 resistant strains (2.0%) of S. pyogenes to MLs were detected, but resistance to tetracyclines (TCs) was observed at a high frequency, with 71.4% or more strains among T-4, T-6, T-12 and T-28 antigen types exhibited resistance to TCs. Among the 21 strains of T-12 antigen type examined, only one strain (4.8%) was found resistant to MLs. These observations suggested that the reduction in the frequency of ML-resistant strains was not due to the reduction in the number of T-12 antigen type strains but due to losses of resistance factors against MLs of plasmids. 3. Antibacterial activities of beta-lactams and MLs against Streptococcus pneumoniae strains were good, similarly to activities against S. pyogenes. But many strains of S. pneumoniae were resistant to TCs. 4. New quinolone antimicrobial agents (quinolones) showed excellent activities against Branhamella catarrhalis strains with EM and RKM showing the next best activities. The number of resistant strains against quinolones, however, seemed to be on an increase. 5. Quinolones had strong antimicrobial activities against Haemophilus influenzae, few strains of which showed resistance to quinolones. AMPC had the next best activity, but approximately 10% of H. influenzae exhibited resistance to this antibiotic. 6. Against Campylobacter spp., quinolones and MLs showed the best activities with MIC80 values at or below 0.25 microgram/ml, and no resistant strains of the species against these antimicrobial agents were observed. Fosfomycin and TCs showed somewhat inferior activities to quinolones and MLs, with beta-lactams showing still lower activities. 7. Only few strains of Mycoplasma pneumoniae and Chlamydia trachomatis were examined, but MLs and TCs appeared to be effective against these organisms.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:[Studies on susceptibility of isolated organisms from pediatric infections against various antimicrobial agents]. 305 Jan 84

Cigarette smoking exerts deleterious effects not only on the respiratory tract, but also on the lung's parenchyma. The FEV is reduced in heavy chronic smokers. Persistent smoking has an unfavourable influence on mucociliary activity. According to the results of recent research almost 8 million people in the U.S. were suffering from chronic bronchitis in 1981. There is a direct correlation between the number of cigarettes smoked, over what period of time, and the incidence of chronic bronchitis. In studies with patients suffering from exacerbations of chronic bronchitis the most common bacterial pathogens found were Haemophilus influenzae, Streptococcus pneumoniae and Branhamella catarrhalis. Mycoplasma pneumoniae and certain viruses are counted amongst the non-bacterial pathogens. Antibiotics should be effective against such possible pathogens. The resistance of H. influenzae to ampicillin/amoxicillin is currently observed in at least 12% of cases, whilst H. influenzae is regularly observed to be resistant to erythromycin. Cefaclor, trimethoprim/sulphamethoxazole and amoxicillin/clavulanic acid offer satisfactory forms of treatment. Pneumonia caused by S. pneumoniae, H. influenzae, B. catarrhalis and Legionella pneumophila is often seen in smokers and patients with COLD. Haemocultures should be prepared for all hospitalized patients. Penicillin G and/or V is the agent of choice. Cefaclor or trimethoprim/sulphamethoxazole can be given to counter beta-lactamase producing H. influenzae whilst cefaclor, erythromycin, tetracycline or trimethoprim/sulphamethoxazole are used for the treatment of B. catarrhalis infections. In Legionella infections erythromycin is the preferred treatment. A combination of erythromycin and cefamandole or ceftriaxone is indicated for empirical management. Patients with COLD should be immunised with pneumococcus and influenza vaccines.
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PMID:[Smoking and lower respiratory tract infection]. 361 Mar 32

The presence of viral infection was evaluated in 160 children older than three months with bacterial meningitis who were admitted to Children's Medical Center or Parkland Memorial Hospital, Dallas, TX, between October 1979 and March 1982. Results were compared with a single serologic specimen in 138 children without meningitis. A recent history of upper respiratory infection was obtained from 60% of patients, including 10/13 with pneumococcal, 9/16 with meningococcal, and 77/131 with Haemophilus influenzae meningitis. Viral infection was documented by serologic response (23.8%) or viral isolation (13.2%) in 63/160 (40%) of patients with meningitis. There were 23 positive cultures (one patient with both adenovirus and respiratory syncytial virus). Picornaviruses, including two rhinoviruses, were isolated from six of the 24 subjects without meningitis who had viral cultures. There were 69 serologic conversions in meningitis patients, with 12 patients converting to two organisms and four patients converting to three organisms. Viral diagnoses included: adenovirus, 32 children; respiratory syncytial virus, 14; influenza A, 8; influenza B, 4; parainfluenza (1, 2, and 3), 12; picornaviruses, 9; herpes simplex virus, 1; and cytomegalovirus, 1. Additionally, 6/15 seroconverted to Mycoplasma pneumoniae. The acute geometric mean serum antibody titers of meningitis patients were lower than those of the comparison group for adenovirus (3.5 vs. 6.6, p less than or equal to 0.001) and influenza B (1.2 vs. 1.6, p less than or equal to 0.05). Twenty nine of 131 patients with H. influenzae had evidence of recent adenovirus infection. Primary infection with adenoviruses and possibly influenza B or mycoplasma precedes development of bacterial meningitis in some patients and may be a predisposing factor.
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PMID:Possible association of mycoplasma and viral respiratory infections with bacterial meningitis. 381 56

In a retrospective study covering a 13-year period and a population of 817,900 inhabitants, 13 cases of invasive infection caused by Haemophilus species other than Haemophilus influenzae were found. Ten of the infectious episodes were caused by Haemophilus parainfluenzae and three by Haemophilus aphrophilus. The clinical manifestations comprised endocarditis, meningitis, pleuropneumonia, epiglottitis and septicaemia from an unknown focus. These 13 infectious episodes caused by uncommon Haemophilus species constituted less than 3% of the total number (473) of invasive Haemophilus infections registered during the same period of time. Invasive H. influenzae infections were more common in all age groups than infections caused by other Haemophilus species. In contrast to H. influenzae infections, which predominate in childhood, invasive infections due to uncommon Haemophilus species had no predilection for any age group.
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PMID:Invasive infections caused by Haemophilus species other than Haemophilus influenzae. 387 45


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