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H Thadepalli

Publications and source records attributed to H Thadepalli.

At least 73 records · Page 4Linked to original sources
PubMed1983

Penicillin failure in the treatment of Bacteroides fragilis lung abscess. Experimental study in rabbits.

Carbenicillin, chloramphenicol, doxycycline, and clindamycin were compared with penicillin for the treatment of lung abscess in an animal model produced by transtracheal inoculation of a mixture of anaerobes: Bacteroides fragilis, Peptococcus morbillorum, Eubacterium lentum and Fusobacterium nucleatum. Both chloramphenicol and doxycycline eliminated the bacteria but failed to close the abscess cavity. Carbenicillin, although it eradicated B. fragilis, failed to close the abscess cavity in 3 of 6 animals. In all animals tested, clindamycin sterilized the abscess cavities and healed the lung abscesses, while penicillin failed to eradicate the infection. Clindamycin was significantly more effective than penicillin in the elimination of anaerobic bacteria from the lung (p less than 0.05). Clindamycin also closed the abscess cavity faster than penicillin (p less than or equal to 0.02). The superior efficacy of clindamycin may have been the result of accumulation in the lung tissue in concentrations four- to eightfold higher than in the serum.

Animals↗
PubMed1982

Amniotic fluid analysis for antimicrobial factors.

The antimicrobial factors in amniotic fluid (AF) were analyzed in 81 women during various periods of gestation. The AF inhibited the growth of E. coli 026 when the phosphate/zinc ratio was less than 200 or iron less than or equal to 1.2 microgram/ml and unbound transferrin was greater than 40%. A heat-stable non-lysozymal phosphate insensitive cationic protein with molecular weight higher than transferrin was also found in inhibitory AF. The antimicrobial properties of AF did not correlate with absolute zinc or lysozyme levels. The AF was non-inhibitory when it contained greater than 60 +/- 5 micrograms/ml of phosphate with phosphate/zinc ratio greater than 200, iron greater than 1.2 microgram/ml and unbound transferrin was less than 40%. Amongst all criteria described, iron (P = 0.002) and unbound transferrin levels (P = 0.0005) were the most reliable and consistent all through pregnancy but others were highly reliable only during the 36th-40th week of gestation. The clinical application of these factors are being investigated.

Amniotic Fluid↗
PubMed1982

In vitro activity of pipecolic acid amide of clindamycin (U-57930E) on anaerobic bacteria compared with those of clindamycin, cefoxitin, and chloramphenicol.

In vitro activity of pipecolic acid amide of clindamycin (U-57930E) against 265 isolates of anaerobic bacteria, including 66 strains of Bacteroides fragilis, was compared with those of clindamycin, chloramphenicol, and cefoxitin. At therapeutically achievable concentrations, the activities of all four antibiotics against anaerobic bacteria were similar.

Bacteria, Anaerobic↗
PubMed1982

Chemoprophylaxis of anaerobic pulmonary infections. An experimental study in rabbits.

Chemoprophylaxis of anaerobic pulmonary infection due to aspiration was studied in a rabbit model with the view of comparing the efficacy of procaine penicillin, clindamycin, chloramphenicol, doxycycline and cefoxitin. The antibiotic treatment was commenced immediately following transtracheal inoculation of a mixture of Bacteroides fragilis, Streptococcus morbillorum, Fusobacterium nucleatum and Eubacterium lentum. Treatment was stopped after 48 h and lungs were examined for evidence of infection on the 10th day. Only clindamycin and carbencillin were highly efficacious in chemoprophylaxis and both drugs prevented pulmonary infection in 7 of 8 (87%) of the animals tested.

Anaerobiosis↗
PubMed1982

In vitro activity of BU-2313B against anaerobic bacteria.

The antimicrobial efficacy of BU-2313B, a new antibiotic, was evaluated in comparison with clindamycin, chloramphenicol and cefoxitin against 265 clinical anaerobic isolates. BU-2313B inhibited 88% of 66 isolates of Bacteroides fragilis tested at 2 micrograms/ml, whereas clindamycin, chloramphenicol and cefoxitin inhibited 98, 97 and 92% of them at 2, 8 and 16 micrograms/ml, respectively. BU-2313B was severalfold more effective than chloramphenicol and cefoxitin, but it was eight times less effective than clindamycin.

Aminoglycosides↗
PubMed1982

Cyclic changes in cervical microflora and their effect on infections following hysterectomy.

In a prospective study the cyclic changes in the cervical microflora and the endometrial histology were correlated with the incidence of postoperative infections in 99 women undergoing elective abdominal hysterectomy. Escherichia coli and Bacteroides fragilis were isolated more frequently during the proliferative phase than during the secretory phase and, correspondingly, postoperative infections were more frequent when operated during the proliferative phase than during the secretory phase. Moderate to severe infections occurred in 31.6% of the patients operated during the proliferative phase in contrast to 18% during the secretory phase. This suggests increased host susceptibility to infection during the proliferative phase.

Adult↗
PubMed1982

Rapid differentiation of bacterial meningitides by direct gas-liquid chromatography.

Rapid identification of Haemophilus influenzae and other bacillary meningitides was attempted by gas-liquid chromatography (GLC) of the metabolic by-products in broth cultures and in cerebrospinal fluid (CSF) samples obtained from experimental meningitis produced in New Zealand White male rabbits. These results were correlated with the GLC of CSF of meningitis patients. A major peak with retention time of succinic acid was found in the broth cultures of all bacilli tested including H. influenzae, Escherichia coli, Enterobacter cloacae, Klebsiella pneumoniae, Proteus mirabilis, Citrobacter freundii, Pseudomonas aeruginosa, and Listeria monocytogenes. Succinic acid was also found in the CSF of experimental meningitis and in the CSF of all patients with H. influenzae and Esch. coli meningitis. This peak was not detected in the blood samples of experimental animals. It was also absent in the broth cultures of all of the gram-positive and gram-negative cocci tested, such as Streptococcus pneumoniae and Neisseria meningitidis. Succinic acid, which appears to be a by product of fermentation, persisted as a clear cut marker in H. influenzae meningitis for at least 3 d after the initiation of treatment. In one patient, the succinic acid peak disappeared during treatment and reappeared with a clinical relapse. Clearly, the presence of succinic acid that can be rapidly detected by GLC in the CSF excludes pneumococcal or meningococcal meningitis and strongly suggests H. influenzae or other bacillary meningitides.

Animals↗
PubMed1982

Imaging endocarditis with Tc-99m-labeled antibody--an experimental study: concise communication.

The sensitivity and specificity of Tc-99m-labeled antibacterial antibody (Tc-99m Ab) for detecting bacterial endocarditis were evaluated in an experimental model. Rabbit-produced antistaphylococcal antibody was extracted using Rivanol and chemically labeled with Tc-99m. This Tc-99m Ab was injected intravenously in New Zealand rabbits 24 hr after producing Staphylococcus aureus endocarditis of the aortic valve. Imaging and tissue analyses were performed on the following day. All 11 animals developed S. aureus aortic-valve vegetations and showed increased uptake of Tc-99m Ab at the aortic valve, 118 times higher than at the uninfected tricuspid valve. Although high hepatic radioactivity and anatomic uncertainties interfered with in vivo delineation of these lesions, images of the excised hearts showed all affected valves. Two rabbits inoculated with Escherichia coli did not develop endocarditis and had little uptake of Tc-99m Ab, while six rabbits with enterococcal endocarditis had no uptake of the Tc-99m Ab in their vegetations. The findings suggest potential value of Tc-99m Ab on the rapid diagnosis of endocarditis.

Animals↗
PubMed1982

Polymicrobial genital gangrene (Fournier's gangrene): clinical, microbiologic, and therapeutic features.

The microbiologic and therapeutic aspects of polymicrobial genital gangrene (Fournier's gangrene) studied in nine patients are presented. Seven patients had both aerobic and anaerobic bacteria isolated from the site of infection; four had Bacteroides and two, Clostridia. Broad-spectrum penicillins such as ticarcillin, mezlocillin, and piperacillin, or combined clindamycin and gentamicin therapy were used. One patient died of fulminating infection and eight patients were cured of their infections. Anaerobic bacteria and appropriate antibiotic therapy should be considered in all patients with genital gangrene.

Adult↗
PubMed1981

Animal model for anaerobic lung abscess.

There are no satisfactory animal models for the study of anaerobic lung abscess. Aspiration of food, gastric mucin, or hydrochloric acid, or any combination of these, along with oropharyngeal bacteria, is commonly believed to cause aspiration pneumonia and lung abscess. In the animal model described, none of the adjuvants was effective in producing anaerobic lung abscesses. Anaerobic bacteria derived from dental scrapings of a healthy adult (Peptococcus morbillorum, Fusobacterium nucleatum, Eubacterium lentum, and Bacteroides fragilis), when inoculated transtracheally without any adjuvants into New Zealand male white rabbits, consistently produced lung abscesses. Neither B fragilis by itself nor a mixture of P. morbillorum, F. nucleatum, and E. lentum without the addition of B. fragilis produced lung abscesses. The bacterial isolates used in this study were stored in prereduced chopped-meat-glucose medium and subcultured several times and were found effective in reproducing anaerobic lung abscesses repeatedly. This animal model is suitable for the study of pathogenesis, diagnosis, and treatment of B. fragilis-associated anaerobic lung abscess.

Aerosols↗
PubMed1981

Antimicrobial activity and synergism of cefuroxime on anaerobic bacteria.

In vitro efficacy of cefuroxime was tested against 333 clinical isolates of anaerobic bacteria, including 80 strains of Bacteroides fragilis. Its activity was compared with that of cefamandole and cefoxitin. In addition, the antimicrobial synergism of cefuroxime was tested in combination with either penicillin or carbenicillin against B. fragilis. At 16 microgram/ml, cefuroxime inhibited 70% of all anaerobic bacteria, but it was ineffective against 64% of B. fragilis strains tested. Cefuroxime in combination with penicillin or carbenicillin exerted excellent synergistic activity against two of the three isolates of B. fragilis tested and had an additive effect on the other. Although cefuroxime by itself is ineffective against B. fragilis, it acts synergistically with penicillin or carbenicillin.

Anaerobiosis↗
PubMed1981

Is penicillin alone effective in enterococcal endocarditis? An experimental study in rabbits.

Enterococcal endocarditis in man is traditionally treated with penicillin and an aminoglycoside. Whether penicillin alone is adequate has not been fully evaluated. Experimental enterococcal endocarditis (EEE) in male New Zealand rabbits, when untreated, was fatal in all animals within 2 weeks. When crystalline penicillin G was given at 30,000 U/day in three equally divided doses, the fatality rate was 63.3%; when the dosage was increased to 600,000 U/day, the mortality ws 37.5%, demonstrating the ineffectiveness of crystalline penicillin alone in EEE. Procaine penicillin at 300,000 U/day given as a single dose provided increased protection, but was still associated with unacceptably high mortality (17.5%). A higher dose level, 600,000 U/day, of procaine penicillin protected all animals with EEE. High and sustained levels of penicillin in the serum and the myocardium cured enterococcal endocarditis in rabbits.

Animals↗
PubMed1981

Spinal epidural abscess due to Actinomyces israelii.

A 31-year-old man had back pain, weight loss, fever, and paraplegia, with radiographic evidence of a left upper lobe lesion and lytic lesions in ribs and vertebral bodies. Gallium uptake was increased over the spine. At surgery we found a paraspinal abscess due to Actinomyces israelii. The patient responded to surgery and penicillin therapy. This is the first report of a case of actinomycotic spinal epidural abscess necessitating emergency surgery since the advent of penicillin.

Abscess↗