Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Whether tuberculosis patients received short-course chemotherapy with treatment of isoniazid (INH) and rifampicin (RIF), combined or not with pyrazinamide (PZA) and ethambutol (EMB) or streptomycin (SM), or long term chemotherapy with INH, SM and thiacetazone (Tb1), the rate of sputum culture conversion was similar in HIV-positive and HIV-negative patients. To prevent relapses it was recommended to treat patients for a minimum of 9 months and for at least 6 months after culture conversion, or even to administer INH for life after the end of treatment. However, no difference was observed in the percentage of relapses between HIV-positive and HIV-negative patients. Side-effects were observed in approximately 20% of HIV-positive patients treated with INH + RIF + PZA + EMB (or SM) or with INH + SM + Tb1, Tb1 being responsible for epidermal necrolysis, in some cases fatal. The mean survival of HIV-patients with tuberculosis was from 10 to 18 months after the diagnosis of tuberculosis. Other opportunistic infections could have been the main cause of death. Acquired drug resistance is not a common complication of tuberculosis treatment in HIV-positive patients, but several epidemics of nosocomial transmission of multiple drug-resistant tuberculosis have recently been observed in the USA. Sparfloxacin, a new fluoroquinolone with a long half-life and low MIC (0.25-0.50 mg/l) against Mycobacterium tuberculosis, is a promising drug against tuberculosis.
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PMID:Treatment of tuberculosis in HIV infection. 826 Jun 70

The MIC values of the antifungal drug ketoconazole were evaluated on 66 Candida albicans strains. These strains were isolated from 26 HIV-1 infected patients with oral recurrent candidosis. Each episode of oral candidosis observed in these patients was orally treated with ketoconazole (200 mg/day) until the clinical disappearance of the lesions. The most frequent MIC values were 20 micrograms/ml and 10 micrograms/ml, observed in 37 and 19 isolates respectively. Only strains from five patients showed changes in their susceptibility to ketoconazole. This fact could indicate that a different strain causes the subsequent reappearance of the oral lesions, rather than the drug selecting resistant fungal strains. Our results stress the role of host characteristics in the occurrence of candidal infections, pointing to the progressing failure of the immunological response as the most important factor responsible for the recurrence of oral candidosis during HIV-1 infection.
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PMID:Susceptibility to ketoconazole of Candida albicans strains from sequentially followed HIV-1 patients with recurrent oral candidosis. 140 90

This prospective study evaluated the in vitro susceptibility of Candida albicans isolates recovered from the oral cavity of AIDS/ARC patients before and during long-term therapy with fluconazole. Thirty adults (15 with ARC and 15 with AIDS) with a first episode of thrush candidiasis were given oral fluconazole (Triflucan 50 mg; one capsule daily) for at least three months. Fungal susceptibility testing was performed before treatment, after one month, and at last follow-up (range 3.5-12 months; mean 5.7 months). MICs were determined using the agar dilution method with casitone (Difco 259-01) as the test medium at pH 7.2-7.4. There were two initial clinical failures (one with high MICs before and under treatment and one with an intermediate MIC initially and a rise in MIC under fluconazole). Four patients developed a clinical relapse with no change in MICs (which were low or intermediate). In six patients, clinical symptoms resolved but carriage of C. albicans persisted (low MICs). In 18 patients, clinical resolution with eradication of C. albicans was achieved. These data suggest that (1) clinical failures may be associated with in vitro resistance; (2) relapses under fluconazole maintenance therapy may develop in patients with advanced HIV disease despite the lack of change in the susceptibility of strains.
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PMID:[Treatment and secondary prophylaxis with fluconazole for oropharyngeal candidiasis in HIV-positive patients. A mycological analysis of failures]. 149 36

Analogues of peptides ranging in size from three to six amino acids and containing the hydroxyethylene dipeptide isosteres Phe psi Gly, Phe psi Ala, Phe psi NorVal, Phe psi Leu, and Phe psi Phe, where psi denotes replacement of CONH by (S)-CH(OH)CH2, were synthesized and studied as HIV-1 protease inhibitors. Inhibition constants (Ki) with purified HIV-1 protease depend strongly on the isostere in the order Phe psi Gly greater than Phe psi Ala greater than Phe psi NorVal greater than Phe psi Leu greater than Phe psi Phe and decrease with increasing length of the peptide analogue, converging to a value of 0.4 nM. Ki values are progressively less dependent on inhibitor length as the size of the P1' side chain within the isostere increases. The structures of HIV-1 protease complexed with the inhibitors Ala-Ala-X-Val-Val-OMe, where X is Phe psi Gly, Phe psi Ala, Phe psi NorVal, and Phe psi Phe, have been determined by X-ray crystallography (resolution 2.3-3.2 A). The crystals exhibit symmetry consistent with space group P6(1) with strong noncrystallographic 2-fold symmetry, and the inhibitors all exhibit 2-fold disorder. The inhibitors bind in similar conformations, forming conserved hydrogen bonds with the enzyme. The Phe psi Gly inhibitor adopts an altered conformation that places its P3' valine side chain partially in the hydrophobic S1' pocket, thus suggesting an explanation for the greater dependence of the Ki value on inhibitor length in the Phe psi Gly series. From the kinetic and crystallographic data, a minimal inhibitor model for tight-binding inhibition is derived in which the enzyme subsites S2-S2' are optimally occupied. The Ki values for several compounds are compared with their potencies as inhibitors of proteolytic processing in T-cell cultures chronically infected with HIV-1 (MIC values) and as inhibitors of acute infectivity (IC50 values). There is a rank-order correspondence, but a 20-1000-fold difference, between the values of Ki and those of MIC or IC50. IC50 values can approach those of Ki but are highly dependent on the conditions of the acute infectivity assay and are influenced by physiochemical properties of the inhibitors such as solubility.
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PMID:Hydroxyethylene isostere inhibitors of human immunodeficiency virus-1 protease: structure-activity analysis using enzyme kinetics, X-ray crystallography, and infected T-cell assays. 163 5

The in vitro susceptibility of nine Rhodococcus equi strains (seven isolates from immunocompromised patients mainly HIV positive and two reference strains) to twenty various antibiotics were assessed for bacteriostatic effects by an agar dilution method. Imipenem and ceftriaxone were the most effective of the beta-lactams studied. The lowest MIC were noted with vancomycin, teicoplanin, erythromycin, clarithromycin, rifampicin, gentamicin and doxycycline. A longitudinal survey, including three strains isolated from the same patient, showed the emergence of rifampicin resistance and a marked increase of the MIC to imipenem.
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PMID:[In vitro activity of twenty antibiotics against Rhodococcus equi]. 165 30

Susceptibility and development of resistance to 5-FC in Candida strains isolated from 4 defined groups of probands was investigated. 5-FC-susceptibility was determined in a microdilution assay in yeast nitrogen base after 24 h incubation at 37 degrees C. The range investigated ranked between 5-FC-concentrations from 0.015-16 microgram ml-1. Isolates with an MIC of greater than or equal to 16 micrograms ml-1 were regarded as 5-FC-resistant. In total 336 Candida isolates were investigated; 21 of them (= 6.3%) were found to be 5-FC-resistant. The Candida isolates were rather different with respect of their origin: 57 vaginal isolates from non-risk patients from Southern Germany comprised 5.3% 5-FC-resistant strains. 160 isolates from the urine of longtime-intensive care patients of total Germany were 5-FC-resistant with 6.3%. Of 74 isolates of different localization from intensive care patients of the University Clinics in Freiburg 10.8% were 5-FC-resistant. Among 45 isolates from the oral cavity from HIV-positive patients of the Frankfurt region no 5-FC-resistant strain was found. The epidemiology of 5-FC-resistance is mainly based on the percentage of non-albicans isolates of the proband groups (C. tropicalis, C. krusei and others), and is less based on the frequency of C. albicans serotype B isolates. In sequential observations with individual intensive care patients no increase of 5-FC-resistance in their Candida isolates could be observed with longer periods of hospitalization.
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PMID:[The resistance behavior of yeast isolates from defined patient groups to 5-fluorocytosine]. 181 69

The use of antifungal drugs in immunocompromised patients impose to the laboratory the control of the efficacy of these therapy. With fluconazole, one of the most recent antifungal agents these control use a special method (Central Research Pfizer) different of those they are used with others antifungals. We have comparatively tested, using MIC technic four broth mediums (High Resolution medium (Oxoid) YMB (Difco) YNB dextrose (Autobac) and Casitone) and three agar mediums (HR, YMA, Casitone) incubated at 28 degrees C for 24 and 48 h. The strains of yeasts are isolated from oro-pharyngeal prelevements on HIV antibody positive patients observed during six to twelve months and eventually treated by fluconazole. Sixty patients are controlled, 33 give one or more positive cultures with 74 strains of C. albicans and four other yeasts. By determination of the MICs with seven different methods we find any resistant strains with the MICs range from 3.12 to 12.5 or 25 micrograms/ml.
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PMID:[Laboratory's controls of antifungal treatment by the fluconazole of the candidiasis in immunocompromised patients]. 188 90

Infections of Rhodococcus equi, a well-known pathogen in animals which causes cavitated pneumonia similar to that caused by mycobacteria, were studied in three HIV-infected patients. This microorganism was isolated in the bronchoalveolar washings of two patients and in the sputum of the third. In two patients, Rh. equi represented the first clinical opportunistic manifestation of HIV disease. One patient died of concomitant Pneumocystis infection. The eradication of the microorganism occurred in two out of three patients. It was found that no isolates were resistant to erythromycin, claritromycin, rifampin, vancomycin, teicoplanin, imipenem, gentamycin or azithromycin (MIC values < or = 0.1 microgram/ml). Moreover, the quinolones (ciprofloxacin and ofloxacin) were found to be less effective, whereas neither the beta-lactam antibiotics nor chloramphenicol were effective therapy for this microrganism. At least two antimicrobial agents should be given contemporaneously to treat these infections for a period of up to several months. Our results suggest that the combinations erythromycin + rifampin or imipenem + teicoplanin are the most effective treatments in Rh. equi infections.
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PMID:Infections due to Rhodococcus equi in three HIV-infected patients: microbiological findings and antibiotic susceptibility. 767 72

Cryptococcus neoformans is responsible for pulmonary and meningal infections in HIV patients. The lack of effective cellular cooperation caused by the low level of CD4+ cells, and the resistance of C. neoformans to phagocytosis allows growth and persistence of the yeast in the host. We describe here an in-vitro model of intracellular replication of C. neoformans inside J774-A.1 macrophages, and the determination of the intracellular antifungal activity of amphotericin B and fluconazole alone or in association with IFN-gamma. The maximum inhibitory effect was observed with one MIC of amphotericin B and 100 or 1000 IU/mL of IFN-gamma. amphotericin B alone (at 1 x MIC), or either 1 x or 50 x MIC of fluconazole in normal or IFN-gamma activated macrophages, did not eradicate the ingested yeast. A potential underlying mechanism of the synergy of amphotericin B in IFN-gamma primed macrophages was investigated by measurement of nitrite level and by use of the NO synthase competitive inhibitor, NG-monomethyl L-arginine (NMMA). One MIC of amphotericin B was able to activate the synthesis of nitrogen reactive intermediates in IFN gamma-primed macrophages. NMMA treated infected macrophages responded less well to IFN-gamma priming, resulting in a moderate inhibition in subsequent amphotericin B exposure.
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PMID:Synergic inhibitory activity of amphotericin-B and gamma interferon against intracellular Cryptococcus neoformans in murine macrophages. 773 Feb 21

A comparative open study was performed to evaluate the efficacy of single doses of ciprofloxacin (500 mg) and trimethoprim-sulfamethoxazole (TMP-SMZ; 640 mg/3,200 mg) for the treatment of culture-proven chancroid. Clinical cure or improvement was observed 7 days after treatment in 32 (76.2%) of the 42 patients who received ciprofloxacin and 21 (52.5%) of the 40 patients who received TMP-SMZ (P = .04). Cultures for one (4.5%) of 22 patients not cured with ciprofloxacin and 16 (59.3%) of 27 patients not cured with TMP-SMZ were still positive for Haemophilus ducreyi 7 days after treatment (P < .001). Although 77 (71.3%) of the 108 patients tested were seropositive for HIV-1 antibody, HIV infection and the degree of CD4+ lymphocyte depletion had no effect on clinical and bacteriologic outcome. All isolates of H. ducreyi were highly susceptible to ciprofloxacin (MIC, 0.004-0.06 mg/L). In contrast, resistance to TMP-SMZ (MIC, > or = 4/76 micrograms/mL) was observed in 48.9% of isolates (22 of 45) and was significantly associated with treatment failure. Therefore, the administration of TMP-SMZ, in single or multiple doses, is no longer indicated for the treatment of chancroid in Rwanda.
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PMID:Failure of treatment for chancroid in Rwanda is not related to human immunodeficiency virus infection: in vitro resistance of Haemophilus ducreyi to trimethoprim-sulfamethoxazole. 779 96


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