Steve Hernandez

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A new beta-lactam antibiotic, named thienamycin, was discovered in culture broths of Streptomyces MA4297. The producing organism, subsequently determined to be a hitherto unrecognized species, is designated Streptomyces cattleya (NRRL 8057). The antibiotic was isolated by adsorption on Dowex 50, passage through Dowex 1, further chromatography on Dowex 50(More)
A number of actinomycetes isolated from soil were found to produce one or more members of a new family of antibiotics, the cephamycins, which are structurally related to cephalosporin C. The cephamycins were produced in submerged fermentation in a wide variety of media by one or more of eight different species of Streptomyces, including a newly described(More)
Outbred ICR mice were rendered neutropenic, infected intravenously with Fusarium solani and treated orally with voriconazole. When given alone, voriconazole was not protective up to 40 mg/kg/day. When grapefruit juice was administered before infection, mice were protected by voriconazole. The mechanism may be inhibition of gut mucosal cytochrome enzymes(More)
A patient with azole-refractory thrush-esophagitis responded initially to caspofungin, but the treatment eventually failed. In a murine model, caspofungin was effective against two early isolates for which the MICs of caspofungin were low, but it was less effective against a late isolate for which the MIC of caspofungin was greater. We concluded that there(More)
Caspofungin is a potent antifungal inhibiting glucan synthesis in Candida species. However, caspofungin is not 100% curative in candidiasis. Therefore, we evaluated combinations of fluconazole with caspofungin for murine candidemia. We could not show any benefit of combined therapy over individual antifungal drugs.
Fosfomycin, a nontoxic broad-spectrum antibiotic, different in structure from all previously described antibiotics, acts selectively by inhibiting cell wall formation. It was overlooked during many years of screening because of antagonism by culture medium ingredients and frequent occurrence of resistant mutants. It is effective in many because the(More)
Paraherquamide was 98 to 100 per cent effective against six-day-old Trichostrongylus colubriformis infections in gerbils when given as single oral doses of 1.56 mg kg-1 and above. Doses of 0.78 or 0.39 mg kg-1 were 96 and 66 per cent effective, respectively. A single oral dose of 200 mg kg-1 was well tolerated.
Posaconazole and/or amphotericin B was given to mice pretreated with a steroid and then infected by inhalation of Aspergillus flavus conidia. Two laboratories conducted studies using almost identical protocols to evaluate both survival and lung tissue burdens 8 days after infection. The results of the in vivo studies performed at both laboratories were(More)