Production of alternaria mycotoxins by Alternaria alternata isolated from weather-damaged wheat.

The production of Alternaria mycotoxins by Alternaria alternata isolated from Chinese weathered wheat kernels were first investigated on polished rice and durum wheat grains. These mycotoxins included alternariol (AOH) and its monomethyl ether (AME), altenuene (ALT), altertoxin I (ATX-I), and tenuazonic acid (TA). Of 25 isolates tested, all were AOH and AME producers, 21 (84%) coproduced ALT and ATX-I, and 8 (32%) produced TA in rice culture. TA was the most abundant toxin produced at a level ranging from 1,369 to 3,563 mg/kg. Much smaller amounts of AOH, AME, ALT, and ATX-I were present with average concentrations of 54, 40, 44, and 8 mg/kg, respectively. There were linear correlations between the level of AOH and AME (r = 0.846), alternariols (AOH plus AME) and ALT (r = 0.785), and ATX-I and TA (r = 0.553). Polished rice medium seems to support a bit more production of Alternaria metabolites than wheat but with an insignificant difference in concentrations (P > 0.05). A study of the time-course of toxin production by A. alternata isolates indicated that AOH production began faster than any other toxins monitored, and ALT production exhibited a progressive increase throughout the experiment. TA producers might reveal their considerably higher ability to produce toxin in the field despite their low frequency.

Disseminated infection with Trichosporon asahii.

Trichosporon fungaemia and disseminated, purpuric, papular skin lesions developed on the head, trunk and extremities of a 5-year-old female with acute lymphocytic leukaemia. Histopathologically, the skin lesions demonstrated dermal budding yeasts. She died despite treatment with antifungal drugs. The isolate from the blood was further identified morphologically and physiologically as Trichosporon asahii, based on the revision of the genus Trichosporon by Guého et al. (1992). According to the new revision, T. asahii is the only taxon regularly involved in systemic mycoses, so that most of the isolates previously reported as T. beigelii (formerly, T. cutaneum) in human deep mycoses are now thought to belong to T. asahii.

Isolation of Rhizopus microsporus var. rhizopodiformis in the ulcer of human gastric carcinoma.

Gastric zygomycosis in a patient with gastric cancer was described. Colonization was diagnosed because broad sparsely septate hyphae were identified in the necrotic tissue of gastric biopsied specimens. No fungus was present within viable tissue. Positive cultures for Rhizopus microsporus var. rhizopodiformis were obtained from fragments of biopsied specimens. Members of the Mucorales have rarely been isolated from the culture of endoscopically biopsied materials.

Protothecosis in a patient with systemic lupus erythematosus.

A rare case of protothecosis in a 40-year-old Japanese woman with systemic lupus erythematosus, under long-term prednisolone treatment is presented. The patient developed extensive ulcerative skin lesions after injury. The characteristic histopathological findings and biochemical sugar assimilation tests indicated infection by Prototheca wicherhamii. The lesions improved following treatment with amphotericin B. The immunodeficient state of this patient seemed to contribute to the infection with Prototheca.