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Biomedical subjects

S H Alves

Publications and source records attributed to S H Alves.

At least 19 recordsLinked to original sources

In vitro activities of new and conventional antimycotics against fluconazole-susceptible and non-susceptible Brazilian Candida spp. isolates.

The substantial increase in the rate of azole resistant Candida spp. yeast infections has become a serious treatment problem requiring new and more active antifungal agents. In this study, the in vitro activities of ravuconazole and albaconazole were compared with those of amphotericin B, flucytosine, itraconazole and fluconazole against 162 Brazilian isolates of Candida spp. from which 48 isolates had previously shown lower susceptibility or resistance to fluconazole. Ravuconazole susceptibility ranged from 84.6% (Candida albicans) to 100% for other species and albaconazole MIC(90) was < or =1.0 microg ml(-1) for all the species emphasising the potent activity of these triazoles. To our knowledge this is the first study evaluating the susceptibility of C. dubliniensis to albaconazole.

Antifungal Agents↗

Anxiogenic effects in the rat elevated plus-maze of 5-HT(2C) agonists into ventral but not dorsal hippocampus.

The effect of the non-selective 5-HT2C receptor agonist trifluoromethyl-phenylpiperazine (TFMPP, 0.75, 1.5 and 3.0 microg) and the preferential 5-HT2C agonist 6-chloro-2(1-piperazinyl)pyrazine (MK-212, 0.1, 0.3 and 1.0 microg) microinjected into the ventral or dorsal hippocampus was investigated in anxiety measures of rats exposed to the elevated plus-maze test. Ventral hippocampal (VH) microinjections of the 0.75 or 1.5 microg doses of TFMPP reduced open-arm exploration without affecting the number of closed-arm entries, indicating a selective anxiogenic profile. The highest dose (3.0 microg) reduced open- and closed-arm entries, suggesting interference in locomotor activity. The 0.1 microg dose of MK-212 also caused a selective anxiogenic effect when microinjected into the ventral hippocampus, without disturbing locomotor activity. Microinjections of the two higher doses of MK-212 (0.3 or 1.0 microg) into the ventral hippocampus led to a decrease of exploration in both arms of the maze. In contrast to the anxiogenic effect observed in the VH, neither TFMPP nor MK-212 significantly changed anxiety measures when microinjected into the dorsal hippocampus. These results suggest that activation of 5-HT2C postsynaptic receptors located in the ventral, but not in the dorsal, hippocampus play an important role in anxiety triggered by the elevated plus-maze test.

Animals↗

Three types of immunotherapics against pythiosis insidiosi developed and evaluated.

Pythiosis is a granulomatous disease of horses, cattle, dogs, cats and humans identified in tropical and subtropical areas and caused by Pythium insidiosum, a zoosporic fungus. Experimental models of pythiosis in naturally infected species have not yet been reported but, rabbits may be inoculated with zoospores as an experimental model for studying the disease. The present study evaluates the efficacy of three different of immunotherapics in the rabbit model. Approximately 17500 zoospores of oomycete P. insidiosum (CBS 101555 strain) were inoculated in each animal to generate the disease. Immunotherapics were produced from vortexed or sonicated cultures of the same strain. Four groups of five animals were employed: group 1, placebo; group 2, sonicated immunotherapic; group 3, mixed immunotherapic; and group 4, vortexed immunotherapic. All rabbits were inoculated with viable zoospores one month before administration of the immunotherapics. Eight doses of immunotherapic or placebo were used in each animal with a 14 day interval between injections. Rabbits receiving the vortexed immunotherapic were most effectively protected (P<0.05), showing a decrease in the area of coastal nodules due to Pythiosis insidiosum by 71.8% after 26 weeks of evaluation. Moreover, two animals in this group showed complete remission of the infection at the end of the 26 weeks. In contrast to these findings, rabbits given the sonicated immunotherapic did not show any protection and had an increase of 211.8% in the size of lesions. This failure of sonicated immunotherapic may reflect denaturation of protective antigens due to the sonication method.

Animals↗

Agalactia in mares fed with grain contaminated with Claviceps purpurea.

This article reports an outbreak of intoxication of female horses with Claviceps purpurea in southern Brazil. The outbreak affected twelve pregnant mares which were fed with black oat (Avena strigosa) during the pre-delivery period. Underdevelopment of the mammary gland in the pre-delivery period resulting in post-delivery agalactia was the most pronounced finding. These mares delivered weak and unviable foals, which showed no suckling reflex and died within a few hours of birth. Laboratory analysis of oat samples fed to the animals resulted in the identification of Claviceps purpurea sclerotia. The fungus was identified in 0.22% of the examined seeds.

Animals↗

First isolation of Candida dubliniensis in Rio Grande do Sul, Brazil.

Candida dubliniensis is a newly recognized species closely phylogenetically related to Candida albicans and is commonly associated with oral candidiasis in human immunodeficiency virus-positive patients. In this paper we report the isolation of three strains of C. dubliniensis, from AIDS patients, in the state of Rio Grande do Sul (Brazil). The phenotypic identification was based on germ tube emission, abundant production of chlamydospores, assimilation of sucrose but not of xylose and the inability to grow at 42 degrees C. Randomly amplified polymorphic DNA (RAPD) analysis and genomic DNA sequencing confirmed the distinct genetic nature C. dubliniensis. Topics related to the epidemiology, isolation, phenotypical and genotypical identification of C. dubliniensis are also discussed.

AIDS-Related Opportunistic Infections↗

Isolation of Prothoteca zopfii from a case of bovine mastitis in Brazil.

The isolation of Prothoteca zopfii, an algae lacking chlorophyll, from bovine mastitic milk, is described herein. The isolation was performed on 8% sheep blood agar, following incubation at 37 circC for 48 h. Based on biochemical tests, susceptibility to clotrimazole, and light and electron microscopic observation of cellular morphology the algae was identified as P. zopfii. The affected animal did not improve following treatment and had to be eliminated.

Animals↗

Acremonium kiliense peritonitis complicating continuous ambulatory peritoneal dialysis: report of two cases.

Two cases of peritonitis caused by Acremonium kiliense in patients receiving a continuous ambulatory peritoneal dialysis treatment are reported. Diagnosis was established by direct examination and cultures of dialysis effluent, secretion of catheter-exit-site and from the tip of the catheter. Management of fungal peritonitis includes catheter removal, since in this infection the result of systemic antifungal therapy is inconsistent.

Acremonium↗

Cutaneous zygomycosis caused by Absidia corymbifera in a leukemic patient.

A case of cutaneous zygomycosis caused by Absidia corymbifera in a leukemic patient submitted to chemotherapy is reported. The lesion was located on the little finger of the right hand and probably resulted from a latent osteomyelitis. It progressed to form extensive necrotic area. No systemic infection was detected and the lesion did not appear to be associated with any trauma.

Adult↗

Curvularia lunata peritonitis complicating peritoneal dialysis.

A case of peritonitis due to Curvularia lunata during continuous ambulatory peritoneal dialysis is reported. Diagnosis was established by culture of dialysis effluent and peritoneal exudate, and was also confirmed through histological examination.

Diabetes Complications↗

The second case of peritonitis due to Histoplasma capsulatum during continuous ambulatory peritoneal dialysis in Brazil.

This paper reports a case of infection due to Histoplasma capsulatum apparently restricted to the peritoneum in a woman submitted to continuous ambulatory peritoneal dialysis (CAPD). Diagnosis was established by direct examination and culture of dialysis effluent. Although the state of Rio Grande do Sul, the southernmost in Brazil, is not considered a region of high endemicity for histoplasmosis, this is the second case of infection occurring in a patient during CAPD.

Brazil↗

Nocardia asteroides peritonitis during continuous ambulatory peritoneal dialysis.

This paper reports a case of peritonitis by Nocardia asteroides during continuous ambulatory peritoneal dialysis in a man who had systemic lupus erythematous and chronic renal failure. Diagnosis was established by microscopic examination (Gram and Kinyoun) and culture of centrifuged dialysis fluid and the patient was treated with Trimethoprim-Sulfamethoxazole by intraperitoneal route.

Adult↗

[Human dermatomycoses in the interior of Rio Grande do Sul in the period of 1988-1992].

The relative frequency of the dermatophytes in the central region of Rio Grande do Sul, Brazil, have changed during a survey carried out from 1988-1992. The frequency of the antropophilic species T. rubrum, T. mentagrophytes var. interdigitale and E. floccosum have decreased in comparison with the zoophilic species M. canis and T. mentagrophytes var. mentagrophytes. The relationship host/parasite and the low rate growth of dermatophytes in culture are discussed.

Adolescent↗