Adenovirus, enterovirus and thermotolerant coliforms in recreational waters from Lake Guaíba beaches, Porto Alegre, Brazil

In the present study, molecular detection of human adenoviruses (HAdV) and enteroviruses (EV) was performed in surface water samples collected from beaches Ipanema and Lami, located on the shores of Lake Guaíba, city of Porto Alegre, RS, southern Brazil. Furthermore, water safety was evaluated by counting thermotolerant coliforms (TC), following local government regulations. A total of 36 samples were collected monthly from six different sites along the beaches. Viral genomes were found in 30 (83.3%) samples. The higher detection rate was observed for HAdV (77.8%), followed by EV (22.2%). Although low concentrations of TC have been found, the occurrence of viral genomes in water samples was frequent and may pose a potential risk of infection for people bathing in these beaches.

Growth of Paecilomyces variotii in B0 (diesel), B100 (biodiesel) and B7 (blend), degradation and molecular detection

The introduction of biodiesel to diesel may allow the fuel to be more susceptible to microorganism growth, especially during incorrect storage. To evaluate the effect of adding biodiesel in pure diesel on the growth of Paecilomyces variotii, microcosms containing pure diesel (B0), blend diesel/biodiesel (B7) and pure biodiesel (B100) were used. In microcosm with minimal mineral medium and B0, B7 or B100, after 60 days, the biomass (dry weight) formed at interface oil-water in B7 and B100 was significantly higher when compared to that of B0. Infrared analysis showed reduction of the carbonile fraction in B7 and B100 suggesting formation of intermediate compounds in B7. To monitor possible contamination of fuel storage tank by P. variotii samples were collected and analysed by specific-PCR assay for detection of P. variotii spores in the aqueous phase. This method was able to detect a minimum of 103 spores ml-1, corresponding to 0.0144 ng µl-1 of DNA. Specificity was tested against Aspergillus fumigatus and Pseudallescheria boydii.

The biology of malarial parasite in the mosquito--a review

The purpose of this review is to summarize the biology of Plasmodium in the mosquito including recent data to contribute to better understanding of the developmental interaction between mosquito and malarial parasite. The entire sporogonic cycle is discussed taking into consideration different parasite/vector interactions and factors affecting parasite development to the mosquito.

Kinetics of expression of two major Plasmodium berghei antigens in the mosquito vector, Anopheles stephensi

Expression of a 21 kDa determinant (Pbs21), first detected on the surface of ookinetes, and of the circumsporozoite protein (CSP) was studied by immunofluorescence and Western blots during the developmental cycle of Plasmodium berghei in the mosquito Anopheles stephensi. The expression of Pbs21 was predominantly localised on the ookinete surface one day after the infectious blood meal, and thereafter reactivity declined to a minimum on days 2 and 3, the time of onset of oocyst development. A gradual increase in fluorescence was observed on the oocysts from day 6 that was retained until day 17 post-infection. In contrast, sporozoites released from oocysts or salivary glands showed little or no antibody labelling with anti-Pbs21. Circumsporozoite protein was not detectable in any midgut preparations until 5-6 days after feeding, when reactivity was observed against immature oocysts. Expression then continued and increased throughout oocyst and sporozoite development. Western blots confirmed that Pbs21 was expressed minimally during the oocyst development but was not detectable in sporozoites. Co-localisation of anti-Pbs21 and anti-CSP monoclonal antibodies to the 50 kDa and 60 kDa bands in Western blots of sporozoite suggests immunological cross-reactivity between the CSP and the anti-21 kDa antibodies.

[Behavior of the indirect immunofluorescence reaction and of cerebrospinal fluid parameters in neurocysticercosis]

Cerebrospinal fluid from 53 patients with clinical evidence of neurocysticercosis and 11 who suffered from several diseases were studied to evaluate the behaviour of indirect immunofluorescence test and some parameters of routine analysis. In neurocysticercosis there were pleocytosis in 88.7% of cases, eosinophilorrachia in 60.3%, hyperproteinorrachia in 71.7% and hypoglucorrachia in 13.2%. The indirect immunofluorescence test was positive in 79.2% of cases but false-positive results were found when the samples showed xanthochromia or erythrocyte contamination. The authors discuss their results in comparison with those in literature and conclude that the immunofluorescent test is sensitive and useful in diagnosis of neurocysticercosis, except when the interferents previously mentioned are present.

[Identification of aminoacidopathies using thin layer chromatography of urine]

The aminoacidopathies, inborn errors of aminoacids metabolism, are rare pathological conditions that have mental retardation as secondarty cause. Using TLC with cellulose as adsorvent and using specific solvents and developer, we can obtain early diagnosis of a great number of those biochemical deviations. The authors based themselves in Ersser's publications to effect this research, now in its initial phase. The author's principal aim is to transform the semi-quantitative method into a quantitative one and to early diagnose the metabolic errors of aminoacids.