McCoy cell line as a possible model containing CD4+ receptors for the study of HIV-1 replication

Several studies have recently shown the use of recombinant rabies virus as potential vector-viral vaccine for HIV-1. The sequence homology between gp 120 and rabies virus glycoprotein has been reported. The McCoy cell line has therefore been used to show CD4+ or CD4+ like receptors. Samples of HIV-1 were isolated, when plasma of HIV-1 positive patients was inoculated in the McCoy cell line. The virus infection was then studied during successive virus passages. The proteins released in the extra cellular medium were checked for protein activity, by exposure to SDS Electrophoresis and blotting to nitro-cellulose filter, then reacting with sera of HIV positive and negative patients. Successive passages were performed, and showed viral replication, membrane permeabilization, the syncytium formation, and the cellular lysis (cytopathic effect). Flow cytometry analysis shows clear evidence that CD4+ receptors are present in this cell line, which enhances the likelihood of easy isolation and replication of HIV. The results observed allow the use of this cell line as a possible model for isolating HIV, as well as for carrying out studies of the dynamics of viral infection in several situations, including exposure to drugs in pharmacological studies, and possibly studies and analyses of the immune response in vaccine therapies.

USE OF MUELLER-HINTON BROTH AND AGAR IN THE GERM TUBE TEST

Candida albicans is often isolated from clinical samples, thus its presumptive differentiation from other species of the same genus can be based on its ability to form the germ tube in human serum. Nevertheless, there are two other species that share this characteristic: C. dubliniensis and C. africana. The aim of this study was to compare four different substrates to perform the germ tube (GT) test. The Candida spp. isolates were identified using a manual system (135 C. albicans, 24 C. tropicalis and one C. dubliniensis). The germ tube test was performed with fresh, previously frozen serum and Mueller-Hinton (MH) broth and agar. GT was observed in 96% (130/136) of the isolates through the fresh serum technique, 94% (128/136) through previously frozen serum, 92% (125/136) in MH agar, and 90% (122/136) in MH broth. The sensitivity of each test was higher than 90%, with 100% specificity. Both the MH agar and broth were able to identify the true positives, and false positives were not found. However, some C. albicans isolates were not identified. MH agar and broth may be used in laboratory for the rapid presumptive identification of C. albicans, as an alternative method for germ tube test.

Livros on-line da área médica

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Establishment of HTLV-I-infected cell lines from peripheral blood mononuclear cells of Brazilian patients

To investigate epidemiological and pathogenetic features of HTLV-I infection, a cohort of carriers has been followed at the USP Teaching Hospital since 1991. This study describes the establishment of cell lines from peripheral blood mononuclear cells (PBMC) of infected subjects. Ex vivo PBMC were cultured with those from a seronegative donor and morphologic evidence of cell transformation was obtained after 90 days with detection of multinucleated cells exhibiting cerebriform nuclei. Integration of HTLV-I proviral DNA and expression of viral antigens was demonstrated in culture by PCR and immunofluorescence. Cell lines were maintained for 240 days, gradually weaned from exogenous IL-2. Immunophenotyping of cell lines on flow cytometry yielded evidence of cell activation. Establishment of HTLV-I-infected cell lines from ex vivo PBMC is feasible and may be useful for studies on lymphocyte phenotypic changes and on mechanisms of HTLV-induced cell proliferation. Moreover they may be used with diagnostic purposes in immunofluorescence tests.

Assessment of integration of the leprosy program into primary health care in Aracaju, state of Sergipe, Brazil

INTRODUCTION: The aim of this study was to assess the epidemiological and operational characteristics of the Leprosy Program before and after its integration into the Primary healthcare Services of the municipality of Aracaju-Sergipe, Brazil. METHODS: Data were drawn from the national database. The study periods were divided into preintegration (1996-2000) and postintegration (2001-2007). Annual rates of epidemiological detection were calculated. Frequency data on clinico-epidemiological variables of cases detected and treated for the two periods were compared using the Chi-squared (χ2) test adopting a 5% level of significance. RESULTS: Rates of detection overall, and in subjects younger than 15 years, were greater for the postintegration period and were higher than rates recorded for Brazil as a whole during the same periods. A total of 780 and 1,469 cases were registered during the preintegration and postintegration periods, respectively. Observations for the postintegration period were as follows: I) a higher proportion of cases with disability grade assessed at diagnosis, with increase of 60.9% to 78.8% (p < 0.001), and at end of treatment, from 41.4% to 44.4% (p < 0.023); II) an increase in proportion of cases detected by contact examination, from 2.1% to 4.1% (p < 0.001); and III) a lower level of treatment default with a decrease from 5.64 to 3.35 (p < 0.008). Only 34% of cases registered from 2001 to 2007 were examined. CONCLUSIONS: The shift observed in rates of detection overall, and in subjects younger than 15 years, during the postintegration period indicate an increased level of health care access. The fall in number of patients abandoning treatment indicates greater adherence to treatment. However, previous shortcomings in key actions, pivotal to attaining the outcomes and impact envisaged for the program, persisted in the postintegration period.

Determination of germ tube, phospholipase, and proteinase production by bloodstream isolates of Candida albicans

Introduction Candida albicans is a commensal and opportunistic agent that causes infection in immunocompromised individuals. Several attributes contribute to the virulence and pathogenicity of this yeast, including the production of germ tubes (GTs) and extracellular hydrolytic enzymes, particularly phospholipase and proteinase. This study aimed to investigate GT production and phospholipase and proteinase activities in bloodstream isolates of C. albicans. Methods One hundred fifty-three C. albicans isolates were obtained from blood samples and analyzed for GT, phospholipase, and proteinase production. The assays were performed in duplicate in egg yolk medium containing bovine serum albumin and human serum. Results Detectable amounts of proteinase were produced by 97% of the isolates, and 78% of the isolates produced phospholipase. GTs were produced by 95% of the isolates. A majority of the isolates exhibited low levels of phospholipase production and high levels of proteinase production. Conclusions Bloodstream isolates of C. albicans produce virulence factors such as GT and hydrolytic enzymes that enable them to cause infection under favorable conditions.

Analysis of the detection coefficient for the association between leprosy and pregnancy in the integration region of Carajas, State of Para, Brazil

Introduction The association between leprosy and pregnancy is currently poorly understood and has been linked to serious clinical consequences. Methods A retrospective study between 2007 and 2009 was performed in the integration region of Carajás, Brazil on a population of pregnant lepers, with non-lepers of ages 12-49 years serving as the reference population. Results Twenty-nine pregnant lepers were studied during the study period. The detection rates (DRs) for the studied association were 4.7 in 2007, 9.4 in 2008, and 4.3 in 2009. Conclusions The Carajás region presented a medium pattern of endemicity during most of the study period, with a high DR found in 2008.

Effects of Rosmarinus officinalis essential oil on germ tube formation by Candida albicans isolated from denture wearers

Introduction The aim of this study was to investigate the effects of Rosmarinus officinalis essential oil on germ tube formation by Candida albicans isolated from denture wearers. Methods Ten C. albicans isolates recovered from denture wearers were tested using 10% fetal bovine serum with or without 4% R. officinalis essential oil. Results The essential oil from R. officinalis completely inhibited germ tube formation in the investigated C. albicans isolates. Conclusions The results demonstrate that the essential oil of R. officinalis modulates C. albicans pathogenicity through its primary virulence factor (i.e., germ tube formation was suppressed).

On line pre-concentration for simultaneous determination of low molecular weight organic acids and inorganic anions in Amazonian river water samples employing ion chromatography with conductivity detection

An ion chromatography procedure, employing an IonPac AC15 concentrator column was used to investigate on line preconcentration for the simultaneous determination of inorganic anions and organic acids in river water. Twelve organic acids and nine inorganic anions were separated without any interference from other compounds and carry-over problems between samples. The injection loop was replaced by a Dionex AC15 concentrator column. The proposed procedure employed an auto-sampler that injected 1.5 ml of sample into a KOH mobile phase, generated by an Eluent Generator, at 1.5 mL min-1, which carried the sample to the chromatographic columns (one guard column, model AG-15, and one analytical column, model AS15, with 250 x 4mm i.d.). The gradient elution concentrations consisted of a 10.0 mmol l-1 KOH solution from 0 to 6.5 min, gradually increased to 45.0 mmol l-1 KOH at 21 min., and immediatelly returned and maintained at the initial concentrations until 24 min. of total run. The compounds were eluted and transported to an electro-conductivity detection cell that was attached to an electrochemical detector. The advantage of using concentrator column was the capability of performing routine simultaneous determinations for ions from 0.01 to 1.0 mg l-1 organic acids (acetate, propionic acid, formic acid, butyric acid, glycolic acid, pyruvate, tartaric acid, phthalic acid, methanesulfonic acid, valeric acid, maleic acid, oxalic acid, chlorate and citric acid) and 0.01 to 5.0 mg l-1 inorganic anions (fluoride, chloride, nitrite, nitrate, bromide, sulfate and phosphate), without extensive sample pretreatment and with an analysis time of only 24 minutes.

Hipometilação do LINE-1 está Associada ao Risco de Doença Cardíaca Coronariana na População Chinesa

Fundamentos: O nível de metilação global do ADN de leucócitos no sangue tem sido associado ao risco de doença arterial coronariana (DAC), com resultados inconsistentes em diferentes populações. Faltam dados semelhantes da população chinesa, onde diferentes fatores genéticos, de estilo de vida e ambientais podem afetar a metilação do ADN e sua relação com o risco de DCC. Objetivos: Analisar se a metilação global está associada ao risco de doença coronariana na população chinesa. Métodos: Foram incluídos um total de 334 casos de DCC e 788 controles saudáveis. A metilação global do ADN de leucócitos de sangue foi estimada por meio da análise das repetições do LINE-1 usando pirosequenciamento de bissulfito. Resultados: Em uma análise inicial restrita aos controles o nível do LINE-1 diminui significativamente com a idade avançada, colesterol total elevado, e diagnóstico de diabetes. Na análise de caso-controle, a redução da metilação do LINE-1 foi associada ao aumento do risco de DCC, tendo a análise por quartil revelado uma odds ratio (IC 95%) de 0,9 (0,6-1,4), 1,9 (1,3-2,9) e 2,3 (1,6 3.5) para o terceiro, segundo e primeiro (o mais baixo) quartil (P da tendência < 0,001), respectivamente, em comparação com o quarto (o mais alto) quartil. A metilação inferior (< mediana) do LINE-1 esteve associada a 2,2 vezes (IC 95% = 1,7-3,0) o aumento de risco de doença coronariana. As estimativas de risco de DCC menores relacionadas com o LINE-1 tenderam a ser mais fortes entre os indivíduos com maior tercil de homocisteína (P interação = 0,042) e naqueles com diagnóstico de hipertensão arterial (P interação = 0,012). Conclusão: A hipometilação do LINE-1 está associada ao risco de doença coronariana na população chinesa. Fatores de risco de DCC potenciais tais como a idade avançada, colesterol total elevado, e diagnóstico de diabetes podem ter impacto na metilação global do ADN, exercendo, portanto, o seu efeito sobre o risco de doença coronariana.

On the current existence of a coccidial line of development in the malaria parasites: a theory

Most opinion favors the origin of the malaria parasites from a coccidial ancestor. It is assumed that whatever the process through which the coccidia differentiated into a Plasmodium this phenomenon very probably occured millions of year ago, and during that differentiation process the original coccidia vanished. Therefore it has never repeated. At the light of some experiments the existence, at the present time, of a coccidial cycle of development in the malaria parasites, is proposed. The conection routes and mechanisms through which the malaria parasite changes to a coccidial life, and the routes in reverse are exposed. Transmission of the malaria-coccidial forms is suggested.

Establishment and Characterization of a Cell Line from the Mosquito Anopheles albimanus (Diptera: Culicidae)

A new cell line designated LSB-AA695BB, was established from embryos of the mosquito Anopheles albimanus. The primary culture was initiated in April, 1995, and the first passage was made 48 days later. Serial subcultures of the cells have been carried through 90 passages from Abril 1995 to February 1996. The cells were grown at 28°C in MK/VP12 medium, supplemented with 20% fetal bovine serum; the pH tolerance ranged between 6.8 to 7.0. The cells have also been adapted to MM/VP12 medium under the same pH, temperature and serum concentration. The majority of the cells were a fibroblast-type. Isozyme characterization showed a pattern similar to that of An. albimanus pupae and adults but distinct from Ae. taeniorhynchus and Ae. albopictus (C6/36) mosquito cell lines. The culture was shown to be free of mycoplasma, bacteria and fungi. Microsporidia contamination of transovarial transmission was controlled with 6.0 mg/ml of albendazole