Clinical, demographic and epidemiological characteristics of patients with hepatitis B followed at a university hospital in southeastern Brazil: predominance of HBeAg negative cases

INTRODUCTION: Hepatitis B is common in Brazil, although there are regional differences regarding the degree of endemicity, the most frequent forms of transmission and the presence of different evolutive stages of chronic disease. The present study aimed to determine the clinical, demographic and epidemiological characteristics of patients chronically infected with hepatitis B virus (HBV) residing in the Ribeirão Preto region, southeastern Brazil. METHODS: A total of 529 medical records of individuals with HBV monoinfection were reviewed. RESULTS: More than 60% of the subjects were males, with a mean age of 38 years-old. The HBeAg-negative serological pattern was verified in 84.4% of the patients, among whom the risk of vertical/intrafamily transmission was 43.2% (p = 0.02). The consumption of alcohol in amounts exceeding 20g a day was observed in 21.3% of the subjects and was more frequent among men (33%) (p < 0.001). Among patients with cirrhosis, 54.1% were alcohol abusers (p = 0.04), all of them males. The presence of cirrhosis was more frequent in the HBeAg-positive group (24.4%) than in the HBeAg-negative group (10.2%) (p < 0.001). CONCLUSIONS: High proportions of HBV-infected subjects with an HBeAg-negative pattern were observed, with a higher risk of vertical/intrafamily transmission. Alcohol abuse was associated with male subjects and with cirrhosis of the liver in this group. A tendency toward an increase in the number of HBeAg-negative cases was observed over time.

Antibody levels in children after 10 years of vaccination against hepatitis B: a brazilian community-based study

INTRODUCTION: It is known that the hepatitis B (HB) vaccine is effective, but it is alarming that sudden drops of antibody levels may coincide with the onset of adolescence. METHODS: Antibody levels against HB vaccine surface antigen (anti-HBs) and HB vaccine core antigen (anti-HBc) were measured on the blood samples of children with a mean age of 11.4 years. RESULTS: About 54.8% had protective levels of anti-HBs. Of those who were anti-HBc-positive (4.4%), an average of 218.4 anti-HBs mIU/mL was found. CONCLUSIONS: Immunological protection was found in the majority of children. However, more studies are needed to elucidate the heritability of nonresponders and establish strategies against such events.

Epidemiology of the viral hepatitis B and C in female prisoners of Metropolitan Regional Prison Complex in the State of Goiás, Central Brazil

INTRODUCTION: Little information regarding hepatitis B virus (HBV) and hepatitis C virus (HCV) infections among Brazilian female prisoners exists. This study investigated the prevalence and risk factors associated with HBV and HCV infections and identified viral genotypes among female prisoners in Goiás, Central Brazil. METHODS: Women incarcerated in the largest prison in the State of Goiás were invited to participate in the study. All female prisoners were interviewed and tested for the detection of hepatitis B surface antigen (HBsAg), antibodies against HBsAg (anti-HBs), against hepatitis B core antigen (anti-HBc), and antibody against HCV (anti-HCV) by ELISA. HBsAg and anti-HCV positive samples were tested for HBV DNA and HCV RNA and genotyped, respectively. RESULTS: Participants (n=148; 98.6%) completed the study with an overall HBV prevalence of 18.9%. Age >30 years, a low education level, sex with a sexually transmitted diseases carrier, and a male sexual partner serving in the same penitentiary were associated with HBV infections. Only 24% of the women were anti-HBs positive suggesting previous HBV vaccination. Nine female prisoners (6.1%) were anti-HCV positive. Age >40 years, injecting drug use and length of incarceration were statistically associated with anti-HCV antibodies. Five samples were HCV RNA positive and classified as genotypes 1 (subtypes 1a; n=3 and 1b; n=1) and 3 (subtype 3a; n=1). The HBsAg-reactive sample was HBV DNA positive and genotype A. CONCLUSIONS: These findings highlight the necessity of public policies to control hepatitis B and C infections and emphasize the importance of hepatitis B vaccination in prison environments.

Biomass production and essential oil yield from leaves, fine stems and resprouts using pruning the crown of Aniba canelilla (H.B.K.) (Lauraceae) in the Central Amazon

Aniba canelilla (H.B.K.) Mez. is a tree species from Amazon that produces essential oil. The oil extraction from its leaves and stems can be an alternative way to avoid the tree cutting for production of essential oil. The aim of this study was to analyse factors that may influence the essential oil production and the biomass of resprouts after pruning the leaves and stems of A. canelilla trees. The tree crowns were pruned in the wet season and after nine months the leaves and stems of the remaining crown and the resprouts were collected, in the dry season. The results showed that the essential oil yield and chemical composition differed among the stems, leaves and resprouts. The stems' essential oil production differed between the seasons and had a higher production in the resprouting stems than the old stems of the remaining crown. The production of essential oil and leaf biomass of resprouts were differently related to the canopy openness, indicating that light increases the production of the essential oil and decreases the biomass of resprouting leaves. This study revealed that plant organs differ in their essential oil production and that the canopy openness must be taken into account when pruning the A. canelilla tree crown in order to achieve higher oil productivity.

Endoparasite fauna of Brycon amazonicus and B. melanopterus(Characidae, Bryconinae) from Negro and Solimões rivers, Amazon, Brazil

ABSTRACTCongeneric host species present similar biological and behavioral aspects, what may favor the presence of a similar parasite fauna. The aim of the present study was to compare the composition and structure of the parasite community from congeneric species, Brycon amazonicus and B. melanopterus, collected on the Negro and Solimões Rivers. The fish internal organs were longitudinally opened and analyzed under stereomicroscope. The examination revealed that B. amazonicuswas parasitized by Procamallanus(Spirocamallanus) inopinatus(26.7% and 35.5%), Contracaecum type 2 (10% and 16.13%) and Rhabdochona acuminata(0% and 3.23%), prevalence values for Negro and Solimões River, respectively. The analysis of B. melanopterus, a fish species found only in the Solimões River, revealed P.(S.) inopinatus(33.3%), Contracaecum type 1 (60%) and R. acuminata(3.34%). These results indicate that the taxonomic proximity of the hosts was a stronger influence on the parasite species than external host environment.

Atividade antibacteriana do Aspergillus niger van Tieghem, 1867; pesquisas em 14 amostras da National Collection of Type Cultures (M. R. C.)

1. Pesquisamos a atividade antibacteriana em 14 amostras de Aspergillus niger da National Collection of Type Cultures. 2. Em meio de Raulin e Mosseray, sete amostras apresentaram atividade total, nunca superior a 1:10, contra Staphylococcus aureus nº 553, sendo que as amostras 1.161 e 2.390 permaneceram ativas por mais de 40 dias. 3. A utilização do meio de Czapek-Dox com 5% de "corn-steep" não melhorou os resultados obtidos com o meio de Raulin e Mosseray. 4. No meio de levedo peptonado, todas as amostras apresentaram-se inativas.

Competitive interactions between species of fresh-water snails: I. Laboratory. IC. Comparative survival of Biomphalaria glabrata and B. Straminea kept out of water

Biomphalaria glabrata and B. straminea were submitted to an out-door laboratory experiment for testing their comparative ability to resist desiccation. Results have shown that B. straminea is significantly higher resistant than B. glabrata. After five months under such distressing condition the survival ratios were: B. glabrata 8.1 per cent and B. straminea 18.4 per cent.

Competitive displacement of Biomphalaria glabrata by B. straminea

Data on the interaction between populations of closely related species of Biomphalaria, B. glabrata and B. straminea, are presented in the current paper. Laboratory and field observations and experiments have shown that B. straminea has competitive advantages over B. glabrata.

Fecundity of Biomphalaria straminea and B. glabrata in the laboratory: a twelve-month comparative study

In the present comparative study a Biomphalaria straminea sample from Picos (Piauí) showed expressive advantages related to fecundity over a B. glabrata sample from Belo Horizonte (Minas Gerais) such as: higher egg-mass production in 10 out of 12 months of study; higher egg production in all months of study; higher egg per egg-mass ratio in 11 out of 12 months of study; 66% of the egg-masses containing more than 20 eggs while in B. glabrata 70% of the egg-masses showed less than 20 eggs; three times less empty egg capsules than B. glabrata; attainning maximum fecundity in half the time required by B. glabrata. Mortality however was higher and sooner in B. straminea, suggesting higher semelparity in this species than in B. glabrata, a possibility that requires confirmation through long-term studies with other samples of both species. This first finding of a B. straminea sample more fecund than B. glabrata is discussed in relation to other data from the literature, and some recommendations are made on the quantification of fecundity of planorbid snails.

A low stringency polymerase chain reaction approach to the identification of Biomphalaria glabrata and B. tenagophila, intermediate snail hosts of Schistosoma mansoni in Brazil

The low stringency-polymerase chain reaction (LS-PCR) with a pair of specific primers for the amplification of the 18S rRNA gene was evaluated as a means of differentiating between the two Schistosoma mansoni intermediate host species in Brazil: Biomphalaria glabrata and B. tenagophila. Individual snails obtained from different states of Brazil were used and the amplification patterns obtained showed a high degree of genetic variability in these species. Nevertheless, 4 and 3 clearly defined specific diagnostic bands was observed in individuals from B. glabrata and B. tenagophila respectively. The detection of snail specific diagnostic bands suggests the possibility of reliable species differentiation at the DNA level using LS-PCR.

Prevalence of antibodies to hepatitis B core antigen in blood donors in the middle west region of Brazil

The prevalence of antibodies to hepatitis B core antigen in 552 prime blood donors was of 9.4%. The majority (71.2%) has antibodies to hepatitis B surface antigen. The hepatitis B surface antigen was present in 0.7%, all of them antibodies to hepatitis B core antigen positive.

Longitudinal Study on the Natural Infection of Biomphalaria straminea and B. glabrata by Schistosoma mansoni in an Endemic Area of Schistosomiasis in Pernambuco, Brazil

The abundance of snail hosts and the rates of infection with Schistosoma mansoni were monitored monthly for four years in two representative localities subjected to repeated chemotherapy of infected persons. Snail abundance varied from 1.0 to 4.4 collected per person/minute/station for Biomphalaria straminea and from 0.1 to 7.0 for B. glabrata. Infection rates of snails in nature varied from 0% to 15% for the former and from 0% to 70% for the latter species. Human infection increased from 35.5% to 61.9% in the locality occupied by B. straminea, and decreased from 40.3% to 20.8% in that occupied by B. glabrata. No relationship could be detected between human infection and the snail variables. Despite seasonal variations, natural infection persisted throughout the monitoring period in both snail species. It reached remarkably high levels in B. straminea when compared to those obtained by other authors probably because of differences in methodology. It is recommended that longitudinal studies should be carried out focally and periodically to avoid underestimating the prevalence of schistosome infection in snails.

Comparative immunological recognition of proteins from New Guinea "C" dengue virus type 2 prototype and from a dengue virus type 2 strain isolated in the State of Rio de Janeiro, Brazil

The protein profiles of the New Guinea "C" dengue virus type 2 (DENV-2)prototype and those of a Brazilian DENV-2 isolated in the State of Rio de Janeiro in 1995 were compared. SDS-PAGE analysis showed that the virus from Rio de Janeiro expresses NS5 (93.0 kDa), NS3 (66.8 kDa) E (62.4 kDa) and NS1 (41.2 kDa) proteins differently from the New Guinea "C" virus. The immunoblot revealed specificity and antigenicity for the NS3 protein from DENV-2 Rio de Janeiro mainly in primary infections, convalescent cases, and in secondary infections in both cases and only antigenicity for E and NS1 proteins for both viruses in primary and secondary infections.