Marcia Dias

Hepatitis B virus infection profile in hemodialysis patients in Central Brazil: prevalence, risk factors, and genotypes

Hemodialysis patients are at high risk for hepatitis B virus (HBV) infection. A survey was conducted in the hemodialysis population of the state of Goiás, Central Brazil, aiming to assess the prevalence of HBV infection, to analyse associated risk factors, and also to investigate HBV genotypes distribution. A total of 1095 patients were interviewed in 15 dialysis units. Serum samples were screened for HBV serological markers by enzyme-linked immunosorbent assay. Hepatitis B surface antigen (HBsAg) positive samples were tested for HBV DNA by polymerase chain reaction and genotyped by restriction fragment length polymorphism. Global HBV infection prevalence was 29.8% (95% CI: 27.1-32.5). Multivariate analysis of risk factors showed that male gender, length of time on hemodialysis, and blood transfusion before 1993 were associated with HBV positivity. HBV DNA was detected in 65.4% (17/26) of the HBsAg-positive samples. Thirteen of 17 HBV DNA positive samples were genotyped. Genotype D (61.5%) was predominant, followed by A (30.8%), while genotype F was detected in only one (7.7%) sample.

Decline of hepatitis C infection in hemodialysis patients in Central Brazil: a ten years of surveillance

Hepatitis C virus (HCV) has been a significant problem for hemodialysis patients. However this infection has declined in regions where the screening for anti-HCV in blood banks and hemodialysis-specific infection control measures were adopted. In Brazil, these measures were implemented in 1993 and 1996, respectively. In addition, all studied units have implemented isolation of anti-HCV positive patients since 2000. In order to evaluate the impact of these policies in the HCV infection prevalence, accumulated incidence, and risk factors in hemodialysis population of Goiânia City, Central Brazil, all patients were interviewed and serum samples tested for HCV antibodies in 1993, 1996, 1999, and 2002. In the first six years (1993-1999), anti-HCV prevalence increased from 28.2 to 37.2%, however a b decrease in positivity was detected between 1999 and 2002 (37.8 vs 16.5%) when the measures were fully implemented. Also, a decrease of the anti-HCV accumulated incidence in cohorts of susceptible individuals during 1993-2002 (71%), 1996-2002 (34.2%), and 1999-2002 (11.7%) was found. Analysis of risk factors showed that length of time on hemodialysis, blood transfusion before screening for anti-HCV and treatment in multiple units were statistically associated with anti-HCV (p < 0.05). Our study showed a significant decline of hepatitis C infection in hemodialysis patients of Central Brazil, gratifying the importance of public health strategies for control and prevention of hepatitis C in the hemodialysis units.

Hepatitis B and C in the hemodialysis unit of Tocantins, Brazil: serological and molecular profiles

A survey was conducted in the hemodialysis population of the state of Tocantins, Brazil, aiming to assess the prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections, to analyze associated risk factors, and also to investigate these viruses genotypes distribution. During January and March 2001, all patients (n = 100) were interviewed at the unique dialysis unit in Tocantins. Blood samples were collected and serum samples were screened for HBV serological markers. Hepatitis B surface antigen positive samples were tested for HBV DNA. All samples were also tested for anti-HCV antibodies and HCV RNA. An overall prevalence of 45% was found for HBV infection (4% were HBsAg/anti-HBc positive, 2% were anti-HBc only and 39% had anti-HBc/anti-HBs markers). Concerning HCV infection, anti-HCV and HCV RNA were detected in 13% and 14% of the subjects, respectively. Three patients were HCV RNA positive and anti-HCV negative, resulting in an overall HCV prevalence of 16%. Univariate analysis of risk factors showed that only shift and length of tile on hemodialysis were associated with HBV and HCV positivity respectively. Among the four HBsAg-positive samples, HBV DNA was detected in three of them, which were identified as genotype A by restriction fragment length polymorphism (RFLP) analysis. All 14HCV RNA-positive samples were genotyped by INNO-LiPA. Genotypes la and 3a were found in 85% and 15%, respectively. The present data show low HBsAg and HCV prevalence rates. The risk factors associated with HBV and HCV positivity suggest that nosocomial transmission may influence in spreading these viruses in the dialysis unit studied.

Seroepidemiology of hepatitis B virus infection and high rate of response to hepatitis B virus Butang®vaccine in adolescents from low income families in Central Brazil

In order to evaluate the seroepidemiology and response to Butang vaccine in adolescents from low income families in Central Brazil, blood samples of 664 adolescents were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs) markers, and multiple logistical regression analysis was carried out to determine variables associated with hepatitis B virus (HBV) infection markers. further, three 20 microg Butang vaccine doses were offered to all susceptible individuals (n = 304). Among those who accepted them (n = 182), the seroresponse was evaluated in 170 individuals by quantitative anti-HBs. an overall hbv prevalence of 5.9% was found: four adolescents were HBsAg positive, 24 were anti-HBc, anti-HBs-reactive, and 11 were anti-HBc only. The analyse of risk factors showed that age 16-19 years, place of birth outside Goiás, school B and body piercing were statistically associated with HBV infection markers (p < 0.05). All 170 adolescents responded to Butang, and a geometric mean titer (gmt) of 4344 mUI/ml was obtained. these results reinforce the importance of hepatitis b vaccine in adolescents despite of the hbv regional endemicity, and suggest that three doses of 20 microg of the Butang should guarantee protective anti-hbs levels to individuals at a critical time for hepatitis b acquiring such as latter adolescence and adulthood.

GB virus C/hepatitis G virus infection in dialysis patients and kidney transplant recipients in central Brazil

In order to investigate the prevalence of GB virus C (GBV-C)/hepatitis G virus (HGV) infection in dialysis patients and kidney transplant recipients in Central Brazil and also to analyze the virus genotypes distribution, a total of 123 patients including 98 on hemodialysis, 13 on continuous ambulatory peritoneal dialysis treatment, and 12 who received kidney transplantation were interviewed in one unit of dialysis treatment in Goiania city. Blood samples were collected and serum samples tested for GBV-C/HGV RNA by polymerase chain reaction. Genotypes were determined by restriction fragment length polymorphism (RFLP) analysis. Eighteen samples were GBV-C/HGV RNA-positive, resulting in an overall prevalence of 14.6% (95% CI: 9.2-21.7). A high positivity for GBV-C/HGV RNA was observed in patients who had received kidney transplant (16.7%), followed by those on hemodialysis (15.3%), and peritoneal dialysis (7.7%). RFLP analysis revealed the presence of genotypes 1, 2, and 3 of GBV-C/HGV; more precisely, 9 (50%) samples were found belonging to the 2b subtype, 4 (22%) to the 2a subtype, 3 (17%) to genotype 1, and 2 (11%) to genotype 3. The present data indicate an intermediate prevalence of GBV-C/HGV infection among dialysis patients and kidney transplant recipients in Central Brazil. Genotype 2 (subtype 2b) seems to be the most prevalent GBV-C/HGV genotype in our region.

Parâmetros ruminais, balanço de compostos nitrogenados e produção microbiana de vacas leiteiras alimentadas com soja e seus subprodutos

The objective of this study was to assess the variation in the pH, ruminal ammonia, nitrogen compound balance (BN) and microbial synthesis (Nmic) of 12 Holstein cows distributed in three 4 × 4 Latin squares, fed diets containing soybeans in different forms: only soybean meal (SM - control diet), raw soybeans (RS), toasted soybeans (RST) and soybean meal plus 5% urea (SMU), using corn silage as bulk. The microbial protein synthesis was estimated using the purine derivatives in the urine and the milk. Blood samples and spot urine were collected, approximately four hours after the morning meals. There was effect of the diets on the urine volume (UV) and the urea excretion in the urine (UEU). The smallest urine volume (18.84 L) was observed with soybean meal + urea. Urea excretions in the urine were similar among the diets containing raw soybean (532.98 mg/kgPV) and toasted soybean (524.41 mg/kgPV) and differed between the soybean meal (561.56 mg/kgPV) and soybean meal + urea (575.71 mg/kgPV). The way of supplying soybean did not affect the nitrogen balance or the ureic nitrogen concentrations in the Plasma (NUP), but they had a significant effect on the ureic nitrogen in the milk (NUL) whose greatest mean was obtained with raw soybean (15.66 mg/dL). The means of alantoina in the urine (416.45 mmol/dia), milk (12.78 mmol/dia), total purine derivatives (468.30 mmol/dia), microbial protein synthesis (287.33 g/dia) and the efficiency of the microbial synthesis (133.06), expressed in g of CP/kg of consumed TNT did not differ among the diets. The diets tested did not the nitrogen balance or the microbial production, but the addition of raw soybean grains increased nitrogen levels in the milk.

Zeólita na dieta de bovinos de corte

We evaluated the effect of the inclusion of zeolite in the diet of beef cattle on the ruminal digestibility, total and partial production of nitrogen, microbial efficiency and blood characteristics. Treatments based on the dietary dry matter (DM) were: 0%, 0.75%, 1.5%, 2.25% and 3.0% of zeolite. We used five crossbred steers fistulated in the rumen and abomasum, fed corn silage and concentrate, representing 65% forage and 35% concentrate. The design was a 5x5 latin square with five periods of 15 days. The animals received 15g of titanium dioxide (TiO2) from the third to the 12th day of each period. A significant effect (P<0.05) on the daily consumption (kg/day) of crude protein (CP) was observed (P<0.05) for DM intake and neutral detergent fiber corrected for ash and protein (NDFap) expressed in g/kg. The total digestibility of total digestible nutrients (TDN) was influenced by treatments (P<0.05). Ruminal digestibility of non-fiber carbohydrates (NFC) was affected quadratically (P<0.05) as well as intestinal CP and NFC. Intake and fecal excretion of nitrogen (g/day) were affected linearly (P<0.05) by adding zeolite. It was concluded that the addition of zeolite in the diet, while increasing the intake of DM and NDF, did not improve the use of urea in the diet of beef cattle.

Técnicas para estimativa da digestibilidade e produção microbiana em bovinos

The objective was to evaluate the estimate of digestion and microbial production by using indigestible neutral and acid detergent fiber (iNDF and iADF respectively) and to compare microbial production estimated by purine bases in the omasum and urinary excretion of purine derivatives. Four rumen and ileum fistulated Holstein-Zebu heifers with average initial 220 kg LW was maintained in confined regime fed diet based on Tifton (Cynodon spp.) hay, offered ad libitum and 1kg of concentrate (27% CP). The experiment lasted 60 days: seven for adaptation to the diet (before the first period); three 15 day-experimental periods and four days of interval among periods. Total collection of feces, omasum and ileum digesta sampling, rumen contents sampling for bacterial isolation and sampling of urine spot were performed. For the determination of omasal and ileal flow, iNDF and iADF were used as markers. Rumen enviromment was favourable for microbial growth, showing pH values between 6.7 to 6.9 and NH3-N values from 10.3 to 14.1 mg/dL. Recovery of iADF did not differ from 100% and produced similar estimation for fecal excretion and total digestion, when compared to total fecal sampling, differently of iNDF. Estimation of microbial production through quantification of purine derivative in urine spot samples was not similar to the obtained by invasive procedure through omasal microbial matter. Thus, it is recommended to use iADF for partial and total digestion estimation and urinary excretion of purine derivative for microbial production estimation.

Biochemical composition of the hoof capsule of buffaloes and its influence on hoof quality

O presente estudo objetivou estabelecer os parâmetros bioquimicos da muralha abaxial, muralha dorsal e sola do casco dos digitos toracico medial e pelvico lateral dos bubalinos. Foram realizadas analises bioquimicas destrutivas das amostras dos cascos para se obterem os teores de materia seca (MS), materia mineral (MM), materia orgânica (MO), proteina bruta (PB) e extrato etereo (EE). As analises bioquimicas nao destrutivas foram empregadas para se avaliarem os niveis de enxofre (S), calcio (Ca), potassio (K), fosforo (P), zinco (Zn) e cobre (Cu). Concluiu-se que os parâmetros materia seca, materia mineral, materia orgânica, proteina bruta e extrato etereo do estojo corneo dos digitos de bubalinos podem ser definidos por analises bioquimicas destrutivas e nao destrutivas. Os maiores valores dos elementos minerais estao concentrados nos digitos que suportam o maior peso do animal, sugerindo que existe uma relacao positiva entre esses parâmetros. Alem disso, este estudo revelou que as maiores concentracoes de MS, PB e minerais como, K, Zn e Cu estao nos digitos que carregam o maior peso de massa corporal, o que indica que ha uma correlacao positiva entre os parâmetros acima referidos, resistencia e crescimento do estojo corneo dos digitos. Em relacao ao elemento de S, este estudo demonstrou que a sua maior concentracao situa-se nos digitos laterais dos membros pelvicos.