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.     

Genetic parameters of libido in Brazilian Nellore bulls

Genetic, environmental and phenotypic correlations between libido, testicular measurements, body weight and semen traits were estimated by multiple-trait-restricted maximum likelihood (MTDFREML) under animal models. Reproductive records, collected from 1992 to 1997, of 288 Nellore bulls were used. Estimates of heritability for libido unadjusted, adjusted for scrotal circumference and adjusted for body weight, were 0.34 +/- 0.10, 0.31 +/- 0.10, and 0.19 +/- 0.11, respectively. Genetic correlations between libido and body weight, scrotal circumference, testis length, testis width, testis volume and testis consistency were, respectively, 0.69, -0.43, -0.31, -0.16, 0.10, 0.87, and between libido and semen volume, sperm motility, vigor, gross motility, major, minor and total defects were, respectively, 0.71, 0.51, 0.12, 0.16, 0.31, 0.26 and 0.43. Results suggested that selection for libido would be effective and that it would lead to desirable correlated response for scrotal circumference, physical and morphological semen traits and undesirable correlated response in body weight.     

Improving Spirulina platensis biomass yield using a fed-batch process

Increasing interest is being shown in the cyanobacterium Spirulina platensis because of its nutritional properties when used as food supplement and possible therapeutic effects. One of the most important areas being studied is the development of alternative nutrient sources which can be used to decrease the production costs of commercially produced S. platensis and obtain high productivity. Water from Mangueira Lagoon (Rio Grande do Sul State, Brazil) has high levels of carbonates and a high pH and has the potential to be used as a culture medium for S. platensis, although some nutrient supplementation may be required. We tested the effect of unsupplemented Mangueira Lagoon water (MLW) or MLW supplemented with 1.125 or 2.250 mg/l of urea and/or 21 or 42 mg/l of sodium bicarbonate on the growth of S. platensis in fed-batch culture using a 3(2) factorial design and found that there the addition of 1.125 mg/l of urea resulted in a 2.67 fold increase times in the final biomass concentration of S. platensis.     

Seed protein variation among pepper (Capsicum sp.) genotypes revealed by MALDI-TOF analysis

A method for seed proteome analysis using MALDI-TOF mass spectrometry is described. The data were used to estimate the genetic diversity degree among twelve genotypes of pepper (Capsicum). The resulting spectra were converted into a binary matrix consisting of 23 protein data sets, and genetic similarity values were calculated with the FreeTree software and Jaccard's coefficient of similarity. We have also been able to identify the presence of certain proteins in the extracts, by checking their masses on on-line databases.     

Cytogenetic studies on Apareiodon affinis (Pisces, Characiformes) from Paraná river basin: sex chromosomes and polymorphism

Comparative cytogenetic studies were carried out on Apareiodon affinis from an important hydrographic system at South America, the Paraná river basin. Two distant regions were chosen, which were separated by Guaíra Falls (formerly Sete Quedas); the region in the upper part of the hydrographic basin is called Upper Paraná (Brazil), whereas and the other in the lower part is called Lower Paraná (Argentina). Individuals from Upper Paraná have diploid numbers of 2n = 54 (NF = 108) for males and 2n = 55 (NF = 110) for females, showing female heterogamety with a ZZ/ZW₁W₂ multiple sex chromosomes system that is endemic for the region. In different localities at Lower Paraná, the specimens presented diploid number of 2n = 54 for both sexes, without any sex chromosomes heteromorphism. However, they have an accentuated polymorphism characterized by variation in number of acrocentric chromosomes, constituting something new for family Parodontidae. The most likely hypothesis to explain the origin of such polymorphism is based on successive pericentric inversions giving rise to acrocentric chromosomes. Thus, it was possible to detect 10 cytotypes along the Lower Paraná basin. Such chromosomal variations possibly are the consequence of an adaptative process. Our data probably indicate the occurrence of distinct species in each region that share the same denomination. This revised version was published online in July 2006 with corrections to the Cover Date.     

Antinociceptive properties of the methanolic extract and two triterpenes isolated from Epidendrum Mosenii stems (Orchidaceae)

The antinociceptive effect of the methanolic extract (ME) and two triterpenes isolated from E. mosenii (Orchidaceae) has been investigated in chemical and thermal models of nociception in mice. The ME of E. mosenii (0.3-30 mg kg(-1), i.p. or 50-400 mg kg(-1), p.o.) produced dose-related, significant and long-lasting (4 to 6 h) inhibition of acetic acid-induced abdominal constriction, with ID50 values of 3.9 and 137.0 mg kg(-1), respectively. Pholidotin and 24-methylenecycloartenol isolated from E. mosenii (0.1-3.0 mg kg(-1), i.p.) also produced marked and dose-related inhibition of acetic acid-induced pain, with ID50 values of 0.9 and 1.1 mg kg(-1). However, these compounds and the ME were about 3- to 13-fold more potent at the level of ID50 than diclofenac when assessed in acetic acid-induced abdominal constriction. The ME of E. mosenii in the same range of doses produced dose-related inhibition of both phases of formalin-induced licking, with mean ID50 values for the first and the second phases of 0.9, 122.0 mg kg(-1) and 0.7, 258.0 mg kg(-1), respectively by i.p. or p.o. routes. In addition, the ME (0.3-30 mg kg(-1), i.p., or 50-400 mg kg(-1), p.o.) also caused dose-related inhibition of capsaicin-induced neurogenic pain with mean ID50 values of 5.2 and 130.0 mg kg(-1), respectively. Treatment of animals with naloxone (5 mg kg(-1), i.p.) completely reversed the antinociceptive effect caused by morphine (5 mg kg(-1), s.c.) and that caused by ME of E. mosenii (1 mg kg(-1), i.p.) when assessed against either phase of the formalin-induced pain. Furthermore, when assessed in the hot-plate test, ME (100 mg kg(-1), i.p.) and morphine (10 mg kg(-1), s.c.) caused significant increase in response latency. However, ME given daily for to 7 consecutive days did not develop tolerance to itself nor did it induce cross-tolerance to morphine. Taken together these data demonstrate that the ME of E. mosenii elicited pronounced antinociception, when assessed by i.p. or p.o. routes, against several models of pain. Its actions involve, at least in part, an interaction with opioid system, seeming no to be related with a non-specific peripheral or central depressant actions. Finally, the active principle(s) responsible for the antinociceptive action of E. mosenii is likely related to the presence of the triterpenes.     

Synthesis and hypolipidemic activity of N-phthalimidomethyl tetra-O-acyl-alpha-D-mannopyranosides

A facile synthesis of anomerically pure phthalimidomethyl 2,3,4,6-tetra-O-acetyl- and phthalimidomethyl 2,3-di-O-acetyl-4,6-di-O-benzoyl-alpha-D-mannopyranosides (6 and 9b) starting from N-hydroxymethylphthalimide and tri-O-acetyl-D-glucal is described. Compounds 3, 6, 8, 9a and 9b have been tested for their hypolipidemic activity in mice. All these compound showed significant reduction of plasma cholesterol and triglyceride levels. Compound 9b has been found to possess the highest activity.