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.     

The digestive tube of Piaractus brachypomus: gross morphology,histology/histochemistry of the mucosal layer and the effects of parasitism by Neoechinorhynchus sp.

The objective of the present study was to describe the histology and histochemistry of the mucosal layer of the digestive tube of Piaractus brachypomus, and the histopathology associated with parasitism by Neoechinorhynchus sp. The digestive tube of P. brachypomus consists of three macroscopically distinct portions: short, rectilinear and elastic-walled ooesophagus, J-shaped siphon stomach and a long intestine with rectilinear and curved portions, defined by patterns of villi as foregut, midgut, and hindgut. Histological and histochemical differences were observed in the mucosal layers of the different digestive tube regions, such as intense production of neutral and acidic mucous substances in the pseudostratified mucosal epithelium of the oesophagus; positive periodic acid Schiff reagent (PAS)reactions at the apex of the columnar epithelial cells of the stomach and increased intensity of histochemical reactions in the hindgut region. Neoechinorhynchus sp. was present in 85.7% of specimens examined, with a mean intensity of 7.4 ± 6.2 (±) and abundance of 6.33. Good health of the fish indicated by high relative condition factor values ( _Kn) and occurrence of only mild to moderate alteration in the mucosal layer indicated that Neoechinorhynchus sp. exhibits low pathogenicity towards P. brachypomus hosts in farming environments, with low levels of infection.     

Sequencing and phylogenetic analyses of talaromyces amestolkiae from amazon: A producer of natural colorants

The population interest in health products is increasing day-by-day. Thus, the demand for natural products to be added in food and pharmaceutical commodity is also rising. Among these additives, colorants, which provides color to products, can be produced by microorganism through bioprocess. Looking for new source of natural colorants, fungi have been employed to this purpose producing novel and safer natural colorants. So, the main goal of this study was to describe a Talaromyces species able to produce natural colorants and investigate nutritional parameters of colorants production using statistical tool. The taxonomy classified the microorganism as Talaromyces amestolkiae. The statistical design evaluated pH and glucose, meat extract and meat peptone concentration as independent variables, and red colorants production as main response. Under the best condition (g/L: glucose 30, meat extract 1, meat peptone 10, and initial pH of 7.0) an increase of 229% in the red colorant production was achieved as compared with the initial media used. The dried fermented broth containing red colorants showed low cytotoxicity against fibroblasts cells (IC₅₀ > 187.5 g/L) and effective antimicrobial activity against S. aureus (MIC of 2.5 g/L). Thus, T. amestolkiae colorants can be attractive to food and pharmaceutical applications as it does not produce toxic compounds and can promote protection against microorganism contaminants. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2684, 2019     

Effects of plyometric jump training on soccer player’s balance: a systematic review and meta-analysis of randomized-controlled trials

Plyometric jump training (PJT) can be used for improving balance through bilateral and unilateral jump-landing drills. Since the increased number of articles testing the effects of PJT on dynamic and static balance, it is relevant to summarize the evidence and determine the effects across different original articles. This systematic review with meta-analysis was conducted to assess the effects of PJT programs on dynamic and static balance in soccer players. The data sources utilized were Cochrane, Medline (PubMed), SPORTDiscus, and Web of Science. (i) Soccer players of any age or sex without injury, illness, or other clinical conditions; (ii) PJT-based programs restricted to a minimum of three weeks (duration); (iii) passive or active control groups; (iv) pre-post interventions values of dynamic and/or static balance; (v) randomized-controlled trials; and (vi) peerreviewed original full-text studies written in English, Portuguese, and/or Spanish. The database search initially identified 803 titles. From those, eight articles were eligible for the systematic review and meta-analysis. The results showed no significant differences between PJT and active controls in dynamic anterior, postero-medial, or postero-lateral balance for both left and right legs (p > 0.05). Additionally, no significant differences were found between PJT and active controls in terms of static balance (p = 0.495). The current evidence suggests that PJT has no significant advantage over active control groups in terms of dynamic or static balance.     

Enhanced heterologous protein production in Pichia pastoris under increased air pressure

Pichia pastoris is a widely used host for the production of heterologous proteins. In this case, high cell densities are needed and oxygen is a major limiting factor. The increased air pressure could be used to improve the oxygen solubility in the medium and to reach the high oxygen demand of methanol metabolism. In this study, two P. pastoris strains producing two different recombinant proteins, one intracellular (β‐galactosidase) and other extracellular (frutalin), were used to investigate the effect of increased air pressure on yeast growth in glycerol and heterologous protein production, using the methanol AOX1‐inducible system. Experiments were carried out in a stainless steel bioreactor under total air pressure of 1 bar and 5 bar. The use of an air pressure raise of up to 5 bar proved to be applicable for P. pastoris cultivation. Moreover, no effects on the kinetic growth parameters and methanol utilization (Mut) phenotype of strains were found, while an increase in recombinant β‐galactosidase‐specific activity (ninefold) and recombinant frutalin production was observed. Furthermore, the air pressure raise led to a reduction in the secreted protease specific activity. This work shows for the first time that the application of an air pressure of 5 bar may be used as a strategy to decrease protease secretion and improve recombinant protein production in P. pastoris. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:1040–1047, 2014     

Morphological and Spatio‐Temporal Mismatches Shape a Neotropical Savanna Plant‐Hummingbird Network

Complex networks of species interactions might be determined by species traits but also by simple chance meetings governed by species abundances. Although the idea that species traits structure mutualistic networks is appealing, most studies have found abundance to be a major structuring mechanism underlying interaction frequencies. With a well‐resolved plant–hummingbird interaction network from the Neotropical savanna in Brazil, we asked whether species morphology, phenology, nectar availability and habitat occupancy and/or abundance best predicted the frequency of interactions. For this, we constructed interaction probability matrices and compared them to the observed plant‐hummingbird matrix through a likelihood approach. Furthermore, a recently proposed modularity algorithm for weighted bipartite networks was employed to evaluate whether these factors also scale‐up to the formation of modules in the network. Interaction frequencies were best predicted by species morphology, phenology and habitat occupancy, while species abundances and nectar availability performed poorly. The plant–hummingbird network was modular, and modules were associated to morphological specialization and habitat occupancy. Our findings highlight the importance of traits as determinants of interaction frequencies and network structure, corroborating the results of a previous study on a plant–hummingbird network from the Brazilian Atlantic Forest. Thus, we propose that traits matter more in tropical plant–hummingbird networks than in less specialized systems. To test the generality of this hypothesis, future research could employ geographic or taxonomic cross‐system comparisons contrasting networks with known differences in level of specialization.     

High-resolution molecular epidemiology and evolutionary history of HIV-1 subtypes in Albania

Background

HIV-1 epidemic in Western Europe is largely due to subtype B. Little is known about the HIV-1 in Eastern Europe, but a few studies have shown that non-B subtypes are quite common. In Albania, where a recent study estimated a ten-fold increase of AIDS incidence during the last six years, subtype A and B account for 90% of the know infections.

Methodology/Principal Findings

We investigated the demographic history of HIV-1 subtype A and B in Albania by using a statistical framework based on coalescent theory and phylogeography. High-resolution phylogenetic and molecular clock analysis showed a limited introduction to the Balkan country of subtype A during the late 1980s followed by an epidemic outburst in the early 1990s. In contrast, subtype B was apparently introduced multiple times between the mid-1970s and mid-1980s. Both subtypes are growing exponentially, although the HIV-1A epidemic displays a faster growth rate, and a significantly higher basic reproductive number R₀. HIV-1A gene flow occurs primarily from the capital Tirane, in the center of the country, to the periphery, while HIV-1B flow is characterized by a balanced exchange between center and periphery. Finally, we calculated that the actual number of infections in Albania is at least two orders of magnitude higher than previously thought.

Conclusions/Significance

Our analysis demonstrates the power of recently developed computational tools to investigate molecular epidemiology of pathogens, and emphasize the complex factors involved in the establishment of HIV-1 epidemics. We suggest that a significant correlation exists between HIV-1 exponential spread and the socio-political changes occurred during the Balkan wars. The fast growth of a relatively new non-B epidemic in the Balkans may have significant consequences for the evolution of HIV-1 epidemiology in neighboring countries in Eastern and Western Europe.     

Quantitative determination of gene strand bias in prokaryotic genomes

Comparative genometrics of microorganisms is a relatively new area, in which genome properties are translated into numerical indexes. Such indexes can be used for a comprehensive and comparative analysis of microbial genomes, contributing to the understanding of their evolution. This work presents a new method for quantitative determination of gene strand bias in prokaryotic chromosomes, in which data transformation of gene position skew leads to a numerical index that can be applied to quantitative comparisons of genome organization. It was applied in the comparative analysis of 49 completely sequenced Firmicutes genomes, allowing the distinction of groups defined according to their patterns of gene strand preference. The resulting groups revealed that, regarding gene strand bias, reduced genomes are, in general, the more disordered among Firmicutes, while genomes of extremophile organisms comprehend those with the highest degree of genome organization in this phylum.