Epstein-Barr virus-positive gastric cancer: a distinct molecular subtype of the disease?

Abstract: Approximately 90% of the world population is infected by Epstein-Barr virus (EBV). Usually, it infects B lymphocytes, predisposing them to malignant transformation. Infection of epithelial cells occurs rarely, and it is estimated that about to 10% of gastric cancer patients harbor EBV in their malignant cells. Given that gastric cancer is the third leading cause of cancer-related mortality worldwide, with a global annual incidence of over 950,000 cases, EBV-positive gastric cancer is the largest group of EBV-associated malignancies. Based on gene expression profile studies, gastric cancer was recently categorized into four subtypes; EBV-positive, microsatellite unstable, genomically stable and chromosomal instability. Together with previous studies, this report provided a more detailed molecular characterization of gastric cancer, demonstrating that EBV-positive gastric cancer is a distinct molecular subtype of the disease, with unique genetic and epigenetic abnormalities, reflected in a specific phenotype. The recognition of characteristic molecular alterations in gastric cancer allows the identification of molecular pathways involved in cell proliferation and survival, with the potential to identify therapeutic targets. These findings highlight the enormous heterogeneity of gastric cancer, and the complex interplay between genetic and epigenetic alterations in the disease, and provide a roadmap to implementation of genome-guided personalized therapy in gastric cancer. The present review discusses the initial studies describing EBV-positive gastric cancer as a distinct clinical entity, presents recently described genetic and epigenetic alterations, and considers potential therapeutic insights derived from the recognition of this new molecular subtype of gastric adenocarcinoma.

Evaluation of human T-lymphotropic virus prevalence/co-infection rates for a four-year period in a non-metropolitan blood center in Southeast Brazil

Abstract: INTRODUCTION: Human T-lymphotropic virus types 1/2 (HTLV-1/2) are distributed worldwide and are endemic in specific regions. METHODS: Serological evaluation of the HTLV-1/2 prevalence and co-infection rate [human immunodeficiency virus (HIV), hepatitis B virus (HBV), hepatitis C virus (HCV), Chagas disease, and syphilis)] for 2011-2014 was performed with volunteer blood donors from the western part of São Paulo State. RESULTS: Serrana and Araçatuba had higher HTLV seroprevalence rates (0.1%); while Franca, Olimpia, and Bebedouro had lower seroprevalences (0.04%). Co-infection (HBV and syphilis) was present in 12.3% of HTLV-infected blood donors. CONCLUSIONS: Our findings provide data for the prevalence of HTLV in Brazil and demonstrate the importance of regional and global hemovigilance.

Prevention of respiratory syncytial virus infections

Respiratory syncytial virus is the most important cause of viral lower respiratory illness in infants and children worldwide. By the age of 2 years, nearly every child has become infected with respiratory syncytial virus and re-infections are common throughout life. Most infections are mild and can be managed at home, but this virus causes serious diseases in preterm children, especially those with bronchopulmonary dysplasia. Respiratory syncytial virus has also been recognized as an important pathogen in people with immunossupressive and other underlying medical problems and institutionalizated elderly, causing thousands of hospitalizations and deaths every year. The burden of these infections makes the development of vaccines for respiratory syncytial virus highly desirable, but the insuccess of a respiratory syncytial virus formalin-inactivated vaccine hampered the progress in this field. To date, there is no vaccine available for preventing respiratory syncytial virus infections, however, in the last years, there has been much progress in the understanding of immunology and immunopathologic mechanisms of respiratory syncytial virus diseases, which has allowed the development of new strategies for passive and active prophylaxis. In this article, the author presents a review about novel approaches to the prevention of respiratory syncytial virus infections, such as: passive immunization with human polyclonal intravenous immune globulin and humanized monoclonal antibodies (both already licensed for use in premature infants and children with bronchopulmonary dysplasia), and many different vaccines that are potential candidates for active immunization against respiratory syncytial virus.

Bronchiolitis, respiratory syncytial virus, and recurrent wheezing: what is the relationship?

Various follow-up studies of children hospitalized with bronchiolitis caused by respiratory syncytial virus have demonstrated that a significant proportion of infants (50%) have recurrent wheezing during childhood. Nevertheless, the relationship between these two entities, if any, has not been established. In order to explain this observation, several hypotheses have been proposed. The first suggests that some children could have an individual predisposition to bronchiolitis caused by respiratory syncytial virus and recurrent wheezing. The virus could be a marker of this condition, and the individual predisposition could in turn be related to an individual hypersensitivity to common allergens (atopy), airway hyperreactivity, or to some disorder related to pulmonary anatomy or physiology that was present before the acute episode of bronchiolitis. Another hypothesis proposes that respiratory syncytial virus could be directly responsible for recurrent wheezing. During an episode of bronchiolitis, the damage in the airway mucosa caused by the vital inflammatory response to infection contributes to sensitivity to other allergens or exposes irritant receptors, resulting in recurrent wheezing. For this review, we analyzed the studies that discuss these hypotheses with the purpose of clarifying the mechanisms for the important issue of recurrent wheezing in childhood.

Hepatitis B: epidemiological, immunological, and serological considerations emphasizing mutation

The global prevalence of hepatitis B virus is estimated to be 350 million chronic carriers, varying widely from low (<2%, as in Western Europe, North America, New Zealand, Australia, and Japan) to high (>8% as in Africa, Southeast Asia, and China). The overall prevalence in Brazil is about 8%. There are currently 7 genotypic variations, from A to G, and also 4 main surface antigen subtypes: adw, ayw, adr, and ayr. There has been great interest in identifying the geographic distribution and prognosis associated with the various genotypes and subtypes. Although the serologic test is highly sensitive and specific, it does not detect cases of mutant hepatitis B, which is increasingly common worldwide due to resistance and vaccine escape, antiviral therapy, and immunosuppression, among other causes. Alterations in surface, polymerase, X region, core, and precore genes have been described. The main mutations occur in surface and in core/precore genes, also known as occult hepatitis, since its serologic markers of active infection (HBsAg) and viral replication (HBeAg) can be negative. Thus, mutation should be suspected when serologic tests to hepatitis B show control of immunity or replication coincident with worsened clinical status and exclusion of other causes of hepatitis.

Forest biomass and wood consumption In the lower course of the Amazon: a case study of rhe Urubueua Island

Várzea and terra-firme forests in the lower course of the Amazon were compared in terms of forest structure, wood volume increments and forest biomass. The wood volume of várzea forests was smaller than that of terra-firme forests, particularly when severe human intervention such as the cultivation of açaí palm occurred. The difference was even greater in the forest weight comparison because of the lower wood density of várzea trees. These trees are not directly influenced by water stress during the dry season, while late wood with a high density is formed in the terra-firme trees. The annual forest disappearance area due to firewood for tile factories was estimated to be about 276 ha on the island investigated, which had an area of 36,200 ha. Assuming that the forests are rotatively cultivated every 25 to 30 years, the total deforestation area is 6,870-6,948 ha in 25 years and 8,244~8,337 ha in 30 years. This result means that the balance between forest biomass and utilization is not in crisis, however, this balance might be lost as long as substitutive energy such as electricity is not supplied.

Leaf herbivory on three tree species in a monodominant and two other Terra firme forests on Maracá Island, Brazil

The aim of this study was to test the hypothesis that the monodominant non-pioneer Peltogyne gracilipes, typically does not suffer density-dependent herbivory (Janzen-Connell model). Two components of intraspecific variation in leaf herbivory were measured: 1) the variation between individuals in the population at the same time and 2) the temporal variation in rates of damage to each individual. The study was carried out on Maracá Island, Roraima, Brazil in three plots (50 m χ 50 m) in each of three forest types: Peltogyne-rich forest (PRF), Peltogyne-poor forest (PPF), and forest without Peltogyne (FWP). Two other non-pioneer species (Ecclinusa guianensis and Pradosia surinamensis) were chosen for comparison because they were fairly abundant and their seedlings could be readily identified. The values of leaf area removed by herbivores of trees and seedlings of the three study species were in the range reported for other tropical tree species (2-16%, standing damage). There were no differences within species between forests. However, there was a significant difference among species but this was not correlated with seedling density. Peltogyne seedlings showed no evidence of density-dependent herbivory as predicted by the Janzen-Connell model despite the fact that adult trees were observed to suffer a mass defoliation in April 1992. This result suggests that Peltogyne may be dominant partly due to escape from herbivory in the early stages of its life although it may suffer occasional mass defoliation as an adult.

Geological control of Podocnemis expansa and Podocnemis unifilis nesting areas in Rio Javaés, Bananal Island, Brazil

The distribution of the nests of Podocnemis expansa (Amazon turtle) and Podocnemis unifilis (yellow-spotted side neck turtle) along the point bars of the Javaés River in Bananal Island, demonstrates a clear preference of these chelonians for differentiated geological environments, in respect to the morphology, grain size or height of the nests in relation to the level of the river. The topographical distribution and the differences in the grain size of the sediments that compose the point bars of the river, originated from the multiple sedimentary processes, and make possible the creation and separation of different nesting environments. Each turtle species takes advantage of the place that presents physiographic characteristics appropriate to the hatching success of their eggs. The superposition of the P. expansa and P. unifilis nest placement areas is rare. The P. expansa nests are concentrated on the central portion of the beaches where successive depositional sedimentary events produced sandy banks more than 3.3 m above the river water level. The P. unifilis nests are distributed preferentially in the upstream and downstream portions along the point bars where the sandy deposits rarely surpass 1.5 m at the moment of laying. P. expansa nests located on the beaches of fine to medium sized sand hatch in a mean of 68 days, while those incubated on beaches of medium to coarse sand size take a mean of 54 days to hatch.

Ethnoveterinary knowledge of the inhabitants of Marajó Island, Eastern Amazonia, Brazil

There have been ethnoveterinary reports from around the world investigating plant usage in therapeutic protocols; however, there is no information regarding the ethnoveterinary practices in Brazilian Amazonia. The objective of this work was to register and document the ethnoveterinary knowledge of the inhabitants of the Island of Marajó, eastern Amazonia, Brazil. In the study, interviews were conducted with 50 individuals, with the application of semi-structured questionnaires that were quantitatively analyzed using descriptive statistic methods of frequency distribution. Use-value was calculated to determine the most important species. Samples of plants that were reported to have medicinal value were collected and identified by botanical classification. Fifty plants, distributed among 48 genera and 34 families, were indicated for 21 different medicinal uses. The family Asteraceae had the largest number of reported species; Carapa guianensis Aubl., Copaifera martii Hayne, Crescentia cujete L., Caesalpinia ferrea Mart., Chenopodium ambrosioides L., Jatropha curcas L. and Momordica charantia L. were species with highest use- value. The plant parts that were more commonly utilized for the preparation of ethnoveterinary medicines were the leaves (56%), bark (18%), roots (14%), seeds (14%) and fruit (8%). With regard to usage, tea was reported as a usage method by 56% of the informants; most preparations (90.9%) utilized only a single plant. In addition to medicinal plants, informants reported using products of animal and mineral origin. The present study contributed to the construction of an inventory of Marajó Island's ethnoveterinary plants, which might be the basis for future scientific validation studies.

Reproductive aspects of Macrobrachium amazonicum (Decapoda: Palaemonidae) in the State of Amapá, Amazon River mouth

Macrobrachium amazonicum is an indigenous prawn vastly distributed in basins of South America, widely exploited by artisanal fisheries in northern and northeastern Brazil and, with great potential for aquaculture. This study aimed to investigate general aspects of population structure and reproductive characteristics (size at first maturity, fecundity and reproductive output) of M. amazonicum from two important areas to artisanal prawn fishing located at the mouth of the Amazon River, State of Amapá. The specimens were captured using 20 handcrafted traps called "matapi". A number of 5,179 prawns were captured, 2,975 females and 2,195 males resulting in 1.35:1 female to male ratio. Santana Island and Mazagão Velho showed females predominated in the population. A reproductive peak period was observed from January to April/2009 and in December/2010, coinciding with the period of higher rainfall. The recruitment peak occurred in June and July/2009. Egg-bearing females ranged in size (carapace length) from 11.10 to 29.6 mm. Fecundity increased with female size and reached up to 7,417 eggs. This amount of eggs is considered low if compared with other Macrobrachium estuarine species. Mean egg volume increased gradually from 0.121 to 0.24 mm³ during embryogenesis, representing 68.5% of overall increase from Stage I to Stage III. Eggs of M. amazonicum are small; this is typical for Macrobrachium species, which depends on brackish water to complete the larval development. Irrespective of female size, reproductive output of M. amazonicum varied between 4.8 and 21.85% of their body weight into eggs production.

Vegetational changes during the last millennium inferred from a palynological record from the Bananal Island, Tocantins, Brazil

The Bananal Island is regarded the largest fluvial island in the world, bounded by Araguaia and Javaés rivers, being located in southwest of Tocantins. The objectives of this work were to provide information about the vegetational changes that occurred at the Bananal Island, in order to contribute to the understanding the dynamics of past and current savanna and areas of ecotones with forests. Thus, a sedimentary core collected from a small lake at the Bananal Island plain was submitted to pollen and radiocarbon dating analyses. The results showed that the last millennium was dominated by forest reflecting a wet climate. At the beginning of the record (920-770 yr cal BP) the wet climate and high rainfall produced flooding during long rainy seasons that maintained the Javaés River connected to the studied lake, and hence, this environment was marked by the presence of a homogenous forest rich in Moraceae/Urticaceae, due to flooded soils occurrence. During the following period (770-304 yr cal BP) the reduced rainfall and shortening of the rainy seasons isolated the lake from the Javaés River for long periods, which caused a diversification of the forest and gave rise to the appearance of the components of floodplain forest and marsh vegetation adapted to waterlogged soils. Since 304 years cal BP to the present day this environment remained dominated by this diverse forest and the lacustrine conditions were also similar to previous phase, with a slight increase of moisture in the last 84 years that caused the increase of Piranhea.

Great amount of C.pneumoniae in ruptured plaque vessel segments at autopsy. A comparative study with stable plaques

A possible relationship between C.pneumoniae (CP) infection, atherosclerosis and acute myocardial infarction is a debated matter. Now we performed the search of CP in histological segments of fatal ruptured plaques and of stable plaques by histochemistry (Macchiavello stain), immunohistochemistry and in situ hybridization techniques. Electron microscopy and confocal laser microscopy techniques were used in two additional cases. The semi-quantitification of CP + cells (0-4+) and quantification of lymphocytes demonstrated greater amount of CP + cells and more inflammation in the adventitia of vulnerable plaque vessel segments than of stable ones, larger amount of CP + cells in adventitia than in the plaque and high frequency of CP + cells in all groups studied. This preliminary study strongly suggests a direct pathogenetic involvement of adventitial CP in the rupture of the atheromatous plaque, development of acute myocardial infarction and also in the development of atherosclerosis.

Echocardiographic diagnosis of transposition of the great arteries associated with anomalous pulmonary venous connection

We report 2 cases of transposition of the great arteries associated with anomalous pulmonary venous connection emphasizing the clinical findings, the diagnosis, and the evolution of the association. One of the patients had the anomalous pulmonary venous connection in its total infradiaphragmatic form, in the portal system, and the other patient had a partial form, in which an anomalous connection of the left superior lobar vein with the innominate vein existed. At the time of hospital admission, the patients had cyanosis and respiratory distress with clinical findings suggesting transposition of the great arteries. The diagnosis in 1 of the cases, in which the anomalous connection was partial, was established only with echocardiography, without invasive procedures that would represent risk for the patient; in the other case, in which the anomalous connection was total, the malformation was only evidenced with catheterization. The patients underwent surgery for anatomical correction of the heart disease. Only 1 patient had a good outcome.