Trypanosoma Cruzi: Pattern of Rna Synthesis Following Infection of Vertebrate Cells

SYNOPSIS. the pattern of RNA synthesis of intracellular Trypanosoma cruzi amastigotes, immediately following infection of Lesch-Nyhan human fibroblasts, was studied by autoradiography. Amastigote RNA synthesis, determined by [₃H]guanine incorporation, was not detected until 2 h after infection. At 8 h postinfection more than 90% of intracellular amastigotes were labeled. It was verified that extracellular trypomastigotes also synthesized RNA. Therefore it was concluded that, if RNA is required for trypomastigote-to-amastigote transformation, this nucleic acid is already present in the trypomastigotes before infection of the vertebrate cell. It is probable that the RNA synthesized by amastigotes during the prereplicative lag period (the period between initial infection and the onset of DNA synthesis) is required for intracellular growth and reproduction.     

What is “functional impairment”? Disentangling disability from clinical significance

The formulation of disability (or “functional impairment”) is currently not operationalized in either the ICD or the DSM. In the DSM system, making a diagnosis depends on a conjoint assessment of symptoms and functioning, whereas the ICD keeps the disability construct separate from the diagnosis of mental disorders. We need an internationally agreed conceptualization between ICD and DSM in terms of better operationalization of disease and disability components. No functioning or disability should appear as part of the threshold of the diagnosis in either system.     

Down‐regulation of catalase activity allows transient accumulation of a hydrogen peroxide signal in Chlamydomonas reinhardtii

In photosynthetic organisms, excess light is a stress that induces production of reactive oxygen species inside the chloroplasts. As a response, the capacity of antioxidative defence mechanisms increases. However, when cells of Chlamydomonas reinhardtii were shifted from dark to high light, a reversible partial inactivation of catalase activity was observed, which correlated with a transient increase in the level of H₂O₂ in the 10 μm range. This concentration range seems to be necessary to activate H₂O₂‐dependent signalling pathways stimulating the expression of H₂O₂ responsive genes, such as the heat shock protein HSP22C. Catalase knock‐down mutants had lost the transient accumulation of H₂O₂, suggesting that a decrease in catalase activity was the key element for establishing a transient H₂O₂ burst. Catalase was inactivated by a one‐electron event consistent with the reduction of a single cysteine. We propose that under high light intensity, the redox state of the photosynthetic electron transport chain is sensed and transmitted to the cytosol to regulate the catalase activity. This allows a transient accumulation of H₂O₂, inducing a signalling event that is transmitted to the nucleus to modulate the expression of chloroplast‐directed protection enzymes.     

Developmental expression of DAX1 in the European sea bass, Dicentrarchus labrax: lack of evidence for sexual dimorphism during sex differentiation

Background  

DAX1 (NR0B1), a member of the nuclear receptors super family, has been shown to be involved in the genetic sex determination and in gonadal differentiation in several vertebrate species. In the aquaculture fish European sea bass, Dicentrarchus labrax, and in the generality of fish species, the mechanisms of sex determination and differentiation have not been elucidated. The present study aimed at characterizing the European DAX1 gene and its developmental expression at the mRNA level.     

Lifetime prevalence and age-of-onset distributions of mental disorders in the World Health Organization's World Mental Health Survey Initiative

Data are presented on the lifetime prevalence, projected lifetime risk, and age-of-onset distributions of mental disorders in the World Health Organization (WHO)''s World Mental Health (WMH) Surveys. Face-to-face community surveys were conducted in seventeen countries in Africa, Asia, the Americas, Europe, and the Middle East. The combined numbers of respondents were 85,052. Lifetime prevalence, projected lifetime risk, and age of onset of DSM-IV disorders were assessed with the WHO Composite International Diagnostic Interview (CIDI), a fully-structured lay administered diagnostic interview. Survival analysis was used to estimate lifetime risk. Median and inter-quartile range (IQR) of age of onset is very early for some anxiety disorders (7-14, IQR: 8-11) and impulse control disorders (7-15, IQR: 11-12). The age-of-onset distribution is later for mood disorders (29-43, IQR: 35-40), other anxiety disorders (24-50, IQR: 31-41), and substance use disorders (18-29, IQR: 21-26). Median and IQR lifetime prevalence estimates are: anxiety disorders 4.8-31.0% (IQR: 9.9-16.7%), mood disorders 3.3-21.4% (IQR: 9.8-15.8%), impulse control disorders 0.3-25.0% (IQR: 3.1-5.7%), substance use disorders 1.3-15.0% (IQR: 4.8-9.6%), and any disorder 12.0-47.4% (IQR: 18.1-36.1%). Projected lifetime risk is proportionally between 17% and 69% higher than estimated lifetime prevalence (IQR: 28-44%), with the highest ratios in countries exposed to sectarian violence (Israel, Nigeria, and South Africa), and a general tendency for projected risk to be highest in recent cohorts in all countries. These results document clearly that mental disorders are commonly occurring. As many mental disorders begin in childhood or adolescents, interventions aimed at early detection and treatment might help reduce the persistence or severity of primary disorders and prevent the subsequent onset of secondary disorders.     

Characterization of microsatellite loci isolated in Mountain Plover (Charadrius montanus)

Primers for 15 microsatellite loci were developed for Mountain Plover, a species whose distribution and abundance have been reduced drastically in the past 30 years. In a screen of 126 individuals collected from four breeding locales across the species’ range, levels of polymorphism ranged from two to 13 alleles per locus. No two loci were found to be linked, although one locus revealed significant departures from Hardy–Weinberg equilibrium. These microsatellite loci can be used in population genetic studies, ultimately aiding in management efforts for Mountain Plover. Additionally, these markers can potentially be used in studies investigating the mating system of Mountain Plover.     

Weight loss is not mandatory for exercise-induced effects on health indices in females with metabolic syndrome

The aim of this study was to investigate the impact of moderate aerobic training on functional, anthropometric, biochemical, and health-related quality of life (HRQOL) parameters on women with metabolic syndrome (MS). Fifteen untrained women with MS performed moderate aerobic training for 15 weeks, without modifications of dietary behaviours. Functional, anthropometric, biochemical, control diet record and HRQOL parameters were assessed before and after the training. Despite body weight maintenance, the patients presented decreases in waist circumference (P = 0.001), number of MS components (P = 0.014), total cholesterol (P = 0.049), HDL cholesterol (P = 0.004), LDL cholesterol (P = 0.027), myeloperoxidase activity (P = 0.002) and thiobarbituric acid-reactive substances levels (P = 0.006). There were no differences in total energy, carbohydrate, protein and lipid intake pre- and post-training. Furthermore, improvements in the HRQOL subscales of physical functioning (P = 0.03), role-physical (P = 0.039), bodily pain (P = 0.048), general health (P = 0.046) and social functioning scoring (P = 0.011) were reported. Despite the absence of weight loss, aerobic training induced beneficial effects on functional, anthropometric, biochemical and HRQOL parameters in women with MS.     

Purification of Eimeria Sporozoites by DE-52 Anion Exchange Chromatography

An anion exchange column of DE-52 has been used to purify Eimeria sporozoites from a post-excystation mixture of oocysts, oocyst shells, sporocysts, sporocyst shells, and sporozoites. The mean recovery from several experiments was 94% and virtually all non-sporozoite material was removed. Infectivity studies in vitro with sporozoites showed that they were viable after purification and were at least as infectious as the unpurified sporozoites; furthermore, oocysts in the crude preparation could be recovered from the DE-52 cellulose by resuspending them in a 20% (w/v) sodium chloride solution.