Protective and risk factors for toxocariasis in children from two different social classes of Brazil

The aim of this study was to analyze the prevalence of Toxocara spp. antibodies in children from two different socioeconomic classes in the Presidente Prudente municipality, São Paulo State, Brazil, and the protective and risk factors associated with toxocariasis. One hundred and twenty-six middle-class (MC) and 126 disadvantaged children (DC) were included in this study. Anti-Toxocara ELISA test was performed in order to evaluate seroprevalence. A survey was applied to the children's guardians/parents in order to analyze the protective and risk factors. The overall prevalence was 11.1%, and of 9.5% (12/126) and 12.7% (16/126) for MC and DC subgroups, respectively. Toxocara seropositivity was inversely proportional to the family income. A high household income was considered a protective factor for toxocariasis in the total population and in both MC and DC subgroups. Being a girl was considered a protective factor for the total population and for both subgroups. Whilst being an owner of cat was a risk factor for children belonging to the total and for both MC and DC subgroups, having dog was considered as a risk factor for only the MC. Epidemiologic protective/factor risks can be distinct depending on the strata of the same population. Thus, it is relevant to evaluate these factors independently for different socioeconomic classes in order to design future investigations and programs for preventing the infection of human beings by Toxocara spp. and other geohelminths.

Assessment of pedotransfer functions for estimating soil water retention curves for the amazon region

Knowledge of the soil water retention curve (SWRC) is essential for understanding and modeling hydraulic processes in the soil. However, direct determination of the SWRC is time consuming and costly. In addition, it requires a large number of samples, due to the high spatial and temporal variability of soil hydraulic properties. An alternative is the use of models, called pedotransfer functions (PTFs), which estimate the SWRC from easy-to-measure properties. The aim of this paper was to test the accuracy of 16 point or parametric PTFs reported in the literature on different soils from the south and southeast of the State of Pará, Brazil. The PTFs tested were proposed by Pidgeon (1972), Lal (1979), Aina & Periaswamy (1985), Arruda et al. (1987), Dijkerman (1988), Vereecken et al. (1989), Batjes (1996), van den Berg et al. (1997), Tomasella et al. (2000), Hodnett & Tomasella (2002), Oliveira et al. (2002), and Barros (2010). We used a database that includes soil texture (sand, silt, and clay), bulk density, soil organic carbon, soil pH, cation exchange capacity, and the SWRC. Most of the PTFs tested did not show good performance in estimating the SWRC. The parametric PTFs, however, performed better than the point PTFs in assessing the SWRC in the tested region. Among the parametric PTFs, those proposed by Tomasella et al. (2000) achieved the best accuracy in estimating the empirical parameters of the van Genuchten (1980) model, especially when tested in the top soil layer.

Carbon monoxide: from toxin to endogenous modulator of cardiovascular functions

Carbon monoxide (CO) is a pollutant commonly recognized for its toxicological attributes, including CNS and cardiovascular effects. But CO is also formed endogenously in mammalian tissues. Endogenously formed CO normally arises from heme degradation in a reaction catalyzed by heme oxygenase. While inhibitors of endogenous CO production can raise arterial pressure, heme loading can enhance CO production and lead to vasodepression. Both central and peripheral tissues possess heme oxygenases and generate CO from heme, but the inability of heme substrate to cross the blood brain barrier suggests the CNS heme-heme oxygenase-CO system may be independent of the periphery. In the CNS, CO apparently acts in the nucleus tractus solitarii (NTS) promoting changes in glutamatergic neurotransmission and lowering blood pressure. At the periphery, the heme-heme oxygenase-CO system can affect cardiovascular functions in a two-fold manner; specifically: 1) heme-derived CO generated within vascular smooth muscle (VSM) can promote vasodilation, but 2) its actions on the endothelium apparently can promote vasoconstriction. Thus, it seems reasonable that the CNS-, VSM- and endothelial-dependent actions of the heme-heme oxygenase-CO system may all affect cardiac output and vascular resistance, and subsequently blood pressure.

A method for multiple sequential analyses of macrophage functions using a small single cell sample

Microbial pathogens such as bacillus Calmette-Guérin (BCG) induce the activation of macrophages. Activated macrophages can be characterized by the increased production of reactive oxygen and nitrogen metabolites, generated via NADPH oxidase and inducible nitric oxide synthase, respectively, and by the increased expression of major histocompatibility complex class II molecules (MHC II). Multiple microassays have been developed to measure these parameters. Usually each assay requires 2-5 x 10(5) cells per well. In some experimental conditions the number of cells is the limiting factor for the phenotypic characterization of macrophages. Here we describe a method whereby this limitation can be circumvented. Using a single 96-well microassay and a very small number of peritoneal cells obtained from C3H/HePas mice, containing as little as <=2 x 10(5) macrophages per well, we determined sequentially the oxidative burst (H2O2), nitric oxide production and MHC II (IAk) expression of BCG-activated macrophages. More specifically, with 100 µl of cell suspension it was possible to quantify H2O2 release and nitric oxide production after 1 and 48 h, respectively, and IAk expression after 48 h of cell culture. In addition, this microassay is easy to perform, highly reproducible and more economical.

Oxidative stress: molecular perception and transduction of signals triggering antioxidant gene defenses

Molecular oxygen (O2) is the premier biological electron acceptor that serves vital roles in fundamental cellular functions. However, with the beneficial properties of O2 comes the inadvertent formation of reactive oxygen species (ROS) such as superoxide (O2·-), hydrogen peroxide, and hydroxyl radical (OH·). If unabated, ROS pose a serious threat to or cause the death of aerobic cells. To minimize the damaging effects of ROS, aerobic organisms evolved non-enzymatic and enzymatic antioxidant defenses. The latter include catalases, peroxidases, superoxide dismutases, and glutathione S-transferases (GST). Cellular ROS-sensing mechanisms are not well understood, but a number of transcription factors that regulate the expression of antioxidant genes are well characterized in prokaryotes and in yeast. In higher eukaryotes, oxidative stress responses are more complex and modulated by several regulators. In mammalian systems, two classes of transcription factors, nuclear factor kB and activator protein-1, are involved in the oxidative stress response. Antioxidant-specific gene induction, involved in xenobiotic metabolism, is mediated by the "antioxidant responsive element" (ARE) commonly found in the promoter region of such genes. ARE is present in mammalian GST, metallothioneine-I and MnSod genes, but has not been found in plant Gst genes. However, ARE is present in the promoter region of the three maize catalase (Cat) genes. In plants, ROS have been implicated in the damaging effects of various environmental stress conditions. Many plant defense genes are activated in response to these conditions, including the three maize Cat and some of the superoxide dismutase (Sod) genes.

Health promoting and sensory properties of phenolic compounds in food

Phenolic compounds have been extensively studied in recent years. The presence of these compounds in various foods has been associated with sensory and health promoting properties. These products from the secondary metabolism of plants act as defense mechanisms against environmental stress and attack by other organisms. They are divided into different classes according to their chemical structures. The objective of this study was to describe the different classes of phenolic compounds, the main food sources and factors of variation, besides methods for the identification and quantification commonly used to analyze these compounds. Moreover, the role of phenolic compounds in scavenging oxidative stress and the techniques of in vitro antioxidant evaluation are discussed. In vivo studies to evaluate the biological effects of these compounds and their impact on chronic disease prevention are presented as well. Finally, it was discussed the role of these compounds on the sensory quality of foods.

Towards a unified theory of health-disease: II. Holopathogenesis

This article presents a systematic framework for modeling several classes of illness-sickness-disease named as Holopathogenesis. Holopathogenesis is defined as processes of over-determination of diseases and related conditions taken as a whole, comprising selected facets of the complex object Health. First, a conceptual background of Holopathogenesis is presented as a series of significant interfaces (biomolecular-immunological, physiopathological-clinical, epidemiological-ecosocial). Second, propositions derived from Holopathogenesis are introduced in order to allow drawing the disease-illness-sickness complex as a hierarchical network of networks. Third, a formalization of intra- and inter-level correspondences, over-determination processes, effects and links of Holopathogenesis models is proposed. Finally, the Holopathogenesis frame is evaluated as a comprehensive theoretical pathology taken as a preliminary step towards a unified theory of health-disease.

Evaluation of different methods for Plasmodia detection, in well defined population groups in an endemic area of Brazil

In Brazil, more than 500,000 new cases of malaria were notified in 1992. Plasmodium falciparum and P.vivax are the responsible species for 99.3% of the cases. For adequate treatment, precoce diagnosis is necessary. In this work, we present the results of the traditional Plasmodia detection method, thick blood film (TBF), and the results of alternative methods: Immunofluorescence assay (IFA) with polyclonal antibody and Quantitative Buffy Coat method (QBC)® in a well defined population groups. The analysis were done in relation to the presence or absence of malaria clinical symptoms. Also different classes of immunoglobulins anti-P.falciparum were quantified for the global analysis of the results, mainly in the discrepant results. We concluded that alternative methods are more sensitive than TBF and that the association of epidemiological, clinical and laboratory findings is necessary to define the presence of malaria.

Characterization of Vibrio Parahaemolyticus isolated from oysters and mussels in São Paulo, Brazil

Vibrio parahaemolyticus is a marine bacterium, responsible for gastroenteritis in humans. Most of the clinical isolates produce thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) encoded by tdh and trh genes respectively. In this study, twenty-three V. parahaemolyticus, previously isolated from oysters and mussels were analyzed by PCR using specific primers for the 16S rRNA and virulence genes (tdh, trh and tlh) and for resistance to different classes of antibiotics and PFGE. Nineteen isolates were confirmed by PCR as V. parahaemolyticus. The tlh gene was present in 100% of isolates, the tdh gene was identified in two (10.5%) isolates, whereas the gene trh was not detected. Each isolate was resistant to at least one of the nine antimicrobials tested. Additionally, all isolates possessed the blaTEM-116 gene. The presence of this gene in V. parahaemolyticus indicates the possibility of spreading this gene in the environment. Atypical strains of V. parahaemolyticus were also detected in this study.

Relationship between antibiotic consumption, oropharyngeal colonization, and ventilator-associated pneumonia by Staphylococcus aureus in an intensive care unit of a Brazilian teaching hospital

INTRODUCTION: his study evaluated the consumption of major classes of antibiotics, the colonization of the oropharynx of patients on mechanical ventilation, and the risk of ventilator-associated pneumonia (VAP) caused by Staphylococcus aureus in an intensive care unit for adults. METHODS: A case-control study was carried out using colonized patients (cases) by oxacillin-resistant S. aureus (ORSA) and (controls) oxacillin-sensitive S. aureus (OSSA) from May 2009 to August 2010. The occurrence of VAP by S. aureus was also evaluated in the same period. Antibiotic consumption was expressed as the number of defined daily doses (DDD)/1,000 patient-days for glycopeptides, carbapenems, and extended-spectrum cephalosporins. RESULTS: Three hundred forty-six (56.1%) patients underwent mechanical ventilation with a frequency of oropharyngeal colonization of 36.4%, corresponding to 63.5% for ORSA and 36.5% for OSSA. The risk of illness for this organism was significant (p<0.05), regardless of whether colonization/infection was by ORSA or OSSA. The consumption of antibiotics was high, mainly for broad-spectrum cephalosporins (551.26 DDDs/1,000 patient-days). The high density of use of glycopeptides (269.56 DDDs/1,000 patient-days) was related to colonization by ORSA (Pearson r=0.57/p=0.02). Additionally, age >60 years, previous antibiotic therapy, and previous use of carbapenems were statistically significant by multivariate analysis. CONCLUSIONS: There was a significant relationship between the colonization of the oropharyngeal mucosa and the risk of VAP by both phenotypes. The use of glycopeptides was related to colonization by ORSA.

Nurses' training on dealing with alcohol and drug abuse: a question of necessity

The purpose of this article is to present a brief review on the need for changes in nurses' undergraduate education concerning alcohol and drugs. Specialized literature makes it clear that nurses have difficulties giving care to psychoactive substance users as part of their functions in the various health care sites. This may be associated with a deficiency in formal education. In the face of the social importance concerning these related questions in the scope of research, care, and education, we made an attempt at deepening the study on this theme, which could contribute to changes in practice, care, and undergraduate nursing education.

Cognitive processes affect the gait of subjects with Parkinson’s and Alzheimer’s disease in dual tasks

Objective To investigate the relation between gait parameters and cognitive impairments in subjects with Parkinson’s disease (PD) and Alzheimer’s disease (AD) during the performance of dual tasks. Methods This was a cross-sectional study involving 126 subjects divided into three groups: Parkinson group (n = 43), Alzheimer group (n = 38), and control group (n = 45). The subjects were evaluated using the Timed Up and Go test administered with motor and cognitive distracters. Gait analyses consisted of cadence and speed measurements, with cognitive functions being assessed by the Brief Cognitive Screening Battery and the Clock Drawing Test. Statistical procedures included mixed-design analyses of variance to observe the gait patterns between groups and tasks and the linear regression model to investigate the influence of cognitive functions in this process. A 5% significant level was adopted. Results Regarding the subjects’ speed, the data show a significant difference between group vs task interaction (p = 0.009), with worse performance of subjects with PD in motor dual task and of subjects with AD in cognitive dual task. With respect to cadence, no statistical differences was seen between group vs task interaction (p = 0.105), showing low interference of the clinical conditions on such parameter. The linear regression model showed that up to 45.79%, of the variance in gait can be explained by the interference of cognitive processes. Conclusion Dual task activities affect gait pattern in subjects with PD and AD. Differences between groups reflect peculiarities of each disease and show a direct interference of cognitive processes on complex tasks.

Population biology of the crab Armases angustipes (Crustacea, Decapoda, Sesarmidae) at Brazilian tropical coast

The semi terrestrial crabs are important elements of the fauna of coastal regions. The aim of this study was to analyze the population structure of Armases angustipes (Dana, 1852) at estuaries of the Ariquindá River, considered a non impacted area, and Mamucabas River, considered a few impacted area, on the south coast of state of Pernambuco, Brazil. The species occurred in all months of the year. The number of individuals per month varied, being higher in the months of transition between the seasons. This is probably due to significant seasonal variations of air and burrow temperature and burrow salinity. There was no sexual dimorphism in size of A. angustipes in the mangrove of Ariquindá River, but males were larger than females in the mangrove of Mamucabas River. In both estuaries, the sex ratio did not differ from Mendelian proportion, but showed a deviation for females. The analysis of temporal variation in sex ratio showed significant differences in some months of the year. These variations are due to cyclical events that act distinctly on each sex. In both estuaries, size classes of carapace width were equally represented by both sexes. The ovigerous females of A. angustipes occurred only in some months of the year, especially in summer, in both estuaries. Probably the high phytoplankton productivity observed in summer favors the reproductive activity, since these algae serve as food for the larvae. Specimens of the population of Rio Ariquindá are largest and wider than those of Mamucabas River. This fact, associated with the low abundance of crabs and the lower frequency of ovigerous females observed in Mamucabas River, is an indication that this population may be influenced by the environmental impacts that this estuary has received.

Differentation of the fat body cells in the precocius adults of Schistocerca gregaria: regulation of polyploidy by juvenile hormone

Precocious adults from 2nd and 3rd instar larvae of the desert locust Schistocerca gregaria were used to assess the competence of their fat body to synthesize DNA in response to a juvenile hormone analog (JHA), hydoprene. Autoradiographic studies show that JHA stimulates DNA synthesis since a significant proportion of the fat body nuclei are labelled after treatment with 100 or 200 µg of JHA. Maximum DNA synthesis occurs 24 h after treatment with 100 µg of JHA. The nuclear ploidy classes of the precocious adults from 3rd larvae are similar to those of 1-d-old normal adults, but treatemnt of these precociuos adults with µg of JHA doubles the DNA content resulting in enhanced ploidy classes which resemble those of 10-d-old normal females. In the precocious adults that emerged from 2nd instar larvae the ploidy classes are higher than those of 1-d-old normal adults, and treatment of these precocious adults with JHA results in a further increase in the DNA content of the fat body nuclei leading to the formation of high percentages of 16C and 32C nuclei. The results of these studies suggest that any model on the mode of action of JH should recognize this phenomenon of JH-induced polyploidization in the fat body nuclei.