56 resultados para Helen Kelsh
Resumo:
The superior cervical ganglion (SCG) in mammals varies in structure according to developmental age, body size, gender, lateral asymmetry, the size and nuclear content of neurons and the complexity and synaptic coverage of their dendritic trees. In small and medium-sized mammals, neuron number and size increase from birth to adulthood and, in phylogenetic studies, vary with body size. However, recent studies on larger animals suggest that body weight does not, in general, accurately predict neuron number. We have applied design-based stereological tools at the light-microscopic level to assess the volumetric composition of ganglia and to estimate the numbers and sizes of neurons in SCGs from rats, capybaras and horses. Using transmission electron microscopy, we have obtained design-based estimates of the surface coverage of dendrites by postsynaptic apposition zones and model-based estimates of the numbers and sizes of synaptophysin-labelled axo-dendritic synaptic disks. Linear regression analysis of log-transformed data has been undertaken in order to establish the nature of the relationships between numbers and SCG volume (V(scg)). For SCGs (five per species), the allometric relationship for neuron number (N) is N=35,067xV (scg) (0.781) and that for synapses is N=20,095,000xV (scg) (1.328) , the former being a good predictor and the latter a poor predictor of synapse number. Our findings thus reveal the nature of SCG growth in terms of its main ingredients (neurons, neuropil, blood vessels) and show that larger mammals have SCG neurons exhibiting more complex arborizations and greater numbers of axo-dendritic synapses.
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Stellate ganglion (SG) represents the main sympathetic input to the heart. This study aimed at investigating physical exercise-related changes in the quantitative aspects of SG neurons in treadmill-exercised Wistar rats. By applying state-of-the-art design-based stereology, the SG volume, total number of SG neurons, mean perikaryal volume of SG neurons, and the total volume of neurons in the whole SG have been examined. Arterial pressure and heart rate were also measured at the end of the exercise period. The present study showed that a low-intensity exercise training program caused a 12% decrease in the heart rate of trained rats. In contrast, there were no effects on systolic pressure, diastolic pressure, or mean arterial pressure. As to quantitative changes related to physical exercise, the main findings were a 21% increase in the fractional volume occupied by neurons in the SG, and an 83% increase in the mean perikaryal volume of SG neurons in treadmill-trained rats, which shows a remarkable neuron hypertrophy. It seems reasonable to infer that neuron hypertrophy may have been the result of a functional overload imposed on the SG neurons by initial posttraining sympathetic activation. From the novel stereological data we provide, further investigations are needed to shed light on the mechanistic aspect of neuron hypertrophy: what role does neuron hypertrophy play? Could neuron hypertrophy be assigned to the functional overload induced by physical exercise? (C) 2008 Wiley-Liss, Inc.
Resumo:
Sodium hypochlorite solution is toxic to vital tissues, causing severe effects if extruded during endodontic treatment. This paper presents a report on the tissue damage related to inadvertent extrusion of concentrated sodium hypochlorite solution during root canal treatment. A 65-year-old woman was referred with moderate pain, ecchymosis, and severe swelling of the right side of the face. These symptoms appeared immediately after a root canal treatment of the maxillary right canine, which had been started 21 hours earlier. It was diagnosed as air emphysema related to sodium hypochlorite solution extravasation during the endodontic treatment. To avoid this, an initial radiograph should be taken to determine the correct canal working length and confirm root canal integrity. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 108: e46-e49)
Resumo:
Objective. Estimate cataract surgical rates (CSR) for Brazil and each federal unit in 2006 and 2007 based on the number of surgeries performed by the Unified Health System to help plan a comprehensive ophthalmology network in order to eliminate cataract blindness in compliance with the target set by the World Health Organization (WHO) of 3 000 cataract surgeries per million inhabitants per year. Methods. This descriptive study calculates CSR by using the number of cataract surgeries carried out by the Brazilian Unified Health System for each federal unit and estimates the need for cataract surgery in Brazil for 2006-2007, with official population data provided by the Brazilian Institute of Geography and Statistics. The number of cataract surgeries was compared with the WHO target. Results. To reach the WHO goal for eliminating age-related cataract blindness in Brazil, 560 312 cataract surgeries in 2006 and 568 006 surgeries in 2007 needed to be done. In 2006, 179 121 cataract surgeries were done by the Unified Health System, corresponding to a CSR of 959 per million population; in 2007, 223 317 were performed, with a CSR of 1 179. With the Brazilian Council of Ophthalmology estimation of 165 000 surgeries each year by the non-public services, the CSR for Brazil would be 1 842 for 2006 and 2 051 for 2007. The proportions needed to achieve the proposed target were 38.6% in 2006 and 31.6% in 2007. Conclusions. Human resources, technical expertise, and equipment are crucial to reach the WHO goal. Brazil has enough ophthalmologists but needs improved planning and infrastructure in order to eliminate the problem, aspects that require greater financial investment and stronger political commitment.
Resumo:
Antioxidants probably play an important role in the etiology of type 2 diabetes (DM2). This study evaluated the effects of supplementation with lipoic acid (LA) and alpha-tocopherol on the lipid profile and insulin sensitivity of DM2 patients. A randomized, double-blind, placebo-controlled trial involving 102 DM2 patients divided into four groups to receive daily supplementation for 4 months with: 600 mg LA (n = 26); 800 mg alpha-tocopherol (n = 25); 800 mg alpha-tocopherol + 600 mg LA (n = 25); placebo (n = 26). Plasma alpha-tocopherol, lipid profile, glucose, insulin, and the HOMA index were determined before and after supplementation. Differences within and between groups were compared by ANOVA using Bonferroni correction. Student`s t-test was used to compare means of two independent variables. The vitamin E/total cholesterol ratio improved significantly in patients supplemented with vitamin E + LA and vitamin E alone (p <= 0.001). There were improvements of the lipid fractions in the groups receiving LA and vitamin E alone or in combination, and on the HOMA index in the LA group, but not significant. The results suggest that LA and vitamin E supplementation alone or in combination did not affect the lipid profile or insulin sensitivity of DM2 patients. (C) 2011 Elsevier Ireland Ltd. All rights reserved.
Resumo:
This cross-sectional study determined the influence of antiretroviral therapy (ART) on the lipid profile and insulin sensitivity of 119 perinatally HIV-infected Brazilian patients aged 6-19 years. Inadequate high-density lipoprotein cholesterol (HDL-c) concentrations were observed in 81.4% of patients. High concentrations of total cholesterol (TC), low-density lipoprotein cholesterol (LDI.-c) and triglycerides (TG) were found in 33.9%, 9.7% and 35.6% of patients, respectively. There were statistically significant differences in mean concentrations of TC (P=0.004), HDL-c (P=0.015) and LDL-c (P=0.028) among children (< 10 years), early adolescents (10-14 years) and late adolescents (15-19 years). Children presented the highest mean concentrations of TC and LDL-c, and patients in late adolescence presented the lowest concentrations of HDL-c. Insulin sensitivity, assessed by the Homeostasis Model Assessment (HOMA) index, was diagnosed in 16.7% of patients, with a statistically higher proportion (P=0.034) of insulin-resistant children (33.3%) compared with adolescents (12.5%). There was a statistically significant association between TG concentrations and use of ART regimens containing protease inhibitors (PI) (P=0.0003). Children presented a higher prevalence of insulin resistance and dyslipidaemia compared with adolescents, suggesting that ART, especially Pls, may lead to metabolic complications. (C) 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.
Resumo:
The objective of this cross-sectional study was to assess the nutritional status of children and adolescents with human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) receiving highly active antiretroviral therapy (HAART). One hundred and eighteen subjects aged 6-19 years attending an outpatient clinic in Sao Paulo city were involved in the study. The following anthropometric measurements were assessed: weight, height, waist circumference and triceps and subscapular skinfold thickness. One (0.9%) adolescent was diagnosed with abdominal obesity based on waist circumference measurement; three (2.5%) adolescents were obese based on subscapular skinfold thickness. According to the body mass index, the population studied was mainly eutrophic. The prevalence of fat redistribution, a characteristic of patients with HIV/AIDS under HAART, was low. We advise the development of further studies to assess the nutritional status of children and adolescents with HIV/AIDS using anthropometric measurements as well as computed tomography to detect fat redistribution.
Resumo:
This study investigated the relationship between iron deficiency/iron deficiency anaemia, assessed by several parameters, and blood lead concentration in children. This cross-sectional study involved 384 Brazilian children, aged 2-11 years, who lived near a lead-manipulating industry. Complete blood counts were obtained by an automated cell counter. Serum iron, total iron binding capacity (TIBC) and ferritin were determined respectively, by colorimetric, turbidimetric methods and chemiluminescence. Blood lead was measured by atomic absorption spectrophotometry. The impact of several parameters for assessment of iron status (haemoglobin, serum iron, TIBC, transferrin saturation, ferritin, red cell indices and red cell distribution width) and variables (gender, age, mother`s education, income, body mass index, iron intake, and distance from home to lead-manipulating industry) on blood lead concentration was determined by multiple linear regression. There were significant negative associations between blood lead and the distance from home to the lead-manipulating industry (P < 0.001), Hb (P = 0.019), and ferritin (P=0.023) (R(2)=0.14). Based on these results, further epidemiological studies are necessary to investigate the impact of interventions like iron supplementation or fortification, as an attempt to decrease blood lead in children. (C) 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.
Resumo:
Background & Aims: To investigate the effect of vitamin A supplementation on parameters of the immune system of vitamin A-deficient children. Methods: The study was carried out in four phases: 1) determination of serum retinol in 631 children from 36 to 83 months of age; 2) assessment of immunological markers [immunoglobulins and complement fractions, immunophenotyping of T and B lymphocytes, and natural killer (NK) cells], blood count, and serum ferritin of 52 vitamin A-deficient children (serum retinol <0.70 mu mol/L); 3) supplementation of the 52 deficient children with 200,000 IU of vitamin A; 4) determination of serum retinol and the immunological parameters 2 months after vitamin A supplementation. Results: Before vitamin A supplementation, 24.0% of the children were anemic and 4.3 %had reduced ferritin concentrations. There was no significant difference between mean values of retinol according to the presence/absence of anemia. The mean values of the humoral and cellular immunological parameters did not show a statistically significant difference before and after supplementation with vitamin A. Children with concomitant hypovitaminosis A and anemia presented a significant increase in absolute CD4 and CD8 T-cell counts after vitamin A supplementation (p < 0.05). Conclusion: Vitamin A had an effect on the recruitment of T and B lymphocytes to the circulation of children with hypovitaminosis A and anemia.
Resumo:
Background & aims: Pregnancy is a period characterized by high metabolic requirements and physiological changes in the female organism. During this period, Low body stores of vitamins and minerals including antioxidants can have adverse effects on the mother and foetus. This cross-sectional. study assessed plasma concentrations of ascorbic acid (AA) in 117 parturients admitted into a university hospital in S (a) over tildeo Paulo city, Brazil. Methods: The concentrations of AA were determined by the high performance liquid chromatographic method. Data concerning socioeconomic, demographic, obstetric and nutritional characteristics of the parturients were collected by a standardized questionnaire. Results: The prevalence of AA deficiency (< 22.7 mu mol/L) among the parturients was 30.8%. Mean plasma AA concentrations were lower in single/divorced women (27.84 +/- 3.48 mu mol./L) compared with married/single with partner women (34.78 +/- 1.85 mu mol/L) (p = 0.047). Blood AA concentrations were significantly correlated with per capita income (r = 0.36, p < 0.001) and vitamin C-rich food intake score (r = 0.42, p < 0.001). Conclusion: The high prevalence of hypovitaminosis C detected in this study is probably due to an inadequate intake of foods rich in vitamin C and tow income. We alert to the need for increasing the intake of vitamin C-rich foods through educational. programs, especially for tow income populations. (c) 2007 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.
Resumo:
The sensitivity of solar irradiance at the surface to the variability of aerosol intensive optical properties is investigated for a site (Alta Floresta) in the southern portion of the Amazon basin using detailed comparisons between measured and modeled irradiances. Apart from aerosol intensive optical properties, specifically single scattering albedo (omega(o lambda)) and asymmetry parameter (g(lambda)), which were assumed constant, all other relevant input to the model were prescribed based on observation. For clean conditions, the differences between observed and modeled irradiances were consistent with instrumental uncertainty. For polluted conditions, the agreement was significantly worse, with a root mean square difference three times larger (23.5 Wm(-2)). Analysis revealed a noteworthy correlation between the irradiance differences (observed minus modeled) and the column water vapor (CWV) for polluted conditions. Positive differences occurred mostly in wet conditions, while the differences became more negative as the atmosphere dried. To explore the hypothesis that the irradiance differences might be linked to the modulation of omega(o lambda) and g(lambda) by humidity, AERONET retrievals of aerosol properties and CWV over the same site were analyzed. The results highlight the potential role of humidity in modifying omega(o lambda) and g(lambda) and suggest that to explain the relationship seen between irradiances differences via aerosols properties the focus has to be on humidity-dependent processes that affect particles chemical composition. Undoubtedly, there is a need to better understand the role of humidity in modifying the properties of smoke aerosols in the southern portion of the Amazon basin.
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This article documents the addition of 512 microsatellite marker loci and nine pairs of Single Nucleotide Polymorphism (SNP) sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Alcippe morrisonia morrisonia, Bashania fangiana, Bashania fargesii, Chaetodon vagabundus, Colletes floralis, Coluber constrictor flaviventris, Coptotermes gestroi, Crotophaga major, Cyprinella lutrensis, Danaus plexippus, Fagus grandifolia, Falco tinnunculus, Fletcherimyia fletcheri, Hydrilla verticillata, Laterallus jamaicensis coturniculus, Leavenworthia alabamica, Marmosops incanus, Miichthys miiuy, Nasua nasua, Noturus exilis, Odontesthes bonariensis, Quadrula fragosa, Pinctada maxima, Pseudaletia separata, Pseudoperonospora cubensis, Podocarpus elatus, Portunus trituberculatus, Rhagoletis cerasi, Rhinella schneideri, Sarracenia alata, Skeletonema marinoi, Sminthurus viridis, Syngnathus abaster, Uroteuthis (Photololigo) chinensis, Verticillium dahliae, Wasmannia auropunctata, and Zygochlamys patagonica. These loci were cross-tested on the following species: Chaetodon baronessa, Falco columbarius, Falco eleonorae, Falco naumanni, Falco peregrinus, Falco subbuteo, Didelphis aurita, Gracilinanus microtarsus, Marmosops paulensis, Monodelphis Americana, Odontesthes hatcheri, Podocarpus grayi, Podocarpus lawrencei, Podocarpus smithii, Portunus pelagicus, Syngnathus acus, Syngnathus typhle,Uroteuthis (Photololigo) edulis, Uroteuthis (Photololigo) duvauceli and Verticillium albo-atrum. This article also documents the addition of nine sequencing primer pairs and sixteen allele specific primers or probes for Oncorhynchus mykiss and Oncorhynchus tshawytscha; these primers and assays were cross-tested in both species.
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The Human Respiratory Syncytial Virus (HRSV) fusion protein (F) was expressed in Escherichia call BL21A using the pET28a vector at 37 degrees C. The protein was purified from the soluble fraction using affinity resin. The structural quality of the recombinant fusion protein and the estimation of its secondary structure were obtained by circular dichroism. Structural models of the fusion protein presented 46% of the helices in agreement with the spectra by circular dichroism analysis. There are only few studies that succeeded in expressing the HRSV fusion protein in bacteria. This is a report on human fusion protein expression in E. call and structure analysis, representing a step forward in the development of fusion protein F inhibitors and the production of antibodies. (c) 2008 Elsevier Inc. All rights reserved.
Resumo:
The META cluster of Leishmania amazonensis contains both META1 and META2 genes, which are upregulated in metacyclic promastigotes and encode proteins containing the META domain. Previous studies defined META2 as a 48.0-kDa protein, which is conserved in other Leishmania species and in Trypanosoma brucei. In this work, we demonstrate that META2 protein expression is regulated during the Leishmania life cycle but constitutive in T. brucei. META2 protein is present in the cytoplasm and flagellum of L amazonensis promastigotes. Leishmania META2-null replacement mutants are more sensitive to oxidative stress and, upon heat shock, assume rounded morphology with shortened flagella. The increased susceptibility of null parasites to heat shock is reversed by extra-chromosomal expression of the META2 gene. Defective Leishmania promastigotes exhibit decreased ability to survive in macrophages. By contrast, META2 expression is decreased by 80% in RNAi-induced T. brucei bloodstream forms with no measurable effect on survival or resistance to heat shock. (C) 2010 Elsevier Inc. All rights reserved.
Resumo:
The advent of the Auger Engineering Radio Array (AERA) necessitates the development of a powerful framework for the analysis of radio measurements of cosmic ray air showers. As AERA performs ""radio-hybrid"" measurements of air shower radio emission in coincidence with the surface particle detectors and fluorescence telescopes of the Pierre Auger Observatory, the radio analysis functionality had to be incorporated in the existing hybrid analysis solutions for fluorescence and surface detector data. This goal has been achieved in a natural way by extending the existing Auger Offline software framework with radio functionality. In this article, we lay out the design, highlights and features of the radio extension implemented in the Auger Offline framework. Its functionality has achieved a high degree of sophistication and offers advanced features such as vectorial reconstruction of the electric field, advanced signal processing algorithms, a transparent and efficient handling of FFTs, a very detailed simulation of detector effects, and the read-in of multiple data formats including data from various radio simulation codes. The source code of this radio functionality can be made available to interested parties on request. (C) 2011 Elsevier B.V. All rights reserved.