977 resultados para Reaching


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This study was performed with the purpose of testing the hypothesis that the high prevalence of hepatitis C among former athletes is associated with their past use of injectable stimulants. The study involved the participation of 208 former professional and amateur soccer and basketball players from the region of Ribeirão Preto, Brazil, who answered a questionnaire regarding their exposure to risk factors, including the use of injectable stimulants in the time they were engaged in sporting activities. ELISA tests were used to detect infection by the hepatitis C virus, and confirmed with PCR and genotyping for the positive cases. It was observed that the former use of injectable stimulants was a practice disseminated among the participants (24.5%), reaching 50.8% in the professionals. The overall prevalence for hepatitis C was 7.2%, with values of 11% among professionals and 5.5% among amateurs. In both categories, the presence of infection was markedly higher among those who admitted past use of injectable stimulants when compared to those who denied such practice (36% and 0.8% among amateurs; 21.9% and 0% among professionals, respectively). Multivariate analysis showed that the use of those substances was the only variable associated with the risk of hepatitis C. This confirms previous observations, performed with reduced sample sizes and without comparison groups, which indicated that the use of injectable vitamins was a risk factor of hepatitis C among former athletes.

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BACKGROUND: Factors promoting the emergence of human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT) connection domain mutations and their effect on antiretroviral therapy (ART) are still largely undetermined. We investigated this matter by analyzing genotypic resistance tests covering 400 amino acid positions in the RT of HIV-1 subtype B viruses and corresponding treatment histories and laboratory measurements. METHODS: The emergence of connection domain mutations was studied in 334 patients receiving monotherapy or dual therapy with thymidine analogues at the time of the genotypic resistance test. Response to subsequent combination ART (cART) was analyzed using Cox regression for 291 patients receiving unboosted protease inhibitors. Response was defined by ever reaching an HIV RNA level <50 copies/mL during the first cART. RESULTS: The connection domain mutations N348I, R356K, R358K, A360V, and A371V were more frequently observed in ART-exposed than ART-naive patients, of which only N348I and A360V were nonpolymorphic (with a prevalence of <1.5% in untreated patients). N348I correlated with M184V and predominantly occurred in patients receiving lamivudine and zidovudine concomitantly. A360V was not associated with specific drug combinations and was found to emerge later than M184V or thymidine analogue mutations. Nonpolymorphic connection domain mutations were rarely detected in the absence of established drug resistance mutations in ART-exposed individuals (prevalence, <1%). None of the 5 connection domain mutations associated with treatment showed a statistically significant effect on response to cART. CONCLUSIONS: Despite their frequent emergence, connection domain mutations did not show large detrimental effects on response to cART. Currently, routine implementation of connection domain sequencing seems unnecessary for developed health care settings.

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We investigated whether an intervention mainly consisting of a signed agreement between patient and physician on the objectives to be reached, improves reaching these secondary prevention objectives in modifiable cardiovascular risk factors six-months after discharge following an acute coronary syndrome. BACKGROUND: There is room to improve mid-term adherence to clinical guidelines' recommendations in coronary heart disease secondary prevention, specially non-pharmacological ones, often neglected. METHODS: In CAM-2, patients discharged after an acute coronary syndrome were randomly assigned to the intervention or the usual care group. The primary outcome was reaching therapeutic objectives in various secondary prevention variables: smoking, obesity, blood lipids, blood pressure control, exercise and taking of medication. RESULTS: 1757 patients were recruited in 64 hospitals and 1510 (762 in the intervention and 748 in the control group) attended the six-months follow-up visit. After adjustment for potentially important variables, there were, between the intervention and control group, differences in the mean reduction of body mass index (0.5 vs. 0.2; p < 0.001) and waist circumference (1.6 cm vs. 0.6 cm; p = 0.05), proportion of patients who exercise regularly and those with total cholesterol below 175 mg/dl (64.7% vs. 56.5%; p = 0.001). The reported intake of medications was high in both groups for all the drugs considered with no differences except for statins (98.1% vs. 95.9%; p = 0.029). CONCLUSIONS: At least in the short term, lifestyle changes among coronary heart disease patients are achievable by intensifying the responsibility of the patient himself by means of a simple and feasible intervention.

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Objective. Mandibular osteoradionecrosis (ORN) is a serious complication of radiotherapy (RT) in head and neck cancer patients. The aim of this study was to analyze the incidence of and risk factors for mandibular ORN in squamous cell carcinoma (SCC) of the oral cavity and oropharynx.Study Design. Case series with chart review.Setting. University tertiary care center for head and neck oncology.Subjects and Methods. Seventy-three patients treated for stage I to IV SCC of the oral cavity and oropharynx between 2000 and 2007, with a minimum follow-up of 2 years, were included in the study. Treatment modalities included both RT with curative intent and adjuvant RT following tumor surgery. The log-rank test and Cox model were used for univariate and multivariate analyses.Results. The incidence of mandibular ORN was 40% at 5 years. Using univariate analysis, the following risk factors were identified: oral cavity tumors (P < .01), bone invasion (P < .02), any surgery prior to RT (P < .04), and bone surgery (P < .0001). By multivariate analysis, mandibular surgery proved to be the most important risk factor and the only one reaching statistical significance (P < .0002).Conclusion. Mandibular ORN is a frequent long-term complication of RT for oral cavity and oropharynx cancers. Mandibular surgery before irradiation is the only independent risk factor. These aspects must be considered when planning treatment for these tumors.

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This paper proposes a high-level reinforcement learning (RL) control system for solving the action selection problem of an autonomous robot. Although the dominant approach, when using RL, has been to apply value function based algorithms, the system here detailed is characterized by the use of direct policy search methods. Rather than approximating a value function, these methodologies approximate a policy using an independent function approximator with its own parameters, trying to maximize the future expected reward. The policy based algorithm presented in this paper is used for learning the internal state/action mapping of a behavior. In this preliminary work, we demonstrate its feasibility with simulated experiments using the underwater robot GARBI in a target reaching task

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The phlebotomine sand fly Lutzomyia velezi sp.nov. was described and illustrated from male specimens collected by light trap in the Reserva Natural Cañon del Río Claro in the Central Cordillera of the Colombian Andes. The new species belongs to the series sanguinaria of the subgenus Helcocyrtomyia, which is represented in Colombia by Lutzomyia cirrita, Lutzomyia hartmanni, Lutzomyia sanguinaria, Lutzomyia scorzai, Lutzomyia sp. of Pichindé and Lutzomyia tortura. The new species can be differentiated from others of the subgenus by the combination of the following characteristics: long antennal ascoids, reaching level of the papilla, coxite with a single basal seta and fifth palpomere longer than or equal to the sum of the lengths of the third and fourth palpomeres.

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The brain regulates all metabolic processes within the organism, and therefore, its energy supply is preserved even during fasting. However, the underlying mechanism is unknown. Here, it is shown, using (31)P-magnetic resonance spectroscopy that during short periods of hypoglycemia and hyperglycemia, the brain can rapidly increase its high-energy phosphate content, whereas there is no change in skeletal muscle. We investigated the key metabolites of high-energy phosphate metabolism as rapidly available energy stores by (31)P MRS in brain and skeletal muscle of 17 healthy men. Measurements were performed at baseline and during dextrose or insulin-induced hyperglycemia and hypoglycemia. During hyperglycemia, phosphocreatine (PCr) concentrations increased significantly in the brain (P = 0.013), while there was a similar trend in the hypopglycemic condition (P = 0.055). Skeletal muscle content remained constant in both conditions (P > 0.1). ANOVA analyses comparing changes from baseline to the respective glycemic plateau in brain (up to +15%) vs. muscle (up to -4%) revealed clear divergent effects in both conditions (P < 0.05). These effects were reflected by PCr/Pi ratio (P < 0.05). Total ATP concentrations revealed the observed divergency only during hyperglycemia (P = 0.018). These data suggest that the brain, in contrast to peripheral organs, can activate some specific mechanisms to modulate its energy status during variations in glucose supply. A disturbance of these mechanisms may have far-reaching implications for metabolic dysregulation associated with obesity or diabetes mellitus.

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This paper presents the morphological, histological and ultrastructural characteristics of Myxobolus oliveirai sp. nov., a parasite of the gill filaments in Brycon hilarii from the Brazilian Pantanal. Out of 216 B. hilariispecimens examined (126 wild and 90 cultivated), 38.1% of wild specimens (n = 48) were infected. The parasites form elongated plasmodia primarily in the tip of gill filaments, reaching about 3 mm in length. A thorough comparison with all the Myxobolus species described from South American hosts, as well as nearly all the Myxobolus species described so far is provided. Partial sequencing of the 18S rDNA gene revealed a total of 1,527 bp. The Myxobolus species parasite of B. hilarii did not match any of the Myxozoa available in GenBank. In the phylogenetic analysis, M. oliveirai sp. nov. composed a monophyletic group with eight other species: five species of Myxobolus parasites of mugilid fishes, two parasites of pangasiid and one of centrarchid. Infection prevalence values of the parasite revealed no significant differences between wet and dry seasons or between males and females. The importance of the infection to the farming of the host species is emphasized.

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Objective: To analyze the expression of peroxisome proliferator-activated receptor-γ1 and 2 (PPARγ1 and 2), 11β-hydroxysteroid dehydrogenase type 1 (11βHSD1), and leptin in adipose tissue (AT) of obese women during weight loss following Roux-en-Y gastric bypass (RYGB) and to compare these levels with those obtained in AT of nonobese subjects. Methods: Gene expression was determined by real-time RT-PCR prior to surgery and at 3, 6, and 12 months after RYGB. Results: All obese patients lost weight, reaching a mean BMI of 29.3 ± 1.0 kg/m(2) at 1 year after surgery (-33.9 ± 1.5% of their initial body weight). In obese subjects leptin and 11βHSD1 were over-expressed, whereas PPARγ1 was expressed at lower levels compared to controls. After surgery, leptin and 11βHSD1 gene expression decreased, whereas PPARγ1 expression increased. At 12 months after RYGB, these 3 genes had reached levels similar to the controls. In contrast, PPARγ2 gene expression was not different between groups and types of tissue and remained unchanged during weight loss. We found a positive correlation between BMI and levels of gene expression of leptin and 11βHSD1. Conclusion: Gene expression of leptin, PPARγ1, and 11βHSD1 in AT is modified in human obesity. This default is completely corrected by RYGB. Copyright © 2012 S. Karger GmbH, Freiburg.

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Background: In patients with cervical spine injury, a cervical collar may prevent cervical spine movements but renders tracheal intubation with a standard laryngoscope difficult if not impossible. We hypothesized that despite the presence of a semi-rigid cervical collar and with the patient's head taped to the trolley, we would be able to intubate all patients with the GlideScopeR and its dedicated stylet. Methods: 50 adult patients (ASA 1 or 2, BMI ≤35 kg/m2) scheduled for elective surgical procedures requiring tracheal intubation were included. After standardized induction of general anesthesia and neuromuscular blockade, the neck was immobilized with an appropriately sized semi-rigid Philadelphia Patriot® cervical collar, the head was taped to the trolley. Laryngoscopy was attempted using a Macintosh laryngoscope blade 4 and the modified Cormack Lehane grade was noted. Subsequently, laryngoscopy with the GlideScopeR was graded and followed by oro-tracheal intubation. Results: All patients were successfully intubated with the GlideScopeR and its dedicated stylet. The median intubation time was 50 sec [43; 61]. The modified Cormack Lehane grade was 3 or 4 at direct laryngoscopy. It was significantly reduced with the GlideScopeR (p <0.0001), reaching 2a in most of patients. Maximal mouth opening was significantly reduced with the cervical collar applied, 4.5 cm [4.5; 5.0] vs. 2.0 cm [1.8; 2.0] (p <0.0001). Conclusions: The GlideScope® allows oro-tracheal intubation in patients having their cervical spine immobilized by a semi-rigid collar and their head taped to the trolley. It furthermore decreases significantly the modified Cormack Lehane grade.

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The prevalence of hyponutrition in cystic fibrosis is high although it may vary according to the different studies. Detection of hyponutrition should be done by combining different methods, depending on their availability. However, the simplest and most validated criterion is to measure at each visit the weight (and height in children) in order to calculate the body mass index and categorizing hyponutrition according to absolute criteria: in adults < 18.5 kg/m(2), and in children as percentiles of the body mass index. Worsening of the nutritional status is directly related with the decrease in lung function parameters and it has been proposed as a morbidity (and even mortality) predictive factor in people with cystic fibrosis, independently of the level of pulmonary dysfunction. Exocrine pancreatic insufficiency is present is approximately 70-90% of the patients with cystic fibrosis and the genotype-phenotype correlation is high. Most of the patients with exocrine pancreatic insufficiency tolerate a high-fat diet provided that they are treated with pancreatic enzymes at appropriate doses. The prevalence of diabetes increases with age, reaching up 40% of the cases in patients older than 30 years. Clinical liver involvement is less prevalent (it approximately affects 1/3 of the patients). Other intestinal complications such as meconial ileus, gastroesophageal reflux, obstruction of the distal intestine, or fibrosing colon disease may also condition malnourishment. In patients with cystic fibrosis, a usual high-fat diet providing 120%-150% of the recommended calories is advised. If the nutritional goals are not achieved or maintained with diet modifications, artificial supplements may be added, although the recommendation for their use has not been endorsed by solid scientific evidences. The most frequently used preparations usually are polymeric or hypercaloric. The indications for enteral (through a tube, especially gastrostomy) or parenteral nutritional support are similar to those used in other pathologies. Dietary and nutritional control should be included in a multidisciplinary program allowing the improvement of the functional capacity and the quality of life and reducing, at least from a theoretical viewpoint, the morbimortality associated to malnourishment in these patients.

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Peroxisome proliferator-activated receptors (PPARs) compose a family of three nuclear receptors which act as lipid sensors to modulate gene expression. As such, PPARs are implicated in major metabolic and inflammatory regulations with far-reaching medical consequences, as well as in important processes controlling cellular fate. Throughout this review, we focus on the cellular functions of these receptors. The molecular mechanisms through which PPARs regulate transcription are thoroughly addressed with particular emphasis on the latest results on corepressor and coactivator action. Their implication in cellular metabolism and in the control of the balance between cell proliferation, differentiation and survival is then reviewed. Finally, we discuss how the integration of various intra-cellular signaling pathways allows PPARs to participate to whole-body homeostasis by mediating regulatory crosstalks between organs.

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Summary Points Brucellosis remains the commonest anthropozoonosis worldwide, and its treatment remains complex, requiring protracted administration of more than one antibiotic. In November 2006, a consensus meeting aimed at reaching a common specialist statement on the treatment of brucellosis was held in Ioannina, Greece under the auspices of the International Society of Chemotherapy and the Institute of Continuing Medical Education of Ioannina. The author panel suggests that the optimal treatment of uncomplicated brucellosis should be based on a six-week regimen of doxycycline combined either with streptomycin for 2–3 weeks, or rifampicin for six weeks. Gentamicin may be considered an acceptable alternative to streptomycin, while all other regimens/combinations should be considered second-line. The development of a common global therapeutic language for human brucellosis, and future, properly conducted clinical trials would definitely solve controversies regarding the disease.

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The understanding of sedimentary evolution is intimately related to the knowledge of the exact ages of the sediments. When working on carbonate sediments, age dating is commonly based on paleontological observations and established biozonations, which may prove to be relatively imprecise. Dating by means of strontium isotope ratios in marine bioclasts is the probably best method in order to precisely date carbonate successions, provided that the sample reflects original marine geochemical characteristics. This requires a precise study of the samples including its petrography, SEM and cathodoluminescence observations, stable carbon and oxygen isotope geochemistry and finally the strontium isotope measurement itself. On the Nicoya Peninsula (Northwestern Costa Rica) sediments from the Piedras Blancas Formation, Nambi Formation and Quebrada Pavas Formation were dated by the means of strontium isotope ratios measured in Upper Cretaceous Inoceramus shell fragments. Results have shown average 87Sr/86Sr values of 0.707654 (middle late Campanian) for the Piedras Blancas Formation, 0.707322 (Turonian-Coniacian) for the Nambi Formation and 0.707721 (late Campanian-Maastrichtian) for the Quebrada Pavas Formation. Abundant detrital components in the studied formations constitute a difficulty to strontium isotope dating. In fact, the fossil bearing sediments can easily contaminate the target fossil with strontium mobilized form basalts during diagenesis and thus the obtained strontium isotope ratios may be influenced significantly and so will the obtained ages. The new and more precise age assignments allow for more precision in the chronostratigraphic chart of the sedimentary and tectonic evolution of the Nicoya Peninsula, providing a better insight on the evolution of this region. Meteor Cruise M81 dredged shallow water carbonates from the Hess Rise and Hess Escarpment during March 2010. Several of these shallow water carbonates contain abundant Larger Foraminifera that indicates an Eocene-Oligocene age. In this study the strontium isotope values ranging from 0.707847 to 0.708238 can be interpreted as a Rupelian to Chattian age of these sediments. These platform sediments are placed on seamounts, now located at depths reaching 1600 m. Observation of sedimentologic characteristics of these sediments has helped to resolve apparent discrepancies between fossil and strontium isotope ages. Hence, it is possible to show that the subsidence was active during early Miocene times. On La Désirade (Guadeloupe France), the Neogene to Quaternary carbonate cover has been dated by microfossils and some U/Th-ages. Disagreements subsisted in the paleontological ages of the formations. Strontium isotope ratios ranging from 0.709047 to 0.709076 showed the Limestone Table of La Désirade to range from an Early Pliocene to Late Pliocene/early Pleistocene age. A very late Miocene age (87Sr/86Sr =0.709013) can be determined to the Detrital Offshore Limestone. The flat volcanic basement had to be eroded by wave-action during a long-term stable relative sea-level. Sediments of the Table Limestone on La Désirade show both low-stand and high-stand facies that encroach on the igneous basement, implying deposition during a major phase of subsidence creating accommodation space. Subsidence is followed by tectonic uplift documented by fringing reefs and beach rocks that young from the top of the Table Limestone (180 m) towards the present coastline. Strontium isotope ratios from two different fringing reefs (0.707172 and 0.709145) and from a beach rock (0.709163) allow tentative dating, (125ky, ~ 400ky, 945ky) and indicate an uplift rate of about 5cm/ky for this time period of La Désirade Island. The documented subsidence and uplift history calls for a new model of tectonic evolution of the area.

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In this report we present the growth process of the cobalt oxide system using reactive electron beam deposition. In that technique, a target of metallic cobalt is evaporated and its atoms are in-flight oxidized in an oxygen rich reactive atmosphere before reaching the surface of the substrate. With a trial and error procedure the deposition parameters have been optimized to obtain the correct stoichiometry and crystalline phase. The evaporation conditions to achieve the correct cobalt oxide salt rock structure, when evaporating over amorphous silicon nitride, are: 525 K of substrate temperature, 2.5·10-4 mbar of oxygen partial pressure and 1 Å/s of evaporation rate. Once the parameters were optimized a set of ultra thin film ranging from samples of 1 nm of nominal thickness to 20nm thick and bulk samples were grown. With the aim to characterize the samples and study their microstructure and morphology, X-ray diffraction, transmission electron microscopy, electron diffraction, energy dispersive X-ray spectroscopy and quasi-adiabatic nanocalorimetry techniques are utilised. The final results show a size dependent effect of the antiferromagnetic transition. Its Néel temperature becomes depressed as the size of the grains forming the layer decreases.