76 resultados para 341.221


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T-cell proliferative hypo responsiveness, a hallmark of paracoccidioidomycosis immune responses, underlies host`s failure in controlling fungus spread, being reversible with antifungal treatment. The mechanisms leading to this hypoproliferation are not well known. Since costimulatory molecules have been shown to profoundly regulate T-cell immune responses, we investigated the hypothesis that the determinants of the responder versus tolerant state may be the regulated expression of, or signaling by, costimulatory molecules. Expression of CD80, CD86, CD28, CD152, ICOS and PD-1 costimulatory molecules were examined on T-cells and monocytes harvested from stimulated and unstimulated PBMC cultures of active paracoccidioidomycosis patients and healthy individuals cured of past paracoccidioidomycosis. Stimuli were gp43, the immunodominant component of Paracoccidioides brasiliensis, and a Candida antigen. While CD28 expression, critical for optimal T-cell activation, was comparable between patients and controls, CD152, PD-1 and ICOS, which preferentially deliver negative signaling, were overexpressed on patients` stimulated and unstimutated T-cells. PBMC cultures were carried out in presence of the respective blocking antibodies which, however, failed to restore T-cell proliferation. CD80 and CD86 were equally expressed on patients` and controls` monocytes, but overexpressed on patients` T-cells. Blockade with the respective blocking antibodies on day 4 of the culture also did not restore T-cell proliferation, while, on day 0, differentially inhibited Candida and gp43 responses, suggesting that different antigens require different costimulatory pathways for antigen presentation. Our data favors the hypothesis, raised from other foreign antigen models, that prolonged in vivo antigen exposure leads to an adaptive tolerance T-cell state which is hardly reverted in vitro. (C) 2008 Elsevier Inc. All rights reserved.

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We review here the advances in the understanding of the immunopathology of human paracoccidioidomycosis (PCM). Its investigation must take in account the intriguing natural history of the mycosis and its agent, providing clues to the mechanisms that lead to development of disease (unbalanced host-parasite relationship?) or to the clinically silent, chronic carrier state (balanced host-parasite relationship?), in exposed people living in endemic areas. Although the literature on this subject has progressed notably, the overall picture of what are the mechanisms of susceptibility or resistance continues to be fragmentary. Major advances were seen in the description of both the cytokines/chemokines associated to the different outcomes of the host-parasite interaction, and the fungus-monocyte/macrophage interaction, and cytokines released thereof by these cells. However, relatively few studies have attempted to modify, even in vitro, the patients` unbalanced immune reactivity. Consequently, the benefits of this improved knowledge did not yet reach clinical practice. Fortunately, the previous notion of the immune system as having two nearly independent arms, the innate and adaptive immunities, leaving a large gap between them, is now being overcome. Immunologists are now trying to dissect the connections between these two arms. This will certainly lead to more productive results. Current investigations should address the innate immunity events that trigger the IL-12/IFN-gamma axis and confer protection against PCM in those individuals living in endemic areas, who have been infected, but did not develop the mycosis.

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BACKGROUND - Squamous cell carcinomas of the skin of the bead are better treated with Mobs micrographic surgery which has the lowest recurrence rates and allows spare normal tissue. There are some characteristics of squamous cell carcinoma that can be related to a higher number of surgical stages. OBJECTIVE - To study characteristic of head squamous cell carcinoma that predicts a higher number of Mohs surgical stages. METHODS - A retrospective analysis of 51 squamous cell carcinomas of the bead treated with Mobs surgery was performed to determine risk factors for a higher number of surgical stages. The characteristics analyzed were clinical limits, morphology, recurrence, histological differentiation and size and compared to the number of surgical stages. The analysis was performed by Fisher`s exact test and multivariate logistic regression. RESULTS - The recurrent squamous cell carcinomas showed a tendency for a higher number of stages (p=0,081). The Odds Ratio for a higher number of Mobs stages was three for inaccurate limits; although not statistically significant, it corroborates clinical and previous publication. CONCLUSION - Clinical characteristics of squamous cell carcinoma as recurrence and inaccurate limits would not predict, but could indicate tendency of a higher number of Mobs micrographic surgery stages.

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The type of surface used for running can influence the load that the locomotor apparatus will absorb and the load distribution could be related to the incidence of chronic injuries. As there is no consensus on how the locomotor apparatus adapts to loads originating from running Surfaces with different compliance, the objective of this study was to investigate how loads are distributed over the plantar surface while running on natural grass and on a rigid surface-asphalt. Forty-four adult runners with 4 3 years of running experience were evaluated while running at 12 km/h for 40 m wearing standardised running shoes and Pedar insoles (Novel). Peak pressure, contact time and contact area were measured in six regions: lateral, central and medial rearfoot, midfoot, lateral and media] forefoot. The Surfaces and regions were compared by three ANOVAS (2 x 6). Asphalt and natural grass were statistically different in all variables. Higher peak pressures were observed on asphalt at the central (p < 0.001) [grass: 303.8(66.7) kPa; asphalt: 342.3(76.3) kPa] and lateral rearfoot (p < 0.001) [grass: 312.7(75.8) kPa: asphalt: 350.9(98.3) kPa] and lateral forefoot (p < 0.001) [grass: 221.5(42.9) kPa asphalt: 245.3(55.5) kPa]. For natural grass, contact time and contact area were significantly greater at the central rearfoot (p < 0.001). These results suggest that natural grass may be a Surface that provokes lighter loads on the rearfoot and forefoot in recreational runners. (C) 2008 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

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PURPOSE: To evaluate the impact of atypical retardation patterns (ARP) on detection of progressive retinal nerve fiber layer (RNFL) loss using scanning laser polarimetry with variable corneal compensation (VCC). DESIGN: Observational cohort study. METHODS: The study included 377 eyes of 221 patients with a median follow-up of 4.0 years. Images were obtained annually with the GDx VCC (Carl Zeiss Med, itec Inc, Dublin, California, USA), along with optic disc stereophotographs and standard automated perimetry (SAP) visual fields. Progression was determined by the Guided Progression Analysis software for SAP and by masked assessment of stereophotographs by expert graders. The typical scan score (TSS) was used to quantify the presence of ARPs on GDx VCC images. Random coefficients models were used to evaluate the relationship between ARP and RNFL thickness measurements over time. RESULTS: Thirty-eight eyes (10%) showed progression over time on visual fields, stereophotographs, or both. Changes in TSS scores from baseline were significantly associated with changes in RNFL thickness measurements in both progressing and nonprogressing eyes. Each I unit increase in TSS score was associated with a 0.19-mu m decrease in RNFL thickness measurement (P < .001) over time. CONCLUSIONS: ARPs had a significant effect on detection of progressive RNFL loss with the GDx VCC. Eyes with large amounts of atypical patterns, great fluctuations on these patterns over time, or both may show changes in measurements that can appear falsely as glaucomatous progression or can mask true changes in the RNFL. (Am J Ophthalmol 2009;148:155-163. (C) 2009 by Elsevier Inc. All rights reserved.)

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Background: The magnitude of risk conferred by the interaction between tobacco and alcohol use on the risk of head and neck cancers is not clear because studies have used various methods to quantify the excess head and neck cancer burden. Methods: We analyzed individual-level pooled data from 17 European and American case-control studies (11,221 cases and 16,168 controls) participating in the International Head and Neck Cancer Epidemiology consortium. We estimated the multiplicative interaction parameter (psi) and population attributable risks (PAR). Results: A greater than multiplicative joint effect between ever tobacco and alcohol use was observed for head and neck cancer risk (psi = 2.15; 95% confidence interval, 1.53-3.04). The PAR for tobacco or alcohol was 72% (95% confidence interval, 61-79%) for head and neck cancer, of which 4% was due to alcohol alone, 33% was due to tobacco alone, and 35% was due to tobacco and alcohol combined. The total PAR differed by subsite (64% for oral cavity cancer, 72% for pharyngeal cancer, 89% for laryngeal cancer), by sex (74% for men, 57% for women), by age (33% for cases < 45 years, 73% for cases > 60 years), and by region (84% in Europe, 51% in North America, 83% in Latin America). Conclusions: Our results confirm that the joint effect between tobacco and alcohol use is greater than multiplicative on head and neck cancer risk. However, a substantial proportion of head and neck cancers cannot be attributed to tobacco or alcohol use, particularly for oral cavity cancer and for head and neck cancer among women and among young-onset cases. (Cancer Epidemiol Biomarkers Prev 2009;18(2):541-50)

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Background: This study evaluated the effectiveness of adjunctive cognitive behavioral group therapy (CBGT) to prevent recurrence of episodes in euthymic patients with bipolar disorder. Methods: A randomized controlled single-blind trial was conducted with 50 patients with bipolar disorder types I and II followed up for at least 12 months in an outpatient service and whose disease was in remission. An experimental CBGT manual was developed and added to treatment as usual (TAU), and results were compared with TAU alone. Results: Intention-to-treat analysis showed that there was no difference between groups in terms of time until any relapse (Wilcoxon = 0.667; p = 0.414). When considering type of relapse, there was still no difference in either depressive (Wilcoxon = 3.328; p = 0.068) or manic episodes (Wilcoxon = 1.498; p = 0.221). Although occurrence of episodes also did not differ between groups (chi(2) = 0.28; p = 0.59), median time to relapse was longer for patients treated with CBGT compared to TAU (Mann-Whitney = -2.554; p = 0.011). Conclusions:Time to recurrence and number of episodes were not different in the group of patients treated with CBGT. However, median time to relapse was shorter in the TAU group. Studies with larger samples may help to clarify whether our CBGT approach prevents new episodes of bipolar disorder. Our findings also indicated that CBGT is feasible in euthymic patients with bipolar disorder and should be investigated in future studies. To our knowledge, this is the first publication of a controlled trial of CBGT for euthymic patients with bipolar disorder. Copyright (C) 2011 S. Karger AG, Basel

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There is a considerable interindividual variation in L-thyroxine [ 3,5,3`,5`-tetraiodo-l-thyronine (T(4))] dose required for thyrotropin (thyroid-stimulating hormone) suppression in patients with differentiated thyroid cancer. To investigate whether uridine diphosphate-glucuronosyl transferase 1A1 (UGT1A1)-mediated T(4) glucuronidation in liver affects T(4) dose, we genotyped 101 patients for the common UGT1A1-53(TA)(n) polymorphism and compared T(4) doses among patients having zero (5/6 and 6/6 genotypes), one (6/7 genotype), or two (7/7 and 7/8 genotypes) copies of the low-expression (TA) 7 and (TA) 8 alleles. A significant trend for decreasing T(4) dose with increasing number of copies of (TA)(7) and (TA)(8) (P = 0.037) and significant difference in T(4) dose across the UGT1A1-53(TA)(n) genotypes (P = 0.048) were observed, despite considerable overlap of T(4) doses among different genotypes. These results are consistent with reduced T(4) glucuronidation in patients with low-expression (TA) 7 and (TA) 8 alleles and provide the first evidence for association between UGT1A1-53(TA)(n) and T(4)-dose requirement for thyroid-stimulating hormone suppression in a natural clinical setting. Pharmacogenetics and Genomics 21: 341-343 (C) 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins. Pharmacogenetics and Genomics 2011, 21: 341-343

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Leishmaniasis is a parasitic disease caused by the intramacrophage protozoa Leishmania spp. and may be fatal if left untreated. Although pentavalent antimonials are toxic and their mechanism of action is unclear, they remain the first-line drugs for treatment of leishmaniasis. An effective therapy could be achieved by delivering antileishmanial drugs to the site of infection. Compared with free drugs, antileishmanial agent-containing liposomes are more effective, less toxic and have fewer adverse side effects. The aim of this study was to develop novel meglumine antimoniate (MA)-containing liposome formulations and to analyse their antileishmanial activity and uptake by macrophages. Determination of the 50% inhibitory concentration (IC(50)) values showed that MA-containing liposomes were >= 10-fold more effective than the free drug, with a 5-fold increase in selectivity index, higher activity and reduced macrophage toxicity. The concentration required to kill 100% of intracellular amastigotes was >= 40-fold lower when MA was encapsulated in liposomes containing phosphatidylserine compared with the free drug. Fluorescence microscopy analysis revealed increased uptake of fluorescent liposomes in infected macrophages after short incubation times compared with non-infected macrophages. In conclusion, these data suggest that MA encapsulated in liposome formulations is more effective against Leishmania-infected macrophages than the non-liposomal drug. Development of liposome formulations is a valuable approach to the treatment of infectious diseases involving the mononuclear phagocyte system. (C) 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.

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One of the challenges in screening for dementia in developing countries is related to performance differences due to educational and cultural factors. This study evaluated the accuracy of single screening tests as well as combined protocols including the Mini-Mental State Examination (MMSE), Verbal Fluency animal category (VF), Clock Drawing test (CDT), and Pfeffer Functional Activities Questionnaire (PFAQ) to discriminate illiterate elderly with and without Alzheimer`s disease (AD) in a clinical sample. Cross-sectional study with 66 illiterate outpatients diagnosed with mild and moderate AD and 40 illiterate normal controls. Diagnosis of AD was based on NINCDS-ADRDA. All patients were submitted to a diagnostic protocol including a clinical interview based on the CAMDEX sections. ROC curves area analyses were carried out to compare sensitivity and specificity for the cognitive tests to differentiate the two groups (each test separately and in two by two combinations). Scores for all cognitive (MMSE, CDT, VF) and functional assessments (PFAQ) were significantly different between the two groups (p < 0.001). The best screening instruments for this sample of illiterate elderly were the MMSE and the PFAQ. The cut-off scores for the MMSE, VF, CDT, and PFAQ were 17.5, 7.5, 2.5, and 11.5, respectively. The most sensitive combination came from the MMSE and PFAQ (94.1%), and the best specificity was observed with the combination of the MMSE and CDT (89%). Illiterate patients can be successfully screened for AD using well-known screening instruments, especially in combined protocols.

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Introduction Reduction of automatic pressure support based on a target respiratory frequency or mandatory rate ventilation (MRV) is available in the Taema-Horus ventilator for the weaning process in the intensive care unit (ICU) setting. We hypothesised that MRV is as effective as manual weaning in post-operative ICU patients. Methods There were 106 patients selected in the postoperative period in a prospective, randomised, controlled protocol. When the patients arrived at the ICU after surgery, they were randomly assigned to either: traditional weaning, consisting of the manual reduction of pressure support every 30 minutes, keeping the respiratory rate/tidal volume (RR/TV) below 80 L until 5 to 7 cmH(2)O of pressure support ventilation (PSV); or automatic weaning, referring to MRV set with a respiratory frequency target of 15 breaths per minute (the ventilator automatically decreased the PSV level by 1 cmH(2)O every four respiratory cycles, if the patient`s RR was less than 15 per minute). The primary endpoint of the study was the duration of the weaning process. Secondary endpoints were levels of pressure support, RR, TV (mL), RR/TV, positive end expiratory pressure levels, FiO(2) and SpO(2) required during the weaning process, the need for reintubation and the need for non-invasive ventilation in the 48 hours after extubation. Results In the intention to treat analysis there were no statistically significant differences between the 53 patients selected for each group regarding gender (p = 0.541), age (p = 0.585) and type of surgery (p = 0.172). Nineteen patients presented complications during the trial (4 in the PSV manual group and 15 in the MRV automatic group, p < 0.05). Nine patients in the automatic group did not adapt to the MRV mode. The mean +/- sd (standard deviation) duration of the weaning process was 221 +/- 192 for the manual group, and 271 +/- 369 minutes for the automatic group (p = 0.375). PSV levels were significantly higher in MRV compared with that of the PSV manual reduction (p < 0.05). Reintubation was not required in either group. Non-invasive ventilation was necessary for two patients, in the manual group after cardiac surgery (p = 0.51). Conclusions The duration of the automatic reduction of pressure support was similar to the manual one in the postoperative period in the ICU, but presented more complications, especially no adaptation to the MRV algorithm. Trial Registration Trial registration number: ISRCTN37456640

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Objective. The objective of this study was to conduct a cost-effectiveness analysis of a universal rotavirus vaccination program among children : 5 years of age in Brazil. Methods. Considering a hypothetical annual cohort of approximately 3 300 000 newborns followed over 5 years, a decision-tree model was constructed to examine the possible clinical and economic effects of rotavirus infection with and without routine vaccination of children. Probabilities and unit costs were derived from published research and national administrative data. The impact of different estimates for key parameters was studied using sensitivity analysis. The analysis was conducted from both healthcare system and societal perspectives. Results. The vaccination program was estimated to prevent approximately 1735 351 (54%) of the 3 210 361 cases of rotavirus gastroenteritis and 703 (75%) of 933 rotavirus-associated deaths during the 5-year period. At a vaccine price of 18.6 Brazilian reais (R$) per dose, this program would cost R$121 673 966 and would save R$38 536 514 in direct costs to the public healthcare system and R$71 778 377 in direct and indirect costs to society. The program was estimated to cost R$1 028 and R$1 713 per life-years saved (LYS)from the societal and healthcare system perspectives, respectively. Conclusions. Universal rotavirus vaccination was a cost-effective strategy for both perspectives. However, these findings are highly sensitive to diarrhea incidence rate, proportion of severe cases, vaccine coverage, and vaccine price.

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Transgenic plants are able to express molecules with antigenic properties. In recent years, this has led the pharmaceutical industry to use plants as alternative systems for the production of recombinant proteins. Plant-produced recominant proteins can have important applications in therapeutics, such as in the treatment of rheumatoid arthritis (RA). In this study, the mycobacterial HSP65 protein expressed in tobacco plants was found to be effective as a treatment for adjuvant-induced arthritis (AIA). We cloned the hsp65 gene from Mycobacterium leprae into plasmid pCAMBIA 2301 under the control of the double 35S promoter from cauliflower mosaic virus. Agrobacterium tumefaciens bearing the pChsp65 plasmid was used to transform tobacco plants. Incorporation of the hsp65 gene was confirmed by PCR, reverse transcription-PCR, histochemistry, and western blot analyses in several transgenic lines of tobacco plants. Oral treatment of AIA rats with the HSP65 protein allowed them to recover body weight and joint inflammation was reduced. Our results suggest a synergistic effect between the HSP65 expressed protein and metabolites presents in tobacco plants.

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Chronic ethanol Consumption and hypertension are related. In the current study we investigated whether changes in reactivity of the mesenteric arterial bed could account for the increased blood pressure associated with chronic ethanol intake. Changes in reactivity to phenylephrine and acetylcholine were investigated in the perfused mesenteric bed from rats treated with ethanol for 2 or 6 weeks and their age-matched controls. Mild hypertension was observed in chronically ethanol-treated rats. Treatment of rats for 6 weeks induced an increase in the contractile response of endothelium-intact mesenteric bed to phenylephrine, but not denuded rat mesenteric bed. The phenylephrine-induced increase in perfusion pressure was not altered after 2 weeks` treatment with ethanol. Moreover, acetylcholine-induced endothelium-dependent relaxation was reduced by ethanol treatment for 6 weeks, but not 2 weeks. Pre-treatment with indometacin, a cyclooxygenase inhibitor, reduced the maximum effect induced by phenylephrine (E-max) in endothelium-intact mesenteric bed from both control and ethanol-treated rats. No differences in the E-max values for phenylephrine were observed between groups in the presence of indometacin. L-NNA, a nitric oxide (NO) synthase (NOS) inhibitor, increased the E-max for phenylephrine in endothelium-intact mesenteric bed from control rats but not from ethanol-treated rats. Levels of endothelial NOS (eNOS) mRNA were not altered by chronic ethanol consumption. However, chronic ethanol intake strongly reduced eNOS protein levels in the mesenteric bed. This study shows that chronic ethanol consumption increases blood pressure and alters the reactivity of the mesenteric bed. Moreover, the increased vascular response to phenylephrine observed in the mesenteric bed is maintained by two mechanisms: an increased release of endothelial-derived vasoconstrictor prostanoids and a reduced modulatory action of endothelial NO, which seems to be associated with reduced post-transcriptional expression of eNOS.

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Aim Stapled haemorrhoidopexy may damage the anorectal musculature and its sensorimotor function. Most studies have not used a barostat for the measurement of compliance. This study aimed to investigate the effect of stapled haemorrhoidopexy on rectal compliance and sensitivity. Method After Ethical Committee approval, we studied 10 male patients (mean age 33.8 years) with third- or fourth-degree haemorrhoids. Rectal compliance and sensitivity were measured with a 600-ml bag and an electronic barostat. Volunteers were submitted to two consecutive rectal distension protocols, including continuous distension at 2, 4 and 6 months after stapled haemorrhoidopexy. Intraluminal volume and pressure were recorded, including the first rectal sensation, desire to defecate and onset of rectal pain. Another group of 10 male control patients (mean age 24.9 years) with pilonidal sinus and no haemorrhoids was also included in the study. Results Two months after stapled haemorrhoidopexy, rectal compliance decreased (7.1 +/- 0.2 vs 5.3 +/- 0.1, 6.4 +/- 0.1 vs 5.1 +/- 0.1 and 5.6 +/- 0.2 vs 4.7 +/- 0.1 ml/mmHg for first rectal sensation, desire to defecate and rectal pain, respectively; P < 0.05). The sensitivity threshold volume did not change for the first sensation but decreased significantly for the desier to defecate and pain (p < 0.05) (116.8 +/- 13.8 vs 148.4 +/- 14.61, 251.1 +/- 8.9 vs 185.8 +/- 8.6 and 293.3 +/- 16.6 vs 221.2 +/- 6.0 ml for first rectal sensation, desire to defecate and rectal pain, respectively). Four and 6 months after surgery, rectal compliance and sensitivity returned to levels similar to those in the basal period. Muscle tissue was found in only three of the 10 resected doughnuts. Controls remained without any change in rectal compliance and sensitivity. Conclusion Stapled haemorrhoidopexy transiently decreases rectal compliance and sensitivity threshold in young male patients.