155 resultados para evoked potential
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This study was designed to investigate the feasibility of applying tone-ABRs in the nursery and neonatal intensive care unit (NICU), and to provide normative tone-ABR data from neonates. Normative tone-ABR latency data were determined. The study obtained intensity series of tone-ABRs from thirty preterm neonates and twenty fullterm neonates who had confirmed normal peripheral auditory function after passing both an OAE and ABR screening examination. ABRs were collected in response to 500, 1500, and 4000 Hz tone bursts at 70, 50, 30, and 20 dB nHL. Mean wave V latencies were compared between groups, ears, and by gender. Responses to tone bursts of 20 and 30 dB nHL were detected in 97% and 100% of all ears respectively, in addition to responses to the higher-intensity stimuli. Preterm neonates` ABRs showed significantly longer latencies than those of the full-term infants. Tone-ABR evaluation was found to be both feasible and reliable as a measure of auditory function in neonates.
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Liver transplantation increased 1.84-fold from 1988 to 2004. However, the number of patients on the waiting list for a liver increased 2.71-fold, from 553 to 1500. We used a mathematical equation to analyze the potential effect of using ABO-compatible living-donor liver transplantation (LDLT) on both our liver transplantation program and the waiting list. We calculated the prevalence distribution of blood groups (O, A, B, and AB) in the population and the probability of having a compatible parent or sibling for LDLT. The incidence of ABO compatibility in the overall population was as follows: A, 0.31; B, 0.133; O, 0.512; and AB, 0.04. The ABO compatibility for parent donors was blood group A, 0.174; B, 0.06; O, 0.152; and AB, 0.03; and for sibling donors was A, 0.121; B, 0.05; O, 0.354; and AB, 0.03. Use of LDLT can reduce the pressure on our liver transplantation waiting list by decreasing its size by at least 16.5% at 20 years after its introduction. Such a program could save an estimated 3600 lives over the same period.
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Liver transplantation was first performed at the University of Sao Paulo School of Medicine in 1968. Since then, the patient waiting list for liver transplantation has increased at a rate of 150 new cases per month. Liver transplantation itself rose 1.84-fold (from 160 to 295) from 1988 to 2004. However, the number of patients on the liver waiting list jumped 2.71-fold (from 553 to 1500). Consequently, the number of deaths on the liver waiting list moved to a higher level, from 321 to 671, increasing 2.09-fold. We have applied a mathematical model to analyze the potential impact of using a donation after cardiac death (DCD) policy on our liver transplantation program and on the waiting list. Five thousand one hundred people died because of accidents and other violent causes in our state in 2004; of these, only 295 were donors of liver grafts that were transplanted. The model assumed that 5% of these grafts would have been DCD. We found a relative reduction of 27% in the size of the liver transplantation waiting list if DCD had been used by assuming that 248 additional liver transplants would have been performed annually. In conclusion, the use of DCD in our transplantation program would reduce the pressure on our liver transplantation waiting list, reducing it by at least 27%. On the basis of this model, the projected number of averted deaths is about 41,487 in the next 20 years. Liver Transpl 14:1732-1736, 2008. (C) 2008 AASLD.
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Study design: A prospective, non-randomized clinical series trial. Objective: To evaluate the effect of autogenous undifferentiated stem cell infusion for the treatment of patients with chronic spinal cord injury (SCI) on somatosensory evoked potentials (SSEPs). Setting: A public tertiary hospital in Sao Paulo, Brazil. Methods: Thirty-nine consecutive patients with diagnosed complete cervical and thoracic SCI for at least 2 years and with no cortical response in the SSEP study of the lower limbs were included in the trial. The trial patients underwent peripheral blood stem cell mobilization and collection. The stem cell concentrate was cryopreserved and reinfused through arteriography into the donor patient. The patients were followed up for 2.5 years and submitted to SSEP studies to evaluate the improvement in SSEPs after undifferentiated cell infusion. Results: Twenty-six (66.7%) patients showed recovery of somatosensory evoked response to peripheral stimuli after 2.5 years of follow-up. Conclusion: The 2.5-year trial protocol proved to be safe and improved SSEPs in patients with complete SCI. Sponsorship: None. Spinal Cord (2009) 47, 733-738; doi: 10.1038/sc.2009.24; published online 31 March 2009
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Bipolar disorder (BD) is a chronic, severe, and highly disabling psychiatric disorder. Its underlying neurobiology remains largely unclear. A significant body of evidence indicates that inflammatory activation expressed by increased cytokines is relevant in its pathophysiology. IL-6 is one of the most important cytokines involved in the pathogenesis of immune and inflammatory disorders. Several studies recently showed increased levels of IL-6 in manic and depressive episodes and also during euthymia in subjects with BD. Tocilizumab is an IL-6 receptor antagonist being marketed for the treatment of rheumatoid arthritis and Castleman`s disease. In this article we discuss the possibility that tocilizumab may have a therapeutic role in treatment of BD through its anti-inflammatory action. (C) 2010 Elsevier Ltd. All rights reserved.
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Background/aim Regulation of apoptosis in non-alcoholic fatty liver disease (NAFLD) has been a theme of growing debate. Although no other study assessed the role of survivin in NAFLD, its expression has been reported in hepatic carcinogenesis because of other aetiological factors with relevant discrepancies. The aim of this study was to assess the pattern of survivin immunoexpression by tissue microarray along the whole spectrum of NAFLD, including non-alcoholic steatohepatitis (NASH)-related hepatocelular carcinoma (HCC). Methods Liver biopsies from 56 patients with NAFLD were evaluated: 18 with steatosis, 21 non-cirrhotic NASH, 10 NASH-related cirrhosis, seven NASH-related HCC, as compared with 71 HCC related to other causes and with 12 normal livers. Results Survivin immunoexpression in NAFLD was restricted to cytoplasm and was found to be progressively lower in advanced stages, including cirrhosis and HCC: steatosis vs NASH-related cirrhosis (P=0.0243); steatosis vs NASH-related HCC (P=0.0010); NASH vs NASH-related cirrhosis (P=0.0318); and NASH vs NASH-related HCC (P=0.0007), thus suggesting a deregulation of apoptosis from NAFLD towards HCC. Interestingly, survivin immunoreactivity in NASH-related HCC was also found to be significantly lower than in HCC related to other causes (P < 0.05). Remarkably, nuclear staining for survivin was not detected in any case of NAFLD, contrasting to its presence in all other cases of HCC. Conclusions Survivin immunoexpression in NASH-related HCC is herein originally found substantially different than in HCC related to other causes, thus requiring further studies to elucidate the role of survivin in human NAFLD progression.
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In Brazil, sugarcane fields are often burned to facilitate manual harvesting, and this burning causes environmental pollution from the large amounts of soot released into the atmosphere. This material contains numerous organic compounds such as PAHs. In this study, the concentrations of PAHs in two particulate-matter fractions (PM(2.5) and PM(10)) in the city of Araraquara (SE Brazil, with around 200,000 inhabitants and surrounded by sugarcane plantations) were determined during the sugarcane harvest (HV) and non-harvest (NHV) seasons in 2008 and 2009. The sampling strategy included four campaigns, with 60 samples in the NHV season and 220 samples in the HV season. The PM(2.5) and PM(10) fractions were collected using a dichotomous sampler (10 L min(-1), 24 h) with Teflon (TM) filters. The filter sets were extracted (ultrasonic bath with hexane/acetone (1:1 v/v)) and analyzed by HPLC/Fluorescence. The median concentration for total PAHs (PM(2.5) in 2009) was 0.99 ng m(-3) (NHV) and 3.3 ng m(-3) (HV). In the HV season, the total concentration of carcinogenic PAHs (benz(a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene, and benzo(a)pyrene) was 5 times higher than in the NHV season. B(a)P median concentrations were 0.017 ng m(-3) and 0.12 ng m(-3) for the NHV and HV seasons, respectively. The potential cancer risk associated with exposure through inhalation of these compounds was estimated based on the benzo[a]pyrene toxic equivalence (BaP(eq)), where the overall toxicity of a PAR mixture is defined by the concentration of each compound multiplied by its relative toxic equivalence factor (TEF). BaP(eq) median (2008 and 2009 years) ranged between 0.65 and 1.0 ng m(-3) and 1.2-1.4 ng m(-3) for the NHV and HV seasons, respectively. Considering that the maximum permissible BaPeq in ambient air is 1 ng m(-3), related to the increased carcinogenic risk, our data suggest that the level of human exposure to PAHs in cities surrounded by sugarcane crops where the burning process is used is cause for concern. (C) 2010 Published by Elsevier Ltd.
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Overexpression of kallikrein 7, a proteolytic enzyme important for epithelial cell shedding, may be causally involved in carcinogenesis, particularly in tumor metastasis and invasion. In this study, we have evaluated hK7 (human kallikrein 7) protein levels by immunohistochemistry in 367 cervical histological samples including 35 cases of cervicitis, 31 low-grade cervical intraepithelial neoplasia, 51 high-grade cervical intraepithelial neoplasia (H-SIL), 197 squamous cervical carcinomas (SCC) and 53 cervical adenocarcinomas. We have observed that hK7 staining increased with the severity of cervical disease. Intense hK7 staining was found in 15.2% of cervicitis samples, in contrast to 55% of H-SIL and 68% of SCC. Moreover, 92.5% of adenocarcinomas also exhibited intense hK7 staining. Differences in the expression of hK7 could potentially be used as a biomarker for the characterization of different stages of cervical disease.
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Introduction. The hippocampal formation is a specific structure in the brain where neurogenesis occurs throughout adulthood and in which the neuronal cell loss causes various demential states. The main goal of this study was to verify whether fetal neural progenitor cells (NPCs) from transgenic rats expressing green fluorescent protein (GFP) retain the ability to differentiate into neuronal cells and to integrate into the hippocampal circuitry after transplantation. Methods. NPCs were isolated from E14 (gestational age: 14 days postconception) transgenic-Lewis and wild-type Sprague-Dawley rat embryos. Wild-type and transgenic cells were expanded and induced to differentiate into a neuronal lineage in vitro. Immunocytochemical and electrophysiological analysis were performed in both groups. GFP-expressing cells were implanted into the hippocampus and recorded electrophysiologically 3 months thereafter. Immunohistochemical analysis confirmed neuronal differentiation, and the yield of neuronal cells was determined stereologically. Results. NPCs derived from wild-type and transgenic animals are similar regarding their ability to generate neuronal cells in vitro. Neuronal maturity was confirmed by immunocytochemistry and electrophysiology, with demonstration of voltage-gated ionic currents, firing activity, and spontaneous synaptic currents. GFP-NPCs were also able to differentiate into mature neurons after implantation into the hippocampus, where they formed functional synaptic contacts. Conclusions. GFP-transgenic cells represent an important tool in transplantation studies. Herein, we demonstrate their ability to generate functional neurons both in vitro and in vivo conditions. Neurons derived from fetal NPCs were able to integrate into the normal hippocampal circuitry. The high yield of mature neurons generated render these cells important candidates for restorative approaches based on cell therapy.
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Background: The role of platelets in hemostasis is well known, but few papers have reported their role in pain and edema induced by inflammatory agents. Objective: To evaluate the role of circulating platelets in the local injury induced by two diverse inflammatory agents, Bothrops jararaca venom (Bjv) and carrageenan. Methods: Rats were (i) rendered thrombocytopenic by administration of polyclonal anti-rat platelet IgG (ARPI) or busulfan, or (ii) treated with platelet inhibitors (aspirin or clopidogrel). Edema formation, local hemorrhage and the pain threshold were assessed after intraplantar injection of Bjv or carrageenan in rat hind paws. Additionally, whole platelets or platelet releasate were tested whether they directly induced hyperalgesia. Results: Platelet counts were markedly diminished in rats administered with either ARPI (+/- 88%) or busulfan (+/- 96%). Previous treatment with ARPI or busulfan slightly reduced edema induced by Bjv or carrageenan. Injection of Bjv, but not of carrageenan, induced a statistically significance increase in hemorrhage in the hind paws of thrombocytopenic rats. Remarkably, hyperalgesia evoked by Bjv or carrageenan was completely blocked in animals treated with ARPI or busulfan, or pre-treated with aspirin or clopidogrel. On the other hand, intraplantar administration of whole platelets or platelet releasate evoked hyperalgesia, which was inhibited by pre-incubation with alkaline phosphatase. Conclusions: Thrombocytopenia or inhibition of platelet function drastically reduced hyperalgesia induced by injection of carrageenan or Bjv; moreover, platelets per se secrete phosphorylated compounds involved in pain mediation. Thus, blood platelets are crucial cells involved in the pain genesis, and their role therein has been underestimated.
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P>We have developed a two-step PCR assay that amplifies a region of the ceja-1 sequence that is specific for virulent strains of Paracoccidioides brasiliensis. An internal region of the ceja-1 sequence was chosen for designing primers that were utilised in a single tube heminested PCR protocol to amplify DNA from six virulent strains. PCR specificity was determined by the absence of amplified products with genomic DNA from four non-virulent strains of P. brasiliensis and from eight fungal pathogens, one bacterium, two protozoa, one worm and mouse and human genomic DNA (leucocytes). The fact that the PCR product was only obtained with the genetic material from virulent isolates of P. brasiliensis suggested that this partial amplified sequence might be a marker of virulence for this fungus. The diagnostic potential of this PCR was confirmed by the successful amplification of this fragment with genomic DNA obtained in lymph node aspirate from a patient with paracoccidioidomycosis.
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Replication-defective adenoviruses have been utilized as candidate HIV vaccine vectors Few studies have described the international epidemiology of pre-existing immunity to adenoviruses We enrolled 1904 participants in a cross-sectional serological survey at seven sites in Africa, Brazil, and Thailand to assess neutralizing antibodies (NA) for adenovirus types Ad5, Ad6, Ad26 and Ad36 Clinical trial samples were used to assess NA titers from the US and Europe The proportions of participants that were negative were 14 8%(Ad5), 31 5%(Ad6),41 2%(Ad26) and 53.6% (Ad36) Adenovirus NA titers varied by geographic location and were higher in non-US and non-European settings, especially Thailand In multivariate logistic regression analysis, geographic setting (non-US and non-European settings) was statistically significantly associated with having higher Ad5 titers, participants from Thailand had the highest odds of having high Ad5 titers (adjusted OR = 3 53,95% CI 224,557) Regardless of location. titers of Ad5NA were the highest and Ad36 NA were the lowest Coincident Ad5/6 titers were lower than either Ad5 or Ad6 titers alone Understanding pre-existing immunity to candidate vaccine vectors may contribute to the evaluation of vaccines in international populations (C) 2009 Published by Elsevier Ltd
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Introduction: The delay in the diagnosis of infections can be deleterious in renal transplant recipients. Thus, laboratory tests leading to an earlier diagnosis are very useful for these patients. Purpose: To assess the behavior of C-reactive protein (CRP) in renal transplant recipients with a diagnosis of cytomegalovirus (CMV) infection, tuberculosis (TB) and bacterial infection (BI). Methods: A retrospective analysis of 129 patients admitted at our hospital, from 2006 to 2008 because of CMV, TB or BI, was carried out. Appropriate statistical analysis was done and values were expressed as medians, range. Results: When CRP levels were compared among the groups with CMV disease, TB or BI, the group with CMV disease presented lower levels of CRP (18.4 mg/L, 0.28-44 mg/L) than the TB and BI (p < 0.05) groups. The area under the receiver-operating characteristics curve, distinguishing CMV disease from TB/BI, was 0.96 (p < 0.0001), resulting in 100% sensitivity and 90.63% specificity to detect CMV disease when CRP < 44.5 mg/L. The subgroup analysis of CMV infection showed increasing levels of CRP (0.28, 16 and 29.5 mg/L) in the asymptomatic, symptomatic and invasive disease subgroups, respectively (p < 0.05). Conclusion: The measurement of CRP levels may be a useful tool for differentiating CMV infection from the other types (bacterial or TB) of infection in kidney transplant recipients.
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Models of warped extra dimensions with custodial symmetry usually predict the existence of a light Kaluza-Klein fermion arising as a partner of the right-handed top quark, sometimes called light custodians which we will denote (b) over tilde (R). The production of these particles at the LHC can give rise to multi-W events which could be observed in same-sign dilepton channels, but its mass reconstruction is challenging. In this paper we study the possibility of finding a signal for the pair production of this new particle at the LHC focusing on a rarer, but cleaner decay mode of a light custodian into a Z boson and a b-quark. In this mode it would be possible to reconstruct the light custodian mass. In addition to the dominant standard model QCD production processes, we include the contribution of a Kaluza-Klein gluon first mode. We find that (b) over tilde (R) stands out from the background as a peak in the bZ invariant mass. However, when taking into account only the electronic and muonic decay modes of the Z boson and b-tagging efficiencies, the LHC will have access only to the very light range of masses, m((b) over tilde) = O(500) GeV.
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Sepsis is the systemic inflammatory response syndrome secondary to a local infection. Septic shock, the severe complication of sepsis associated with refractory hypotension, is frequently a near-fatal condition requiring prompt diagnosis and management. Although the recent years have been associated with considerable improvements in the knowledge of the pathophysiology of the disease and remarkable advances have been achieved in sepsis treatment, the morbidity and mortality of this disease are still unacceptably high. In this review, we will briefly discuss the ongoing standard treatment of septic shock and describe novel potential therapies, aiming to improve hemodynamic support and/or control inflammatory response in sepsis. These therapies were associated with benefits in experimental studies and have been tested or are currently under testing in randomized controlled studies with septic patients.