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1.
Phys Rev Lett ; 130(5): 051802, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800478

RESUMO

The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×10^{20} protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.4% statistical uncertainties. The double-differential cross section in final-state electron energy and angle is presented for the first time, together with the single-differential dependence on Q^{2} (squared four-momentum transfer) and energy, in the range 1 GeV≤E_{ν}<6 GeV. Detailed comparisons are made to the predictions of the GENIE, GiBUU, NEUT, and NuWro neutrino event generators. The data do not strongly favor a model over the others consistently across all three cross sections measured, though some models have especially good or poor agreement in the single differential cross section vs Q^{2}.

2.
Phys Rev Lett ; 127(20): 201801, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34860065

RESUMO

This Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions in the two NOvA detectors, at distances of 1 and 810 km from the beam source, is analyzed using an exposure of 12.51×10^{20} protons-on-target from the NuMI beam at Fermilab running in antineutrino mode. A total of 121 of neutral-current candidates are observed at the far detector, compared to a prediction of 122±11(stat.)±15(syst.) assuming mixing only between three active flavors. No evidence for ν[over ¯]_{µ}→ν[over ¯]_{s} oscillation is observed. Interpreting this result within a 3+1 model, constraints are placed on the mixing angles θ_{24}<25° and θ_{34}<32° at the 90% C.L. for 0.05 eV^{2}≤Δm_{41}^{2}≤0.5 eV^{2}, the range of mass splittings that produces no significant oscillations at the near detector. These are the first 3+1 confidence limits set using long-baseline accelerator antineutrinos.

4.
Phys Rev Lett ; 120(22): 221805, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29906174

RESUMO

We report on multinucleon effects in low momentum transfer (<0.8 GeV/c) antineutrino interactions on plastic (CH) scintillator. These data are from the 2010-2011 antineutrino phase of the MINERvA experiment at Fermilab. The hadronic energy spectrum of this inclusive sample is well described when a screening effect at a low energy transfer and a two-nucleon knockout process are added to a relativistic Fermi gas model of quasielastic, Δ resonance, and higher resonance processes. In this analysis, model elements introduced to describe previously published neutrino results have quantitatively similar benefits for this antineutrino sample. We present the results as a double-differential cross section to accelerate the investigation of alternate models for antineutrino scattering off nuclei.

5.
Phys Rev Lett ; 116(7): 071802, 2016 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-26943528

RESUMO

Two different nuclear-medium effects are isolated using a low three-momentum transfer subsample of neutrino-carbon scattering data from the MINERvA neutrino experiment. The observed hadronic energy in charged-current ν_{µ} interactions is combined with muon kinematics to permit separation of the quasielastic and Δ(1232) resonance processes. First, we observe a small cross section at very low energy transfer that matches the expected screening effect of long-range nucleon correlations. Second, additions to the event rate in the kinematic region between the quasielastic and Δ resonance processes are needed to describe the data. The data in this kinematic region also have an enhanced population of multiproton final states. Contributions predicted for scattering from a nucleon pair have both properties; the model tested in this analysis is a significant improvement but does not fully describe the data. We present the results as a double-differential cross section to enable further investigation of nuclear models. Improved description of the effects of the nuclear environment are required by current and future neutrino oscillation experiments.

6.
Cochrane Database Syst Rev ; (2): CD003147, 2006 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-16625571

RESUMO

BACKGROUND: Chest physiotherapy is widely prescribed to assist the clearance of airway secretions in people with cystic fibrosis (CF). Positive expiratory pressure (PEP) devices provide constant back pressure to the airways during expiration. This may improve clearance by building up gas behind mucus via collateral ventilation. Given the widespread use of PEP devices, there is a need to determine the evidence for their effect. OBJECTIVES: To determine the effectiveness and acceptability of PEP devices compared to other forms of physiotherapy as a means of improving mucus clearance and other outcomes in people with CF. SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising of references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. The electronic database CINAHL was also searched from 1982 to 2001. Most recent search of the Group's register: February 2006. SELECTION CRITERIA: Randomised controlled studies in which PEP was compared with any other form of physiotherapy in people with CF. DATA COLLECTION AND ANALYSIS: Two authors independently applied the inclusion and exclusion criteria to publications and assessed the quality of the included studies. MAIN RESULTS: Forty studies were identified and twenty-five studies involving 507 participants met the review inclusion criteria. Most included studies had low scores on a scale of study quality. Twenty of these studies involving 300 participants were cross-over in design. Data were not published in sufficient detail in most of these studies to perform meta-analysis.Forced expiratory volume in one second (FEV1) was the most frequently measured outcome. Single interventions or series of treatments continued for up to three months demonstrated no significant difference in effect between PEP and other methods of airway clearance on FEV1. Long-term studies had equivocal or conflicting results regarding the effect on FEV1. Participant preference was reported in nine studies. In all studies with an intervention period of at least one month, measures of participant preference were in favour of PEP. The results for the remaining outcome measures were not examined or reported in sufficient detail to provide any high level evidence. AUTHORS' CONCLUSIONS: There was no clear evidence that PEP was a more or less effective intervention overall than other forms of physiotherapy. There was limited evidence that PEP was preferred by participants compared to other techniques, but this finding is from studies of low quality.


Assuntos
Fibrose Cística/terapia , Muco/metabolismo , Respiração com Pressão Positiva/métodos , Fibrose Cística/complicações , Volume Expiratório Forçado , Humanos , Depuração Mucociliar , Ensaios Clínicos Controlados Aleatórios como Assunto , Capacidade Vital
7.
Eur Respir J ; 26(5): 904-8, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16264054

RESUMO

Sputum induction is used in the early identification of tuberculosis (TB) and pneumocystis infections of the lung. Although manual physiotherapy techniques to clear the airways are often incorporated in the sputum induction procedure, their efficacy in this setting is unknown. This randomised, crossover trial enrolled adults referred for sputum induction for suspected TB and pneumocystis infections of the lung. All participants underwent two sputum induction procedures, inhaling 3% saline via ultrasonic nebuliser. During one randomly allocated procedure, airway clearance techniques (chest wall percussion, vibration, huffing) were incorporated. In total, 59 participants completed the trial. The airway clearance techniques had no significant effect on how the test was tolerated, the volume expectorated or the quality of the sample obtained (assessed by the presence of alveolar macrophages). The techniques did not significantly affect how often the test identified a suspected organism, nor the sensitivity or specificity of sputum induction. In conclusion, the study was unable to demonstrate any effect of airway clearance techniques on the sputum induction procedure. The results provide some justification for not including airway clearance techniques as part of the sputum induction procedure.


Assuntos
Depuração Mucociliar , Estimulação Física/métodos , Infecções por Pneumocystis/diagnóstico , Infecções por Pneumocystis/microbiologia , Escarro/microbiologia , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Terapia Respiratória/métodos , Sensibilidade e Especificidade , Cloreto de Sódio , Manejo de Espécimes/métodos
8.
J Clin Microbiol ; 43(7): 3278-82, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16000448

RESUMO

The performances of the gelatin particle agglutination test (GPAT) and enzyme-linked immunosorbent assay (ELISA) for the diagnosis of strongyloidiasis with reference to the results of the agar plate culture technique (APCT) were evaluated with samples from 459 individuals from communities in northeast Thailand where strongyloidiasis is endemic. The prevalence of strongyloidiasis in five sample groups determined by GPAT varied between 29.3 and 61.5% (mean, 38.8%). ELISA and APCT, employed concurrently, gave lower prevalence rates of 27.5% (range, 21.6 to 42.1%) and 22.7% (range, 12.7 to 53.8%), respectively. By using APCT as the standard method, the sensitivity of GPAT was generally higher than that of ELISA (81 versus 73%). The specificity of GPAT was slightly lower than that of ELISA (74 versus 86%). The resulting GPAT titers exhibited positive linear relationships with the ELISA values (optical density at 490 nm) (P < 0.05), which suggests that the GPAT titer also reflects the levels of specific antibody comparable to those reflected by the ELISA values. Based on the relative ease and simplicity of use of the technique as well as the acceptable rates of sensitivity and specificity of the test, GPAT is more practical for screening for strongyloidiasis than the conventional ELISA.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Strongyloides stercoralis/imunologia , Estrongiloidíase/diagnóstico , Ágar , Testes de Aglutinação/métodos , Animais , Meios de Cultura , Ensaio de Imunoadsorção Enzimática , Gelatina , Humanos , Prevalência , Sensibilidade e Especificidade , Testes Sorológicos , Strongyloides stercoralis/isolamento & purificação , Estrongiloidíase/epidemiologia , Estrongiloidíase/parasitologia
9.
Genes Immun ; 6(1): 66-9, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15538390

RESUMO

In chronically HIV infected individuals, a number of functional B cell abnormalities have been described. However, the immediate changes that occur in the B cell compartment following viral exposure and how they affect the long-term course of infection are not well understood. We report the longitudinal analysis of B cell repertoires during early infection in untreated and treated individuals receiving highly active antiretroviral therapy (HAART). Analysis was based on IgG heavy chain gene utilization and CDR3 length measurement and relationship with CD4/CD8 counts, viral load, and total serum IgG, and anti-HIV antibodies levels. Repertoires were assessed at baseline and at weeks 2, 4, 12, 24, and 72 after initiation of therapy. The findings indicate a stable peripheral B cell repertoire during the first 72 weeks following infection, particularly in the HAART treated patients. A modest association between B cell repertoire integrity and viremia levels as well as treatment was detected.


Assuntos
Linfócitos B/imunologia , Regiões Determinantes de Complementaridade/imunologia , Rearranjo Gênico do Linfócito B/imunologia , Infecções por HIV/imunologia , HIV/imunologia , Adulto , Terapia Antirretroviral de Alta Atividade , Linfócitos B/patologia , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/patologia , Humanos , Masculino , Fatores de Tempo
10.
Eur J Clin Microbiol Infect Dis ; 24(1): 54-7, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15616837

RESUMO

Since the role of respiratory viruses in lung exacerbations of patients with cystic fibrosis has been hampered by the difficulty of detecting viruses in viscous sputum specimens, a multiplex reverse transcriptase PCR (RT-PCR) assay combined with colorimetric amplicon detection was tested for the identification of seven common respiratory viruses in the sputa of cystic fibrosis patients. Of 52 sputa from 38 patients, 12 (23%) samples from 12 patients were positive for a respiratory virus (4 for influenza B, 3 for parainfluenza 1, 3 for influenza A and 2 for respiratory syncytial virus). These results suggest that the RT-PCR method carried out on sputum may provide a convenient means of investigating the role of virus infection in lung exacerbations of cystic fibrosis patients.


Assuntos
Fibrose Cística/virologia , Infecções por Vírus Respiratório Sincicial/diagnóstico , Vírus Sinciciais Respiratórios/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Escarro/virologia , Adolescente , Adulto , Estudos de Casos e Controles , Fibrose Cística/diagnóstico , Feminino , Humanos , Incidência , Masculino , Probabilidade , Prognóstico , RNA Viral/análise , Testes de Função Respiratória , Infecções por Vírus Respiratório Sincicial/epidemiologia , Sensibilidade e Especificidade , Índice de Gravidade de Doença
11.
Clin Radiol ; 59(5): 431-8, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15081848

RESUMO

AIM: To investigate whether a lessened glucocorticoid cumulative dose would lead to a decreased incidence of femoral head osteonecrosis. METHODS: Newly transplanted in-patients (n = 49) underwent hip radiographs and magnetic resonance imaging (MRI) a mean of 17.0+/-4.3 (range 8-29) days after renal transplantation. For the 48 patients without evidence of prevalent osteonecrosis, imaging at a mean of 5.9+/-0.8 (range 4.8-8.7) months after renal transplantation was graded for presence/absence of femoral head osteonecrosis by two blinded radiologists. Sociodemographic and disease characteristics of patients were compared to identify potential associations with incident osteonecrosis. RESULTS: At 6-month follow-up, only two patients (4%) had osteonecrosis of the femoral head (three hips). The two primary radiologists had excellent agreement between osteonecrosis diagnosis (kappa coefficient=0.78). Both cases of a definite MRI diagnosis of osteonecrosis occurred in patients who were in the highest tertile of glucocorticoid dosage. CONCLUSION: Osteonecrosis was uncommon among a prospective cohort of renal transplant recipients within 6 months after engraftment.


Assuntos
Transplante de Rim , Osteonecrose/diagnóstico , Estudos de Coortes , Feminino , Necrose da Cabeça do Fêmur/diagnóstico , Articulação do Quadril , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia Computadorizada por Raios X/métodos
12.
Cochrane Database Syst Rev ; (1): CD003147, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14974007

RESUMO

BACKGROUND: Chest physiotherapy is widely prescribed to assist the clearance of airway secretions in people with cystic fibrosis (CF). Positive expiratory pressure (PEP) devices provide constant back pressure to the airways during expiration. This may improve clearance by building up gas behind mucus via collateral ventilation. Given the widespread use of PEP devices, there is a need to determine the evidence for their effect. OBJECTIVES: To determine the effectiveness and acceptability of PEP devices compared to other forms of physiotherapy as a means of improving mucus clearance and other outcomes in people with CF. SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group trials register comprising of references identified from comprehensive electronic database searches and handsearching of relevant journals and abstract books of conference proceedings. The electronic database CINAHL was also searched from 1982 to 2001. Most recent search of the Group's register: November 2003. SELECTION CRITERIA: Randomised controlled trials in which PEP was compared with any other form of physiotherapy in people with CF. DATA COLLECTION AND ANALYSIS: Two reviewers independently applied the inclusion and exclusion criteria to publications and assessed the quality of the included studies. MAIN RESULTS: Thirty-three studies were identified and twenty studies involving 429 participants met review inclusion criteria. Most included studies had low scores on a scale of study quality. Sixteen of these studies involving 257 participants were cross-over in design. Data were not published in sufficient detail in these studies to perform meta-analysis.Forced expiratory volume in one second (FEV1) was the most frequently measured outcome. Single interventions or series of treatments continued for up to one month demonstrated no significant difference in effect between PEP and other methods of airway clearance on FEV1. Long-term studies had equivocal or conflicting results regarding the effect on FEV1. Patient preference was reported in nine studies. In all studies with an intervention period of at least one month, measures of patient preference were in favour of PEP. The results for the remaining outcome measures were not examined or reported in sufficient detail to provide any high level evidence. REVIEWER'S CONCLUSIONS: There was no clear evidence that PEP was a more or less effective intervention overall than other forms of physiotherapy. There was limited evidence that PEP was preferred by participants compared to other techniques but this finding is from studies of low quality.


Assuntos
Fibrose Cística/terapia , Muco/metabolismo , Respiração com Pressão Positiva/métodos , Fibrose Cística/complicações , Humanos , Depuração Mucociliar , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Neurology ; 58(5): 709-16, 2002 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-11889232

RESUMO

BACKGROUND: Autoantibodies have been implicated in the development of chronic focal encephalitis (CFE) or Rasmussen's disease, a progressive and intractable form of epilepsy characterized by uncontrollable unilateral focal seizures, brain atrophy, and inflammation. OBJECTIVE: To investigate the origin and characteristics of the B cell population that trigger or sustain brain inflammation in patients with CFE. METHODS: The authors used immunoglobulin (Ig) complementary determining region 3 (CDR3)-size spectratyping and DNA sequencing to examine the rearranged IgG heavy chain (IgGH) transcript repertoire in resected brain samples from four patients with CFE. They also performed Western blotting on human and rat brain homogenates and immunostaining on a human neuronal cell line to test the reactivity of sera from patients with CFE. RESULTS: The authors observed substantial perturbations from the normal, unstimulated repertoire of immunoglobulin genes. Sequencing of randomly selected clones confirmed the restricted profile and provided evidence for somatic mutation patterns characteristic of antigen-specific stimulation. They also observed IgGVH-CDR3 sequence diversity among patients. When sera were assayed from patients with CFE for specificity against rat and human brain homogenates, heterogeneous reactivity patterns were detected among patients. Immunostaining of postmitotic human neuronal cells demonstrated reactivity of some patients' sera against neural antigens. CONCLUSIONS: These findings support an important role for clonally expanded B lymphocytes in some forms of epilepsy, but also indicate a wide spectrum of reactivity characteristic of antigenic heterogeneity.


Assuntos
Linfócitos B/imunologia , Encéfalo/imunologia , Regiões Determinantes de Complementaridade/genética , Encefalite/imunologia , Rearranjo Gênico do Linfócito B , Imunoglobulina G/genética , Animais , Linfócitos B/fisiologia , Encéfalo/patologia , Regiões Determinantes de Complementaridade/metabolismo , Encefalite/fisiopatologia , Feminino , Genes de Imunoglobulinas , Humanos , Imunoglobulina G/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Sprague-Dawley
14.
Dev Genes Evol ; 211(8-9): 377-87, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11685571

RESUMO

Previously, the only anuran amphibian known to regenerate the lens of the eye was Xenopus laevis. This occurs during larval stages through transdifferentiation of the outer cornea epithelium under control of factors presumably secreted by the neural retina. This study demonstrates that a distantly related species, X. tropicalis, is also able to regenerate lenses through this process. A transgenic line of X. tropicalis was used to examine the process of cornea-lens transdifferentiation in which green fluorescent protein (GFP) is expressed in differentiated lens cells under the control of the Xenopus gamma1-crystallin promoter element. Unlike X. laevis, the process of cornea-lens transdifferentiation typically occurs at a very low frequency in X. tropicalis due to the rapid rate at which the inner cornea endothelium heals to recover the pupillary opening. The inner cornea endothelium serves as a key physical barrier that normally prevents retinal signals from reaching the outer cornea epithelium. If this barrier is circumvented by implanting outer cornea epithelium of transgenic tadpoles directly into the vitreous chamber of non-transgenic X. tropicalis larval eyes, a higher percentage of cases formed lenses expressing GFP. Lenses were also formed if these tissues were implanted into X. laevis larval eyes, suggesting the same or similar inducing factors are present in both species. When pericorneal ectoderm and posteriolateral flank ectoderm were implanted into the vitreous chamber, only in rare cases did pericorneal ectoderm form lens cells. Thus, unlike the case in X. laevis, competence to respond to the inducing factors is tightly restricted to the cornea epithelium in X. tropicalis. As controls, all these tissues were implanted into the space located between the inner and outer corneas. None of these implants, including outer cornea epithelium, exhibited GFP expression. Thus, the essential inductive factors are normally contained within the vitreous chamber. One explanation why this type of lens regeneration is not seen in some other anurans could be due to the rapid rate at which the inner cornea endothelium heals to recover the pupillary opening once the original lens is removed. These findings are discussed in terms of the evolution of this developmental process within the anurans.


Assuntos
Diferenciação Celular , Córnea/citologia , Cristalino/citologia , Regeneração , Xenopus/fisiologia , Animais , Animais Geneticamente Modificados , Evolução Biológica , Linhagem da Célula , Córnea/fisiologia , Transplante de Córnea , Ectoderma/transplante , Epitélio/transplante , Genes Reporter/genética , Proteínas de Fluorescência Verde , Larva/genética , Larva/fisiologia , Cristalino/fisiologia , Cristalino/cirurgia , Proteínas Luminescentes , Microscopia de Fluorescência , Regiões Promotoras Genéticas/genética , Transgenes/genética , Corpo Vítreo/metabolismo , Xenopus/genética , Xenopus/crescimento & desenvolvimento , Xenopus laevis/crescimento & desenvolvimento , Xenopus laevis/fisiologia
15.
Exp Biol Med (Maywood) ; 226(7): 686-91, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11444105

RESUMO

Endothelial cells (EC) that form the inner lining of blood vessels remain quiescent in the normal adult vasculature except during angiogenesis and reendothelialization, which result in EC proliferation and migration. EC placed in culture at subconfluent density also undergo cell multiplication and movement. This report demonstrates that whereas in confluent EC in a compact monolayer, the EC-EC adhesion molecule platelet-endothelial cell adhesion molecule-1 (PECAM-1) is strongly expressed at cell borders, little or no PECAM-1 immunostaining is detected in sparse or migrating cultured EC. Consistent with this observation, steady-state PECAM-1 mRNA expression was much lower in subconfluent EC than in confluent EC. The absence of PECAM-1 expression in sparse EC appeared not to be linked to ability to proliferate, since PECAM-1 expression remained low even in the presence of nitric oxide (NO) or mitomycin C, agents that inhibit EC growth. However, another growth-inhibitory agent, TGF-beta 1, did not alter PECAM-1 staining. Based on these observations, it is hypothesized that cell-associated mechanical forces underlying cell tensegrity regulate PECAM-1 expression.


Assuntos
Divisão Celular , Movimento Celular , Endotélio Vascular/química , Endotélio Vascular/citologia , Regulação da Expressão Gênica , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Northern Blotting , Comunicação Celular , Células Cultivadas , Humanos , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , RNA Mensageiro/análise , Veias Umbilicais
16.
Blood ; 97(1): 214-20, 2001 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-11133763

RESUMO

The effects of early antiretroviral therapy on the peripheral CD8(+) T-cell population were assessed by sequentially determining the T-cell receptor (TCR) repertoire complexity in a cohort of 15 individuals recently diagnosed with human immunodeficiency virus infection. Analysis was based on quantitative TCR variable B gene (TCRBV) usage and complementary-determining region 3 length assessment. Repertories were assessed at baseline and at weeks 2, 4, 12, 24, and 72 after initiation of therapy. Early administration of highly active antiretroviral therapy has a positive effect on the preservation and homeostasis of the CD8(+) cell repertoire. Nevertheless, differences from average baseline and control TCR profiles and initial development of repertoire perturbations were observed. The findings suggest that additional therapeutic protocols will be required during primary infection to significantly prevent long-term erosion of the T-cell-mediated immune response.


Assuntos
Fármacos Anti-HIV/farmacologia , Linfócitos T CD8-Positivos/imunologia , Genes Codificadores dos Receptores de Linfócitos T/imunologia , Infecções por HIV/imunologia , HIV-1 , Adulto , Fármacos Anti-HIV/administração & dosagem , Linfócitos T CD4-Positivos , Linfócitos T CD8-Positivos/química , Linfócitos T CD8-Positivos/citologia , Estudos de Casos e Controles , Estudos de Coortes , Regiões Determinantes de Complementaridade/análise , Regiões Determinantes de Complementaridade/efeitos dos fármacos , Progressão da Doença , Feminino , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T/efeitos dos fármacos , Genes Codificadores dos Receptores de Linfócitos T/efeitos dos fármacos , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise , RNA Mensageiro/efeitos dos fármacos , Grupos Raciais , Receptores de Antígenos de Linfócitos T alfa-beta/análise , Receptores de Antígenos de Linfócitos T alfa-beta/efeitos dos fármacos , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Fatores de Tempo , Carga Viral
17.
Pac Health Dialog ; 8(1): 47-53, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12017836

RESUMO

Accurate health information is a key component in the development of health improvement strategies. This paper provides a discussion of the challenges in improving hospital information systems in relation to indigenous patients. Based on interviews with both staff and patients of a major city hospital complex, a picture emerges of the need for bottom-up approaches to understanding perceptions of identity. Indigenous patients were found to be generally comfortable about identifying themselves on hospital records (if asked), but were often not clear why such questions were asked. On the other hand hospital staff were often uncomfortable about asking and were equally not always clear why such information was needed. Issues of accurate hospital record administration are discussed in relation to the attitudes and perceptions of both staff and patients.


Assuntos
Sistemas de Informação Hospitalar/normas , Registros Hospitalares/normas , Havaiano Nativo ou Outro Ilhéu do Pacífico/classificação , Sistemas de Identificação de Pacientes/classificação , Atitude do Pessoal de Saúde , Atitude Frente a Saúde , Austrália , Coleta de Dados , Pesquisa sobre Serviços de Saúde , Humanos , Recursos Humanos em Hospital/psicologia
18.
Immunogenetics ; 51(4-5): 281-8, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10803840

RESUMO

Multiple sclerosis (MS) is a common disease of the central nervous system characterized by myelin loss and progressive neurological dysfunction. An underlying genetic susceptibility plays a clear role in the etiology of MS, likely acting in concert with an undefined environmental exposure. Full-genome screenings in multiplex MS families have identified several susceptibility regions, supporting a polygenic model for MS. Among these regions, evidence for weak linkage was observed at 3p/3cen suggesting the presence of an MS gene(s) of modest effect. Encoded here are two chemokine receptors, CCR5 and CCR2B. We examined the chromosome 3p21-24 region in 125 MS families (322 total affecteds and 200 affected sib-pairs), and performed genetic analyses of CCR5 and CCR2B loci and two nearby markers (D3S1289 and D3S1300) using both linkage- and association-based tests. No evidence of linkage to MS was observed for any of the tested markers. Affected relative-pair (SimIBD) and sib-pair analyses (ASPEX), and association testing (sib-TDT) for each locus were also not significant. However, age of onset was approximately 3 years later in patients carrying the CCR5delta32 deletion (P=0.018 after controlling for gender effects). Thus, chemokine receptor expression may be associated with differential disease onset in a subset of patients, and may provide a therapeutic target to modulate inflammatory demyelination.


Assuntos
Esclerose Múltipla/epidemiologia , Esclerose Múltipla/genética , Receptores CCR5/genética , Idade de Início , Cromossomos Humanos Par 10 , Cromossomos Humanos Par 3 , Feminino , Humanos , Escore Lod , Masculino , Esclerose Múltipla/etiologia , Fatores Sexuais , População Branca
19.
AIDS Res Hum Retroviruses ; 16(3): 183-90, 2000 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-10710206

RESUMO

The immunologic and virologic efficacy and safety of interferon a (IFN-alpha) administered in combination with zidovudine (ZDV) and zalcitabine (ddC) was evaluated in HIV-infected subjects with CD4+ cell counts between 300 and 500 cells/ml and no more than 14 weeks of prior antiretroviral therapy. A total of 256 subjects enrolled in an open-label, randomized controlled trial. Subjects were randomized equally into treatment groups. All subjects received ZDV and ddC, while half also receive IFN-alpha (3 MU subcutaneously every 24 hr). At 48 weeks the median average area under the curve minus baseline (AAUCMB) for plasma HIV-1 RNA for the two-drug group was -0.68 versus -0.75 log10 copies/ml for the IFN-alpha group (p = 0.046). Mean HIV-1 RNA changes from baseline to 48 weeks for these groups were -0.65 and -1.12 log10 copies/ml, respectively (p = 0.010). The median AAUCMB for CD4+ cell count for the two-drug group was 28 versus -1 cells/mm3 for the IFN-alpha group (p = 0.011). Neutropenia, anemia, and drug intolerance were more common in the IFN-alpha group. This study demonstrates that IFN-alpha inhibits HIV-1 replication but attenuates the CD4+ cell response to dual therapy with ZDV and ddC.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1 , Interferon-alfa/uso terapêutico , Adolescente , Adulto , Fármacos Anti-HIV/efeitos adversos , Contagem de Linfócito CD4 , Resistência Microbiana a Medicamentos , Feminino , Proteína do Núcleo p24 do HIV/sangue , Infecções por HIV/sangue , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue
20.
Br J Nutr ; 84(6): 791-802, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11177195

RESUMO

The present review attempts to provide an update of the scientific knowledge on the renal toxicity which occurs in human subjects as a result of chronic ingestion of low-level dietary Cd. It highlights important features of Cd toxicology and sources of uncertainty in the assessment of health risk due to dietary Cd. It also discusses potential mechanisms for increased susceptibility to Cd toxicity in individuals with diabetes. Exposure assessment on the basis of Cd levels in foodstuffs reveals that vegetables and cereals are the main sources of dietary Cd, although Cd is also found in meat, albeit to a lesser extent. Cd accumulates particularly in the kidney and liver, and hence offal contains relatively high amounts. Fish contains only small quantities of Cd, while crustaceans and molluscs may accumulate larger amounts from the aquatic environment. Data on Cd accumulation in human kidney and liver obtained from autopsy studies are presented, along with results of epidemiological studies showing the relationship between renal tubular dysfunction and kidney Cd burden. These findings suggest that a kidney Cd level of 50 microg/g wet weight is a maximum tolerable level in order to avoid abnormal kidney function. This renal Cd burden corresponds to a urinary Cd excretion of 2 microg/d. Accordingly, safe daily levels of Cd intake should be kept below 30 microg per person. Individual variations in Cd absorption and sensitivity to toxicity predicts that a dietary Cd intake of 30 microg/d may result in a slight renal dysfunction in about 1% of the adult population. The previous guideline for a maximum recommended Cd intake of 1 microg/kg body weight per d is thus shown to be too high to ensure that renal dysfunction does not occur as a result of dietary Cd intake.


Assuntos
Cádmio/toxicidade , Nefropatias/induzido quimicamente , Cádmio/administração & dosagem , Cádmio/farmacocinética , Nefropatias Diabéticas/metabolismo , Dieta , Análise de Alimentos , Humanos , Rim/metabolismo , Dose Máxima Tolerável
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