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1.
N Z Med J ; 126(1375): 71-85, 2013 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-23824026

RESUMO

AIMS: New Zealand's ageing population threatens the financial sustainability of our current model of health service delivery. The Canterbury Health, Ageing and Life Course (CHALICE) study aims to develop a comprehensive and flexible database of important determinants of health to inform new models. This paper describes the design, methodology, and first 300 participants of CHALICE. METHODS: Commencing August 2010, CHALICE is a multidisciplinary prospective random cohort study and biobank of 1,000 Canterbury adults aged 49-51 years at inception, stratified by self-identified Maori (n=200) and non-Maori (n=800) ethnicity. Assessment covers sociodemographic, physical, cognition, mental health, clinical history, family and social, cardiovascular, and lifestyle domains. Detailed follow-up assessment occurs every 5 years, with a brief postal follow-up assessment undertaken annually. RESULTS: For the first 300 participants (44 Maori, 256 non-Maori), the participation rate is 63.7%. Overall, 53.3% of participants are female, 75.3% are living in married or de facto relationships, and 19.0% have university degrees. These sociodemographic profiles are comparable with the 2006 Census, Canterbury region, 50-54 years age group percentages (50.7%, 77.2%, and 14.3%, respectively). CONCLUSIONS: CHALICE has been designed to provide quality data that will inform policy development and programme implementation across a broad spectrum of health indicators.


Assuntos
Envelhecimento , Nível de Saúde , Inquéritos Epidemiológicos , Envelhecimento/etnologia , Doença Crônica/etnologia , Feminino , Seguimentos , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Acessibilidade aos Serviços de Saúde , Disparidades nos Níveis de Saúde , Disparidades em Assistência à Saúde , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Havaiano Nativo ou Outro Ilhéu do Pacífico , Nova Zelândia , Estudos Prospectivos , Projetos de Pesquisa , Fatores Socioeconômicos
2.
Blood ; 119(20): 4645-55, 2012 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-22490332

RESUMO

True long-term nonprogressors (LTNPs)/elite controllers (ECs) maintain durable control over HIV replication without antiretroviral therapy. Herein we describe 4 unique persons who were distinct from conventional LTNPs/ECs in that they had extraordinarily low HIV burdens and comparatively weak immune responses. As a group, typical LTNPs/ECs have unequivocally reactive HIV-1 Western blots, viral loads below the lower threshold of clinical assays, low levels of persistent viral reservoirs, an over-representation of protective HLA alleles, and robust HIV-specific CD8(+) T-cell responses. The 4 unique cases were distinguished from typical LTNPs/ECs based on weakly reactive Western blots, undetectable plasma viremia by a single copy assay, extremely low to undetectable HIV DNA levels, and difficult to isolate replication-competent virus. All 4 had at least one protective HLA allele and CD8(+) T-cell responses that were disproportionately high for the low antigen levels but comparatively lower than those of typical LTNPs/ECs. These unique persons exhibit extraordinary suppression over HIV replication, therefore, higher-level control than has been demonstrated in previous studies of LTNPs/ECs. Additional insight into the full spectrum of immune-mediated suppression over HIV replication may enhance our understanding of the associated mechanisms, which should inform the design of efficacious HIV vaccines and immunotherapies.


Assuntos
Infecções por HIV/imunologia , Sobreviventes de Longo Prazo ao HIV , HIV-1/imunologia , Adulto , Feminino , Infecções por HIV/sangue , Infecções por HIV/virologia , Soropositividade para HIV/imunologia , Soropositividade para HIV/virologia , HIV-1/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Carga Viral , Replicação Viral/imunologia , Replicação Viral/fisiologia
3.
Blood ; 119(13): 3105-12, 2012 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-22219223

RESUMO

Since the introduction of highly active antiretroviral therapies (ART), the prognosis for HIV-1 patients has improved immensely. However, approximately 25% of patients can experience a variety of inflammatory symptoms that are collectively known as immune reconstitution inflammatory syndrome (IRIS). Studying the etiology and immunopathology of IRIS has been hampered by the fact that the symptoms and associated opportunistic infections are highly varied. We hypothesized that there is a common mechanism underlying IRIS pathogenesis and investigated a patient group with IRIS related to different pathogens. Functional and phenotypic characterization of PBMC samples was performed by polychromatic flow cytometry after in vitro stimulation with relevant antigenic preparations. In most patients, IRIS events were characterized by the robust increase of preexisting polyfunctional, highly differentiated effector CD4(+) T-cell responses that specifically targeted the antigens of the underlying co-infection. T-cell responses to HIV-1 or other underlying infections were not affected and did not differ between IRIS and non-IRIS patients. These data suggest that patients with IRIS do not have a generalized T-cell dysfunction; instead, IRIS represents a dysregulated CD4(+) T-cell response against residual opportunistic infection antigen. These studies were registered at www.clinical-trials.gov as NCT00557570 and NCT00286767.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Proliferação de Células , Infecções por HIV/imunologia , HIV-1/imunologia , Síndrome Inflamatória da Reconstituição Imune/imunologia , Infecções Oportunistas Relacionadas com a AIDS/sangue , Infecções Oportunistas Relacionadas com a AIDS/etiologia , Infecções Oportunistas Relacionadas com a AIDS/imunologia , Adulto , Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Feminino , Infecções por HIV/sangue , Infecções por HIV/complicações , Infecções por HIV/virologia , HIV-1/patogenicidade , HIV-1/fisiologia , Humanos , Síndrome Inflamatória da Reconstituição Imune/sangue , Síndrome Inflamatória da Reconstituição Imune/etiologia , Síndrome Inflamatória da Reconstituição Imune/virologia , Estudos Longitudinais , Masculino , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Carga Viral
4.
Environ Sci Technol ; 45(19): 8233-40, 2011 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-21842879

RESUMO

Determination of the source and form of metals in house dust is important to those working to understand human and particularly childhood exposure to metals in residential environments. We report the development of a synchrotron microprobe technique for characterization of multiple metal hosts in house dust. We have applied X-ray fluorescence for chemical characterization and X-ray diffraction for crystal structure identification using microfocused synchrotron X-rays at a less than 10 µm spot size. The technique has been evaluated by application to archived house dust samples containing elevated concentrations of Pb, Zn, and Ba in bedroom dust, and Pb and As in living room dust. The technique was also applied to a sample of soil from the corresponding garden to identify linkages between indoor and outdoor sources of metals. Paint pigments including white lead (hydrocerussite) and lithopone (wurtzite and barite) are the primary source of Pb, Zn, and Ba in bedroom dust, probably related to renovation activity in the home at the time of sampling. The much lower Pb content in the living room dust shows a relationship to the exterior soil and no specific evidence of Pb and Zn from the bedroom paint pigments. The technique was also successful at confirming the presence of chromated copper arsenate treated wood as a source of As in the living room dust. The results of the study have confirmed the utility of this approach in identifying specific metal forms within the dust.


Assuntos
Poeira/análise , Metaloides/isolamento & purificação , Metais/isolamento & purificação , Técnicas de Sonda Molecular , Extração em Fase Sólida/métodos , Síncrotrons , Arseniatos/química , Canadá , Humanos , Chumbo/isolamento & purificação , Solo/química , Espectrometria por Raios X , Madeira/química , Difração de Raios X , Zinco/isolamento & purificação
5.
J Virol ; 85(12): 5880-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21471231

RESUMO

During acute human immunodeficiency virus (HIV) infection, there is a massive depletion of CD4(+) T cells in the gut mucosa that can be reversed to various degrees with antiretroviral therapy. Th17 cells have been implicated in mucosal immunity to extracellular bacteria, and preservation of this subset may support gut mucosal immune recovery. However, this possibility has not yet been evaluated in HIV-1-infected long-term nonprogressors (LTNPs), who maintain high CD4(+) T cell counts and suppress viral replication in the absence of antiretroviral therapy. In this study, we evaluated the immunophenotype and function of CD4(+) T cells in peripheral blood and gut mucosa of HIV-uninfected controls, LTNPs, and HIV-1-infected individuals treated with prolonged antiretroviral therapy (ART) (VL [viral load]<50). We found that LTNPs have intact CD4(+) T cell populations, including Th17 and cycling subsets, in the gut mucosa and a preserved T cell population expressing gut homing molecules in the peripheral blood. In addition, we observed no evidence of higher monocyte activation in LTNPs than in HIV-infected (HIV(-)) controls. These data suggest that, similar to nonpathogenic simian immunodeficiency virus (SIV) infection, LTNPs preserve the balance of CD4(+) T cell populations in blood and gut mucosa, which may contribute to the lack of disease progression observed in these patients.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Sobreviventes de Longo Prazo ao HIV , HIV-1/imunologia , Mucosa Intestinal/imunologia , Antígeno Ki-67/metabolismo , Células Th17/imunologia , Adulto , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Imunidade nas Mucosas/imunologia , Imunofenotipagem , Mucosa Intestinal/patologia , Mucosa Intestinal/virologia , Antígeno Ki-67/genética , Pessoa de Meia-Idade
6.
Blood ; 116(19): 3818-27, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-20660788

RESUMO

Immune reconstitution inflammatory syndrome (IRIS) is a considerable problem in the treatment of HIV-infected patients. To identify immunologic correlates of IRIS, we characterized T-cell phenotypic markers and serum cytokine levels in HIV patients with a range of different AIDS-defining illnesses, before and at regular time points after initiation of antiretroviral therapy. Patients developing IRIS episodes displayed higher frequencies of effector memory, PD-1(+), HLA-DR(+), and Ki67(+) CD4(+) T cells than patients without IRIS. Moreover, PD-1(+) CD4(+) T cells in IRIS patients expressed increased levels of LAG-3, CTLA-4, and ICOS and had a Th1/Th17 skewed cytokine profile upon polyclonal stimulation. Elevated PD-1 and Ki67 expression was also seen in regulatory T cells of IRIS patients. Furthermore, IRIS patients displayed higher serum interferon-γ, compared with non-IRIS patients, near the time of their IRIS events and higher serum interleukin-7 levels, suggesting that the T-cell populations are also exposed to augmented homeostatic signals. In conclusion, our findings indicate that IRIS appears to be a predominantly CD4-mediated phenomenon with reconstituting effector and regulatory T cells showing evidence of increased activation from antigenic exposure. These studies are registered online at http://clinicaltrials.gov as NCT00557570 and NCT00286767.


Assuntos
Fármacos Anti-HIV/efeitos adversos , Linfócitos T CD4-Positivos/imunologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/imunologia , Síndrome Inflamatória da Reconstituição Imune/etiologia , Síndrome Inflamatória da Reconstituição Imune/imunologia , Antígenos CD/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Estudos de Casos e Controles , Citocinas/sangue , HIV-1 , Humanos , Memória Imunológica , Ativação Linfocitária , Receptor de Morte Celular Programada 1 , Estudos Retrospectivos , Subpopulações de Linfócitos T/imunologia
7.
AIDS ; 24(10): 1509-17, 2010 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-20505494

RESUMO

OBJECTIVE: Cardiovascular disease (CVD) contributes significantly to HIV-related morbidity and mortality. Chronic immune activation and inflammation are thought to augment the progression of atherosclerotic disease. In this retrospective, case-control study of HIV-infected individuals, we investigated the association of traditional cardiac risk factors, HIV-related disease, and inflammation with CVD events. METHODS: HIV-infected individuals who experienced an incident CVD event while enrolled in National Institutes of Health clinical protocols from 1995 to 2009 were matched 2: 1 to HIV-infected individuals without known CVD. Markers of inflammation and cell activation were measured in serum or plasma using ELISA-based assays and peripheral mononuclear cells by four-color flow cytometry. RESULTS: Fifty-two patients experienced an incident CVD event. Events were related to smoking, dyslipidemia, hyperglycemia, and family history as well as elevated D-dimer, soluble vascular cell adhesion molecule-1, tissue inhibitor of metalloproteinase-1, and soluble tissue factor, but not high-sensitivity C-reactive protein. No significant differences in antiviral therapy, CD4 T-cell count, or CD38 and human leukocyte antigen-DR expression were identified between patients and controls. In multivariable analysis, smoking, family history, D-dimer, and glucose were independently related to CVD risk. CONCLUSION: In this cohort, CVD risk was related to traditional CVD risk factors and markers of thrombosis and endothelial damage, but not to high-sensitivity C-reactive protein or markers of T-cell activation such as CD38/human leukocyte antigen-DR coexpression. D-dimer may help identify HIV-infected patients at elevated CVD risk.


Assuntos
Aterosclerose/imunologia , Produtos de Degradação da Fibrina e do Fibrinogênio/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Molécula 1 de Adesão de Célula Vascular/imunologia , Aterosclerose/etiologia , Contagem de Linfócito CD4 , Estudos de Casos e Controles , Doença Crônica , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
8.
Diabetologia ; 50(9): 1969-1976, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17604976

RESUMO

AIMS/HYPOTHESIS: Diabetes mellitus is associated with extensive vascular pathology, yet little is known about its long-term effects on liver sinusoidal endothelial cells (LSECs). Potential diabetic changes in LSECs are important because of the role played by fenestrations in the LSECs in hepatic disposition of lipoproteins. MATERIALS AND METHODS: Surgical liver biopsies for electron microscopy and immunohistochemistry were obtained from baboons with long-standing streptozotocin-induced, insulin-treated diabetes mellitus and compared with those from age-matched control animals. RESULTS: There was an increase in the thickness of LSECs (170 +/- 17 vs 123 +/- 10 nm, p < 0.01). Fenestrations in LSECs, as determined by overall porosity, were markedly reduced (1.4 +/- 0.1% vs 2.6 +/- 0.2%, p < 0.01). Increased numbers of stellate cells were seen on electron microscopy, and this finding was corroborated by increased smooth muscle actin expression. Diabetes mellitus was also associated with increased endothelial production of von Willebrand factor and caveolin-1. CONCLUSIONS/INTERPRETATION: Diabetes mellitus in the non-human primate is associated with marked changes in LSECs, including a reduction in fenestrations. Such changes provide an additional and novel mechanism for impaired hepatic lipoprotein clearance and post-prandial hyperlipidaemia in diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 1/patologia , Células Endoteliais/patologia , Fígado/patologia , Animais , Biópsia , Glicemia/análise , Proteínas Sanguíneas/análise , Peso Corporal , Modelos Animais de Doenças , Células Endoteliais/ultraestrutura , Hemoglobinas Glicadas/análise , Lipídeos/sangue , Fígado/ultraestrutura , Microscopia Eletrônica de Varredura , Papio
9.
Proc Natl Acad Sci U S A ; 103(6): 1768-73, 2006 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-16446459

RESUMO

Age-related accumulation of cellular damage and death has been linked to oxidative stress. Calorie restriction (CR) is the most robust, nongenetic intervention that increases lifespan and reduces the rate of aging in a variety of species. Mechanisms responsible for the antiaging effects of CR remain uncertain, but reduction of oxidative stress within mitochondria remains a major focus of research. CR is hypothesized to decrease mitochondrial electron flow and proton leaks to attenuate damage caused by reactive oxygen species. We have focused our research on a related, but different, antiaging mechanism of CR. Specifically, using both in vivo and in vitro analyses, we report that CR reduces oxidative stress at the same time that it stimulates the proliferation of mitochondria through a peroxisome proliferation-activated receptor coactivator 1 alpha signaling pathway. Moreover, mitochondria under CR conditions show less oxygen consumption, reduce membrane potential, and generate less reactive oxygen species than controls, but remarkably they are able to maintain their critical ATP production. In effect, CR can induce a peroxisome proliferation-activated receptor coactivator 1 alpha-dependent increase in mitochondria capable of efficient and balanced bioenergetics to reduce oxidative stress and attenuate age-dependent endogenous oxidative damage.


Assuntos
Restrição Calórica , Metabolismo Energético , Mitocôndrias/metabolismo , Linhagem Celular , Humanos , Microscopia Eletrônica , Mitocôndrias/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo
10.
Ground Water ; 39(5): 786-94, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11554258

RESUMO

Secondary minerals occurring at the faces of fractures, the only reliable visual evidence of the presence of hydraulically conductive fractures in clayey unlithified aquitards, have been characterized for two uncontaminated field sites, Dalmeny, Saskatchewan, and Laidlaw, Ontario. Preliminary identification of secondary minerals and their variations with depth was made using a Munsell Color Chart. Subsequent microscopic analyses (petrography, electron microprobe analysis, scanning electron microscopy, and X-ray diffraction) were used to identify iron-oxide mineralogy. Iron oxides were identified as goethite, ferrihydrite, and hematite at Dalmeny, where they occur to depths of 10 to 15 m, and goethite and ferrihydrite at Laidlaw, observed to depths of 7 m. In both cases, the identification of ferrihydrite was tentative due to the problems of small sample size and peak overlap in X-ray diffraction. The iron oxides do not form coatings on the surfaces of the fractures as had been previously thought; rather they form cements linking the matrix grains. Thus there is potential for decreased permeability and increased surface reactivity parallel to and inward from the fracture faces. The pattern of iron-oxide distribution suggests that the youngest deposits, and those with the greatest surface reactivity and potential for contaminant retardation, are found at greatest depths in the fractures. Manganese oxides form in isolated clusters in larger pores and indentations, although the exact manganese minerals could not be firmly identified.


Assuntos
Compostos Férricos/química , Compostos de Manganês/química , Óxidos/química , Abastecimento de Água , Silicatos de Alumínio , Argila , Compostos Férricos/análise , Compostos de Manganês/análise , Microscopia Eletrônica de Varredura , Óxidos/análise , Permeabilidade , Pressão , Solo , Difração de Raios X
11.
J Cataract Refract Surg ; 23(5): 781-3, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9278802

RESUMO

PURPOSE: To determine whether a patient's suitability for phacoemulsification under topical anesthesia can be predicted preoperatively by their performance during tonometry and A-scan. SETTING: Whipps Cross Hospital Ophthalmology Department, London, England. METHODS: Fifty consecutive patients who were considered suitable for phacoemulsification were selected for the study. Using a scoring system we devised, observers assessed the patients for the ease with which intraocular pressure and axial length were measured. These scores were compared with an assessment of how well they tolerated phacoemulsification under topical anesthesia. Correlation between the scores was measured with Spearman's rank correlation coefficient, Kendall's rank correlation coefficient, and the Goodman-Kruskal gamma statistic. RESULTS: Phacoemulsification and posterior chamber intraocular lens implantation were completed in all patients. Statistical analysis showed that tonometry and A-scan scores correlated highly with surgery scores. Age was also a significant variable in predicting the surgery score. A significant discrepancy between tonometry and A-scan and surgery scores was found in only one patient, and it was noted that he was one of the youngest patients in the study. CONCLUSION: How well a patient performs during tonometry and A-scan was a good predictor of how well he or she tolerated having phacoemulsification under topical anesthesia. The decision about type of anesthesia should, however, also involve other factors, including communication, cooperation, and the age of the patient.


Assuntos
Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Seleção de Pacientes , Facoemulsificação/métodos , Administração Tópica , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pressão Intraocular , Lentes Intraoculares , Masculino , Pessoa de Meia-Idade , Soluções Oftálmicas , Cooperação do Paciente , Estudos Prospectivos
15.
Can J Neurol Sci ; 2(1): 31-5, 1975 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1148953

RESUMO

Thirty-nine patients with a variety of diseases, including essential tremor, Parkinson's Disease, olivopontocerebellar degeneration, ataxia telangiectasia, and cervical cord injury with action tremor, were evaluated for the effect of one ounce of absolute alcohol ingestion. Tremor significantly subsided in 61.9% of E.T.; 46.6% of P.D.; one patient with A.T.; and one patient with C6 lesion. The tremor became worse in one patient with O.P.C.D. Twenty of these patients were treated with propranolol, an average dose of 92 mgm. per day, and re-evaluated three to six months later. All those who improved on alcohol improved on propranolol and the one whose tremor accentuated with alcohol had a similar response to propranolol. It is concluded that the tremorilytic effect of alcohol is neither specific for, nor limited to, essential tremor and is of no value in differentiating various neurological disorders which manifest as action tremor. It is recommended that one ounce of absolute alcohol by mouth be used as an office procedure to predict the response of patients' tremor to propranolol.


Assuntos
Etanol/uso terapêutico , Propranolol/uso terapêutico , Tremor/tratamento farmacológico , Adulto , Ataxia Telangiectasia/tratamento farmacológico , Doenças Cerebelares/tratamento farmacológico , Avaliação de Medicamentos , Etanol/sangue , Feminino , Humanos , Masculino , Doença de Parkinson/tratamento farmacológico , Traumatismos da Medula Espinal/tratamento farmacológico
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