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1.
Mon Not R Astron Soc ; 490(2): 2958-2975, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31708598

RESUMO

The cosmic microwave background (CMB) B-mode signal is potentially weaker than the diffuse Galactic foregrounds over most of the sky at any frequency. A common method of separating the CMB from these foregrounds is via pixel-based parametric-model fitting. There are not currently enough all-sky maps to fit anything more than the most simple models of the sky. By simulating the emission in seven representative pixels, we demonstrate that the inclusion of a 5 GHz data point allows for more complex models of low-frequency foregrounds to be fitted than at present. It is shown that the inclusion of the C-BASS data will significantly reduce the uncertainties in a number of key parameters in the modelling of both the galactic foregrounds and the CMB. The extra data allow estimates of the synchrotron spectral index to be constrained much more strongly than is presently possible, with corresponding improvements in the accuracy of the recovery of the CMB amplitude. However, we show that to place good limits on models of the synchrotron spectral curvature will require additional low-frequency data.

2.
Mucosal Immunol ; 9(6): 1429-1441, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27007677

RESUMO

The local immune response occurring during Staphylococcus aureus nasal colonization remains ill-defined. Studies have highlighted the importance of T-cell immunity in controlling S. aureus colonization of the nasal mucosa. We extend these observations, identifying a critical role for interleukin (IL)-22 in this process. IL-22 is basally expressed within the nasal mucosa and is induced upon S. aureus colonization. IL-22 is produced by CD4+ and CD8+ T lymphocytes at this site, with innate-like lymphocytes also contributing. IL-22-/- mice demonstrate significantly elevated levels of S. aureus nasal colonization as compared with wild-type (WT) mice. This was associated with reduced expression of antimicrobial peptides (AMPs) in the nose. Furthermore, expression of staphylococcal ligands loricrin and cytokeratin 10 was higher in the noses of IL-22-/- as compared with WT mice. IL-17 has been shown to regulate S. aureus nasal colonization by controlling local neutrophil responses; however, IL-17 expression and neutrophil responses were comparable in the noses of IL-22-/- and WT mice during S. aureus colonization. We conclude that IL-22 has an important role in controlling S. aureus nasal colonization through distinct mechanisms, with IL-22 mediating its effect exclusively by inducing AMP expression and controlling availability of staphylococcal ligands.


Assuntos
Peptídeos Catiônicos Antimicrobianos/genética , Diferenciação Celular/genética , Interleucinas/genética , Queratinócitos/citologia , Mucosa Nasal/metabolismo , Mucosa Nasal/microbiologia , Infecções Estafilocócicas/genética , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia , Monofosfato de Adenosina , Animais , Modelos Animais de Doenças , Expressão Gênica , Interleucinas/metabolismo , Camundongos , Camundongos Knockout , Infecções Estafilocócicas/imunologia , Staphylococcus aureus/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Interleucina 22
3.
Clin Exp Immunol ; 172(2): 158-68, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23574313

RESUMO

Transplantation is a successful treatment for end-stage organ failure. Despite improvements in short-term outcome, long-term survival remains suboptimal because of the morbidity and mortality associated with long-term use of immunosuppression. There is, therefore, a pressing need to devise protocols that induce tolerance in order to minimize or completely withdraw immunosuppression in transplant recipients. In this review we will discuss how regulatory T cells (T(regs)) came to be recognized as an attractive way to promote transplantation tolerance. We will summarize the preclinical data, supporting the importance of these cells in the induction and maintenance of immune tolerance and that provide the rationale for the isolation and expansion of these cells for cellular therapy. We will also describe the data from the first clinical trials, using T(regs) to inhibit graft-versus-host disease (GVHD) after haematopoietic stem cell transplantation and will address both the challenges and opportunities in human T(reg) cell therapy.


Assuntos
Transferência Adotiva , Terapia Baseada em Transplante de Células e Tecidos , Transplante de Células-Tronco Hematopoéticas , Linfócitos T Reguladores/transplante , Doença Enxerto-Hospedeiro/imunologia , Doença Enxerto-Hospedeiro/terapia , Humanos , Linfócitos T Reguladores/imunologia , Tolerância ao Transplante
4.
Clin Exp Immunol ; 172(2): 169-77, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23574314

RESUMO

Cell-based therapies using natural or genetically modified regulatory T cells (T(regs)) have shown significant promise as immune-based therapies. One of the main difficulties facing the further advancement of these therapies is that the fate and localization of adoptively transferred T(regs) is largely unknown. The ability to dissect the migratory pathway of these cells in a non-invasive manner is of vital importance for the further development of in-vivo cell-based immunotherapies, as this technology allows the fate of the therapeutically administered cell to be imaged in real time. In this review we will provide an overview of the current clinical imaging techniques used to track T cells and T(regs) in vivo, including magnetic resonance imaging (MRI) and positron emission tomography (PET)/single photon emission computed tomography (SPECT). In addition, we will discuss how the finding of these studies can be used, in the context of transplantation, to define the most appropriate T(reg) subset required for cellular therapy.


Assuntos
Transferência Adotiva , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Linfócitos T Reguladores/fisiologia , Linfócitos T Reguladores/transplante , Tomografia Computadorizada de Emissão de Fóton Único , Animais , Linhagem Celular , Diagnóstico por Imagem , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Transplante
5.
Indoor Air ; 14(3): 169-73, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15104783

RESUMO

UNLABELLED: A prospective telephone-administered questionnaire study in new home occupants compared general and respiratory health at occupancy and 1 year later in two groups. The test group or cases, was 52 R-2000(TM) homes (128 occupants) built to preset and certified criteria for energy efficient ventilation and construction practices. The control group were 53 new homes (149 occupants) built in the same year in the same geographic area and price range. Analyzed by household, case occupants' summative symptom scores improved significantly over the year of occupancy (Wilcoxon rank sum test, P < 0.006). Analysis of variance of individuals' total symptom scores showed a significant effect of the type of house (P < 0.0001), with lower change of scores in case buildings, but not of age or sex. In comparison with control homes, occupants of case homes reported more improvement in throat irritation (P < 0.004), cough (P < 0.002), fatigue (P < 0.009) and irritability (P < 0.002) with the main change in symptom category being from 'sometimes' to 'never'. Further extension of this pilot study is required to determine if these perceived health benefits are reproducible and/or relate to objective indoor air quality measures. PRACTICAL IMPLICATIONS: New occupants of energy efficient homes with heat recovery ventilators report improvement over 1 year in the symptoms of throat irritation, cough, fatigue, and irritability in comparison with control new home occupants. If this pilot study is reproducible and shown to relate to indoor air quality, prospective new home buyers may be interested in obtaining this health information prior to decision making.


Assuntos
Nível de Saúde , Habitação , Ventilação , Adolescente , Adulto , Afeto , Idoso , Estudos de Casos e Controles , Criança , Pré-Escolar , Tosse , Fadiga , Feminino , Inquéritos Epidemiológicos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Faringe/patologia , Fatores de Tempo
6.
Eye (Lond) ; 17(1): 41-6, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12579169

RESUMO

PURPOSE: To evaluate the safety and efficacy of the timolol/dorzolamide fixed combination vs latanoprost 0.005% in exfoliation glaucoma patients. METHODS: We randomized in an observer-masked fashion 65 newly diagnosed exfoliation glaucoma patients to either the timolol/dorzolamide twice daily or latanoprost daily treatment for 2 months and then crossed these over to the other treatment. RESULTS: A total of fifty-four patients completed the study. After 2 months of chronic dosing, the morning intraocular pressure (IOP) (10:00) was reduced from a baseline of 31.2+/-6.5 mmHg to 18.1+/-3.0 with the fixed combination and to 18.9+/-4.1 mmHg with latanoprost (P = 0.21). Six patients were discontinued early from both treatment periods owing to inadequate IOP control and two others were discontinued from latanoprost treatment only. The fixed combination showed a significantly greater incidence of taste perversion (P < 0.001) and stinging upon instillation (P = 0.036), while latanoprost showed a trend for increased conjunctival injection (P = 0.056). However, five patients demonstrated either bradycardia or asthmatic symptoms with initiation of the fixed combination therapy. One patient on latanoprost complained of dizziness. Patient preference was generally given to latanoprost (63 vs 20.3%) mainly because of its once daily dosing (P < 0001). CONCLUSIONS: This study suggests that both latanoprost and the timolol/dorzolamide fixed combination are efficacious in the treatment of newly diagnosed exfoliation glaucoma.


Assuntos
Anti-Hipertensivos/uso terapêutico , Glaucoma de Ângulo Aberto/tratamento farmacológico , Prostaglandinas F Sintéticas/uso terapêutico , Sulfonamidas/uso terapêutico , Tiofenos/uso terapêutico , Timolol/uso terapêutico , Antagonistas Adrenérgicos beta/efeitos adversos , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Anti-Hipertensivos/efeitos adversos , Inibidores da Anidrase Carbônica/efeitos adversos , Inibidores da Anidrase Carbônica/uso terapêutico , Combinação de Medicamentos , Feminino , Glaucoma de Ângulo Aberto/fisiopatologia , Humanos , Pressão Intraocular/efeitos dos fármacos , Latanoprosta , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Prostaglandinas F Sintéticas/efeitos adversos , Método Simples-Cego , Sulfonamidas/efeitos adversos , Tiofenos/efeitos adversos , Timolol/efeitos adversos
7.
Am J Epidemiol ; 153(5): 444-52, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11226976

RESUMO

To clarify the health effects of ozone exposure in young children, the authors studied the association between air pollution and hospital admissions for acute respiratory problems in children less than 2 years of age during the 15-year period from 1980 to 1994 in Toronto, Canada. The daily time series of admissions was adjusted for the influences of day of the week, season, and weather. A 35% (95% confidence interval: 19%, 52%) increase in the daily hospitalization rate for respiratory problems was associated with a 5-day moving average of the daily 1-hour maximum ozone concentration of 45 parts per billion, the May-August average value. The ozone effect persisted after adjustment for other ambient air pollutants or weather variables. Ozone was not associated with hospital admissions during the September-April period. Ambient ozone levels in the summertime should be considered a risk factor for respiratory problems in children less than 2 years of age.


Assuntos
Poluição do Ar/efeitos adversos , Criança Hospitalizada/estatística & dados numéricos , Hospitalização/estatística & dados numéricos , Ozônio/efeitos adversos , Doenças Respiratórias/epidemiologia , Doença Aguda , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Ontário/epidemiologia , Doenças Respiratórias/etiologia , Fatores de Risco , Estações do Ano , Saúde da População Urbana/estatística & dados numéricos
8.
Infect Control Hosp Epidemiol ; 22(11): 697-700, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11842990

RESUMO

OBJECTIVE: To describe an outbreak of hepatitis C in a clinical research study. DESIGN: Observational study. SETTING: Tertiary-care hospital. PATIENTS: Healthcare workers who volunteered to be subjects in a study of the metabolic effects of inhaled and oral corticosteroids who were unwittingly exposed to hepatitis C virus (HCV). METHODS: Epidemiological investigation and serological analyses. RESULTS: One chronic carrier of HCV was identified. Four fellow workers volunteering in the studies became infected with HCV, with 96% homology among strains. There was no evidence of spread from infected healthcare workers to patients on whom they had performed arterial punctures (2 of 214 positive, unrelated to each other and to the outbreak strain). CONCLUSION: Infection control standards in clinical research must be maintained vigorously to prevent transmission of blood-borne pathogens such as HCV.


Assuntos
Corticosteroides/efeitos adversos , Surtos de Doenças , Hepatite C/epidemiologia , Hepatite C/transmissão , Recursos Humanos em Hospital/estatística & dados numéricos , Corticosteroides/administração & dosagem , Corticosteroides/farmacologia , Adulto , Feminino , Hepacivirus/imunologia , Humanos , Masculino , Pessoa de Meia-Idade , Observação , Ontário/epidemiologia , Inquéritos e Questionários
9.
Am J Ophthalmol ; 130(6): 712-6, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11124288

RESUMO

PURPOSE: We evaluated the anterior segment surface reaction findings between timolol hemihydrate and timolol maleate. The only known difference between these preparations is the maleate salt. METHODS: After a baseline examination, we randomized 28 healthy subjects (26 completed) to timolol hemihydrate or timolol maleate given in both eyes twice daily, in a double masked fashion, for 1 week. Subjects then were evaluated at the morning trough (hour 0 examination), dosed, and re-evaluated in 1 hour (hour 1 examination). Subjects were left untreated for 1 week and then switched to the opposite medication for the second study period. RESULTS: Corneal staining (graded 0 to 4) for timolol maleate was worse between baseline (0.9) and hour 0 (1.4; P =.009) and baseline and hour 1 (1.4; P =.011). Also, mean punctate corneal staining for timolol maleate was increased from baseline (22.6) to hour 0 (31.7; P =.033) and showed borderline significance to hour 1 (33.4; P =.058), and for timolol hemihydrate there was a borderline significant elevation from baseline (24.2) to hour 1 (29.8; P =.060). When treatment groups were compared, there was a greater change in corneal staining with timolol maleate than timolol hemihydrate from baseline to hour 0 (P =.020) and greater staining with timolol maleate than timolol hemihydrate at hour 0 (P =.032). Nasal conjunctiva showed increased mean staining with timolol maleate from baseline (23.6, P =.035) to hour 0 (29.5, P =.035) and to hour 1 (31.9 P =.038) but not with timolol hemihydrate. There were increased symptoms of ocular dryness from baseline to hour 0 with timolol maleate (P =.012) but not with timolol hemihydrate. CONCLUSIONS: The study suggests that timolol maleate potentially may have more of an irritant effect than timolol hemihydrate on the corneal and nasal conjunctival epithelium.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Túnica Conjuntiva/efeitos dos fármacos , Córnea/efeitos dos fármacos , Timolol/farmacologia , Adulto , Túnica Conjuntiva/patologia , Córnea/patologia , Método Duplo-Cego , Avaliação de Medicamentos , Epitélio/efeitos dos fármacos , Epitélio/patologia , Feminino , Humanos , Irritantes/farmacologia , Masculino , Soluções Oftálmicas , Segurança
10.
Am J Ophthalmol ; 130(3): 274-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11020404

RESUMO

PURPOSE: To evaluate long-term risk factors for progression or stability in patients with primary open-angle glaucoma. METHOD: We retrospectively included consecutively reviewed patients who had primary open-angle glaucoma for at least 5 years in this multicenter trial. Historical and clinical factors in these patients were evaluated for their association with stability or progression of the glaucoma. RESULTS: We included 218 patients in this study; of these, 34 progressed over an average length of follow-up of 45.5 +/- 30.0 months, and 184 were stable over an average of 72.8 +/- 18.3 months. The mean intraocular pressure over the follow-up period for the progressed group was 19.5 +/- 3.8 mm Hg and for the stable group 17. 2 +/- 3.1 mm Hg (P =.001). The average standard deviation of individual intraocular pressures was greater in the progressed group (5.1 mm Hg) than the stable group (3.9 mm Hg, P =.012). Baseline characteristics indicating a greater potential to progress were a larger cup-to-disk ratio (P <.001), a greater number of medications (P =.02), older age (P.007), and worse visual acuity (P =.003). However, no difference was observed in pressure levels that prevented progression in these subpopulations compared with the total sample size. CONCLUSIONS: This study suggests that lowering the intraocular pressure is important in the treatment of primary open-angle glaucoma to help prevent long-term progression. Lowering the pressure, however, is not uniformly effective in preventing progression. Additionally, risk factors for progression do not further help identify pressure levels that prevent worsening of glaucoma.


Assuntos
Glaucoma de Ângulo Aberto/fisiopatologia , Idoso , Progressão da Doença , Feminino , Seguimentos , Humanos , Pressão Intraocular/fisiologia , Masculino , Nervo Óptico/fisiopatologia , Estudos Retrospectivos , Fatores de Risco , Acuidade Visual/fisiologia , Campos Visuais/fisiologia
11.
J Ocul Pharmacol Ther ; 16(6): 557-64, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11132902

RESUMO

The purpose of this study was to evaluate the success rate ofmonotherapy with latanoprost 0.005% once daily versus brimonidine 0.2% twice daily in patients with open-angle glaucoma or ocular hypertension. Patients who were prescribed latanoprost or brimonidine as monotherapy were included in this study, and their consecutive charts were retrospectively reviewed. The primary efficacy variable was success of therapy, defined as a reduction in intraocular pressure > or =3 mm Hg without an adverse event leading to discontinuation over a potential of six months of therapy. We included 157 patients in this study. In the latanoprost group, 64 of 92 (70%) were considered successes; 26 of 65 (40%) were successful with brimonidine (P < 0.001). Nine failed brimonidine therapy, and one latanoprost, because of an adverse event, and the rest failed because of inadequate intraocular pressure response. The change from baseline in intraocular pressure was significantly greater with latanoprost (mean +/- S.D., 21.6 +/- 5.1 to 17.1 +/- 3.3 mm Hg) than brimonidine (23.7 +/- 5.6 to 21.9 +/- 5.7 mm Hg) (P = 0.001). Overall, 52 (80%) brimonidine- and 41 (45%) latanoprost-treated patients required additional visit(s) to adjust therapy to further lower intraocular pressure or to assess an adverse event (P < 0.001). In conclusion, latanoprost more likely provides a successful response to therapy than brimonidine when used as monotherapy in primary open-angle glaucoma or ocular hypertensive patients.


Assuntos
Agonistas alfa-Adrenérgicos/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Glaucoma de Ângulo Aberto/tratamento farmacológico , Pressão Intraocular/efeitos dos fármacos , Prostaglandinas F Sintéticas/uso terapêutico , Quinoxalinas/uso terapêutico , Agonistas alfa-Adrenérgicos/administração & dosagem , Adulto , Anti-Hipertensivos/administração & dosagem , Tartarato de Brimonidina , Feminino , Humanos , Latanoprosta , Masculino , Hipertensão Ocular/tratamento farmacológico , Soluções Oftálmicas , Prostaglandinas F Sintéticas/administração & dosagem , Quinoxalinas/administração & dosagem , Estudos Retrospectivos , Resultado do Tratamento
12.
Inhal Toxicol ; 11(8): 657-74, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10477441

RESUMO

We examined ozone-induced upper and lower airway inflammatory responses and the concentrations of hydroxylated salicylate metabolites using nasal lavage fluid and induced sputum, in order to identify noninvasive and sensitive biomarkers for ozone exposure and effects. A time course for plasma concentration of 2, 3-dihydroxybenzoic acid (2,3-DHBA, a salicylate metabolite and an indicator for hydroxyl radical) in response to 0.12 ppm ozone was also studied. Healthy, young, nonsmoking volunteers were given acetylsalicylic acid (ASA, 975 mg) or placebo orally. Subjects were exposed to ozone (0.12 or 0.4 ppm) or filtered air in an environmental chamber for 2 h, while performing intermittent exercise. Blood was collected hourly over a 4-h period. After exposure, nasal lavage fluid was collected, and sputum was induced using hypertonic saline. Results show that in sputum the percentage of neutrophils was significantly higher after the subjects were exposed to 0.4 ppm ozone (p<.05) than after they were exposed to filtered air or 0.12 ppm ozone. The absolute number and the percentage of macrophages were significantly lower at 0.4 ppm ozone than for filtered air control or 0.12 ppm ozone. The percentage of lymphocytes in sputum was also significantly lower at 0.4 ppm ozone than for filtered air control or 0.12 ppm ozone. The sputum cellular responses to ozone were not significantly altered by ASA treatment. In nasal lavage, cell counts and differentials did not change significantly after exposure to ozone in comparison to filtered air control. The cellular data indicate an acute inflammation developed during ozone exposure in the lower respiratory tract. The concentrations of total protein and interleukin-8 and the activity of N-acetyl-beta-D-glucosaminidase (a lysosomal enzyme) in nasal lavage and sputum did not change significantly following exposure to ozone in comparison to filtered air control. Plasma 2,3-DHBA concentration increased significantly following exposure to 0.12 ppm ozone in an exposure-dependent temporal pattern. Salicylate metabolites in nasal lavage fluid and sputum did not increase significantly following exposure to ozone. There was a marked variation of 2,3-DHBA concentrations in airway fluids. Data suggest that plasma 2,3-DHBA is a sensitive marker indicating acute ozone exposure, even at an ozone concentration that causes minimal observable airway effects in healthy subjects.


Assuntos
Exposição por Inalação/efeitos adversos , Mucosa Nasal/metabolismo , Oxidantes Fotoquímicos/toxicidade , Ozônio/toxicidade , Escarro/metabolismo , Adolescente , Adulto , Biomarcadores , Diferenciação Celular/efeitos dos fármacos , Humanos , Hidroxilação , Interleucina-8/metabolismo , Masculino , Mucosa Nasal/citologia , Ozônio/sangue , Testes de Função Respiratória , Salicilatos/metabolismo , Escarro/citologia , Irrigação Terapêutica
13.
Can J Public Health ; 90(4): 244-9, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10489721

RESUMO

This subanalysis of the Canadian Human Activity Pattern Survey examines environmental tobacco smoke (ETS) exposure in non-smoking respondents relative to age, sex, socioeconomic status and prevalence of asthma. 2,381 respondents (response rate 64.5%) from Toronto, Vancouver, Edmonton and Saint John completed a 24-hour recall time-activity diary. For each activity and location, respondents were asked, "was there any smoking during the activity?" Among non-smoking adults, youth, children and asthmatics, the rates of ETS exposure were 32%, 34%, 30% and 42% respectively. Regarding the location of exposure, adults reported ETS exposure in various locations (work, bars and restaurants), including home. Children experienced the most exposure at home, primarily between 4 p.m. and midnight. Adults reported ETS mainly in the living room (16%) and vehicles (13%); for children, the living room (22%) and the bedroom (13%) were the most common locations. Determining characteristic time and location patterns for ETS exposure underpins educational strategies to help non-smokers avoid ETS exposure.


Assuntos
Asma/epidemiologia , Asma/etiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Estudos de Tempo e Movimento , Poluição por Fumaça de Tabaco/efeitos adversos , Poluição por Fumaça de Tabaco/estatística & dados numéricos , Adolescente , Adulto , Distribuição por Idade , Canadá/epidemiologia , Criança , Pré-Escolar , Interpretação Estatística de Dados , Monitoramento Epidemiológico , Feminino , Humanos , Masculino , Vigilância da População , Prevalência , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo
14.
Am J Respir Crit Care Med ; 156(5): 1405-12, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9372653

RESUMO

Ozone is known to yield hydroxyl radical, which may contribute to ozone-mediated lung injury. In the presence of hydroxyl radical, salicylate is hydroxylated to form 2,3-dihydroxybenzoic acid (2,3-DHBA). There is no evidence of enzymatic formation of 2,3-DHBA. We hypothesized that salicylate hydroxylation might be used as a biomarker indicating human exposure to ozone. Healthy, nonsmoking volunteers, 18 to 34 yr of age, were given acetylsalicylic acid (975 mg) or placebo orally 0.5 h before an exposure. Subjects were exposed to ozone (0.12 or 0.4 ppm) or filtered air in an environmental chamber for 2 h, while performing intermittent exercise. Results indicate significant decrements in FVC, FEV1.0, forced expiratory flows at 50% and 75% of FVC, and peak expiratory flow rate, and an increase in airway resistance, after exposure to 0.4 ppm ozone in comparison with air control (p < 0.05). Exposure to 0.4 ppm ozone also resulted in increased symptom numbers and severity (p < 0.05). When subjects were exposed to 0.12 ppm ozone, changes of pulmonary function and symptoms reported were minimal. Plasma concentration of 2,3-DHBA was significantly increased after exposure to 0.12 and 0.4 ppm ozone in comparison with air control (p < 0.05). There was a significant correlation between ozone-induced changes of pulmonary function and normalized salicylate hydroxylation (p < 0.05). The results indicate that exposure to ozone can initiate in vivo production of hydroxyl radical, a potent reactive agent. Salicylate hydroxylation may then serve as a sensitive dosimetric biomarker for ozone exposure, even at subclinical ozone exposure levels.


Assuntos
Aspirina/farmacocinética , Biomarcadores/sangue , Exposição por Inalação , Ozônio/efeitos adversos , Adolescente , Adulto , Resistência das Vias Respiratórias/efeitos dos fármacos , Aspirina/sangue , Testes de Provocação Brônquica , Broncoconstritores , Fluxo Expiratório Forçado/efeitos dos fármacos , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Hidroxibenzoatos/sangue , Hidroxilação , Cloreto de Metacolina , Capacidade de Difusão Pulmonar/efeitos dos fármacos , Capacidade Vital/efeitos dos fármacos
15.
Exp Eye Res ; 65(4): 555-68, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9464188

RESUMO

We have investigated the relationships of the cellular constituents of the retinal vasculature--astrocytes, microglia and pericytes--to the differentiating endothelium in human fetal retina. The vascular endothelium was stained using NADPH-diaphorase histochemistry in 12 human fetal retinae ranging in gestational age from 15-22 weeks. Specimens were double labeled using antibodies against glial fibrillary acid protein, alpha smooth muscle actin, or major histocompatibility complex class II antigens to label astrocytes, contractile cells and microglia, respectively. In addition, specimens of 12, 14, 16 and 20 weeks gestation were hybridized in situ for VEGF expression. In retinal wholemounts the vascularized area comprised four lobes that converged on the optic disc. The vascular network was more dense in the temporal lobes than in the nasal lobes, and different growth patterns were evident. Astrocytes were distributed in two layers--one associated with the optic axons and a deeper layer associated with the developing vessels. In retinae younger than 20 weeks, astrocytes in the deep layer were only loosely associated with the developing vessels and extended as far as 150 microns ahead of the most peripheral vessels. A closer register between retinal vessels and the distribution of astrocytes was evident in the nasal region of retinas older than 20 weeks. In situ hybridization demonstrated expression of VEGF mRNA in the vascular layer, superficial to the ganglion cell layer, at the margins of the vascularized zone. Differences were evident in the density of astrocyte coverage of developing vessels and in the extent of VEGF expression in different regions of the retina: the relationship of these differences to differentiation gradients in the neural retina is discussed. Intensely immunoreactive microglia were observed in the vascular layer, associated with the vascular endothelium as far as the most peripheral loops, but not beyond. Alpha smooth muscle actin-containing cells covered the proximal parts of large arteries, but not corresponding veins; they were absent from arterial side-arm branches, as well as the newly formed and small diameter vessels in the age range studies. The results suggest that microglia, contractile cells and astrocytes have distinct temporo-spatial relationships to the differentiating vascular endothelium in human retinas and that VEGF expression at the vascular front, presumably by astrocytes, is associated with the spread of the retinal vasculature, as described in other species.


Assuntos
Fatores de Crescimento Endotelial/metabolismo , Linfocinas/metabolismo , Vasos Retinianos/embriologia , Diferenciação Celular , Movimento Celular , Endotélio Vascular/citologia , Endotélio Vascular/embriologia , Humanos , Imuno-Histoquímica , Músculo Liso Vascular/citologia , Músculo Liso Vascular/embriologia , Vasos Retinianos/citologia , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
16.
Chronic Dis Can ; 17(3-4): 118-23, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9097012

RESUMO

The assessment of health risk due to environmental contaminants depends upon accurate estimates of the distribution of population exposures. Exposure assessment, in turn, requires information on the time people spend in micro-environments and their activities during periods of exposure. This paper describes preliminary results including study methodology and population sampled in a large Canadian survey of time-activity patterns. A 24-hour diary recall survey was performed in 2381 households (representing a 65% response rate) to describe in detail the timing, location and activity pattern of one household member (the adult or child with the next birthday). Four cities (Toronto, Vancouver, Edmonton and Saint John, NB) and their suburbs were sampled by random-digit dialling over a nine-month period in 1994/1995. Supplemental questionnaires inquiring about sociodemographic information, house and household characteristics and potential exposure to toxins in the air and water were also administered. In general, the results show that respondents spend the majority of their time indoors (88.6%) with smaller proportions of time outdoors (6.1%) and in vehicles (5.3%). Children under the age of 12 spend more time both indoors and outdoors and less time in transit than do adults. The data from this study will be used to define more accurately the exposure of Canadians to a variety of toxins in exposure assessment models and to improve upon the accuracy of risk assessment for a variety of acute and chronic health effects known or suspected to be related to environmental exposures.


Assuntos
Exposição Ambiental , Inquéritos Epidemiológicos , Estilo de Vida , Adolescente , Adulto , Idoso , Canadá , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade
17.
Exp Parasitol ; 81(1): 79-89, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7628570

RESUMO

Members of a serologically cross-reacting family of proteins including Ag332 and Pf11.1, megadalton proteins of schizont-infected red blood cells, and gametocytes, respectively, and Pf155-RESA, a 155-kDa protein of ring-infected red blood cells, have been reported to share amino acid repeat sequences. These repeats are rich in glutamic acid dipeptides postulated to be involved in generating serologic cross-reactivity. We report the identification and characterization of another member of this cross-reacting family, a 260-kDa glutamic acid-rich intraerythrocytic protein. Human antibodies affinity purified on the 260-kDa region of Western boots of trophozoite proteins of Plasmodium falciparum were used to screen a trophozoite-stage lambda gt11 cDNA library. A 1.8-kb clone was identified and human antibodies were affinity purified on the expressing clone. Using this affinity-purified antibody and the 1.8-kb clone, the corresponding protein, its gene, and its chromosomal location were investigated. The 260-kDa corresponding protein serologically cross-reacts with Pf155-RESA, but is the product of a different gene. The 260-kDa protein is Triton X-100 soluble and is variable in molecular weight in different isolates. Immunoprecipitation of [35S]methionine-labeled infected red blood cells indicates that the protein is synthesized throughout the intraerythrocytic cycle but is most prominent in schizonts. The protein, as has been shown previously, is not immunoprecipitated from 125I surface-labeled infected red blood cells and is thus not PfEMP1, the antigen associated with cytoadherence. Indirect fluorescent antibody studies using fixed infected red blood cells suggest that the protein is localized to the periphery of the intraerythrocytic parasite.


Assuntos
Ácido Glutâmico , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/biossíntese , Sequência de Aminoácidos , Animais , Anticorpos Antiprotozoários , Sequência de Bases , Western Blotting , Clonagem Molecular , Primers do DNA , Eritrócitos/parasitologia , Genes de Protozoários , Humanos , Dados de Sequência Molecular , Peso Molecular , Plasmodium falciparum/genética , Plasmodium falciparum/patogenicidade , Proteínas de Protozoários/análise , Proteínas de Protozoários/química , Proteínas Recombinantes/análise , Proteínas Recombinantes/biossíntese , Homologia de Sequência de Aminoácidos
18.
J Air Waste Manag Assoc ; 45(4): 223-34, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7743405

RESUMO

An ozone (O3) exposure assessment study was conducted in Toronto, Ontario, Canada during the winter and summer of 1992. A new passive O3 sampler developed by Harvard was used to measure indoor, outdoor, and personal O3 concentrations. Measurements were taken weekly and daily during the winter and summer, respectively. Indoor samples were collected at a total of 50 homes and workplaces of study participants. Outdoor O3 concentrations were measured both at home sites using the passive sampler and at 20 ambient monitoring sites with continuous monitors. Personal O3 measurements were collected from 123 participants, who also completed detailed time-activity diaries. A total of 2,274 O3 samples were collected. In addition, weekly air exchange rates of homes were measured.


Assuntos
Poluentes Ocupacionais do Ar/análise , Exposição Ambiental , Ozônio/análise , Adolescente , Adulto , Criança , Pré-Escolar , Monitoramento Ambiental , Humanos , Pessoa de Meia-Idade , Ontário
19.
J Clin Epidemiol ; 47(12): 1443-9, 1994 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7730853

RESUMO

Contrary to the issues of perioperative morbidity and survival following surgery for lung cancer, little attention has been given to quality-of-life. To address this, quality-of-life was assessed preoperatively and 1, 3, 6 and 9 months postoperatively in a cohort of 117 consecutive subjects who underwent thoracotomy with a certain or presumptive diagnosis of lung cancer. Those with cancer (n = 91) confirmed at thoracotomy were contrasted to those without (n = 26). Moderate to severe dyspnea, reported in 14% preoperatively, increased to 34% at 1 and 3 months (p < 0.005) but returned to approximately 10% at 6 and 9 months. Similarly, activities of daily living were impaired in 11% preoperatively; this disability increased to 21% at 1 month (p < 0.005), and returned to baseline at 6 and 9 months. Those with cancer compared to those without a postoperative diagnosis of cancer had similar quality-of-life preoperatively but deteriorated more in the postoperative period. This study demonstrates that important deterioration in quality-of-life occurs during the first 3 months postoperatively in those with a final diagnosis of cancer but improvement back to baseline can be expected thereafter.


Assuntos
Neoplasias Pulmonares/cirurgia , Qualidade de Vida , Toracotomia , Atividades Cotidianas , Idoso , Dispneia/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo
20.
Trustee ; 47(9): 10-3, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10136514

RESUMO

Today you are a hospital trustee. If health care reform doesn't scare you away, tomorrow you could be governing a system, a network, a physician/hospital organization, or a community hospital that belongs to one of these other entities. managed care will change your priorities, your responsibilities, and the expectations others have of you as well as the health care delivery system. To learn more about the trustee's role in a reformed health care system, the American Hospital Association and Trustee recently convened a governance symposium (see the list of participants on the opposite page). The first part of the discussion from that symposium was presented in the August issue (see "Quantum leap," page 6). The second part focuses on the issues of board accountability and compensation and realigning incentives for the future.


Assuntos
Conselho Diretor/organização & administração , Hospitais Filantrópicos , Hospitais com Fins Lucrativos/organização & administração , Hospitais Filantrópicos/economia , Hospitais Filantrópicos/organização & administração , Hospitais Filantrópicos/tendências , Relações Interprofissionais , Objetivos Organizacionais , Salários e Benefícios , Responsabilidade Social , Impostos , Estados Unidos
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