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1.
J Med Microbiol ; 69(2): 256-264, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31264957

RESUMO

Background. The Serious Outcomes Surveillance Network of the Canadian Immunization Research Network (CIRN SOS) has been performing active influenza surveillance since 2009 (ClinicalTrials.gov identifier: NCT01517191). Influenza A and B viruses are identified and characterized using real-time reverse-transcriptase polymerase chain reaction (RT-PCR), and multiplex testing has been performed on a subset of patients to identify other respiratory virus aetiologies. Since both methods can identify influenza A and B, a direct comparison was performed.Methods. Validated real-time RT-PCRs from the World Health Organization (WHO) to identify influenza A and B viruses, characterize influenza A viruses into the H1N1 or H3N2 subtypes and describe influenza B viruses belonging to the Yamagata or Victoria lineages. In a subset of patients, the Seeplex RV15 One-Step ACE Detection assay (RV15) kit was also used for the detection of other respiratory viruses.Results. In total, 1111 nasopharyngeal swabs were tested by RV15 and real-time RT-PCRs for influenza A and B identification and characterization. For influenza A, RV15 showed 98.0 % sensitivity, 100 % specificity and 99.7 % accuracy. The performance characteristics of RV15 were similar for influenza A subtypes H1N1 and H3N2. For influenza B, RV15 had 99.2 % sensitivity, 100 % specificity and 99.8 % accuracy, with similar assay performance being shown for both the Yamagata and Victoria lineages.Conclusions. Overall, the detection of circulating subtypes of influenza A and lineages of influenza B by RV15 was similar to detection by real-time RT-PCR. Multiplex testing with RV15 allows for a more comprehensive respiratory virus surveillance in hospitalized adults, without significantly compromising the reliability of influenza A or B virus detection.


Assuntos
Vírus da Influenza A/isolamento & purificação , Vírus da Influenza B/isolamento & purificação , Influenza Humana/virologia , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase Multiplex/métodos , Adulto , Canadá/epidemiologia , Feminino , Hospitalização , Humanos , Vírus da Influenza A/classificação , Vírus da Influenza A/genética , Vírus da Influenza B/classificação , Vírus da Influenza B/genética , Influenza Humana/diagnóstico , Influenza Humana/epidemiologia , Influenza Humana/terapia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
2.
Clin Infect Dis ; 69(6): 970-979, 2019 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-30508064

RESUMO

BACKGROUND: Recent studies have demonstrated the possibility of negative associations between prior influenza vaccines and subsequent influenza vaccine effectiveness (VE), depending on season and strain. We investigated this association over 4 consecutive influenza seasons (2011-2012 through 2014-2015) in Canada. METHODS: Using a matched test-negative design, laboratory-confirmed influenza cases and matched test-negative controls admitted to hospitals were enrolled. Patients were stratified into 4 groups according to influenza vaccine history (not vaccinated current and prior season [referent], vaccinated prior season only, vaccinated current season only, and vaccinated both current and prior season). Conditional logistic regression was used to estimate VE; prior vaccine impact was assessed each season for overall effect and effect stratified by age (<65 years, ≥65 years) and type/subtype (A/H1N1, A/H3N2, influenza B). RESULTS: Overall, mainly nonsignificant associations were observed. Trends of nonsignificant decreased VE among patients repeatedly vaccinated in both prior and current season relative to the current season only were observed in the A/H3N2-dominant seasons of 2012-2013 and 2014-2015. Conversely, in 2011-2012, during which B viruses circulated, and in 2013-2014, when A/H1N1 circulated, being vaccinated in both seasons tended to result in a high VE in the current season against the dominant circulating subtype. CONCLUSIONS: Prior vaccine impact on subsequent VE among Canadian inpatients was mainly nonsignificant. Even in circumstances where we observed a trend of negative impact, being repeatedly vaccinated was still more effective than not receiving the current season's vaccine. These findings favor continuation of annual influenza vaccination recommendations, particularly in older adults. CLINICAL TRIALS REGISTRATION: NCT01517191.


Assuntos
Hospitalização , Vacinas contra Influenza/imunologia , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Estações do Ano , Vacinação , Idoso , Idoso de 80 Anos ou mais , Canadá/epidemiologia , Estudos de Casos e Controles , Feminino , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vírus da Influenza B/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Vigilância em Saúde Pública , Fatores de Risco
3.
Euro Surveill ; 19(9)2014 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-24626207

RESUMO

During the 2013/14 influenza season in Canada, 631 of 654 hospitalisations for laboratory-confirmed influenza enrolled in sentinel hospitals were due to Influenza A. Of the 375 with known subtype, influenza A(H1N1) accounted for 357. Interim unmatched vaccine effectiveness adjusted for age and presence of one or more medical comorbidities was determined by test-negative case-control design to be 58.5% (90% confidence interval (CI): 43.9-69.3%) overall and 57.9% (90% CI: 37.7-71.5) for confirmed influenza A(H1N1).


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Vacinas contra Influenza/administração & dosagem , Influenza Humana/epidemiologia , Influenza Humana/prevenção & controle , Avaliação de Resultados em Cuidados de Saúde , Vigilância de Evento Sentinela , Adolescente , Adulto , Idoso , Canadá/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Vírus da Influenza A Subtipo H1N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/virologia , Laboratórios , Masculino , Pessoa de Meia-Idade , Estações do Ano , Índice de Gravidade de Doença , Adulto Jovem
4.
HIV Clin Trials ; 13(6): 301-7, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23195668

RESUMO

BACKGROUND: HIV reservoirs represent the major obstacles for eradication and are defined as a cell type that allows persistence of replication-competent HIV in patients on optimal long-term antiretroviral therapy (HAART). Several pilot clinical trials have been implemented to assess the value of experimental therapy to reduce reservoir size or eradicate HIV. In order to eradicate HIV, valproic acid was used as a new strategy to increase viral gene expression in the nucleus of infected cells with the expectation of generating a direct cell death or destruction by nearby cytotoxic cells. Previous pilot studies using VPA have showed conflicting results on the ability of VPA to reduce the size of HIV reservoirs. PURPOSE: As the role of VPA on HIV reservoirs remains unclear, we conducted a multicenter clinical trial with a specific study design to obtain optimal information on reservoir changes while exposing the smallest number of individuals to the experimental medication. METHOD: To this aim, a randomized, crossover design with 2 different treatment durations was implemented. By doubling the therapeutic period in one study arm, we were in a position to assess the impact of an extended duration of VPA on the size of the HIV reservoir and to evaluate the duration of treatment effects upon VPA withdrawal in the other arm. However, limitations for this type of study design included the logistical complexity of 2 uneven study arms and longer study duration. CONCLUSION: Despite the absence of demonstrable impact of VPA on reservoir size, such crossover study design should be considered in the early stage testing of novel HIV therapeutics targeted to reduce reservoir size or eradicate HIV.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV/efeitos dos fármacos , Projetos de Pesquisa , Ácido Valproico/uso terapêutico , Estudos Cross-Over , Infecções por HIV/virologia , Humanos
5.
HIV Med ; 13(5): 291-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22276680

RESUMO

OBJECTIVES: Conflicting results have been reported regarding the ability of valproic acid (VPA) to reduce the size of HIV reservoirs in patients receiving suppressive highly active antiretroviral therapy (HAART). In a randomized multicentre, cross-over study, we assessed whether adding VPA to stable HAART could potentially reduce the size of the latent viral reservoir in CD4 T cells of chronically infected patients. METHODS: A total of 56 virologically suppressed patients were randomly assigned either to receive VPA plus HAART for 16 weeks followed by HAART alone for 32 weeks (arm 1; n = 27) or to receive HAART alone for 16 weeks and then VPA plus HAART for 32 weeks (arm 2; n = 29). VPA was administered at a dose of 500 mg twice a day (bid) and was adjusted to the therapeutic range. A quantitative culture assay was used to assess HIV reservoirs in CD4 T cells at baseline and at weeks 16 and 48. RESULTS: No significant reductions in the frequency of CD4 T cells harbouring replication-competent HIV after 16 and 32 weeks of VPA therapy were observed. In arm 1, median (range) values of IU per log(10) billion (IUPB) cells were 2.55 (range 1.20-4.20), 1.80 (range 1.0-4.70) and 2.70 (range 1.0-3.90; P = 0.87) for baseline, week 16 and week 48, respectively. In arm 2, median values of IUPB were 2.55 (range 1.20-4.65), 1.64 (range 1.0-3.94) and 2.51 (range 1.0-4.48; P = 0.50) for baseline, week 16 and week 48, respectively. CONCLUSIONS: Our study demonstrates that adding VPA to stable HAART does not reduce the latent HIV reservoir in virally suppressed patients.


Assuntos
Terapia Antirretroviral de Alta Atividade , Linfócitos T CD4-Positivos/virologia , Inibidores Enzimáticos/uso terapêutico , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Ácido Valproico/uso terapêutico , Latência Viral/efeitos dos fármacos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Cross-Over , Quimioterapia Combinada/métodos , Feminino , Infecções por HIV/virologia , HIV-1/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Carga Viral
6.
Neurochirurgie ; 54(3): 388-98, 2008 May.
Artigo em Francês | MEDLINE | ID: mdl-18462763

RESUMO

Frontal lobe epilepsy surgery is the second most common surgery performed for drug-resistant partial epilepsy. We investigated the longitudinal outcome in a cohort of patients investigated since 1990 with SEEG and modern diagnostic techniques. We reviewed 105 patients who underwent surgery between 1990 and 2005 (mean follow-up, six years; range: one to 17 years) and analyzed the year-per-year follow-up according to Engel's classification. Favorable outcome (Class I) was observed for 70% and this result was stable at least five years after surgery. More than 90% of patients with lesion-related epilepsies (focal cortical dysplasia and dysembryoplastic neuroepithelial tumors) became seizure-free. Less than 50% of patients classified as having cryptogenic epilepsy (defined as normal imaging and neuropathology on surgical specimen) had a favorable outcome. Permanent neurological sequelae were subtle and rare, especially after surgery for dysplasia in eloquent cortex (primary motor cortex). Our data indicate that frontal surgery is a successful treatment in patients when electrophysiological and morphological investigations demonstrate a well-defined epileptogenic zone or lesion to be surgically resected. Progress in electrophysiological and brain-imaging techniques will further improve the selection of frontal lobe epilepsy surgery candidates.


Assuntos
Epilepsia do Lobo Frontal/cirurgia , Procedimentos Neurocirúrgicos , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Dominância Cerebral/fisiologia , Eletroencefalografia , Eletrofisiologia , Epilepsia do Lobo Frontal/etiologia , Epilepsia do Lobo Frontal/patologia , Feminino , Seguimentos , Lateralidade Funcional , Humanos , Lactente , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Córtex Motor/patologia , Procedimentos Neurocirúrgicos/métodos , Seleção de Pacientes , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/psicologia , Convulsões/epidemiologia , Convulsões/fisiopatologia , Resultado do Tratamento
7.
Neurochirurgie ; 54(3): 141-7, 2008 May.
Artigo em Francês | MEDLINE | ID: mdl-18417160

RESUMO

BACKGROUND AND PURPOSE: Animal models have provided very valuable data to specify the physiopathological mechanisms of the various forms of epilepsy. However, the question arises of knowing which of these experimental results are relevant to the human epileptic brain. The development of epileptic surgery makes it possible to directly study the functional properties of human brain tissue in vitro and to analyze the mechanisms underlying seizures and epileptogenesis. We review some of the results obtained over the last few years in our laboratory based on electrophysiological, immunocytochemical and molecular experiments conducted on human brain tissue. RESULTS: This review covers a number of the mechanisms of neuronal synchronizations generating epileptiform discharges, including the role of electrical synapses connecting the inhibitory interneurons, particularly in Taylor-type focal cortical dysplasia and the functional lability of GABAergic inhibition in epileptogenic human cortical tissue, which may sustain triggering and propagation of seizures. Some of these mechanisms have not been described in animal models. CONCLUSIONS: Studies on human tissue, when carefully designed, are necessary to validate the data collected on animal models and will continue to provide us with new and important information on the cerebral changes related to epilepsy. Moreover, these studies allow development of a class of antiepileptic drugs that have a completely new mechanism of action, which could be effective in the treatment of drug-resistant epilepsies.


Assuntos
Epilepsia/patologia , Neurônios/patologia , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Eletrofisiologia , Epilepsia/fisiopatologia , Humanos , Técnicas In Vitro , Interneurônios/fisiologia , Receptores de GABA-A/fisiologia , Convulsões/patologia , Ácido gama-Aminobutírico/fisiologia
8.
Arch Environ Contam Toxicol ; 54(2): 283-91, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17763880

RESUMO

During their formation, fish eggs receive a load of contaminants including polychlorinated biphenyls (PCBs) from their mother and then, after spawning, are exposed to pesticides present in water. This is the first study investigating the interaction between PCBs and organophosphorous pesticides in fish. The effect of diazinon was evaluated in mummichog (Fundulus heteroclitus) larvae produced from eggs differentially treated with 3,3',4,4',5 pentachlorobiphenyl (PCB126). A few hours after fertilization, eggs were treated topically with a solution of PCB126 (100 pg/microl) in dimethyl sulfoxide (DMSO) (Group P), DMSO (Group D), or not treated (Group N). Newly hatched larvae from Groups P and D were exposed to diazinon (125-12,900 ng/L) in saltwater and Group N larvae to saltwater alone. Diazinon caused a dose-responsive inhibition of cholinesterase (ChE) activity at environmentally realistic concentrations (> or =361 ng/L), with up to 85% inhibition at 12,900 ng/L. Body length was also inversely related to diazinon at concentrations > or =361 ng/L and was significantly reduced (by 4%) at 12,900 ng/L compared to controls. Mummichog larvae were highly sensitive to PCB126 with an eightfold induction of the activity of ethoxyresorufin-O-deethylase at a dose of 710 pg PCB126 or 3.6 pg TCDD-TEQ/g wet weight. Treatment with PCB126 also caused a slight reduction in body length but no effect on ChE activity. This study indicates that the effects of PCB126 and diazinon on body length are cumulative because no significant synergistic or antagonistic interactions were observed. Longer term studies with several doses of PCB126 are needed to fully assess the overall impact of joint exposure to diazinon and PCB126 on growth and survival of fish larvae.


Assuntos
Inibidores da Colinesterase/toxicidade , Diazinon/toxicidade , Fundulidae , Inseticidas/toxicidade , Bifenilos Policlorados/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Tamanho Corporal/efeitos dos fármacos , Colinesterases/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Interações Medicamentosas , Fundulidae/anatomia & histologia , Fundulidae/metabolismo , Larva/anatomia & histologia , Larva/efeitos dos fármacos , Larva/metabolismo , Zigoto/efeitos dos fármacos
9.
Eur J Clin Nutr ; 60(11): 1266-76, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16721396

RESUMO

OBJECTIVE: This clinical trial aims to evaluate if natural mixed carotenoids supplementation can improve the health and survival of acquired immunodeficiency syndrome (AIDS) patients. DESIGN: A placebo-controlled, prospective, randomized, double-blind, multicenter clinical trial. SETTING: Community, tertiary care human immunodeficiency virus (HIV) clinics of the Canadian HIV Trials Network (CTN). PARTICIPANTS: Three hundred and thirty-one adults with advanced AIDS on conventional management were recruited during routine clinic visits. INTERVENTIONS: All participants, including 166 controls, received daily oral specially formulated multivitamins including vitamin A and trace elements; 165 treatment group participants received additional daily oral natural mixed carotenoids, equivalent to 120,000 IU (72 mg) of beta-carotene daily. Follow-up was quarterly at routine clinic visits. RESULTS: Mean (s.d.) follow-up was for 13 (6) months. Thirty-six participants died by 18 months. Serum carotene concentration <1.0 micromol/l was present in 16% participants at baseline. Despite variation in carotene content of the treatment medication, serum carotene concentrations increased significantly to twice the baseline levels to 18 months follow-up in participants who received carotenoids treatment compared with controls (P < 0.0001). Although not statistically significant, mortality was increased in participants who did not receive carotenoids treatment compared with those who did (HR time to death 1.76, 95% CI 0.89, 3.47, P = 0.11). In multivariate analysis, survival was significantly and independently improved in those with higher baseline serum carotene concentrations (P = 0.04) or higher baseline CD4 T-lymphocyte counts (P = 0.005). Adjusted mortality was also significantly and independently increased in those who did not receive carotenoids treatment compared with those who did (HR time to death 3.15, 95% CI 1.10, 8.98, P = 0.03). CONCLUSIONS: Low serum carotene concentration is common in AIDS patients and predicts death. Supplementation with micronutrients and natural mixed carotenoids may improve survival by correction of a micronutrient deficiency. Further studies are needed to corroborate findings and elucidate mechanism of action.


Assuntos
Síndrome da Imunodeficiência Adquirida/sangue , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Carotenoides/sangue , Carotenoides/uso terapêutico , Suplementos Nutricionais , Micronutrientes/uso terapêutico , Síndrome da Imunodeficiência Adquirida/mortalidade , Adulto , Idoso , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Carotenoides/administração & dosagem , Progressão da Doença , Método Duplo-Cego , Feminino , Humanos , Masculino , Micronutrientes/administração & dosagem , Pessoa de Meia-Idade , Análise Multivariada , Análise de Sobrevida , Carga Viral
10.
AIDS Care ; 17(4): 493-504, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16036235

RESUMO

The aim of this longitudinal study was to identify the determinants of adherence to antiretroviral therapy (ART) in HIV patients over a period of 12 months. A total of 376 individuals living with HIV treated with ART participated in the study. Data were collected at baseline and at three, six, nine and 12 months. Variables assessed were adherence, attitude, outcome expectancies, self-efficacy, patient satisfaction with the relationship with their physician, provision of social support, optimism, CD4 cell count, viral load and side effects. Predictors of adherence in the Generalized Estimated Equation (GEE) were: high perception of self-efficacy (OR=1.68; 95%CI 1.27-2.22), positive attitude towards taking medication (OR=1.56; 95%CI 1.18-2.06), not living alone (OR=1.47; 95%CI 1.04-2.08) and being a male (OR=2.81; 95%CI 1.47-5.34). Subsequent analysis showed that a positive attitude towards taking medication was associated with a high level of patient satisfaction with their physician, high perceived social support, being optimistic, living with HIV for five years or less and experiencing no side effects. Also, a strong sense of self-efficacy was associated with positive perception of social support, high level of patient satisfaction with their physician and not living alone. These results suggest that interventions aimed at improving adherence to ART should focus on reinforcing self-efficacy and developing a positive attitude towards taking medication.


Assuntos
Antirretrovirais/uso terapêutico , Atitude Frente a Saúde , Infecções por HIV/tratamento farmacológico , Motivação , Cooperação do Paciente , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
11.
Neuroscience ; 122(2): 437-47, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14614908

RESUMO

A somatostatin deficit occurs in the cerebral cortex of Alzheimer's disease patients without a major loss in somatostatin-containing neurons. This deficit could be related to a reduction in the rate of proteolytic processing of peptide precursors. Since the two proprotein convertases (PC)1 and PC2 are responsible for the processing of neuropeptide precursors directed to the regulated secretory pathway, we examined whether they are involved first in the proteolytic processing of prosomatostatin in mouse and human brain and secondly in somatostatin defect associated with Alzheimer's disease. By size exclusion chromatography, the cleavage of prosomatostatin to somatostatin-14 is almost totally abolished in the cortex of PC2 null mice, while the proportions of prosomatostatin and somatostatin-28 are increased. By immunohistochemistry, PC1 and PC2 were localized in many neuronal elements in human frontal and temporal cortex. The convertases levels were quantified by Western blot, as well as the protein 7B2 which is required for the production of active PC2. No significant change in PC1 levels was observed in Alzheimer's disease. In contrast, a marked decrease in the ratio of the PC2 precursor to the total enzymatic pool was observed in the frontal cortex of Alzheimer patients. This decrease coincides with an increase in the binding protein 7B2. However, the content and enzymatic activity of the PC2 mature form were similar in Alzheimer patients and controls. Therefore, the cortical somatostatin defect is not due to convertase alteration occuring during Alzheimer's disease. Further studies will be needed to assess the mechanisms involved in somatostatin deficiency in Alzheimer's disease.


Assuntos
Doença de Alzheimer/enzimologia , Pró-Proteína Convertase 2/fisiologia , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional/fisiologia , Somatostatina/biossíntese , Somatostatina/deficiência , Somatostatina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Análise de Variância , Animais , Córtex Cerebral/enzimologia , Córtex Cerebral/patologia , Feminino , Humanos , Modelos Lineares , Masculino , Camundongos , Camundongos Knockout , Pró-Proteína Convertase 2/deficiência , Pró-Proteína Convertase 2/genética , Precursores de Proteínas/genética , Processamento de Proteína Pós-Traducional/genética , Ratos , Ratos Sprague-Dawley , Somatostatina/genética
12.
Environ Toxicol ; 17(3): 160-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12112624

RESUMO

Immune function in bivalves can be adversely affected by long-term exposure to environmental contaminants. Investigating alterations in immunity can therefore yield relevant information about the relationship between exposure to environmental contaminants and susceptibility to infectious diseases. We have developed a rapid, cost-effective, and miniaturized immunocompetence assay to evaluate the phagocytic activity, viability, and concentration of hemocytes in freshwater and marine bivalves. Preliminary experiments were performed to optimize various aspects of the assay including 1) the time required for adherence of hemocytes to polystyrene microplate wells, 2) the time required for internalization of fluorescent bacteria, 3) the ratio of hemocytes to fluorescent bacteria in relation to phagocytosis, 4) hemolymph plasma requirements, and 5) the elimination of fluorescence from (noninternalized) bacteria adhering to the external surface of hemocytes. The results of these experiments showed the optimal adherence time for hemocytes in microplate wells to be 1 h, that phagocytosis required at least 2 h of contact with fluorescently labeled E. coli cells, that the number of fluorescent E. coli cells had a positive effect on phagocytic activity, that at least 2.5 million cells/mL were required to measure a significant intake, and that a linear increase in uptake of bacteria (R = 0.91; p < 0.01) could be obtained with concentrations of up to 1.3 x 10(6) hemocytes/mL. Afterward, the assay was used in two field studies to identify sites having the potential to affect the immunocompetence of bivalves. The first study was conducted on Mya arenaria clams collected at selected contaminated sites in the Saguenay River (Quebec, Canada), and the second examined Elliptio complanata freshwater bivalves that had been exposed to a municipal effluent plume in the St. Lawrence River (Quebec, Canada). In the Saguenay River field study a significant increase in phagocytosis was observed at sites closest to polluted areas. Phagocytotic activity varied over time and was highest during the warmest months (June, July, and August), closely paralleling the spawning period of Mya arenaria clams. In contrast, a drop in phagocytic activity was observed in Elliptio complanata mussels exposed to surface water 4 km downstream of a major municipal effluent plume, with a concomitant increase in the number of hemocytes in the hemolymph. It appears that both immunosuppressive and immunostimulative effects are likely to occur in the field and that responses will be influenced by the type and intensity of contaminants at play.


Assuntos
Bivalves/imunologia , Exposição Ambiental , Imunocompetência/efeitos dos fármacos , Fagocitose , Poluentes Químicos da Água/efeitos adversos , Animais , Bioensaio/métodos , Análise Custo-Benefício , Hemócitos/fisiologia , Imunocompetência/fisiologia
13.
Environ Toxicol ; 17(3): 170-86, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12112625

RESUMO

A spatial and temporal survey of six sites in the Saguenay Fjord and of one adjacent site in the St. Lawrence River estuary (Quebec, Canada) was undertaken to study the possible effects of anthropogenic contaminant input on soft-shell clam (Mya arenaria) populations. Bivalve sampling sites were selected because they reflected a range of areas representative of either no known (or apparent) pollution sources or of areas potentially influenced by different gradients and types of contamination sources. The most upstream site selected in the Saguenay Fjord, nearest to a highly populated and industrialized sector, and the most downstream site, near its mouth with the St. Lawrence River estuary, spanned a distance of some 70 km and encompassed the entire intertidal area suitable for Mya arenaria habitat. To measure effects in collected animals, we used a comprehensive battery of biomarkers composed of metallothionein-like proteins (MT), 7-ethoxyresorufin O-deethylase activity (EROD), DNA damage (DD), lipid peroxidation (LPO), vitellinlike proteins (Vn), phagocytosis (PHAG), nonspecific esterase (NspE) activity, and condition factor (weight-to-length ratio of clams). Vn, PHAG, DD, and NspE biomarkers were assayed in hemolymph (or hemocytes), whereas others (MT, EROD, LPO) were determined in the digestive gland. Whole-tissue metal content was also quantified in clams collected in the spatial survey. The spatial survey conducted in June 1997 showed significant effects at all sites, and principal component analysis indicated in addition that the more important responses were linked to the MT, LPO, and NspE biomarkers. Clams collected from sites closest to the upstream reaches of the fjord generally displayed higher levels of tissue metals (cadmium, manganese), as well as greater responses of NspE activity, MT, LPO, and PHAG. Animals collected from sites influenced by municipal wastewaters had higher levels of Vn, suggesting the presence of environmental estrogens. The results of the temporal survey (six monthly samplings of clams at three sites from May through October, 1997) showed that the bivalve reproductive cycle (vitellogenesis and spawning) can modulate the expression of several biomarkers. Vn levels, for example, were positively correlated with DD and EROD and negatively correlated with MT, suggesting that reproduction can influence the susceptibility of clams to some contaminants. Discrimination analysis over the 6 months of sampling revealed that the mean value of the discriminant function changed significantly over time, suggesting important changes in the relative contribution of each biomarker. In short, this study has provided evidence that clam populations in the Saguenay Fjord are impacted by multiple sources of contamination whose effects can be modulated by reproduction.


Assuntos
Biomarcadores/análise , Bivalves/fisiologia , Monitoramento Ambiental/métodos , Poluentes da Água/efeitos adversos , Animais , Citocromo P-450 CYP1A1/análise , Dano ao DNA , Esterases/análise , Hemócitos , Hemolinfa , Resíduos Industriais , Peroxidação de Lipídeos , Metalotioneína/análise , Fagocitose , Quebeque , Poluentes da Água/análise
14.
Brain Res ; 939(1-2): 52-64, 2002 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-12020851

RESUMO

The presence of GABA and galanin in histaminergic neurons was previously reported in the rodent brain but whether such co-localizations also occur in the human brain was not known. We used in situ hybridization histochemistry and immunohistochemistry to study the co-localization of histamine with GABA and galanin in neurons of the tuberomamillary nucleus of adult human posterior hypothalamus. On consecutive formalin-fixed paraffin-embedded sections, co-localization was assessed using the in situ hybridization for L-histidine decarboxylase mRNA and immunocytochemistry for glutamate decarboxylase-67 kDa or galanin in the two profiles of same cell. The pattern of distribution and number of histaminergic neurons identified by in situ hybridization of the synthesizing enzyme gene transcripts were in accordance with data reported for histamine immunoreactivity. The great majority of neurons within the main divisions of the tuberomamillary nucleus containing L-histidine decarboxylase mRNA was also immunoreactive for glutamate decarboxylase-67 kDa. The range of co-localization of the two markers varied from 72% in the lateral part, to 75-87% in the medial part and 83-88% in the ventral part. In contrast, no cell containing L-histidine decarboxylase mRNA was immunoreactive for galanin. We conclude that tuberomamillary neurons in human co-express histamine with GABA but, unlike the neurons in rodents, do not express galanin, indicating that neurotransmitter co-localization patterns differ in the two species.


Assuntos
Galanina/metabolismo , Histamina/metabolismo , Região Hipotalâmica Lateral/metabolismo , Ácido gama-Aminobutírico/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Autopsia , Feminino , Galanina/análise , Glutamato Descarboxilase/análise , Histidina Descarboxilase/análise , Histidina Descarboxilase/genética , Humanos , Região Hipotalâmica Lateral/enzimologia , Imuno-Histoquímica , Hibridização In Situ , Isoenzimas/análise , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/análise
15.
J Neural Transm (Vienna) ; 109(3): 293-306, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11956952

RESUMO

The histaminergic H3-receptor (H3R) controls histamine synthesis and release in the tuberomamillary nucleus. We evaluated the effects of stimulating or blocking of H(3)R on glutamate-decarboxylase 67 kDa (GAD-67) and galanin mRNA expression, two histamine co-transmitters.After in situ hybridization histochemistry (ISHH), we observed a colocalization of 100% between histidine decarboxylase (HDC) and GAD-67 or H3R and of 80 to 97% with galanin. Adult rats received an H3R agonist ((R)alpha-Methylhistamine) or antagonist (ciproxifan) and were sacrificed 1 or 3 hours later. Treatment effects on HDC, galanin and GAD-67 mRNA were studied by quantitative ISHH on serial sections. Treatment with the H3R agonist known to decrease histamine neuron activity initially reduced HDC and galanin gene expression but an inverse change, presumably reflecting a compensatory mechanism, was observed after 3 h on both markers. In contrast, the H3R antagonist known to activate histamine neurons, had opposite effects on the two markers, suggesting that co-transmitters are submitted to independent control mechanisms. Furthermore, GAD-67 mRNA levels were not significantly modified by these treatments.


Assuntos
Galanina/genética , Histamina/biossíntese , Hipotálamo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Receptores Histamínicos H3/efeitos dos fármacos , Ácido gama-Aminobutírico/biossíntese , Animais , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Glutamato Descarboxilase/genética , Agonistas dos Receptores Histamínicos/farmacologia , Antagonistas dos Receptores Histamínicos/farmacologia , Histidina Descarboxilase/genética , Região Hipotalâmica Lateral/citologia , Região Hipotalâmica Lateral/efeitos dos fármacos , Região Hipotalâmica Lateral/metabolismo , Hipotálamo/citologia , Hipotálamo/metabolismo , Imidazóis/farmacologia , Isoenzimas/genética , Masculino , Metilistaminas/farmacologia , Neurônios/citologia , Neurônios/metabolismo , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Receptores Histamínicos H3/metabolismo
16.
Br J Ophthalmol ; 85(5): 576-81, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11316720

RESUMO

AIMS: To compare the efficacy and safety of famciclovir with aciclovir for the treatment of ophthalmic zoster. METHODS: Randomised, double masked, aciclovir controlled, parallel group in 87 centres worldwide including 454 patients with ophthalmic zoster of trigeminal nerve (V(1)) comprised the intent to treat population. Oral famciclovir 500 mg three times daily or oral aciclovir 800 mg five times daily for 7 days. Assessments included day 0 (screening), days 3 and 7 (during treatment), days 10, 14, 21, 28 and monthly thereafter, up to 6 months (follow up). Proportion of patients who experienced ocular manifestations, severe manifestations and non-severe manifestations; loss of visual acuity was the main outcome measure. RESULTS: The percentage of patients who experienced one or more ocular manifestations was similar for famciclovir (142/245, 58.0%) and aciclovir (114/196, 58.2%) recipients, with no significant difference between groups (OR 0.99; 95% CI 0.68, 1.45). The percentage of patients who experienced severe and non-severe manifestations was similar between groups, with no significant difference. The prevalence of individual ocular manifestations was comparable between groups. There was no significant difference between groups for visual acuity loss. CONCLUSION: Famciclovir 500 mg three times daily was well tolerated and demonstrated efficacy similar to aciclovir 800 mg five times daily.


Assuntos
2-Aminopurina/análogos & derivados , 2-Aminopurina/uso terapêutico , Aciclovir/uso terapêutico , Antivirais/uso terapêutico , Herpes Zoster Oftálmico/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalos de Confiança , Método Duplo-Cego , Famciclovir , Feminino , Herpes Zoster Oftálmico/complicações , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Resultado do Tratamento , Acuidade Visual
17.
Environ Pollut ; 111(1): 29-43, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11202713

RESUMO

Levels of tris (4-chlorophenyl) methanol (TCPM) and its presumed precursor tris (4-chlorophenyl) methane (TCPMe) are reported in marine mammals from the Estuary and Gulf of St. Lawrence, Canada. These compounds were measured in blubber samples of seals and whales using ion trap mass spectrometry (MS/MS) detection. Detectable concentrations of both TCPM and TCPMe were observed in all of the samples analysed. Concentrations of these compounds varied with species ranging from 1.7 to 153 and from 1.3 to 50.6 ng/g lipid wt. for TCPM and TCPMe, respectively. TCPM was from 1.3 to 10 times more concentrated than TCPMe. The highest levels of both TCPM and TCPMe were observed in adult male beluga whales (Delphinapterus leucas) from the St. Lawrence Estuary, while adult female beluga whales from the same area showed levels similar to those in the seals examined. Among the four seal species investigated, TCPM and TCPMe levels were the highest in grey (Halichoerus grypus) and hooded (Cystophora cristata) seals, and lowest in harp seals (Phoca groenlandica). Intermediate levels were found in harbour seals (Phoca vitulina); however, their concentrations might be underestimated considering the younger mean age of these animals. Ratios of both 4,4'-DDE/sigma DDT and TCPM/sigma TCP were very similar between animals from the same species. Strong correlations between sigma TCP and sigma DDT were also observed for each species of mammals, most likely indicating that both sigma TCP and sigma DDT are bioaccumulated in marine mammals. The relationships between sigma DDT and sigma TCP also demonstrate that sigma TCP are less bioaccumulated than sigma DDT by the marine mammal species examined.


Assuntos
Tecido Adiposo/química , Focas Verdadeiras , Compostos de Tritil/análise , Poluentes Químicos da Água/análise , Baleias , Animais , Monitoramento Ambiental , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Quebeque
18.
Lancet ; 355(9218): 1845-50, 2000 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-10866439

RESUMO

BACKGROUND: Use of some antiviral drugs for influenza infection is limited by potential rapid emergence of resistance. We studied the efficacy and safety of oseltamivir, the oral prodrug of the neuraminidase inhibitor GS4071, in adults with naturally acquired laboratory-confirmed influenza. METHODS: We did a randomised controlled trial of 726 previously healthy non-immunised adults with febrile influenza-like illness of up to 36 h duration. Patients were assigned oral oseltamivir 75 mg (n=243), oseltamivir 150 mg (n=245), or placebo (n=238) twice daily for 5 days. We assessed recovery by questionnaire and temperature recordings. The primary endpoint was time to resolution of illness in influenza-infected patients. FINDINGS: 475 (66%) patients had confirmed infection. Duration of illness was significantly shorter by 29 h (25% reduction, median duration 87.4 h [95% CI 73.3-104.7], p=0.02) with oseltamivir 75 mg and by 35 h (30%, 81.8 h [68.2-100.0], p=0.01) with oseltamivir 150 mg than with placebo (116.5 h [101.5-137.8]). The effect of oseltamivir was apparent within 24 h of the start of treatment. In patients treated within 24 h of symptom onset, symptoms were alleviated 43 h (37% reduction) and 47 h (40%) earlier with oseltamivir 75 mg and 150 mg, respectively, compared with placebo (75 mg 74.5 h [68.2-98.0], p=0.02; 150 mg 70.7 h [54.0-89.4], p=0.01; placebo 117.5 h [103.0-143.8]). Oseltamivir was associated with lower [corrected] symptom scores, less viral shedding, and improved health, activity, and sleep quality, and was well tolerated. INTERPRETATION: Oseltamivir was effective and well tolerated in the treatment of natural influenza infection in adults. The efficacy, tolerability, and ease of administration warrant further investigation in children, elderly patients, and at-risk patients.


Assuntos
Acetamidas/uso terapêutico , Antivirais/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Influenza Humana/tratamento farmacológico , Acetamidas/administração & dosagem , Administração Oral , Adulto , Antivirais/administração & dosagem , Método Duplo-Cego , Esquema de Medicação , Inibidores Enzimáticos/administração & dosagem , Feminino , Humanos , Influenza Humana/classificação , Masculino , Neuraminidase/antagonistas & inibidores , Oseltamivir , Pró-Fármacos/uso terapêutico , Índice de Gravidade de Doença , Inquéritos e Questionários
19.
J Infect Dis ; 181(4): 1471-4, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10762579

RESUMO

The antiviral and clinical effects of inhaled zanamivir (10 mg twice daily for 5 days, started within the first or second day of a flulike illness) were evaluated in a randomized, placebo-controlled trial during the 1997-1998 influenza season in Canada. Pharyngeal secretions were collected with swabs every 12 h during 6 days, and symptoms were self-evaluated twice daily during 14 days. After only 12 h of treatment (1 dose), median virus titers decreased by 1.0 log10 TCID50/mL in the zanamivir group (n=17), compared with a 0. 42-log10 increase in the placebo group (n=10; P=.08). This was associated with a 4.5-day (47.4%) reduction in the median time to alleviation of all significant flu symptoms in the zanamivir recipients (P=.03 after adjusting for the initial virus titer and the time between onset of symptoms and treatment). Resistance to zanamivir was not detected in virus isolates by either phenotypic or genotypic assays.


Assuntos
Antivirais/uso terapêutico , Influenza Humana/tratamento farmacológico , Ácidos Siálicos/uso terapêutico , Administração por Inalação , Adulto , Antivirais/administração & dosagem , Canadá , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/uso terapêutico , Guanidinas , Humanos , Neuraminidase/antagonistas & inibidores , Piranos , Ácidos Siálicos/administração & dosagem , Zanamivir
20.
Glia ; 26(2): 176-85, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10384882

RESUMO

Edg-2 is an heptahelical receptor whose spatio-temporal distribution during rat brain development is consistent with a role in the control of myelination. We have now identified two splice variants of Edg-2 mRNA in rat brain that encode two receptor isoforms differing by a stretch of 18 amino acids in the NH2-terminal extracellular tail of the receptor. Prenatally (i.e., before oligodendrocyte myelination), the two variants detected by selective in situ hybridization are equally abundant, vary in parallel, and remain restricted to proliferative zones in the brain. Postnatally, the long isoform becomes predominant in myelinating structures, where its abundance increases sharply during the period of myelination. In the adult human brain, only the long variant was detected, while in situ hybridization showed it selectively expressed in the white matter and in clusters of cells showing features of oligodendrocytes of the temporal cerebral cortex. Consequently, the human Edg-2 gene was studied to assess its possible contribution in inherited neuropathies. The coding sequence was found to be contained in three exons and to map to chromosome 9q31.3-32 by using radiation hybrid panel and Yeast-Artificial Chromosomes. Two intragenic bi-allelic polymorphisms and a rare mutation were identified. As a first application to molecular genetic studies, they were used to exclude the Edg-2 gene in six families with phenotype of demyelinating Charcot-Marie-Tooth disease of unknown origin.


Assuntos
Encéfalo/metabolismo , Bainha de Mielina/fisiologia , Neurônios/metabolismo , Proteínas Nucleares/metabolismo , Receptores de Superfície Celular , Receptores Acoplados a Proteínas G , Fatores de Transcrição/metabolismo , Adulto , Sequência de Aminoácidos/genética , Animais , Sequência de Bases/genética , Encéfalo/citologia , Doença de Charcot-Marie-Tooth/genética , Doença de Charcot-Marie-Tooth/metabolismo , Mapeamento Cromossômico , Clonagem Molecular , Feminino , Ligação Genética/genética , Genoma , Humanos , Dados de Sequência Molecular , Proteínas Nucleares/genética , Linhagem , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ratos , Receptores de Ácidos Lisofosfatídicos , Fatores de Transcrição/genética
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