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1.
Environ Sci Technol ; 52(11): 6197-6207, 2018 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-29737158

RESUMO

Hexabromocyclododecane (HBCDD) is a high concern environmental pollutant due to its persistent, bioaccumulative, and toxic properties. The spatial distribution of HBCDD was investigated in top predator fish (lake trout, walleye, or brook trout) collected in 2013 ( n = 165) from 19 sampling sites and in 2015 ( n = 145) from 20 sites across Canada. HBCDD was measurable in at least one sample at each sampling site regardless of sampling year with the exception of walleye from the south basin of Lake Winnipeg (2013). Sampling sites in or near the Laurentian Great Lakes had greater ΣHBCDD concentrations compared to locations to the west or east. The greatest mean ΣHBCDD concentration was 72.6 ng/g lw in fish from Lake Huron-Goderich (2015). Regardless of the sampling sites, α-HBCDD was the dominant congener followed by γ-HBCDD, whereas ß-HBCDD was barely detectable. In fish from the same waterbody there were comparable α/γ isomer concentration ratios. The greatest ratio was 20.8 in fish from Lake Ontario, whereas the lowest ratio was 6.3 for fish from Lac Memphrémagog (Québec) likely related to more recent emissions of a technical HBCDD mixture. Temporal trends of HBCDD in lake trout from Lake Ontario showed a significant decreasing trend for γ-HBCDD with a half-life estimate of 10 years over a 36-year period (1979-2015), and for α-HBCDD with a half-life of 11 years over the years of 2008 to 2015. The proportion of α-HBCDD to ΣHBCDD increased significantly during 1979 to 2015. The present study provided novel information on the isomer-specific HBCDDs in Canada freshwater fish.


Assuntos
Lagos , Poluentes Químicos da Água , Animais , Canadá , Monitoramento Ambiental , Hidrocarbonetos Bromados , Ontário , Quebeque
2.
Environ Pollut ; 193: 254-261, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25063913

RESUMO

Whole body homogenates of Lake Trout (Salvelinus namaycush) or Walleye (Sander vitreus) collected from Canadian lakes were screened for organophosphate flame retardant (OPFR) and organosiloxane compounds. Six OPFR and five siloxane compounds were detected above quantitation limits in at least one individual fish from sampled lakes. The OPFRs, tris(2-chloroethyl) phosphate (TCEP) and tris(2-butoxyethyl) phosphate (TBOEP), were most frequently quantified with concentrations ranging from <0.07 to 9.8 ng/g (ww). Levels of TBOEP were highest in fish from the Great Lakes region while TCEP was detected only in fish from the northernmost lakes in our network. Concentrations of the cyclic siloxanes, octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6), were above quantitation limits in all fish. D5 was the most abundant siloxane across all sampling locations with the highest concentrations (45-719 ng/g ww) observed in Lake Trout from the western end of Lake Ontario near the mouth of the Niagara River.


Assuntos
Retardadores de Chama/análise , Organofosfatos/análise , Compostos Organofosforados/análise , Percas/metabolismo , Siloxanas/análise , Truta/metabolismo , Poluentes Químicos da Água/análise , Animais , Canadá , Retardadores de Chama/metabolismo , Água Doce/análise , Ontário , Organofosfatos/metabolismo , Compostos Organofosforados/metabolismo , Siloxanas/metabolismo , Poluentes Químicos da Água/metabolismo
3.
Ann Cardiol Angeiol (Paris) ; 63(2): 83-8, 2014 Apr.
Artigo em Francês | MEDLINE | ID: mdl-24492012

RESUMO

INTRODUCTION: Few studies in sub-Saharan Africa were interested in resistant hypertension. The objectives of this study were to determine the frequency of resistant hypertension in hypertensive black African population, and to describe its clinical and therapeutic features. PATIENTS AND METHODS: From May 1, 2010 to May 31, 2012, we included consecutively hypertensive followed in two hospitals in the city of Ouagadougou, under antihypertensive treatment at optimum dose and observant. Patients whose blood pressure was uncontrolled despite a triple antihypertensive therapy at the optimal dose including a diuretic associated with dietary measures have received ambulatory blood pressure monitoring. Following this examination, patients whose blood pressure was ≥135/85mmHg during the day and/or ≥120/70mmHg at night were considered resistant hypertension. We investigated the cardiovascular risk factors as well as target organ damages. We combined spironolactone 50mg in treatment when absence of contra-indication appreciated the evolution of blood pressure under this treatment. The measurement of plasma renin activity was not performed. Statistical analysis was performed using SPSS Version 17 for Windows. RESULTS: We included 692 patients with 14.6% of resistant hypertension. The average age of patients was 54.8±11.1years in the general population, 56.5±11.8years in the subgroup of non-resistant hypertension and 64.2±5.4years in the subgroup of resistant hypertension. The symptoms were represented by headache (11.9%), dizziness (9.9%) and chest pain (8.9%). Modifiable cardiovascular risk factors were dominated by dyslipidemia, diabetes and obesity/overweight. These risk factors were significantly more frequent in the subgroup of resistant hypertension. The global cardiovascular risk was high in 24.9% of cases in the general population, 22.5% in the subgroup of non-resistant hypertension and 38.6% in the subgroup of resistant hypertension. The target organ damages were significantly more frequent in the same subgroup of resistant hypertension. After addition of spironolactone, 21.8% of resistant hypertensive patients were controlled. CONCLUSION: This study shows that resistant hypertension is common in black Africans. It is mostly subjects of the sixth decade, with limited economic income and living in rural areas. In the absence of contra-indication, spironolactone contributed to decrease the morbidity of this pathology.


Assuntos
População Negra/estatística & dados numéricos , Hipertensão/etnologia , Adulto , Idoso , Anti-Hipertensivos/uso terapêutico , Determinação da Pressão Arterial , Monitorização Ambulatorial da Pressão Arterial , Índice de Massa Corporal , Burkina Faso/epidemiologia , Países em Desenvolvimento , Complicações do Diabetes , Diuréticos/uso terapêutico , Quimioterapia Combinada , Dislipidemias/complicações , Feminino , Seguimentos , Hospitais Municipais , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Obesidade/complicações , Prevalência , Fatores de Risco
4.
Environ Pollut ; 186: 141-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24374064

RESUMO

We examine the concentrations and food web biomagnification of three cyclic volatile methylsiloxanes (cVMS) octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclohexasiloxane (D6) using aquatic biota collected from Lake Erie. Concentrations of cVMS in biota were within the range reported for other studies of cVMS in aquatic biota. Trophic magnification factors (TMF) were assessed in various food web configurations to investigate the effects of food web structure. TMF estimates were highly dependent on the inclusion/exclusion of the organisms occupying the highest and lowest trophic levels and were >1 for D4 and D5, indicating biomagnification, in only 1 of the 5 food web configurations investigated and were <1 in the remaining 4 food web configurations. TMF estimates for PCB180 were also dependant on food web configuration, but did not correspond with those obtained for cVMS materials. These differences may be attributed to environmental exposure and/or lipid partitioning differences between PCB180 and cVMS.


Assuntos
Cadeia Alimentar , Lagos/química , Siloxanas/análise , Poluentes Químicos da Água/análise , Biota , Canadá , Monitoramento Ambiental , Siloxanas/metabolismo , Poluentes Químicos da Água/metabolismo
5.
Ann Cardiol Angeiol (Paris) ; 62(1): 38-42, 2013 Feb.
Artigo em Francês | MEDLINE | ID: mdl-22677180

RESUMO

INTRODUCTION: Hypertension in black is more frequent with early onset and clinically more severe. The blood pressure control and the decrease of global cardiovascular risk are two main goals of the treatment of hypertension. The objectives of this study were to determine the proportion of uncontrolled hypertension in hypertensive patients followed as outpatients and to investigate the factors associated with poor control. PATIENTS AND METHODS: This is a descriptive cross-sectional study including 456 hypertensive patients known and followed as outpatients. Blood pressure measurement was performed between 8 am and 12 noon both arms in the supine position, after a compliance averaging 8 minutes of rest. We searched for conventional cardiovascular risk factors (age superior or equal to 45 years for men and superior or equal to 55 for women, physical inactivity, overweight/obesity, smoking, diabetes and dyslipidemia) and calculated the global cardiovascular risk according to the Framingham model. Was regarded as uncontrolled high blood pressure SBP superior or equal to 140 mmHg and/or DBP superior or equal to 90 mmHg. Univariate analysis and multivariate logistic regression (using SPSS program version 17) were conducted to look for factors associated with poor blood pressure control. RESULTS: We recruited 456 hypertensive patients including 259 women (56.8%). Modifiable cardiovascular risk factors also hypertension were dominated by dyslipidemia (29.8%) and diabetes (24.6%). The global cardiovascular risk calculated using the Framingham model was low in 21.3%, moderate in 34.0%, high in 24.8% and very high in 19.9% of cases. The proportion of uncontrolled hypertension was 54.2% (n=247 including 126 women and 121 men). This poor blood pressure control was associated (multivariate analysis) at age superior or equal to 60 years, low socioeconomic status, high to very high cardiovascular risk, antihypertensive monotherapy, treatment duration superior or equal to 10 years, an associated treatment and non-compliance therapy. CONCLUSION: More than half of hypertensive patients in our study were not adequately controlled on antihypertensive therapy. Factors of poor control were age superior or equal to 60 years, low socioeconomic status, high to very high cardiovascular risk, antihypertensive monotherapy, treatment duration superior or equal to 10 years, an associated treatment and non-compliance therapy.


Assuntos
Anti-Hipertensivos/uso terapêutico , População Negra , Determinação da Pressão Arterial/estatística & dados numéricos , Países em Desenvolvimento , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Adulto , Idoso , Assistência Ambulatorial/estatística & dados numéricos , Burkina Faso , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/etiologia , Terapia Combinada , Estudos Transversais , Feminino , Comportamentos Relacionados com a Saúde , Indicadores Básicos de Saúde , Humanos , Hipertensão/etnologia , Hipertensão/etiologia , Estilo de Vida , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Fatores Socioeconômicos
6.
Environ Toxicol Chem ; 30(7): 1564-75, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21523816

RESUMO

A nationwide study was conducted to examine concentrations of polybrominated diphenyl ethers (PBDEs) in top predatory fish, with a focus on lake trout (Salvelinus namaycush), across Canada, and to explore possible influences of food web processes. Concentrations of the three most abundant PBDE homolog groups (tetra-, penta-, and hexa-PBDEs) were, for the most part, higher in Great Lakes and Lake Champlain fish compared with fish from other systems. The Canadian Federal Environmental Quality Guideline for the penta-homolog was exceeded in 70% of the fish examined. However, virtually no guideline exceedances were found for other congeners. In general, PBDE-47 (a representative lower brominated congener) was significantly and positively correlated with fish length, weight, age, lipid content, and stable isotopes of nitrogen and carbon. Significant differences in the slopes of the PBDE-47/covariate relationships between sites prevented concentrations from being adjusted using an analysis of covariance (ANCOVA). However, plots showed that elevated concentrations of PBDE-47 in Great Lakes and Lake Champlain fish remained after accounting for the influence of covariates. In contrast, for PBDE-183 (a representative higher brominated congener), the relationships between fish concentrations and covariates were not consistent, which could be a result of biotransformation being more important in controlling its bioaccumulation. The data from the current study show an overall disconnect between fish PBDE concentrations and likely loadings, which may be caused by differences in food web processes between systems. Continued long-term fish contaminant monitoring is needed to evaluate potential risk to fish and their consumers. However, we also recommend sediment sampling and focused food web studies to provide information on PBDE inputs to the systems and mechanisms of biomagnification, respectively.


Assuntos
Éteres Difenil Halogenados/metabolismo , Truta/metabolismo , Poluentes Químicos da Água/metabolismo , Poluição Química da Água/estatística & dados numéricos , Análise de Variância , Animais , Biotransformação , Canadá , Monitoramento Ambiental , Cadeia Alimentar , Água Doce/química , Éteres Difenil Halogenados/análise , Poluentes Químicos da Água/análise
7.
Reprod Biol Endocrinol ; 8: 25, 2010 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-20226040

RESUMO

BACKGROUND: The study was designed to test the hypothesis that granulosa cell (GC) gene expression response differs between recombinant FSH and human menopausal gonadotropin (hMG) stimulation regimens. METHODS: Females < 35 years-old undergoing IVF for tubal or male factor infertility were prospectively randomized to one of two stimulation protocols, GnRH agonist long protocol plus individualized dosages of (1) recombinant (r)FSH (Gonal-F) or (2) purified human menopausal gonadotropin (hMG; Menopur). Oocytes were retrieved 35 h post-hCG, and GC were collected. Total RNA was extracted from each GC sample, biotinylated cRNA was synthesized, and each sample was run on Human Genome Bioarrays (Applied Microarrays). Unnamed genes and genes with <2-fold difference in expression were excluded. RESULTS: After exclusions, 1736 genes exhibited differential expression between groups. Over 400 were categorized as signal transduction genes, approximately 180 as transcriptional regulators, and approximately 175 as enzymes/metabolic genes. Expression of selected genes was confirmed by RT-PCR. Differentially expressed genes included A kinase anchor protein 11 (AKAP11), bone morphogenetic protein receptor II (BMPR2), epidermal growth factor (EGF), insulin-like growth factor binding protein (IGFBP)-4, IGFBP-5, and hypoxia-inducible factor (HIF)-1 alpha. CONCLUSIONS: Results suggest that major differences exist in the mechanism by which pure FSH alone versus FSH/LH regulate gene expression in preovulatory GC that could impact oocyte maturity and developmental competence.


Assuntos
Hormônio Foliculoestimulante/farmacologia , Células da Granulosa/efeitos dos fármacos , Menotropinas/farmacologia , Indução da Ovulação/métodos , Adulto , Feminino , Hormônio Foliculoestimulante/uso terapêutico , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/metabolismo , Humanos , Infertilidade/terapia , Masculino , Menotropinas/uso terapêutico , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Recombinantes/farmacologia , Proteínas Recombinantes/uso terapêutico , Adulto Jovem
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