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1.
Acute Med ; 17(3): 156-159, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30129950

RESUMO

No reported cases to date describe herpes simplex virus (HSV) myelitis in association with cancer and chemo-radiation. We report a case of sub-acute HSV myelitis in a 54-year-old man receiving chemo-radiation with 5-flourouracil for esophageal cancer who presented to the emergency department with increasing numbness in both lower limbs that gradually spread to waist level. Magnetic resonance imaging with gadobutrol contrast 1 week later showed transverse myelitis involving the dorsal columns. Radiation-induced myelitis was suspected, and the patient was initially treated with dexamethasone; however, CSF analysis revealed HSV myelitis. Treatment with antivirals resolved much of the numbness. HSV myelitis can be confused with complications of radiation or malignancy in patients presenting with focal neurological deficits.

2.
Environ Int ; 42: 1-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21450345

RESUMO

Occurrence, removal, consumption and environmental risks of sixteen antibiotics were investigated in several sewage treatment plants (STPs) featuring different treatment levels in Hong Kong, China. Cefalexin, ofloxacin and erythromycin-H(2)O were predominant with concentrations of 1020-5640, 142-7900 and 243-4740 ng/L in influent, respectively; their mass loads were comparable to levels reported in urban regions in China and were at the high end of the range reported for western countries. The target antibiotics behaved differently depending on the treatment level employed at the STPs and relatively higher removal efficiencies (>70%) were observed for cefalexin, cefotaxime, amoxicillin, sulfamethoxazole and chloramphenicol during secondary treatment. ß-lactams were especially susceptible to removal via the activated sludge process while macrolides were recalcitrant (<20%) in the dissolved phase. Two fluoroquinolones, ofloxacin (4%) and norfloxacin (52%), differed greatly in their removal efficiencies, probably because of disparities in their pK(a) values which resulted in different sorption behaviour in sludge. Overall antibiotic consumption in Hong Kong was back-calculated based on influent mass flows and compared with available prescription and usage data. This model was verified by a good approximation of 82% and 141% to the predicted consumption of total ofloxacin, but a less accurate estimate was obtained for erythromycin usage. Risk assessment indicated that algae are susceptible to the environmental concentrations of amoxicillin as well as the mixture of the nine detected antibiotics in receiving surface waters.


Assuntos
Antibacterianos/análise , Eliminação de Resíduos Líquidos/estatística & dados numéricos , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos , Amoxicilina/análise , Cefalexina/análise , China , Cloranfenicol/análise , Uso de Medicamentos/estatística & dados numéricos , Monitoramento Ambiental , Eritromicina/análise , Fluoroquinolonas/análise , Hong Kong , Humanos , Macrolídeos/análise , Ofloxacino/análise , Medição de Risco , Esgotos/química , beta-Lactamas/análise
3.
Diabetologia ; 52(2): 235-9, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19030842

RESUMO

AIMS/HYPOTHESIS: The aim of this prospective study was to determine whether circulating intercellular adhesion molecule (ICAM) 1, as a potential surrogate of 'endothelial activation', is more strongly associated with risk of vascular events than with incident diabetes. METHODS: We related baseline ICAM-1 levels to vascular events (866 CHD and stroke events in 5,685 participants) and incident diabetes (292 in 4,945 without baseline diabetes) in the elderly over 3.2 years of follow-up. RESULTS: ICAM-1 levels correlated positively with triacylglycerol but negatively with LDL- and HDL-cholesterol. ICAM-1 levels were higher in those who developed diabetes (388.6 +/- 1.42 vs 369.4 +/- 1.39 ng/ml [mean+/-SD], p = 0.011) and remained independently associated with new-onset diabetes (HR 1.84, 95% CI 1.26-2.69, p = 0.0015 per unit increase in log[ICAM-1] after adjusting for classical risk factors and C-reactive protein). By contrast, ICAM-1 levels were not significantly (p = 0.40) elevated in those who had an incident vascular event compared with those who remained event-free, and corresponding adjusted risk associations were null (HR 0.98, 95% CI 0.80-1.22, p = 0.89) in analyses adjusted for other risk factors. CONCLUSIONS/INTERPRETATION: We show that elevated ICAM-1 levels are associated with risk of incident diabetes in the elderly at risk, despite no association with incident cardiovascular disease risk. We suggest that perturbations in circulating ICAM-1 levels are aligned more towards diabetes risk.


Assuntos
Diabetes Mellitus/epidemiologia , Endotélio Vascular/fisiologia , Molécula 1 de Adesão Intercelular/sangue , Infarto do Miocárdio/epidemiologia , Acidente Vascular Cerebral/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Pressão Sanguínea , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus/sangue , Feminino , Seguimentos , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Incidência , Masculino , Infarto do Miocárdio/sangue , Infarto do Miocárdio/mortalidade , Pravastatina/uso terapêutico , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Acidente Vascular Cerebral/sangue , Acidente Vascular Cerebral/mortalidade , Fatores de Tempo
4.
Exp Gerontol ; 43(8): 801-5, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18504081

RESUMO

Inflammation plays a prominent role in the development of atherosclerosis, which is the most important risk factor for vascular events. Lymphotoxin-alpha (LTA) is a pro-inflammatory cytokine and is found to be expressed in atherosclerotic lesions. We investigated the association between the C804A polymorphism within the LTA gene and coronary and cerebrovascular events in 5804 participants of the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER). The primary endpoint was the combined endpoint of death from coronary heart disease, non-fatal myocardial infarction, and clinical stroke. Secondary endpoints were the coronary and cerebrovascular components separately. All associations were assessed with a Cox-proportional hazards model adjusted for sex, age, pravastatin use, and country. Our overall analysis showed a significant association between the C804A polymorphism and the primary endpoint (p = 0.03). After stratification for gender, this association was found only in males. Furthermore, we found that the association between the C804A polymorphism and the primary endpoint was mainly attributable to clinical strokes (p = 0.02). The C804A polymorphism in the LTA gene associates with clinical stroke, especially in men. But further research is warranted to confirm our results.


Assuntos
Linfotoxina-alfa/genética , Polimorfismo de Nucleotídeo Único , Acidente Vascular Cerebral/genética , Idoso , Idoso de 80 Anos ou mais , Doença das Coronárias/genética , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Heterozigoto , Humanos , Masculino , Infarto do Miocárdio/genética , Fatores de Risco , Fatores Sexuais
5.
Mar Pollut Bull ; 57(6-12): 373-80, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18384818

RESUMO

Six polycyclic musk compounds [Cashmeran (DPMI), Celestolide (ADBI), Phantolide (AHMI), Traseolide (ATII), Tonalide (AHTN), and Galaxolide (HHCB)] were analysed in marine green-lipped mussels (Perna viridis) from Hong Kong. ADBI, HHCB and AHTN were detected in almost all samples, while AHMI, ATII and DPMI were not detected. Concentrations of ADBI, HHCB and AHTN in mussels ranged from below detection limit-0.0743 (mean: 0.0246), 0.247-6.08 (mean: 1.15) and 0.0591-0.738 (mean: 0.190)mg/kg lipid weight, respectively. Mussels from two sampling sites in central Victoria Harbour contained the highest total polycyclic musk levels, suggesting that these waters are heavily influenced by domestic sewage. Concentrations of HHCB and AHTN detected in the mussel samples were the second highest and the highest levels, respectively, compared to global concentrations. A preliminary risk assessment indicated that HHCB and AHTN in mussels pose little or no threat to the health of shellfish consumers. Nevertheless, more comprehensive studies are required to further assess the ecological and human health risks associated with polycyclic musks.


Assuntos
Benzopiranos/metabolismo , Perna (Organismo)/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Animais , Geografia , Hong Kong , Humanos , Medição de Risco , Esgotos/química
6.
Brain ; 131(Pt 4): 1069-77, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18304957

RESUMO

Inflammation is thought to play an important role in the development of cognitive decline and dementia in old age. The interleukin-1 signalling pathway may play a prominent role in this process. The gene encoding for interleukin-1 beta-converting enzyme (ICE) is likely to influence IL-1 beta levels. Inhibition of ICE decreases the age-related increase in IL-1 beta levels and may therefore improve memory function. We assessed whether genetic variation in the ICE gene associates with cognitive function in an elderly population. All 5804 participants of the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) were genotyped for the 10643GC, 9323GA, 8996AG and 5352GA polymorphisms in the ICE gene. Cross-sectional associations between the polymorphisms and cognitive function were assessed with linear regression. Longitudinal associations between polymorphisms, haplotypes and cognitive function were assessed with linear mixed models. All associations were adjusted for sex, age, education, country, treatment with pravastatin and version of test where appropriate. Subjects carrying the variants 10643C and 5352A allele had significantly lower IL-1 beta production levels (P < 0.01). Furthermore, we demonstrated that homozygous carriers of the 10643C and the 5352A allele performed better on all executive function tests at baseline and during follow-up compared to homozygous carriers of the wild-type allele (all P < 0.02). The haplotype with two variants present (10643C and 5352A) was associated with better executive function (all P < 0.02) compared to the reference haplotype without variants. For memory function the same trend was observed, although not significant. Genetic variation in the ICE gene is associated with better performance on cognitive function and lower IL-1 beta production levels. This suggests that low levels of IL-1 beta are protective for memory and learning deficits. Inhibition of ICE may therefore be an important therapeutic target for maintaining cognitive function in old age.


Assuntos
Envelhecimento/genética , Caspase 1/genética , Cognição , Polimorfismo de Nucleotídeo Único , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Caspase 1/fisiologia , Estudos Transversais , Feminino , Genótipo , Haplótipos , Humanos , Interleucina-1beta/biossíntese , Desequilíbrio de Ligação , Estudos Longitudinais , Masculino , Memória , Testes Neuropsicológicos
7.
Chemosphere ; 71(7): 1241-50, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18267326

RESUMO

Synthetic polycyclic musks [Cashmeran (DPMI), Celestolide (ADBI), Phantolide (AHMI), Traseolide (ATII), Tonalide (AHTN), and Galaxolide (HHCB)] were determined in dewatered sludge samples from 10 major sewage treatment plants in Hong Kong using primary treatment (PT), secondary treatment (SecT) or chemical-enhanced primary treatment (CEPT) methods. The concentrations of HHCB, AHTN, AHMI and ADBI ranged from below detection limits to 78.6mg/kg dry weight. HHCB and AHTN were the two predominant polycyclic musks in sludge samples, suggesting the extensive use of these two polycyclic musks in Hong Kong. Polycyclic musk levels in CEPT sludge were significantly higher than those in SecT and PT sludge, suggesting that CEPT sludge has a higher ability to retain polycyclic musks. Comparisons to global concentrations revealed that HHCB and AHTN concentrations detected in Hong Kong sludge ranked first and second respectively. However, the estimated levels of HHCB and AHTN in the discharged effluent from sewage treatment plants may pose low potential risks to aquatic organisms according to the threshold effect levels derived for fish. Nevertheless, the polycyclic musks released in sewage treatment plant effluents may bioconcentrate and bioaccumulate in the marine environment in Hong Kong. Therefore, monitoring studies in marine ecosystems, particularly on the two prevailing polycyclic musks, are necessary.


Assuntos
Perfumes/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Esgotos/análise , Poluentes Químicos da Água/análise , Purificação da Água , Cromatografia Gasosa-Espectrometria de Massas , Hong Kong , Controle de Qualidade , Esgotos/química , Purificação da Água/normas
9.
Ann N Y Acad Sci ; 1100: 189-98, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17460178

RESUMO

Proinflammatory cytokines, like interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha), are implicated in the development of atherosclerosis. The role of anti-inflammatory cytokines, like IL-10, is largely unknown. We investigated the association of four single nucleotide polymorphisms (SNPs) in the promoter region of the IL-10 gene (4259AG, -1082GA, -592CA, and -2849GA), with coronary and cerebrovascular disease in participants of the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER) trial. All associations were assessed with Cox proportional hazards models adjusted for sex, age, pravastatin use, and country. Haplotype analysis of the four SNPs showed a significant association between haplotype 4 (containing the -592A variant allele) and risk of coronary events (P = 0.019). Moreover, analysis of separate SNPs found a significant association between -2849AA carriers with incident stroke (HR (95%CI) 1.50 (1.04-2.17), P value = 0.02). Our study suggests that not only proinflammatory processes contribute to atherosclerosis, but that also anti-inflammatory cytokines may play an important role.


Assuntos
Transtornos Cerebrovasculares/genética , Variação Genética , Interleucina-10/genética , Regiões Promotoras Genéticas , Idoso , Feminino , Haplótipos , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Polimorfismo de Nucleotídeo Único , Pravastatina/farmacologia , Risco , Fatores de Risco
10.
Arch Environ Contam Toxicol ; 51(3): 467-77, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16788744

RESUMO

In vitro studies have demonstrated atrazine-mediated induction of 7-ethoxyresorufin O-deethylase (EROD) activity. EROD is an enzyme active in the metabolism of many compounds, including many xenobiotics. These studies have suggested that atrazine may affect reproductive function by altering steroid metabolism. The goal of this study was to determine whether relationships could be detected between measured atrazine concentrations in surface waters and the liver-somatic index (LSI) and EROD and 7-methoxyresorufin O-deethylase (MROD) activities in the livers of ranid frogs. In addition, sediment dioxin toxic equivalents (TCDD-EQs) were determined using the H4IIE-luc cell bioassay. Adult and juvenile green frogs (Rana clamitans), bullfrogs (R. catesbeiana), and Northern leopard frogs (R. pipiens) were collected from areas with extensive corn cultivation and areas where there was little agricultural activity in south central Michigan in the summer of 2003. Atrazine concentrations at nonagricultural sites ranged from less than the limit of quantification (0.17 microg atrazine/L) to 0.23 microg atrazine/L and did not exceed 1.2 microg atrazine/L at agricultural sites. Sediment TCDD-EQs were measurable only at one agricultural site. Of the measured parameters, only LSI values in adult male frogs differed significantly between agricultural and nonagricultural sites, with greater values observed at agricultural sites. In green frogs, EROD and MROD activities were measurable in both adult and juvenile frogs and were similar among sites. Median EROD activities ranged from 13 to 21 pmol/min/mg protein in adult male green frogs and from 5 to 13 pmol/min/mg protein in adult female green frogs. Juvenile frogs had greater EROD and MROD activities than adult frogs. Bullfrogs and leopard frogs had greater activities than did green frogs. Atrazine concentrations were significantly and negatively correlated with MROD activity in adult male green frogs (Spearman R = -0.800). LSI and EROD and MROD activities of adult female or juvenile green frogs were not significantly correlated with atrazine concentrations. These results suggest that atrazine does not appear to have a consistent association with EROD or MROD activities in wild-caught green frogs.


Assuntos
Agricultura , Citocromo P-450 CYP1A1/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Sedimentos Geológicos/química , Oxirredutases/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Monitoramento Ambiental , Feminino , Masculino , Michigan , Ranidae
11.
Aquat Toxicol ; 77(2): 153-66, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16427146

RESUMO

The triazine herbicide atrazine has been hypothesized to disrupt sexual development in frogs by up-regulating aromatase activity, resulting in greater estradiol (E2) concentrations and causing feminization in males. The goal of this study was to collect native ranid frogs from atrazine-exposed ponds and determine whether relationships exist between measured atrazine concentrations and the gonadosomatic index (GSI), plasma concentrations of testosterone (T), E2 or 11-ketotestosterone (KT), or with aromatase activity. In the summer of 2002 and 2003, adult and juvenile green frogs (Rana clamitans), bullfrogs (R. catesbeiana) and Northern leopard frogs (R. pipiens) were collected from areas with extensive corn cultivation and areas where there was little agricultural activity in south-central Michigan. Atrazine concentrations were below the limit of quantification at non-agricultural sites. Atrazine concentrations did not exceed 2 microg/L at most agricultural sites, but a concentration of 250 microg atrazine/L was measured in one sample from one site in 2002. Plasma steroid concentrations varied among locations. Aromatase activity was measurable in less than 11% of testes in adult males, and in less than 4% of testes in juvenile males. Median aromatase activities in ovaries of adult females ranged from 3 to 245 pmol/h/mg protein, and maximum activities were 2.5-fold greater in juveniles than in adults. Atrazine concentrations were not significantly correlated with any of the parameters measured in this study. These results indicate that atrazine does not up-regulate aromatase in green frogs in the wild, and does not appear to affect plasma steroid hormone concentrations.


Assuntos
Aromatase/metabolismo , Atrazina/toxicidade , Exposição Ambiental , Herbicidas/toxicidade , Ranidae/fisiologia , Animais , Aromatase/efeitos dos fármacos , Estradiol/sangue , Feminino , Água Doce , Gônadas/enzimologia , Masculino , Michigan , Estações do Ano , Fatores Sexuais , Testosterona/análogos & derivados , Testosterona/sangue , Poluição Química da Água/efeitos adversos
12.
Aquat Toxicol ; 76(3-4): 230-45, 2006 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-16300839

RESUMO

The triazine herbicide atrazine has been suggested to be a potential disruptor of normal sexual development in male frogs. The goals of this study were to collect native ranid frogs from sites in agricultural and non-agricultural areas and determine whether hypothesised atrazine effects on the gonads could be observed at the gross morphological and histological levels. Juvenile and adult green frogs (Rana clamitans), bullfrogs (R. catesbeiana) and leopard frogs (R. pipiens) were collected in the summers of 2002 and 2003. Atrazine concentrations were below the limit of quantification at non-agricultural sites, and concentrations did not exceed 2 microg/L at most agricultural sites. One concentration greater than 200 microg atrazine/L was measured once at one site in 2002. Hermaphroditic individuals with both male and female gonad tissue in either one or both gonads, were found at a low incidence at both non-agricultural and agricultural sites, and in both adults and juveniles. Testicular oocytes (TO) were found in male frogs at most of the sites, with the greatest incidence occurring in juvenile leopard frogs. TO incidence was not significantly different between agricultural and non-agricultural sites with the exception of juveniles collected in 2003. Atrazine concentrations were not significantly correlated with the incidence of hermaphroditism, but maximum atrazine concentrations were correlated with TO incidence in juvenile frogs in 2003. However, given the lack of a consistent relationship between atrazine concentrations and TO incidence, it is more likely the TOs observed in this study result from natural processes in development rather than atrazine exposure.


Assuntos
Agroquímicos/toxicidade , Atrazina/toxicidade , Transtornos do Desenvolvimento Sexual/veterinária , Herbicidas/toxicidade , Ranidae , Agroquímicos/análise , Animais , Atrazina/análise , Transtornos do Desenvolvimento Sexual/induzido quimicamente , Transtornos do Desenvolvimento Sexual/epidemiologia , Feminino , Gônadas/anatomia & histologia , Gônadas/efeitos dos fármacos , Gônadas/patologia , Gônadas/ultraestrutura , Herbicidas/análise , Incidência , Deformidades Congênitas dos Membros/induzido quimicamente , Deformidades Congênitas dos Membros/epidemiologia , Deformidades Congênitas dos Membros/veterinária , Masculino , Michigan , Ranidae/anatomia & histologia , Ranidae/fisiologia , Fatores de Tempo , Água/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
13.
J Neurol Neurosurg Psychiatry ; 73(4): 385-9, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12235304

RESUMO

OBJECTIVES: For large scale follow up studies with non-demented patients in which cognition is an endpoint, there is a need for short, inexpensive, sensitive, and reliable neuropsychological tests that are suitable for repeated measurements. The commonly used Mini-Mental-State-Examination fulfils only the first two requirements. METHODS: In the PROspective Study of Pravastatin in the Elderly at Risk (PROSPER), 5804 elderly subjects aged 70 to 82 years were examined using a learning test (memory), a coding test (general speed), and a short version of the Stroop test (attention). Data presented here were collected at dual baseline, before randomisation for active treatment. RESULTS: The tests proved to be reliable (with test/retest reliabilities ranging from acceptable (r=0.63) to high (r=0.88) and sensitive to detect small differences in subjects from different age categories. All tests showed significant practice effects: performance increased from the first measurement to the first follow up after two weeks. CONCLUSION: Normative data are provided that can be used for one time neuropsychological testing as well as for assessing individual and group change. Methods for analysing cognitive change are proposed.


Assuntos
Anticolesterolemiantes/uso terapêutico , Transtornos Cognitivos/diagnóstico , Hipercolesterolemia/tratamento farmacológico , Testes Neuropsicológicos , Pravastatina/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Testes Neuropsicológicos/normas , Estudos Prospectivos , Reprodutibilidade dos Testes
14.
J Biol Chem ; 276(41): 38242-8, 2001 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-11477099

RESUMO

DNA double-strand breaks (DSBs) are a highly mutagenic and potentially lethal damage that occurs in all organisms. Mammalian cells repair DSBs by homologous recombination and non-homologous end joining, the latter requiring DNA-dependent protein kinase (DNA-PK). Werner syndrome is a disorder characterized by genomic instability, aging pathologies and defective WRN, a RecQ-like helicase with exonuclease activity. We show that WRN interacts directly with the catalytic subunit of DNA-PK (DNA-PK(CS)), which inhibits both the helicase and exonuclease activities of WRN. In addition we show that WRN forms a stable complex on DNA with DNA-PK(CS) and the DNA binding subunit Ku. This assembly reverses WRN enzymatic inhibition. Finally, we show that WRN is phosphorylated in vitro by DNA-PK and requires DNA-PK for phosphorylation in vivo, and that cells deficient in WRN are mildly sensitive to ionizing radiation. These data suggest that DNA-PK and WRN may function together in DNA metabolism and implicate WRN function in non-homologous end joining.


Assuntos
DNA Helicases/metabolismo , Proteínas de Ligação a DNA , Proteínas Serina-Treonina Quinases/metabolismo , Síndrome de Werner/metabolismo , Androstadienos/farmacologia , Sequência de Bases , Primers do DNA , Proteína Quinase Ativada por DNA , Inibidores Enzimáticos/farmacologia , Exodesoxirribonucleases , Fosforilação , Ligação Proteica , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , RecQ Helicases , Helicase da Síndrome de Werner , Wortmanina
19.
Am J Hypertens ; 13(10): 1067-73, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11041160

RESUMO

The aim of this study was to assess the contribution of physical activity levels to blood pressure (BP) variability, and to assess the effect age, gender, body mass index, and use of antihypertensive medications on this relationship. We simultaneously monitored 24-h ambulatory BP by automated recorder and activity by actigraphy in 431 patients. Mean activity scores for the 5, 10, 15, and 20 min preceding each BP measurement were calculated, and BP and heart rate were related to these variables using linear mixed model regression. Various patient characteristics were added to the mixed model as covariates. Patients were heterogeneous in age (48 +/- 13 years), sex (49% men), and average 24-h BP (132/81 +/- 15/10 mm Hg). Mean daytime activity level was 44 +/- 15 U. During the daytime, systolic BP (r = 0.33), diastolic BP (r = 0.29), and heart rate (r = 0.42) correlated best with the average activity for the 15 min preceding each measurement (P < .001). Variance was very high, with activity explaining from 0% to 62% of BP variability for different individuals. Men and the obese had a greater reactivity of systolic BP to activity; older patients and those on antihypertensive therapy had a lower reactivity of heart rate. Blood pressure level is significantly associated with physical activity, but the percentage of variance of BP explained by physical activity varies greatly between individuals. Correlation is strongest between BP and average activity integrated over the previous 15 min. Much of the variance in blood pressure remains unexplained.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Anti-Hipertensivos/uso terapêutico , Diástole , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/fisiopatologia , Caracteres Sexuais , Sístole
20.
Am J Hypertens ; 13(6 Pt 1): 601-6, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10912741

RESUMO

This study was designed to describe the interaction between physical activity (PA), quantified objectively by electronic activity monitors, and ambulatory blood pressure (ABP), and to test the hypothesis that modifying daily PA can effect significant changes in the diurnal variation in blood pressure and may result in altered dipping/nondipping status of an individual. Initially, 70 individuals underwent simultaneous ABP and electronic activity monitoring (actigraph devices manufactured by Gaewihler Electronics, Switzerland) over a 24-h period. Then, in a prospective study, the dipping/nondipping status of 43 subjects was assessed using ABP recorded over two 24-h periods of differing activity levels. Of the 70 subjects (age 49 +/- 11 years, 42 male) the diurnal variation in systolic blood pressure (20 +/- 12%, step-up from night [120 +/- 12 mm Hg] to day [144 +/- 13 mm Hg]) and diurnal variation in PA score (increment from sleep, 44 +/- 17 units) correlated significantly (R2 = 0.29; P < .05). Of the 43 subjects who underwent ABP monitoring on a more active day, four had a nondipping BP profile; 12 of these same 43 subjects had a nondipping BP profile when monitored on a less active day (chi2 = 4.9; P < .05). These results provide a quantitative description of the contribution of PA, including the sleep/awake status, to blood pressure variation in a group of normotensive and hypertensive individuals. The magnitude of this effect underscores the importance of interpreting 24-h ABP data only in the presence of adequately quantified activity data.


Assuntos
Pressão Sanguínea/fisiologia , Ritmo Circadiano/fisiologia , Aptidão Física/fisiologia , Adulto , Monitorização Ambulatorial da Pressão Arterial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
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