RESUMO
World Health Organization (WHO), in cooperation with the Consortium to Perform Human Biomonitoring on a European Scale (COPHES), has developed a standardized methodology for human biomonitoring (HBM) surveys in maternities in order to assess prenatal exposure to mercury. To test this standard methodology and adapt it to Russian settings, a cross-sectional HBM survey involving 120 parturient women was conducted in six maternities of the Moscow Region. Levels of total mercury in maternal hair (geometric mean: 0.21 µg/g, 95th percentile: 0.54 µg/g), cord blood (0.89 µg/L and 2.38 µg/L, respectively) and maternal urine (0.27 µg/L and 0.94 µg/L) in this population were similar to those in other European countries with relatively low fish consumption. Consumption of all types of fish at least once per week during the third trimester of pregnancy compared to fish consumption less than once per month was associated with the increase of geometric mean level of total mercury: in hair by 31% (95% confidence interval: 4%, 66%) higher, in cord blood--by 38% (9%, 74%) and in maternal urine--by 36% (2%, 81%). No biomarker values exceeded levels recommended by WHO or national agencies in the USA and Germany. However; at the population level, adverse effects of prenatal exposures to mercury can still be substantial.
Assuntos
Monitoramento Ambiental , Exposição Materna , Mercúrio/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Comportamento Alimentar , Feminino , Sangue Fetal/química , Cabelo/química , Humanos , Exposição Materna/efeitos adversos , Mercúrio/sangue , Mercúrio/farmacocinética , Mercúrio/urina , Gravidez , Terceiro Trimestre da Gravidez , Federação Russa , Alimentos Marinhos , Inquéritos e Questionários , Poluentes Químicos da Água/sangue , Poluentes Químicos da Água/farmacocinética , Poluentes Químicos da Água/urina , Organização Mundial da SaúdeRESUMO
BACKGROUND: Serological data suggest that Cryptosporidium infections are common but underreported. The invasiveness of blood sampling limits the application of serology in epidemiological surveillance. We pilot-tested a non-invasive salivary anti-Cryptosporidium antibody assay in a community survey involving children and adults. MATERIALS AND METHODS: Families with children were recruited in a Massachusetts community in July; symptoms data were collected at 3 monthly follow-up mail surveys. One saliva sample per person (n = 349) was collected via mail, with the last survey in October. Samples were analyzed for IgG and IgA responses to a recombinant C. hominis gp15 sporozoite protein using a time-resolved fluorometric immunoassay. Log-transformed assay results were regressed on age using penalized B-splines to account for the strong age-dependence of antibody reactions. Positive responses were defined as fluorescence values above the upper 99% prediction limit. RESULTS: Forty-seven (13.5%) individuals had diarrhea without concurrent respiratory symptoms during the 3-month-long follow-up; eight of them had these symptoms during the month prior to saliva sampling. Two individuals had positive IgG responses: an adult who had diarrhea during the prior month and a child who had episodes of diarrhea during each survey month (Fisher's exact test for an association between diarrhea and IgG response: p = 0.0005 for symptoms during the prior month and p = 0.02 for symptoms during the entire follow-up period). The child also had a positive IgA response, along with two asymptomatic individuals (an association between diarrhea and IgA was not significant). CONCLUSION: These results suggest that the salivary IgG specific to Cryptosporidium antigens warrants further evaluation as a potential indicator of recent infections.
Assuntos
Anticorpos Antiprotozoários/análise , Cryptosporidium/imunologia , Diarreia/etiologia , Imunoglobulina G/análise , Saliva/imunologia , Adolescente , Adulto , Animais , Antígenos de Protozoários , Criança , Pré-Escolar , Feminino , Humanos , Imunoensaio/métodos , Imunoglobulina A/análise , Lactente , Masculino , Massachusetts , Pessoa de Meia-Idade , Adulto JovemRESUMO
The previously unknown absolute intensities of 28 prompt gamma-rays from the thermal neutron capture in 91Zr, 143Nd, 177Hf and 116,118-120,122,124Sn were measured by an in-beam gamma-spectroscopy method at the WWR-M reactor (PNPI, Gatchina). Cross sections of the production of isomers 123m,125mSn were also measured.
Assuntos
Raios gama , Espectrometria gama/métodos , Háfnio/análise , Neodímio/análise , Estanho/análise , Zircônio/análiseRESUMO
Bioflavonoids (polyhydroxyphenols) are ubiquitous components of plants, fruits and vegetables; these compounds are efficient scavengers of free oxygen radicals and peroxides. The aim of this study was to investigate the antioxidative effects of genistein-8-C-glycoside (G8CG) isolated from the flowers of Lipinus luteus L. G8CG dose-dependently inhibited membrane lipid peroxidation and prevented GSH oxidation in human red blood cells and rat liver homogenates under tert-butylhydroperoxide-induced oxidative stress and single whole-body gamma-irradiation (1 Gy) of rats.
Assuntos
Antioxidantes/farmacologia , Eritrócitos/efeitos dos fármacos , Raios gama , Genisteína/análogos & derivados , Glucosídeos/farmacologia , Fígado/efeitos dos fármacos , Estresse Oxidativo , Animais , Antioxidantes/isolamento & purificação , Células Cultivadas , Relação Dose-Resposta a Droga , Eritrócitos/metabolismo , Genisteína/isolamento & purificação , Genisteína/farmacologia , Glucosídeos/isolamento & purificação , Humanos , Fígado/metabolismo , Fígado/efeitos da radiação , Lupinus/química , Masculino , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Ratos , Irradiação Corporal TotalRESUMO
Alimentary obesity induced by the long-term feeding of rats by high-fat diet results the reducing of rate and efficiency of oxidative phosphorylation in liver mitochondria when NAD-dependent substrates are used. The treatment of the obese rats with panthotenic acid derivatives (phosphopantotenate, panthetin, panthenol) enhanced oxidative phosphorylation of pyruvate and fatty acid carnitine esters. Among investigated compounds panthenol activated respiratory control and phosphorylation rate more effectively. Moreover, panthenol, but not phosphopanthotenate nor panthetine, increased the activity of carnitine palmitoyltransferase 1 that confirms the preferable usage of fatty acids for mitochondrial oxidation under the influence of this compound.
Assuntos
Mitocôndrias Hepáticas/metabolismo , Obesidade/metabolismo , Fosforilação Oxidativa/efeitos dos fármacos , Ácido Pantotênico/administração & dosagem , Animais , Carnitina/metabolismo , Carnitina O-Palmitoiltransferase/metabolismo , Ácidos Graxos/metabolismo , Feminino , Obesidade/patologia , Oxirredução , Ácido Pantotênico/análogos & derivados , Ácido Pirúvico/metabolismo , RatosRESUMO
The present study was performed to determine how sympathetic function is altered by simulated microgravity, dry immersion for 3 days, and to elucidate the mechanism of post-spaceflight orthostatic intolerance in humans. Six healthy men aged 21-36 years old participated in the study. Before and after the dry immersion, subjects performed head-up tilt (HUT) test to 30 degrees and 60 degrees (5 min each) with recordings of muscle sympathetic nerve activity (MSNA, by microneurography), electrocardiogram, and arterial blood pressure (Finapres). Resting MSNA was increased after dry immersion from 23.7+/-3.2 to 40.9+/-3.0 bursts/min (p<0.005) without significant changes in resting heart rate (HR). MSNA responsiveness to orthostasis showed no significant difference but HR response was significantly augmented after dry immersion (p<0. 005). A significant diastolic blood pressure fall at 5th min of 60 degrees HUT was observed in five orthostatic tolerant subjects despite enough MSNA discharge after dry immersion. A subject suffered from presyncope at 2 min after 60 degrees HUT. He showed gradual blood pressure fall 10 s after 60 degrees HUT with initially well-maintained MSNA response and then with a gradually attenuated MSNA, followed by a sudden MSNA withdrawal and abrupt blood pressure drop. In conclusion, dry immersion increased MSNA without changing MSNA response to orthostasis, and resting HR, while increasing the HR response to orthostasis. Analyses of MSNA and blood pressure changes in orthostatic tolerant subjects and a subject with presyncope suggested that not only insufficient vasoconstriction to sympathetic stimuli, but also a central mechanism to induce a sympathetic withdrawal might play a role in the development of orthostatic intolerance after microgravity exposure.