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2.
Sci Rep ; 11(1): 6199, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33739021

RESUMEN

Elevated levels of radon and thoron in the indoor atmosphere may cause the deleterious effects on the mankind. Mining sites and their environs attract a special interest in radon studies as higher levels are frequently reported in the habitats. In the present study, radon and thoron levels were measured in the dwellings of Buddonithanda, a village in the environs of proposed uranium mining site, with pin-hole (SSNTDs) dosimeters for the period of a year. The measured radon and thoron levels were found to vary widely from 14 to 675 Bq m-3 (geometric mean = 94 Bq m-3) and from 21 to 704 Bq m-3 (geometric mean = 121 Bq m-3), respectively. An attempt was made to understand the large spatial variation of these levels. The seasonal and diurnal variation studies were used in unraveling the behavior of the radioactive isotopes in indoor environment and the same was explained with the help of a simplified mathematical model. Quantification of inhalation dose due to radon and thoron was done with suitable occupancy factors.

3.
Food Funct ; 7(3): 1574-83, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26902315

RESUMEN

The formation of advanced glycation end products (AGEs) is a characteristic feature of diabetic tissues and accumulation of these products has been implicated in the pathogenesis of micro- and macrovascular complications of diabetes including diabetic nephropathy (DN). Compelling evidence suggests that AGEs mediate progressive alteration in the renal architecture and loss of renal function whereas inhibitors of AGEs prevent the progression of experimental DN. We have investigated the potential of ellagic acid (EA), a polyphenol present abundantly in fruits and vegetables, to prevent in vivo accumulation of AGE and to ameliorate renal changes in diabetic rats. Streptozotocin-induced diabetic rats were fed with either 0.2% or 2% of EA in the diet for 12 weeks. Dietary supplementation of EA to diabetic rats prevented the glycation mediated RBC-IgG-cross-links and HbA1c accumulation. EA inhibited the accumulation of N-carboxymethyl lysine (CML), a predominant AGE in the diabetic kidney. Further, EA also prevented the AGE-mediated loss of expression of podocyte slit diaphragm proteins: nephrin and podocin. By inhibiting CML formation, EA improved renal function in rats as evidenced by urinary albumin and creatinine levels. In conclusion, EA inhibited AGE accumulation in the diabetic rat kidney and ameliorated AGE-mediated pathogenesis of DN.


Asunto(s)
Nefropatías Diabéticas/prevención & control , Ácido Elágico/administración & dosificación , Productos Finales de Glicación Avanzada/metabolismo , Proteinuria/prevención & control , Animales , Glucemia/metabolismo , Nefropatías Diabéticas/metabolismo , Glicosilación/efectos de los fármacos , Humanos , Riñón/efectos de los fármacos , Riñón/metabolismo , Masculino , Proteinuria/metabolismo , Ratas , Ratas Wistar
4.
Radiat Prot Dosimetry ; 151(2): 290-8, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22319131

RESUMEN

The present work was aimed at the establishment of baseline radioactive data in the proposed Lambapur and Peddagattu uranium mining areas in the Andhra Pradesh state, India. The background concentrations of naturally occurring radioactivity in the near-surface soils of the study areas were estimated and the results were analysed. The (238)U concentration in the near-surface soil of the study area was found to vary from 100 to 176 Bq kg(-1), with a mean of 138±24 Bq kg(-1). (232)Th in the study area soils was found to vary between 64 and 116 Bq kg(-1), with a mean of 83±15 Bq kg(-1). The (40)K concentration was found to vary between 309 and 373 Bq kg(-1), with a mean of 343±20 Bq kg(-1). The mean natural background radiation levels were also measured with thermoluminescence (TL) dosimetry technique and with a µR-survey meter, in the villages of the study area. Dose rates measured by TL are found to vary from 1287 to 3363 µGy y(-1), with a mean of 2509 ± 424 µGy y(-1). The dose rates measured in the same villages with a µR-survey meter were found to be in the range of 1211-3255 µGy y(-1), with a mean of 2524 ± 395 µGy y(-1). The mean radiation levels in the study area are found to be relatively high when compared with (Indian) national and international averages. Correlations among radon, thoron and gamma dose rates were found to be poor. The pre-operational data produced in this work will be useful for comparison with future radiation levels during the proposed uranium mining operations.


Asunto(s)
Radiación de Fondo , Minería , Monitoreo de Radiación , Contaminantes Radiactivos del Suelo/análisis , Uranio/análisis , Rayos gamma , Humanos , India , Dosis de Radiación , Radón/análisis , Torio/análisis
5.
Radiat Prot Dosimetry ; 132(4): 403-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-19122001

RESUMEN

Indoor radon levels in urban areas of Hyderabad, Andhra Pradesh, India were measured by a time integrated method using solid state nuclear track detector-based dosemeters. Results show that the radon levels varied widely in the area ranging from 17 to 311 Bq m(-3) with a geometric mean value of 52.8 Bq m(-3) (GSD=1.7). Cumulative frequency distribution of radon levels gave a best fit on a log-normal scale. Measurements were carried out for 1 y, segregating the measurement periods in accordance with seasonal changes. Soil samples from the region were also analysed for natural radionuclides to study its effect, if any, on indoor radon levels. Dwellings categorised based on construction types showed that the average radon levels in the order tiles (TLE)>asbestos (ASB)>concrete (RCC) for the roof structures. The estimated radon levels in the study area are relatively higher than the country's average value of 23 Bq m(-3) and global average value of 30 Bq m(-3).


Asunto(s)
Contaminantes Radiactivos del Aire/análisis , Contaminación del Aire Interior/análisis , Radón/análisis , Contaminantes Radiactivos del Suelo/análisis , Calibración , Materiales de Construcción , Vivienda , Humanos , India , Monitoreo de Radiación , Estaciones del Año , Población Urbana
6.
J Environ Radioact ; 73(1): 21-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15001293

RESUMEN

Thoron and its progeny concentration levels were measured in the urban Hyderabad area using solid state nuclear track detector (SSNTD) based dosimeters. Measurements were carried out on quarterly cycles making four measurements at each location in a calendar year. More than 100 dwellings of different construction types were chosen for the study across Hyderabad city. The thoron concentration levels were found to vary between 8 and 330 Bq m(-3). The geometric mean value of thoron concentration was found to be 37.3 Bq m(-3) (GSD = 2.3) with an average of 55 +/- 57 Bq m(-3). Results were analysed for different category of houses with respect to their construction type. It was found that the dwellings with mud flooring had higher thoron levels.


Asunto(s)
Contaminación del Aire Interior/análisis , Contaminantes Radiactivos/análisis , Radón/análisis , Monitoreo del Ambiente , Vivienda , India , Valores de Referencia , Población Urbana
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