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1.
Arch Environ Contam Toxicol ; 76(1): 142-152, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30361943

RESUMO

The fate of a pollutant in the environment depends on its interaction with the surroundings. Henry's law constant (HLC) is one of the important properties useful for assessment of environmental risk and estimation of mass transfer of the pollutant between water and air. Estimation of HLC is relatively a difficult task for many of the organic pollutants due to their very low aqueous solubility. People have attempted the measurement of HLC for persistent organic pollutants, such as polychlorinated biphenyls (PCBs), but due to the difficulty in estimation, there is a variation of approximately 2-3 orders of magnitude in reported values of HLC for PCBs in the literature. A study was performed for estimation of HLC for PCBs using the static method with a modification that eliminates any disturbance in equilibrium due to sampling and also avoids removal or addition of material in or out of the system unlike the conventional methods. The results were consistent with the literature values. The experimental values of HLC ranged from 0.004 to 0.08 for different congeners. All of the experimental values were in agreement with the literature values. The experimental data was further used for deriving a correlation equation for theoretical estimation of the HLC from aqueous solubility and chlorination number. The equation gave a very good estimation of HLC values for all the PCBs congeners except single- and double-chlorinated congeners. The theoretically predicted values were also found to be in close agreement with the reported HLC values.


Assuntos
Ar , Poluentes Ambientais/análise , Modelos Teóricos , Bifenilos Policlorados/análise , Água/química , Monitoramento Ambiental , Poluentes Ambientais/química , Halogenação , Bifenilos Policlorados/química , Solubilidade , Volatilização
2.
Anal Chem ; 89(1): 871-876, 2017 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-27936602

RESUMO

Total reflection X-ray fluorescence (TXRF)-based X-ray absorption near-edge spectroscopy has been used to determine the oxidation state of uranium in mixed-valent U3O8 and U3O7 uranium oxides. The TXRF spectra of the compounds were measured using variable X-ray energies in the vicinity of the U L3 edge in the TXRF excitation mode at the microfocus beamline of the Indus-2 synchrotron facility. The TXRF-based X-ray absorption near-edge spectroscopy (TXRF-XANES) spectra were deduced from the emission spectra measured using the energies below and above the U L3 edge in the XANES region. The data processing using TXRF-XANES spectra of U(IV), U(V), and U(VI) standard compounds revealed that U present in U3O8 is a mixture of U(V) and U(VI), whereas U in U3O7 is mixture of U(IV) and U(VI). The results obtained in this study are similar to that reported in literature using the U M edge. The present study has demonstrated the possibility of application of TXRF for the oxidation state determination and elemental speciation of radioactive substances in a nondestructive manner with very small amount of sample requirement.

3.
Pancreatology ; 15(1): 40-5, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25455347

RESUMO

BACKGROUND/OBJECTIVES: Pancreatectomy with autologous islet transplantation has slowly been proving to be an effective way of treating chronic pancreatitis while lessening the effects of the concomitant surgical diabetes of pancreatectomy alone. Assessing patient quality of life and pain after the procedure is particularly important as intractable pain is the main complaint for which patients undergo total pancreatectomy. METHODS: We used the Rand SF-36 and McGill pain questionnaires, and Visual Analogue Scale to assess patients preoperatively for quality of life and pain resulting from life with chronic pancreatitis. After undergoing total pancreatectomy with autologous islet transplantation (TPAIT), patients were followed with surveys administered at 1 month, 6 months, and 1 year to evaluate changes in their quality of life and pain experienced. RESULTS: Significant improvement was reported in all components of every questionnaire within a year after surgery. Furthermore, patient reported mean scores on quality of life were found to fall within the range of the general population. CONCLUSIONS: From our experience with 53 patients at the University of Arizona, after pancreatectomy with autologous islet transplantation patients reported a higher quality of life when compared to preoperative values, as well as reduced levels of pain.


Assuntos
Dor Abdominal/etiologia , Transplante das Ilhotas Pancreáticas , Dor Intratável/etiologia , Dor Pós-Operatória/diagnóstico , Pancreatectomia , Pancreatite Crônica/cirurgia , Qualidade de Vida , Dor Abdominal/diagnóstico , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Dor Intratável/diagnóstico , Pancreatite Crônica/complicações , Período Pré-Operatório , Inquéritos e Questionários , Transplante Autólogo , Resultado do Tratamento
4.
Am J Transplant ; 14(11): 2595-606, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25278159

RESUMO

The Collaborative Islet Transplant Registry (CITR) collects data on clinical islet isolations and transplants. This retrospective report analyzed 1017 islet isolation procedures performed for 537 recipients of allogeneic clinical islet transplantation in 1999-2010. This study describes changes in donor and islet isolation variables by era and factors associated with quantity and quality of final islet products. Donor body weight and BMI increased significantly over the period (p<0.001). Islet yield measures have improved with time including islet equivalent (IEQ)/particle ratio and IEQs infused. The average dose of islets infused significantly increased in the era of 2007-2010 when compared to 1999-2002 (445.4±156.8 vs. 421.3±155.4×0(3) IEQ; p<0.05). Islet purity and total number of ß cells significantly improved over the study period (p<0.01 and <0.05, respectively). Otherwise, the quality of clinical islets has remained consistently very high through this period, and differs substantially from nonclinical islets. In multivariate analysis of all recipient, donor and islet factors, and medical management factors, the only islet product characteristic that correlated with clinical outcomes was total IEQs infused. This analysis shows improvements in both quantity and some quality criteria of clinical islets produced over 1999-2010, and these parallel improvements in clinical outcomes over the same period.


Assuntos
Sobrevivência de Enxerto , Transplante das Ilhotas Pancreáticas , Sistema de Registros , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Chemosphere ; 359: 142354, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38759812

RESUMO

Degradation of ibuprofen, one of the most consumed drugs globally, by a mixed bacterial consortium was investigated. A contaminated hospital soil was used to enrich a bacterial consortium possessing the ability to degrade 4 mg/L ibuprofen in 6 days, fed on 6 mM acetate as a supplementary carbon source. Maximum ibuprofen degradation achieved was 99.51%, and for optimum ibuprofen degradation modelled statistically, the initial ibuprofen concentration, and temperature were determined to be 0.515 mg/L and 35 °C, respectively. The bacterial community analyses demonstrated an enrichment of Pseudomonas, Achromobacter, Bacillus, and Enterococcus in the presence of ibuprofen, suggesting their probable association with the biodegradation process. The biodegradation pathway developed using open-source metabolite predictors, GLORYx and BioTransformer suggested multiple degradation routes. Hydroxylation and oxidation were found to be the major mechanisms in ibuprofen degradation. Mono-hydroxylated metabolites were identified as well as predicted by the bioinformatics-based packages. Oxidation, dehydrogenation, super-hydroxylation, and hydrolysis were some other identified mechanisms.


Assuntos
Biodegradação Ambiental , Ibuprofeno , Consórcios Microbianos , Ibuprofeno/metabolismo , Redes e Vias Metabólicas , Bactérias/metabolismo , Microbiologia do Solo , Oxirredução , Hidroxilação , Pseudomonas/metabolismo , Achromobacter/metabolismo , Poluentes do Solo/metabolismo , Bacillus/metabolismo
6.
J Synchrotron Radiat ; 20(Pt 2): 386-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23412498

RESUMO

A microfocus X-ray fluorescence spectroscopy beamline (BL-16) at the Indian synchrotron radiation facility Indus-2 has been constructed with an experimental emphasis on environmental, archaeological, biomedical and material science applications involving heavy metal speciation and their localization. The beamline offers a combination of different analytical probes, e.g. X-ray fluorescence mapping, X-ray microspectroscopy and total-external-reflection fluorescence characterization. The beamline is installed on a bending-magnet source with a working X-ray energy range of 4-20 keV, enabling it to excite K-edges of all elements from S to Nb and L-edges from Ag to U. The optics of the beamline comprises of a double-crystal monochromator with Si(111) symmetric and asymmetric crystals and a pair of Kirkpatrick-Baez focusing mirrors. This paper describes the performance of the beamline and its capabilities with examples of measured results.


Assuntos
Síncrotrons/instrumentação , Cristalografia por Raios X/métodos , Desenho de Equipamento , Índia , Solanum lycopersicum/química , Folhas de Planta/química , Espectrometria por Raios X/métodos
7.
J Ayurveda Integr Med ; 14(2): 100690, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36822148

RESUMO

In Ayurveda, 'Lauha' (Iron) Bhasma is primarily used to cure diseases related to iron deficiency in humans. It is produced from purified raw metallic iron using a combination of multi-step traditional preparation processes described in the Ayurveda literature. Here, we present the results of structural investigation performed on the medicinal grade 'Lauha' Bhasma using various X-ray based techniques. Our results indicate that after several rounds of heating and cooling in specific conditions following the Ayurvedic preparation procedure, metallic iron eventually converts to a natural iron-oxide mineral belonging to the magnetite group. Scanning electron microscopy (SEM) and X-ray standing wave assisted fluorescence measurements carried out on powdered Bhasma specimen reveal that the magnetite micro-particles in the Bhasma specimen are usually present in the form of agglomerates of nano-particles. We anticipate that the Ayurvedic Lauha Bhasma has great potential for noninvasive localized target killing of cancer cells, particularly in sensitive parts of the human body such as the brain, spinal cord, and lungs, via necrosis by application of an alternating external magnetic field or photo electron generation through X-rays.

8.
Anal Sci ; 39(11): 1889-1899, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37495926

RESUMO

In this work, we describe the development of an electrochemical sensing platform that employs electrochemically reduced graphene oxide (ErGO) and gold (Au) deposited on a screen-printed carbon electrode (SPCE) to synthesize Au/ErGO/SPCE for the determination of the antibiotic drug doxycycline (DC). A modified Hummer's approach was adopted to initially prepare graphene oxide, which was then characterized by using powder XRD, FTIR, and UV spectroscopy before being utilized for modification on SPCE. Cyclic voltammetry was performed to form ErGO on SPCE to give ErGO/SPCE followed by electrodeposition of gold to get a final modified electrode Au/ErGO/SPCE. The effect of experimental conditions, like scan rate and pH on the electrochemical behavior of DC for Au/ErGO/SPCE, was evaluated. Square wave voltammetry (SWV) and cyclic voltammetry (CV) measurements were used to assess the electro-oxidation of DC on Au/ErGO/SPCE, and the electrochemical reaction conditions were also optimized. Furthermore, Au/ErGO/SPCE-based electrochemical sensors showed good recovery and high accuracy for DC determination in the complex food matrix and blood serum. The limit of detection (LOD), the limit of quantification (LOQ), and the linear calibration range of DC on Au/ErGO/SPCE under optimum experimental conditions were 0.124 µm, 0.415 µm, and 1-100 µm respectively, with high sensitivity of 0.194 µA µM-1 cm-2. Finally, the proposed electrochemical sensing platform was effectively used to determine low DC concentrations in real samples such as chicken flesh and blood serum, indicating its wide range of applications in quality control.

9.
Water Environ Res ; 94(7): e10759, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35796043

RESUMO

The pollutants released from pharmaceutical, steel, paper, and battery industries into water cause stress on the natural ecosystems, may mix with soil and water, enter into human food chain, and hence cause irreparable damage to the biotic system. Hence, the appropriate monitoring of water along with determination of heavy metals is very important for human beings. In present paper, total reflection X-ray fluorescence (TXRF) spectrometry technique is employed to determine the level of different contaminants in the water samples gathered from the various sites of an identified industrial area. Experimentation is carried out at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore-India by using TXRF, which is one the advance techniques of element determination up to ppb levels. The elemental concentration of Cl, K, Ca, Fe, Cu, Zn, Ga, Br, Sr, As, Pb, and Ni is quantified and compared with the limits established by the WHO (World Health Organization) and BIS (Bureau of Indian Standard) guidelines regarding drinking water use. The levels of the Pb, Fe, As, Ni, Cr, Co, and Mn exceeded the values suggested by WHO and BIS at some locations/sites. To better understand the situation, water quality parameters such as Water Quality Index (WQI), Heavy metal Pollution Index (HPI), Contamination Index (CI), Metal Enrichment Index (MEI), and Heavy Metal Evaluation Index (HEI) have also been assessed for all the sites close to industrial hub. Among all sites except at A3 and A6, WQI is found to be much greater than WHO and BIS established limit. Level of arsenic in the water at A1 location was found 73 ppb. However, lead metal in water was found to be very high at all the six studied locations, and at A1 location, it is found extremely high 2613 ppb. Therefore, water at A1 and A2 sites is found to be unfit for drinking. PRACTITIONER POINTS: Total reflection X-ray fluorescence (TXRF) spectrometry technique is employed to determine the level of different contaminants in the water samples The elemental concentration of Cl, K, Ca, Fe, Cu, Zn, Ga, Br, Sr, As, Pb, and Ni is quantified and compared with the limits prescribed by the WHO Water Quality Index (WQI), Heavy metal Pollution Index (HPI), Contamination Index (CI), Metal Enrichment Index (MEI), and Heavy Metal Enrichment Index (MEI) have also been assessed for all the sites Water at some sites is found unfit for drinking purpose. Based on the observations, some remedial measures are suggested to reduce the level of water contaminants up to desired levels.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Ecossistema , Monitoramento Ambiental/métodos , Humanos , Chumbo , Metais Pesados/análise , Síncrotrons , Poluentes Químicos da Água/análise , Qualidade da Água , Raios X
10.
Biol Trace Elem Res ; 200(4): 1485-1494, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34076844

RESUMO

A total of 158 serum samples of newly diagnosed type 2 diabetes patients and control subjects were analyzed using Synchrotron Radiation X-ray Fluorescence (SRXRF) technique. The microprobe XRF beam line-16 of Indus-2 synchrotron radiation facility at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore, India, was used to identify and quantify the elements K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, and Pb. A significant decrease in the mean concentrations of K, Ca, Ti, Cr, Mn, Ni, Zn, and As and an increase in the concentrations of V, Fe, Co, Cu, Se, and Pb were observed in the serum samples of the patient group when compared to the control group. It is hypothesized that the observed alterations in the elemental concentrations might have led to ineffective uptake of insulin and have interfered with glucose homeostasis by either directly or indirectly causing oxidative stress.


Assuntos
Diabetes Mellitus Tipo 2 , Oligoelementos , Fluorescência , Humanos , Índia , Síncrotrons , Oligoelementos/análise , Raios X
11.
Ecotoxicol Environ Saf ; 74(6): 1670-7, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21555153

RESUMO

The present investigation was carried out to evaluate metals concentration in ten vegetable crops growing in mixed industrial effluent irrigated agricultural field near Vadodara, Gujarat, India. Differential accumulation and translocation of various metals in selected vegetables plant species was observed. A higher concentration of metals were found in order of Fe>Mn>Zn>Cd>Cu>Pb>Cr>As in soil irrigated with industrial effluent than soil irrigated with tube well water; however, the concentration of As, Cr and Pb found below detection limit in tube well water irrigated soil. Metal accumulation in root and top of vegetables varied significantly both in relations to metal concentration in the soil and the plant genotype. Among ten vegetable species studied five vegetable species, i.e. Spinach, Radish, Tomato, Chili and Cabbage growing in mixed industrial effluent irrigated agricultural field showed high accumulation and translocation of toxic metals (As, Cd, Cr, Pb and Ni) in their edible parts, thus, their cultivation are unsafe with respect to possible transfer in food chain and health hazards. However, it is suggested that vegetable crops restricting toxic metal in non-edible port may be recommended for cultivation in such metal contaminated agricultural field.


Assuntos
Metais Pesados/análise , Poluentes do Solo/análise , Verduras/química , Poluentes Químicos da Água/análise , Irrigação Agrícola , Monitoramento Ambiental , Índia , Solo , Poluentes do Solo/metabolismo , Verduras/metabolismo , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/metabolismo
12.
J Synchrotron Radiat ; 17(2): 237-42, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20157277

RESUMO

In this paper the first practical application of kinoform lenses for the X-ray reflectivity characterization of thin layered materials is demonstrated. The focused X-ray beam generated from a kinoform lens, a line of nominal size approximately 50 microm x 2 microm, provides a unique possibility to measure the X-ray reflectivities of thin layered materials in sample scanning mode. Moreover, the small footprint of the X-ray beam, generated on the sample surface at grazing incidence angles, enables one to measure the absolute X-ray reflectivities. This approach has been tested by analyzing a few thin multilayer structures. The advantages achieved over the conventional X-ray reflectivity technique are discussed and demonstrated by measurements.

14.
Environ Monit Assess ; 162(1-4): 225-35, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19234750

RESUMO

We present diurnal variation of ambient ammonia (NH(3)) in relation with other trace gases (O(3), CO, NO, NO(2), and SO(2)) and meteorological parameters at an urban site of Delhi during winter period. For the first time, ambient ammonia (NH(3)) was monitored very precisely and continuously using ammonia analyzer, which operates on chemiluminescence method. NH(3) estimation efficiency of the chemiluminescence method (>90%) is much higher than the conventional chemical trapping method (reproducibility 4.5%). Ambient NH(3) concentration reaches its maxima (46.17 ppb) at night and minimum during midday. Result reveals that the ambient ammonia (NH(3)) concentration is positively correlated with ambient NO (r(2) = 0.79) and NO(2) (r (2) = 0.91) mixing ratio and negatively correlated with ambient temperature (r(2) = - 0.32). Wind direction and wind speed indicates that the nearby (approximately 500 m NW) agricultural fields may be major source of ambient NH(3) at the observational site.


Assuntos
Amônia/análise , Gases/química , Luminescência , Espectrofotometria Ultravioleta
15.
J Synchrotron Radiat ; 16(Pt 3): 325-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19395794

RESUMO

The unprecedented brilliance achieved by third-generation synchrotron sources and the availability of improved optics have opened up new opportunities for the study of materials at the micrometre and nanometre scale. Focusing the synchrotron radiation to smaller and smaller beams is having a huge impact on a wide research area at synchrotrons. The key to the exploitation of the improved sources is the development of novel optics that deliver narrow beams without loss of brilliance and coherence. Several types of synchrotron focusing optics are successfully fabricated using advanced miniaturization techniques. Kinoform refractive lenses are being developed for hard X-ray beamlines, and the first test results at Diamond are discussed in this paper.


Assuntos
Diamante , Germânio , Lentes , Refratometria/instrumentação , Síncrotrons/instrumentação , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Science ; 163(3864): 291-3, 1969 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-5762609

RESUMO

Sclerospora graminicola (Sacc.) Schroet., the obligate pathlogen causing downy mildew (green-ear) of pearl millet (Pennisetum typhoides Stapf. and Hubb.) has been successfully cultured for the first time on a known semisynthetic mediumn with no evident loss of fructifications. Sclerospora graminicola was first grown on host callus tissue and subsequently on a modification of White's basal medium that contained casein hydrolyzate (Oxoid). 2,4-dichlorophenoxyacetic acid, and kinetin.


Assuntos
Técnicas de Cultura , Fungos/crescimento & desenvolvimento , Meios de Cultura , Poaceae , Esporos
17.
Toxicol In Vitro ; 23(2): 295-301, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19135518

RESUMO

Exploration of antioxidants of plant origin and scientific validation of their efficacies has unraveled bioactives from natural sources. In this study, two terpenoids camphene and geraniol were assessed for their cytoprotective and antioxidant potential using t-BHP stressed rat alveolar macrophages. Effect of these test substances along with a known plant derived antioxidant quercetin was seen on cell viability, some oxidative stress markers as well as on mitochondrial membrane potential. Both the test substances geraniol and camphene increased the cell viability significantly as indicated by MTT assay and LDH release assay, during pre-treatment of test compound. Camphene and geraniol showed 29% (P<0.05) and 45% (P<0.05) increase in SOD activity, 28% and 120% (P<0.001) increase in GSH content and restored the mitochondrial membrane potential during pre-treatment as compared to stressed cells. Camphene and geraniol were found to significantly decrease lipid peroxidation, inhibit NO release (83.84% and 64.61%) and ROS generation in the pre-treated cells as compared to stressed cells. The test compounds also showed significant protection against ROS during post-treatment of the test compounds. Results indicate the pharmacological potential of these phytochemicals in lung inflammatory diseases where oxidative stress is a critical control point.


Assuntos
Antioxidantes/farmacologia , Macrófagos Alveolares/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Terpenos/farmacologia , terc-Butil Hidroperóxido/toxicidade , Monoterpenos Acíclicos , Animais , Monoterpenos Bicíclicos , Lavagem Broncoalveolar , Sobrevivência Celular/efeitos dos fármacos , Formazans/metabolismo , L-Lactato Desidrogenase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Macrófagos Alveolares/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Óxido Nítrico/metabolismo , Extratos Vegetais/farmacologia , Ratos , Ratos Wistar , Sais de Tetrazólio/metabolismo
18.
Natl J Maxillofac Surg ; 10(2): 141-145, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31798247

RESUMO

BACKGROUND: To assess changes in oral microflora in dental plaque from cancer patients within 7 days of the first course of chemotherapy and the relationship of the changes with mucositis. MATERIALS AND METHODS: Thirty cancer patients, divided into a test group undergoing chemotherapy and a control group not undergoing chemotherapy, were enrolled in this pilot study. Oral microflora was cultured from three samples of dental plaque at t0 (before chemotherapy), t1 (1 day after chemotherapy), and t2 (7 days after chemotherapy). Single and crossed descriptive analyses were used to establish prevalence, and the Chi-square test was used to establish the statistical significance of the differences observed in distributions (significance level: P < 0.05). RESULTS: In most patients (55%), oral microflora consisted mainly of Gram-positive cocci, while the remaining 45% of the bacterial flora also had periodontal-pathogenic species. No Porphyromonas gingivalis appeared in the test group. Actinobacillus was the least frequently found bacterium among periodontal pathogens in the test group, while Fusobacterium nucleatum was the most frequently found. No significant differences were found in quantitative bacterial changes between t0, t1, and t2 in either the test or control groups, or between the two groups. According to World Health Organization scores, oral mucositis developed in 10 patients (66.6%) in the test group. CONCLUSIONS: The results of this pilot study indicate that there were no changes in microflora in dental plaque in cancer patients within 7 days of the first course of chemotherapy. No correlations between oral mucositis and specific microorganisms were assessed.

19.
Mar Pollut Bull ; 140: 262-273, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30803642

RESUMO

The occurrence of microplastic particles were evaluated on beaches along the Indian coast from three different locations Girgaon Mumbai (Arabian sea coast), Tuticorin, and Dhanushkodi (Bay of Bengal coast). Density separation method was adopted for isolation of microplastics from sand. Isolated microplastics were characterized using three different analytical techniques e.g. fluorescence microscopy (after staining with Nile Red), FTIR and SEM-EDS techniques. Microplastic concentrations in beach sands were from 45 ±â€¯12 # MP kg-1 to 220 ±â€¯50 # MP kg-1 of dry sand. The order of abundance of plastic type was polyethylene (43%) > polyethylene terephthalate (17.3%) ≈ polystyrene (17%) > polypropylene (12.3%) > Others (11%) > polyvinylchloride (1.33%), and very similar profile was observed for all monitored locations. SEM images show microplastics surfaces with characteristic cracks, suggests their polymer aging, mechanical and oxidative weathering, which was found highest for the microplastics collected from Mumbai.


Assuntos
Praias , Monitoramento Ambiental/métodos , Plásticos/análise , Quartzo , Poluentes Químicos da Água/análise , Índia , Oceanos e Mares , Plásticos/química , Poluentes Químicos da Água/química
20.
Virus Res ; 135(1): 36-41, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18384900

RESUMO

The resurgence of Chikungunya virus (CHIKV) in the form of unprecedented explosive epidemic after a gap of 32 years in India is a point of major public health concern. In 2007 again there was outbreak in Kerala, India, affecting more than 25,000 cases with many reported mortalities. To understand the molecular basis of this high virulence and its implication in large-scale epidemic, a detailed systematic serological, virological and molecular investigation was undertaken with the epidemic samples of Kerala-2007. The comparative analysis of full genome sequence of Chikungunya virus isolate of 2007 with 2006 revealed three unique substitutions in structural and non-structural genes of 2007 isolate [two in E1 region (V14A and A226V) and one in Nsp1 (M184T)]. Our finding further substantiates the association of A226V shift in E1 gene with evolutionary success possibly due to adaptation in the mosquito vector with progression of epidemic, as observed in Reunion Island. This A226V shift which was absent in all 2006 Indian isolates, is found to be present in the four 2007 isolates, analysed in this study. These unique molecular features of the 2007 isolates with the progression of the epidemic from 2005 to 2007 demonstrate their high evolutionary and epidemic potential and thereby suggesting possible implication in higher magnitude and virulence of this outbreak.


Assuntos
Infecções por Alphavirus/epidemiologia , Infecções por Alphavirus/virologia , Substituição de Aminoácidos , Vírus Chikungunya/genética , Surtos de Doenças , Infecções por Alphavirus/imunologia , Sequência de Aminoácidos , Anticorpos Antivirais/sangue , Vírus Chikungunya/classificação , Vírus Chikungunya/isolamento & purificação , Vírus Chikungunya/patogenicidade , Genoma Viral , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Índia/epidemiologia , Mutação de Sentido Incorreto , Filogenia , RNA Viral/química , RNA Viral/genética , Análise de Sequência de DNA , Homologia de Sequência , Regiões não Traduzidas/química , Regiões não Traduzidas/genética , Proteínas Virais/química , Proteínas Virais/genética
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