Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 19 de 19
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Spectrochim Acta A Mol Biomol Spectrosc ; 318: 124464, 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-38768538

RESUMO

This work addresses the long-standing debate surrounding the origin of color variation in fluorite (CaF2) through a novel quantitative approach. By examining eight carefully selected fluorite samples having different hue of colors from the Amba Dongar mine in Gujarat, India, a rigorous quantitative analysis was conducted. This approach combined chemical compositional data and optical spectroscopic features to elucidate the relationship between elemental composition, concentration, and color variation in fluorite. Precise elemental concentration data for trace transition metals, alkali metals, and rare earth elements (REEs) were obtained through inductively coupled plasma mass spectroscopy (ICP-MS) analysis of powdered fluorite samples. Optical spectroscopic techniques, including UV-visible absorption, emission (photoluminescence and fluorescence), and Raman spectroscopy, were employed to capture characteristic spectral signatures for specific color of the study sample. The work unveils a strong correlation between specific elemental concentrations and observed spectral features, particularly influenced by alkaline metals, transition group elements, and REEs. Fluorite's optical absorption behavior lacks a clear pattern in UV and infrared wavelength ranges but correlates well with transition metal, alkaline element, and REE concentrations in visible wavelength regions, influencing coloration. Luminescent centers in the study fluorite samples correspond to specific REE concentrations, indicating a strong linkage between emission wavelengths with the presence of specific REE. UV-visible and fluorescence in fluorite result from trivalent REE or Eu2+ ions, with emission intensity affected by REE concentration and specific REE or combinations thereof. Raman spectroscopy identifies characteristic modes related to F-substitution and REE impurities, providing insights into fluorite's structural composition. This quantitative correlation between elemental composition and spectroscopic characteristics represents a novel contribution for understanding color variation mechanisms in fluorite. The comprehensive analysis of this present work underscores the intricate interplay of mineral composition, and element concentration particularly alkaline metals, transition group elements, and REEs, for variation in spectral signatures with variation in fluorite's visual attributes.

2.
Environ Toxicol Pharmacol ; 101: 104201, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37391053

RESUMO

This study investigated the deltamethrin (DMN) induced harmful effects on Pangasius hypophthalmus using enzymatic activity, haematological, and histopathological changes. LC50 value was 0.021 mg/L at 96 h, and sublethal toxicity was tested for 45 days at two `concentrations (i.e., 1/5th and 1/10th of LC50). Haematological parameters and enzymatic activities significantly changed between DMN-exposed and control groups (p < 0.05). Histopathologically, both DMN doses induced liver hyperemia, hepatic cell rupture, necrosis, hypertrepheoid bile duct, shifting nuclei, vascular haemorrhage, and hepatocyte degeneration, while in gill, secondary lamellae destruction, a fusion of adjacent gill lamellae, hypertrophy, hyperplasia, adhesion, and fusion were noticed. Kidney developed melanomacrophages, increased periglomerular and peritubular space, vacuolation, decreased glomerulus, hyaline droplets in tubular cells, loss of tubular epithelium, distal convoluted segment hypertrophy, and granular layer in brain pyramid and Purkinje cell nucleus. But, limiting pesticide impacts on freshwater fish and their habitat requires a holistic, cradle-to-grave approach and toxicological studies.


Assuntos
Peixes-Gato , Inseticidas , Tubarões , Poluentes Químicos da Água , Animais , Inseticidas/metabolismo , Fígado , Hipotálamo , Água Doce , Brânquias , Poluentes Químicos da Água/metabolismo
4.
Front Immunol ; 13: 803362, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774797

RESUMO

Research Impact: Cigarette smoke (CS) exposure is strongly associated with chronic obstructive pulmonary disease (COPD). In respiratory airways, CS exposure disrupts airway barrier functions, mucous/phlegm production, and basic immune responses of airway epithelial cells. Based on our recent identification of a specific immunomodulatory long noncoding RNA (lncRNA), we investigated its role in CS-induced responses in bronchial airways of cynomolgus macaque model of CS-induced COPD and in former smokers with and without COPD. The lncRNA was significantly upregulated in CS-induced macaque airways and in COPD airways that exhibited higher mucus expression and goblet cell hyperplasia. Experimental models of cells derived from COPD subjects recapitulated the augmented inflammation and mucus expression following the smoke challenge. Blocking of lncRNA expression in cell culture setting suppressed the smoke-induced and COPD-associated dysregulated mucoinflammatory response suggesting that this airway specific immunomodulatory lncRNA may represent a novel target to mitigate the smoke-mediated inflammation and mucus hyperexpression. Rationale: In conducting airways, CS disrupts airway epithelial functions, mucociliary clearances, and innate immune responses that are primarily orchestrated by human bronchial epithelial cells (HBECs). Mucus hypersecretion and dysregulated immune response are the hallmarks of chronic bronchitis (CB) that is often exacerbated by CS. Notably, we recently identified a long noncoding RNA (lncRNA) antisense to ICAM-1 (LASI) that mediates airway epithelial responses. Objective: To investigate the role of LASI lncRNA in CS-induced airway inflammation and mucin hyperexpression in an animal model of COPD, and in HBECs and lung tissues from former smokers with and without COPD. To interrogate LASI lncRNA role in CS-mediated airway mucoinflammatory responses by targeted gene editing. Methods: Small airway tissue sections from cynomolgus macaques exposed to long-term mainstream CS, and those from former smokers with and without COPD were analyzed. The structured-illumination imaging, RNA fluorescence in-situ hybridization (FISH), and qRT-PCR were used to characterize lncRNA expression and the expression of inflammatory factors and airway mucins in a cell culture model of CS extract (CSE) exposure using HBECs from COPD (CHBEs) in comparison with cells from normal control (NHBEs) subjects. The protein levels of mucin MUC5AC, and inflammatory factors ICAM-1, and IL-6 were determined using specific ELISAs. RNA silencing was used to block LASI lncRNA expression and lentivirus encoding LASI lncRNA was used to achieve LASI overexpression (LASI-OE). Results: Compared to controls, LASI lncRNA was upregulated in CS-exposed macaques and in COPD smoker airways, correlating with mucus hyperexpression and mucus cell hyperplasia in severe COPD airways. At baseline, the unstimulated CHBEs showed increased LASI lncRNA expression with higher expression of secretory mucin MUC5AC, and inflammatory factors, ICAM-1, and IL-6 compared to NHBEs. CSE exposure of CHBEs resulted in augmented inflammation and mucus expression compared to controls. While RNA silencing-mediated LASI knockdown suppressed the mucoinflammatory response, cells overexpressing LASI lncRNA showed elevated mRNA levels of inflammatory factors. Conclusions: Altogether, LASI lncRNA may represent a novel target to control the smoke-mediated dysregulation in airway responses and COPD exacerbations.


Assuntos
Fumar Cigarros , Doença Pulmonar Obstrutiva Crônica , RNA Longo não Codificante , Animais , Fumar Cigarros/efeitos adversos , Células Caliciformes/metabolismo , Humanos , Hiperplasia , Inflamação , Molécula 1 de Adesão Intercelular/genética , Interleucina-6 , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , RNA Longo não Codificante/genética , Nicotiana/efeitos adversos
5.
J Family Med Prim Care ; 9(1): 327-331, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32110613

RESUMO

BACKGROUND: Extracts of Piper betel are used for the treatment of various ailments since ages due to its essential properties like antioxidant, anticancer, anti-allergic etc. In the present study antioxidant activity for Piper betel leaf extract and Eugenol was assessed. Eugenol was taken as marker compound. METHODS: Nitric oxide, Hydroxyl radical and Reducing power assay methods were carried out for assessment of antioxidant activity of Piper betel. RESULTS: The antioxidant activity for Nitric oxide, Hydroxyl radical and Reducing power assay at 1000 to 62.5µg/ml was performed. The antioxidant activity of Piper betel leaf extract exhibited the IC50 value for Nitric oxide and Hydroxyl radical >1000 whereas Eugenol exhibited the IC50 value 114.34± 0.46 and 306.44 ± 5.28 respectively, for reducing power assay (RPA) Piper betel leaf extract and Eugenol revealed the RPA value ranging from 0.44-0.08 and 0.53-0.12. CONCLUSION: The benefits of Piper betel have been mentioned in our ancient texts. Keeping in view the emergence of various diseases and the benefits of Piper betei, there is need that every effort should be made to revive this treasure of nature into our daily supplement.

6.
Front Aging Neurosci ; 10: 291, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30356847

RESUMO

Neurological disorders are the biggest concern globally. Out of ~36 million human immunodeficiency virus (HIV) positive people, about 30%-60% exhibit neurological disorders, including dementia and Alzheimer's disease (AD) like pathology. In AD or AD like neurological disorders, the pathogenesis is mainly due to the abnormal accumulation of extracellular amyloid beta (Aß). In this era of antiretroviral therapy, the life span of the HIV-infected individuals has increased leading towards increased neurocognitive dysfunction in nearly 30% of HIV-infected individuals, specifically older people. Deposition of the Aß plaques in the CNS is one the major phenomenon happening in aging HIV patients. ART suppresses the viral replication, but the neurotoxic protein (Tat) is still produced and results in increased levels of Aß. Furthermore, drugs of abuse like cocaine (coc) is known to induce the HIV associated neurocognitive disorders as well as the Aß secretion. To target the Tat and coc induced Aß secretion, we propose a potent bifunctional molecule Withaferin A (WA) which may act as a neuro-protectant against Aß neurotoxicity. In this study, we show that WA reduces secreted Aß and induced neurotoxicity in amyloid precursor protein (APP)-plasmid transfected SH-SY5Y cells (SH-APP). In this study, we show that in SH-APP cells, Aß secretion is induced in the presence of HIV-1 Tat (neurotoxic) and drug of abuse coc. Our fluorescent microscopy studies show the increased concentration of Aß40 in Tat (50 ng/ml) and coc (0.1 µM) treated SH-APP cells as compared to control. Our dose optimization study show, lower concentrations (0.5-2 µM) of WA significantly reduce the Aß40 levels, without inducing cytotoxicity in the SH-APP cells. Additionally, WA reduces the Tat and cocaine induced Aß levels. Therefore, we propose that Aß aggregation is induced by the presence of Tat and coc and WA is potent in reducing the secreted Aß and induced neurotoxicity. Our study provides new opportunities for exploring the pathophysiology and targeting the neurological disorders.

7.
Indian J Med Paediatr Oncol ; 38(2): 236-239, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28900341

RESUMO

Amyloidosis is a multi-systemic diffusely infiltrating disease due to extracellular deposition of protein-mucopolysaccharide complexes. The type of protein deposited determines the subgroup of amyloid. Hepatic amyloidosis is a rare infiltrating disease affecting the hepatic parenchyma. A wide range of clinical presentation and atypical imaging findings delay the diagnosis of amyloidosis, while tissue biopsy demonstrating amyloid deposits is vital for a definitive diagnosis.

9.
Nat Commun ; 6: 7154, 2015 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-25981180

RESUMO

Prediction of Indian summer monsoon rainfall (ISMR) is at the heart of tropical climate prediction. Despite enormous progress having been made in predicting ISMR since 1886, the operational forecasts during recent decades (1989-2012) have little skill. Here we show, with both dynamical and physical-empirical models, that this recent failure is largely due to the models' inability to capture new predictability sources emerging during recent global warming, that is, the development of the central-Pacific El Nino-Southern Oscillation (CP-ENSO), the rapid deepening of the Asian Low and the strengthening of North and South Pacific Highs during boreal spring. A physical-empirical model that captures these new predictors can produce an independent forecast skill of 0.51 for 1989-2012 and a 92-year retrospective forecast skill of 0.64 for 1921-2012. The recent low skills of the dynamical models are attributed to deficiencies in capturing the developing CP-ENSO and anomalous Asian Low. The results reveal a considerable gap between ISMR prediction skill and predictability.

10.
Ann Med Health Sci Res ; 4(4): 583-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25221709

RESUMO

BACKGROUND: The present study is aimed at analyzing the expression of inducible nitric oxide synthase (iNOS) in the epithelial lining of odontogenic keratocyst (OKC), dentigerous cyst (DC), radicular cyst (RC) in order to understand the possible role of iNOS with special reference to its neoplastic nature and local aggressive of cysts. AIM: The primary aim of the following study is to analyze the immunohistochemical expression of iNOS and secondary aim is to compare the iNOS expression, pattern and intensity of staining among the epithelial linings of OKC, DC and RC. MATERIALS AND METHODS: iNOS in the epithelial lining cells were analyzing in 10 OKC's, 10 DC's and 10 RC's using immunohistochemistry. The percentage of positive cells was assessed and presented as mean ± standard deviation. The correlation with respect to the intensity and percentage of staining within the epithelial linings of OKCs, DCs and RCs was carried out using (analysis of variance and Student's t-test) Chi-square test. RESULTS: Staining intensity of iNOS portion was seen in the entire thickness of the epithelial linings of OKC, whereas in DC's only one case had entire thickness of the epithelial lining staining and in RC's none of the cases showed entire thickness of staining. On comparing the staining intensity of iNOS between OKC, DC and RC groups, using Chi-square test, there was a statistically significant difference between these groups (P < 0.01). On analyzing the immuno-reactivity of iNOS in OKC, DC and RC there was a positive variable expression iNOS between the cysts. CONCLUSION: iNOS was over expressed in OKCs when compared with DC and RC suggesting that iNOS may contribute to the aggressive behavior of OKC. This is yet another evidence to support that OKC is the neoplasm.

11.
Phys Rev Lett ; 112(5): 052501, 2014 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-24580588

RESUMO

Excited states in 102Rh, populated in the fusion-evaporation reaction Zr94(11B,3n)102Rh at a beam energy of 36 MeV, were studied using the Indian National Gamma Array spectrometer at Inter University Accelerator Center, New Delhi. The angular correlations and the electromagnetic character of some of the gamma-ray transitions observed were investigated in detail. A new chiral candidate sister band was found. Lifetimes of exited states in both chiral candidate bands of 102Rh were measured for the first time in the A∼100 mass region by means of the Doppler-shift attenuation technique. The derived reduced transition probabilities are compared to the predictions of the two quasiparticles plus triaxial rotor model. Both experimental results and calculations do not support the presence of static chirality in 102Rh.

12.
Indian J Radiol Imaging ; 19(4): 314-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19881113

RESUMO

Cerebrotendinous xanthomatosis is a rare genetic disorder. We present and discuss the clinical, radiological, and histopathologic findings in a 36-year-old woman who had juvenile cataract, childhood diarrhea, mental retardation, cerebellar ataxia, and bilateral Achilles tendon xanthomas. She was thoroughly investigated radiologically and biopsy confirmed the diagnosis of xanthomas.

13.
Water Sci Technol ; 52(1-2): 237-44, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16180434

RESUMO

The effect of oxidative and thermo-oxidative co-treatment of excess municipal sludge was investigated. A mixture of primary and waste activated sludge was anaerobically treated using two different configurations: i) two stages and ii) a single stage with recycling. Oxidative or thermo-oxidative co-treatment placed in between the reactor or in the recycle line was studied. A two-stage configuration with no co-treatment served as a control and resulted in 50.1% overall solids removal. Compared to the control, an increase in solids removal of 10.8 and 2.7% was observed when oxidative co-treatment was placed between reactors and in the recycle line respectively. When thermo-oxidative co-treatment was placed between the two stages or in the recycle line an increase in solids removal of 25.1 and 26.9% respectively was observed. The performances of the different configurations were also evaluated with parameters such as COD, TKN, ammonia, and fecal coliform concentration.


Assuntos
Reatores Biológicos/microbiologia , Temperatura Alta , Peróxido de Hidrogênio , Esgotos , Eliminação de Resíduos Líquidos/métodos , Bactérias Anaeróbias/metabolismo , Ácidos Graxos Voláteis/metabolismo , Metano/metabolismo , Oxirredução , Fatores de Tempo
14.
Lung Cancer ; 49 Suppl 1: S9-12, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15950810

RESUMO

Primary exposure to asbestos in India can be encountered in the form of asbestos mining, asbestos cement industries, asbestos processing unit and during renovation and demolition of old asbestos cemented roof or other structures as well as modern electrical as well as mechanical appliances in which asbestos is still found. Ultimately construction workers, electricians, vehicle mechanics and other workers in the building trades who are exposed to asbestos inhale hundreds and thousands of amphiboles, which causes lung damage. It is being mined in India at places such as Andhra Pradesh (Pulivendla), Jharkand (Roro), Rajasthan (Ajmer, Bhilwara, Udaipur, Rajsamand) and the common problem faced by the locals are asbestosis through air and fluorosis through drinking water. The problem continues to be in India as well as other developing countries. Also, India import and re-export asbestos to other countries and workers at shipyard, transport of the hazardous material on road and roadside residents all are vulnerable to this uncommon disease. The signs and symptoms generally found with the workers are shortness of breath, persistent and productive cough due to pulmonary fibrosis can show up many years after the asbestos exposure.


Assuntos
Asbestose/epidemiologia , Amianto/efeitos adversos , Asbestose/etiologia , Feminino , Humanos , Índia/epidemiologia , Masculino
15.
J Environ Monit ; 5(3): 427-34, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12833986

RESUMO

Suspended Particulate Matter (SPM), surface (bed sediments) and short length cores of sediments collected from the largest tributary of the river Ganges, namely the river Yamuna, were analysed for total mercury as well as its fractionation in various size and chemical sites in the sediments following standard procedures. Also, attempts were made to determine the vertical distribution in sediments in relation to the recent timescale of a few decades. Our observations indicate that the SPM in general showed higher levels of total mercury compared to the surface sediments while at places the enhancement could be by a factor of 10, say around 25 microg g(-1) in the downstream region that integrates the industrial midstream and agricultural downstream terrain near its confluence with the Ganges. Surface sediments in the upstream direction near the Himalayan foothills and SPM in the lower reaches showed significant high Index of Geoaccumulation (Igeo) as defined by Müller. Size fractionation studies indicate that the finer fraction preferentially showed higher levels of mercury while in the lower reaches of the river, the total mercury is equitably distributed among all size fractions. The proportion of the residual fraction of mercury in relation to mobile fractions, in general decreases downstream towards its confluence with the Ganges river. In sediment cores, the vertical distribution show systematic peaks of mercury indicating that addition of this toxic metal to the aquatic system is in direct proportion to the increase in various types of human activities such as thermal power plants, land use changes (urbanisation) in the midstream region and intensive fertiliser application in lower reaches of this vast river basin.


Assuntos
Sedimentos Geológicos/química , Mercúrio/análise , Poluentes da Água/análise , Agricultura , Monitoramento Ambiental , Fertilizantes , Índia , Tamanho da Partícula , Centrais Elétricas
16.
J Environ Monit ; 4(6): 821-2, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12509035

RESUMO

The natural abundance of fluoride in soils of the Ajmer distict, Rajasthan was examined. From undisturbed soil, the top 15 cm of the profile was examined and the soil split into fractions based on sand, silt and clay particle size. Clay contained a high amount of fluoride, whereas sand and silts are enriched with much less fluoride. The relation between the soil fractions in observed clay fraction fluoride content matched groundwater fluoride variation. However, the enrichment of fluoride material extracted from the largest soil fraction had considerably lower amounts of clay relative to that from the smaller fractions.


Assuntos
Fluoretos/análise , Solo , Silicatos de Alumínio/química , Argila , Monitoramento Ambiental , Índia
17.
Placenta ; 21(5-6): 501-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10940200

RESUMO

Peroxidase (Donor: H(2)O(2)oxidoreductase EC 1.11.1.7) from human term placentae of non-smokers was purified to homogeneity by a combination of NH(4)Cl extraction, affinity chromatography, (NH(4))(2)SO(4)precipitation, ion-exchange and gel filtration chromatography. The homogeneity of purified human placental peroxidase (HTPP) was confirmed by gel filtration, reverse phase high performance liquid chromatography (HPLC) and SDS-PAGE. Peroxidase was found to be a membrane bound enzyme. A high concentration of NH(4)Cl (1.2 m) was needed to extract and solublize the enzyme. Removal of the salt resulted in irreversible precipitation of the enzyme. The protein exhibited a molecular mass of 126 000 kDa according to gel filtration and approximately 60 000 kDa by SDS-PAGE, indicating that the peroxidase is a homodimer. The purified peroxidase showed an optimum pH range of 7 to 8.5 and the K(m)for H(2)O(2)and guaiacol were found to be 0.08 m m and 10.0 m m, respectively. The purified peroxidase oxidized several substrates, namely potassium iodide, tetramethyl benzidine, guaiacol, ortho dianisidne and tyrosine. The enzyme was resistant to thermal denaturation up to 70 degrees C and also to chaotropic agents, guanidinium chloride and urea. Spectral properties indicated the presence of Soret band at 433 which shifted to 451 nm on complexation with cyanide. The circular dichroism studies showed that HTPP has a predominantly helical secondary structure. The enzyme showed similarities to the myeloperoxidase with regard to spectral and catalytical properties but differed significantly in amino acid composition, the R(z)value and molecular mass. Purified HTPP differed from eosinophil peroxidase in all physico-chemical properties indicating that it is not of eosinophil origin, but may represent a distinct, constitutive peroxidase in human placenta. Further, purified peroxidase catalyzed oxidation of benzo(a)pyrene-7, 8-dihydrodiol in presence of tyrosine and hydrogen peroxide to BP-tetrols, the hydrolytic products of BP-diol-epoxides, demonstrating the ability of peroxidase in bioactivation of benzo(a)pyrene in human placenta.


Assuntos
Di-Hidroxi-Di-Hidrobenzopirenos/metabolismo , Peroxidase/isolamento & purificação , Placenta/enzimologia , Adulto , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Feminino , Humanos , Peso Molecular , Peroxidase/química , Peroxidase/metabolismo , Gravidez , Terceiro Trimestre da Gravidez , Fumar , Especificidade por Substrato
19.
Hum Exp Toxicol ; 14(6): 503-6, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8519527

RESUMO

Human placenta, umbilical cord blood, maternal blood and breast milk samples from mothers were analysed for the presence of selected polycyclic aromatic hydrocarbons (PAHs). Benzo(a) pyrene (B(a)P), dibenzo(a,c)anthracene (DBA) and chrysene (Chy) were detected in all the four types of sample. Levels of dibenzo(a,c)anthracene were higher in the above samples compared with the other two PAHs. Umbilical cord blood and breast milk samples showed relatively high concentrations of all the three PAHs and thus demonstrated that the developing foetus/new born were exposed to these carcinogenic environmental contaminants. The possible implications of PAHs in relation to human health are discussed.


Assuntos
Sangue Fetal/metabolismo , Leite Humano/química , Placenta/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Adulto , Benzo(a)Antracenos/análise , Benzo(a)Antracenos/metabolismo , Benzo(a)pireno/metabolismo , Crisenos/sangue , Crisenos/metabolismo , Exposição Ambiental , Poluentes Ambientais/sangue , Poluentes Ambientais/metabolismo , Feminino , Humanos , Índia , Hidrocarbonetos Policíclicos Aromáticos/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...