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1.
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
2.
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.

3.
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.

4.
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
5.
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
6.
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.

7.
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
8.
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
9.
Mar Pollut Bull ; 131(Pt A): 453-459, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29886971

RESUMO

The sedimentation rates in Arctic fjords are influenced by the changes in the glacial inputs. The recent studies have indicated the retreat of glaciers due to climate change and subsequent increase in melt water outflow with high content of debris. The debris may contain natural and anthropogenically originated contaminants. The present study analysed the sedimentation rate in inner Kongsfjorden, Ny-Ålesund, Svalbard using 210Pb/210Po dating technique. The sedimentation rate ranged between 0.22 and 0.37 cm/year during the last 112 years. The average sedimentation rate obtained was 0.28 cm/y. The rate has been increased during the last 20 years and it might be due to the increased influx of glacial melt water containing debris. Metals and other elements showed an increasing trend towards the surface and observed high deposition rate since 1970s, indicating influence of industrial emissions and it can be a potential threat to Arctic biota.


Assuntos
Sedimentos Geológicos/análise , Metais/análise , Poluentes Químicos da Água/análise , Regiões Árticas , Monitoramento Ambiental/métodos , Estuários , Sedimentos Geológicos/química , Camada de Gelo , Radioisótopos de Chumbo/análise , Polônio/análise , Svalbard
10.
Appl Radiat Isot ; 135: 57-60, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29396212

RESUMO

A method was optimized for detecting trace elements in sea water using Energy dispersive X-ray fluorescence (EDXRF) technique. Sea water samples were pre-concentrated using ammonium pyrrolidinedithiocarbamate (APDC) as chelating agent and methyl isobutyl ketone (MIBK) as organic phase. The preconcentrated samples were dried to form thin films on mylar substrate and analysed using EDXRF spectrometer. The multi-element standard samples prepared in synthetic sea water were used for EDXRF instrument calibration. The instrument was calibrated for 11 elements namely As, Cd, Co, Cr, Fe, Ga, Pb, Se, Sc, V and Zn using linear regression method for concentration up to 200 ppb. The detection limits achieved for As, Cd, Co, Cr, Fe, Ga, Pb, Se, Sc, V and Zn were 13, 70, 5.1, 36, 15, 36, 23, 11, 20, 13 and 40 ppb respectively. The optimized method was used for determination of elements in sea water collected from the Thane creek, Mumbai, India. The results were checked for accuracy by comparing it with inductively coupled plasma atomic emission spectroscopy (ICP AES) technique. The comparison showed the discrepancy of results to be insignificant at 95% confidence level.

11.
Appl Radiat Isot ; 128: 210-215, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28735114

RESUMO

Determination of impurities namely Ca, Mn, Fe, Ni, Zn, Sr and Pb in graphite by energy dispersive X-ray fluorescence spectrometry is described using microfocused synchrotron radiation. The internal standard and standard addition methodologies were adopted for quantification and the results were compared with tube-based X-ray fluorescence spectrometry. Analysis of the results by the F and t-tests revealed their statistical equivalence. Synchrotron measurements improved the detection limits by an order of magnitude compared to the tube based technique. Cr and Zr, which were below the quantification limit in tube based technique, were also quantified by synchrotron based technique.

12.
Environ Toxicol Pharmacol ; 50: 58-66, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28131077

RESUMO

We report levels of polycyclic aromatic hydrocarbons in sediment, seawater, fish and crab samples from Thane creek, India. Concentrations of sixteen USEPA PAH in sediments varies from 874 to 1925ngg-1, dry weight (dw) in winter, between 219-495ngg-1 in summer. In seawater Σ16 PAHs concentration during winter was recorded 706±193ngL-1, and during summer 337±79ngL-1. Total concentrations of PAHs in consumable portion of lizard fish, bombay duck and crab were found 156.8±18 and 122±24.5ngg-1, 117.4±17.65ngg-1 and 95.8±16.2ngg-1, 348±94.5 and 95.62±31.9ngg-1 wet weight (ww) in summer and winter respectively. PAHs concentration were compared with sediments quality guidelines viz. ERL-ERM, TEL-PEL indexes for finding ecotoxicological risk on marine organism. The ILCR values were above public screening criteria for carcinogens.


Assuntos
Monitoramento Ambiental/métodos , Poluição Ambiental/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Animais , Organismos Aquáticos/química , Peixes , Sedimentos Geológicos/análise , Humanos , Índia , Medição de Risco , Estações do Ano , Água do Mar/análise , Frutos do Mar/análise
13.
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.

14.
Plant Physiol Biochem ; 110: 118-127, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27622847

RESUMO

This report focuses on application of zinc oxide nanoparticles (ZnONPs) carrying phycomolecule ligands as a novel plant growth promoter aimed at increasing the crop productivity. The present investigation examined the effect of ZnONPs on plant growth characteristics, and associated biochemical changes in cotton (Gossypium hirsutum L.) following growth in a range of concentrations (25-200 mg L-l ZnONPs) in combination with 100 mM P in a hydroponic system. Treated plants registered an increase in growth and total biomass by 130.6% and 131%, respectively, over control. Results demonstrated a significant increase in the level of chlorophyll a (141.6%), b (134.7%), carotenoids (138.6%), and total soluble protein contents (179.4%); at the same time, a significant reduction (68%) in the level of malondialdehyde (MDA) in leaves with respect to control. Interestingly, a significant increase in superoxide dismutase (SOD, 264.2%), and peroxidase (POX, 182.8%) enzyme activities followed by a decrease in the catalase (CAT) activity, in response to above treatments. These results suggest that bioengineered ZnONPs interact with meristematic cells triggering biochemical pathways conducive to an accumulation of biomass. Further investigations will map out the mode of action involved in growth promotion.


Assuntos
Gossypium/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Fósforo/farmacologia , Óxido de Zinco/farmacologia , Biomassa , Carotenoides/metabolismo , Catalase/metabolismo , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Gossypium/crescimento & desenvolvimento , Gossypium/metabolismo , Hidroponia/métodos , Malondialdeído/metabolismo , Meristema/efeitos dos fármacos , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Peroxidase/metabolismo , Fósforo/química , Proteínas de Plantas/metabolismo , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Superóxido Dismutase/metabolismo , Propriedades de Superfície , Difração de Raios X , Óxido de Zinco/química
15.
J Environ Radioact ; 162-163: 251-257, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27294663

RESUMO

In this study, size fractionated mass and 210Po activity concentrations in mainstream cigarette smoke (MCS) were monitored for three popular cigarette brands. Size segregated collection of MCS was carried out using a cascade type impactor, while mass and 210Po activity concentration were analyzed gravimetrically and alpha spectrometry (following the radiochemical separation) respectively. Multiple-Path Particle Dosimetry (MPPD V2.11) model is used for prediction of deposition fraction calculations for the MCS deposition in different compartment of human respiratory tract. The activity concentration of 210Po is founds 10.56 ± 2.46 mBq per cigarette for the tested cigarette brands. 210Po size distribution indicates most of this associates with fine fraction (Dp < 2.23 µm) of cigarette smoke. The committed annual effective dose to smokers (smoking on an average 20 cigarette a day), considering the 210Po and 210Pb concentrations (assuming it is in secular equilibrium with 210Po) in MCS, was estimated between 0.22 and 0.40 mSv, with mean value of 0.30 mSv for tested cigarette brands. Considering the risk factor of fatal cancer due to radiation exposure of lung (exposure time of 30 years); the average collective estimated fatal cancer risk is estimated as 1.5 × 10-4 due to 210Po and 210Pb exposure to smokers.


Assuntos
Polônio/análise , Humanos , Exposição por Inalação/efeitos adversos , Exposição por Inalação/análise , Radioisótopos de Chumbo/análise , Pulmão/efeitos dos fármacos , Fatores de Risco , Fumar/efeitos adversos , Nicotiana/efeitos adversos
16.
Environ Sci Pollut Res Int ; 23(18): 18789-99, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27316650

RESUMO

Endocrine disrupting chemicals (EDCs) are responsible for inappropriate development and they alter the hormonal and homeostatic systems of organism. Phthalates (PAEs), bisphenol A (BPA) and other EDCs were monitored in surface sediments at different stations across Thane Creek, India. Analysis of PAEs was carried out using GC-MS technique, while BPA and other EDCs were analyzing on UPLC-PDA instrument. Di-n-butyl phthalate (DBP) had the highest concentration among all fourteen analyzed phthalates ranges between 0.13 and 0.4 mg kg(-1); and was detectable in all sediment samples. Strong correlation (r = 0.95, p < 0.01) was observed between total organic carbon (TOC, %) and total PAEs. BPA was also detected in all samples; average BPA concentration varies from 16.3 to 35.79 µg kg(-1) with mean value 25.15 µg kg(-1) dry weight of sediment. Synthetic EDCs such as 4-para-nonylphenol (NP) and 4-tert-octylphenol (OP) were also analyzed; and their average concentrations were founds to be 356.5 and 176 µg kg(-1), respectively. Estrone (E1), 17ß-estradiol (E2), and 17α-ethinylestradiol (EE2) were the main contributors to the overall estradiol equivalent concentration (EEQs) in sediment, their average total percentage contributions is more than 90 %.


Assuntos
Disruptores Endócrinos/análise , Monitoramento Ambiental , Estuários , Poluentes Químicos da Água/análise , Compostos Benzidrílicos/análise , Dibutilftalato/análise , Estradiol/análise , Estrona/análise , Etinilestradiol/análise , Cromatografia Gasosa-Espectrometria de Massas , Índia , Fenóis/análise
17.
Cell Death Discov ; 22016 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-27019748

RESUMO

Caspase-2 plays an important role in apoptosis induced by several stimuli, including oxidative stress. However, the subcellular localization of caspase-2, particularly its presence in the mitochondria, is unclear. It is also not known if cytosolic caspase-2 translocates to the mitochondria to trigger the intrinsic pathway of apoptosis or if caspase-2 is constitutively present in the mitochondria that then selectively mediates this apoptotic effect. Here, we demonstrate the presence of caspase-2 in purified mitochondrial fractions from in vitro-cultured cells and in liver hepatocytes using immunoblots and confocal microscopy. We show that mitochondrial caspase-2 is functionally active by performing fluorescence resonance energy transfer analyses using a mitochondrially targeted substrate flanked by donor and acceptor fluorophores. Cell-free apoptotic assays involving recombination of nuclear, cytosolic and mitochondrial fractions from the livers of wild type and Casp2-/- mice clearly point to a direct functional role for mitochondrial caspase-2 in apoptosis. Furthermore, cytochrome c release from Casp2-/- cells is decreased as compared with controls upon treatment with agents inducing mitochondrial dysfunction. Finally, we show that Casp2-/- primary skin fibroblasts are protected from oxidants that target the mitochondrial electron transport chain. Taken together, our results demonstrate that caspase-2 exists in the mitochondria and that it is essential for mitochondrial oxidative stress-induced apoptosis.

19.
Rev Sci Instrum ; 86(5): 055102, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26026553

RESUMO

A new multipurpose x-ray reflectometer station has been developed and augmented at the microfocus beamline (BL-16) of Indus-2 synchrotron radiation source to facilitate synchronous measurements of specular x-ray reflectivity and grazing incidence x-ray fluorescence emission from thin layered structures. The design and various salient features of the x-ray reflectometer are discussed. The performance of the reflectometer has been evaluated by analyzing several thin layered structures having different surface interface properties. The results reveal in-depth information for precise determination of surface and interface properties of thin layered materials demonstrating the immense potential of the combined measurements of x-ray reflectivity and grazing incidence fluorescence on a single reflectometer.

20.
JNMA J Nepal Med Assoc ; 53(197): 12-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26983041

RESUMO

INTRODUCTION: High negative appendectomy rate still prevails on conventional histologic examination. Increased mural eosinophilic infiltrate had been observed in acute appendicitis. Present study aimed to evaluate the role of mural eosinophils in clinically suspected acute appendicitis but histological normal appendix, as an indicator of acute inflammation, alone or in association with edema and to estimate the cut off value for high eosinophil count for the diagnosis of acute appendicitis. METHODS: A prospective cross sectional study was conducted on appendectomy specimens which were categorized into three groups of classical acute appendicitis, negative appendectomy and control. HandE and Giemsa stained section were studied for the presence of mural eosinophilic infiltrate, mast cells and edema. RESULTS: Of total 170 cases, group 1 comprised of 68 cases, group 2 consisted of 78 cases and group 3 consisted of 24 cases. Mean eosinophil and mast cell counts in the muscularis propria were significantly higher in CAA and NA categories when compared to control group. Positive association was found between high eosinophil count and edema in CAA and NA categories. Cut off value of ≥6/ mm2 for mural eosinophil count was not significantly different in between NA and control categories. CONCLUSIONS: Increased mural eosinophils were significantly present in acute appendicitis and clinically suspected acute appendicitis but histological normal appendix when compared with control group. Sole presence of increased mural eosinophils might represent acute inflammation. However, cut off value for high eosinophil count could not be established to suggest acute appendicitis.


Assuntos
Apendicite/diagnóstico , Apendicite/imunologia , Apêndice/imunologia , Eosinófilos/imunologia , Adulto , Apendicectomia , Apendicite/cirurgia , Biomarcadores/metabolismo , Estudos Transversais , Edema/imunologia , Feminino , Humanos , Inflamação/imunologia , Masculino , Mastócitos/imunologia , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença
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