Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Comput Biol Chem ; 110: 108038, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38461796

RESUMO

The local disruptions caused by the genes of one disease can influence the pathways associated with the other diseases resulting in comorbidity. For gene therapies, it is necessary to prioritize the key genes that regulate common biological mechanisms to tackle the issues caused by overlapping diseases. This work proposes a clustering-based computational approach for prioritising the comorbid genes within the overlapping disease modules by analyzing Protein-Protein Interaction networks. For this, a sub-network with gene interactions of the disease pair was extracted from the interactome. The edge weights are assigned by combining the pairwise gene expression correlation and betweenness centrality scores. Further, a weighted graph clustering algorithm is applied and dominant nodes of high-density clusters are ranked based on clustering coefficients and neighborhood connectivity. Case studies based on neurodegenerative diseases such as Amyotrophic Lateral Sclerosis- Spinal Muscular Atrophy (ALS-SMA) pair and cancers such as Ovarian Carcinoma-Invasive Ductal Breast Carcinoma (OC-IDBC) pair were conducted to examine the efficacy of the proposed method. To identify the mechanistic role of top-ranked genes, we used Functional and Pathway enrichment analysis, connectivity analysis with leave-one-out (LOO) method, analysis of associated disease-related protein complexes, and prioritization tools such as TOPPGENE and Heml2.0. From pathway analysis, it was observed that the top 10 genes obtained using the proposed method were associated with 10 pathways in ALS-SMA comorbidity and 15 in the case of OC-IDBC, while that in similar methods like SAPDSB and S2B were 4, 6 respectively for ALS-SMA and 9, 10 respectively for OC-IDBC. In both case studies, 70 % of the disease-specific benchmark protein complexes were linked to top-ranked genes of the proposed method while that of SAPDSB and S2B were 55 % and 60 % respectively. Additionally, it was found that the removal of the top 10 genes disconnect the network into 14 distinct components in the case of ALS-SMA and 9 in the case of OC-IDBC. The experimental results shows that the proposed method can be effectively used for identifying key genes in comorbidity and can offer insights about the intricate molecular relationship driving comorbid diseases.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124125, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38461561

RESUMO

In this research work, we have successfully synthesized the CeO2/Co3O4/g-C3N4 ternary nanocomposite for hydrothermal method for photocatalytic applications. The synthesized nanocomposites were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, Field emission scanning electron microscopy (FE-SEM), Transmission electron microscopy TEM, Photoluminescent spectra (PL), X-ray photoelectron spectroscopy (XPS), Brunauer- Emmett-Teller (BET) and Ultraviolet diffuse reflectance spectroscopy (UV-DRS) technique. As per the optical spectroscopic investigations CeO2/Co3O4/g-C3N4 ternary nanocomposite exhibited the high optical absorption range and its band gap is reduced from 2.95 eV to1.83 eV. The PL spectra showed the lowered emission peak intensity of ternary nanocomposite which is revealed that the better charge separation and slow recombination of electron hole pairs. The highest photocatalytic degradation efficiency of CeO2/Co3O4/g-C3N4 ternary nanocomposite showed 93 % and 86 % towards the pollutant methylene blue and Rhodamine B. Moreover, photodegradation of the pollutants followed pseudo-first order kinetics with a very high-rate constant of 0.02211 min-1 and 0.017756 min-1. Additionally, the ternary nano catalyst was delivered the remarkable stability performance even after five cycles. This research may provide a low-cost approach for synthesized visible light responsive catalysts for use in environmental remediation applications.

3.
Mol Biotechnol ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37993758

RESUMO

Triple-negative breast cancer (TNBC) doesn't have well-defined molecular targets making it unable to treat with chemotherapy also have faster metastatic rate and worse survival rate. In the current study we aim to target TNBC through eco-friendly green synthesized silver nanoparticles having anti-cancer phytoconstituents from the traditional anti-cancer medicinal plant Eclipta alba. Green synthesized silver nanoparticles (AgNPs) are agglomerates of spherical shaped 40-60 nm sized showing characteristic light absorption at 437 nm, banding pattern at 1479, 1285, 1036, and 471 showing and further X-ray diffraction pattern confirm face-centered cubic crystal silver structure exist in the green synthesized silver nanoparticle preparation. Further in vitro anti-oxidant analysis results revealed that green synthesized AgNPs showed 2.6-fold higher anti-oxidant potential (IC50 15.70 g/ml) than that of aqueous plant leaf extract (IC50 39.80 g/ml). In MTT cytotoxicity analysis Eclipta alba plant extract and AgNPs both display dose-dependent cytotoxicity against triple-negative breast cancer cells (MDA-MB-231), although their IC50 values differ substantially, at 105.80 µg/ml and 77.20 g/ml, respectively. Finally, AgNPs from Eclipta alba tested for anti-leishmanial activity and it showed 91.36 ± 1.05 for promastigotes and 76.62 ± 0.95 for amastigotes at the highest dose of 400 g/ml. Altogether present data showed that Eclipta alba leaf extract actively bonded with silver nanoparticles suppresses the MDA-MB-231 cells growth through high antioxidant characters and anti-leishmanial activity. From together we confirm that Eclipta alba was recommended to a future therapeutic drug and agent to control breast cancer in the clinical level.

4.
J Biotechnol ; 351: 60-73, 2022 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-35500703

RESUMO

The effects of Indole-3-butyric acid (IBA) supplementation in combination with nitrogen limitation on the biomass, biochemical and fatty acid composition of three selenastracean microalgae were studied. In the algae tested, nitrogen deficiency alone resulted in lower biomass output, whereas supplementation with 0.075 mM IBA resulted in increased biomass production on Selenastrum capricornutum (679 mg L-1), Ankistrodesmus falcatus (521 mg L-1) and Kirchneriella obesa (361 mg L-1) than their respective controls. The chlorophyll content of the algae showed a negative correlation with IBA dosage. Whilst it could significantly stimulate carotenoid biosynthesis in S. capricornutum and nitrogen limited (NL) alone, it influenced carotene production in both A. falcatus and K. obesa. Among the treatments, NL+ 0.075 mM IBA markedly increased the total lipid content to 1.2-fold in S. capricornutum, 0.81-fold in A. falcatus and 0.35-fold in K. obesa, with higher lipid productivity than control. NL+ 0.05 mM IBA significantly increased the amount of saturated fatty acids and NL+ 0.075 mM IBA significantly increased the amount of unsaturated fatty acids in all members of the Selenastraceae family under study. Thus, the study promises the importance of Selenastraceae members as a valuable feedstock for various process industries.


Assuntos
Microalgas , Biomassa , Ácidos Graxos , Indóis , Lipídeos , Nitrogênio
5.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-483630

RESUMO

Omicron strain is the latest variant of concern of SarsCov2 virus. The mutations in this strain in the S protein Receptor Binding domain (RBD) enable it to be more transmissible as well as escape neutralizing activity by antibodies in response to vaccine. Thus, Omicron specific strategies are need to counter infection by this strain. We investigated a collection of approved drugs shown to antagonize the binding of native strain RBD to human ACE2, for their ability to antagonize binding to Omicron strain RBD. While most of the drugs the drugs that antagonize binding to native RBD are also active for Omicron RBD but some were inactive, namely drugs that contain iodine are completely inactive against Omicron RBD. Our data strongly indicate that presence of a single iodine molecule in the drug renders it inactive against Omicron strain. Thus, there is molecular specificity of drugs for antagonizing Omicron strain RBD versus native strain RBD of this virus. Such information will pave way for specific drugs for Omicron. A pragmatic message from our data is that the often-used iodine containing mouth wash and rises may be ineffective in antagonizing receptor binding of Omicron strain.

6.
Bol. latinoam. Caribe plantas med. aromát ; 21(1): 1-40, ene. 2022. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1370311

RESUMO

Cancer is an abnormal and uncontrolled growth of cells that spreads through cell division. There are different types of medicines available to treat cancers, but no drug is found to be fully effective and safe for humans. The major problem involved in the cancer treatments is the toxicity of the established drug and their side effects. Medicinal plants are used as folk medicines in Asian and African populations for thousands of years. 60% of the drugs for treating cancer are derived from plants. More than 3000 plants have anticancer activity. The present review aims at the study of a broad spectrum survey of plants having anticancer components for different type of cancers. This article consists of 364 medicinal plants and their different parts as potential Source of Anticancer Agents.


El cáncer es un crecimiento anormal y descontrolado de células que se disemina a través de la división celular. Hay diferentes tipos de medicamentos disponibles para tratar el cáncer, pero no se ha encontrado ningún medicamento que sea completamente efectivo y seguro para los seres humanos. El principal problema involucrado en los tratamientos del cáncer es la toxicidad del fármaco establecido y sus efectos secundarios. Las plantas medicinales se utilizan como medicinas populares en poblaciones asiáticas y africanas durante miles de años. El 60% de los medicamentos para el tratamiento del cáncer se derivan de plantas. Más de 3000 plantas tienen actividad anticancerígena. La presente revisión tiene como objetivo el estudio de un estudio de amplio espectro de plantas que tienen componentes anticancerígenos para diferentes tipos de cánceres. Este artículo consta de 364 plantas medicinales y sus diferentes partes como fuente potencial de agentes anticancerígenos.


Assuntos
Plantas Medicinais/química , Anticarcinógenos/farmacologia , Compostos Fitoquímicos/análise , Linhagem Celular Tumoral/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia
7.
Ayu ; 43(1): 18-25, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-37554414

RESUMO

Background: Water is vital for life as the body uses water in all its cells and tissues to maintain vital functions. Hence, water used for drinking should be free from all types of impurities. Acharya Sushruta has mentioned various water purification methods by keeping it in different types of vessels (silver, copper, and clay) and by adding herbs such as Kataka Beeja (seeds Strychnos potatorum Linn.). With urbanization, there are changes in the lifestyle of individuals and their food habits. Therefore, based on the ease of availability of materials, storage of water needs to be analyzed by simple parameters such as total dissolved solutes (TDS) that comprises inorganic salts such as bicarbonates, sulfates, and chlorides and a small amount of organic matter that is dissolved in water. A high level of TDS indicates water is unfit for consumption and may lead to nausea, vomiting, dizziness, etc., TDS level indicates whether water is suitable for consumption or it requires filtration. Aim: To evaluate and compare the TDS of water kept for 24 h in different vessels made up of silver, copper, clay, plastic, and steel and further with the addition of different herbs like Kataka seeds, Tulsi leaves (Ocimum tenuiflorum Linn.), Nimba leaves (Azadirachta indica A. Juss) separately in different vessels. Materials and methods: The effect of different materials used for storage of water was assessed by evaluating TDS in water samples with the help of a well-calibrated TDS meter, on stored water (100 ml) in different types of vessels (silver, copper, clay, plastic, and steel) and further with the addition of different herbs (10 g) Kataka seeds, Tulsi leaves and Nimba leaves individually and separately, by keeping undisturbed for 24 h. Results: TDS values of the water samples kept for 24 h in different vessels, i.e., silver, copper, plastic, steel, and clay are 372, 429, 436, 445, 628 ppm, respectively, were found. Conclusion: The silver vessel was found to be best in decreasing the TDS value of water among vessels. On evaluating additional effects by adding different herbs, Nimba showed its action best among the storage vessels.

8.
J Forensic Odontostomatol ; 39(1): 16-23, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-34057154

RESUMO

Juvenile crime or delinquency has been increasing at an alarming rate in recent times. In many countries, including India, the minimum age for criminal responsibility is 16 years. The present study aimed to estimate the probability of a south Indian adolescent either being or being older than the legally relevant age of 16 years using Demirjian's tooth formation stages. Orthopantomograms (OPG) of 640 south Indian adolescents (320 boys and 320 girls) aged between 12 and 20 years were retrospectively analyzed. In each OPG, Demirjian's formation stage of the mandibular left third molar was recorded and the data was subjected to statistical analysis. Descriptive and Pearsons correlation statistics were performed. The empirical probabilities were provided relative to the medico-legal question of predicting 16 years of age. The distribution of age throughout the 10th, 25th, 50th, 75th and 90th percentile follows a logical distribution pattern horizontally and vertically. Pearson's correlation statistics showed a strong positive correlation between the Demirjian's stages and age for both sexes. Therefore, it can be concluded that stage "F" can be used to predict the attainment of age equal to or older than 16 years with a probability of 93.9% for boys and 96.6% for girls.


Assuntos
Determinação da Idade pelos Dentes , Dente Serotino , Adolescente , Adulto , Criança , Feminino , Humanos , Índia/epidemiologia , Masculino , Dente Serotino/diagnóstico por imagem , Probabilidade , Estudos Retrospectivos , Adulto Jovem
9.
J Phys Condens Matter ; 31(28): 285802, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-30939461

RESUMO

We report high-precision magnetization ([Formula: see text]), magnetic susceptibility ([Formula: see text]), specific heat (C p (T, H)) and 'zero-field' electrical resistivity, [Formula: see text], data taken on Gd2Te3 single crystal over wide ranges of temperature and magnetic field (H), with either [Formula: see text]-axis or [Formula: see text]-plane. [Formula: see text] and [Formula: see text] unambiguously establish that the b-axis is the easy direction of magnetization whereas any direction in the ac-plane is a hard direction. The [Formula: see text]-type anomaly in 'zero-field' specific heat, C p (T, H = 0), and an abrupt drop in [Formula: see text] (characteristic of the paramagnetic (PM) - antiferromagnetic (AFM) phase transition) are observed at the Néel temperature, [Formula: see text] K. [Formula: see text] and C p (T,H) clearly demonstrate that [Formula: see text] shifts to lower temperatures with increasing H irrespective of whether H points in the easy or hard direction. When [Formula: see text], the [Formula: see text] isotherms at temperatures in the range 2.5 K [Formula: see text] [Formula: see text] K reveal the existence of a field-induced spin-flop (SF) transition at fields 4.0 T [Formula: see text] [Formula: see text] [Formula: see text] 4.5 T. The first principles electronic band structure and density of states calculations, based on the density functional theory, correctly predict an AFM ground state (stabilized primarily by the 4f  Gd3+ - 5p  Te2-- 4f  Gd3+ superexchange interactions) and the observed semi-metallic behavior for the Gd2Te3 compound. Moreover, these calculations yield the values [Formula: see text] [Formula: see text] for the ordered magnetic moment per Gd atom at T = 0, [Formula: see text] mJ mol-1 K-2 for the Sommerfeld coefficient for the electronic specific heat contribution and [Formula: see text] K for the Curie-Weiss temperature, respectively. These theoretical estimates conform well with the corresponding experimental values [Formula: see text] [Formula: see text], [Formula: see text] mJ mol-1 K-2 and [Formula: see text] K.

10.
J Oncol Pharm Pract ; 25(8): 1853-1859, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30616471

RESUMO

Non-small cell lung cancer is a fatal disease associated with high morbidity. It is important to evaluate the effects of treatment on patient's quality of life. Quality of life can be assessed by using EORTC QLQ - C30 and EORTC QLQ - LC 13. Eighty-six patients were enrolled in the study. The patients were divided into four arms as follows: Patients in arm 1 received cisplatin 80 mg/m 2 and gemcitabine 1.25 g/m 2 as infusion separately in isotonic normal saline. Arm 2 received carboplatin 300 mg/m 2 and gemcitabine 1.2 mg/m 2 as infusion separately in 5% dextrose injection. Arm 3 received paclitaxel 100 mg/m 2 as infusion in isotonic normal saline and carboplatin 300 mg/m 2 as infusion in 5% dextrose injection. Arm 4 received pemetrexed 500 mg/m 2 as infusion in isotonic normal saline and carboplatin 300 mg/m 2 as infusion in 5% dextrose injection. The quality of life of the enrolled patients is based on EORTC QLQ - C30 and EORTC QLQ - LC 13 questionnaire. Prevalence of non-small cell lung cancer is more in males, 60-70 years of age. Most of the subjects were from rural areas and had only school-level education. The prevalence of non-small cell lung cancer was more with smokers, ex-smokers and patients with multiple social habits. Comorbidities also increase the risk of non-small cell lung cancer. By analyzing EORTC QLQ - C30 and EORTC QLQ - LC 13 questionnaires, it was found that diarrhea was found to be significant between the groups. Global health status and quality of life are distributed equally among each group. Quality of life and global health status are distributed equally among each sub groups.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Qualidade de Vida , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carboplatina/administração & dosagem , Cisplatino/administração & dosagem , Estudos de Coortes , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Feminino , Humanos , Masculino , Paclitaxel/administração & dosagem , Pemetrexede/administração & dosagem , Estudos Prospectivos , Inquéritos e Questionários , Gencitabina
11.
Bioprocess Biosyst Eng ; 41(2): 281-294, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29177718

RESUMO

The theory of glucose-responsive composite membranes for the planar diffusion and reaction process is extended to a microsphere membrane. The theoretical model of glucose oxidation and hydrogen peroxide production in the chitosan-aliginate microsphere has been discussed in this manuscript for the first time. We have successfully reported an analytical derived methodology utilizing homotopy perturbation to perform the numerical simulation. The influence and sensitive analysis of various parameters on the concentrations of gluconic acid and hydrogen peroxide are also discussed. The theoretical results enable to predict and optimize the performance of enzyme kinetics.


Assuntos
Enzimas Imobilizadas/química , Glucose Oxidase/química , Glucose/química , Membranas Artificiais , Microesferas , Modelos Químicos , Alginatos/química , Quitosana/química , Ácido Glucurônico/química , Ácidos Hexurônicos/química
12.
Environ Monit Assess ; 189(6): 295, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28551884

RESUMO

Spatially explicit approach is essential to prioritise the ecosystems for biodiversity conservation. In the present study, the conservation status of 20 protected areas of the Western Ghats of Kerala, India, was analysed based on long-term changes in forests (1975-1985-1995-2005-2013), landscape level changes in fragmentation and forest fires (2005-2015). This study has shown that a significant forest loss occurred in protected areas before declaration. Idukki is one of the major protected areas which showed a drastic reduction (18.83%) in its forest cover. During 1985-1995, Periyar tiger reserve had lost 24.19 km2 core 3 forest area followed by Peppara (18.54 km2), Parambikulam (17.93 km2), Chimmony (17.71 km2), Peechi-Vazhani (12.31 km2) and Neyyar (11.67 km2). An area of 71.33 km2 of the protected area was affected by fires in 2014. Overall protected area-wise decadal analysis indicates Periyar has the highest number of fire incidences followed by Wayanad, Kurinjimala, Silent Valley and Eravikulam. Disturbances in the form of fires and fragmentation still exist and may have significant conservation threat to flora and fauna. Among protected areas, many are having a probability to go under threat or dynamic stage. Chinnar, Thattekkad and Kurinjimala sanctuaries are representing high levels of vulnerability, or they are near to decline stage. Habitat level monitoring of the anthropogenic disturbances can be efficiently useful for the strategic conservation planning. The present study has provided geospatial database on spatial patterns of deforestation, fragmentation and forest fires in protected areas of Kerala. Conservation prioritization approach based on these parameters will be useful for the strategic planning in the state of Kerala.


Assuntos
Conservação dos Recursos Naturais/métodos , Ecossistema , Monitoramento Ambiental/métodos , Biodiversidade , Desastres , Incêndios , Florestas , Índia , Árvores
13.
J Nanosci Nanotechnol ; 17(1): 398-404, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-29620841

RESUMO

One-dimensional graphitized carbon nanofibers (G-CNFs) were prepared by employing facile electrospinning technique using 10 wt% of polyacrylonitrile (PAN) solution in N,N-dimethyl formamide (DMF) as precursor followed by successive stabilization, carbonization and purification processes. Cobalt sulfide (CoS) nanoparticles were grown onto G-CNFs by hydrothermal method using cobalt chloride and L-cysteine as precursors. The results of X-ray diffraction (XRD) and Raman spectroscopy confirmed the phase formation and degree of graphitization, respectively. Field-emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) images confirmed the morphology, growth and distribution of CoS nanoparticles over G-CNFs (CoS/G-CNFs). The electrochemical studies such as cyclic voltammetry (CV), electrochemical impedance and Tafel polarization revealed that CoS/G-CNFs have lower overpotential, low charge transfer resistance and higher exchange current density for triiodide (I− 3 reduction reaction. The superior electrocat- alytic activity of CoS/G-CNFs than std. Pt is due to combined contribution of interconnected pore structure with high surface area of G-CNFs and excellent electrocatalytic activity of CoS. In addition, the dye sensitized solar cell (DSSC) based on platinum-free CoS/G-CNFs has exhibited higher photo-conversion efficiency (PCE) under a simulated solar light irradiation of 100 mW cm−2 when compared to standard platinum (std. Pt) which is attributed to the synergistic effect of CoS with G-CNFs.

14.
Environ Monit Assess ; 186(12): 8125-40, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25117494

RESUMO

Deforestation in the biosphere reserves, which are key Protected Areas has negative impacts on biodiversity, climate, carbon fluxes and livelihoods. Comprehensive study of deforestation in biosphere reserves is required to assess the impact of the management effectiveness. This article assesses the changes in forest cover in various zones and protected areas of Nilgiri Biosphere Reserve, the first declared biosphere reserve in India which forms part of Western Ghats-a global biodiversity hotspot. In this study, we have mapped the forests from earliest available topographical maps and multi-temporal satellite data spanning from 1920's to 2012 period. Mapping of spatial extent of forest cover, vegetation types and land cover was carried out using visual interpretation technique. A grid cell of 1 km × 1 km was generated for time series change analysis to understand the patterns in spatial distribution of forest cover (1920-1973-1989-1999-2006-2012). The total forest area of biosphere reserve was found to be 5,806.5 km(2) (93.8 % of total geographical area) in 1920. Overall loss of forest cover was estimated as 1,423.6 km(2) (24.5 % of the total forest) with reference to 1920. Among the six Protected Areas, annual deforestation rate of >0.5 was found in Wayanad wildlife sanctuary during 1920-1973. The deforestation in Nilgiri Biosphere Reserve is mainly attributed to conversion of forests to plantations and agriculture along with submergence due to construction of dams during 1920 to 1989. Grid wise analysis indicates that 851 grids have undergone large-scale negative changes of >75 ha of forest loss during 1920-1973 while, only 15 grids have shown >75 ha loss during 1973-1989. Annual net rate of deforestation for the period of 1920 to 1973 was calculated as 0.5 followed by 0.1 for 1973 to 1989. Our analysis shows that there was large-scale deforestation before the declaration of area as biosphere reserve in 1986; however, the deforestation has drastically reduced after the declaration due to high degree of protection, thus indicating the secure future of reserve in the long term under the current forest management practices. The present work will stand as the most up-to-date assessment on the forest cover of the Nilgiri Biosphere Reserve with immediate applications in monitoring and management of forest biodiversity.


Assuntos
Conservação dos Recursos Naturais/tendências , Monitoramento Ambiental , Agricultura Florestal/estatística & dados numéricos , Florestas , Agricultura , Biodiversidade , Clima , Índia
15.
Environ Monit Assess ; 186(5): 3283-96, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24473680

RESUMO

Analyzing the spatial extent and distribution of forest fires is essential for sustainable forest resource management. There is no comprehensive data existing on forest fires on a regular basis in Biosphere Reserves of India. The present work have been carried out to locate and estimate the spatial extent of forest burnt areas using Resourcesat-1 data and fire frequency covering decadal fire events (2004-2013) in Similipal Biosphere Reserve. The anomalous quantity of forest burnt area was recorded during 2009 as 1,014.7 km(2). There was inconsistency in the fire susceptibility across the different vegetation types. The spatial analysis of burnt area shows that an area of 34.2 % of dry deciduous forests, followed by tree savannah, shrub savannah, and grasslands affected by fires in 2013. The analysis based on decadal time scale satellite data reveals that an area of 2,175.9 km(2) (59.6 % of total vegetation cover) has been affected by varied rate of frequency of forest fires. Fire density pattern indicates low count of burnt area patches in 2013 estimated at 1,017 and high count at 1,916 in 2004. An estimate of fire risk area over a decade identifies 12.2 km(2) is experiencing an annual fire damage. Summing the fire frequency data across the grids (each 1 km(2)) indicates 1,211 (26 %) grids are having very high disturbance regimes due to repeated fires in all the 10 years, followed by 711 grids in 9 years and 418 in 8 years and 382 in 7 years. The spatial database offers excellent opportunities to understand the ecological impact of fires on biodiversity and is helpful in formulating conservation action plans.


Assuntos
Monitoramento Ambiental/métodos , Incêndios , Sistemas de Informação Geográfica , Tecnologia de Sensoriamento Remoto , Árvores , Biodiversidade , Conservação dos Recursos Naturais , Bases de Dados Factuais , Índia
16.
Saudi J Biol Sci ; 20(1): 93-103, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23961226

RESUMO

Synthesis and hardening of a new exoskeleton are essential to the arthropod molting process. The present study emphasizes the variations in the levels of hemolymph total free sugars, hepatopancreas glycogen and cuticular proteins during the molting stages of Portunus pelagicus. It also reports the effect of short-term starvation conditions on the biochemical constituents of the hemolymph. Intermolt crabs were subjected to 6 days of starvation and hemolymph samples were taken. Standard biochemical procedures were followed toward the quantification of total proteins, total free sugars and total lipids. The total free sugar level in the hemolymph of P. pelagicus was observed to increase during early premolt D0 (3.108 ± 0.032 g/ml) and a gradual decrease till late postmolt B stage (0.552 ± 0.124 g/ml), suggesting the need for total free sugars to provide energy for the apolysis process. Increase in the levels of hepatopancreas glycogen was observed from 1225 ± 0.04 µg/mg in early premolt D0 to 1700 ± 0.3 µg/mg in late premolt D2-3. This is in correlation with the decreased levels of free sugars during premolt stages, suggesting an increase in the storage of glycogen reserves in the hepatopancreas. Cuticular proteins increased during stage B (2.702 ± 0.093 g/ml) and stage C (3.065 ± 0.012 g/ml), indicating exoskeleton hardening and mineralization. Results of the starvation studies clearly showed a steady decline in the level of total free sugars till day 6 (0.099 ± 0.00 g/ml) when compared to the control (8.646 ± 0.08 g/ml). Gradual decrease of total lipids was also observed from the first day of the experiment (6.088 ± 2.44 g/ml) to the last day of the study (0.401 ± 0.20 g/ml) which was 85% lesser than the control (8.450 ± 0.49 g/ml)suggesting the efficient usage of total sugars to consolidate the loss of energy reserves during starvation. The knowledge of Molt-cycle events can be used as a tool for the evaluation of the developmental state providing a morphological reference system for physiological and biochemical studies related to crab aquaculture. Starvation studies enlightens that increasing carbohydrate levels in crab feed together with good protein content could alleviate the natural effects of starvation, improve farm productivity and reduce the deleterious impact of nitrogen pollution generated by rich-protein feeds used in crab farming.

17.
Hum Exp Toxicol ; 32(7): 706-20, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23155198

RESUMO

Polychlorinated biphenyls (PCBs) comprise a ubiquitous class of toxic substances associated with carcinogenic and tumor-promoting effects as well as neurotoxic properties. Reactive oxygen species, which is produced from PCBs, alters blood-brain barrier (BBB) integrity, which is paralleled by cytoskeletal rearrangements and redistribution and disappearance of tight junction proteins (TJPs) like claudin-5 and occludin. Quercetin, a potent antioxidant present in onion and other vegetables, appears to protect brain cells against oxidative stress, a tissue-damaging process associated with Alzheimer's and other neurodegenerative disorders. The aim of this study is to analyze the role of quercetin on oxidative stress markers and transcription of transmembrane and cytoplasmic accessory TJPs on cerebrum, cerebellum and hippocampus of female rats exposed to PCBs. Rats were divided into the following four groups. Group I: received only vehicle (corn oil) intraperitoneally (i.p.); group II: received Aroclor 1254 at a dose of 2 mg/kg body weight (bwt)/day (i.p); group III: received Aroclor 1254 (i.p.) and simultaneously quercetin 50 mg/kg bwt/day through gavage and group IV: received quercetin alone gavage. From the experiment, the levels of hydrogen peroxide, lipid peroxidation and thiobarbituric acid reactive substances were observed to increase significantly in cerebrum, cerebellum and hippocampus as 50%, 25% and 20%, respectively, after exposure to PCB, and the messenger RNA expression of TJP in rats exposed to PCBs is decreased and is retrieved to the normal level simultaneously in quercetin-treated rats. Hence, quercetin can be used as a preventive medicine to PCBs exposure and prevents neurodegenerative disorders.


Assuntos
Encéfalo/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Fármacos Neuroprotetores/farmacologia , Bifenilos Policlorados/toxicidade , Quercetina/farmacologia , Animais , Encéfalo/metabolismo , Feminino , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Proteínas de Junções Íntimas/genética
18.
Biotechnol Prog ; 27(5): 1464-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21710608

RESUMO

Biosynthesis of nanoparticles using microorganisms has attracted a lot of attention in recent years as this route has the potential to lead to synthesis of monodisperse nanoparticles. Here, we report the intracellular synthesis of stable lead sulfide nanoparticles by a marine yeast, Rhodosporidium diobovatum. The PbS nanoparticles were characterized by UV-visible absorption spectroscopy, X-ray diffraction (XRD) and energy dispersive atomic spectroscopy (EDAX). UV-visible absorption scan revealed a peak at 320 nm, a characteristic of the nanosize range. XRD confirmed the presence of PbS nanoparticles of cubic structure. Crystallite size as determined from transmission electron microscopy was found to be in the range of 2-5 nm. Elemental analysis by EDAX revealed the presence of particles composed of lead and sulfur in a 1:2 ratio indicating that PbS nanoparticles were capped by a sulfur-rich peptide. A quantitative study of lead uptake through atomic absorption spectrometry revealed that 55% of lead in the medium was accumulated in the exponential phase, whereas a further 35% was accumulated in the stationary phase; thus, the overall recovery of PbS nanoparticles was 90%. The lead-exposed yeast displayed a marked increase (280% over the control) in nonprotein thiols in the stationary phase.


Assuntos
Basidiomycota/metabolismo , Biologia Marinha , Nanopartículas Metálicas , Sulfetos/síntese química , Chumbo , Microscopia Eletrônica de Transmissão , Espectrofotometria Ultravioleta , Difração de Raios X
19.
Indian J Physiol Pharmacol ; 55(4): 357-63, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-23362729

RESUMO

Though prehypertension has recently been considered as a risk factor for cardiovascular accidents, the pathophysiological mechanism that causes the development of prehypertension in normotensive subjects has not been fully elucidated. Therefore, the present study was conducted to assess the sympathovagal imbalance in prehypertensives and normotensives by spectral analysis of heart rate variability (HRV) to understand the nature of change in autonomic balance in this dysfunction. Body mass index (BMI), waist-hip ratio (WHR), basal heart rate (BHR), blood pressure (BP), rate-pressure product (RPP) and spectral indices of HRV such as total power (TP), normalized low frequency power (LFnu), normalized high frequency power (HFnu), ratio of low frequency power to high frequency power (LF-HF ratio), mean heart rate (mean RR), square root of the mean squared differences of successive normal to normal intervals; (RMSSD), the number of interval differences of successive NN intervals greater than 50 ms (NN50) and the proportion derived by dividing NN50 by the total number of NN intervals (pNN50) were assessed in two groups of young subjects: normotensives (n=68) and prehypertensives (n=66). Sympathovagal balance (SVB) was analyzed and correlated with BMI, WHR, BHR, BP and RPP in both the groups. It was observed that autonomic imbalance in prehypertensives was due to increase in both sympathetic activity and vagal inhibition. LF-HF ratio, the sensitive indicator of SVB was significantly correlated with BMI, WHR, BHR, BP and RPP in prehypertensive subjects. It was concluded that vagal inhibition might be important in the critical alteration of sympathovagal balance in the development of prehypertension in young normotensive subjects.


Assuntos
Frequência Cardíaca/fisiologia , Pré-Hipertensão/fisiopatologia , Sistema Nervoso Simpático/fisiologia , Nervo Vago/fisiologia , Adulto , Humanos
20.
Bioinformation ; 1(7): 269-75, 2006 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-17597906

RESUMO

Autism is a developmental disability causing learning and memory disorder. The heart of the search for a cure for this syndrome is the need to understand dendrite branch patterning, a process crucial for proper synaptic transmission. Due to the association of snapin with the SNARE complex and its role in synaptic transmission it is reported as a potential drug target for autism therapies. We wish to impart the noesis of the 3D structure of the snapin protein, and in this chase we predict the native structure from its sequence of amino acid residues using the classical Comparative protein structure modeling methods. The predicted protein model can be of great assistance in understanding the structural insights, which is necessary to understand the protein function. Understanding the interactions between snapin and SNARE complex is crucial in studying its role in the neurotransmitter release process. We also presented a computational model that shows the interaction between the snapin and SNAP-25 protein, a part of the larger SNARE complex.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...