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1.
Environ Sci Pollut Res Int ; 30(35): 83439-83451, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37344715

RESUMO

The perception of spatio-temporal variability of winter precipitation covering dominant water resources and environment over Kashmir Himalaya is a pre-eminent perspective under current social interests. The main objectives of the study are, firstly, to unriddle the whole (1980-2020) and post-2000 trend in the winter season precipitation (WP), frequency of low-pressure systems (Lp-S), and western disturbances (WDs) to understand the footprints of climate change over the region; secondly, to evaluate the spatio-temporal variability of winter precipitation under the dominance of global teleconnection indices, using both station and reanalysis datasets. Modified Mann-Kendell test and a linear regression model were utilized to extract the trend and significance in WP, Lp-S, and WDs. The results reveal that WP shows an insignificant decreasing trend (1980-2020), with an increasing trend post-2000, while a decreasing trend is seen during post-2000 in the frequency of Lp-S and WDs. The contribution of WP to annual precipitation shows decadal variability with a decreasing trend post-2000. The anatomy of winter extreme precipitation days has shown a decreasing trend (1980-2020), with a robust coupled increasing trend with WP post-2000. The dynamics of ten severe WD-based extreme precipitation events show that a cyclonic circulation and trough connects the Arabian Sea and the Himalayas, bringing additional moisture to the study region and resulting in extreme precipitation. The cogency of global teleconnections on the variability of WP shows that a pattern with positive phase of NAO, ENSO, and a negative phase in Siberian high intensifies the WD-based precipitation. The study discovers its applicability for the regional forecast system in predicting the winters.


Assuntos
Tempestades Ciclônicas , Recursos Hídricos , Estações do Ano , Mudança Climática , Modelos Lineares
2.
ACS Omega ; 8(2): 2227-2236, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36687096

RESUMO

Dementia or the loss of cognitive functioning is one of the major health issues in elderly people. Alzheimer's disease (AD) is one of the common forms of dementia. Treatment chiefly involves the use of acetylcholinesterase (AChE) inhibitors in AD. However, oxidative stress has also been found to be involved in the proliferation of the disease. Magnoflorine is one of the active compounds of Coptidis Rhizoma and has high anti-oxidative properties. Active principle-loaded nanoparticles have shown increased efficiency for neurodegenerative diseases due to their ability to cross the blood-brain barrier more easily. An in vitro study involving magnoflorine-loaded chitosan collagen nanocapsules (MF-CCNc) has shown them to possess inhibitory effects against oxidative stress and to some extent on AChE as well. In the current study, both nootropic and anti-amnesic effects of magnoflorine and MF-CCNc on scopolamine-induced amnesia in rats were evaluated. The treatment was done intraperitoneally (i.p.) once daily for 17 consecutive days with MF-CCNc (0.25, 0.5, and 1 mg), magnoflorine (1 mg), and donepezil (1 mg). To induce amnesia, hence, cognitive deficit rats were induced with scopolamine (1 mg/kg) daily for the last 9 days. Novel object recognition (NOR) and elevated plus maze (EPM) behavioral analysis were done to assess memory functioning. Hippocampal tissues were extracted to study the effect on biochemicals (AChE, MDA, SOD, and CAT), pro-inflammatory cytokines (IL-1ß, IL-6, and TNF-α), and immunohistochemistry (brain-derived neurotrophic factor (BDNF) and DCX). MF-CCNc showed memory-enhancing effects in nootropic as well as chronic scopolamine-treated rats in NOR and an increase in inflexion ratio in EPM. MF-CCNc reduced the levels of AChE and MDA while increasing SOD and CAT levels in the hippocampus. MF-CCNc further lowered the levels of pro-inflammatory cytokines IL-1ß, IL-6, and TNF-α. These nanocapsules further increased the expression of BDNF and DCX that are necessary for adult neurogenesis. From the research findings, it can be concluded that MF-CCNc has high anti-amnesic properties and could be a promising candidate for the treatment of AD.

3.
Environ Sci Pollut Res Int ; 29(47): 71593-71606, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35604611

RESUMO

The association of hydrological extremes to a specific season provides a perception that the extraction of dominant patterns of seasonal precipitation variability can be useful to identify the hidden pathways of oceanic-atmospheric mechanisms behind these extremes. The native objective of this study is to find the empirical orthogonal function (EOF) patterns of seasonal precipitation using daily gridded precipitation data over the study region. The spatio-temporal variability of monthly precipitation reveals that over the entire study region precipitation occurs throughout the year with less in November and more in August. We found two dominant EOF patterns of precipitation for summer (JJA) and fall (SON) that have captured all the observed floods from 1901 to 2018. The PC of the dominant pattern of summer season precipitation variability (EOF3) shows a significant negative correlation with the El Niño-Southern Oscillation (ENSO) index (Niño 3.4) depicting that global teleconnection influences the variability of JJA precipitation over this region, while the PC of the dominant pattern of SON season precipitation variability (EOF2) has captured the 2014 deadliest flood which is positively correlated with ENSO at < 5% significance level and can be considered a positive domain response of SON precipitation to the variability of SST over the tropical Pacific Ocean (ENSO). The study will find its applicability in predicting the response of hydrological extremes to global teleconnections and hence can be applied in disaster mitigation and decision-making for the water resource management over the study region.


Assuntos
El Niño Oscilação Sul , Hidrologia , Oceanos e Mares , Oceano Pacífico , Estações do Ano
4.
ACS Omega ; 7(8): 6472-6480, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35252643

RESUMO

Neurodegeneration is one of the most common diseases in the aged population, characterized by the loss in the function of neuronal cells and their ultimate death. One of the common features in the progression of this type of diseases is the oxidative stress. Drugs which are currently being used have been found to show lateral side effects, which is partly due to their inefficiency to cross blood-brain barrier. Nanoencapsulation of bioactive compounds is a profound approach in this direction and has become a method of choice nowadays. This study involved the evaluation of the anti-oxidative properties of magnoflorine (MF), which is an aporphine quaternary alkaloid, and synthesis of MF-loaded chitosan-collagen nanocapsules (MF-CCNc) for its better efficacy as a potent anti-oxidant. Physiochemical characterization of the synthesized nanocapsules was done by using dynamic light scattering and transmission electron microscopy. It revealed that the synthesized nanocapsules are of small size range, as small as 12 ± 2 nm, and are more or less of spherical shape. Sustained release was shown by MF in the in vitro drug release studies. Both MF and MF-CCNc were found to have good anti-oxidant potential with IC50 < 25 µg/mL. No major cytotoxicity was shown by the synthesized nanocapsules on SH-SY5Y cells. In silico anti-acetylcholinesterase (AChE) studies were also done, and they revealed that MF can be a potent inhibitor of AChE.

5.
Environ Sci Pollut Res Int ; 28(39): 55796-55809, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34142325

RESUMO

The perception of spatio-temporal variability of drought is important in concerning the food security of a country. The native aim of this study is to extract the spatio-temporal variability of drought over India with implications on agriculture. We have opted for SPI-3 as the primary index for drought quantification. The spatio-temporal variability of SPI-3 is evaluated through empirical orthogonal functional (EOF) analysis to extract the prominent patterns of drought variability over the study region. The first two dominant patterns of SPI-3 explain (38%) the total variability and are mainly influenced by global teleconnections. The EOF patterns while subjected to spectrum analysis depict that the first mode shows 7.7 years of cycle and the second mode shows 2.6 years of the cycle. On seeing the interference of El Nino Southern Oscillation (ENSO) on drought, we found that drought years are mainly influenced by ENSO with the same periodicity (2-7 years/cycle) as that of EOF patterns. The dynamics of drought show that the persistence of high pressure along East and West Asia during drought years has declined the monsoon activity over India leading to a shortfall of rainfall in monsoon months. On the other hand, we have found that the drought years have drawn implications on agricultural production by stifling the total annual production of most of the drought years. This research would have a wide range of applications in forecasting extreme events in India, allowing for better preparation and management of the water resource system during droughts.


Assuntos
Secas , Meteorologia , Agricultura , Ásia , Índia
6.
RSC Adv ; 11(40): 24900-24916, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35481013

RESUMO

Use of plant extracts for the synthesis of various metal nanoparticles has gained much importance recently because it is a simple, less hazardous, conservative and cost-effective method. In this research work, platinum nanoparticles were synthesized by treating platinum ions with the leaf extract of Psidium guajava and their structural properties were studied using various characterization techniques. The formation of platinum nanoparticles was confirmed by the disappearance of the absorbance peak at 261 nm in UV-visible spectra. The results of gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FT-IR) analysis showed functional moieties responsible for bio-reduction of metal ions and stabilization of platinum nanoparticles. The use of dynamic light scattering (DLS) imaging techniques confirmed the formation of stable monodispersed platinum nanoparticles showing a zeta potential of -23.4 mV. The morphological examination using high resolution transmission electron microscopy (HR-TEM) and Scanning electron microscopy (SEM) confirmed the formation of spherical platinum nanoparticles with an average diameter of 113.2 nm. X-ray powder diffraction (XRD) techniques showed the crystalline nature of biosynthesized platinum nanoparticles with a face-centered cubic structure. The results of energy-dispersive X-ray spectroscopy (EDAX) showed 100% platinum content by weight confirming the purity of the sample. The cytotoxic effect of biosynthesized platinum nanoparticles assessed in a breast cancer (MCF-7) cell-line by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, revealed an IC50 of 167.2 µg ml-1. The results of a wound healing assay showed that treatment with platinum nanoparticles induced an anti-migratory effect on MCF-7 cells. In the cell cycle phase distribution, treatment with platinum nanoparticles inhibited cell proliferation as determined by flow cytometry with PI staining. Significant cell cycle arrest was detected at the G0/G1 phase with a notable decrease in the distribution of cells in the S and G2/M phases. The anti-bacterial activity of bio-synthesized platinum nanoparticles was evaluated against four pathogenic bacteria i.e. B. cereus (Gram positive), P. aeruginosa (Gram negative), K. pneumonia (Gram negative) and E. coli (Gram negative). The biosynthesized platinum nanoparticles were found to show dose-dependent inhibition against pathogenic bacteria with a significant effect on Gram-negative bacteria compared to Gram-positive bacteria. This synergistic blend of green and simplistic synthesis coupled with anti-proliferative and anti-bacterial properties makes these biogenic nanoparticles suitable in nanomedicine.

7.
J Microencapsul ; 37(2): 160-169, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31916886

RESUMO

The aim of this study was to develop levosulpiride-loaded solid lipid nanoparticles (SLNs) with enhanced solubilisation and bioavailability. The levosulpiride loaded-SLNs were composed of levosulpiride, stearic acid, and tween 80 in their respective weight ratios of (1, 5, and 1.5 mg) dissolved in 1 ml distilled water. Physicochemical properties of the SLNs such as particle size, shape, crystallinity, and chemical interaction were evaluated. Further, the in vitro drug dissolution, pharmacokinetic and stability studies of the SLNs were performed. The SLNs were rounded shaped stable nanoparticles with average diameter of 200 nm. They demonstrate 1.5- and 3-fold better drug dissolution when compared with the commercial product and levosulpiride powder, respectively. The SLNs enhanced the bioavailability of levosulpiride 3 times and 7 times, respectively, when compared with the commercial product and levosulpiride powder. It can be concluded that SLNs are capable to improve the dissolution and bioavailability of levosulpiride, even more than the commercial product.


Assuntos
Portadores de Fármacos , Lipídeos , Nanopartículas/química , Sulpirida/análogos & derivados , Animais , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Lipídeos/química , Lipídeos/farmacocinética , Lipídeos/farmacologia , Masculino , Ratos , Ratos Sprague-Dawley , Sulpirida/química , Sulpirida/farmacocinética , Sulpirida/farmacologia
8.
J Ayub Med Coll Abbottabad ; 15(2): 28-30, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14552244

RESUMO

BACKGROUND: Worm infestation is a major problem in children from developing countries due to bad hygienic conditions. It produces nutritional deficiencies and anaemia in children, especially when hookworm infestation is present. METHODS: This cross-sectional study deals with investigation of the frequency of intestinal parasitic infestation in children between the ages 5-12 years. A total of 283 subjects were tested and screened for different intestinal parasites at of Department of Physiology, Ayub Medical College, Abbottabad. Negative cases were re-examined and if found free of intestinal pathogenic parasites were labelled as negative. RESULTS: Of the 283 children examined, 230 tested positive for various intestinal parasites. The frequency of helminthic infestation was found to be above 81%. There were 8 different species of helminths and protozoa found in the specimens. By far the highest frequency of 48% was noted for Ascaris lumbricoides while 6.9% (16 cases) of the specimens examined had mixed infestation. The mean Haemoglobin (Hb) level was found to be 9.82 g/dl in males and 9.0 g/dl in females. Virtually no Hookworm infestation was found which may be the reason of not so low Hb level of the subjects. CONCLUSIONS: A very high percentage (81%) of children from suburbs of Abbottabad have intestinal worm infestation and majority of them (48% of positive cases) have Ascaris lumbricoides. Children were not very severely anaemic because of virtually no hook worm cases.


Assuntos
Ascaríase/epidemiologia , Helmintíase/epidemiologia , Infecções por Uncinaria/epidemiologia , Enteropatias Parasitárias/epidemiologia , Distribuição por Idade , Animais , Ascaríase/diagnóstico , Criança , Pré-Escolar , Estudos Transversais , Países em Desenvolvimento , Feminino , Seguimentos , Helmintíase/diagnóstico , Infecções por Uncinaria/diagnóstico , Humanos , Enteropatias Parasitárias/diagnóstico , Masculino , Paquistão/epidemiologia , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Distribuição por Sexo , População Urbana
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