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1.
Cureus ; 15(9): e45797, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37881378

RESUMO

Bilateral internal carotid artery (ICA) dissection on heavy weight lifting is a very rare cause of stroke in young patients. Arterial dissection is due to a tear in the intima and internal elastic lamina which leads to extravasation of blood into the media and subintimal plane. Clinical diagnosis of carotid artery dissection is difficult with common clinical presentations like headache and neck pain. Here we present a case of a 40-year-old young man who presented to us (tertiary referral center) with headache and quadriparesis. MRI brain showed multiple acute infarcts in bilateral centrum semiovale extending up to frontal periventricular white matter with few tiny foci in bilateral medial temporal and left gangliocapsular regions and CT cerebral angiography showed bilateral ICA dissection. He was treated with low molecular weight heparin and was discharged for follow-up with regular physiotherapy.

2.
Ecotoxicology ; 30(4): 719-732, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33797020

RESUMO

TiO2 nano particles (NPs) are one of the most produced nanoparticles in the world which are increasingly being released in to the soil. Soils are exposed to various level of concentration of TiO2 NPs, which has raised concern over the adverse influence on soil microbial community, in turn on ecosystem functions. Although, increasing number of studies on ecotoxicological effect of TiO2 NPs are coming up recently, however, a common conscience has yet to be reached regarding the impact of TiO2 NPs on soil microbial community and processes. Moreover, very few studies have targeted soil enzymes which are being considered as sensitive indicator of soil health. Therefore, the present study has been carried out to estimate the ecotoxicological effect of various doses of TiO2 NPs (5, 10, 20, 40, 80, 100 mg kg-1 soil) on different soil enzymes and microbial community structure. Results revealed that soil enzyme activities and microbial biomass had a uniform trend where the value increased up to the dose of 20 mg TiO2 NPs kg-1 soil and there onwards reduced drastically up to 100 mg TiO2 NPs kg-1 soil dose. On the contrary, soil respiration and metabolic quotient kept increasing up to 100 mg TiO2 NPs kg-1 soil dose indicating sub-lethal stress on microbial community. Nevertheless, the structure of microbial community had slightly different trend where the biomass of total phospho lipid fatty acid (PLFA), Gram positive, Gram negative bacteria, fungi, actinomyctetes and anaerobes were found to be increased up to dose of 80 mg TiO2 NPs kg-1 soil, but, significantly declined at 100 mg TiO2 NPs kg-1 soil dose. Furthermore, temperature effect on TiO2 NPs toxicity had exhibited a less negative impact at 40 °C rather than at 25 °C. In addition alteration index (AI3), an integrated indicator of C, N, P cycling of soils as well as a well-documented indicator of soil pollution, has been found to be regulated by soil respiration, clay content, anaerobe and eukaryote for AI3-Acid Phos. and by fungi to bacteria ratio, soil respiration, microbial biomass and Gram positive bacteria for AI3-Alk. Phos. Overall, the study provided valuable information regarding ecotoxicological impact of environmentally relevant concentrations of TiO2 NPs in clay loam soils as well as improved our perception regarding the impact of NPs on soil functioning.


Assuntos
Microbiota , Solo , Biomassa , Microbiologia do Solo , Titânio/toxicidade
3.
Environ Monit Assess ; 193(4): 186, 2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33713208

RESUMO

The present research was conducted to study the potential of cotton for the remediation of soils contaminated with Cd, to understand the biochemical basis of its tolerance to, and to investigate the plant-microbe interaction in the rhizosphere for enhancement of phytoextraction of Cd. Cotton (Bt RCH-2) was exposed to four Cd levels (0, 50, 100, and 200 mg/kg soil) in a completely randomised design and found that the plant could tolerate up to 200 mg/kg soil. Cd stress increased the total phenol, proline, and free amino acid contents in the plant leaf tissue compared with control but inhibited basal soil respiration, fluorescein diacetate hydrolysis, and activities of several enzymes viz. dehydrogenase, phosphatases, and ß-glucosidase in the soil over control. The concentration of Cd in the shoot was less than the critical concentration of 100 µg/g dry weight, and bioconcentration and translocation factors were < 1 to classify the plant as a hyperaccumulator of Cd. This was further confirmed by another experiment in which the cotton plant was exposed various higher levels of Cd (200, 400, 600, 800, and 1000 mg/kg soil). Though the concentration of Cd in the shoot was > 100 µg g -1dw beyond 600 mg Cd/kg soil, the bioconcentration and translocation factors were < 1. The study on plant-microbe (Aspergillus awamori) interaction revealed that the fungus did not affect the absorption of Cd by cotton. It was concluded that the cotton was classified as an excluder of Cd and therefore could be suitable for the phytostabilization of Cd-contaminated soils.


Assuntos
Cádmio , Poluentes do Solo , Aspergillus , Biodegradação Ambiental , Cádmio/análise , Monitoramento Ambiental , Gossypium , Solo , Poluentes do Solo/análise
4.
Artigo em Inglês | MEDLINE | ID: mdl-33624237

RESUMO

Two experiments were conducted to determine the cotton plant's tolerance to Pb and its remediation potential. In the first experiment, the phytoremediation potential was determined by exposing the plant to four levels of Pb (0, 500, 750, and 1000 mg kg-1). The cotton plant exhibited an excellent tolerance index at Pb 1000 mg kg-1 (root 78.65% and shoot 93.08%) and lower grade of growth inhibition (root 21.35% and shoot 6.92%). Pb stress resulted in higher leakage of electrolytes and increased the synthesis of higher proline, total phenol, and free amino acid contents to mitigate stress. The plant could not meet the criteria of a hyperaccumulator of Pb. The concentration of Pb in the shoot was a mere 96 µg g-1 dry wt (< the critical judging concentration of 1000 µg g-1 dry wt), and bioconcentration and translocation factors were <1. The study established that cotton exhibited an exclusion mechanism of Pb. Further, the translocation efficiency (TE %) was very low, i.e., <50% (ranged from 49% at 500 mg kg-1 to 42% at 1000 mg kg -1), and the % of Pb removed by the crop was too little (on an average 0.1%). Pb inhibited the dehydrogenase activity (DHA) by 76%, fluorescein diacetate (FDA) hydrolysis by 60%, and ß-glucosidase activity by 20%. However, applied Pb increased the population of actinomycetes by 3.21 times, but significantly decreased heterotrophic bacteria by 3.40 times and N2 fixers by over 53% over control. In the second experiment, the plant was exposed to very high Pb (0, 1000, 1500, 2000, 2500, and 3000 mg kg -1) to determine the concentration up to which the plant will survive. The investigation revealed that plants could survive up to Pb 3000 mg kg-1. It confirmed the first experiment in the tolerance index, grade of growth inhibition, bioconcentration factor, translocation factor, and partitioning of Pb. Therefore, it was concluded that the cotton plant was an excluder of Pb and could be effectively cultivated for the phytostabilization of soils polluted with Pb.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33625699

RESUMO

Open field burning of crop residue causes severe air pollution and greenhouse gas emission contributing to global warming. In order to seek an alternative, the current study was initiated to explore the prospective of lignocellulolytic microbes to expedite in situ decomposition of crop residues. Field trials on farmers' field were conducted in the state of Haryana and Maharashtra, to target the burning of rice and wheat residue and sugarcane trash, respectively. A comparative study among crop residue removal (CRR), crop residue burning (CRB) and in situ decomposition of crop residues (IND) revealed that IND of rice and wheat residues took 30 days whereas IND of sugarcane trash took 45 days. The decomposition status was assessed by determining the initial and final lignin to cellulose ratio which increased significantly from 0.23 to 0.25, 0.21 to 0.23 and 0.24 to 0.27 for rice, wheat residues and sugarcane trash, respectively. No yield loss was noticed in IND for both rice-wheat system and sugarcane-based system; rather IND showed relatively better crop yield as well as soil health parameters than CRB and CRR. Furthermore, the environmental impact assessment of residue burning indicated a substantial loss of nutrients (28-31, 23-25 and 51-77 kg ha-1 of N+P2O5+K2O for rice, wheat and sugarcane residue) as well as the emission of pollutants to the atmosphere. However, more field trials, as well as refinement of the technology, are warranted to validate and establish the positive potential of in situ decomposition of crop residue to make it a successful solution against the crop residue burning.

6.
Front Microbiol ; 12: 758144, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35140690

RESUMO

A cadmium (Cd)-tolerant bacterium Ochrobactrum intermedium BB12 was isolated from sewage waste collected from the municipal sewage dumping site of Bhopal, India. The bacterium showed multiple heavy metal tolerance ability and had the highest minimum inhibitory concentration of 150 mg L-1 of Cd. Growth kinetics, biosorption, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy studies on BB12 in the presence of Cd suggested biosorption as primary mode of interaction. SEM and TEM studies revealed surface deposition of Cd. FTIR spectra indicated nitrogen atom in exopolysaccharides secreted by BB12 to be the main site for Cd attachment. The potential of BB12 to alleviate the impact of Cd toxicity in spinach plants (Spinacia oleracea L.) var. F1-MULAYAM grown in the soil containing Cd at 25, 50, and 75 mg kg-1 was evaluated. Without bacterial inoculation, plants showed delayed germination, decrease in the chlorophyll content, and stunted growth at 50 and 75 mg kg-1 Cd content. Bacterial inoculation, however, resulted in the early germination, increased chlorophyll, and increase in shoot (28.33%) and root fresh weight (72.60%) at 50 mg kg-1 of Cd concentration after 75 days of sowing. Due to bacterial inoculation, elevated proline accumulation and lowered down superoxide dismutase (SOD) enzyme activity was observed in the Cd-stressed plants. The isolate BB12 was capable of alleviating Cd from the soil by biosorption as evident from significant reduction in the uptake/translocation and bioaccumulation of Cd in bacteria itself and in the plant parts of treated spinach. Potential PGP prospects and heavy metal bioremediation capability of BB12 can make the environmental application of the organism a promising approach to reduce Cd toxicity in the crops grown in metal-contaminated soils.

7.
J Environ Manage ; 244: 144-153, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31121501

RESUMO

To accelerate the process of decomposition using consortia of thermophilic ligno-cellulolytic fungi, different crop residues viz. sorghum (SG), soybean (SS), maize (MS), sugarcane (SC), cotton (CS) and pigeon pea (PS) with a varied C:N ratio and sawdust (SD) having high lignin content were collected and used for decomposition process. Compost quality assessed by evaluating different maturity and stability indices at five succeeding stages [first mesophilic (M1), thermophilic (T), second mesophilic (M2), cooling (C) and humification (H)]. A significant reduction was observed in the C:N ratio, biodegradability index, nitrification index, ratio of water-soluble carbon to organic nitrogen (WSC/Org.N) with an increase in concomitant over time while Ash (%), organic matter loss (%), CEC/TOC ratio, cellulose biodegradation ratio (BR) and lignin/cellulose ratio were significantly increased with time. By correlation study, biodegradability index (BI) and fluorescein diacetate (FDA) hydrolysis emerged as the most suitable compost maturity and stability parameters, respectively. Principal component analysis (PCA) results confirmed that BI, BR, WSC/Org. N and FDA can be regarded as key indicators for assessing compost quality. Our findings conclude that fungal consortia of Tricoderma viride, Rhizomucor pusillus, Aspergillus awamori and Aspergillus flavus can accelerate decomposition time from 8 to 12 months (which is normal farming practice) to 120 days.


Assuntos
Solo , Gerenciamento de Resíduos , Carbono , Fungos , Nitrogênio , Temperatura
8.
Mol Pharmacol ; 75(3): 447-53, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19047479

RESUMO

Dopamine activates phospholipase C in discrete regions of the mammalian brain, and this action is believed to be mediated through a D(1)-like receptor. Although multiple lines of evidence exclude a role for the D(1) subtype of D(1)-like receptors in the phosphoinositide response, the D(5) subtype has not been similarly examined. Here, mice lacking D(5) dopamine receptors were tested for dopamine agonist-induced phosphoinositide signaling both in vitro and in vivo. The results show that hippocampal, cortical, and striatal tissues of D(5) receptor knockout mice significantly or completely lost the ability to produce inositol phosphate or diacylglycerol messengers after stimulation with dopamine or several selective D(1)-like receptor agonists. Moreover, endogenous inositol-1,4,5-trisphosphate stimulation by the phospholipase C-selective D(1)-like agonist 3-methyl-6-chloro-7,8-dihydroxy-1-[3methylphenyl]-2,3,4,5-tetrahydro-1H-3-benzazepine (SKF83959) was robust in wild-type animals but undetectable in the D(5) receptor mutants. Hence, D(5) receptors are required for dopamine and selective D(1)-like agonists to induce phospholipase C-mediated phosphoinositide signaling in the mammalian brain.


Assuntos
Agonistas de Dopamina/farmacologia , Receptores de Dopamina D5/agonistas , Receptores de Dopamina D5/fisiologia , Fosfolipases Tipo C/metabolismo , Animais , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Dopamina D5/deficiência , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
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