Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 71
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Curr Top Med Chem ; 23(15): 1426-1447, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37638604

RESUMO

Two-dimensional (2D) nanomaterials (NMs) have diverse mechanical, chemical and optical properties due to which they have received a lot of attention in various fields such as biosensors, imaging, tissue engineering, drug delivery, etc. A thorough understanding of the synthetic procedure, physical properties and electrochemical properties of 2D materials will be quite useful in the development of novel and high-efficient electrocatalysts for the electroanalytical application of our interest. This review article summarises the synthesis and application of graphene, graphitic carbon nitride, transition metal dichalcogenides and phosphorene for electrochemical biosensing, drug delivery application and environmental monitoring. Numerous synthetic approaches which have been adopted to synthesize the 2D materials have been covered and discussed. Also, the reasons behind the catalytic activity of various types of 2D materials and their application as electrode modifier for the development of an efficient biosensor for the point-of-care analysis of biomolecule and drug delivery and environmental monitoring have been discussed in detail. This review article will give valuable information and future insights to the researchers working in the field of biosensor, drug delivery and environmental monitoring. We anticipate that this review may be of significance for the field to understand the properties as well as the electroanalytical applications of 2D materials, especially in biosensing, drug and environmental monitoring.


Assuntos
Monitoramento Ambiental , Nanoestruturas , Sistemas de Liberação de Medicamentos , Eletrodos , Sistemas Automatizados de Assistência Junto ao Leito
2.
Biosensors (Basel) ; 13(7)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37504138

RESUMO

A monolayer of boron known as borophene has emerged as a novel and fascinating two-dimensional (2D) material with exceptional features, such as anisotropic metallic behavior and supple mechanical and optical capabilities. The engineering of smart functionalized opto-electric 2D materials is essential to obtain biosensors or biodevices of desired performance. Borophene is one of the most emerging 2D materials, and owing to its excellent electroactive surface area, high electron transport, anisotropic behavior, controllable optical and electrochemical properties, ability to be deposited on thin films, and potential to create surface functionalities, it has recently become one of the sophisticated platforms. Despite the difficulty of production, borophene may be immobilized utilizing chemistries, be functionalized on a flexible substrate, and be controlled over electro-optical properties to create a highly sensitive biosensor system that could be used for point-of-care diagnostics. Its electrochemical properties can be tailored by using appropriate nanomaterials, redox mediators, conducting polymers, etc., which will be quite useful for the detection of biomolecules at even trace levels with a high sensitivity and less detection time. This will be quite helpful in developing biosensing devices with a very high sensitivity and with less response time. So, this review will be a crucial foundation as we have discussed the basic properties, synthesis, and potential applications of borophene in nanobiosensing, as well as therapeutic applications.


Assuntos
Nanoestruturas , Materiais Inteligentes , Medicina de Precisão , Anisotropia , Eletricidade , Transporte de Elétrons
3.
PLoS One ; 18(4): e0283954, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37014916

RESUMO

An in vitro model of the human blood-brain barrier was developed, based on a collagen hydrogel containing astrocytes, overlaid with a monolayer of endothelium, differentiated from human induced pluripotent stem cells (hiPSCs). The model was set up in transwell filters allowing sampling from apical and basal compartments. The endothelial monolayer had transendothelial electrical resistance (TEER) values >700Ω.cm2 and expressed tight-junction markers, including claudin-5. After differentiation of hiPSCs the endothelial-like cells expressed VE-cadherin (CDH5) and von-Willebrand factor (VWF) as determined by immunofluorescence. However, electron microscopy indicated that at set-up (day 8 of differentiation), the endothelial-like cells still retained some features of the stem cells, and appeared immature, in comparison with primary brain endothelium or brain endothelium in vivo. Monitoring showed that the TEER declined gradually over 10 days, and transport studies were best carried out in a time window 24-72hrs after establishment of the model. Transport studies indicated low permeability to paracellular tracers and functional activity of P-glycoprotein (ABCB1) and active transcytosis of polypeptides via the transferrin receptor (TFR1).


Assuntos
Barreira Hematoencefálica , Células-Tronco Pluripotentes Induzidas , Humanos , Células Cultivadas , Hidrogéis , Técnicas de Cocultura , Diferenciação Celular
4.
Sci Total Environ ; 875: 162598, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36882140

RESUMO

Technogenic soil (technosol) developed from coal fly ash (FA) landfilling has been considered a critical environmental problem worldwide. Drought-tolerant plants often naturally grow on FA technosol. However, the impact of these natural revegetations on the recovery of multiple ecosystem functions (multifunctionality) remains largely unexplored and poorly understood. Here we assessed the response of multifunctionality, including nutrient cycling (i.e., carbon, nitrogen, and phosphorus), carbon storage, glomalin-related soil protein (GRSP), plant productivity, microbial biomass carbon (MBC), microbial processes (soil enzyme activities), and soil chemical properties (pH and electrical conductivity; EC) to FA technosol ten years' natural revegetation with different multipurpose species in Indo-Gangetic plain, and identified the key factors regulating ecosystem multifunctionality during reclamation. We evaluated four dominant revegetated species: Prosopis juliflora, Saccharum spontaneum, Ipomoea carnea, and Cynodon dactylon. We found that natural revegetation initiated the recovery of ecosystem multifunctionality on technosol, with greater recovery under higher biomass-producing species (P. juliflora and S. spontaneum) than lower biomass-producing ones (I. carnea and C. dactylon). The individual functions (11 of the total 16 variables) at higher functionality (70 % threshold) also exhibited this pattern among revegetated stands. Multivariate analyses revealed that most of the variables (except EC) significantly correlated with multifunctionality, indicating the capability of multifunctionality to consider the tradeoff between individual functions. We further performed structural equation modeling (SEM) to detect the effect of vegetation, pH, nutrients, and microbial activity (MBC and microbial processes) on ecosystem multifunctionality. Our SEM model predicted 98 % of the variation in multifunctionality and confirmed that the indirect effect of vegetation mediated by microbial activity is more important for multifunctionality than their direct effect. Collectively, our results demonstrate that FA technosol revegetation with high biomass-producing multipurpose species promotes ecosystem multifunctionality and emphasizes the significance of microbial activity in the recovery and maintenance of ecosystem attributes.


Assuntos
Cinza de Carvão , Ecossistema , Cinza de Carvão/análise , Biomassa , Solo/química , Carbono/análise
5.
Biosensors (Basel) ; 13(2)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36831931

RESUMO

Nanobiosensors are devices that utilize a very small probe and any form of electrical, optical, or magnetic technology to detect and analyze a biochemical or biological process. With an increasing population today, nanobiosensors have become the broadly used electroanalytical tools for the timely detection of many infectious (dengue, hepatitis, tuberculosis, leukemia, etc.) and other fatal diseases, such as prostate cancer, breast cancer, etc., at their early stage. Compared to classical or traditional analytical methods, nanobiosensors have significant benefits, including low detection limit, high selectivity and sensitivity, shorter analysis duration, easier portability, biocompatibility, and ease of miniaturization for on-site monitoring. Very similar to biosensors, nanobiosensors can also be classified in numerous ways, either depending on biological molecules, such as enzymes, antibodies, and aptamer, or by working principles, such as optical and electrochemical. Various nanobiosensors, such as cyclic voltametric, amperometric, impedimetric, etc., have been discussed for the timely monitoring of the infectious and fatal diseases at their early stage. Nanobiosensors performance and efficiency can be enhanced by using a variety of engineered nanostructures, which include nanotubes, nanoparticles, nanopores, self-adhesive monolayers, nanowires, and nanocomposites. Here, this mini review recaps the application of two-dimensional (2D) materials, especially graphitic carbon nitride (g-C3N4), graphene oxide, black phosphorous, and MXenes, for the construction of the nanobiosensors and their application for the diagnosis of various infectious diseases at very early stage.


Assuntos
Técnicas Biossensoriais , Doenças Transmissíveis , Nanocompostos , Nanopartículas , Nanoestruturas , Nanotubos , Humanos , Nanoestruturas/química , Nanotecnologia/métodos , Técnicas Biossensoriais/métodos
6.
Artigo em Inglês | MEDLINE | ID: mdl-35895931

RESUMO

In the present study, we have isolated endosulfan tolerant bacterial strains from the rhizosphere of plants growing in a pesticide-contaminated area. The tolerance capacities of these strains were tested up to 50,000 µg ml-1 of endosulfan. It was found that out of nineteen, four strains (EAG-EC-12, EAG-EC-13, EAG-EC-14, and EAG-EC-15) were capable of surviving up to 50,000 µg ml-1 endosulfan concentration in the media; thus, these four strains were selected for the characterization. Among four, two strains were identified as Serratia liquefaciens, while the other two strains were Bacillus sp. and Brevibacterium halotolerans. The result shows that growth of strain Serratia liquefaciens 1 and Serratia liquefaciens 2 in treated medium was statistically similar to that of control (cfu 6.8 × 107) after 24 h, while strains Bacillus sp. and Brevibacterium halotolerans have shown growth significantly less than the control. The degradation potential of these strains was analyzed against 100 to 250 µg ml-1 of endosulfan in a Minimal Broth Medium (MBM), and it was recorded that only 9, 2, 7, and 19% of endosulfan (100 µg ml-1) remain after a 72 h incubation period of Bacillus sp., Serratia liquefaciens 1, Serratia liquefaciens 2, and Brevibacterium halotolerans, respectively. This endosulfan removal potential of studied strains was decreased with an increase in concentration of endosulfan.


Assuntos
Endossulfano , Poluentes do Solo , Bacillus , Bactérias/metabolismo , Biodegradação Ambiental , Endossulfano/análise , Endossulfano/metabolismo , Solo , Microbiologia do Solo
8.
Transplant Proc ; 54(2): 237-241, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35031118

RESUMO

BACKGROUND: Compensation after living donor nephrectomy is well known, and a compensation prediction score (CPS) was made in Japan previously. The aim of this study was to perform external validation of CPS in the United States. METHODS: We studied retrospectively 78 living donor nephrectomies in our institution. We defined a favorable compensation as a postdonation estimated glomerular filtration rate (eGFR) at 1 year of >60% of the predonation eGFR. We analyzed the living donors' clinical characteristics and outcomes and validated CPS score. RESULTS: The median (range) donor age was 43 (21-63) years, and median body mass index was 26.9 (18.3-35.9) kg/m2. Forty-four percent of donors were White. The donor predonation eGFR was 105 (61-134) mL/min/1.73 m2, and the postdonation eGFR at 1 year was 73.2 (0-115) mL/min/1.73 m2. Eighty-three percent of donors had a favorable compensation. The CPS was 9.6 (1.6-15.6) and showed strong diagnostic accuracy for predicting favorable compensation (area under the curve, 0.788; 95% confidence interval, 0.652-0.924; P = .001). The CPS showed a significant positive correlation with the postdonation eGFR at 1 year (R = 0.54; P < .001). CONCLUSIONS: In the United States, the CPS would be a valid tool with which to predict a favorable compensation of remnant kidney function.


Assuntos
Transplante de Rim , Doadores Vivos , Adulto , Taxa de Filtração Glomerular , Humanos , Rim/cirurgia , Pessoa de Meia-Idade , Nefrectomia , Estudos Retrospectivos , Estados Unidos
9.
J Environ Manage ; 298: 113423, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34526286

RESUMO

The Yellow River, with a developmental and historical significance to China, is now facing several emerging pressures, which are degrading the river status and creating challenges for high-quality development in the basin. Numerous studies on such emerging pressures, present scattered outcomes, and trigger uncertainties and deficient assumptions on the river's problems. This review integrated such scattered information and investigated the emerging pressures, their drivers and integrated impacts at the basin level. The study intended to prioritize those pressures needing expeditious consideration, and carried a discussion on the alternative pathways to the solution. To determine the critical emerging pressures, a literature review was conducted and experts' opinion was sought. The outcome further led to a comprehensive review, data collection, and analysis of three groups of emerging pressures. The review recognized 'Water Stress' in the lower reach, primarily caused by an abated flow, as the most distressing emerging pressure inflicting social, ecological, and economic consequences. Such decline in flow was mostly induced by a recent increase in 'Anthropogenic activities', such as intensive water withdrawal for irrigation (≥27 BCM), and construction of check dams in the Loess Plateau region (trapping~5 BCM water). The increasing 'Pollution' in the river, besides threatening public health and ecology, also contributed to the water stress by rendering certain stretches of the river biologically dead and unsuitable for any use. The 'Climate Change', with its key negative effect on precipitation in the middle sub-basin, overall contributed small (8-11 %) to the observed reduction in river flow. With increasing challenges for the adopted engineering solutions tackling the water stress, the study suggested the use of a demand management approach, employing adaptive policy measures, as an alternative or supplementary solution to the current approach. In addition, the study highlights that regular reviewing and reforming the key decisions based on evidence and updated information, and taking a participatory approach, may offer a sustainable pathway to the environment as well as socio-economic goals.


Assuntos
Rios , Movimentos da Água , Mudança Climática , Ecologia , Água
11.
Chemosphere ; 263: 128030, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33297051

RESUMO

Size-segregated airborne fine (PM2.1) and coarse (PM>2.1) particulates were measured in an urban environment over central Indo-Gangetic plain in between 2015 and 2018 to get insights into its nature, chemistry and sources. Mean (±1σ) concentration of PM2.1 was 98 (±76) µgm-3 with a seasonal high during winter (DJF, 162 ± 71 µgm-3) compared to pre-monsoon specific high in PM>2.1 (MAMJ, 177 ± 84 µgm-3) with an annual mean of 170 (±69) µgm-3. PM2.1 was secondary in nature with abundant secondary inorganic aerosols (20% of particulate mass) and water-soluble organic carbon (19%) against metal enriched (25%) PM>2.1, having robust signature of resuspensions from Earth's crust and road dust. Ammonium-based neutralization of particulate acidity was essentially in PM2.1 with an indication of predominant H2SO4 neutralization in bisulfate form compared to Ca2+ and Mg2+-based neutralization in PM>2.1. Molecular distribution of n-alkanes homologues (C17-C35) showed Cmax at C23 (PM2.1) and C18 (PM>2.1) with weak dominance of odd-numbered n-alkanes. Carbon preference index of n-alkanes was close to unity (PM2.1: 1.4 ± 0.3; PM>2.1: 1.3 ± 0.4). Fatty acids (C12-C26) were characterized with predominance of even carbon with Cmax at n-hexadecanoic acid (C16:0). Low to high molecular weight fatty acid ratio ranged from 2.0 (PM>2.1) to 5.6 (PM2.1) with vital signature of anthropogenic emissions. Levoglucosan was abundant in PM2.1 (758 ± 481 ngm-3) with a high ratio (11.6) against galactosan, emphasizing robust contribution from burning of hardwood and agricultural residues. Receptor model resolves secondary aerosols and biomass burning emissions (45%) as the most influential sources of PM2.1 whereas, crustal (29%) and secondary aerosols (29%) were found responsible for PM>2.1; with significant variations among the seasons.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Carbono/análise , Poeira/análise , Monitoramento Ambiental , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Emissões de Veículos/análise
12.
Chemosphere ; 257: 127145, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32497836

RESUMO

Sources of airborne particulates (PM10) were investigated in two contrasting sites over central Indo-Gangetic Plain (IGP), one representing a rural background (Mirzapur) and another as an urban pollution hotspot (Varanasi). Very high PM10 concentration was noted both in Varanasi (178 ± 105 µgm-3; N:435) and Mirzapur (131 ± 56 µgm-3; N:169) with 72% and 62% of monitoring days exceeded the national air quality standard, respectively. Particulate-bound elements contribute significant proportion of PM10 mass (15%-18%), with highest contribution from Ca (7%-10%) and Fe (2%-3%). Besides, presence of Zn (1%-3%), K (1%-2%) and Na (1%-2%) was also noted. Water-soluble ionic species contributed 15%-19% of particulate mass, primarily by the secondary inorganic aerosols (SIA). Among the SIA, sulphate (5%-7%) and nitrate (4%) were prominent, contributing 59%-62% of the total ionic load, especially in winter. Particulate-bound metallic species and ions were selectively used as signatory molecules and source apportionment of PM10 was done by multivariate factor analysis. UNMIX was able to extract particulate sources in both the locations and crustal resuspensions (dust/-soil) were identified as the dominant source contributing 57%-63% of PM10 mass. Secondary aerosols were the second important source (17%-23%), followed by emissions from biomass/-refuse burning (10-19%). Transport of airborne particulates from upper IGP by prevailing westerly were identified as the important contributor of particulates, especially during high particulate loading days. Health risks associated to particulate-bound toxic metal exposure were also assessed. Non-carcinogenic health risk was within the permissible limit while there is possibility of elevated risk for PM10-bound Cr and Cd, if adequate control measures are not in place.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Material Particulado/análise , Aerossóis/análise , Poluição do Ar/análise , Biomassa , Carvão Mineral/análise , Poeira/análise , Íons/análise , Metais/análise , Medição de Risco , Estações do Ano , Emissões de Veículos/análise
13.
Ecotoxicol Environ Saf ; 196: 110498, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247957

RESUMO

Two arsenic (As) hyper-tolerant bacterial strains NM01 Paracoccus versutus and NM04 Aeromonas caviae were isolated from As polluted site of West Bengal, India. The strains not only possess the potential to tolerate up to 20,000 mgl-1 As(V) and 10,000 mgl-1 As(III) but also possess plant growth promoting (PGP) traits like phosphate solubilization, siderophore production, IAA production. Greenhouse pot experiments were conducted to assess the effect of rhizospheric inoculation of both the strains individually and in consortia in As accumulation by Adiantum capillus-veneries. It was observed that the microbial inoculation significantly (p < 0.05) increased the synthesis of thiolic compounds and thus, enhanced As accumulation with translocation factor (TF) > 1. The strains regulated endogenous phytohormone up to 90% and 77.9% increase in auxin of consortia inoculated root and shoot, respectively. Interestingly, inoculation of the isolated strains augmented rhizospheric microbial diversity which was negatively affected by heavy metal. The results of high-throughput Illumina MiSeq sequencing technique to observe the composition of the bacterial community revealed 11,536 unique bacterial operational taxonomic units (OTUs) from As + S (non-inoculated), whereas 11,884 from Consortia As + S (inoculated) rhizospheric soil samples. Inoculated soil displayed higher bacterial diversity indices (ACE and Chao 1) with the dominant bacterial phyla Proteobacteria, Actinobacteria and Firmicutes. Our results highlight the innate PGP abilities of the strains and its potential to facilitate phytoextraction by enhancing As accumulation in the shoot.


Assuntos
Adiantum/metabolismo , Arsênio/metabolismo , Bactérias/metabolismo , Rizosfera , Poluentes do Solo/metabolismo , Adiantum/crescimento & desenvolvimento , Adiantum/microbiologia , Arsênio/análise , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Ácidos Indolacéticos/metabolismo , Microbiota/genética , Solo/química , Microbiologia do Solo , Poluentes do Solo/análise
14.
Environ Geochem Health ; 42(12): 4101-4111, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32060865

RESUMO

The presence of heavy metal in soil and water resources has serious impact on human health. The study was designed to examine the phytoremediation ability of plant species that are growing naturally on the Zn-contaminated site. For the study, six plant species and their rhizospheric soil as well as non-rhizospheric soil samples were collected from different parts of the industrial sites for chemical and biological characterization. Visual observations and highest importance value index (IVI) through biodiversity study revealed potential plants as effective ecological tools for the restoration of the contaminated site. Among the plants, almost all were the most efficient in accumulating Fe, Mn, Cu and Zn in its shoots and roots, while Cynodon dactylon, Chloris virgata and Desmostachya bipinnata were found to be stabilizing Cr, Pb and Cd (bioconcentration factor in root = 7.95, 6.28 and 1.98 as well as translocation factor = 0.48, 0.46 and 0.78), respectively. Thus, the results of this study showed that the naturally growing plant species have phytoremediation potential to remediate the electroplating wastewater-contaminated site. These plant species are successful phytoremediators with their efficient metal stabilizing and well-evolved tolerance to heavy metal toxicity.


Assuntos
Galvanoplastia , Metais Pesados/metabolismo , Plantas/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Biodegradação Ambiental , Biodiversidade , Metais Pesados/análise , Raízes de Plantas/classificação , Raízes de Plantas/metabolismo , Plantas/classificação , Rizosfera , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Poluentes Químicos da Água/análise
15.
Cureus ; 11(8): e5296, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31579636

RESUMO

Adenovirus causes significant morbidity and mortality in solid organ and hematological transplant recipients. Treatment of adenovirus infections includes supportive care, reduction of immune suppression, and in patients with severe disease, intravenous cidofovir. Brincidofovir (CMX001) is a lipid conjugate of cidofovir, with good oral bioavailability, no associated nephrotoxicity, and higher intracellular levels of the active drug compared to cidofovir. We describe a case of severe adenoviral pneumonia in an adult renal transplant recipient who was successfully treated with oral brincidofovir after developing renal insufficiency with intravenous cidofovir. Brincidofovir (CMX001) along with other supportive therapy, may offer an efficacious, safe, and well-tolerated treatment for severe adenoviral infections in solid organ transplant recipients.

16.
Ecotoxicol Environ Saf ; 182: 109462, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31351329

RESUMO

Wheat (W) and accumulators (A) were planted in plots (arsenic amended soil and without arsenic) designed with ecotoxicological concern for arsenic safe-grains. For the study sixteen plots of 2 × 2 × 0.5 m (l × b × h) size were prepared. Arsenic (As) in the form of sodium arsenate was applied at 50 mg/kg in plots. Out of these sixteen plots eight plots had arsenic amended soil and rest 8 without any arsenic (C). Accumulator's viz. Pteris vittata (PV), Phragmites australis (PA) and Vetiveria zizanioides (VZ) were planted along with wheat in combination (W + PV, W + PA and W + VZ) in twelve plots (6 AWAs plots and 6 AWC plots). In the rest 4 plots (2 WAs plots and 2 WC plots), only wheat was planted. The study was conducted for two cropping seasons, where accumulators were left in the plots between the cropping seasons except that before 2nd cropping accumulators were properly pruned and extra tillers were removed. The germination % of wheat in WAs in 1st and the 2nd cropping season was found to be 55 and 57%, while in AWAs and AWC plots it was between 86 and 92% (W + VZ, 56 and 73%). The physiological activity was found to be reduced in WAs plots compared to AWAs (except for vetiver combination) and AWC plots in both cropping seasons. The antioxidant activity was enhanced in WAs compared with AWAs. The arsenic concentration in grains of wheat was within the permissible limit set by WHO and GOI in AWAs plots while it exceeded the limit in W + VZ (in 1st cropping) and WAs in both cropings.


Assuntos
Antioxidantes/metabolismo , Arseniatos/análise , Poaceae/química , Pteris/química , Poluentes do Solo/análise , Triticum/química , Biodegradação Ambiental , Vetiveria/química , Vetiveria/crescimento & desenvolvimento , Poaceae/crescimento & desenvolvimento , Pteris/crescimento & desenvolvimento , Solo/química , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
17.
J Environ Manage ; 231: 1211-1221, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30602246

RESUMO

Tree growth rate can complicate our understandings of plant belowground responses to elevated CO2 (eCO2) in tropical ecosystems. We studied the effects of eCO2 on plant growth parameters, and rhizospheric soil properties including soil organic carbon (SOC), glomalin related soil protein (GRSP), microbial biomass C (Cmic), CO2 efflux (Cefflux), and microbial extracellular enzyme activities under two tropical tree saplings of fast-growing Tectona grandis (Teak) and slow-growing Butea monosperma (Butea). We exposed these saplings to eCO2 (∼550 ppm) and ambient CO2 (aCO2; ∼395 ppm) in the Indo-Gangetic plain region, and further (after 10 and 46 months) measured the changes in their rhizospheric soil properties. With respect to aCO2 treatment, eCO2 significantly increased plant height, stem and shoot weight, and total plant biomass of Teak. However, these plant traits did not considerably differed between eCO2 and aCO2 treatments of Butea. The eCO2 induced greater extent of increase in rhizospheric soil properties including SOC fractions (particulate OC, non-particulate OC and total OC), GRSP fractions (easily extractable- GRSP, difficulty extractable- GRSP and total- GRSP), Cmic, Cefflux and extracellular enzyme activities (phosphatase, dehydrogenase, ß-glucosidase and fluorescein diacetate) were observed under Teak compared with Butea. Compared with aCO2 treatment, eCO2 slightly reduced soil available N and P under the Teak, but no changes were apparent between eCO2 and aCO2 treatments of the Butea. The greater extent of responses from soil variables observed after longer period (46 months) of CO2 exposure. The multivariate analysis confirmed that eCO2 treatment with Teak is more responsive compared with other treatments of Teak and Butea. This contrasting rhizospheric soil feedback to eCO2 between two tropical trees, suggesting fast-growing species will be more responsive to future climate. Such species will have a competitive advantage over coexisting less responsive species (e.g. Butea) under future eCO2 climate.


Assuntos
Solo , Árvores , Dióxido de Carbono , Ecossistema , Clima Tropical
18.
Clin Transplant ; 32(12): e13428, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30338873

RESUMO

Simultaneous liver-kidney allocation protocols allocate dual organs based on a sustained eGFR of 30 mL/min or less. A 2017-UNOS update includes CKD3 as dual organ candidates but only when the listing eGFR is <30 mL/min while recommending a "safety net" for prioritized kidney listing post-LT. We retrospectively reviewed adult LTs examine whether the UNOS proposal captured the LT population at highest risk for developing post-LT ESRD. Among 290 LT recipients, 67 had pre-LT CKD3, 141 had AKI, of whom 47 required dialysis (<4 weeks). During follow-up, 25 (8.62%) developed ESRD, while 70 (24.1%) died. In adjusted Cox models, CKD3 had an independent association with post-LT ESRD (adjusted HR 4.8; P = 0.001), independent of AKI. Interestingly, CKD3 with listing GFR >30 mL/min was still significantly associated with post-LT ESRD. AKI was associated with reduced post-LT survival (adjusted HR 1.9; P = 0.02), albeit only in the first-year post-LT. Severe AKI-D was associated with post-LT ESRD and mortality. The safety net would have captured only 60% of all post-LT ESRD cases in our cohort. Pre-LT CKD3 was associated with increased risk of post-LT ESRD above the recommended cutoff for listing GFR. These findings, if generalizable in larger cohorts have important implications for dual organ allocation.


Assuntos
Doença Hepática Terminal/mortalidade , Rejeição de Enxerto/mortalidade , Sobrevivência de Enxerto , Falência Renal Crônica/complicações , Transplante de Fígado/mortalidade , Complicações Pós-Operatórias/mortalidade , Insuficiência Renal/complicações , Idoso , Estudos de Casos e Controles , Doença Hepática Terminal/cirurgia , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/patologia , Humanos , Testes de Função Renal , Transplante de Fígado/efeitos adversos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Prognóstico , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco
19.
Chemosphere ; 184: 1327-1333, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28679153

RESUMO

An experiment was designed using phytoremadiation technology to obtain grains of rice safe for consumption. Sixteen plots of size 2 × 2 m were prepared (8 plots were treated with 50 mg kg-1 of sodium arsenate and rest 8 without any treatment). The study was done for two plantations (1st and 2nd plantation). Rice was planted with three accumulators (Phragmites australis, Vetiveria zizanioides and Pteris vitatta) in treated and untreated plot. Arsenic in grains of Actr (R + Pt, R + Ph and R + Vt) for 1st plantation was 0.4, 0.2 and 0.2 mg kg-1 where as in the case of wActr (Ras) it was 3 mg kg-1. In 2nd plantation the concentration of arsenic in grain of Actr (R + Pt, R + Ph and R + Vt) was 0.1, 0.1 and 0.1 mg kg-1 where as in the case of wActr (Ras) it was 2 mg kg-1. Significant differences in growth and yield parameters of rice between Actr and wActr in 1st plantation, while for 2nd plantation the activity was reduced in combinations except R + Pt and no significant difference was observed between Actr, Acntr and wActr. The study concluded that combinations of accumulators with crops could be useful for the survival and safe grains in As-contaminated soils but with some amendments in long-term remediation.


Assuntos
Arsênio/análise , Recuperação e Remediação Ambiental , Oryza/química , Poluentes do Solo/análise , Arseniatos , Produtos Agrícolas , Grão Comestível/química , Poluição Ambiental , Oryza/crescimento & desenvolvimento , Oryza/metabolismo , Pteris
20.
J Environ Manage ; 192: 142-149, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28160641

RESUMO

Glomalin related soil protein (GRSP) is a hydrophobic glycoprotein that is significant for soil organic carbon (SOC) persistence and sequestration, owing to its large contribution to SOC pool and long turnover time. However, the contribution of GRSP to dissolve OC (DOC) leach from soil is not yet comprehensively explored, though it could have implication in understanding SOC dynamics. We, therefore, aim to measure the contribution of GRSP to DOC, in a range of land uses and climatic seasons in the dry tropical ecosystem. Our results demonstrated that a significant proportion of GRSP (water soluble GRSP; WS-GRSP) leached with DOC (7.9-21.9 mg kg-1), which accounts for 0.2-0.23% of soils total GRSP (T-GRSP). Forest exhibited significantly higher WS-GRSP and DOC leaching than fallow and agriculture. WS-GRSP and DOC accumulations were higher in the dry season (summer and winter) than in rainy. The extent of seasonal variations was higher in forest than in other two land uses, indicating the role of vegetation and biological activity in soil dissolve organic matter (DOM) dynamics. The regression analysis among WS-GRSP, T-GRSP, DOC and SOC prove that the accumulations and leaching of GRSP and other soil OM (SOM) depend on similar factors. The ratio of WS-GRSP-C to DOC was higher in agriculture soil than in forest and fallow, likely a consequence of altered soil chemistry, and organic matter quantity and quality due to soil management practices. Multivariate analysis reflects a strong linkage among GRSP and SOC storage and leaching, soil nutrients (nitrogen and phosphorus) and other important soil properties (pH and bulk density), suggesting that improving GRSP and other SOM status is an urgent need for the both SOC sequestration and soil health in dry tropical agro-ecosystems.


Assuntos
Carbono/análise , Proteínas Fúngicas/análise , Glicoproteínas/análise , Agricultura , Sequestro de Carbono , Clima , Ecossistema , Florestas , Nitrogênio/análise , Fósforo/análise , Solo/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA