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1.
Anal Chem ; 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326983

RESUMO

The total fissile content in seized nuclear materials is of immense importance and needs to be estimated with reasonable accuracy as a part of nuclear forensics for early decision-making in legal proceedings. High-resolution γ-ray spectrometry (HRGRS), because of its nondestructive nature, is a powerful tool for the assay of such samples to reach a quick "on-site" decision on the severity, intended use, and associated radiological threat. If the seized package contains fissile isotopes of more than one actinide in a multicompartmental heterogeneous mixture, analogous to the most likely scenario of a "smuggled mixed actinide basket", its "on-site" quantification can be extremely challenging. This makes up an increasing share of the absolute HRGRS in nuclear forensics and demands for fundamentally new approaches. In the present work, the challenges associated with varying attenuation experienced by γ-rays of different actinides at different subcontainments of the heterogeneous sample matrix have been addressed by an iterative efficiency transfer approach from "point" to "extended" source for individual actinides and demonstrated for the assay of four mock-up samples and a legacy packet, mimicking seized packages containing nuclear materials. An absolute isotopic inventory of the fissile and other radioisotopes has been obtained within <10% along with the assay of total U and Pu within <3% of the expected values with measurement uncertainty <10% for the majority. The present approach has a good potential for "on-site" nuclear forensics in nuclear smuggling scenarios and also can be adapted easily for a wide variety of other applications.

2.
Small ; : e2309428, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38529777

RESUMO

Bismuth sulfide (Bi2S3) exhibits a direct energy bandgap and an exceptional optical absorption capability over a broadband radiation, thus presents a novel class of 2D photodetector material. The field effect transistor (FET) photodetector device is fabricated from 2D Bi2S3. An anomalous variation in the transport characteristics of 2D Bi2S3 is observed with the variation in temperature. The electrical resistance reduces by 99.26% at 10 K compared to the response at 300 K. Defects due to the bismuth and sulfur vacancies play a critical role in the dramatic behavior, which is confirmed using photoluminescence, time-resolved photoluminescence, Hall measurements, and energy dispersive X-ray spectroscopy. The density functional theory calculations provide a significant insight into the thermodynamic properties of intrinsic defects in Bi2S3. Moreover, the effect of gate bias on responsivity additionally confirms its invariance at low temperature. The Bi2S3 based FET photodetector achieves ultrahigh responsivity in the order of ≈106 A W-1 and detectivity of ≈1014 Jones. Moreover, the external quantum efficiency of ≈107% is measured in a wide spectrum of optical illumination (532 to 1064 nm) with a noise-equivalent power of 3.5 × 10-18 W/√Hz at a bias of 0.2 V. The extraordinary performance of Bi2S3 photodetector outstands 2D photodetectors.

3.
Nano Lett ; 23(23): 10939-10945, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37976291

RESUMO

Two-dimensional (2D) materials hold great promise for future complementary metal-oxide semiconductor (CMOS) technology. However, the lack of effective methods to tune the Schottky barrier poses a challenge in constructing high-performance complementary circuits from the same material. Here, we reveal that the polarity of pristine MoTe2 field-effect transistors (FETs) with minimized air exposure is n-type, irrespective of the metal contact type. The fabricated n-FETs with palladium contact can reach electron currents up to 275 µA/µm at VDS = 2 V. For p-FETs, we introduce a novel nitric oxide doping strategy, allowing a controlled transition of MoTe2 FETs from n-type to unipolar p-type. By doping only in the contact region, we demonstrate hole currents up to 170 µA/µm at VDS= -2 V with preserved Ion/Ioff ratios of 105. Finally, we present a complementary inverter circuit comprising the high-performance n- and p-type FETs based on MoTe2, promoting the application of 2D materials in future electronic systems.

4.
Anal Chem ; 95(6): 3247-3254, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36722792

RESUMO

Several incidences of nuclear smuggling during the past few decades have raised the demand for the development of a strong "on-site" nuclear forensic infrastructure. High-resolution γ-ray spectrometry (HRGRS) plays an important role in nuclear forensics. However, the existing methodologies, developed primarily for nuclear fuel cycle applications, are relative and rely on the availability of a standard, limiting their use for the absolute assay of special nuclear materials in nonstandard geometry samples with an unknown matrix, which is vital to make a quick "on-site" decision on the severity, potential radiological threat, and intended use of an interdicted package. In this work, a methodology has been developed using HRGRS for quantifying fissile (235U, 239Pu) and other radioisotopes, which is applicable to sealed packages without requiring the knowledge of the sample geometry and the matrices. By combining experiments and Monte Carlo simulations, an iterative methodology has been proposed for "point" to "extended" source absolute efficiency transformation and demonstrated further for the absolute isotopic assay of uranium and plutonium standards, mock-up nuclear forensic samples, and an unknown nuclear material mixture with a nonstandard geometry, compound matrices, and a wide variation in the elemental and isotopic compositions with a view to imitate an "on-site" experience. The present methodology requires an assay time of only a few minutes to an hour and thus promises "on-site" nuclear forensic analysis of suspected flagged packages at borders and ports using high-resolution γ-ray spectrometry. Furthermore, the present methodology is versatile and can also be adopted for wider applications, beyond nuclear forensics.

5.
Int J Mol Sci ; 24(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37108725

RESUMO

Advances in the number and type of available biomaterials have improved medical devices such as catheters, stents, pacemakers, prosthetic joints, and orthopedic devices. The introduction of a foreign material into the body comes with a risk of microbial colonization and subsequent infection. Infections of surgically implanted devices often lead to device failure, which leads to increased patient morbidity and mortality. The overuse and improper use of antimicrobials has led to an alarming rise and spread of drug-resistant infections. To overcome the problem of drug-resistant infections, novel antimicrobial biomaterials are increasingly being researched and developed. Hydrogels are a class of 3D biomaterials consisting of a hydrated polymer network with tunable functionality. As hydrogels are customizable, many different antimicrobial agents, such as inorganic molecules, metals, and antibiotics have been incorporated or tethered to them. Due to the increased prevalence of antibiotic resistance, antimicrobial peptides (AMPs) are being increasingly explored as alternative agents. AMP-tethered hydrogels are being increasingly examined for antimicrobial properties and practical applications, such as wound-healing. Here, we provide a recent update, from the last 5 years of innovations and discoveries made in the development of photopolymerizable, self-assembling, and AMP-releasing hydrogels.


Assuntos
Anti-Infecciosos , Peptídeos Antimicrobianos , Humanos , Hidrogéis/farmacologia , Hidrogéis/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química
6.
Field Crops Res ; 241: 107578, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31534299

RESUMO

The requirement of rice (Oryza sativa L.) for fertilizer can depend on crop and soil management practices, which can vary among fields within a rice-growing area. A web-based decision support tool named Rice Crop Manager (RCM) was developed previously to calculate field-specific rates of fertilizer N, P, and K for rice in Odisha State in eastern India. We compared field-specific nutrient management calculated by RCM with farmers' fertilizer practice (FFP) and a blanket fertilizer recommendation (BFR), which used a uniform 80 kg N ha-1, 17 kg P ha-1, and 33 kg K ha-1. A total of 209 field trials were conducted in two seasons (kharif and rabi) for two years across ten districts in six agro-climatic zones. Grain yield was consistently higher with fertilization recommended by RCM than with FFP. Higher yield with RCM was attributed to a combination of applying more of the total fertilizer N at the critical growth stage of panicle initiation, applying more fertilizer N in kharif, and applying zinc. The RCM recommendation frequently increased yield compared to BFR as a result of improved N management, which included the adjustment of N rate for a target yield set slightly higher than historical yield reported by a farmer. Fertilization based on RCM rather than BFR reduced the risk of financial loss. The effectiveness of an RCM recommendation relative to BFR and FFP was consistent across rice varieties with different growth duration, irrigated and rainfed rice, and three categories of soil clay content. The RCM recommendation failed to increase yield relative to BFR in one of the six agro-climatic zones, where a higher rate of fertilizer P and/or K was apparently required. The nutrient management calculations used by RCM can be improved as new information and research findings become available. Experiences with RCM in Odisha can help guide the development of comparable nutrient management decision tools in other rice-growing areas.

7.
AAPS PharmSciTech ; 20(2): 51, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30617845

RESUMO

This work reports the synthesis of multi-walled carbon nanotubes (CNTs) from xylene/ferrocene using catalytic chemical vapor deposition technique. Following characterization using transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), and Raman spectroscopy, CNT surface was dual-functionalized using ethylenediamine and phenylboronic acid groups. Average diameter of CNTs was calculated to be 16.5 nm. EDX spectra confirmed the existence of carbonaceous deposits on the tube's surface. Scattered electron diffraction and X-ray peak broadening calculations showed consistent inter-planer distance of the grown CNTs. Chemical functionalization, confirmed from FT-IR and Raman spectra, showed an enhanced dispersibility of CNTs in water. We describe the changes in the first- and second-order regions of the Raman spectra following the encapsulation of an anti-cancer drug, paclitaxel (PLX), into the free volume of functionalized CNTs. High PLX loading, achieved through its non-covalent π-π stacking within the CNT interior, is confirmed through the blue-shifted, softened G band in the Raman spectrum. While not addressed here, we will exploit this dual functionalization tactic to elaborate the relative role of attached moieties in the affinity interaction of CNTs with extra-cellular sialic acid, a biological target showing metastatic stage-dependent over-expression in colon cancer cells.


Assuntos
Antineoplásicos Fitogênicos/química , Composição de Medicamentos/métodos , Nanotubos de Carbono/química , Paclitaxel/química , Microscopia Eletrônica de Transmissão/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Análise Espectral Raman/métodos , Difração de Raios X/métodos
8.
Environ Monit Assess ; 191(9): 550, 2019 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-31396767

RESUMO

A field experiment was conducted at Indian Council of Agricultural Research-National Rice Research Institute, Cuttack, Odisha, India in the dry seasons of 2015 and 2016 to assess the water vapor flux (FH2O) and its relationship with other climatic variables. The FH2O and climatic variables were measured by an eddy covariance system and a micrometeorological observatory. Daily mean FH2O during the dry seasons of 2015 and 2016 were 0.009-0.092 g m-2 s-1 and 0.014-0.101 g m-2 s-1, respectively. Seasonal average FH2O was 14.6% higher in 2016 than that in 2015. Diurnal variation for FH2O showed a bell-shaped curve with its peak at 13:30-14:00 Indian Standard Time (IST) in both the years. Carbon dioxide flux was found higher with rise in FH2O. This relationship was stronger at higher vapor pressure deficit (VPD) (20 ≤ VPD ≤ 40 and VPD > 40 hPa). The FH2O showed significant positive correlation with latent heat flux, net radiation flux, photosynthatically active radiation, air, water and soil temperatures, shortwave down and upwell radiations, maximum and minimum temperatures, evaporation, and relative humidity in both the years. Principal component analysis showed that FH2O was very close to latent heat flux in both the years (Pearson correlation coefficient close to 1). The two-dimensional observation map of the principal component F1 and F2 showed the observations taken during the vegetative stage and panicle initiation stage, and flowering stage and maturity stage were closer to each other. It can be concluded that the most important climatic variables controlling the FH2O were latent heat of vaporization, net radiation, air temperature, soil temperatures, and water temperature.


Assuntos
Ciclo do Carbono/fisiologia , Monitoramento Ambiental/métodos , Oryza/química , Vapor/análise , Agricultura , Dióxido de Carbono/análise , Ecossistema , Índia , Análise de Componente Principal , Estações do Ano , Solo/química , Temperatura , Água/química
9.
Environ Monit Assess ; 191(2): 98, 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30675638

RESUMO

Land use and land cover (LULC) change have considerable influence on ecosystem services. Assessing change in ecosystem services due to LULC change at different spatial and temporal scales will help to identify suitable management practices for sustaining ecosystem productivity and maintaining the ecological balance. The objective of this study was to investigate variations in ecosystem services in response to LULC change over 27 years in four agro-climatic zones (ACZ) of eastern India using satellite imagery for the year 1989, 1996, 2005, 2011 (Landsat TM) and 2016 (Landsat 8 OLI). The satellite images were classified into six LULC classes, agriculture land, forest, waterbody, wasteland, built-up, and mining area. During the study period (1989 to 2016), forest cover reduced by 5.2%, 13.7%, and 3.6% in Sambalpur, Keonjhar, and Kandhamal districts of Odisha, respectively. In Balasore, agricultural land reduced by 17.2% due to its conversion to built-up land. The value of ecosystem services per unit area followed the order of waterbodies > agricultural land > forests. A different set of indicators, e.g., by explicitly including diversity, could change the rank between these land uses, so the temporal trends within a land use are more important than the absolute values. Total ecosystem services increased by US$ 1296.4 × 105 (50.74%), US$ 1100.7 × 105 (98.52%), US$ 1867 × 105 (61.64%), and US$ 1242.6 × 105 (46.13%) for Sambalpur, Balasore, Kandhamal, and Keonjhar, respectively.


Assuntos
Mudança Climática , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental/métodos , Agricultura/métodos , Ecossistema , Florestas , Índia , Mineração , Imagens de Satélites/métodos
10.
Int J Biometeorol ; 62(8): 1375-1387, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29644433

RESUMO

It is reported that high temperatures (HT) would cause a marked decrease in world rice production. In tropical regions, high temperatures are a constraint to rice production and the most damaging effect is on spikelet sterility. Boron (B) plays a very important role in the cell wall formation, sugar translocation, and reproduction of the rice crop and could play an important role in alleviating high temperature stress. A pot culture experiment was conducted to study the effect of B application on high temperature tolerance of rice cultivars in B-deficient soil. The treatments comprised of four boron application treatments viz. control (B0), soil application of 1 kg B ha-1 (B1), soil application of 2 kg B ha-1 (B2), and foliar spray of 0.2% B (Bfs); three rice cultivars viz. Annapurna (HT stress tolerant), Naveen, and Shatabdi (both HT stress susceptible); and three temperature regimes viz. ambient (AT), HT at vegetative stage (HTV), and HT at reproductive stage (HTR). The results revealed that high temperature stress during vegetative or flowering stage reduced grain yield of rice cultivars mainly because of low pollen viability and spikelet fertility. The effects of high temperature on the spikelet fertility and grain filling varied among cultivars and the growth stages of plant when exposed to the high temperature stress. Under high temperature stress, the tolerant cultivar displays higher cell membrane stability, less accumulation of osmolytes, more antioxidant enzyme activities, and higher pollen viability and spikelet fertility than the susceptible cultivars. In the present work, soil application of boron was effective in reducing the negative effects of high temperature both at vegetative and reproductive stages. Application of B results into higher grain yield under both ambient and high temperature condition over control for all the three cultivars; however, more increase was observed for the susceptible cultivar over the tolerant one. The results suggest that the exogenous application of boron had a substantial effect on cell membrane stability, sugar mobilization, pollen viability, and spikelet fertility, hence the yield. The cultivars due to their variation in the tolerance level for high temperature stress behaved differently, and at high temperature stress, more response of the application of boron was seen in susceptible cultivars.


Assuntos
Boro , Temperatura Alta , Oryza/crescimento & desenvolvimento , Reprodução , Temperatura
11.
Environ Monit Assess ; 190(7): 423, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-29938374

RESUMO

Lowland tropical rice-rice system has a unique micrometrological characteristic that affects both energy component and net ecosystem energy. Periodic and seasonal variations of methane (CH4), carbon dioxide (CO2), and energy exchange from irrigated lowland rice-rice ecosystem were studied using open-path eddy covariance (EC) system during the dry (DS) and wet (WS) seasons in 2015. Concurrently, the manual chamber method was employed in nitrous oxide (N2O) measurement efflux. Cumulative net ecosystem carbon exchange (NEE) was observed highest (- 232.55 g C m-2) during the WS and lowest (- 14.81 g C m-2) during wet fallow (WF). Similarly, the cumulative net ecosystem methane exchange (NEME) was found highest (13,456.5 mg CH4 m-2) during the WS and lowest (2014.3 mg CH4 m-2) during the WF. Surface energy fluxes, i.e., sensible (Hs) and latent heat (LE) fluxes, showed a similar trend. With the advancement of time, the ratio of ecosystem respiration (Re) and gross primary production (GPP) increased. The cumulative global warming potential (GWP) for the two cropping seasons including two fallows was 13,224.1 kg CO2 equivalent ha-1. The GWP and NEME showed a similar trend as soil enzymes and labile carbon pools in both seasons (except GWP at the harvesting stage in the wet season). The mean NEE exhibited a more negative value with decrease in labile pools from panicle initiation to harvesting stage in the WS. Soil labile C and soil enzymes can be used as an indicator of NEE, NEME, and GWP in lowland rice ecology. Graphical abstract Schematic presentation of GHG emission and energy exchange in lowland rice.


Assuntos
Agricultura , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental , Gases de Efeito Estufa/análise , Carbono , Dióxido de Carbono/análise , Ecossistema , Aquecimento Global , Metano/análise , Óxido Nitroso/análise , Oryza , Estações do Ano , Solo
12.
Nanotechnology ; 28(39): 395101, 2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28696341

RESUMO

Multiwalled carbon nanotubes (CNTs) are uniformly distributed with piezoelectric microspheres. This leads to a large strain gradient due to an induced capacitive response, providing a 250% enhancement in electromechanical response compared with pristine CNTs. The fabricated large-area flexible thin film exhibits excellent pressure sensitivity, which can even detect an arterial pulse with a much faster response time (∼79 ms) in a bendable configuration. In addition, the film shows a rapid relaxation time (∼0.4 s), high stability and excellent durability with a rapid loading-unloading cycle. The dominant contribution of piezoelectric microspheres in a CNT matrix as opposed to nanoparticles showed a much higher sensitivity due to the large change in capacitance. Therefore, hybrid microstructures have various potential applications in wearable smart electronics, including detection of human motion and wrist pulses.

13.
AAPS PharmSciTech ; 17(4): 878-90, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26392403

RESUMO

Generally, pellets obtained from extrusion/spheronization, containing microcrystalline cellulose (MCC), do not disintegrate. An attempt has been made to develop melt-in-mouth pellets of taste-masked atomoxetine hydrochloride, using extrusion-spheronization, for pediatric patients. Melt-in-mouth pellets were prepared using extrusion-spheronization method and optimized using 3(3) FFD. MCC (X1, %), mannitol (X2, %) and Indion 414: Pharmaburst 500 ratio (X3, ratio) were the factors (independent variables) studied, whereas responses studied (dependent variables) were friability (Y1, %), yield (Y2, %) shape (Y3, roundness) in vitro disintegration time (Y4, seconds). The optimized formulation obtained from FFD was characterized for friability, shape and morphology, in vitro disintegration time, porosity, moisture uptake, in vitro release study and in vivo taste and disintegration time in healthy human volunteers. Randomized, two-treatment, two-sequence, two-period, single dose, crossover sensory evaluation study of taste-masked melt-in-mouth pellet was carried out in 10 healthy human subjects. A statistically significant polynomial mathematical relationship was generated between the factors and responses to obtain an optimized formulation. The optimized formulation was characterized (in vitro and in vivo) and exhibited a rapid drug release in vitro attributed to fast disintegration of pellets and high solubility of drug in 0.1 N HCl and buffer (pH 6.8). In vivo, 40% of volunteers ranked taste-masked optimized formulation as slightly bitter while 60% ranked it as no taste. The optimized pellets were conveniently administered in volunteers and exhibited rapid in-vivo disintegration in the oral cavity. Melt-in-mouth pellets can be a used as a platform technology for administering drugs to paediatric patients accurately and conveniently resulting in patient compliance.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Implantes de Medicamento/administração & dosagem , Implantes de Medicamento/química , Boca/metabolismo , Adulto , Celulose/química , Química Farmacêutica/métodos , Estudos Cross-Over , Excipientes/química , Feminino , Humanos , Masculino , Manitol/química , Pediatria , Ácidos Polimetacrílicos/química , Solubilidade , Paladar/efeitos dos fármacos
14.
PLoS One ; 19(4): e0301971, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38648227

RESUMO

This work, in a pioneering approach, attempts to build a biometric system that works purely based on the fluid mechanics governing exhaled breath. We test the hypothesis that the structure of turbulence in exhaled human breath can be exploited to build biometric algorithms. This work relies on the idea that the extrathoracic airway is unique for every individual, making the exhaled breath a biomarker. Methods including classical multi-dimensional hypothesis testing approach and machine learning models are employed in building user authentication algorithms, namely user confirmation and user identification. A user confirmation algorithm tries to verify whether a user is the person they claim to be. A user identification algorithm tries to identify a user's identity with no prior information available. A dataset of exhaled breath time series samples from 94 human subjects was used to evaluate the performance of these algorithms. The user confirmation algorithms performed exceedingly well for the given dataset with over 97% true confirmation rate. The machine learning based algorithm achieved a good true confirmation rate, reiterating our understanding of why machine learning based algorithms typically outperform classical hypothesis test based algorithms. The user identification algorithm performs reasonably well with the provided dataset with over 50% of the users identified as being within two possible suspects. We show surprisingly unique turbulent signatures in the exhaled breath that have not been discovered before. In addition to discussions on a novel biometric system, we make arguments to utilise this idea as a tool to gain insights into the morphometric variation of extrathoracic airway across individuals. Such tools are expected to have future potential in the area of personalised medicines.


Assuntos
Algoritmos , Testes Respiratórios , Expiração , Aprendizado de Máquina , Humanos , Expiração/fisiologia , Testes Respiratórios/métodos , Identificação Biométrica/métodos
15.
Integr Biol (Camb) ; 152023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-37635325

RESUMO

Neurodegenerative disorders (NDDs) are known to exhibit genetic overlap and shared pathophysiology. This study aims to find the shared genetic architecture of Alzheimer's disease (AD) and Parkinson's disease (PD), two major age-related progressive neurodegenerative disorders. The gene expression profiles of GSE67333 (containing samples from AD patients) and GSE114517 (containing samples from PD patients) were retrieved from the Gene Expression Omnibus (GEO) functional genomics database managed by the National Center for Biotechnology Information. The web application GREIN (GEO RNA-seq Experiments Interactive Navigator) was used to identify differentially expressed genes (DEGs). A total of 617 DEGs (239 upregulated and 379 downregulated) were identified from the GSE67333 dataset. Likewise, 723 DEGs (378 upregulated and 344 downregulated) were identified from the GSE114517 dataset. The protein-protein interaction networks of the DEGs were constructed, and the top 50 hub genes were identified from the network of the respective dataset. Of the four common hub genes between two datasets, C-X-C chemokine receptor type 4 (CXCR4) was selected due to its gene expression signature profile and the same direction of differential expression between the two datasets. Mavorixafor was chosen as the reference drug due to its known inhibitory activity against CXCR4 and its ability to cross the blood-brain barrier. Molecular docking and molecular dynamics simulation of 51 molecules having structural similarity with Mavorixafor was performed to find two novel molecules, ZINC49067615 and ZINC103242147. This preliminary study might help predict molecular targets and diagnostic markers for treating Alzheimer's and Parkinson's diseases. Insight Box Our research substantiates the therapeutic relevance of CXCR4 inhibitors for the treatment of Alzheimer's and Parkinson's diseases. We would like to disclose the following insights about this study. We found common signatures between Alzheimer's and Parkinson's diseases at transcriptional levels by analyzing mRNA sequencing data. These signatures were used to identify putative therapeutic agents for these diseases through computational analysis. Thus, we proposed two novel compounds, ZINC49067615 and ZINC103242147, that were stable, showed a strong affinity with CXCR4, and exhibited good pharmacokinetic properties. The interaction of these compounds with major residues of CXCR4 has also been described.


Assuntos
Doença de Alzheimer , Doença de Parkinson , Receptores CXCR4 , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Aminoquinolinas , Simulação de Acoplamento Molecular , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Receptores CXCR4/antagonistas & inibidores
16.
Ageing Res Rev ; 86: 101855, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36681250

RESUMO

Necroptosis, a regulated form of cell death, is involved in the genesis and development of various life-threatening diseases, including cancer, neurological disorders, cardiac myopathy, and diabetes. Necroptosis initiates with the formation and activation of a necrosome complex, which consists of RIPK1, RIPK2, RIPK3, and MLKL. Emerging studies has demonstrated the regulation of the necroptosis cell death pathway through the implication of numerous post-translational modifications, namely ubiquitination, acetylation, methylation, SUMOylation, hydroxylation, and others. In addition, the negative regulation of the necroptosis pathway has been shown to interfere with brain homeostasis through the regulation of axonal degeneration, mitochondrial dynamics, lysosomal defects, and inflammatory response. Necroptosis is controlled by the activity and expression of signaling molecules, namely VEGF/VEGFR, PI3K/Akt/GSK-3ß, c-Jun N-terminal kinases (JNK), ERK/MAPK, and Wnt/ß-catenin. Herein, we briefly discussed the implication and potential of necrosome activation in the pathogenesis and progression of neurological manifestations, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, traumatic brain injury, and others. Further, we present a detailed picture of natural compounds, micro-RNAs, and chemical compounds as therapeutic agents for treating neurological manifestations.


Assuntos
Doenças do Sistema Nervoso , Proteínas Quinases , Humanos , Proteínas Quinases/metabolismo , Necroptose/fisiologia , Glicogênio Sintase Quinase 3 beta , Fosfatidilinositol 3-Quinases , Apoptose
17.
Saudi J Kidney Dis Transpl ; 34(1): 21-33, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38092713

RESUMO

The glomerular filtration rate (GFR) is important for assessing renal function and must be calculated reliably and reproducibly. This study aimed to compare the reliability and accuracy of GFR estimated with 99m-technetium diethylene-triamine-pentaacetate (99mTc-DTPA) versus that calculated from the effective renal plasma flow (ERPF) (GFR is 20% of ERPF) determined by the 99m-technetium ethylene dicysteine (99mTc-EC) technique. Forty-five patients suffering from cancer requiring platinum compound-based chemotherapy or from chronic renal failure were recruited. The patients were divided into two cohorts: (1) those with normal serum creatinine (SCr) levels (≤2 mg/dL) and (2) deranged SCr levels (>2 mg/dL). For all patients, the relative renal function was estimated by the 99mTc-DTPA and 99mTc-EC methods, 2-4 days apart. A 24-h urine sample for estimating 24-h creatinine clearance (CrCl) was obtained. GFR was also calculated using the Modification of Diet in Renal Disease (MDRD) formula. The GFR estimated via 24-h urine CrCl, 99mTc-DTPA, and ERPF obtained with 99mTc-EC were examined by quantile comparison plots, and all showed evidence of following a non-Gaussian distribution. For SCr values ≤2 mg/dL, the GFR estimated by the MDRD formula consistently shows significantly higher values than the GFR estimated with 99mTc-DTPA or 99mTc-EC. We found a high degree of correlation between the 99mTc-DTPA and 99mTc-EC radionuclide methods of estimating GFR. However, in patients with renal dysfunction, GFR estimated through Gates' method using a gamma camera overestimated the GFR; in these patients, calculating the GFR from the ERPF obtained with 99mTc-EC is more accurate.


Assuntos
Fluxo Plasmático Renal Efetivo , Tecnécio , Humanos , Creatinina , Taxa de Filtração Glomerular , Ácido Pentético , Reprodutibilidade dos Testes , Pentetato de Tecnécio Tc 99m
18.
Heliyon ; 9(7): e17835, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37519636

RESUMO

The role of biochar in improving the soil properties of problem soils is well known, but its long term impact on lowland rice soil is not well recognized. The soil quality indicators of biochar applied lowland rice soil are not widely reported. We developed soil quality index (SQI) of a biochar applied lowland rice soil based on 17 soil properties (indicators). Field experimentation consisted of six treatments such as 0.5, 1, 2, 4, 8 and 10 t ha-1 of rice husk derived biochar (RHB) along with control. An overall SQI was calculated encompassing the indicators using multivariate statistics (principal component analysis) and non-linear scoring functions after generation of minimum data set (MDS). Sequential application of RHB improved the SQI by 4.85% and 16.02% with application of 0.5 t ha-1 and 10 t ha-1 RHB, respectively, over the recommended dose of fertilizer (control). PCA-screening revealed that total organic carbon (Ctot), zinc (Zn), pH and bulk density (BD) were the main soil quality indicators for MDS with 27.79%, 26.61%, 23.67% and 14.47% contributions, respectively. Apart from Ctot, Zn is one of the major contributors to SQI and RHB application can potentially be an effective agronomic practice to improve Zn status in lowland rice soil. The overall SQI was significantly influenced by RHB application even at 0.5 t ha-1. The present study highlights that application of RHB improves the soil quality even in fertile, well managed, lowland rice soil.

19.
Front Plant Sci ; 14: 1130545, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37143878

RESUMO

Introduction: Conventional rice production techniques are less economical and more vulnerable to sustainable utilization of farm resources as well as significantly contributed GHGs to atmosphere. Methods: In order to assess the best rice production system for coastal areas, six rice production techniques were evaluated, including SRI-AWD (system of rice intensification with alternate wetting and drying (AWD)), DSR-CF (direct seeded rice with continuous flooding (CF)), DSR-AWD (direct seeded rice with AWD), TPR-CF (transplanted rice with CF), TPR-AWD (transplanted rice with AWD), and FPR-CF (farmer practice with CF). The performance of these technologies was assessed using indicators such as rice productivity, energy balance, GWP (global warming potential), soil health indicators, and profitability. Finally, using these indicators, a climate smartness index (CSI) was calculated. Results and discussion: Rice grown with SRI-AWD method had 54.8 % higher CSI over FPR-CF, and also give 24.5 to 28.3% higher CSI for DSR and TPR as well. There evaluations based on the climate smartness index can provide cleaner and more sustainable rice production and can be used as guiding principle for policy makers.

20.
AAPS PharmSciTech ; 13(4): 1091-102, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22936406

RESUMO

In the present study, grafting technology has been used to develop novel grafted hydrogel beads as controlled drug delivery carriers. The chemical crosslinking and grafting of polyacrylamide onto sodium alginate has been found to be efficient method for the development of new polymeric carrier. The successful crosslinking has been confirmed by Fourier transformed infrared spectroscopy, thermogravimetric analysis, and elemental analysis. The polymeric network of sodium alginate-co-polyacrylamide (NaAlg-g-PAM) has been interlinked by covalent and hydrogen bonds which also strength the gel network. Simple ionotropic gelation method has been used for the preparation of NaAlg-g-PAM hydrogel beads. Its swelling and gelation were dependent on monomer and crosslinker concentrations. Entrapment of the drug moiety (famotidine; an antiulcer drug) within the grafted beads has been confirmed by X-ray powder diffraction and differential scanning calorimetry. More than 75% of drug loading in beads occurred with the increase of monomer and crosslinker concentration. In vitro drug release was found to be sustained up to the 12 h with 80% drug release.


Assuntos
Resinas Acrílicas/química , Alginatos/química , Portadores de Fármacos/química , Famotidina/administração & dosagem , Famotidina/química , Mucosa Gástrica/metabolismo , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Antiulcerosos/administração & dosagem , Antiulcerosos/química , Varredura Diferencial de Calorimetria/métodos , Preparações de Ação Retardada/química , Sistemas de Liberação de Medicamentos/métodos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Modelos Biológicos , Espectroscopia de Infravermelho com Transformada de Fourier , Estômago/efeitos dos fármacos , Difração de Raios X/métodos
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