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1.
RSC Adv ; 13(50): 35088-35126, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38046631

RESUMO

Over the past decade, carbon dots (CDs) have emerged as some of the extremely popular carbon nanostructures for diverse applications. The advantages of sustainable CDs, characterized by their exceptional photoluminescence (PL), high water solubility/dispersibility, non-toxicity, and biocompatibility, substantiate their potential for a wide range of applications in sensing and biology. Moreover, nature offers plant- and animal-derived precursors for the sustainable synthesis of CDs and their doped variants. These sources are not only readily accessible, inexpensive, and renewable but are also environmentally benign green biomass. This review article presents in detail the production of sustainable CDs from various animal and human biomass through bottom-up synthetic methods, including hydrothermal, microwave, microwave-hydrothermal, and pyrolysis methods. The resulting CDs exhibit a uniform size distribution, possibility of heteroatom doping, surface passivation, and remarkable excitation wavelength-dependent/independent emission and up-conversion PL characteristics. Consequently, these CDs have been successfully utilized in multiple applications, such as bioimaging and the detection of various analytes, including heavy metal ions. Finally, a comprehensive assessment is presented, highlighting the prospects and challenges associated with animal/human biomass-derived CDs for multifaceted applications.

2.
Sci Rep ; 13(1): 20675, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38001163

RESUMO

In the context of emerging electric devices, the demand for advanced energy storage materials has intensified. These materials must encompass both surface and diffusion-driven charge storage mechanisms. While diffusion-driven reactions offer high capacitance by utilizing the bulk of the material, their effectiveness diminishes at higher discharge rates. Conversely, surface-controlled reactions provide rapid charge/discharge rates and high power density. To strike a balance between these attributes, we devised a tri-composite material, TiO2/Carbon/MoS2 (T10/MoS2). This innovative design features a highly porous carbon core for efficient diffusion and redox-active MoS2 nanosheets on the surface. Leveraging these characteristics, the T10/MoS2 composite exhibited impressive specific capacitance (436 F/g at 5 mV/s), with a significant contribution from the diffusion-controlled process (82%). Furthermore, our symmetrical device achieved a notable energy density of ~ 50 Wh/kg at a power density of 1.3 kW/kg. This concept holds promise for extending the approach to other Metal-Organic Framework (MOF) structures, enabling enhanced diffusion-controlled processes in energy storage applications.

3.
Cureus ; 15(8): e43363, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37701004

RESUMO

Sarcoidosis is an immune-mediated disease that can involve multiple systems. Sarcoidosis of the nervous system or neurosarcoidosis may present as cranial mononeuropathy, hypothalamic involvement, aseptic meningitis, granulomatous inflammation in the brain parenchyma or spinal cord, peripheral neuropathy, and, in rare cases, as myopathy and benign intracranial hypertension. The most common cranial nerve involvement is the facial nerve, which can present as unilateral or bilateral facial nerve palsy, often with recurrent episodes. Involvement of other cranial nerves such as the second and eighth cranial nerves has also been reported. Granulomatous inflammation in the spinal cord presents as myelopathy or radiculopathy. Peripheral neuropathy can manifest as mononeuropathy, mononeuritis multiplex, or generalized sensory-motor neuropathy. Carpal tunnel syndrome is more common in patients with sarcoidosis compared to the general population. Here, we describe the case of a 40-year-old female who presented with heaviness of the head and blurred vision, with a prior history of left-sided Bell's palsy. Bilateral papilledema was observed during the fundus examination. MRI of the brain revealed signs suggestive of benign intracranial hypertension. The cerebrospinal fluid (CSF) opening pressure was measured at 40 cmH2O. Biopsy of bilateral hilar lymphadenopathy indicated granulomatous inflammation consistent with sarcoidosis. The patient was started on steroids and acetazolamide, and she had a dramatic improvement in symptoms.

5.
Adv Colloid Interface Sci ; 318: 102967, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37523999

RESUMO

Establishing green and reliable energy resources is very important to counteract the carbon footprints and negative impact of non-renewable energy resources. Metal-organic frameworks (MOFs) are a class of porous material finding numerous applications due to their exceptional qualities, such as high surface area, low density, superior structural flexibility, and stability. Recently, increased attention has been paid to surface mounted MOFs (SURMOFs), which is nothing but thin film of MOF, as a new category in nanotechnology having unique properties compared to bulk MOFs. With the advancement of material growth and synthesis technologies, the fine tunability of film thickness, consistency, size, and geometry with a wide range of MOF complexes is possible. In this review, we recapitulate various synthesis approaches of SURMOFs including epitaxial synthesis approach, direct solvothermal method, Langmuir-Blodgett LBL deposition, Inkjet printing technique and others and then correlated the synthesis-structure-property relationship in terms of energy storage and conversion applications. Further the critical assessment and current problems of SURMOFs have been briefly discussed to explore the future opportunities in SURMOFs for energy storage and conversion applications.

6.
Infect Dis (Lond) ; 55(11): 755-766, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37480325

RESUMO

BACKGROUND: Identifying early predictors of severe Covid-19 associated mucormycosis (CAM) can help improve management and treatment outcomes. OBJECTIVES: Primary: To identify clinical and radiological predictors of disease severity in CAM. Secondary: To describe patterns of central nervous system (CNS) involvement in CAM. METHODS: A total of 71 patients with CAM were included in the study. Based on the anatomical extent of involvement on MRI, patients were divided into three groups: Sinus (paranasal sinuses), Orbit (orbital spread), and CNS (CNS spread). Clinical parameters and radiological patterns of involvement of sinuses and extra sinus spaces were studied between the three groups. Patterns of CNS involvement were also described. RESULTS: A shorter time lag between COVID-19 infection and CAM, as well as high HbA1C levels, were found to be associated with severe disease. Involvement of the sphenoid, ethmoid and frontal sinuses, T1 hyperintense signal in the sphenoid, as well as bony involvement of the sphenoid sinus, were significantly associated with severe disease. Extra-sinus spread into pre/retroantral space, pterygopalatine fossa, and masticator spaces were also significantly associated with a severe disease course. The most common pattern of CNS spread was cavernous sinus involvement, followed by pachymeningeal spread and cranial nerve involvement. CONCLUSION: Early identification of the above-described predictors in patients presenting with CAM can help detect those at risk for developing severe disease. A longer duration of amphotericin, combined with a more aggressive surgical approach in selected cases, may lead to better long-term outcomes.


Assuntos
COVID-19 , Mucormicose , Seios Paranasais , Humanos , Mucormicose/diagnóstico por imagem , Hemoglobinas Glicadas , COVID-19/diagnóstico por imagem , Seios Paranasais/diagnóstico por imagem , Gravidade do Paciente
7.
Ann Afr Med ; 21(3): 296-298, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36204920

RESUMO

Familial amyloid polyneuropathy (PN), also known as amyloid transthyretin (TTR)-PN is an autosomal dominant adult-onset fatal disease, if not treated. It occurs due to mutations in (TTR) gene which leads to a faulty TTR protein which folds up to form amyloid and gets deposited mainly on nerves and causes length-dependent PN and autonomic dysfunction. We report a case of a 45-year-old female who presented with symptoms of painful peripheral neuropathy for 5 months, a history of deafness for 5 years, and cardiac pacemaker implantation 2 years ago for complete heart block. She denied any symptoms of autonomic dysfunction. Her brother with similar symptoms died of cardiac arrest at the age of 50 years. Clinical examination was suggestive of symmetrical sensorimotor PN. The nerve conduction study was suggestive of axonal sensorimotor PN. Abdominal fat biopsy was negative for amyloid. Sural nerve biopsy was suggestive of amyloid neuropathy. Genetic analysis showed c. 165G > T mutation encoding amino acid p. Lys55Asn on exon-4 of TTR gene. This mutation has not been reported from India.


Résumé La polyneuropathie amyloïde familiale (NP), également connue sous le nom de transthyrétine amyloïde (TTR) -PN, est une maladie mortelle autosomique dominante de l'adulte, si elle n'est pas traitée. Il se produit en raison de mutations du gène (TTR) qui conduisent à une protéine TTR défectueuse qui se replie pour former de l'amyloïde et se dépose principalement sur les nerfs et provoque une PN dépendante de la longueur et un dysfonctionnement autonome. Nous rapportons le cas d'une femme de 45 ans qui présentait des symptômes de neuropathie périphérique douloureuse depuis 5 mois, des antécédents de surdité depuis 5 ans et l'implantation d'un stimulateur cardiaque il y a 2 ans pour un bloc cardiaque complet. Elle a nié tout symptôme de dysfonctionnement autonome. Son frère présentant des symptômes similaires est décédé d'un arrêt cardiaque à l'âge de 50 ans. L'examen clinique évoquait une NP sensorimotrice symétrique. L'étude de la conduction nerveuse était évocatrice d'une NP sensorimotrice axonale. La biopsie de la graisse abdominale était négative pour l'amyloïde. La biopsie du nerf sural était évocatrice d'une neuropathie amyloïde. L'analyse génétique a montré c. Mutation 165G > T codant pour l'acide aminé p. Lys55Asn sur l'exon-4 du gène TTR. Cette mutation n'a pas été signalée en Inde. Mots clés: Neuropathie amyloïde familiale, tests génétiques, biopsie nerveuse, amylose à transthyrétine.


Assuntos
Neuropatias Amiloides Familiares , Adulto , Aminoácidos/genética , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/patologia , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Dor , Doenças do Sistema Nervoso Periférico , Pré-Albumina/genética , Pré-Albumina/metabolismo
8.
J Glob Infect Dis ; 14(2): 81-83, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35910819

RESUMO

Chikungunya is a common tropical viral infection in India. The majority of patients have limited systemic manifestations. Neurological manifestations of chikungunya may be due to direct viral infection or immune mediated. We present a case of a 45-year-old male who presented with acute onset paraplegia with diminution of vision in the right eye. A detailed evaluation revealed a diagnosis of chikungunya myeloradiculitis with viral keratitis. The patient was treated with steroids followed by intravenous immunoglobulin and had a good recovery.

9.
Bioresour Technol ; 352: 127030, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35314311

RESUMO

Sustainable and economical wastewater treatment forms a vital step towards long-term sustainability of petrochemical refineries and industries. An affordable solution to this challenge is to employ biowaste as the key consumable active component. This paper describes the synthesis and characterization of activated biochar derived from cow-dung, a readily available raw material in low-resource settings, and its application for adsorption of phenol, one of the major pollutants in industrial wastewater. Adsorption parameters are optimized by using response surface methodology. Phenol adsorption equilibrium and kinetics data are well fitted to Freundlich isotherm (R2 = 0.97) and pseudo-second-order model (R2 = 0.99), respectively. The maximal adsorption capacity (518.89 mg/g) was attained using the Langmuir isotherm model at pH 6.0. Negative values of thermodynamic parameters confirmed the spontaneity, feasibility, and exothermic behaviour of adsorption reaction. The results demonstrate that synthesized activated biochar showed an excellent phenol adsorption capacity of 98.8 %.


Assuntos
Fenol , Poluentes Químicos da Água , Adsorção , Animais , Bovinos , Carvão Vegetal/química , Feminino , Concentração de Íons de Hidrogênio , Cinética , Fenol/química , Fenóis/análise , Termodinâmica , Poluentes Químicos da Água/análise
10.
Dalton Trans ; 51(10): 3992-4009, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35174381

RESUMO

Herein, hierarchical sheet-like assemblies of interfacially coupled NiO/NiMoO4 (NNMO) nanocomposites are prepared by a simple and cost-effective one-step aqueous reflux method followed by post-thermal treatment. The reaction time is optimized for a high precursor yield and the homogeneity of the final product. The fabricated electrodes with varying amounts of active material and conducting carbon show better electrochemical activity for 50 : 50 weight ratio combinations as extrinsic pseudocapacitors. The optimized NNMO-3 electrode (obtained from the Ni-Mo hydroxide precursor during the 10 h reaction time) exhibits superior performance among all the tested nanocomposite electrodes like a high specific capacity of 649.8 C g-1 (1624.5 F g-1) and 73.5% retention of capacity after 2200 cycles at a specific current of 1.0 A g-1 along with satisfactory rate capability (42.5% retention after a ten-times increment in specific current), which may be attributed to the abundant electroactive sites due to the high bulk as well as electrochemically active surface area, mesoporous structure, and synergistic coupling between the optimum compositions of NiO and NiMoO4 within the sheet-like networks. Moreover, an aqueous asymmetric supercapacitor is assembled by employing NNMO-3 and activated carbon as the positive and negative electrodes, respectively, and exhibits a maximum specific capacity of 216.2 C g-1 (144.1 F g-1), specific energy of 45.0 W h kg-1 at a specific power of 750.0 W kg-1, promising rate capability of 58.5%, and good cycling stability with 86.2% capacitive retention after 2500 charge-discharge cycles. Based on the overall performance, we can infer that the NNMO-3 nanocomposite may be a promising electrode material for high-performance supercapacitor applications.

11.
Infect Genet Evol ; 43: 173-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27174088

RESUMO

Highly pathogenic avian influenza (HPAI) H5N1 viruses are a threat to poultry in Asia, Europe, Africa and North America. Here, we report isolation and characterization of H5N1 viruses isolated from ducks and turkeys in Kerala, Chandigarh and Uttar Pradesh, India between November 2014 and March 2015. Genetic and phylogenetic analyses of haemagglutinin gene identified that the virus belonged to a new clade 2.3.2.1c which has not been detected earlier in Indian poultry. The virus possessed molecular signature for high pathogenicity to chickens, which was corroborated by intravenous pathogenicity index of 2.96. The virus was a reassortant which derives its PB2 gene from H9N2 virus isolated in China during 2007-2013. However, the neuraminidase and internal genes are of H5N1 subtype. Phylogenetic and network analysis revealed that after detection in China in 2013/2014, the virus moved to Europe, West Africa and other Asian countries including India. The analyses further indicated multiple introductions of H5N1 virus in Indian poultry and internal spread in Kerala. One of the outbreaks in ducks in Kerala is linked to the H5N1 virus isolated from wild birds in Dubai suggesting movement of virus probably through migration of wild birds. However, the outbreaks in ducks in Chandigarh and Uttar Pradesh were from an unknown source in Asia which also contributed gene pools to the outbreaks in Europe and West Africa. The widespread incidence of the novel H5N1 HPAI is similar to the spread of clade 2.2 ("Qinghai-like") virus in 2005, and should be monitored to avoid threat to animal and public health.


Assuntos
Surtos de Doenças , Virus da Influenza A Subtipo H5N1/genética , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/epidemiologia , Filogenia , Vírus Reordenados/genética , África/epidemiologia , Animais , Galinhas/virologia , Patos/virologia , Monitoramento Epidemiológico , Europa (Continente)/epidemiologia , Expressão Gênica , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Índia/epidemiologia , Virus da Influenza A Subtipo H5N1/classificação , Vírus da Influenza A Subtipo H9N2/classificação , Influenza Aviária/transmissão , Influenza Aviária/virologia , Neuraminidase/genética , Filogeografia , Aves Domésticas/virologia , Vírus Reordenados/classificação , Perus/virologia
12.
J Nanosci Nanotechnol ; 10(6): 3998-4006, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20355405

RESUMO

We synthesized thin-multiwalled carbon nanotubes (t-MWCNTs) using Fe-Mo/MgO catalyst by citrate precursor method based on a simple sol-gel technique. Synthesis of high-quality t-MWCNTs with uniform diameters was achieved in large-scale by catalytic decomposition of methane over Fe-Mo/MgO catalyst prepared under Ar-atmosphere. The produced t-MWCNTs had the outer diameters in the range of 4-8 nm, with a Gaussian average diameter of 6.6 +/- 0.1 nm and wall numbers in the range of of 4-7 graphenes. The product yield of the as-synthesized t-MWCNTs was over 450% relative to the used Fe-Mo/MgO catalyst, and TGA showed purity about 85%. The t-MWCNTs showed the low turn-on field about 1.24 V/microm, corresponding to the current density of 0.1 microA/cm2, and the high emission Current density of 10 mA/cm2 at the applied electric field of 2.6 V/microm. The t-MWCNTs indicate good emission stability without any fluctuation of emission current through a lifetime measurement for 20 h. It was confirmed that the field emission performance of t-MWCNTs was similar to DWCNTs and the field emission stability of t-MWCNTs was similar to MWCNTs.

13.
J Inorg Biochem ; 98(11): 1667-77, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15522394

RESUMO

The success of modeling the active site function of oxomolybdoenzymes have been claimed generally on the basis of reactivity of the synthetic analogues towards PPh(3) or DMSO (dimethyl sulfoxide). Here it has been shown that the success of modeling the active site function of these enzymes may not be determined by the ability of a model to undergo oxotransfer with PPh(3) or DMSO (except for the modeling of DMSO reductase) and one should adhere to the criteria accepted by the bioinorganic community. A critical evaluation of two of those criteria which requires a synthetic analogue (a) should react with the enzyme substrate (b) should follow the same rate law as does the enzyme, has been presented in this paper. We have shown that the fulfillment of criterion (b) and the inhibition phenomena to that effect both are dictated by symphoria (from sympherin in Greek: the bringing together of reactants into the proper spatial relationship) on the basis of kinetic studies of the reactivity of enzyme substrate the HSO(3)(-) and its analogues (anions of oxyacids of phosphorous) towards a functional model sulfite oxidase [Bu(4)N](2)[Mo(VI)O(2)(mnt)(2)] (mnt(2-)=1,2-dicyanoethylenedithiolate) but with the caveat that the mechanistic inference drawn from such studies may not be the same as in the case of native enzyme. In view of this ambiguity it has been pointed out that the fulfillment of this criterion is not a definitive conclusion towards our understanding of the structure-function relationship of an enzyme and, therefore, the criterion of a 'structural analogue' and 'functional analogue' have been revised subject to an amendment of criterion (a) to include substrate analogues. It has also been shown for the first time on the basis of kinetic studies that the effect of medium can lead to substrate - inhibitor type dualism and hence the effect of medium is also a factor that can play a key role for the success of modeling the active site function of an enzyme. Here we also provide the details of the inhibition mechanisms proposed in our earlier report with an indirect proof to that effect.


Assuntos
Oxirredutases/metabolismo , Sítios de Ligação , Indicadores e Reagentes , Proteínas Ferro-Enxofre , Cinética , Modelos Biológicos , Molibdênio/metabolismo , Nitrato Redutase , Nitrato Redutases , Oxirredutases/química , Oxirredutases atuantes sobre Doadores de Grupo Enxofre , Espectrofotometria , Xantina Oxidase
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