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1.
Haemophilia ; 30(2): 410-418, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38343110

RESUMEN

INTRODUCTION: Various risk factors for inhibitor development in haemophilia A (HA) have been described but Indian data remains scanty. AIM: We aimed to evaluate the genetic changes in Indian HA-patients that are associated with the development of inhibitors. METHODS: All HA-patients with inhibitors who availed coagulation-laboratory services from January-2015 till December-2021 and had their samples preserved for DNA extraction were included in this study. An equal number of severity-matched HA patients without inhibitors were also included as controls. Intron 22 and intron 1 inversions in Factor VIII gene were identified using inverse-shifting-PCR. Inversion-negative patients were further assessed by targeted NGS, MLPA. RESULTS: Thirty HA-patients with inhibitors were identified. All had severe-HA. Thirty severe-HA-patients without inhibitors were also included as controls. Intron 22 inversion (63.3%) and large deletions (15%) were the commonest variants identified. There was no difference in genetic variants in patients with low and high titre inhibitors. A3, A2 and C2 were the most common domains involved in inversion-negative patients with inhibitors. However, there was no significant difference in domain involvement among inversion-negative patients with and without inhibitors. Seven novel-variants were identified, including three large deletions, one large duplication and two nonsense variants in inhibitor-positive patients, and one frameshift variant in inhibitor-negative patient. After adjusting for clinical risk-factors, large deletions were independently associated with the presence of inhibitors [aOR:6.1 (1.41-56.3)]. CONCLUSION: Intron 22 inversions are the commonest variant in Indian patients with severe-HA. Large deletions predispose to inhibitor development independent of clinical risk factors.


Asunto(s)
Hemofilia A , Humanos , Hemofilia A/genética , Estudios de Cohortes , Factor VIII/genética , Estudios de Asociación Genética , Intrones , Inversión Cromosómica , Genotipo , Fenotipo , Mutación
2.
Water Sci Technol ; 89(3): 513-528, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38358486

RESUMEN

In the current study, a novel methylene blue (MB)-based colorimetric method for a quick, inexpensive, and facile approach for the determination of fouling intensity of reverse osmosis (RO) membrane has been reported. This technique is based on the interaction of MB with the organic foulants and shows the corresponding change in the colour intensity depending on the severity of fouling. The organic foulants, such as albumin, sodium alginate, and carboxymethyl cellulose (CMC), were chosen as model foulants, and the membranes were subjected to foul under extreme fouling conditions. The fouled membranes underwent an MB treatment followed by image-processing analyses. The severity of surface fouling of membranes was evaluated in terms of fouling intensity and correlated with the corresponding decline of permeate flux. The maximum fouling intensity of the albumin, sodium alginate, and CMC sodium were found to be 8.83, 23.38, and 9.19%, respectively, for the definite concentration of foulants. The physico-chemical interactions of the given foulants and MB were confirmed by changes in zeta potentials and increased sizes of the foulant by the dynamic light scattering technique. The surface fouling over the membrane surface was confirmed by the characterization of membranes.


Asunto(s)
Colorimetría , Azul de Metileno , Albúminas , Alginatos , Carboximetilcelulosa de Sodio , Ósmosis
3.
Haemophilia ; 29(2): 591-599, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36571800

RESUMEN

INTRODUCTION: Inherited Factor VII (FVII) deficiency is commonest among the rare bleeding disorders. A small number of patients present in infancy with severe bleeding, and many may remain asymptomatic but detected before surgery/invasive procedures. Genetic testing may be helpful in predictive testing/prenatal diagnosis in severe cases. AIM: Characterisation of clinical and genotypic spectrum of patients with inherited FVII deficiency. METHODS: Retro-prospectively, 35 cases with prolonged prothrombin time and FVII activity (FVII:C) <50 IU/dl were subjected to targeted resequencing. After in-silico analysis, variant/s were validated by Sanger sequencing in index cases and family members. Haplotype analysis was done for F7 polymorphisms. RESULTS: Severe FVII deficiency was found in 50% of patients (FVII:C ≤1 IU/dl), and 42.9% were asymptomatic. Clinical severity assessment revealed 17% severe, 17% moderate and 22.9% patients with mild bleeds. FVII levels ranged from .3 to 38 IU/dl. Molecular analysis revealed variants in 30/35 cases, of which 17 were homozygous, 10 were compound heterozygous and 3 were heterozygous. Twelve genetic variants were identified, one promoter variant c.-30A>C; seven missense (c.215C>G, c.244T>C, c.253G>C, c.904G>A, c.961C>T, c.1109G>T, c.1211G>A), two deletions (c.21delG, c.868_870delATC), and one each of nonsense c.634C>T and splice-site variant c.316+1G>A. Recurrent variants c.1109G>T and c.215C>G were found in 17 and 8 cases, 12 of the former cases were homozygous. They had the same haplotype, indicating the founder effect in North Indians. CONCLUSION: This is the largest cohort of FVII genotyping from India, confirming heterogeneity in terms of clinical manifestations, FVII activity and zygosity of the variants with a limited genotypic phenotypic correlation.


Asunto(s)
Trastornos de la Coagulación Sanguínea , Deficiencia del Factor VII , Humanos , Efecto Fundador , Mutación , Deficiencia del Factor VII/diagnóstico , Deficiencia del Factor VII/genética , Factor VII/genética , Hemorragia
4.
Environ Res ; 231(Pt 2): 116151, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37196695

RESUMEN

Parthenium hysterophorus, one of the seven most hazardous weeds is widely known for its allergic, respiratory and skin-related disorders. It is also known to affect biodiversity and ecology. For eradication of the weed, its effective utilization for the successful synthesis of carbon-based nanomaterial is a potent management strategy. In this study, reduced graphene oxide (rGO) was synthesized from weed leaf extract through a hydrothermal-assisted carbonization method. The crystallinity and geometry of the as-synthesized nanostructure are confirmed from the X-ray diffraction study, while the chemical architecture of the nanomaterial is ascertained through X-ray photoelectron spectroscopy. The stacking of flat graphene-like layers with a size range of ∼200-300 nm is visualized through high-resolution transmission electron microscopy images. Further, the as-synthesized carbon nanomaterial is advanced as an effective and highly sensitive electrochemical biosensor for dopamine, a vital neurotransmitter of the human brain. Nanomaterial oxidizes dopamine at a much lower potential (0.13 V) than other metal-based nanocomposites. Moreover, the obtained sensitivity (13.75 and 3.31 µA µM-1 cm-2), detection limit (0.6 and 0.8 µM), the limit of quantification (2.2 and 2.7 µM) and reproducibility calculated through cyclic voltammetry/differential pulse voltammetry respectively outcompete many metal-based nanocomposites that were previously used for the sensing of dopamine. This study boosts the research on the metal-free carbon-based nanomaterial derived from waste plant biomass.


Asunto(s)
Carbono , Dopamina , Humanos , Dopamina/química , Reproducibilidad de los Resultados , Técnicas Electroquímicas/métodos , Metales , Extractos Vegetales
5.
Environ Res ; 229: 115922, 2023 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-37086886

RESUMEN

The inflated demand for plastic products has led to tremendous rise in plastic debris in different environmental matrices, thereby resulting in plastic pollution. This affects plants, animals, and even humans, as microplastics can enter the food chain and cause several health implications. Microplastics are the small plastic particles (size below 5 mm) that are largely debated nowadays owing to their environmental risk assessment. Their potential to interact with other toxic contaminants, their tendency to be ingested or taken up by living organisms and their longevity is a serious threat to our environment. However, despite wealth of recent information, still there is a gap, particularly in eco-toxicology studies, fate, prevalence and feasible solutions to cope up with the menace of microplastics pollution. This review unravels the environmental fate and behaviour of microplastics as well as their global distribution in the marine and terrestrial environment. Furthermore, we aim to contribute to the international debate on the microplastics global paradigm. We briefly suggest sustainable solutions and recommendations to achieve future research goals on microplastics. Our review reveals some of the newest biological (green algae and modified sponges) and physical (nano-particles and membrane treatment) remediation solutions to eradicate microplastics from different types of environment. This review presents a critical evaluation of the state of knowledge of micro-plastics and suggested some recommendations which can help in identifying some important key questions for future research.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Animales , Humanos , Microplásticos/toxicidad , Plásticos/toxicidad , Prevalencia , Contaminantes Químicos del Agua/análisis , Contaminación Ambiental , Monitoreo del Ambiente , Ecosistema
6.
Environ Res ; 217: 114844, 2023 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-36403653

RESUMEN

Poly- and perfluoroalkyl substances (PFAS) are a class of emerging organic contaminants that are impervious to standard physicochemical treatments. The widespread use of PFAS poses serious environmental issues. PFAS pollution of soils and water has become a significant issue due to the harmful effects of these chemicals both on the environment and public health. Owing to their complex chemical structures and interaction with soil and water, PFAS are difficult to remove from the environment. Traditional soil remediation procedures have not been successful in reducing or removing them from the environment. Therefore, this review focuses on new phytoremediation techniques for PFAS contamination of soils and water. The bioaccumulation and dispersion of PFAS inside plant compartments has shown great potential for phytoremediation, which is a promising and unique technology that is realistic, cost-effective, and may be employed as a wide scale in situ remediation strategy.


Asunto(s)
Fluorocarburos , Contaminantes Químicos del Agua , Biodegradación Ambiental , Fluorocarburos/análisis , Agua , Bioacumulación , Suelo/química , Contaminantes Químicos del Agua/análisis
7.
Mol Vis ; 27: 480-493, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34497454

RESUMEN

Glaucoma a debilitating disease, is globally the second most common kind of permanent blindness. Primary open-angle glaucoma (POAG) is its most prevalent form and is often linked with alterations in the myocilin gene (MYOC). MYOC encodes the myocilin protein, which is expressed throughout the body, but primarily in trabecular meshwork (TM) tissue in the eyes. TM is principally involved in regulating intraocular pressure (IOP), and elevated IOP is the main risk factor associated with glaucoma. The myocilin protein's function remains unknown; however, mutations compromise its folding and processing inside TM cells, contributing to the glaucoma phenotype. While glaucoma is a complex disease with various molecules and factors as contributing causes, the role played by myocilin has been the most widely studied. The current review describes the present understanding of myocilin and its association with glaucoma and aims to shift the focus toward developing targeted therapies for treating glaucoma patients with variations in MYOC.


Asunto(s)
Proteínas del Citoesqueleto/fisiología , Proteínas del Ojo/fisiología , Glaucoma de Ángulo Abierto/fisiopatología , Glicoproteínas/fisiología , Humanos , Presión Intraocular/fisiología , Terapia Molecular Dirigida , Malla Trabecular/metabolismo
8.
Hemoglobin ; 45(5): 338-340, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35144518

RESUMEN

Hyperunstable hemoglobins (Hbs) are challenging to diagnose and may be missed on conventional hemolytic anemia work-up. Here, we report the case of a 2-year-old Indian boy with infancy-onset severe hemolytic anemia. Its etiology was revealed by targeted next-generation sequencing (NGS) to be the rare Hb Mizuho (HBB: c.206T>C). This variant had been missed on the initial routine laboratory investigations (heat and isopropanol tests for unstable Hbs) owing to its hyperunstable nature.


Asunto(s)
Anemia Hemolítica , Hemoglobinas Anormales , Anemia Hemolítica/diagnóstico , Anemia Hemolítica/genética , Pueblo Asiatico , Preescolar , Hemoglobinas Anormales/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino
9.
Beilstein J Org Chem ; 17: 1392-1439, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34194579

RESUMEN

Double-headed nucleoside monomers have immense applications for studying secondary nucleic acid structures. They are also well-known as antimicrobial agents. This review article accounts for the synthetic methodologies and the biological applications of double-headed nucleosides.

12.
J Org Chem ; 84(5): 2786-2797, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30693780

RESUMEN

The rhodium/O2 system-catalyzed distal C(sp2)-H olefination of quinoline N-oxides is developed. Molecular oxygen has been explored as an economic and clean oxidant, an alternative to inorganic oxidants. A wide substrate scope with respect to quinoline N-oxides and olefins (activated acrylates and styrenes; unactivated aliphatic olefins) demonstrates the robustness of the developed catalytic method. Interestingly, 2-substituted quinoline N-oxides also afforded good yields of the corresponding C8-olefinated products. Kinetic isotope studies and deuterium-labeling experiments have been performed to understand the preliminary mechanistic pathway. The applicability of the developed method is demonstrated by utilizing natural product-derived substrates and by converting the C8-olefinated quinoline N-oxides into various other useful molecules.

13.
J Org Chem ; 84(17): 11323-11334, 2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31393719

RESUMEN

Herein we report, a single-pot multistep conversion of inactivated carboxylic acids to various N-containing compounds using a common synthetic methodology. The developed methodology rendered the use of carboxylic acids as a direct surrogate of primary amines, for the synthesis of primary ureas, secondary/tertiary ureas, O/S-carbamates, benzoyl ureas, amides, and N-formyls, exploiting the Curtius reaction. This approach has a potential to provide a diversified library of N-containing compounds, starting from a single carboxylic acid, based on the selection of the nucleophile.

14.
J Org Chem ; 84(20): 12871-12880, 2019 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-31257883

RESUMEN

A highly efficient and regioselective Rh(III)-catalyzed protocol for C8-bromination and amidation of quinoline N-oxide was developed. The transformation was found to be successful up to gram scale with excellent functional group tolerance and wide substrate scope. The mechanistic study revealed five-membered rhodacycle with quinoline N-oxide as a key intermediate for regioselective C8-functionalization. In addition, NFSI (N-fluorobis(phenylsulfonyl)-imide) was explored as an amidating reagent for C8-amidation of quinoline N-oxide for the first time.

15.
J Org Chem ; 83(20): 12702-12710, 2018 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-30211555

RESUMEN

Here, a facile and efficient protocol for the synthesis of 3-hydroxyquinolin-8-yl propanoates via Rh(III)-catalyzed C(8)-H activation of 2-substituted quinolines has been developed. The reaction proceeds via C(8)-H activation, functionalization with acrylates, followed by intramolecular migration of the oxygen atom from quinoline N-oxides to the acrylate moiety. In this approach, N-oxide plays a dual role of a traceless directing group as well as a source of an oxygen atom for hydroxylation. This catalytic method involves simultaneous formation of new C-C and C-O bonds and is applicable only for C2-substituted quinolines. A catalytically competent five-membered rhodacycle has been characterized, thus revealing a key intermediate in the catalytic cycle. In silico docking studies against Falcipan-2 have revealed that 3a, 3b, 3g, and 3m have better scores. In vitro evaluation of selected compounds against CQ-sensitive pf3D7 and CQ-resistant pfINDO strains provided evidence that 3d (IC50 13.3 µM) and 3g (IC50 9.5 µM) had good promise against Plasmodium falciparum in the in vitro culture. Compound 3g was found to be the most potent on the basis of both in vitro antiplasmodial activity [IC50 9.5 µM ( Pf3D7) and 11.9 µM ( PfINDO), resistance index 1.25] and in silico studies.


Asunto(s)
Antimaláricos/síntesis química , Antimaláricos/farmacología , Quinolinas/síntesis química , Quinolinas/farmacología , Rodio/química , Catálisis , Óxidos N-Cíclicos/química , Cisteína Endopeptidasas/metabolismo , Evaluación Preclínica de Medicamentos/métodos , Simulación del Acoplamiento Molecular , Estructura Molecular , Plasmodium falciparum/efectos de los fármacos , Unión Proteica , Relación Estructura-Actividad
17.
Org Biomol Chem ; 14(9): 2613-7, 2016 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-26846299

RESUMEN

A catalyst/solvent-free, one-pot and operationally simple method for the synthesis of quinoline-substituted α-hydroxy carboxylic derivatives by the hydroxyheteroarylation of olefins with quinoline N-oxides is reported. The reaction features a high atom-economy, mild and reagent/solvent-free conditions, broad substrate scope and good selectivity with high yields. A preliminary mechanistic study to shed light into the reaction pathway was also carried out.

18.
J Phys Chem A ; 120(33): 6563-74, 2016 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-27486828

RESUMEN

The effect of solvent polarity and micellar headgroup on a newly designed imidazolium based ionic liquid (IL) conjugated with naphthalene, 1,2-dimethyl-3-((6-(octyloxy)naphthalen-2-yl)methyl)-1H-imidazol-3-ium chloride (IN-O8-Cl), was studied using steady state and time-resolved fluorescence techniques. We observed that the dipole moment in the excited state is remarkably higher than the ground state. The effect of micellar surface charge on the photophysics of IN-O8-Cl in aqueous phase at room temperature was investigated. Formation of premicellar aggregates in sodium dodecylsulfate (SDS) was perceived; further the microenvironment of IN-O8-Cl was examined using steady-state fluorescence spectroscopy. Micropolarity of the micellar environment of SDS was found to be lower than that of cetyltrimethylammonium bromide (CTAB) and triton X-100 (TX100) following the order SDS < TX-100 < CTAB. The binding constant (Kb) and edge excitation red shift (EERS) from the emission maximum suggest that the probe binds strongly to the micelles. Multiexponential behavior was observed in time-resolved fluorescence lifetime studies in all micellar environments. We have observed an increase in rotational correlation time as we move from pure aqueous phase to solution containing surfactants of different head charge. Varieties of spectral parameters were used to justify the region in which the probe is present. The experimentally obtained dipole moment data were justified and explained by the DFT calculations of the electronic properties of IN-O8-Cl molecules in gas phase and in selected solvents.


Asunto(s)
Imidazoles/química , Líquidos Iónicos/química , Naftalenos/química , Teoría Cuántica , Micelas , Solventes/química , Espectrometría de Fluorescencia , Agua/química
20.
ACS Appl Mater Interfaces ; 16(6): 7097-7111, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38296332

RESUMEN

The incorporation of cerium-zinc bimetallic oxide (CeZnOx) nanostructures in sulfonated poly(2,6-dimethyl-1,4-phenylene oxide) (SPPO) membranes holds promise in an enhanced and durable fuel cell performance. This investigation delves into the durability and efficiency of SPPO membranes intercalated with CeZnOx nanostructures by varying the filler loading of 1, 2, and 3% (w/w). The successful synthesis of CeZnOx nanostructures by the alkali-aided deposition method is confirmed by wide-angle X-ray diffraction spectroscopy (WAXS), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) analyses. CeZnOx@SPPO nanocomposite membranes are fabricated using a solution casting method. The intricate interplay of interfacial adhesion and coupling configuration between three-dimensional CeZnOx and sulfonic moieties of the SPPO backbone yields an enhancement in the bound water content within the proton exchange membranes (PEMs). This constructs simultaneously an extensive hydrogen bonding network intertwined with the proton transport channels, thereby elevating the proton conductivity (Km). The orchestrated reversible redox cycling involving Ce3+/Ce4+ enhances the quenching of aggressive radicals, aided by Zn2+, promoting oxygen deficiency and Ce3+ concentration. This synergistic efficacy ultimately translates into composite PEMs characterized by a mere 4% mass loss and a nominal 6% decrease in Km after rigorous exposure to Fenton's solution. Remarkably, an improved power density of 403.2 mW/cm2 and a maximum current density of 1260.6 mA/cm2 were achieved with 2% loading of CeZnOx (SPZ-2) at 75 °C and 100% RH. The fuel cell performance of SPZ-2 is 74% higher than its corresponding pristine SPPO membrane.

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