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1.
Small ; 19(44): e2303340, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37386778

RESUMO

2D graphene the most investigated structures from nanocarbon family studied in the last three decades. It is projected as an excellent material useful for quantum computing, artificial intelligence, and next generation advanced technologies. Graphene exists in several forms and its extraordinary thermal, mechanical, and electronic properties, principally depend on the kind of perfection of the hexagonal atomic lattice. Defects are always considered as undesired components but certain defects in graphene could be an asset for electrochemistry and quantum electronics due to the engineered electronclouds and quantum tunnelling. The authors carefully discuss the Stone-Wales imperfections in graphene and its derivatives comprehensively. A specific emphasis is focused on the experimental and theoretical aspects of the Stone-Wales defects in graphene with respect to structure-property relationships. The corroboration of extrinsic defects like external atomic doping, functionalization, edge distortion in the graphene consisting of Stone-Wales imperfections, which are very significant in designing graphene-based electronic devices, are summarized.

2.
Microb Pathog ; 135: 103634, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31325568

RESUMO

BACKGROUND: Research indicates that Helicobacter pylori can inflict severe histological damage through the modulation of host-related genes. The current study investigated the effect of H. pylori genotypes in the outcome of disease, and the expression of anti-apoptotic related genes, COX-1, COX-2, and iNOS genes in benign, pre-malignant, and malignant lesions of gastric carcinogenesis. MATERIALS AND METHODS: Tissue samples from H. pylori positive patients were graded based on the genotype of the infected H. pylori strain. Expression of COX-1, COX-2 and iNOS was assessed using a combination of real-time PCR and immunohistochemistry. RESULTS: Gene expression studies confirmed that COX-2 and iNOS expression was highly and selectively induced in epithelium with premalignant changes such as atrophic conditions, metaplasia and dysplasia, suggesting an important role of these genes in the sequence to gastric carcinoma of the intestinal type. Furthermore, the expression of COX-2 and iNOS was also dependent on the genotype of H. pylori and subjects with genotype-1 exhibited significantly higher expressions of COX-2 and iNOS compared to other genotypes. Comparison of the expression levels among infected and uninfected individuals demonstrated significant difference in the expression pattern of COX-2 gene whereas iNOS expression was found only in subjects infected H. pylori (p < 0.001). Immunohistochemical staining showed 1.5619 folds higher propensity of COX-2 and 3.2941 folds higher intensity of iNOS expression in subjects infected with H. pylori genotype 1. CONCLUSION: The up-regulation of COX-2 and iNOS was associated with the genotype of the H. pylori strain and the presence of certain genotype may greatly affect early events during carcinogenesis.


Assuntos
Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/metabolismo , Expressão Gênica , Infecções por Helicobacter/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Adenocarcinoma , Adulto , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 2/genética , Mucosa Gástrica/patologia , Gastrite , Gastrite Atrófica , Genótipo , Infecções por Helicobacter/genética , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Humanos , Imuno-Histoquímica , Metaplasia , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo II/genética , RNA Mensageiro/metabolismo , Neoplasias Gástricas/patologia , Regulação para Cima
3.
Malar J ; 14: 65, 2015 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-25879738

RESUMO

BACKGROUND: Development of resistance against the frontline anti-malarial drugs has created an alarming situation, which requires intensive drug discovery to develop new, more effective, affordable and accessible anti-malarial agents. METHODS: Inspired by their ethnobotanical reputation for being effective against febrile diseases, antiplasmodial potential of ethyl acetate extracts (EAE) and methanol extracts (ME) of 17 medicinal plants collected from the Eastern Ghats of South India and Buchpora, North India were explored against Plasmodium falciparum in vitro using the SYBR Green assay. The results were validated both by confirmation that the fall in fluorescence signal was not due to quenching effects mediated by phytochemical extracts and by Giemsa-stained microscopy. RESULTS: Using EAE or ME, promising antiplasmodial activity (IC50 Pf3D7 ≤ 20 µg/ml), was seen in Aerva lanata (Whole aerial parts-EAE), Anisomeles malabarica (Leaf-EAE), Anogeissus latifolia (bark-EAE), Cassia alata (leaves-EAE), Glycyrrhiza glabra (root-EAE), Juglans regia (seed-ME), Psidium guajava (leaf-ME and EAE) and Solanum xanthocarpum (Whole aerial parts-EAE). EAEs from leaves of Couroupita guianensis, Euphorbia hirta, Pergularia daemia, Tinospora cordifolia and Tridax procumbens as also ME from Ricinus communis (leaf and seed) showed good antiplasmodial activity (Pf 3D7 IC50 21 - 40 µg/ml). Moderate activity (Pf 3D7 IC50: 40-60 µg/mL) was shown by the leaf EAEs of Cardiospermum halicacabum, Indigofera tinctoria and Ricinus communis while the remaining extracts showed marginal (Pf 3D7 IC50 60 to >100 µg/ml) activities. The promising extracts showed good resistance indices (0.41 - 1.4) against the chloroquine resistant INDO strain of P. falciparum and good selectivity indices (3 to > 22.2) when tested against the HeLa cell line. CONCLUSION: These results provide validity to the traditional medicinal usage of some of these plants and further make a case for activity-guided purification of new pharmacophores against malaria.


Assuntos
Antimaláricos/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Eritrócitos/parasitologia , Células HeLa , Humanos , Índia , Extratos Vegetais/toxicidade
4.
Mitochondrion ; 68: 114-124, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36509340

RESUMO

The magnitude of variations in the level of circulating mitochondrial (cir-mtDNA) and nuclear DNA (cir-ncDNA) in different diseases has indicated the need for investigating a discriminative approach for evaluating their diagnostic significance. This study reports a typical in-house process for extracting both types of cir-DNAs from a single plasma sample and assessed their usefulness in discriminating type 2 diabetes mellitus patients from healthy individuals to eliminate the prevailing dispute about their discriminative role and improve their diagnostic value. This approach offers a more precise and valuable tool for distinguishing the impact of cir-mtDNA from cir-ncDNA in diagnostic implications.


Assuntos
Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Patologia Molecular , Mitocôndrias/genética , DNA Mitocondrial/genética
5.
Front Oncol ; 13: 1110909, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37152005

RESUMO

The toxic effects of chemotherapy drugs on normal tissues are still a major limiting factor in cancer treatment. In this paper, we report a metal-organic framework (Zn-Co ZIF) with chitosan-coated outer layer as a carrier for the drug adriamycin hydrochloride (DOX), a treatment for liver cancer, as a novel anti-cancer nanodrug-enhanced carrier. Gold nanoparticles, a good photothermal conversion agent, were combined with the target SH-RGD during surface functionalisation to prepare Zn-Co ZIF@DOX-CS-Au-RGD (ZD-CAR), a nanoplatform with good photothermal conversion properties and targeting for combined liver cancer therapy. ZD-CAR was developed after RGD accurately targeted the tumour and entered the tumour microenvironment (TME), it cleaves and releases the liver cancer therapeutic agent (DOX) in a weak acidic environment to effectively kill tumour cells. The metal skeleton cleavage releases Co2+, which catalyzes the production of oxygen from H2O2 to alleviate the tumour hypoxic environment. The dissolved oxygen could reach 14 mg/L after adding 80 mg/mL of ZD-CAR. Meanwhile, gold nanoparticles could convert light energy into heat energy under 808 NIR irradiation to induce local superheating and kill tumour cells. In summary, this study developed a nanoplatform that combines chemo-photothermal-targeted therapy. It has shown good therapeutic effeciency in cellular experiments and performance tests and has promising applications in anti-cancer therapy.

6.
Nanomaterials (Basel) ; 13(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36903705

RESUMO

The slow kinetics of the oxygen evolution reaction (OER) is one of the significant reasons limiting the development of electrochemical hydrolysis. Doping metallic elements and building layered structures have been considered effective strategies for improving the electrocatalytic performance of the materials. Herein, we report flower-like nanosheet arrays of Mn-doped-NiMoO4/NF (where NF is nickel foam) on nickel foam by a two-step hydrothermal method and a one-step calcination method. The doping manganese metal ion not only modulated the morphologies of the nickel nanosheet but also altered the electronic structure of the nickel center, which could be the result of superior electrocatalytic performance. The Mn-doped-NiMoO4/NF electrocatalysts obtained at the optimum reaction time and the optimum Mn doping showed excellent OER activity, requiring overpotentials of 236 mV and 309 mV to drive 10 mA cm-2 (62 mV lower than the pure NiMoO4/NF) and 50 mA cm-2 current densities, respectively. Furthermore, the high catalytic activity was maintained after continuous operation at a current density of 10 mA cm-2 of 76 h in 1 M KOH. This work provides a new method to construct a high-efficiency, low-cost, stable transition metal electrocatalyst for OER electrocatalysts by using a heteroatom doping strategy.

7.
Inflamm Res ; 61(4): 359-65, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22193858

RESUMO

OBJECTIVE: The present study was designed to investigate the role of X-ray cross-complementing group 1 (XRCC1) and apurinic/apyrimidinic endonuclease 1 (APE1) polymorphisms in apoptosis and the risk of ulcerative colitis (UC). MATERIALS AND METHODS: Blood samples from 384 unrelated subject (age range 18-65 years; 171 with UC, 213 healthy controls) were collected after colonoscopy. Genomic DNA was isolated and genotyped for XRCC1 Arg399Gln and APE1 Asp148Glu using a confronting two-pair primers polymerase chain reaction. Apoptosis and intracellular reactive oxygen species (ROS) levels in peripheral blood mononuclear cells were measured using annexin-V and H(2)DCFDA assay, respectively. RESULTS: The frequency of genotype Arg399Gln (heterozygous) of XRCC1 gene was significantly higher in patients with UC than the controls (odds ratio [OR] 1.73; 95% confidence interval [CI] 1.13-2.64; p = 0.01). Similarly the genotypic frequency of APE1 Asp148Glu showed statistically significant incidence among UC subjects (OR 1.54; 95% CI 1.02-2.33; p = 0.04). Polymorphism in XRCC1 Arg399Gln and APE1 Asp148Glu together considerably increased the risk of UC (OR 2.303; 95% CI 1.43-3.69; p = 0.0007). ROS levels were high in UC subjects compared with controls (p = 0.01). CONCLUSION: Polymorphisms in XRCC1 Arg399Gln and APE1 Asp148Glu significantly increased the rate of apoptosis and risk of ulcerative colitis.


Assuntos
Apoptose/genética , Colite Ulcerativa/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Proteínas de Ligação a DNA/genética , Adolescente , Adulto , Idoso , Colite Ulcerativa/metabolismo , Feminino , Predisposição Genética para Doença , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Espécies Reativas de Oxigênio/metabolismo , Risco , Proteína 1 Complementadora Cruzada de Reparo de Raio-X , Adulto Jovem
8.
Nanomaterials (Basel) ; 12(11)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35683662

RESUMO

Hydrogen is regarded as a key renewable energy source to meet future energy demands. Moreover, graphene and its derivatives have many advantages, including high electronic conductivity, controllable morphology, and eco-friendliness, etc., which show great promise for electrocatalytic splitting of water to produce hydrogen. This review article highlights recent advances in the synthesis and the applications of graphene-based supported electrocatalysts in hydrogen evolution reaction (HER). Herein, powder-based and self-supporting three-dimensional (3D) electrocatalysts with doped or undoped heteroatom graphene are highlighted. Quantum dot catalysts such as carbon quantum dots, graphene quantum dots, and fullerenes are also included. Different strategies to tune and improve the structural properties and performance of HER electrocatalysts by defect engineering through synthetic approaches are discussed. The relationship between each graphene-based HER electrocatalyst is highlighted. Apart from HER electrocatalysis, the latest advances in water electrolysis by bifunctional oxygen evolution reaction (OER) and HER performed by multi-doped graphene-based electrocatalysts are also considered. This comprehensive review identifies rational strategies to direct the design and synthesis of high-performance graphene-based electrocatalysts for green and sustainable applications.

9.
ACS Omega ; 7(15): 12846-12855, 2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35474771

RESUMO

Development of a low cost, high activity, and stable nonprecious metal bifunctional catalyst for electrocatalytic water cracking is a hot topic and big challenge. In this paper, we prepared a nitrogen-doped carbon nanotube (NCNT)-enhanced three-dimensional self-supported electrocatalyst with CoP and Co2P coexistence by a two-step strategy of high-temperature carbonization and low-temperature phosphorylation. Furthermore, the induced three-dimensional carbon network skeleton facilitates rapid charge transfer. In addition, the active sites of the carbon foam (CF) are greatly increased by the construction of hollow structures. As a bifunctional electrocatalyst, CoP/Co2P/NCNT@CF exhibited excellent catalytic activity for both hydrogen evolution reaction and oxygen evolution reaction in alkaline media, requiring low overpotentials of 133 and 289 mV to obtain a current density of 10 mA cm-2, respectively. Additionally, the synthesized catalysts also exhibit good long-term stability, maintaining high catalytic activity after 20 h of continuous operation. We also confirmed the main driving force to improve the electron transfer between the heterostructures of Co and P by XPS spectra. The excellent electrocatalytic performance can be attributed to the close synergy between the highly active CoP/Co2P/NCNT and CF. This study provides a new strategy for the design of highly active bifunctional self-supporting electrocatalysts.

10.
Adv Sci (Weinh) ; 9(11): e2105770, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35174979

RESUMO

New materials are the backbone of their technology-driven modern civilization and at present carbon nanostructures are the leading candidates that have attracted huge research activities. Diamanes and diamanoids are the new nanoallotropes of sp3 hybridized carbon which can be fabricated by proper functionalization, substitution, and via Birch reduction under controlled pressure using graphitic system as a precursor. These nanoallotropes exhibit outstanding electrical, thermal, optical, vibrational, and mechanical properties, which can be an asset for new technologies, especially for quantum devices, photonics, and space technologies. Moreover, the features like wide bandgap, tunable thermal conductivity, excellent thermal insulation, etc. make diamanes and diamanoids ideal candidates for nano-electrical devices, nano-resonators, optical waveguides, and the next generation thermal management systems. In this review, diamanes and diamanoids are discussed in detail in terms of its historical prospect, method of synthesis, structural features, broad properties, and cutting-edge applications. Additionally, the prospects of diamanes and diamanoids for new applications are carefully discussed. This review aims to provide a critical update with important ideas for a new generation of quantum devices based on diamanes and diamanoids which are going to be an important topic in the future of carbon nanotechnology.

11.
ACS Omega ; 7(4): 3230-3239, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35128236

RESUMO

Production of snake foam based on p-nitro aniline (PNA) was considered fun in old-school chemistry laboratories. Herein, we report the fabrication of a new carbon nanomaterial from PNA-based foam. The resulting material, resembling graphene and consisting of nitrogen heteroatoms, is N-doped graphenelike nanostructures, and their morphology, structure, and stability are comprehensively examined using combined techniques including C-13 NMR spectroscopy, X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). An optimized route was also established for their large-scale production. Further experimental validation of them as a nanofiller in polymer [SEBS (20 wt %) and paraffin wax (80 wt %)]-based nanocomposites was carried out, and we found that the thermomechanical properties of the nanocomposites were synchronously improved, which was attributed to the enshrouding effect of the nanofiller to the polymer chains. Owing to their good thermomechanical property and low-cost feature, these new nanomaterials can be further explored as a promising candidate for applications in energy storage, catalysis, and CO2 capture.

12.
Asian Cardiovasc Thorac Ann ; 30(5): 524-531, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34494903

RESUMO

BACKGROUND: To maintain the patency and longevity of arteriovenous fistula, the availability of a venous segment with adequate diameter is important. In Indian population, many chronic kidney disease patients have poor caliber veins. The study aimed to evaluate the efficacy of hydrostatic dilatation versus Primary balloon angioplasty of small caliber cephalic veins of (≤2.5 mm) preoperatively in terms of patency rate and maturation time of arteriovenous fistula. METHODS: Patients (n = 80) with an end-stage renal disease requiring arteriovenous access surgery for hemodialysis with small caliber cephalic veins were randomized into two groups, i.e., hydrostatic dilatation and primary balloon angioplasty, each with 40 patients. All patients underwent a thorough clinical examination as well as duplex ultrasound vein mapping of both upper extremities. Patients were followed up for six months and primary patency, maturation time, and complications were noted. RESULTS: Immediate technical success with good palpable thrill was achieved in 97.5% of patients in the primary balloon angioplasty group and 87.5% in the hydrostatic dilatation group. The fistula maturation time in the primary balloon angioplasty group was 34.41 days and 46.18 days in the hydrostatic dilatation group. In the primary balloon angioplasty group, the primary patency of the fistula was 97.5% and 87.5% in the hydrostatic dilatation group, at six months. The arteriovenous fistula functioning rate was 77.5% in the hydrostatic dilatation group as compared to 92.5% in the primary balloon angioplasty group at six months. The incidence of surgical site infection was 5% in the primary balloon angioplasty group as compared to 10% in the hydrostatic dilatation group. CONCLUSION: Primary balloon angioplasty of small caliber cephalic veins (≤2.5 mm) performed prior to arteriovenous fistula creation for hemodialysis is a beneficial procedure.


Assuntos
Angioplastia com Balão , Fístula Arteriovenosa , Derivação Arteriovenosa Cirúrgica , Angioplastia com Balão/efeitos adversos , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/métodos , Dilatação , Humanos , Diálise Renal , Fatores de Tempo , Resultado do Tratamento , Grau de Desobstrução Vascular
13.
Scand J Infect Dis ; 42(4): 266-74, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20092379

RESUMO

Abstract We examined sodium selenite, an inorganic selenium supplement, for its ulcer healing properties and antimicrobial activity against gastric pathogen Helicobacter pylori. Minimum inhibitory concentrations (MIC) were determined using disk diffusion and flow cytometry. The studies were performed over a concentration range of 1 microg/ml to 500 microg/ml sodium selenite. Mild activity was seen at 10 microg/ml and 50 microg/ml, a moderate response at 100 microg/ml and strong response at 500 microg/ml with a MIC value of 10 microg/ml. The compound was found to be active at low pH without any resistance after 10 passages. Flow cytometry data showed a characteristic shift of the viability peak in comparison with the control, thereby confirming the bactericidal effects of sodium selenite. Sodium selenite administered in Wistar rats, pre-ulcerated with naproxen and infected with H. pylori, showed ulcer healing and anti-H. pylori activity at a concentration range of 10-50 microg/rat; however concentrations of 100 microg/rat and 500 microg/rat were found to be toxic in the in vivo studies. In conclusion, sodium selenite shows both ulcer healing and anti-H. pylori activity at a low concentration (10 microg/rat) without toxicity.


Assuntos
Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antiulcerosos/farmacologia , Antiulcerosos/uso terapêutico , Infecções por Helicobacter/tratamento farmacológico , Selenito de Sódio/farmacologia , Selenito de Sódio/uso terapêutico , Animais , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Antiulcerosos/administração & dosagem , Antiulcerosos/efeitos adversos , Helicobacter pylori/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Ratos , Ratos Wistar , Selenito de Sódio/administração & dosagem , Selenito de Sódio/efeitos adversos
14.
Inflammopharmacology ; 18(2): 59-64, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20143166

RESUMO

Persistent infection with Helicobacter pylori confers an increased risk of peptic ulceration and gastric adenocarcinoma. Reactive oxygen and nitrogen species play a crucial role in the progression from normal gastric mucosa to cancer. The aim of the present study was to investigate the plasma malondialdehyde and nitric oxide levels in H. pylori related gastroduodenal diseases and associate their levels with gastric pathology and genotypes of H. pylori. Malondialdehyde and nitric oxide levels in plasma samples of 250 subjects were spectrophotometrically determined. Subsequently, genotypic and histopathological assessment was performed in gastric biopsies obtained during endoscopy. The levels of MDA and NO exceeded in subjects infected with genotype-1 of Hp than those with other genotypes suggesting more precise interaction of highly virulent strains of Hp in eliciting severe tissue damage. In conclusion, the study demonstrates close relationship between the plasma malondialdehyde and nitric oxide levels, gastric histopathology and genotypes of H. pylori.


Assuntos
Gastroenteropatias/sangue , Gastroenteropatias/microbiologia , Infecções por Helicobacter/sangue , Helicobacter pylori/genética , Helicobacter pylori/patogenicidade , Malondialdeído/sangue , Óxido Nítrico/sangue , Adulto , Feminino , Gastrite/sangue , Gastrite/microbiologia , Gastrite/patologia , Gastrite Atrófica/sangue , Gastrite Atrófica/microbiologia , Gastrite Atrófica/patologia , Gastroenteropatias/patologia , Genótipo , Infecções por Helicobacter/genética , Infecções por Helicobacter/patologia , Helicobacter pylori/isolamento & purificação , Humanos , Intestinos/microbiologia , Intestinos/patologia , Masculino , Metaplasia/sangue , Metaplasia/microbiologia , Metaplasia/patologia , Pessoa de Meia-Idade , Neoplasias Gástricas/sangue , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia
15.
Nanomaterials (Basel) ; 10(10)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33081271

RESUMO

This review acmes the latest developments of composites of metal oxides/sulfide comprising of graphene and its analogues as electrode materials in the construction of the next generation of supercapacitors (SCs). SCs have become an indispensable device of energy-storage modes. A prompt increase in the number of scientific accomplishments in this field, including publications, patents, and device fabrication, has evidenced the immense attention they have attracted from scientific communities. These efforts have resulted in rapid advancements in the field of SCs, focusing on the development of electrode materials with features of high performance, economic viability, and robustness. It has been demonstrated that carbon-based electrode materials mixed with metal oxides and sulfoxides can perform extremely well in terms of energy density, durability, and exceptional cyclic stability. Herein, the state-of-the-art technologies relevant to the fabrication, characterization, and property assessment of graphene-based SCs are discussed in detail, especially for the composite forms when mixing with metal sulfide, metal oxides, metal foams, and nanohybrids. Effective synthetic methodologies for the nanocomposite fabrications via intercalation, coating, wrapping, and covalent interactions will be reviewed. We will first introduce some fundamental aspects of SCs, and briefly highlight the impact of graphene-based nanostructures on the basic principle of SCs, and then the recent progress in graphene-based electrodes, electrolytes, and all-solid-state SCs will be covered. The important surface properties of the metal oxides/sulfides electrode materials (nickel oxide, nickel sulfide, molybdenum oxide, ruthenium oxides, stannous oxide, nickel-cobalt sulfide manganese oxides, multiferroic materials like BaMnF, core-shell materials, etc.) will be described in each section as per requirement. Finally, we will show that composites of graphene-based electrodes are promising for the construction of the next generation of high performance, robust SCs that hold the prospects for practical applications.

16.
Polymers (Basel) ; 12(10)2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-33066184

RESUMO

The industrial advancement of high-performance technologies directly depends on the thermo-mechanical properties of materials. Here we give an account of a facile approach for the bulk production of a polyethylene terephthalate (PET)/polypropylene (PP)-based nanocomposite blend with Inorganic Fullerene Tungsten Sulfide (IF-WS2) nanofiller using a single extruder. Nanofiller IF-WS2 was produced by the rotary chemical vapor deposition (RCVD) method. Subsequently, IF-WS2 nanoparticles were dispersed in PET and PP in different loadings to access impact and their dispersion behavior in polymer matrices. As-prepared blend nanocomposites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), dynamic differential scanning (DSC), dynamic mechanical analysis (DMA), and X-ray diffraction (XRD). In this work, the tensile strength of the PP/PET matrix with 1% IF-WS2 increased by 31.8%, and the thermal stability of the sample PP/PET matrix with 2% increased by 18 °C. There was an extraordinary decrease in weight loss at elevated temperature for the nanocomposites in TGA analysis, which confirms the role of IF-WS2 on thermal stability versus plain nanocomposites. In addition, this method can also be used for the large-scale production of such materials used in high-temperature environments.

17.
World J Gastroenterol ; 12(44): 7136-42, 2006 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-17131475

RESUMO

AIM: to evaluate the antibacterial activity of Sapindus mukorossi (S. mukorossi) and Rheum emodi (R. emodi). METHODS: Powders of S. mukorossi and R. emodi were extracted successively with petroleum ether, benzene, chloroform and ethanol and were concentrated in vacuum. The disk diffusion method was used for in vitro studies and in vivo studies were performed on male Wister rats. Thirty resistant clinical isolates of H pylori, as determined by their antibiotic sensitivity patterns by E-test, along with two Gram +ve (S. aureus, B. subtilis) and two Gram -ve (E. coli, P. vugaris) organisms were screened for their susceptibility patterns against these extracts. RESULTS: In our screening, all 30 resistant isolates and the other four organisms (two Gram +ve S. aureus, B. subtilis and two Gram -ve, E. coli, P. vugaris) were sensitive to the test compounds. It was found that ethanol and chloroform extracts of S. mukorossi and ethanol and benzene extracts of R. emodi inhibited H pylori at very low concentrations. In the in vitro study, the isolates showed a considerable zone of inhibition at very low concentrations (10 mug/mL) for both the extracts. In the in vivo study, the H pylori infection was cleared with minimal doses of extracts of S. mukorossi (2.5 mg/mL) and R. emodi (3.0 mg/mL) given orally for seven days. CONCLUSION: We can conclude from this study that the extracts of S. mukorossi and R. emodi inhibited the growth of pylori in vitro and, in in vivo studies, the H pylori infection cleared within seven days at very low concentrations. We also found that H pylori did not acquire resistance against these herbal extracts even after 10 consecutive passages.


Assuntos
Antibacterianos/farmacologia , Helicobacter pylori/efeitos dos fármacos , Extratos Vegetais/farmacologia , Rheum/química , Sapindus/química , Animais , Antibacterianos/isolamento & purificação , Antibacterianos/uso terapêutico , Masculino , Testes de Sensibilidade Microbiana , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar , Úlcera Gástrica/tratamento farmacológico
18.
World J Gastroenterol ; 12(14): 2181-6, 2006 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-16610018

RESUMO

AIM: To investigate the presence of Helicobacter species by nested PCR of 16S rRNA genes followed by the presence of Helicobacter pylori (H pylori) 16S rRNA, ureA, cagA genes in bile obtained at endoscopic retrograde cholangio-pancreatography (ERCP) from 60 Indian subjects. METHODS: Sixty bile samples were obtained from patients diagnosed with various hepato-biliary diseases and control subjects at ERCP. PCR analysis was carried out using primers for Helicobacter genus 16S rRNA gene and H pylori (16S rRNA, ureA and cagA) genes. Gastric H pylori status was also assessed from biopsies obtained at endoscopy from patients with various hepato-biliary diseases and controls. The control group mainly consisted of subjects with gastric disorders. Sequencing analysis was performed to confirm that PCR products with 16S rRNA and cagA primers were derived from H pylori. RESULTS No Helicobacters were grown in culture from the bile samples. Helicobacter DNA was detected in bile of 96.7% and 6.6% of groups I and II respectively. Ten from group I were positive for 16S rRNA and ureA and 9 were positive for cagA gene. In contrast of the 2 from the control, 1 amplified with 16S rRNA, ureA and cagA primers used. The sequences of the 16S rRNA genes and cagA were 99% similar to Helicobacter pylori. CONCLUSION: Helicobacters are associated with the pathogenesis of various hepato-biliary disorders.


Assuntos
Bile/microbiologia , Doenças Biliares/microbiologia , DNA Bacteriano/análise , Helicobacter pylori/isolamento & purificação , Helicobacter/isolamento & purificação , Hepatopatias/microbiologia , Adulto , Idoso , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Colangiopancreatografia Retrógrada Endoscópica , Feminino , Helicobacter/genética , Helicobacter pylori/genética , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/genética
19.
World J Gastroenterol ; 11(43): 6815-22, 2005 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-16425389

RESUMO

AIM: To investigate the presence of the cag-pathogenicity island and the associated histological damage caused by strains with complete cag-PAI and with partial deletions in correlation to the disease status. METHODS: We analyzed the complete cag-PAI of 174 representative Helicobacter pylori (H pylori ) clinical isolates obtained from patients with duodenal ulcer, gastric ulcer, gastric cancer, and non-ulcer dyspepsia using eight different oligonucleotide primers viz cagA1, cagA2, cagAP1, cagAP2, cagE, cagT, LEC-1, LEC-2 spanning five different loci of the whole cag-PAI by polymerase chain reaction (PCR). RESULTS: The complete screening of the genes comprising the cag-PAI showed that larger proportions of subjects with gastric ulcer (97.8%) inhabited strains with complete cag-PAI, followed by gastric cancer (85.7%), non-ulcer dyspepsia (7.1%), and duodenal ulcer (6.9%), significant differences were found in the percentage distribution of the genes in all the clinical groups studied. It was found that strains with complete cag-PAI were able to cause severe histological damage than with the partially deleted ones. CONCLUSION: The cag-PAI is a strong virulent marker in the disease pathogenesis as it is shown that a large number of those infected with strain with complete cag-PAI had one or the other of the irreversible gastric pathologies and interestingly 18.5% of them developed gastric carcinoma. The presence of an intact cag-PAI correlates with the development of more severe pathology, and such strains were found more frequently in patients with severe gastroduodenal disease. Partial deletions of the cag-PAI appear to be sufficient to render the organism less pathogenic.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Dispepsia , Ilhas Genômicas , Helicobacter pylori/genética , Úlcera Péptica , Neoplasias Gástricas , Adulto , Idoso , Dispepsia/microbiologia , Dispepsia/patologia , Feminino , Infecções por Helicobacter/patologia , Helicobacter pylori/patogenicidade , Humanos , Masculino , Pessoa de Meia-Idade , Úlcera Péptica/microbiologia , Úlcera Péptica/patologia , Regiões Promotoras Genéticas , Estatística como Assunto , Neoplasias Gástricas/microbiologia , Neoplasias Gástricas/patologia
20.
J Adv Res ; 5(3): 277-94, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25685495

RESUMO

Since last few years, an impressive amount of data has been generated regarding the basic in vitro and in vivo biology of neural stem cells (NSCs) and there is much far hope for the success in cell replacement therapies for several human neurodegenerative diseases and stroke. The discovery of adult neurogenesis (the endogenous production of new neurons) in the mammalian brain more than 40 years ago has resulted in a wealth of knowledge about stem cells biology in neuroscience research. Various studies have done in search of a suitable source for NSCs which could be used in animal models to understand the basic and transplantation biology before treating to human. The difficulties in isolating pure population of NSCs limit the study of neural stem behavior and factors that regulate them. Several studies on human fetal brain and spinal cord derived NSCs in animal models have shown some interesting results for cell replacement therapies in many neurodegenerative diseases and stroke models. Also the methods and conditions used for in vitro culture of these cells provide an important base for their applicability and specificity in a definite target of the disease. Various important developments and modifications have been made in stem cells research which is needed to be more specified and enrolment in clinical studies using advanced approaches. This review explains about the current perspectives and suitable sources for NSCs isolation, characterization, in vitro proliferation and their use in cell replacement therapies for the treatment of various neurodegenerative diseases and strokes.

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