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1.
Small ; 19(50): e2304143, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37612811

RESUMO

The rational design of noble metal-free electrocatalysts holds great promise for cost-effective green hydrogen generation through water electrolysis. In this context, here, the development of a superhydrophilic bifunctional electrocatalyst that facilitates both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline conditions is demonstrated. This is achieved through the in situ growth of hierarchical NiMoO4 @CoMoO4 ·xH2 O nanostructure on nickel foam (NF) via a two-step hydrothermal synthesis method. NiMoO4 @CoMoO4 ·xH2 O/NF facilitates OER and HER at the overpotentials of 180 and 220 mV, respectively, at the current density of 10 mA cm-2 . The NiMoO4 @CoMoO4 ·xH2 O/NF ǁ NiMoO4 @CoMoO4 ·xH2 O/NF cell can be operated at a potential of 1.60 V compared to 1.63 V displayed by the system based on the Pt/C@NFǁRuO2 @NF standard electrode pair configuration at 10 mA cm-2 for overall water splitting. The density functional theory calculations for the OER process elucidate that the lowest ΔG of NiMoO4 @CoMoO4 compared to both Ni and NiMoO4 is due to the presence of Co in the OER catalytic site and its synergistic interaction with NiMoO4 . The preparative strategy and mechanistic understanding make the windows open for the large-scale production of the robust and less expensive electrode material for the overall water electrolysis.

2.
Chemistry ; 26(35): 7900-7911, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32363666

RESUMO

Hydrogen production is vital for meeting future energy demands and managing environmental sustainability. Electrolysis of water is considered as the suitable method for H2 generation in a carbon-free pathway. Herein, the synthesis of highly efficient Co9 S8 -Ni3 S2 based hierarchical nanoflower arrays on nickel foam (NF) is explored through the one-pot hydrothermal method (Co9 S8 -Ni3 S2 /NF) for overall water splitting applications. The nanoflower arrays are self-supported on the NF without any binder, possessing the required porosity and structural characteristics. The obtained Co9 S8 -Ni3 S2 /NF displays high hydrogen evolution reaction (HER), as well as oxygen evolution reaction (OER), activities in 1 m KOH solution. The overpotentials exhibited by this system at 25 mA cm-2 are nearly 277 and 102 mV for HER and OER, respectively, in 1 m KOH solution. Subsequently, the overall water splitting was performed in 1 m KOH solution by employing Co9 S8 -Ni3 S2 /NF as both the anode and cathode, where the system required only 1.49, 1.60, and 1.69 V to deliver the current densities of 10, 25, and 50 mA cm-2 , respectively. Comparison of the activity of Co9 S8 -Ni3 S2 /NF with the state-of-the-art Pt/C and RuO2 coated on NF displays an enhanced performance for Co9 S8 -Ni3 S2 /NF both in the half-cell as well as in the full cell, emphasizing the significance of the present work. The post analysis of the material after water electrolysis confirms that the surface Co(OH)2 formed during the course of the reaction serves as the favorable active sites. Overall, the activity modulation achieved in the present case is attributed to the presence of the open-pore morphology of the as formed nanoflowers of Co9 S8 -Ni3 S2 on NF and the simultaneous presence of the surface Co(OH)2 along with the highly conducting Co9 S8 -Ni3 S2 core, which facilitates the adsorption of the reactants and subsequently its conversion into the gaseous products during water electrolysis.

3.
Indian J Urol ; 36(1): 67-68, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31983832

RESUMO

Gas-containing renal stones is a rarely described complication of emphysematous pyelonephritis. Most of these patients are diabetic and almost all have urinary obstruction and stasis. Management of these patients may be associated with several complications.

4.
AAPS PharmSciTech ; 20(5): 180, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044335

RESUMO

The process of liposome fusion with cellular membrane plays key role in delivering encapsulated drug molecule into the cell. This process becomes very important for molecules having low permeability as they fail to reach the site of action located inside the cell. Ciprofloxacin (CIP), a broad-spectrum BCS class IV antibiotic, has poor permeability. In the present work, CIP-loaded liposomes were prepared using solvent evaporation method and optimized by 32 factorial design approach. The optimized batch of CIP-loaded liposomes was characterized for size, entrapment efficiency, zeta potential, FTIR, and microbial susceptibility study on Staphylococcus aureus (gram-positive bacteria) and Escherichia coli (gram-negative bacteria). Confocal microscopy was used to study the fusogenicity process of CIP-loaded liposomes with bacterial cells. Additionally, the kinetics of fusogenicity process was studied using SAXS for the first time. Surprisingly, the rate of fusion of CIP-loaded liposomes with cell wall of S. aureus was twice when compared to the cell wall of E. coli. It is believed that the current work can act as a roadmap in selection of proper excipients while developing formulations which would expedite the fusogenicity and may execute pharmacological activity of poorly penetrable drug molecules at lower dose.


Assuntos
Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ciprofloxacina/administração & dosagem , Ciprofloxacina/farmacologia , Permeabilidade da Membrana Celular/efeitos dos fármacos , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Escherichia coli/efeitos dos fármacos , Lipossomos , Staphylococcus aureus/efeitos dos fármacos
5.
Indian J Urol ; 33(4): 310-314, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29021656

RESUMO

INTRODUCTION: Percutaneous nephrolithotomy (PCNL) is an effective treatment for renal stones. Due to the significant pain and morbidity after standard PCNL because of nephrostomy tubes, various modifications of PCNL are being performed. We report a randomized trial comparing these modalities. MATERIALS AND METHODS: A total of 75 patients were randomized into three groups of 25 each: standard PCNL with nephrostomy tubes (Group 1), tubeless PCNL with ureteric stent and no nephrostomy (Group 2), and totally tubeless PCNL without ureteric catheter or nephrostomy (Group 3). Randomization was done at the end of the procedure for those patients satisfying the inclusion criteria based on duration of surgery, single puncture tract, intraoperative bleeding, stone burden, intact pelvicalyceal system, and no residual stones at the end of procedure. The outcomes measured were hemoglobin (Hb) drop, hemorrhage, need for blood transfusion, pyrexia, urine leak, pain score, analgesic requirement, and duration of hospital stay. RESULTS: There was no significant difference in hemorrhage, Hb drop, need for blood transfusion, and postoperative pyrexia among the groups. All patients except one in the standard group only had variable amount of urinary leak. The analgesic requirement and duration of hospital stay attained statistical significance in favor of tubeless and totally tubeless groups compared to the standard. CONCLUSIONS: Tubeless and totally tubeless PCNL are safe and effective method of renal stone management. Totally tubeless PCNL significantly reduced postoperative pain and morbidity compared to the tubeless method.

6.
Indian J Urol ; 32(4): 326-328, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27843221

RESUMO

ImmunoglobulinG4 related disease (IgG4RD) is a systemic fibroinflammatory disease recognized recently. This usually presents with multiorgan involvement. We are reporting a case of a35-year-old male patient with isolated IgG4RD of the testis. This patient presented with right testis pain which responded to conservative treatment. However, later, he reported with hard swelling in the right testis which on imaging was suggestive of malignancy and hence underwent radical orchiectomy. Histopathology with immunohistochemical staining confirmed IgG4RD of the testis. To the best of our knowledge, this is the first report of purely isolated case of IgG4RD of testis in English literature.

7.
J Mater Sci Mater Med ; 26(8): 216, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26216552

RESUMO

The paper presents the experimental studies pertaining to the adsorption of bovine serum albumin (BSA) on the nanoparticles of nickel ferrite (NiFe2O4) with a view of correlating the adsorption properties to their microstructure and zeta potentials. Physical properties of two kinds of nickel ferrites, one synthesized by thermal plasma route and the other by chemical co-precipitation method, are compared. Maximum adsorption (231.57 µg/mg) of BSA onto nickel ferrite nanoparticles, at body temperature (37 °C) was observed at pH-value of 5.58 for the thermal plasma synthesized particles showing its higher adsorption capacity than those synthesized by wet chemical means (178.71 µg/mg). Under the same physical conditions the value of zeta potential, obtained for the former, was higher than that of the latter over a wide range of pH values (3.64-9.66). This is attributed to the differences in the specific surface energies of the two kinds of nanoparticles arising from the degree of crystallinity. The paper presents the experimental evidence for the single crystalline nature of the individual nanoparticles, with mean size of 32 nm, for the thermal plasma synthesized particles as evidenced from the high resolution transmission electron microscopy and electron diffraction analysis. The measurements also reveal the poor crystalline morphology in the chemically prepared particles (mean size of 28 nm) although the X-ray diffraction patterns are not much different. The atomic force microscopy images confirm that the surfaces of plasma synthesized nanoparticles possesses higher surface roughness than that of chemically synthesized one. Presence of adsorbed protein was confirmed by vibrational spectroscopy. The Langmuir adsorption model is found to fit into the experimental data better than the Freundlich adsorption model.


Assuntos
Compostos Férricos/química , Nanopartículas de Magnetita/química , Níquel/química , Soroalbumina Bovina/química , Adsorção , Animais , Materiais Biocompatíveis/química , Bovinos , Magnetismo , Nanopartículas de Magnetita/ultraestrutura , Teste de Materiais , Microscopia de Força Atômica , Microscopia Eletrônica de Transmissão , Nanotecnologia , Tamanho da Partícula , Gases em Plasma , Difração de Pó , Soroalbumina Bovina/isolamento & purificação , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
8.
AAPS PharmSciTech ; 16(5): 1153-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25716330

RESUMO

The present work explores inner structuration of in situ gelling system consisting of glyceryl monooleate (GMO) and oleic acid (OA). The system under study involves investigation of microstructural changes which are believed to govern the pharmaceutical performance of final formulation. The changes which are often termed mesophasic transformation were analysed by small angle X-ray scattering (SAXS), differential scanning calorimetry (DSC), rheology and plane polarised light (PPL) microscopy. The current work revealed transformation of blank system from W/O emulsion to reverse hexagonal structure upon addition of structural analogues of ibuprofen. Such transformations are believed to occur due to increased hydrophobic volume within system as probed by SAXS analysis. The findings of SAXS studies were well supported by DSC, rheology and PPL microscopy. The study established inverse relationship between log P value of structural analogues of ibuprofen and the degree of binding of water molecules to surfactant chains. Such relationship had pronounced effect on sol-gel transformation process. The prepared in situ gelling system showed sustained drug release which followed Higuchi model.


Assuntos
Anti-Inflamatórios não Esteroides/química , Portadores de Fármacos , Ibuprofeno/química , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada , Composição de Medicamentos , Emulsões , Géis , Interações Hidrofóbicas e Hidrofílicas , Cinética , Cristais Líquidos , Microscopia de Polarização , Modelos Químicos , Estrutura Molecular , Reologia , Espalhamento a Baixo Ângulo , Solubilidade , Relação Estrutura-Atividade , Tensoativos/química , Água/química , Difração de Raios X
9.
Indian J Urol ; 31(2): 142-3, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25878418

RESUMO

Exstrophy of the urinary bladder is a rare congential anomaly. The most common malignancy is an adenocarcinoma in these patients. Squamous cell carcinoma (SCC) occurring in these patients is uncommon and usually has a bad prognosis. The management of these patients is challenging and may require extensive reconstructive procedures. We report a case of SCC in a corrected bladder exstrophy patient who presented with an ulcerated mass in the lower abdomen extending to the base of the penis. Six months after extensive radical ablative surgery with reconstruction of the abdominal wall, the patient remained free of recurrence.

10.
Indian J Urol ; 31(3): 259-61, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26166975

RESUMO

Bacillus Calmette-Guerin (BCG) is considered the most effective adjunctive treatment available to treat superficial bladder carcinoma. Although BCG is well tolerated by most patients, it may be associated with adverse effects. One of these is BCG granulomas in the kidney. We herein report a case of a 52-year-old patient who, during a surveillance contrast-enhanced computed tomography (CT) scan, was found to have multiple hypodense lesions in the left kidney. Ultrasound-guided biopsy proved it to be BCG granulomas. After 3 months of anti-tubercular treatment, a repeat CT showed complete resolution of the lesions.

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