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1.
Int J Biol Macromol ; 265(Pt 2): 130991, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38521336

RESUMO

The most prevalent carbohydrate on Earth is cellulose, a polysaccharide composed of glucose units that may be found in diverse sources, such as cell walls of wood and plants and some bacterial and algal species. The inherent availability of this versatile material provides a natural pathway for exploring and identifying novel uses. This study comprehensively analyzes cellulose and its derivatives, exploring their structural and biochemical features and assessing their wide-ranging applications in tissue fabrication, surgical dressings, and pharmaceutical delivery systems. The use of diverse cellulose particles as fundamental components gives rise to materials with distinct microstructures and characteristics, fulfilling the requirements of various biological applications. Although cellulose boasts substantial potential across various sectors, its exploration has predominantly unfolded within industrial realms, leaving the biomedical domain somewhat overlooked in its initial stages. This investigation, therefore, endeavors to shed light on the contemporary strides made in synthesizing cellulose and its derivatives. These innovative techniques give rise to distinctive attributes, presenting a treasure trove of advantages for their compelling integration into the intricate tapestry of biomedical applications.


Assuntos
Celulose , Hidrogéis , Celulose/química , Hidrogéis/química , Polissacarídeos/química , Madeira , Engenharia Tecidual/métodos
4.
J Pharm Bioallied Sci ; 15(Suppl 2): S1257-S1261, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37694002

RESUMO

Aims and Objectives: To determine the choroidal thickness (mainly subfoveal) using spectral domain optical coherence tomography (SD-OCT) in amblyopic eyes and to compare it with the choroidal thickness (CT) of healthy fellow eyes. Materials and Methods: In this prospective study, 140 eyes of 70 patients (aged 5-40 years) with strabismic and anisometropic amblyopia were examined using enhanced depth imaging (EDI) mode in SD-OCT. The CT was measured directly below the fovea and six other locations: 500 µ, 1000 µ, and 1500 µ from fovea in both nasal and temporal quadrants. Results: The mean age of the patients was 22.5 ± 11.2 years. The mean Best Corrected Visual Acuity (BCVA) in the amblyopic eyes was 0.87 ± 0.47 logMAR and 0 ± 0.02 logMAR in control eyes. The average subfoveal CT was 341.73 ± 60.39 µm in the amblyopic eyes and 314.77 ± 48.12 µm in the fellow eyes. Subgroup analysis showed that the patients with anisometropic amblyopia had a significantly thicker choroid as compared to the fellow healthy eyes (P = 0.00), whereas in strabismic amblyopic eyes, this difference was not significantly significant (P = 0.064). Conclusion: Significant choroidal thickening was observed in subjects with amblyopia, which may contribute to the amblyopia pathogenesis and this could be used as a diagnostic parameter for amblyopia. These changes were more pronounced in patients with anisometropic amblyopia than strabismic amblyopia.

6.
Ophthalmol Retina ; 7(6): e7, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37270264
8.
Environ Res ; 231(Pt 1): 116103, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37178745

RESUMO

Copper and dysprosium doped NiFe2O4 magnetic nanomaterials, Ni1-xCuxDyyFe2-yO4 (x = y = 0.00, 0.01, 0.02, 0.03), was prepared by utilizing sol-gel auto-combustion approach to inspect the photodegradation of methylene blue (MB) pollutant and also, to perform the electrocatalytic water splitting and antibacterial studies. The XRD analysis reveal the growth of a single-phase spinel cubic structure for produced nanomaterials. The magnetic traits show an increasing trend in saturation magnetization (Ms) from 40.71 to 47.90 emu/g along with a decreasing behaviour of coercivity from 158.09 to 156.34 Oe at lower and higher Cu and Dy doping content (x = 0.0-0.01). The study of optical band gap values of copper and dysprosium-doped nickel nanomaterials decreased from 1.71 to 1.52 eV. This will increase the photocatalytic degradation of methylene blue pollutant from 88.57% to 93.67% under natural sunlight, respectively. These findings clearly show that under natural sunlight irradiation for 60 min, the produced N4 photocatalyst displays the greatest photocatalytic activity with a maximum removal percentage of 93.67%. The electrocatalytic characteristics of produced magnetic nanomaterials for both HER and OER were examined with a Calomel electrode taking as a reference in a 0.5 N H2SO4 and 0.1 N KOH electrolyte. The N4 electrode demonstrated considerable 10 and 0.024 mA/cm2 of current density, with onset potentials of 0.99 and 1.5 V for HER and OER and also, have tafel slopes of 58.04 and 295 mV/dec, respectively. The antibacterial activity for produced magnetic nanomaterials was examined against various bacteria (Bacillus subtilis, Staphylococcus aureus, S. typhi, and P. aeruginosa) in which N3 sample produced significant inhibition zone against gram-positive bacteria (Bacillus subtilis and Staphylococcus aureus) but no zone of inhibition against gram-negative bacteria (S. typhi and P. aeruginosa). With all these superior traits, the produced magnetic nanomaterials are highly valuable for the wastewater remediation, hydrogen evolution, and biological applications.


Assuntos
Cobre , Nanopartículas de Magnetita , Azul de Metileno/química , Disprósio , Antibacterianos/farmacologia , Antibacterianos/química
9.
Ophthalmol Retina ; 7(3): 275-281, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36195261

RESUMO

OBJECTIVE: To analyze the outcomes of salvage intra-arterial chemotherapy (IAC) for recurrent or persistent intraocular retinoblastoma after failure with other treatment modalities. DESIGN: Retrospective study. SUBJECTS: Twenty-four eyes of 23 patients. INTERVENTION: Intra-arterial chemotherapy. MAIN OUTCOME MEASURES: Globe salvage, metastasis, and death. RESULTS: The mean age at the time of salvage IAC was 41 months (median, 36 months; range, 14-86 months). All patients (n = 23) received IV chemotherapy (IVC) as the primary treatment. The mean number of IVC cycles before salvage IAC was 10 (median, 12; range, 6-18). The indications for salvage IAC were tumor recurrence (n = 17; 71%) or persistent tumor (n = 7; 29%) post-IVC. The mean number of salvage IAC cycles was 3 (median, 3; range, 1-6). Of 24 eyes, 17 eyes (71%) achieved tumor regression with salvage IAC, whereas 7 (29%) eyes displayed poor response. Of these 17 eyes with initial tumor regression, 9 (38%) eyes sustained good response, whereas 8 (33%) eyes displayed tumor recurrence over a mean follow-up period of 21 months (median, 21 months; range, 6-44 months). The mean interval between IAC and tumor recurrence (n = 8) was 4 months (median, 3 months; range, 1-14 months). Of these 8 eyes, globe salvage was achieved in 5 (21%) eyes with additional alternate treatment. Of the 7 eyes with poor response to IAC, globe salvage was achieved in 1 (4%) eye with additional alternate treatment. Overall, globe salvage was achieved in 15 (63%) eyes. CONCLUSIONS: Salvage IAC is an effective treatment for recurrent and persistent retinoblastoma, enabling globe salvage in 63% cases. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.


Assuntos
Neoplasias da Retina , Retinoblastoma , Humanos , Pré-Escolar , Retinoblastoma/tratamento farmacológico , Neoplasias da Retina/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Estudos Retrospectivos , Melfalan , Infusões Intra-Arteriais
11.
Beilstein J Nanotechnol ; 13: 1316-1336, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36447562

RESUMO

One of the most enticing approaches to environmental restoration and energy conversion is photocatalysis powered by solar light. Traditional photocatalysts have limited practical uses due to inadequate light absorption, charge separation, and unknown reaction mechanisms. Discovering new visible-light photocatalysts and investigating their modification is crucial in photocatalysis. Bi-based photocatalytic nanomaterials have gotten much interest as they exhibit distinctive geometric shapes, flexible electronic structures, and good photocatalytic performance under visible light. They can be employed as stand-alone photocatalysts for pollution control and energy production, but they do not have optimum efficacy. As a result, their photocatalytic effectiveness has been significantly improved in the recent decades. Numerous newly created concepts and methodologies have brought significant progress in defining the fundamental features of photocatalysts, upgrading the photocatalytic ability, and understanding essential reactions of the photocatalytic process. This paper provides insights into the characteristics of Bi-based photocatalysts, making them a promising future nanomaterial for environmental remediation. The current review discusses the fabrication techniques and enhancement in Bi-based semiconductor photocatalysts. Various environmental applications, such as H2 generation and elimination of water pollutants, are also discussed in terms of semiconductor photocatalysis. Future developments will be guided by the uses, issues, and possibilities of Bi-based photocatalysts.

12.
Indian J Ophthalmol ; 70(11): 3865-3868, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36308115

RESUMO

Purpose: : The study was conducted to calculate and compare the surgically induced astigmatism (SIA) in chevron, frown, and straight incisions in manual small-incision cataract surgery (MSICS). Methods: A prospective, hospital-based study was conducted on 90 patients aged 50 years and above with nuclear sclerosis of grade 4 or more. Each group had 30 patients, divided into Group V (chevron incision), Group S (straight incision), and Group F (frown incision). Patients who had with-the-rule (WTR) astigmatism were operated on through a chevron or straight incision superiorly, while patients who had against-the-rule (ATR) astigmatism underwent MSICS through a temporal frown incision. The patients were followed up post-operatively on days 1, 7, 6 weeks, and 12 weeks, and at each visit, the uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), and SIA were calculated and compared. Results: The mean age of all the patients was 66.22 ± 8.05 years. BCVA of at least 6/18 or better at 12 weeks post-operatively was achieved in 29 patients (97%) in Group V, 28 patients (93%) in Group F, and 29 patients (97%) in Group S. The mean SIA in Group V was 0.34D ± 0.22D, in Group S was 0.97D ± 0.29D, and in Group F was 0.575D ± 0.25D. Conclusion: SIA by chevron incision is the least followed by the frown incision and straight incision. The superiorly placed chevron incision in WTR astigmatism provided optimal results for the best UCVA and minimal SIA. The temporal frown incision in ATR astigmatism also had good results.


Assuntos
Astigmatismo , Extração de Catarata , Catarata , Facoemulsificação , Ferida Cirúrgica , Humanos , Pessoa de Meia-Idade , Idoso , Astigmatismo/diagnóstico , Astigmatismo/etiologia , Astigmatismo/cirurgia , Estudos Prospectivos , Córnea/cirurgia , Extração de Catarata/efeitos adversos , Extração de Catarata/métodos , Catarata/diagnóstico , Ferida Cirúrgica/cirurgia , Facoemulsificação/métodos
13.
Chemosphere ; 294: 133706, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35066082

RESUMO

This study aims at manufacturing Ce3+/Ni2+ ions doped Mg nanoferrites by the sol-gel method for the photocatalytic degradation of rhodamine B and crystal violet pollutants under visible natural sunlight. The particle size of synthesized nanoferrites was calculated through XRD, Hall-William plots, and TEM analysis, which perfectly agree with each other. FTIR study investigated the existence of stretching vibrations in M - O (metal-oxygen) complexes at the tetrahedral (A-site) and octahedral sites (B-site). The Raman spectra of synthesized nanophotocatalysts show the presence of four vibrational modes (Eg + 2T2g + A1g), providing suitable information of occupancy of Mg2+, Ce3+, Ni2+, and Fe3+ ions at the interstitial sites of undoped and Ce3+/Ni2+ doped MgFe2O4 crystal structure. The synthesized MGF3 nanophotocatalyst performs well with degradation of 97.674% crystal violet (CV) and 90.05% rhodamine B (RhB) under natural sunlight in 60 min. The experimental results showed that doped MgFe2O4 nanoferrites have a high tendency to photodegrade the RhB and CV dyes in an aqueous form. The pseudo-first-order equation reflects the best photocatalytic process kinetics and studied the feasibility of RhB and CV dyes adsorption on the doped and undoped MgFe2O4 nanoferrites. The results show good support for adsorption by the spontaneous photodegradation process. The excellent photocatalytic activity of synthesized nanoferrites under natural sunlight verifies them as a potential candidate for the photodegradation of organic dyes. Finally, the antibacterial activity of magnetic nanoferrites was examined against S. aureus and E. Coli. The studies demonstrated that synthesized magnetic nanoferrites were more effective against S. aureus.


Assuntos
Poluentes Ambientais , Violeta Genciana , Catálise , Escherichia coli , Fotólise , Rodaminas , Staphylococcus aureus , Luz Solar
14.
Sci Rep ; 10(1): 7881, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398650

RESUMO

A facile green route has been employed for the synthesis of ZnO and Ag-doped ZnO using Cannabis sativa as a reducing and stabilizing agent. The as-synthesized nanoparticles were characterized and tested for photocatalytic dye degradation and antimicrobial activity. The results suggested that nanoparticles have shown antimicrobial activity against different human pathogenic bacteria (Escherichia coli, Klebsiella pneumonia, MRSA, Pseudomonas aeruginosa, Salmonella typhi, Staphylococcus aureus) and fungal strains (Fusarium spp. and Rosellinia necatrix). Ag-doped nanoparticles comparatively have shown better removal Congo red and methyl orange under visible light. Therefore, green synthesized nanoparticles could have beneficial applications in environmental science and biological field.


Assuntos
Antibacterianos/toxicidade , Compostos Azo/metabolismo , Nanopartículas Metálicas/toxicidade , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/química , Compostos Azo/química , Cannabis/química , Catálise/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Fusarium/efeitos dos fármacos , Química Verde/métodos , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana/métodos , Microscopia Eletrônica , Estrutura Molecular , Oxirredução , Folhas de Planta/química , Pseudomonas aeruginosa/efeitos dos fármacos , Espectrometria por Raios X , Staphylococcus aureus/efeitos dos fármacos , Difração de Raios X
15.
Glob Heart ; 13(4): 267-274.e2, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30197242

RESUMO

BACKGROUND: Despite the high prevalence of rheumatic heart disease (RHD) in developing countries such as India, data on characteristics, complications, and treatment practices are lacking. The HP-RHD (Himachal Pradesh Rheumatic Heart Disease) registry aimed at reporting these parameters in patients with RHD from a northern state of India. METHODS: A total of 2,005 consecutive patients of RHD were enrolled over a period of 6 years (2011 to 2016) in the present study. The clinical characteristics, complications, and treatment practices were systematically recorded. RESULTS: The mean age for patients with RHD was 40.3 ± 14.3 (range 5 to 83 years). RHD predominantly affected females (72.3%) and population from rural background (92%). Multivalvular involvement was frequent (43.2%), mitral valve was the commonest affected valve (83.3%). The majority of the patients had moderate-to-severe valvular dysfunction (69.3%). Mitral and tricuspid valve involvement was more frequent in female subjects compared with more frequent aortic valve involvement in male subjects (p < 0.001). The major adverse cardiovascular events were recorded in 23.4% patients at the time of registry and comprised mainly advanced heart failure (15.6%), peripheral embolism (4.1%), and stroke (3.9%). The independent risk determinants of major adverse cardiovascular events (were advanced age (odds ratio [OR]: 1.01; 95% confidence interval [CI]: 1.00-1.02), severe mitral stenosis (OR: 1.73; 95% CI: 1.34-2.20), severe tricuspid regurgitation (OR: 2.11; 95% CI: 1.48-3.02), presence of pulmonary artery hypertension (OR: 1.33; 95% CI: 1.04-1.69), and atrial fibrillation (OR: 1.64; 95% CI: 1.28-2.11). Evidence-based use of oral anticoagulant therapy was documented in 77.7% of high-risk patients. Only 28.5% of study population was receiving secondary prophylaxis. CONCLUSIONS: Complications in patients with RHD increase with age and worsening valvular dysfunction. Programs focused on early detection and evidence-based management will assist in improving outcomes.


Assuntos
Antirreumáticos/uso terapêutico , Doenças das Valvas Cardíacas/prevenção & controle , Sistema de Registros , Cardiopatia Reumática/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Seguimentos , Doenças das Valvas Cardíacas/epidemiologia , Doenças das Valvas Cardíacas/etiologia , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Prevalência , Prognóstico , Estudos Prospectivos , Cardiopatia Reumática/complicações , Cardiopatia Reumática/terapia , Fatores de Tempo , Adulto Jovem
16.
J Pharm Pharmacol ; 69(2): 143-150, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28033667

RESUMO

OBJECTIVES: Present modalities for the diagnosis and treatment of diabetes still suffer from certain limitations such as erratic absorption, need of high dose, poor sensitivity or specificity, resistance, substantial morbidity and mortality, long-term complications, and patient-to-patient variability with lifetime treatment. METHODS: This study focused on the development of a water-in-oil-in-water metformin nanoemulsion as an effective method in diabetes treatment. As a Biopharmaceutics Classification System (BCS) class III drug, metformin is hydrophilic in nature with high solubility and poor absorption characteristics. To simultaneously facilitate gastrointestinal absorption and intestinal permeability, metformin was loaded into alginate nanocapsules prepared by an emulsion cross-linking technology. KEY FINDINGS: These prepared metformin-loaded alginate nanoparticles (MLANs) were characterized using transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, and photon correlation spectroscopy (PCS)-based particle size analysis. CONCLUSIONS: The drug loading and encapsulation efficiency in MLANs were 3.12 mg (the amount of metformin added in 100 mg of nanoparticles) and 78%, respectively. The results of in-vitro drug release studies and in-vivo efficacy tests (using animal models) demonstrated enhanced efficiency and response of MLANs relative to pure metformin. The efficacy of MLANs (46.8 mg/kg) was overall about three times higher than that of pure metformin150 mg/kg.


Assuntos
Alginatos/química , Liberação Controlada de Fármacos , Metformina/farmacocinética , Metformina/uso terapêutico , Nanopartículas/química , Animais , Glicemia/efeitos dos fármacos , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/uso terapêutico , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/química , Emulsões/química , Feminino , Teste de Tolerância a Glucose , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Hipoglicemiantes/química , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/uso terapêutico , Masculino , Metformina/química , Nanocápsulas/química , Nanocápsulas/ultraestrutura , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ratos
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