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1.
Braz. j. biol ; 84: e250916, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1345552

RESUMO

Abstract The study was conducted to evaluate the effect of Moringa olifera on the growth and gut health of Tilapia (Oreochromis niloticus). The feed having 30% crude protein was prepared as an experimental diet with 4%, 8% and 10% M. olifera leaf supplementation, respectively. The control diet was devoid of M. olifera leaves. The 10 weeks feeding trial was carried out on 60 fish in aquaria. Fish was fed @ 3% of body weight twice a day. Diet with the high level of inclusion of M. olifera leaves significantly increased the growth rate, Survival Rate (SR), Specific Growth Rate (SGR) and Feed Conversion Efficiency (FCE) in all treatment groups compared to the control group. Similarly, Feed Conversion Ratio (FCR) gradually decreased and found highly-significant. To check the gut health of the Tilapia, random samples were selected and dissected. Nutrient agar was used as culture media to check the growth of bacteria. Pour Plate Method was used for viable colonies count by colony counter. Through staining method, the different bacteria such as Escherichia coli, Salmonella, Shigella and Pseudomonas aeruginosa were identify abundantly in the intestine of control diet fish but less number present in treatment diets groups. These results showed that M. olifera leaves up to 10% of dietary protein can be used for Nile tilapia for significant growth and healthy gut microbiota of fish.


Resumo O estudo foi conduzido para avaliar o efeito da Moringa olifera no crescimento e saúde intestinal da tilápia (Oreochromis niloticus). A ração com 30% de proteína bruta foi preparada como dieta experimental com 4%, 8% e 10% de suplementação de folhas de M. olifera, respectivamente. A dieta controle foi desprovida de folhas de M. olifera. O ensaio de alimentação de 10 semanas foi realizado em 60 peixes em aquários. O peixe pesava 3% do peso corporal duas vezes ao dia. A dieta com alto nível de inclusão de folhas de M. olifera aumentou significativamente a taxa de crescimento, taxa de sobrevivência (SR), taxa de crescimento de sobrevivência (SGR) e eficiência de conversão alimentar (FCE) em todos os grupos de tratamento em comparação com o grupo de controle. Da mesma forma, a taxa de conversão de alimentação (FCR) diminuiu gradualmente e foi considerada altamente significativa. Para verificar a saúde intestinal da tilápia, amostras aleatórias foram selecionadas e dissecadas. O ágar nutriente foi usado como meio de cultura para verificar o crescimento das bactérias. O método da placa de Verter foi usado para a contagem de colônias viáveis ​​por contador de colônias. Através do método de coloração, diferentes como Escherichia coli, Salmonella, Shigella e Pseudomonas aeruginosa foram identificados abundantemente no intestino de peixes da dieta controle, mas em menor número nos grupos de dieta de tratamento. Esses resultados mostraram que M. olifera deixa até 10% da proteína dietética e pode ser usado para tilápia do Nilo para um crescimento significativo e microbiota intestinal saudável de peixes.


Assuntos
Animais , Ciclídeos , Moringa , Microbioma Gastrointestinal , Folhas de Planta , Suplementos Nutricionais/análise , Dieta/veterinária , Ração Animal/análise
2.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469242

RESUMO

Abstract The study was conducted to evaluate the effect of Moringa olifera on the growth and gut health of Tilapia (Oreochromis niloticus). The feed having 30% crude protein was prepared as an experimental diet with 4%, 8% and 10% M. olifera leaf supplementation, respectively. The control diet was devoid of M. olifera leaves. The 10 weeks feeding trial was carried out on 60 fish in aquaria. Fish was fed @ 3% of body weight twice a day. Diet with the high level of inclusion of M. olifera leaves significantly increased the growth rate, Survival Rate (SR), Specific Growth Rate (SGR) and Feed Conversion Efficiency (FCE) in all treatment groups compared to the control group. Similarly, Feed Conversion Ratio (FCR) gradually decreased and found highly-significant. To check the gut health of the Tilapia, random samples were selected and dissected. Nutrient agar was used as culture media to check the growth of bacteria. Pour Plate Method was used for viable colonies count by colony counter. Through staining method, the different bacteria such as Escherichia coli, Salmonella, Shigella and Pseudomonas aeruginosa were identify abundantly in the intestine of control diet fish but less number present in treatment diets groups. These results showed that M. olifera leaves up to 10% of dietary protein can be used for Nile tilapia for significant growth and healthy gut microbiota of fish.


Resumo O estudo foi conduzido para avaliar o efeito da Moringa olifera no crescimento e saúde intestinal da tilápia (Oreochromis niloticus). A ração com 30% de proteína bruta foi preparada como dieta experimental com 4%, 8% e 10% de suplementação de folhas de M. olifera, respectivamente. A dieta controle foi desprovida de folhas de M. olifera. O ensaio de alimentação de 10 semanas foi realizado em 60 peixes em aquários. O peixe pesava 3% do peso corporal duas vezes ao dia. A dieta com alto nível de inclusão de folhas de M. olifera aumentou significativamente a taxa de crescimento, taxa de sobrevivência (SR), taxa de crescimento de sobrevivência (SGR) e eficiência de conversão alimentar (FCE) em todos os grupos de tratamento em comparação com o grupo de controle. Da mesma forma, a taxa de conversão de alimentação (FCR) diminuiu gradualmente e foi considerada altamente significativa. Para verificar a saúde intestinal da tilápia, amostras aleatórias foram selecionadas e dissecadas. O ágar nutriente foi usado como meio de cultura para verificar o crescimento das bactérias. O método da placa de Verter foi usado para a contagem de colônias viáveis por contador de colônias. Através do método de coloração, diferentes como Escherichia coli, Salmonella, Shigella e Pseudomonas aeruginosa foram identificados abundantemente no intestino de peixes da dieta controle, mas em menor número nos grupos de dieta de tratamento. Esses resultados mostraram que M. olifera deixa até 10% da proteína dietética e pode ser usado para tilápia do Nilo para um crescimento significativo e microbiota intestinal saudável de peixes.

3.
AJNR Am J Neuroradiol ; 44(3): 274-282, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36822828

RESUMO

BACKGROUND AND PURPOSE: Resting-state fMRI helps identify neural networks in presurgical patients who may be limited in their ability to undergo task-fMRI. The purpose of this study was to determine the accuracy of identifying the language network from resting-state-fMRI independent component analysis (ICA) maps. MATERIALS AND METHODS: Through retrospective analysis, patients who underwent both resting-state-fMRI and task-fMRI were compared by identifying the language network from the resting-state-fMRI data by 3 reviewers. Blinded to task-fMRI maps, these investigators independently reviewed resting-state-fMRI ICA maps to potentially identify the language network. Reviewers ranked up to 3 top choices for the candidate resting-state-fMRI language map. We evaluated associations between the probability of correct identification of the language network and some potential factors. RESULTS: Patients included 29 men and 14 women with a mean age of 41 years. Reviewer 1 (with 17 years' experience) demonstrated the highest overall accuracy with 72%; reviewers 2 and 3 (with 2 and 7 years' experience, respectively) had a similar percentage of correct responses (50% and 55%). The highest accuracy used ICA50 and the top 3 choices (81%, 65%, and 60% for reviewers 1, 2, and 3, respectively). The lowest accuracy used ICA50, limiting each reviewer to the top choice (58%, 35%, and 42%). CONCLUSIONS: We demonstrate variability in the accuracy of blinded identification of resting-state-fMRI language networks across reviewers with different years of experience.


Assuntos
Mapeamento Encefálico , Neoplasias Encefálicas , Masculino , Humanos , Feminino , Adulto , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Idioma , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia
4.
AJNR Am J Neuroradiol ; 44(2): 125-133, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36702502

RESUMO

BACKGROUND AND PURPOSE: A scout accelerated motion estimation and reduction (SAMER) framework has been developed for efficient retrospective motion correction. The goal of this study was to perform an initial evaluation of SAMER in a series of clinical brain MR imaging examinations. MATERIALS AND METHODS: Ninety-seven patients who underwent MR imaging in the inpatient and emergency department settings were included in the study. SAMER motion correction was retrospectively applied to an accelerated T1-weighted MPRAGE sequence that was included in brain MR imaging examinations performed with and without contrast. Two blinded neuroradiologists graded images with and without SAMER motion correction on a 5-tier motion severity scale (none = 1, minimal = 2, mild = 3, moderate = 4, severe = 5). RESULTS: The median SAMER reconstruction time was 1 minute 47 seconds. SAMER motion correction significantly improved overall motion grades across all examinations (P < .005). Motion artifacts were reduced in 28% of cases, unchanged in 64% of cases, and increased in 8% of cases. SAMER improved motion grades in 100% of moderate motion cases and 75% of severe motion cases. Sixty-nine percent of nondiagnostic motion cases (grades 4 and 5) were considered diagnostic after SAMER motion correction. For cases with minimal or no motion, SAMER had negligible impact on the overall motion grade. For cases with mild, moderate, and severe motion, SAMER improved the motion grade by an average of 0.3 (SD, 0.5), 1.1 (SD, 0.3), and 1.1 (SD, 0.8) grades, respectively. CONCLUSIONS: SAMER improved the diagnostic image quality of clinical brain MR imaging examinations with motion artifacts. The improvement was most pronounced for cases with moderate or severe motion.


Assuntos
Pacientes Internados , Imageamento por Ressonância Magnética , Humanos , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Imageamento Tridimensional/métodos , Movimento (Física) , Artefatos , Processamento de Imagem Assistida por Computador/métodos
5.
Braz J Biol ; 84: e250916, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34705952

RESUMO

The study was conducted to evaluate the effect of Moringa olifera on the growth and gut health of Tilapia (Oreochromis niloticus). The feed having 30% crude protein was prepared as an experimental diet with 4%, 8% and 10% M. olifera leaf supplementation, respectively. The control diet was devoid of M. olifera leaves. The 10 weeks feeding trial was carried out on 60 fish in aquaria. Fish was fed @ 3% of body weight twice a day. Diet with the high level of inclusion of M. olifera leaves significantly increased the growth rate, Survival Rate (SR), Specific Growth Rate (SGR) and Feed Conversion Efficiency (FCE) in all treatment groups compared to the control group. Similarly, Feed Conversion Ratio (FCR) gradually decreased and found highly-significant. To check the gut health of the Tilapia, random samples were selected and dissected. Nutrient agar was used as culture media to check the growth of bacteria. Pour Plate Method was used for viable colonies count by colony counter. Through staining method, the different bacteria such as Escherichia coli, Salmonella, Shigella and Pseudomonas aeruginosa were identify abundantly in the intestine of control diet fish but less number present in treatment diets groups. These results showed that M. olifera leaves up to 10% of dietary protein can be used for Nile tilapia for significant growth and healthy gut microbiota of fish.


Assuntos
Ciclídeos , Microbioma Gastrointestinal , Moringa , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais/análise , Folhas de Planta
8.
Int J Biol Macromol ; 110: 540-549, 2018 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-29054521

RESUMO

Recent reports indicated DNA damaging potential of few-layer graphene in human cell systems. Here, we used computational technique to understand the interaction of both pristine (pG) or carboxyl functionalized graphene (fG) of different sizes (1, 6, and 10nm) with an important DNA repair protein p53. The molecular docking study revealed strong interaction between pG and DNA binding domains (DBD) of p53 with binding free energies (BE) varying from -12.0 (1nm) to -34 (6nm)kcal/mol, while fG showed relatively less interaction with BE varying from -6.7 (1nm) to -11.1 (6nm)kcal/mol. Most importantly, pG or fG bound p53-DBDs could not bind to DNA. Further, microarray analysis of human primary endothelial cells revealed graphene intervention on DNA damage and its structure-properties effect using comet assay studies. Thus, computational and experimental results revealed the structure-physicochemical property dependent adverse effects of graphene in DNA repair protein p53.


Assuntos
Simulação por Computador , Dano ao DNA , Fulerenos/química , Grafite/química , Simulação de Acoplamento Molecular , Proteína Supressora de Tumor p53/química , DNA/química , Humanos
9.
Int J Biol Macromol ; 74: 249-62, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25526695

RESUMO

The curcumin-encapsulated chitosan-graft-poly(N-vinyl caprolactam) nanoparticles containing gold nanoparticles (Au-CRC-TRC-NPs) were developed by ionic cross-linking method. After "optimum RF exposure" at 40 W for 5 min, Au-CRC-TRC-NPs dissipated heat energy in the range of ∼42°C, the lower critical solution temperature (LCST) of chitosan-graft-poly(N-vinyl caprolactam), causing controlled curcumin release and apoptosis to cancer cells. Further, in vivo PK/PD studies on swiss albino mice revealed that Au-CRC-TRC-NPs could be sustained in circulation for a week with no harm to internal organs. The colon tumor localization studies revealed that Au-CRC-TRC-NPs were retained in tumor for a week. These results throw light on their feasibility as multi-responsive nanomedicine for RF-assisted cancer treatment modalities.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Caprolactama/química , Quitosana/química , Curcumina/administração & dosagem , Curcumina/farmacologia , Nanopartículas/química , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos , Ouro/química , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Neoplasias/patologia , Neoplasias/terapia , Tamanho da Partícula , Tratamento por Radiofrequência Pulsada , Termodinâmica , Distribuição Tecidual , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/efeitos da radiação
10.
Nanotechnology ; 25(44): 445102, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25302535

RESUMO

The field of molecular detection and targeted imaging has evolved considerably with the introduction of fluorescent semiconductor nanocrystals. Manganese-doped zinc sulphide nanocrystals (ZnS:Mn NCs), which are widely used in electroluminescent displays, have been explored for the first time for direct immunofluorescent (IF) labeling of clinical tumor tissues. ZnS:Mn NCs developed through a facile wet chemistry route were capped using amino acid cysteine, conjugated to streptavidin and thereafter coupled to biotinylated epidermal growth factor receptor (EGFR) antibody utilizing the streptavidin-biotin linkage. The overall conjugation yielded stable EGFR antibody conjugated ZnS:Mn NCs (EGFR ZnS:Mn NCs) with a hydrodynamic diameter of 65 ± 15 nm, and having an intense orange-red fluorescence emission at 598 nm. Specific labeling of EGF receptors on EGFR(+ve) A431 cells in a co-culture with EGFR(-ve) NIH3T3 cells was demonstrated using these nanoprobes. The primary antibody conjugated fluorescent NCs could also clearly delineate EGFR over-expressing cells on clinical tumor tissues processed by formalin fixation as well as cryopreservation with a specificity of 86% and accuracy of 88%, in comparison to immunohistochemistry. Tumor tissues labeled with EGFR ZnS:Mn NCs showed good fluorescence emission when imaged after storage even at 15 months. Thus, ZnS nanobioconjugates with dopant-dependent and stable fluorescence emission show promise as an efficient, target-specific fluorophore that would enable long term IF labeling of any antigen of interest on clinical tissues.


Assuntos
Receptores ErbB/análise , Imunofluorescência/métodos , Glioma/metabolismo , Neoplasias Bucais/metabolismo , Nanopartículas/química , Neoplasias Cutâneas/metabolismo , Linhagem Celular Tumoral , Humanos , Manganês/química , Nanopartículas/ultraestrutura , Sulfetos/química , Compostos de Zinco/química
11.
Acta Biomater ; 10(5): 2112-24, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24389318

RESUMO

The present study reports an engineered poly-l-lactide-co-glycolic acid (PLGA)-casein polymer-protein hybrid nanocarrier 190±12nm in size entrapping a combination of chemically distinct (hydrophobic/hydrophilic) model drugs. A simple emulsion-precipitation route was adopted to prepare nearly monodispersed nanoparticles with distinct core/shell morphology entrapping paclitaxel (Ptx) in the core and epigallocatechin gallate (EGCG) in the shell, with the intention of providing a sequential and sustained release of these drugs. The idea was that an early release of EGCG would substantially increase the sensitivity of Ptx to cancer, thereby providing improved therapeutics at lower concentrations, with less toxicity. The hemo- and immunocompatibility of the core/shell nanomedicine was established in this study. The core/shell nanoparticles injected via the tail vein in Sprague-Dawley rats did not reveal any organ toxicity as was evident from histopathological evaluations of the major organs. In vivo pharmacokinetic studies in rats by high-performance liquid chromatography confirmed a sustained and sequential release of both the drugs in plasma, indicating prolonged circulation of the nanomedicine and enhanced availability of the drugs when compared to the bare drugs. Overall, the polymer-protein multilayered nanoparticles proved to be a promising platform for nanopolypharmaceutics.


Assuntos
Materiais Biocompatíveis/síntese química , Caseínas/química , Catequina/análogos & derivados , Ácido Láctico/química , Teste de Materiais , Nanomedicina/métodos , Paclitaxel/farmacocinética , Ácido Poliglicólico/química , Animais , Caseínas/toxicidade , Catequina/administração & dosagem , Catequina/sangue , Catequina/farmacocinética , Morte Celular/efeitos dos fármacos , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Citocinas/sangue , Humanos , Verde de Indocianina/metabolismo , Inflamação/patologia , Ácido Láctico/toxicidade , Camundongos , Nanopartículas/química , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Especificidade de Órgãos/efeitos dos fármacos , Paclitaxel/administração & dosagem , Paclitaxel/sangue , Tamanho da Partícula , Ácido Poliglicólico/toxicidade , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual/efeitos dos fármacos
12.
J Biomed Nanotechnol ; 8(6): 901-11, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23029998

RESUMO

Synthesis of biocompatible gold nanoparticles having tunable optical absorbance finds immense use in biomedical applications such as cancer diagnosis and photothermal therapy. Hence, it is imperative to develop environment and bio-friendly green chemical processes that aid in preparing gold nanoparticles with tunable optical properties. In the present work, phytochemicals present in the medicinal herb, viz., garlic, were used to provide the dual effects of reduction of gold salts to gold nanoparticles as well as stabilization, in a single step process. The optical tunability of nanogold with respect to concentration of precursor and volume of garlic extract, processing conditions of garlic, its differing molecular weight fractions, reaction time and temperature has been demonstrated. The presence of a range of anisotropic nanogold including nanotriangles, nanorods and nanospheres as evident from TEM endows the colloid with a tunable optical absorption, specifically into the near infrared region. In vitro stability studies of the colloidal suspension in various media including saline, BSA, histidine and PBS showed that gold nanoparticles did not aggregate with time or differing pH conditions. The role of the garlic phytochemicals in providing stability against agglomeration was also substantiated by FTIR studies. Cytotoxicity studies performed using spherical and anisotropic gold nanoparticles on MCF-7 and L929 cell lines proved the biocompatibility of the material up to high doses of 500 microg/ml. The present work highlights the role of garlic phytochemicals in preparing biocompatible metallic gold nanoparticles with tunable optical properties and good in vitro stability, suggesting its potential use for molecular imaging or therapeutic nanomedicines.


Assuntos
Materiais Biocompatíveis/química , Alho/metabolismo , Ouro/química , Química Verde , Nanopartículas Metálicas/química , Nanomedicina/métodos , Nanopartículas/química , Fitoterapia/métodos , Ressonância de Plasmônio de Superfície/métodos , Animais , Anisotropia , Linhagem Celular Tumoral , Humanos , Concentração de Íons de Hidrogênio , Camundongos , Microscopia Eletrônica de Transmissão/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Temperatura , Difração de Raios X
13.
Rev Port Pneumol ; 18(6): 299-303, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22622031

RESUMO

Amyloidosis results from proteins being deposited as insoluble ß-pleated sheets and disrupting organ function. Each precursor protein induces a separate spectrum of organ involvement, and different disease manifestations within the lung. Although autopsy findings often demonstrate amyloid deposits in various compartments of the lung, few are manifested pathologically. Amyloid lung nodules with positron emission tomography (PET) uptake are rare. We describe a rare case where PET uptake was detected in a pulmonary amyloid nodule. To our knowledge there are six previously reported cases in the English literature. This review also focuses on amyloid derived from immunoglobulin light-chain protein (AL disease), which most frequently involves the lung in both systemic and localized forms of the disease. Manifestations of AL-related lung disease range from nodules identified on incidental chest films to diffuse alveolar and septal deposition mimicking malignancy and or diffuse alveolar damage.


Assuntos
Amiloidose/diagnóstico por imagem , Pneumopatias/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Idoso , Diagnóstico Diferencial , Humanos , Masculino
14.
J Nanosci Nanotechnol ; 11(9): 7611-20, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22097465

RESUMO

The present study details the development of biotin tagged avidin functionalized Zinc Sulphide [ZnS] nanocrystals through a simple aqueous chemistry route at room temperature for targeted imaging applications. Surface functionalization of Manganese doped ZnS nanocrystals with L-cysteine provided functional groups that facilitated its conjugation to avidin. Further biotinylation of these particles through the strong non-covalent interaction between biotin and avidin enabled highly specific labeling of the biotin receptors on human hepatocellular carcinoma (HepG2) cells. The nanobioconjugates thus developed exhibited stable and brilliant fluorescence upon labeling the biotin receptors on cells as observed through fluorescence microscopy. Characterization studies using X-ray diffraction, dynamic light scattering as well as Fourier transform infrared spectroscopy revealed the bioconjugated particles to be appropriately functionalized and stable, with size ranging from 50 to 80 nm. Cytotoxicity of this material system evaluated using MTT, LDH leakage and apoptosis assay revealed its non-toxic nature even for high concentrations extending upto 250 microM and 48 hours of incubation. Our results confirmed that biotinylated ZnS nanocrystals offer great potential for highly specific labeling and targeted imaging of cancer cells.


Assuntos
Avidina/química , Materiais Biocompatíveis , Biotina/química , Carcinoma Hepatocelular/química , Corantes Fluorescentes/química , Neoplasias Hepáticas/química , Nanopartículas , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Citometria de Fluxo , Humanos , Neoplasias Hepáticas/patologia , Microscopia de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
J Biomater Sci Polym Ed ; 22(18): 2431-44, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21144167

RESUMO

Corticosteroids such as budesonide are the drugs of choice for the treatment of inflammatory disorders with an inherent limitation, viz., rapid elimination. To overcome this constraint and attain sustained release, budesonide was encapsulated in a biodegradable polymer, polycaprolactone (PCL), by DC electrospraying. By varying the experimental parameters involved in electrospraying such as applied voltage, flow rate, viscosity as well as conductivity of the polymer solution, the dimensionality of nanostructures was tuned from 1-D nanofibers to spherical nanoparticles. By adopting this rapid and viable method of DC electrospraying, we successfully prepared aqueous suspensions of nearly monodispersed, nano-sized drug encapsulated PCL. Drug encapsulation efficiency, in vitro drug release as well as biocompatibility studies of budesonide-loaded PCL nanobeads were carried out. The cytocompatible nanobeads prepared by electrospraying exhibited good encapsulation efficiency (approx. 75%), with controlled drug release enabled by the dissolution of the polymer. Our results demonstrate the potential of this novel technique of electrospraying in developing efficient drug encapsulated polymeric nanocarriers possessing sustained drug release profile.


Assuntos
Budesonida/administração & dosagem , Portadores de Fármacos , Glucocorticoides/administração & dosagem , Nanopartículas , Poliésteres , Budesonida/química , Budesonida/farmacocinética , Sobrevivência Celular , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/química , Portadores de Fármacos/síntese química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Condutividade Elétrica , Glucocorticoides/química , Glucocorticoides/farmacocinética , Humanos , Células MCF-7 , Teste de Materiais , Microscopia Eletrônica de Varredura , Nanofibras/química , Nanopartículas/química , Nanopartículas/ultraestrutura , Tamanho da Partícula , Poliésteres/química , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Suspensões , Viscosidade , Água/química
16.
J Mater Sci Mater Med ; 21(2): 807-13, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19802687

RESUMO

Antibiotic resistance of microorganisms is one of the major problems faced in the field of wound care and management resulting in complications like infection and delayed wound healing. Currently a lot of research is focused on developing newer antimicrobials to treat wounds infected with antibiotic resistant microorganisms. Silver has been used as an antimicrobial agent for a long time in the form of metallic silver and silver sulfadiazine ointments. Recently silver nanoparticles have come up as a potent antimicrobial agent and are finding diverse medical applications ranging from silver based dressings to silver coated medical devices. Chitin is a natural biopolymer with properties like biocompatibility and biodegradability. It is widely used as a scaffold for tissue engineering applications. In this work, we developed and characterized novel chitin/nanosilver composite scaffolds for wound healing applications. The antibacterial, blood clotting and cytotoxicity of the prepared composite scaffolds were also studied. These chitin/nanosilver composite scaffolds were found to be bactericidal against S. aureus and E. coli and good blood clotting ability. These results suggested that these chitin/nanosilver composite scaffolds could be used for wound healing applications.


Assuntos
Bactérias/efeitos dos fármacos , Bandagens , Quitina/química , Nanoestruturas/química , Prata/química , Prata/farmacologia , Tecidos Suporte , Antibacterianos/química , Antibacterianos/farmacologia , Desenho de Equipamento , Teste de Materiais , Nanoestruturas/administração & dosagem , Cicatrização/efeitos dos fármacos
17.
Nanotechnology ; 20(19): 195101, 2009 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-19420629

RESUMO

We report an interesting cell response to novel nanostructures formed on a titanium (Ti) surface by a simple non-lithographic bottom-up method. The surface topography of bio-implant materials dramatically influences their cell response. The aim of this study was to modify the surface of a titanium implant by a simple and cost effective processing technique and to determine its suitability for osteoblast attachment. A set of unique structures ranging from mesoporous nanoscaffolds, nanoflowers, nanoneedles, nanorods and octahedral bipyramids were fabricated by systematically tuning the hydrothermal conditions such as reaction medium composition, concentration, temperature and time duration. The cytotoxicity of surface modified Ti was assessed using human primary osteoblastic cells, and more than 90% of the cells were found to be viable after 24 h of incubation. Protein adsorption studies revealed that the surface modified nanostructures on titanium adsorbed more proteins, suggesting that they are capable of promoting cell adhesion/attachment. Immunofluorescence studies with vinculin antibody identified a distinctly different spread pattern of osteoblastic cells on hydrothermally modified nanostructured surfaces, indicating the formation of the focal adhesion points required for intracellular signaling. Thus, based on our results, we suggest that this study may present one of the best designs and systematic syntheses of biocompatible nanostructures on metallic Ti for orthopedic implant applications.


Assuntos
Materiais Biocompatíveis/química , Cristalização/métodos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Osteoblastos/citologia , Osteoblastos/fisiologia , Titânio/química , Sobrevivência Celular , Células Cultivadas , Humanos , Substâncias Macromoleculares/química , Teste de Materiais , Conformação Molecular , Nanotecnologia/métodos , Osteogênese/fisiologia , Tamanho da Partícula , Propriedades de Superfície
18.
J Mater Sci Mater Med ; 20 Suppl 1: S235-41, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18716714

RESUMO

The specific role of size scale, surface capping, and aspect ratio of zinc oxide (ZnO) particles on toxicity toward prokaryotic and eukaryotic cells was investigated. ZnO nano and microparticles of controlled size and morphology were synthesized by wet chemical methods. Cytotoxicity toward mammalian cells was studied using a human osteoblast cancer cell line and antibacterial activity using Gram-negative bacteria (Escherichia coli) as well as using Gram-positive bacteria (Staphylococcus aureus). Scanning electron microscopy (SEM) was conducted to characterize any visual features of the biocidal action of ZnO. We observed that antibacterial activity increased with reduction in particle size. Toxicity toward the human cancer cell line was considerably higher than previously observed by other researchers on the corresponding primary cells, suggesting selective toxicity of the ZnO to cancer cells. Surface capping was also found to profoundly influence the toxicity of ZnO nanoparticles toward the cancer cell line, with the toxicity of starch-capped ZnO being the lowest. Our results are found to be consistent with a membrane-related mechanism for nanoparticle toxicity toward microbes.


Assuntos
Bactérias/efeitos dos fármacos , Neoplasias Ósseas/patologia , Microesferas , Nanopartículas , Tamanho da Partícula , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Citotoxinas/química , Citotoxinas/farmacologia , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Nanopartículas/química , Nanopartículas/uso terapêutico , Osteoblastos/efeitos dos fármacos , Osteoblastos/patologia , Polietilenoglicóis/química , Staphylococcus aureus/efeitos dos fármacos , Células Tumorais Cultivadas
19.
J Nanosci Nanotechnol ; 7(2): 463-73, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17450780

RESUMO

A novel synthesis method is presented for the preparation of eco-friendly, doped semiconductor nanocrystals encapsulated within oxide-shells, both formed sequentially from a single-source solid-precursor. Highly luminescent ZnS nanoparticles, in situ doped with Cu(+)-Al3+ pairs and encapsulated with ZnO shells are prepared by the thermal decomposition of a solid-precursor compound, zinc sulfato-thiourea-oxyhydroxide, showing layered crystal structure. The precursor compound is prepared by an aqueous wet-chemical reaction involving necessary chemical reagents required for the precipitation, doping and inorganic surface capping of the nanoparticles. The elemental analysis (C, H, N, S, O, Zn), quantitative estimation of different chemical groups (SO4(2-) and NH4(-)) and infrared studies suggested that the precursor compound is formed by the intercalation of thiourea, and/or its derivatives thiocarbamate (CSNH2(-)), dithiocarbamate (CS2NH2(-)), etc., and ammonia into the gallery space of zinc-sulfato-oxyhydroxide corbel where the Zn(II) ions are both in the octahedral as well as tetrahedral coordination in the ratio 3 : 2 and the dopant ions are incorporated within octahedral voids. The powder X-ray diffraction of precursor compound shows high intensity basal reflection corresponding to the large lattice-plane spacing of d = 11.23 angstroms and the Rietveld analysis suggested orthorhombic structure with a = 9.71 angstroms, b = 12.48 angstroms, c = 26.43 angstroms, and beta = 90 degrees. Transmission electron microscopy studies show the presence of micrometer sized acicular monocrystallites with prismatic platy morphology. Controlled thermolysis of the solid-precursor at 70-110 degrees C leads to the collapse of layered structure due to the hydrolysis of interlayer thiourea molecules or its derivatives and the S2- ions liberated thereby reacts with the tetrahedral Zn(II) atoms leading to the precipitation of ZnS nanoparticles at the gallery space. During this process, the dopant ions situated at octahedral voids gets incorporated into the nano-ZnS lattice and results in bright photoluminescence. On further heat treatment above 1100 degrees C, the corbel zinc-oxyhydroxide sheets undergo dehydroxylation to form ZnO which eventually encapsulates the ZnS nanoparticles at the gallery leading to significant enhancement in the luminescence quantum efficiency, up to approximately 22%. The emission color of thus formed nano-ZnS/micro-ZnO composites could be tuned over wide spectral ranges from 480 to 618 nm and the spectral changes are attributed to a number of factors including lattice defects, Cu(+)-Al3+ dopant-pairs and iso-electronic oxygen in nano-ZnS and oxygen-vacancy or -interstitial centers in non-stoichiometric ZnO.


Assuntos
Luminescência , Substâncias Luminescentes/química , Nanopartículas/química , Nanotecnologia/métodos , Alumínio/química , Amônia/química , Cor , Cobre/química , Cristalização , Temperatura Alta , Luz , Substâncias Luminescentes/análise , Substâncias Luminescentes/efeitos da radiação , Teste de Materiais , Microscopia Eletrônica de Transmissão , Modelos Químicos , Nanopartículas/análise , Nanopartículas/efeitos da radiação , Nanopartículas/ultraestrutura , Tamanho da Partícula , Semicondutores , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfetos/análise , Sulfetos/química , Sulfetos/efeitos da radiação , Tiocarbamatos/química , Tioureia/química , Água/química , Difração de Raios X , Compostos de Zinco/análise , Compostos de Zinco/química , Compostos de Zinco/efeitos da radiação , Óxido de Zinco/química
20.
Transplant Proc ; 38(7): 2001-2, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16979978

RESUMO

The course of pregnancy and its outcome was studied in renal allograft recipients. Between November 1985 and November 2005, a total of 1481 renal transplants were carried out at the Sindh Institute of Urology and Transplantation (SIUT); among them were 348 females, with 73 potential females for pregnancy. All patients received cyclosporine and prednisolone, with 82% also receiving azathioprine and 4 patients mycophenolate mofetil as a third immunosuppressant drug. We evaluated incidence of hypertension, diabetes, pre-eclampsia, urinary tract infection (UTI), rejection during pregnancy and during 3 months' postdelivery as well as outcomes of pregnancy. Among 73 potential candidates, 31 had 47 pregnancies, after an average of 31 months (8-86 months). Of 31 subjects, 21 subjects were hypertensive on one or two drugs prior to conception. A rise in blood pressure during pregnancy was noticed in 7 patients. Albuminuria from trace to 3+ appeared in 13 patients and glycosuria in one other. Blood sugar levels remained within normal range in all subjects. UTIs occurred during pregnancy in 7 patients. Among 47 pregnancies, 9 had abortions (7 spontaneous, 2 therapeutic) and 6 had preterm deliveries. The others were full-term deliveries: 12 via a lower segment caesarean section and 20 were normal vaginal deliveries. Average birth weight was 4.8 lbs. At an average follow-up of 38 months the serum creatinine values ranged from 0.94 to 2.3 mg %. One patient developed acute irreversible graft dysfunction soon after delivery. Our study demonstrated that pregnancy did not reduce renal graft survival, but newborns are at greater risk of premature birth and low birth weight.


Assuntos
Transplante de Rim , Complicações na Gravidez , Albuminúria/epidemiologia , Cesárea/estatística & dados numéricos , Parto Obstétrico , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Recém-Nascido , Recém-Nascido Prematuro , Gravidez , Estudos Retrospectivos , Resultado do Tratamento
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