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1.
Asian J Psychiatr ; 97: 104072, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38815437

RESUMO

BACKGROUND: Physical exercise can improve outcomes for people with first-episode psychosis (FEP). Co-designing physical exercise interventions with end users has the potential to enhance their acceptability, feasibility, and long-term viability. This study's objective was to use experience-based co-design (EBCD) methodology to develop a physical exercise intervention for FEP, and pilot test it. METHODS: The study was conducted at the Schizophrenia Research Foundation's FEP program in Chennai, India. Participants(N=36) were individuals with FEP and their caregivers, mental health professionals (MHPs, and physical training experts. EBCD methodology included one-to-one interviews, focus group discussions, joint conferences, and co-design workshops. Two instructional videos were developed. Twelve FEP patients engaged in physical exercise with help of the videos over three months. They were followed up through weekly phone calls and in-person interviews to capture data on regularity, frequency, location of exercise, and comfort levels. RESULTS: Several touch points emerged from the interviews, focus groups, and joint meetings including lack of motivation, knowledge about physical exercise; differing perspectives about physical exercise; limited resource, and time constraints. Two instructional videos demonstrating activities for participants incorporated strategies that addressed these touch points. Pilot data indicated that participants engaged with the physical exercise intervention over 3 months. CONCLUSION: This was the first study to use co-design methodology to design a physical exercise intervention for first-episode psychosis. The intervention may have therefore been responsive to stakeholder needs and preferences. Results of this study highlight the potential of co-design in designing and adapting interventions. There is need for rigorous testing with larger samples.


Assuntos
Terapia por Exercício , Transtornos Psicóticos , Humanos , Transtornos Psicóticos/terapia , Transtornos Psicóticos/reabilitação , Projetos Piloto , Masculino , Adulto , Feminino , Índia , Terapia por Exercício/métodos , Adulto Jovem , Exercício Físico
2.
J Biomed Mater Res B Appl Biomater ; 112(1): e35324, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37638675

RESUMO

The study reports on the use of sol-gel technique to yield zircon type [Zr(1-0.1-x) GdxTi0.1 ] [(SiO4 )1-x (PO4 )x ] solid solution. Titanium has been used as a mineralizer to trigger zircon formation while equimolar concentrations of Gd3+ and PO4 3- were added to determine their accommodation limits in the zircon structure. The crystallization of t-ZrO2 as a dominant phase alongside the crystallization of m-ZrO2 and zircon were detected at 1200°C while their further annealing revealed the formation of zircon as a major phase at 1300°C. Heat treatment at 1400°C revealed the formation of zircon-type solid solution [Zr(1-0.1-x) Gdx Ti0.1 ][(SiO4 )1-x (PO4 )x ] comprising the accommodation of 10 mol.% of Gd3+ /PO4 3- at the zircon lattice. Beyond 10 mol.% of Gd3+ /PO4 3- , the crystallization of GdPO4 as a secondary phase is noticed. Structural analysis revealed the expansion of zircon lattice due to the simultaneous occupancy of Gd3+ /PO4 3- for the corresponding Zr4+ /SiO4 4- sites. The mechanical strength of single-phase zircon solid solution was higher in comparison to that of multiphase materials, namely in the presence of GdPO4 formed as a secondary phase in samples with added equimolar Gd3+ /PO4 3- contents beyond 10 mol.%. Nevertheless, the paramagnetic behavior of the samples demonstrated a steady surge as a function of enhanced Gd3+ content.


Assuntos
Silicatos , Zircônio , Zircônio/química , Cristalização , Fenômenos Magnéticos
3.
Nanoscale Adv ; 5(18): 5054-5076, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37705779

RESUMO

With the ultimate goal of providing a novel platform able to inhibit bacterial adhesion, biofilm formation, and anticancer properties, cerium-doped hydroxyapatite films enhanced with magnetite were developed via spin-coating. The unique aspect of the current study is the potential for creating cerium-doped hydroxyapatite/Fe3O4 coatings on a titanium support to enhance the functionality of bone implants. To assure an increase in the bioactivity of the titanium surface, alkali pretreatment was done before deposition of the apatite layer. Scanning electron microscopy (SEM) in conjunction with energy-dispersive X-ray (EDX) spectroscopy, X-ray diffraction (XRD) analysis, and Fourier transform-infrared (FTIR) spectroscopy were used to evaluate coatings. Coatings demonstrated good efficacy against Staphylococcus aureus and Escherichia coli, with the latter showing the highest efficacy. In vitro bioactivity in simulated body fluid solution showed this material to be proficient for bone-like apatite formation on the implant surface. Electrochemical impedance spectroscopy was undertaken on intact coatings to examine the barrier properties of composites. We found that spin-coating at 4000 rpm could greatly increase the total resistance. After seeding with osteoblastic populations, Ce-HAP/Fe3O4 materials the adhesion and proliferation of cells. The heating capacity of the Ce-HAP/Fe3O4 film was optimal at 45 °C at 15 s at a frequency of 318 kHz. Osseointegration depends on many more parameters than hydroxyapatite production, so these coatings have significant potential for use in bone healing and bone-cancer therapy.

4.
Polymers (Basel) ; 15(1)2022 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-36616505

RESUMO

The research on extracellular matrix (ECM) is new and developing area that covers cell proliferation and differentiation and ensures improved cell viability for different biomedical applications. Extracellular matrix not only maintains biological functions but also exhibits properties such as tuned or natural material degradation within a given time period, active cell binding and cellular uptake for tissue engineering applications. The principal objective of this study is classified into two categories. The first phase is optimization of various electrospinning parameters with different concentrations of HAP-HPC/PLA(hydroxyapatite-hydroxypropylcellulose/poly lactic acid). The second phase is in vitro biological evaluation of the optimized mat using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay for bone regeneration applications. Conductivity and dielectric constant were optimized for the production of thin fiber and bead free nanofibrous mat. With this optimization, the mechanical strength of all compositions was found to be enhanced, of which the ratio of 70:30 hit a maximum of 9.53 MPa (megapascal). Cytotoxicity analysis was completed for all the compositions on MG63 cell lines for various durations and showed maximum cell viability on 70:30 composition for more than 48 hrs. Hence, this investigation concludes that the optimized nanofibrous mat can be deployed as an ideal material for bone regenerative applications. In vivo study confirms the HAP-HPC-PLA sample shows more cells and bone formation at 8 weeks than 4 weeks.

5.
J Biomed Mater Res A ; 107(3): 610-620, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30408314

RESUMO

In the present investigation, the natural cellulose was extracted from Luffa cylindrica vegetable sponge by chemical modification. Both chemically modified and unmodified Luffa was characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy. The chemically modified cellulose was used for the preparation of a nanofibrous scaffold using the electrospinning method. In order to achieve the uniform and bead free fibers with desired fiber diameter the parameters such as applied voltage, tip to collector distance, solution concentration were optimized. Different ratio of hydroxyapatite (HAP): polylactic acid (PLA) such as 40:60, 50:50, 60:40, and 70:30 have been selected for the current evaluation and was compared with HAP-treated cellulose (TC)-PLA. With the increase in the concentration of HAP in the polymeric network, the diameter of the fiber was found to be thin with the high electric field. The functional group, phase formation and dielectric and mechanical properties of the developed nanofiber have been characterized by FTIR, XRD, mechanical property measurements, and SEM. From the results, we observed that the polymer composite developed with the ratio of 70:30 produces a bead free product with enhanced mechanical and bioactivity property by the formation of hydroxy carbonated apatite layer on the surface. All the nanofibrous scaffold fabricated with and without modification have shown good Cyto compatibility on MG-63 Osteoblast cell lines at 48 hr. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 610-620, 2019.


Assuntos
Celulose , Durapatita , Luffa/química , Teste de Materiais , Nanofibras/química , Osteoblastos/metabolismo , Poliésteres , Animais , Linhagem Celular Tumoral , Celulose/química , Celulose/farmacologia , Durapatita/química , Durapatita/farmacologia , Camundongos , Osteoblastos/citologia , Poliésteres/química , Poliésteres/farmacologia
6.
J Biomed Mater Res A ; 106(12): 3267-3274, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30289613

RESUMO

Cancellous bone region of the human native bone has the potential to bear significant mechanical loads. However, due to the following parameters such as low trabecular volume, more porosity, less thickness and more interconnectivity, cancellous bone is accessible to damage in accidents or when aging. This research led to the effective fabrication and engineering of cancellous region of the bone for its application in reconstruction or filling of bone voids after resection of large tumor mass. Scaffolds containing hydroxyapatite (HAp), polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) (5% polymer and HAp concentrations) at different HAp: polymer composite ratios (50:50, 70:30 and 80:20), were fabricated by freeze-drying method using only water as solvent and ribose as crosslinker for the scaffolds. The fabricated scaffolds were characterized for its mechanical (compressive) strength, chemical properties using FT-IR and XRD analyses, swelling and degradation studies, confirmation of mineralization process by immersion in simulated body fluid (SBF) for 7, 15 and 30 days, morphological analysis using scanning electron microscopy (SEM), and biocompatibility properties by performing MTT analysis. From the combined interpretation of the above mentioned tests, it was proven that 80:20 ratio of HAp to polymers was found to be the most suitable scaffold in terms of its optimal properties for its use as bone graft material for trabecular bone. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3267-3274, 2018.


Assuntos
Substitutos Ósseos/química , Durapatita/química , Álcool de Polivinil/química , Povidona/química , Alicerces Teciduais/química , Animais , Sobrevivência Celular , Dureza , Humanos , Teste de Materiais , Camundongos , Estresse Mecânico , Engenharia Tecidual/métodos
7.
Mater Sci Eng C Mater Biol Appl ; 71: 879-890, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27987785

RESUMO

Novel bioceramics have an intriguing role in implants and prostheses as surface protecting agents. These bioceramics have promising features such as biocompatible, bioactive, and corrosion-resistant natures. Among bioceramics, silica glass and its composite unravel its better desirability against corrosion and wear with interfacial bone bonding capability in physiological systems by nucleating calcium phosphates over the surface, thereby enhancing the osteoinductive property. In the current study, SiO2 and ZnO were obtained by processing silica and zinc oxide precursors at low temperature using low thermal volatilization sol-gel method. SiO2, ZnO, and its composite powders were characterized by Fourier transform infrared spectroscopy (FT-IR), powder X-ray diffraction (XRD), and scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDAX). Electrophoretic deposition (EPD) was used for coating on Ti-6Al-4V for improved coating characteristics. In addition, the effect of additives such as iodine and Polyvinylpyrrolidone (PVP) on coating limits was also optimized. Thin-film XRD, Optical Microscopy, SEM-EDAX, Raman spectroscopy, and the scratch resistance test characterized the coating. Tafel polarization and electrochemical impedance spectroscopy (EIS) studies were also carried out to assess corrosion resistance behaviour of the coating. The results showed that the composite coating has greater corrosion resistance than uncoated Ti-6Al-4V. Furthermore, improved mechanical property with better scratch resistance was also observed. These observations showed that composite coating could be useful in biomedical applications.


Assuntos
Materiais Revestidos Biocompatíveis/química , Dióxido de Silício/química , Titânio/química , Ligas , Corrosão , Eletroforese , Povidona/análogos & derivados , Povidona/química
8.
Int J Nanomedicine ; 10 Suppl 1: 31-41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26491305

RESUMO

The purpose of this study is to prepare and evaluate the effect of synthesized titanium dioxide (TiO2) nanoparticles for their biocompatibility on physiological body fluids and the effect of cell toxicity to produce osteointegration when used as implantable materials. For the past few decades, the number of researches done to understand the importance of the biocompatibility of bioceramics, metals, and polymers and their effect on clinical settings of biomedical devices has increased. Hence, the total concept of biocompatibility encourages researchers to actively engage in the investigation of the most compatible materials in living systems by analyzing them using suitable physical, chemical, and biological (bioassay) methods. The ceramic material nano TiO2 was prepared by sol-gel method and analyzed for its functional group and phase formation by Fourier transform infrared spectroscopy and powder X-ray diffraction. Furthermore, the particle size, shape, surface topography, and morphological behavior were analyzed by dynamic light scattering, zeta potential, scanning electron microscopy-energy dispersive X-ray analysis, and transmission electron microscopy analysis. In addition to this, the cytotoxicity and cytocompatibility were determined on MG63 cell lines with varying doses of concentrations such as 1 µg/mL, 10 µg/mL, 25 µg/mL, 50 µg/mL, and 100 µg/mL with different time periods such as 24 hours and 48 hours. The results have not shown any toxicity, whereas, it improved the cell viability/proliferation at various concentrations. Hence, these findings indicate that the nano TiO2 material acts as a good implantable material when used in the biomedical field as a prime surface-modifying agent.


Assuntos
Nanopartículas/toxicidade , Nanotecnologia/métodos , Titânio/farmacologia , Materiais Biocompatíveis/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Difusão Dinâmica da Luz , Humanos , Nanopartículas/ultraestrutura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Tamanho da Partícula , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Difração de Raios X
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 139: 515-20, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25576950

RESUMO

The major interest of the paper deals with the extraction of silica from four natural sources such as rice husk, bamboo leaves, sugarcane bagasse and groundnut shell. These waste materials in large quantities can create a serious environmental problem. Hence, there is a need to adopt proper strategy to reduce the waste. In the present investigation, all the waste materials are subjected to moisture removal in a hot plate and sintered at 900°C for 7 h. The sintered powder was treated with 1 M NaOH to form sodium silicate and then with 6M H2SO4 to precipitate silica. The prepared silica powders were characterized by FT-IR, XRD and SEM-EDAX analysis. The silica recovered from different sources was found to vary between 52% and 78%. Magnesium substituted silica was formed from the groundnut waste and further treatment is required to precipitate silica.


Assuntos
Agricultura , Nanopartículas/química , Dióxido de Silício/química , Resíduos/análise , Microscopia Eletrônica de Varredura , Hidróxido de Sódio/química , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Ácidos Sulfúricos/química , Temperatura , Difração de Raios X
10.
J Fluoresc ; 24(4): 1297-306, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24912449

RESUMO

Donor-linker-acceptor (DSSA) is a concept in fluorescence chemistry with acceptor being a fluorescent compound (FRET) or quencher. The DSSA probes used to measure thiol levels in vitro and in vivo. The reduction potential of these dyes are in the range of -0.60 V, much lower than the best thiol reductant reported in literature, the DTT (-0.33 V). DSSA disulphide having an unusually low reduction potential compared to the typical thiol reductants is a puzzle. Secondly, DSSA probes have a cyclized rhodamine ring as acceptor which does not have any spectral overlap with fluorescein, but quenches its absorbance and fluorescence. To understand the structural features of DSSA probes, we have synthesized DSSANa and DSSAOr. The calculated reduction potential of these dyes suggest that DSSA probes have an alternate mechanism from the FRET based quenching, namely hydrophobic interaction or dye to dye quenching. The standard reduction potential change with increasing complexity and steric hindrance of the molecule is small, suggesting that ultra- low Eo' has no contribution from the disulphide linker and is based on structural interactions between fluorescein and cyclized rhodamine. Our results help to understand the DSSA probe quenching mechanism and provide ways to design fluorescent probes.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular
11.
Case Rep Dent ; 2013: 631284, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24024045

RESUMO

Introduction. The temporomandibular joint (TMJ) is the most complex elegantly designed joint in the human body. Abnormal development and growth of TMJ may lead to condyle aplasia present in several syndromes expressions, but it is extremely rare when not connected to any underlying pathological disorder or in conjunction with any syndrome. Objective. A rare case of aplasia of the mandibular condyle is presented, along with 3D computed tomography (3D CT) findings. Conclusion. Based on clinical and radiological findings we suggest the abnormal development of the TMJ as the origin. The 3D CT has provided high-quality images, which made diagnosis and a prompt treatment plan possible.

12.
J Biomed Mater Res A ; 87(3): 739-49, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18200538

RESUMO

Metallic materials having good mechanical properties, high corrosion resistance, and good compatibility with biological materials are used as orthopedic devices. Type 316L stainless steel is the most widely used material for implant fabrication in India for orthopedic applications owing to their good corrosion resistance, hot and cold workability, excellent mechanical properties, and availability at low cost. However, it faces corrosion-related problems in physiological environment and thus releases toxic metal ions into the tissues surrounding the implants. Hence, hydroxyapatite (HAP) coatings over the metal implant have been developed as an alternative method to improve the surface conditions of the base metal. In the present investigation, the development of a sol-gel-derived hydroxyapatite coating on 316L SS is being explored. The corrosion resistance behavior of the coating was assessed through electrochemical studies involving cyclic polarization experiments and impedance analysis in Ringer's solution. The results have indicated that the sol-gel-derived HAP coatings exhibited excellent resistance to localized attack on pristine 316L SS.


Assuntos
Materiais Revestidos Biocompatíveis/química , Durapatita/química , Géis/química , Aço Inoxidável/química , Corrosão , Impedância Elétrica , Eletroquímica/métodos , Soluções Isotônicas , Teste de Materiais , Solução de Ringer , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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