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2.
Med J Malaysia ; 78(4): 534-540, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37518929

RESUMO

INTRODUCTION: The meniscus plays an important role in maintaining homeostasis to facilitate the normal function of the knee joint. It is one of the most commonly injured areas of the knee joint. Meniscal-related injuries can lead to significantly decreased athletic ability, and their incidence has increased yearly. It has been found that most meniscal injuries are irreparable, and meniscectomy can increase the predisposition to knee osteoarthritis. Tissue engineering technology on meniscus repairing and transplantation has received widespread attention recently. This review aimed to analyse the scientific literature regarding the potential applications of tissue engineering on meniscus repairing and transplantation procedures. METHOD AND MATERIALS: The electronic search was carried out using PubMed/MEDLINEⓇdatabases with the keywords "tissue engineering AND meniscus" spanning the period of publications from Jan 1980 until Dec 2022. RESULTS: The literature search identified 405 references in PubMed/MEDLINE, and 179 were selected following the eligibility requirements. The research analysis showed that the existing meniscal tissue engineering studies used a wide variety of seed cells, cytokines, bioactive materials and 3D structures. Each showed distinct advantages and disadvantages in terms of biocompatibility, degradability, mechanical strength, porosity, and etc. It was noted that 3D printing technology is promising for tissue engineering meniscus research. In addition, the optimal use of compression and hydrostatic pressure to markedly improve the functional properties of tissue-engineering meniscal can serve as an useful strategy. CONCLUSION: This review analysed the different approaches employed for meniscus tissue engineering and regeneration. Meniscal tissue engineering still faces several major challenges in terms of seed cells, choice of materials and 3D printing strategies, which should be effectively overcome to harness the full potential of this technology.

3.
Bioinorg Chem Appl ; 2023: 8626155, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36779008

RESUMO

Nowadays, scarcity arises in almost all our basic needs, including water, fuel, and food. Recycling used and scrapped things for a valuable commodity is highly appreciable for compensating for the globally fast-growing demand. This paper aims to investigate waste tyre oil for preparing biodiesel for CI engines by enhancing their performance with hybrid nanoparticles for preparing nanofuel and hybrid nanofuel. The nanoparticles (30-40 nm) of MWCNT and TiO2 were utilized to prepare nanofuels with nanoparticle concentrations of MWCNT (300 ppm) and TiO2 (300 ppm), respectively. In the case of hybrid nanofuel, the nanoparticle concentration of MWCNT (150 ppm) and TiO2 (150 ppm) was preferred. The performance of the proposed nanofuel and hybrid nanofuel with pure diesel was evaluated. The proposed fuel performance outperforms the combustion performance, has higher engine efficiency, and has fewer emissions. The best performances were noticed in hybrid nanofuel that has 32% higher brake thermal efficiency than diesel and 24% and 4% lower BSFC and peak pressure than diesel, respectively. The emission performance is also 29%, 50%, and 13% lower in CO, HC, and CO2 emissions than that in pure diesel.

4.
Cureus ; 13(2): e13174, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33717719

RESUMO

The gene PTRH2 encodes a protein with peptidyl-tRNA hydrolase activity and is involved in the translation process in protein synthesis. The kinesin family member 1-A (KIF1A) gene encodes a molecular motor involved in axonal transport along microtubules. Mutations in these genes lead to respective phenotypical conditions that have been reported in the literature. In this paper, we present a novel syndrome of concurrent occurrence of mutations in the PTRH2 and KIF1A genes in a 19-year-old girl of Dravidian-Tamil descent from the Southern part of India. The girl presented with global developmental delay, intellectual disability, weakness of upper and lower limbs, and diabetes. On workup, she was found to have severe peripheral axonopathy, outer hair cell (OHC) dysfunction, severe bilateral sensorineural hearing loss (SNHL), total pancreatic lipomatosis, exocrine pancreatic insufficiency, cerebellar atrophy, vertebral artery hypoplasia, and scoliosis. The patient had a deceased elder sibling who also had had a similar phenotype. Whole exome sequencing (WES) revealed a novel variant in the PTRH2 gene and a rare variant in the KIF1A gene. The predominant axonal involvement seen in our patient, which was attributable to KIF1A involvement, distinguishes this syndrome from the infantile-onset multisystem neurologic, endocrine, and pancreatic disease (IMNEPD) caused by PTRH2 involvement alone. To the best of our knowledge, this is the first report in the medical literature of a syndrome caused by the synergistic occurrence of mutations in the PTRH2 and KIF1A genes. In order to provide more clarity on the genetic and clinical features of such syndromes and to aid the treating clinician to recognize the existence of such syndromes, we propose the broader umbrella term "neuro-pancreatic syndromes" (NPS). Presently, under NPS, we include two entities: the syndrome described by us in this paper and the IMNEPD. Prompt and effective recognition and management of such NPS would immensely benefit the patient in terms of treatment and prognosis. Furthermore, we hope that this paper will promote further understanding of NPS and foster more research, both clinical and genetic, which would widen the spectrum of NPS. Eventually, this would throw more light on treatment options and ultimately benefit patients with NPS.

5.
Int J Biol Macromol ; 165(Pt B): 3088-3105, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33098896

RESUMO

Chitosan, collagen, gelatin, polylactic acid and polyhydroxyalkanoates are notable examples of biopolymers, which are essentially bio-derived polymers produced by living cells. With the right techniques, these biological macromolecules can be exploited for nanotechnological advents, including for the fabrication of nanocarriers. In the world of nanotechnology, it is highly essential (and optimal) for nanocarriers to be biocompatible, biodegradable and non-toxic for safe in vivo applications, including for drug delivery, cancer immunotherapy, tissue engineering, gene delivery, photodynamic therapy and many more. The recent advancements in understanding nanotechnology and the physicochemical properties of biopolymers allows us to modify biological macromolecules and use them in a multitude of fields, most notably for clinical and therapeutic applications. By utilizing chitosan, collagen, gelatin, polylactic acid, polyhydroxyalkanoates and various other biopolymers as synthesis ingredients, the 'optimal' properties of a nanocarrier can easily be attained. With emphasis on the aforementioned biological macromolecules, this review presents the various biopolymers utilized for nanocarrier synthesis along with their specific synthetization methods. We further discussed on the characterization techniques and related applications for the synthesized nanocarriers.


Assuntos
Biopolímeros/química , Portadores de Fármacos/química , Poliésteres/química , Polissacarídeos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/uso terapêutico , Biopolímeros/uso terapêutico , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos/tendências , Humanos , Nanotecnologia/tendências , Poliésteres/uso terapêutico , Polissacarídeos/uso terapêutico , Proteínas/química , Proteínas/uso terapêutico , Engenharia Tecidual/tendências
6.
BMC Public Health ; 19(1): 69, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30646867

RESUMO

BACKGROUND: In 2016, the Government of India introduced the oral rotavirus vaccine (ROTAVAC, Bharat Biotech, India) in 4 states of India as part of the Universal Immunization Programme, and expanded to 5 more states in 2017. We report four years of data on rotavirus gastroenteritis in hospitalized children < 5 years of age prior to vaccine introduction. METHODS: Children from 7 sites in southern and northern India hospitalized for diarrhoea were recruited between July 2012 and June 2016. Stool samples were screened for rotavirus using enzyme immunoassay (EIA). The EIA positive samples were genotyped by reverse-transcription polymerase chain reaction. RESULTS: Of the 5834 samples from the 7 sites, 2069 (35.5%) were positive for rotavirus by EIA. Genotyping was performed for 2010 (97.1%) samples. G1P[8](56.3%), G2P[4](9.1%), G9P[4](7.6%), G9P[8](4.2%), and G12P[6](3.7%) were the common genotypes in southern India and G1P[8](36%), G9P[4](11.4%), G2P[4](11.2%), G12P[6](8.4%), and G3P[8](5.9%) in northern India. CONCLUSIONS: The study highlights the high prevalence of rotavirus gastroenteritis in India and the diversity of rotavirus genotypes across different geographical regions. Pre- vaccine surveillance data is necessary to evaluate the potential change in admission rates for gastroenteritis and circulating rotavirus genotypes after vaccine introduction, thus assessing impact.


Assuntos
Diarreia/virologia , Fezes/virologia , Gastroenterite/virologia , Genótipo , Infecções por Rotavirus/virologia , Vacinas contra Rotavirus , Rotavirus/genética , Pré-Escolar , Diarreia/epidemiologia , Diarreia/etiologia , Infecções por Enterovirus , Feminino , Gastroenterite/complicações , Gastroenterite/epidemiologia , Hospitalização , Humanos , Programas de Imunização , Índia/epidemiologia , Lactente , Masculino , Prevalência , Características de Residência , Rotavirus/crescimento & desenvolvimento , Infecções por Rotavirus/complicações , Infecções por Rotavirus/epidemiologia , Vacinação
7.
J Immunol Res ; 2018: 3430684, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30155492

RESUMO

Alternanthera sessilis, an edible succulent herb, has been widely used as herbal drug in many regions around the globe. Inflammation is a natural process of the innate immune system, accompanied with the increase in the level of proinflammatory mediators, for example, nitric oxide (NO) and prostaglandin (PGE2); cytokines such as interleukin 6 (IL-6), interleukin 1ß (IL-1ß), and tumor necrosis factor alpha (TNFα); and enzymes including inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) via the activation and nuclear translocation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) subunit p65 due to the phosphorylation of inhibitory protein, IκBα. Inflammation over a short period of time is essential for its therapeutic effect. However, prolonged inflammation can be detrimental as it is related to many chronic diseases such as delayed wound healing, cardiovascular disease, arthritis, and autoimmune disorders. Therefore, ways to curb chronic inflammation have been extensively investigated. In line with that, in this present study, we attempted to study the suppression activity of the proinflammatory cytokines and mediators as a characteristic of anti-inflammatory action, by using stem extract of A. sessilis in the lipopolysaccharide- (LPS-) stimulated RAW 264.7 macrophage cell line. The results showed that the extract has significantly inhibited the production of the proinflammatory mediators including NO and PGE2; cytokines comprising IL-6, IL-1ß, and TNFα; and enzymes covering the iNOS and COX-2 by preventing the IκBα from being degraded, to inhibit the nuclear translocation of NF-κB subunit p65 in order to hinder the inflammatory pathway activation. These results indicated that the stem extract of A. sessilis could be an effective candidate for ameliorating inflammatory-associated complications.


Assuntos
Amaranthaceae/imunologia , Anti-Inflamatórios/farmacologia , Macrófagos/imunologia , NF-kappa B/metabolismo , Extratos Vegetais/farmacologia , Animais , Citocinas/metabolismo , Dinoprostona/metabolismo , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos/imunologia , Macrófagos/efeitos dos fármacos , Camundongos , Óxido Nítrico/metabolismo , Caules de Planta , Células RAW 264.7 , Transdução de Sinais
8.
J Mater Chem B ; 3(18): 3858-3869, 2015 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32262859

RESUMO

The stem cell fates of pluripotency and differentiation are regulated by not only soluble biological cues but also insoluble biochemical cues (i.e., extracellular matrix (ECM)) and the physical cues of cell culture biomaterials (i.e., elasticity). We investigated the maintenance of pluripotency and the differentiation lineages of human amniotic fluid-derived stem cells (hAFSCs) cultured on poly(vinyl alcohol-co-itaconic acid) (PVA) hydrogels grafted with several types of ECM and corresponding oligopeptides in expansion medium. hAFSCs cultured on soft PVA hydrogels (12.2 kPa) that were grafted with oligopeptides derived from fibronectin and vitronectin showed high pluripotency, which was evaluated by Oct4, Sox2 and Nanog expression. The hAFSCs grown on soft PVA hydrogels (12.2 kPa) grafted with each oligopeptide showed higher pluripotency, as assessed by Oct4 and Nanog expression, than hAFSCs grown on stiff PVA hydrogels (25.3 kPa) grafted with the same oligopeptides and a much higher pluripotency than those grown on rigid tissue-culture polystyrene dishes. Soft biomaterials appeared to be adequate to maintain the pluripotency of hAFSCs. Surprisingly, hAFSCs that showed higher pluripotency on PVA hydrogels grafted with oligopeptides derived from fibronectin and vitronectin also expressed higher levels of early differentiation markers for three germ layers in expansion medium. This result suggests that hAFSCs are heterogeneous and that this population contains highly pluripotent stem cells and stem cells that can be easily differentiated.

9.
Biomaterials ; 35(14): 4278-87, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24565521

RESUMO

The purification of human adipose-derived stem cells (hADSCs) from human adipose tissue cells (stromal vascular fraction) was investigated using membrane filtration through poly(lactide-co-glycolic acid)/silk screen hybrid membranes. Membrane filtration methods are attractive in regenerative medicine because they reduce the time required to purify hADSCs (i.e., less than 30 min) compared with conventional culture methods, which require 5-12 days. hADSCs expressing the mesenchymal stem cell markers CD44, CD73, and CD90 were concentrated in the permeation solution from the hybrid membranes. Expression of the surface markers CD44, CD73, and CD99 on the cells in the permeation solution from the hybrid membranes, which were obtained using 18 mL of feed solution containing 50 × 104 cells, was statistically significantly higher than that of the primary adipose tissue cells, indicating that the hADSCs can be purified in the permeation solution by the membrane filtration method. Cells expressing the stem cell-associated marker CD34 could be successfully isolated in the permeation solution, whereas CD34⁺ cells could not be purified by the conventional culture method. The hADSCs in the permeation solution demonstrated a superior capacity for osteogenic differentiation based on their alkali phosphatase activity, their osterix gene expression, and the results of mineralization analysis by Alizarin Red S and von Kossa staining compared with the cells from the suspension of human adipose tissue. These results suggest that the hADSCs capable of osteogenic differentiation preferentially permeate through the hybrid membranes.


Assuntos
Tecido Adiposo/citologia , Ácido Láctico/farmacologia , Membranas Artificiais , Ácido Poliglicólico/farmacologia , Seda/farmacologia , Células-Tronco/citologia , Idoso , Idoso de 80 Anos ou mais , Animais , Biomarcadores/metabolismo , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Separação Celular , Filtração , Citometria de Fluxo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Microscopia Eletrônica de Varredura , Pessoa de Meia-Idade , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Soluções , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo
10.
J Biomed Mater Res B Appl Biomater ; 102(3): 463-76, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24039170

RESUMO

Cancer-initiating cells [cancer stem cells (CSCs)] in colon cancer cells can be selectively suppressed when they are cultured on Pluronic (nanosegment)-grafted dishes, whereas CSCs are maintained on conventional tissue culture dishes and extracellular matrix-coated dishes. CSCs persist in tumors as a distinct population and cause relapse and metastasis by giving rise to new tumorigenic clones. The purification or depletion (suppression) of CSCs should be useful for analyzing CSC characteristics and for clinical application. CSCs can be selectively suppressed from colon cancer cells containing adipose-derived stem cells (ADSCs) on Pluronic-grafted dishes, while ADSCs remain on the dishes. ADSCs on Pluronic-grafted dishes after the suppression of the CSCs can differentiate into osteoblasts, chondrocytes, adipocytes, cardiomyocytes, and neuronal cells. The CSCs and ADSCs exhibited different characteristics. The selection of ADSCs was possible on Pluronic-grafted dishes that suppressed the CSCs from the fat tissues of cancer patients (i.e., cell-sorting dishes), which was explained by specific biomedical characteristics of Pluronic.


Assuntos
Adipócitos/fisiologia , Materiais Biocompatíveis , Células-Tronco Neoplásicas/fisiologia , Células-Tronco/fisiologia , Idoso , Idoso de 80 Anos ou mais , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Células Cultivadas , Neoplasias do Colo/patologia , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Imuno-Histoquímica , Camundongos , Pessoa de Meia-Idade , Transplante de Neoplasias , Poloxâmero , Poliestirenos
11.
Biomaterials ; 33(33): 8228-39, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22940220

RESUMO

Human adipose-derived stem cells (hADSCs) were purified from a suspension of human adipose tissue cells (stromal vascular fraction) by the conventional culture method and by membrane filtration through polyurethane (PU) foam membranes. hADSCs can be obtained from a suspension of human adipose tissue cells using the membrane filtration method in less than 30 min, whereas the conventional culture method requires 5-12 days. hADSCs that express the mesenchymal stem cell markers CD44, CD73, and CD90 were concentrated in the recovery solution from the PU membranes; no hADSCs were isolated in the permeate. After filtration, the cells expressing the mesenchymal stem cell markers were 3-4.5 times more concentrated than in the initial suspension of human adipose tissue cells, with the level of concentration depending on the surface modification of the PU membrane. Cells expressing the stem cell-associated marker CD34 could be successfully isolated in the recovery solutions, whereas CD34(+) cells could not be purified by the conventional culture method. The hADSCs in the recovery solution demonstrated a superior capacity for osteogenic differentiation than did the cells in the suspension of human adipose tissue cells. These results suggested that the hADSCs with the capability for osteogenic differentiation adhered to the PU membranes.


Assuntos
Tecido Adiposo/citologia , Filtração/métodos , Membranas Artificiais , Células-Tronco/citologia , Idoso , Idoso de 80 Anos ou mais , Antígenos CD34/metabolismo , Diferenciação Celular/fisiologia , Células Cultivadas , Humanos , Pessoa de Meia-Idade , Células-Tronco/metabolismo
13.
Indian J Exp Biol ; 46(6): 447-52, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18697603

RESUMO

Ethanol extract and its ethanol fraction from aerial parts of P. daemia exhibited significant hepatoprotective effect against CCl4 induced hepatotoxicity in rats. Glutamic oxaloacetic transaminase, glutamic pyruvic transaminase, alkaline phosphatase, total bilirubin, total cholesterol, total protein and albumin in serum indicated hepatoprotective effect of the ethanol extract and its ethanol fraction. Histopathological examination of liver sections confirmed that, pre-treatment with ethanol extract and its ethanol fraction prevented hepatic damage induced by CCl4. The results were comparable with the standard hepatoprotective drug silymarin. The extract and its fraction showed no signs of toxicity up to a dose level of 2000 mg/kg. It is suggested that, the presence of flavonoids in ethanol extract and its ethanol fraction may be responsible for hepatoprotective properties. High Performance Thin Layer Chromatography profile of flavonoids of bio-active extracts was developed using quercetin-3-glucoside as a marker. Results indicate hepatoprotective properties of ethanol extract of P. daemia.


Assuntos
Apocynaceae , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Fitoterapia , Extratos Vegetais/administração & dosagem , Animais , Doença Hepática Induzida por Substâncias e Drogas/patologia , Relação Dose-Resposta a Droga , Feminino , Masculino , Extratos Vegetais/química , Folhas de Planta , Caules de Planta , Ratos , Silimarina/uso terapêutico
14.
Int J Food Microbiol ; 82(3): 213-21, 2003 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12593924

RESUMO

Bacteriological quality of individually quick frozen (IQF) shrimp products produced from aquacultured tiger shrimp (Penaeus monodon) has been analysed in terms of aerobic plate count (APC), coliforms, Escherichia coli, coagulase-positive staphylococci, Salmonella, and Listeria monocytogenes. Eight hundred forty-six samples of raw, peeled, and deveined tail-on (RPTO), 928 samples of cooked, peeled, and deveined tail-on (CPTO), 295 samples of headless, undeveined shell-on (HLSO), and 141 samples of raw, peeled, and deveined tail-off (RPND) shrimps were analysed for the above bacteriological parameters. Salmonella was isolated in only one sample of raw, peeled tail-on. Serotyping of the strain revealed that it was S. typhimurium. While none of the cooked, peeled tail-on shrimp samples exceeded the aerobic plate count (APC) of 10(5) colony forming units per gram (cfu/g), 2.5% of raw, peeled, tail-on, 6.4% of raw, peeled tail-off, and 7.5% of headless shell-on shrimp samples exceeded that level. Coliforms were detected in all the products, though at a low level. Prevalence of coliforms was higher in headless shell-on (26%) shrimps followed by raw, peeled, and deveined tail-off (19%), raw, peeled tail-on (10%), and cooked, peeled tail-on (3.8%) shrimps. While none of the cooked, peeled tail-on shrimp samples were positive for coagulase-positive staphylococci and E. coli, 0.6-1.3% of the raw, peeled tail-on were positive for staphylococci and E. coli, respectively. Prevalence of staphylococci was highest in raw, peeled tail-off (5%) shrimps and the highest prevalence of E. coli (4.8%) was noticed in headless shell-on shrimps. L. monocytogenes was not detected in any of the cooked, peeled tail-on shrimps. Overall results revealed that the plant under investigation had exerted good process control in order to maintain superior bacteriological quality of their products.


Assuntos
Contaminação de Alimentos/análise , Microbiologia de Alimentos , Penaeidae/microbiologia , Frutos do Mar/microbiologia , Frutos do Mar/normas , Aquicultura , Contagem de Colônia Microbiana , Manipulação de Alimentos/métodos , Alimentos Congelados/microbiologia , Listeria monocytogenes/isolamento & purificação , Salmonella typhimurium/isolamento & purificação , Staphylococcus aureus/isolamento & purificação
15.
Resuscitation ; 50(2): 239-41, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11719153

RESUMO

This case report describes a transdiaphragmatic approach through an already present vertical midline abdominal incision for performing internal cardiac compressions in a 30-year-old male road accident victim. The patient had a flail chest with haemopneumothorax and haemoperitoneum. Exploratory laparotomy followed by splenectomy was performed under general anaesthesia but the patient developed a witnessed cardiac arrest in postoperative period. Successful resuscitation using internal cardiac compression by a transdiaphragmatic approach through the midline abdominal incision that was not extended proximally is described.


Assuntos
Reanimação Cardiopulmonar/métodos , Tórax Fundido/cirurgia , Parada Cardíaca/terapia , Complicações Pós-Operatórias/terapia , Acidentes de Trânsito , Adulto , Diafragma , Tórax Fundido/complicações , Parada Cardíaca/etiologia , Hemoperitônio/complicações , Hemoperitônio/cirurgia , Hemopneumotórax/complicações , Hemopneumotórax/cirurgia , Humanos , Laparotomia , Masculino
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