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1.
Fish Shellfish Immunol ; 149: 109574, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692379

RESUMO

B-cell lymphoma/leukemia-2 (BCL2), an anti-apoptotic factor in the mitochondrial regulatory pathway of apoptosis, is critically important in immune defenses. In this study, a novel BCL2 gene was characterized from Pteria penguin (P. penguin). The PpBCL2 was 1482 bp long, containing an open reading frame (ORF) of 588 bp encoding 195 amino acids. Four highly conserved BCL-2 homology (BH) domains were found in PpBCL2. Amino acid alignment and phylogenetic tree showed that PpBCL2 had the highest similarity with BCL2 of Crassostrea gigas at 65.24 %. Tissue expression analysis showed that PpBCL2 had high constitutive expression in gill, digestive diverticulum and mantle, and was significantly increased 72 h of Vibrio parahaemolyticus (V. parahaemolyticus) challenge in these immune tissues. Furthermore, PpBCL2 silencing significantly inhibited antimicrobial activity of hemolymph supernatant by 1.4-fold, and significantly reduced the survival rate by 51.7 % at 72 h post infection in P. penguin. These data indicated that PpBCL2 played an important role in immune response of P. penguin against V. parahaemolyticus infection.


Assuntos
Sequência de Aminoácidos , Imunidade Inata , Filogenia , Proteínas Proto-Oncogênicas c-bcl-2 , Alinhamento de Sequência , Spheniscidae , Vibrio parahaemolyticus , Animais , Vibrio parahaemolyticus/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/imunologia , Spheniscidae/imunologia , Spheniscidae/genética , Alinhamento de Sequência/veterinária , Imunidade Inata/genética , Regulação da Expressão Gênica/imunologia , Perfilação da Expressão Gênica/veterinária , Vibrioses/imunologia , Vibrioses/veterinária , Sequência de Bases
2.
Heliyon ; 10(4): e26121, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404843

RESUMO

Genome-wide sequencing allows for prediction of clinical treatment responses and outcomes by estimating genomic status. Here, we developed Genomic Status scan (GSscan), a long short-term memory (LSTM)-based deep-learning framework, which utilizes low-pass whole genome sequencing (WGS) data to capture genomic instability-related features. In this study, GSscan directly surveys homologous recombination deficiency (HRD) status independent of other existing biomarkers. In breast cancer, GSscan achieved an AUC of 0.980 in simulated low-pass WGS data, and obtained a higher HRD risk score in clinical BRCA-deficient breast cancer samples (p = 1.3 × 10-4, compared with BRCA-intact samples). In ovarian cancer, GSscan obtained higher HRD risk scores in BRCA-deficient samples in both simulated data and clinical samples (p = 2.3 × 10-5 and p = 0.039, respectively, compared with BRCA-intact samples). Moreover, HRD-positive patients predicted by GSscan showed longer progression-free intervals in TCGA datasets (p = 0.0011) treated with platinum-based adjuvant chemotherapy, outperforming existing low-pass WGS-based methods. Furthermore, GSscan can accurately predict HRD status using only 1 ng of input DNA and a minimum sequencing coverage of 0.02 × , providing a reliable, accessible, and cost-effective approach. In summary, GSscan effectively and accurately detected HRD status, and provide a broadly applicable framework for disease diagnosis and selecting appropriate disease treatment.

3.
Ecotoxicol Environ Saf ; 266: 115610, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37866036

RESUMO

Cadmium (Cd) exposure damages the reproductive system. Lipid droplets (LDs) play an important role in steroid-producing cells to provide raw material for steroid hormone. We have found that the LDs of Leydig cells exposed to Cd are bigger than those of normal cells, but the effects on steroidogenesis and its underlying mechanism remains unclear. Using Isobaric tag for relative and absolute quantitation (iTARQ) proteomics, phosphodiesterase beta-2 (PLCß2) was identified as the most significantly up-regulated protein in immature Leydig cells (ILCs) and adult Leydig cells (ALCs) derived from male rats exposed to maternal Cd. Consistent with high expression of PLCß2, the size of LDs was increased in Leydig cells exposed to Cd, accompanied by reduction in cholesterol and progesterone (P4) levels. However, the high PLCß2 did not result in high diacylglycerol (DAG) level, because Cd exposure up-regulated diacylglycerol kinases ε (DGKε) to promote the conversion from DAG to phosphatidic acid (PA). Exogenous PA, which was consistent with the intracellular PA concentration induced by Cd, facilitated the formation of large LDs in R2C cells, followed by reduced P4 level in the culture medium. When PLCß2 expression was knocked down, the increased DGKε caused by Cd was reversed, and then the PA level was decreased to normal. As results, large LDs returned to normal size, and the level of total cholesterol was improved to restore steroidogenesis. The accumulation of PA regulated by PLCß2-DAG-DGKε signal pathway is responsible for the formation of large LDs and insufficient steroid hormone synthesis in Leydig cells exposed to Cd. These data highlight that LD is an important target organelle for Cd-induced steroid hormone deficiency in males.


Assuntos
Cádmio , Células Intersticiais do Testículo , Ratos , Masculino , Animais , Células Intersticiais do Testículo/metabolismo , Cádmio/toxicidade , Cádmio/metabolismo , Gotículas Lipídicas/metabolismo , Fosfolipase C beta/metabolismo , Ácidos Fosfatídicos/metabolismo , Diglicerídeos/metabolismo , Transdução de Sinais , Esteroides/metabolismo , Progesterona/metabolismo , Colesterol/metabolismo
4.
Cancer Genet ; 272-273: 35-40, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36758499

RESUMO

Homologous recombination repair deficiency (HRD) results in a defect in DNA repair and is a frequent driver of tumorigenesis. Poly(ADP-ribose) polymerase inhibitors (PARPi) or platinum-based therapies have increased theraputic effectiveness when treating HRD positive cancers. For breast cancer and ovairan cancer HRD companion diagnostic tests are commonly used. However, the currently used HRD tests are based on high-depth genome sequencing or hybridization-based capture sequencing, which are technically complex and costly. In this study, we modified an existing method named shallowHRD, which uses low-pass whole genome sequencing (WGS) for HRD detection, and estimated the performance of the modified shallowHRD pipeline. Our shallowHRD pipeline achieved an AUC of 0.997 in simulated low-pass WGS data, with a sensitivity of 0.981 and a specificity of 0.964; and achieved a higher HRD risk score in clinical BRCA-deficient breast cancer samples (p = 5.5 × 10-5, compared with BRCA-intact breast cancer samples). We also estimated the limit of detection the shallowHRD pipeline could accurately predict HRD status with a minimum sequencing depth of 0.1 ×, a tumor purity of > 20%, and an input DNA amount of 1 ng. Our study demostrates using low-pass sequencing, HRD status can be determined with high accuracy using a simple approach with greatly reduced cost.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Humanos , Feminino , Neoplasias da Mama/genética , Recombinação Homóloga/genética , Reparo do DNA , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Sequenciamento Completo do Genoma , Neoplasias Ovarianas/genética
5.
J Trace Elem Med Biol ; 77: 127140, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36812786

RESUMO

BACKGROUND: Selenium (Se) plays a beneficial role in the physiological function of humans and animals. Selenium polysaccharide, improving enzyme activity and regulating immunity, is the extraction from selenium-rich plants or mushrooms. This study aimed to evaluate the effect of selenium polysaccharide from selenium-enriched Phellinus linteus on the antioxidative ability, immunity, serum biochemistry, and production performance of laying hens. METHODS: Three hundred sixty adult laying hens were randomly assigned to 4 groups. The four groups were divided as follows: CK (control group), PS group (4.2 g/kg polysaccharide), Se group (0.5 Se mg/kg), and PSSe group (4.2 g/kg with 0.5 Se mg/kg, Selenium polysaccharide). RESULTS: After the 8 weeks, the hens were sampled and the antioxidant ability(total antioxidant (T-AOC), superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), malondialdehyde (MDA), and Nitric Oxide (NO)), immunity(Interleukin-2(IL-2), Immunoglobulin M(IgM), Immunoglobulin A(IgA), Immunoglobulin G(IgG) and interferon-gamma (IFN-γ) and secretory Immunoglobulin A(sIgA)), serum biochemistry(total protein, triglycerides, total cholesterol, glucose, glutamic-pyruvictransaminase (ALT), and aspartate transaminase (AST)) and production performance were assessed. Compared with the control group, T-AOC, SOD, CAT, GSH, IL-2, IgM, IgA, sIgA, IgG, IFN-γ, total protein, average laying rate, average egg weight, and final body were significantly increased in the PS, Se, and PSSe groups, however, the MDA and NO, triglyceride, cholesterol, glucose, AST, ALT, average daily feed consumption, and feed conversion ratio were significantly decreased in the PS, Se, and PSSe groups. The PSSe group in the immune index, antioxidant ability and serum biochemistry was improved the highest. CONCLUSION: The result suggested that selenium polysaccharide from selenium-enriched Phellinus linteus can enhance the antioxidant ability and immunity, change serum biochemistry, providing a new method for improving the production performance of laying hens.


Assuntos
Antioxidantes , Selênio , Humanos , Animais , Feminino , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Selênio/farmacologia , Selênio/metabolismo , Suplementos Nutricionais , Interleucina-2/metabolismo , Galinhas , Superóxido Dismutase/metabolismo , Imunoglobulina A Secretora/metabolismo , Imunoglobulina G , Imunoglobulina A , Ração Animal/análise , Dieta
6.
Front Oncol ; 11: 733533, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970479

RESUMO

Lung cancer is one of the most common and mortal malignancies, usually with a poor prognosis in its advanced or recurrent stages. Recently, immune checkpoint inhibitors (ICIs) immunotherapy has revolutionized the treatment of human cancers including lung adenocarcinoma (LUAD), and significantly improved patients' prognoses. However, the prognostic and predictive outcomes differ because of tumor heterogeneity. Here, we present an effective method, GDPLichi (Genes of DNA damage repair to predict LUAD immune checkpoint inhibitors response), as the signature to predict the LUAD patient's response to the ICIs. GDPLichi utilized only 7 maker genes from 8 DDR pathways to construct the predictive model and classified LUAD patients into two subgroups: low- and high-risk groups. The high-risk group was featured by worse prognosis and decreased B cells, CD8+ T cells, CD8+ central memory T cells, hematopoietic stem cells (HSC), myeloid dendritic cells (MDC), and immune scores as compared to the low-risk group. However, our research also suggests that the high-risk group was more sensitive to ICIs, which might be explained by increased TMB, neoantigen, immune checkpoint molecules, and immune suppression genes' expression, but lower TIDE score as compared to the low-risk group. This conclusion was verified in three other LUAD cohort datasets (GSE30219, GSE31210, GSE50081).

7.
Int J Biol Sci ; 15(2): 351-368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30745826

RESUMO

Exosomes, the nano-vesicles released from living cells, were the important mediator for cell-to-cell communication. In order to clarify whether the exosomes derived from obesity adipose tissue mediate insulin resistance of hepatocytes, we extract the exosomes from the adipose tissue of different mice models. Exosomes derived from ob/ob mice (Ob-exosomes), B6 mice fed with a high-fat diet (HFD-exosomes) and normal B6 mice (WT-exosomes) displayed similar size and molecular makers, but their effect on the insulin sensitivity of hepatocytes were obviously different or opposite. Abundant exosomal miRNAs in Ob-, HFD- and WT-exosomes were detected by the Next Generation Sequencing. The levels of miR-141-3p in Ob- and HFD-exosomes were significantly lower than WT-exosomes. MiR-141-3p can be effectively delivered into AML12 cells accompanied by the absorption of exosomes, but the absorption of miR-141-3p into AML12 cells could be blocked by GW4869, an inhibitor of exosome biogenesis and release. Importantly, the Ob-exosomes or miR-141-3p knockdown in WT--exosomes obviously inhibited the insulin response and glucose uptake of AML12 cells, however, the inhibitory effects on insulin function disappeared after the overexpression of miR-141-3p in Ob-exosomes or AML12 cells. The effects of miR-141-3p on insulin function could be achieved by improving the level of phosphorylation of AKT and enhancing insulin signal transduction. Therefore, the absorption of hepatocytes for exosomes released from obesity adipose tissue containing less miR-141-3p than healthy adipose tissue can significantly inhibit the insulin sensitivity and glucose uptake. Our study may certify a novel mechanism that the secretion of "harmful" exosomes from obesity adipose tissues cause insulin resistance.


Assuntos
Tecido Adiposo/metabolismo , Exossomos/metabolismo , Hepatócitos/metabolismo , Obesidade/metabolismo , Animais , Western Blotting , Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina/fisiologia , Masculino , Camundongos , MicroRNAs/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/fisiologia
8.
Environ Pollut ; 238: 336-347, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29574358

RESUMO

It has been suggested that the toxic effects of cadmium (Cd) may disrupt ovarian and uterine functions in adults. However, Cd exposure during gestation and lactation and its effects on the reproductive development in female offspring is still not clear, and the mechanisms underlying exposure toxicology remain mostly unexplored. To investigate how Cd exposure of female rats (F0) during gestation and lactation affects the reproductive development of their female offspring, we studied the steroidogenesis, folliculogenesis, puberty onset, and litter size of the first (F1) and second (F2) filial generations following F0 female rats which had been exposed to CdCl2. The mechanisms related to the early onset of puberty induced by such exposure in female offspring were explored. Maternal exposure to Cd dramatically increased the biosynthesis of steroid hormones in F1 female offspring by the activation of cAMP/PKA pathway and up-regulated expression of steroidogenesis related proteins such as StAR, CYP11A1, 3ß-HSD and CYP19A1. The high levels of steroid hormones contributed to an early puberty onset, promoted the differentiation and maturation of follicles, and led to the proliferation of endometrium that resulted in a uterus weight gain. The increased number of antral follicles eventually caused a big litter size. Despite of being free from additional Cd exposure, the levels of CYP11A1 and CYP19A1 in the ovaries of F2 female rats were also high, which resulted in a high concentration of serum progesterone. These results suggested that hormonal changes induced by exposure to Cd in utero might have a lasting effect beyond the first generation. These findings may help to better understand the origin of female sexual dysfunction in the developmental stages in general.


Assuntos
Cádmio/toxicidade , Substâncias Perigosas/toxicidade , Hormônios/sangue , Testes de Toxicidade , Animais , Aromatase/metabolismo , Aleitamento Materno , Feminino , Lactação , Exposição Materna , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/crescimento & desenvolvimento , Gravidez , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Ratos , Reprodução/efeitos dos fármacos
9.
Environ Toxicol ; 33(3): 351-360, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29214744

RESUMO

Toxic effects of maternal exposure to Cadmium (Cd) on Leydig cells of male offspring arises much concern recently, but its toxic effects on the development of Leydig cells and androgen synthesis have not been elucidated. In this study, female rats were exposed to Cd during gestation and lactation, and the development of Leydig cells in the first filial-generation (F1) male rats was investigated. The steroidogenic signaling pathway and biomarkers related to the development of Leydig cells were detected to disclose how maternal Cd-exposure caused reproductive damage. F1 male rats with maternal Cd-exposure gained a low relative weight of testis and declined levels of steroid hormones. Maternal Cd-exposure interrupted the development of Leydig cells with high expression of SRD5α and cell morphology of immature Leydig cells in adulthood, inhibited the activation of cyclic adenosine monophosphate/ protein kinase A signaling pathway and down-regulated the steroidogenic enzymes. These results would help to disclose the origin of male sexual dysfunction in the developmental stages of Leydig cells.


Assuntos
Cloreto de Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Células Intersticiais do Testículo/fisiologia , Exposição Materna/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Animais , Feminino , Lactação , Masculino , Troca Materno-Fetal , Tamanho do Órgão/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Ratos Sprague-Dawley , Reprodução , Testículo/crescimento & desenvolvimento , Testículo/patologia
10.
Appl Microbiol Biotechnol ; 99(1): 435-43, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25104033

RESUMO

This study examines the role of oxalic acid in the uptake of Cd and participation in detoxification process in Phanerochaete chrysosporium. Cd-induced oxalic acid secretion was observed with growth inhibition and enzyme inactivation (LiP and MnP) of P. chrysosporium. The peak value of oxalic acid concentration was 16.6 mM at initial Cd concentration of 100 mg L(-1). During the short-term uptake experiments, the uptake of Cd was enhanced and accelerated in the presence of oxalic acid and resulted in alleviated growth and enzyme inhibition ratios. The formation of a metal-oxalate complex therefore may provide a detoxification mechanism via effect on metal bioavailability, whereby many fungi can survive and grow in environments containing high concentrations of toxic metals. The present findings will advance the understanding of fungal resistance to metal stress, which could show promise for a more useful application of microbial technology in the treatment of metal-polluted waste.


Assuntos
Cádmio/metabolismo , Ácido Oxálico/metabolismo , Phanerochaete/efeitos dos fármacos , Phanerochaete/metabolismo , Transporte Biológico/efeitos dos fármacos , Cádmio/toxicidade , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/toxicidade , Inativação Metabólica , Viabilidade Microbiana/efeitos dos fármacos , Phanerochaete/enzimologia , Phanerochaete/crescimento & desenvolvimento
11.
J Tissue Eng Regen Med ; 9(8): 961-72, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23255530

RESUMO

A phytomolecule, icaritin, has been identified and shown to be osteopromotive for the prevention of osteoporosis and osteonecrosis. This study aimed to produce a bioactive poly (l-lactide-co-glycolide)-tricalcium phosphate (PLGA-TCP)-based porous scaffold incorporating the osteopromotive phytomolecule icaritin, using a fine spinning technology. Both the structure and the composition of icaritin-releasing PLGA-TCP-based scaffolds were evaluated by scanning electron microscopy (SEM). The porosity was quantified by both water absorption and micro-computed tomography (micro-CT). The mechanical properties were evaluated using a compression test. In vitro release of icaritin from the PLGA-TCP scaffold was quantified by high-performance liquid chromatography (HPLC). The attachment, proliferation and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) on the composite scaffold were evaluated. Both an in vitro cytotoxicity test and an in vivo test via muscular implantation were conducted to confirm the scaffold's biocompatibility. The results showed that the PLGA-TCP-icaritin composite scaffold was porous, with interconnected macro- (about 480 µm) and micropores (2-15 µm). The mechanical properties of the PLGA-TCP-icaritin scaffold were comparable with those of the pure PLGA-TCP scaffold, yet was spinning direction-dependent. Icaritin content was detected in the medium and increased with time. The PLGA-TCP-icaritin scaffold facilitated the attachment, proliferation and osteogenic differentiation of BMSCs. In vitro cytotoxicity test and in vivo intramuscular implantation showed that the composite scaffold had no toxicity with good biocompatibility. In conclusion, an osteopromotive phytomolecule, icaritin, was successfully incorporated into PLGA-TCP to form an innovative porous composite scaffold with sustained release of osteopromotive icaritin, and this scaffold had good biocompatibility and osteopromotion, suggesting its potential for orthopaedic applications.


Assuntos
Materiais Biocompatíveis/química , Substitutos Ósseos/química , Fosfatos de Cálcio/química , Flavonoides/administração & dosagem , Ácido Láctico/química , Ácido Poliglicólico/química , Engenharia Tecidual/métodos , Fosfatase Alcalina/química , Animais , Células da Medula Óssea/citologia , Osso e Ossos/patologia , Adesão Celular , Diferenciação Celular , Proliferação de Células , Cromatografia Líquida de Alta Pressão , Preparações de Ação Retardada , Flavonoides/química , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Porosidade , Coelhos , Estresse Mecânico , Propriedades de Superfície , Água/química , Microtomografia por Raio-X
12.
J Orthop Res ; 31(1): 164-72, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22807243

RESUMO

This study was designed to develop a bioactive scaffold to enhance bone defect repair in steroid-associated osteonecrosis (SAON). Icaritin, a metabolite of the herb Epimedium, has been identified as an angiogenic and osteogenic phytomolecule. Icaritin was homogenized into poly lactic-co-glycolic acid/tricalcium phosphate (PLGA/TCP) to form an icaritin-releasing porous composite scaffold (PLGA/TCP/icaritin) by fine-spinning technology. In vitro, high performance liquid chromatography was used to determine the release of icaritin during degradation of PLGA/TCP/icaritin. The osteogenic effects of PLGA/TCP/icaritin were evaluated using rat bone marrow mesenchymal stem cells (BMSCs). In vivo, the osteogenic effect of PLGA/TCP/icaritin was determined within a bone tunnel after core decompression in SAON rabbits and angiography within scaffolds was examined in rabbit muscle pouch model. In vitro study confirmed the sustainable release of icaritin from PLGA/TCP/icaritin with the bioactive scaffold promoting the proliferation and osteoblastic differentiation of rat BMSCs. In vivo study showed that PLGA/TCP/icaritin significantly promoted new bone formation within the bone defect after core decompression in SAON rabbits and enhanced neovascularization in the rabbit muscle pouch experiment. In conclusion, PLGA/TCP/icaritin is an innovative local delivery system that demonstrates sustainable release of osteogenic phytomolecule icaritin enhancing bone repair in an SAON rabbit model. The supplement of scaffold materials with bioactive phytomolecule(s) might improve treatment efficiency in challenging orthopedic conditions.


Assuntos
Fraturas do Fêmur/terapia , Flavonoides/farmacologia , Consolidação da Fratura/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fitoestrógenos/farmacologia , Alicerces Teciduais , Animais , Células da Medula Óssea/citologia , Fosfatos de Cálcio/farmacologia , Células Cultivadas , Modelos Animais de Doenças , Fraturas do Fêmur/etiologia , Fraturas do Fêmur/fisiopatologia , Consolidação da Fratura/fisiologia , Ácido Láctico/farmacologia , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Neovascularização Fisiológica/fisiologia , Osteogênese/fisiologia , Osteonecrose/complicações , Osteonecrose/fisiopatologia , Osteonecrose/terapia , Ácido Poliglicólico/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Coelhos , Ratos , Engenharia Tecidual/métodos
13.
J R Soc Interface ; 8(57): 529-39, 2011 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-20880853

RESUMO

Hydroxyapatite (HA) coatings on titanium (Ti) substrates have attracted much attention owing to the combination of good mechanical properties of Ti and superior biocompatibility of HA. Incorporating silver (Ag) into HA coatings is an effective method to impart the coatings with antibacterial properties. However, the uniform distribution of Ag is still a challenge and Ag particles in the coatings are easy to agglomerate, which in turn affects the applications of the coatings. In this study, we employed pulsed electrochemical deposition to co-deposit HA and Ag simultaneously, which realized the uniform distribution of Ag particles in the coatings. This method was based on the use of a well-designed electrolyte containing Ag ions, calcium ions and l-cysteine, in which cysteine acted as the coordination agent to stabilize Ag ions. The antibacterial and cell culture tests were used to evaluate the antibacterial properties and biocompatibility of HA/Ag composite coatings, respectively. The results indicated the as-prepared coatings had good antibacterial properties and biocompatibility. However, an appropriate silver content should be chosen to balance the biocompatibility and antibacterial properties. Heat treatments promoted the adhesive strength and enhanced the biocompatibility without sacrificing the antibacterial properties of the HA/Ag coatings. In summary, this study provided an alternative method to prepare bioactive surfaces with bactericidal ability for biomedical devices.


Assuntos
Durapatita/química , Técnicas Eletroquímicas , Nanoestruturas/química , Prata/química , Titânio/química , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Nanoestruturas/ultraestrutura , Prata/farmacologia , Staphylococcus/efeitos dos fármacos , Propriedades de Superfície
14.
J Biomed Mater Res A ; 89(2): 326-35, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18431794

RESUMO

Osteoinductivity of hydroxyapatite (HA) was investigated using uncommitted pluripotent mouse stem cells, C3H10T1/2 in an in vitro differentiation assay. For comparative analysis, the cells were cultured on substrates made of osteoinductive HA, with biocompatible titanium and plastics as the negative control. HA exhibited the ability to induce expression of osteo-specific genes in C3H10T1/2, including alkaline phosphatase (ALP), type I collagen, and osteocalcin; compared with its insignificant up-regulation of the same genes in osteoblast-like cells, Saos-2. HA osteoinductivity exhibited in C3H10T1/2 was comparable to that of a bone morphogenetic protein (BMP) with reference to the up-regulation of osteo-specific genes except the core binding factor 1 (Cbfa1, Runx). This result implies a difference in osteogenic induction pathway initiated by HA and BMP. Using this mesenchymal stem cells (MSC) culture assay, osteoinductivity was also demonstrated to be present in the conditioned medium derived from MSC cultured on HA substrates. This conditioned medium exhibited excellent ability to up-regulate ALP in the absence of HA and BMP. The results suggest that the HA can interact with the cells and generate potent inductive substance released into the medium. Such substance in turn is able to induce uncommitted cells to differentiate into the osteolineage.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Durapatita/farmacologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Animais , Proteínas Morfogenéticas Ósseas/farmacologia , Cálcio/metabolismo , Meios de Cultura , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Íons , Células-Tronco Mesenquimais/enzimologia , Camundongos , Especificidade de Órgãos/efeitos dos fármacos , Fosfatos/metabolismo , Soro
15.
Clin Biomech (Bristol, Avon) ; 21(4): 387-94, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16427166

RESUMO

BACKGROUND: This study evaluated the low intensity pulsed ultrasound enhancement on matrix hardness of the healing tissues at the bone-tendon junction. METHODS: Sixteen 18 week-old mature female rabbits were used. An established transverse partial patellectomy was performed at the distal one-third of the patella. Animals were then divided according to their body weight into ultrasound group (n = 8) with daily treatment of low intensity pulsed ultrasound and control group (n = 8) without ultrasound treatment. Animals were euthanized at week 8 and 16 postoperatively to evaluate the radiographic new bone formation and the Vickers hardness of the matrix of the healing tissues at the bone-tendon junction. FINDINGS: (1) Comparing with the control group, the anterior-posterior area of the new bone in the ultrasound treated group was found on average to be 3.0 and 3.1 times greater at week 8 and 16, respectively (P < 0.01). (2) The Vickers hardness of the new bone in ultrasound group was 11.3% (P < 0.05) significantly lower at week 8 but 20.0% (P < 0.05) significantly higher at week 16 as compared with that of the control group. (3) The Vickers hardness of the newly regenerated fibrocartilage zone, healing tendon, and cartilaginous metaplasia in ultrasound group was found higher than the control group at both week 8 and 16, but the difference was significant at week 16 only, being 44.1% (P < 0.05), 20.1% (P < 0.01), and 46.4% (P < 0.01) higher, respectively. INTERPRETATION: The preliminary findings suggested for the first time that low intensity pulsed ultrasound treatment resulted in the enhancement of the matrix hardness in new bone, fibrocartilage, cartilaginous metaplasia, and healing tendon at the healing bone-tendon junction. These findings can be extrapolated into clinical practice, i.e. the more rapid healing induced by low intensity pulsed ultrasound, the earlier mobilization of the affected joint. The beneficial effects on prevention of the musculoskeletal deterioration resulting from the prolonged immobilization would be therefore expected.


Assuntos
Matriz Óssea/fisiopatologia , Consolidação da Fratura/fisiologia , Patela/lesões , Patela/efeitos da radiação , Traumatismos dos Tendões/fisiopatologia , Traumatismos dos Tendões/terapia , Terapia por Ultrassom/métodos , Animais , Matriz Óssea/efeitos da radiação , Modelos Animais de Doenças , Matriz Extracelular/efeitos da radiação , Feminino , Consolidação da Fratura/efeitos da radiação , Dureza/efeitos da radiação , Coelhos , Doses de Radiação , Resultado do Tratamento
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