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1.
Zygote ; 30(1): 72-79, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34034847

RESUMO

To determine the effects of sperm DNA fragmentation (SDF) on embryo morphokinetic parameters, cleavage patterns and embryo quality, this retrospective study analyzed 151 intracytoplasmic sperm injection (ICSI) cycles (1152 embryos collected) between November 2016 and June 2019. SDF was assessed using sperm chromatin dispersion. The cycles were divided into two groups based on the SDF rate: SDF < 15% (n = 114) and SDF ≥ 15% (n = 37). The embryo morphokinetic parameters, cleavage patterns, and embryo quality were compared between the two groups. The morphokinetic parameters tPNf, t2, t3, t4, t5, t6, and t8 were achieved significantly earlier in the SDF < 15% group compared with in the SDF ≥ 15% group. The fertilization and 2PN rates seemed to be significantly higher in the SDF < 15% group compared with in the SDF ≥ 15% group, while the abnormal cleavage rates were similar. However, a significantly higher rate of chaotic cleavage (CC) was observed in the SDF ≥ 15% group. The D3 high-quality embryo and available embryo rates were similar between the two groups. The blastocyst formation, high-quality blastocyst, and available blastocyst rates in the SDF < 15% group were significantly higher than those in the SDF ≥ 15% group. With an increase in SDF level, the chemical pregnancy, clinical pregnancy and implantation rates tended to decrease, while the miscarriage rate increased. This study demonstrated that SDF ≥ 15% reduces the fertilization rate of ICSI cycles and affects certain morphokinetic parameters. A higher SDF level can also induce a higher rate of CC, with subsequent decreases in the blastocyst formation rate and blastocyst quality.


Assuntos
Cromatina , Injeções de Esperma Intracitoplásmicas , Blastocisto , Fragmentação do DNA , Feminino , Fertilização , Fertilização in vitro , Humanos , Masculino , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Espermatozoides
2.
Zhonghua Nan Ke Xue ; 25(3): 223-230, 2019 Mar.
Artigo em Zh | MEDLINE | ID: mdl-32216240

RESUMO

OBJECTIVE: To investigate the incidence of chromosome polymorphisms and their influence on semen quality and sperm DNA integrity in male patients receiving in vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). METHODS: We retrospectively analyzed the chromosomal karyotypes and the types and incidence rate of chromosome polymorphisms in 2 370 male patients undergoing IVF/ICSI between June 2016 and June 2018. We classified the patients into groups A (with variation in the secondary constriction region in the autosomal long arm), B (with variation in the short arm of the D/G group chromosomes), C (with interbrachial inversion of chromosome 9) and D (with Y chromosome polymorphisms), and compared the semen parameters and sperm DNA fragmentation indexes (DFI) between the patients with chromosome polymorphisms and those with normal chromosomes. RESULTS: Totally, 154 (6.50%) of the patients undergoing IVF/ICSI were found with chromosome polymorphisms, including 34 cases of secondary constriction variation in the long arm of the autosome (1.43% ï¼»34/2 370ï¼½, 22.08% ï¼»34/154ï¼½), 82 cases of short arm polymorphisms of the D/G group chromosomes (3.46% ï¼»82/2 370ï¼½, 53.25% ï¼»82/154ï¼½), 26 cases of interbrachial inversion of chromosome 9 (1.10% ï¼»26/2 370ï¼½, 16.88% ï¼»26/154ï¼½), 10 cases of Y chromosome polymorphisms (0.42% ï¼»10/2 370ï¼½, 6.50% ï¼»10/154ï¼½), and 2 cases of mixed chromosome polymorphisms (0.08% ï¼»2/2 370ï¼½, 1.42% ï¼»2/154ï¼½). The total sperm count was lower in group D than in the other polymorphism groups and the normal chromosome group, but with no statistically significant difference among the five groups (P > 0.05). The sperm progressive motility was also lower in group D than in the other five groups, with statistically significant difference from group B (27.5 ± 13.5 vs. 41.5 ± 21.1, P = 0.027), but not from the other groups (P > 0.05). No statistically significant difference was observed in the sperm DFI between the polymorphism groups and the normal chromosome group (P > 0.05), or among the polymorphism groups (P > 0.05). The proportion of normal semen was lower in group D than in the other four groups, but with no statistically significant difference among the five groups (P > 0.05). The incidence rate of asthenospermia was higher in group D than in the other four groups, but with no statistically significant difference among the five groups (P > 0.05), and so was that of oligoasthenospermia, with statistically significant difference from the normal chromosome group (30.0% vs 8.0%, P = 0.041), but not from the other polymorphism groups (P > 0.05). CONCLUSIONS: Short arm polymorphisms of the D/G group chromosomes are the most common type of chromosome polymorphisms in male patients undergoing IVF/ICSI. Polymorphisms of the Y chromosome have a negative effect on semen quality, while those of the other chromosomes do not significantly affect semen quality and sperm DNA integrity.


Assuntos
Cromossomos Humanos/genética , Fragmentação do DNA , Análise do Sêmen , Injeções de Esperma Intracitoplásmicas , DNA , Humanos , Masculino , Estudos Retrospectivos , Espermatozoides
3.
Tumour Biol ; 37(5): 5751-60, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26880583

RESUMO

Nasopharyngeal carcinoma-associated gene 6 (NGX6) is a membrane protein primarily located in the nuclear membrane and cell membrane. Several groups reported that NGX6 gene was down-regulated in nasopharyngeal carcinoma (NPC), gastric cancer, lung cancer, liver cancer, and colorectal cancer and even less in the carcinomas with metastasis. Current studies have demonstrated that NGX6 possesses various biological functions, such as regulating protein expression of related genes, involving cell signal transduction pathways, negatively controlling cell cycle progression, inhibiting angiogenesis, and increasing the sensitivity of patients to anti-cancer drugs. Some factors regulating the expression level of NGX6 gene also have been studied. The methylation of promoter of NGX6 and histone H3K9 negatively regulates its expression, similar to the function of transcription factor special protein-1 (Sp1). However, the regulatory factor early growth response gene 1 (Egr-1) is provided with positive regulation function. This review will summarize the progress of those studies on NGX6 and elucidate the potential application of NGX6 for some malignant diseases.


Assuntos
Regulação Neoplásica da Expressão Gênica , Proteínas de Membrana/fisiologia , Metástase Neoplásica/genética , Proteínas Supressoras de Tumor/fisiologia , Ciclo Celular , Metilação de DNA , Resistencia a Medicamentos Antineoplásicos/genética , Proteína 1 de Resposta de Crescimento Precoce/fisiologia , Genes Supressores de Tumor , Código das Histonas , Humanos , Proteínas de Membrana/genética , Terapia de Alvo Molecular , Neoplasias/genética , Neoplasias/patologia , Neoplasias/terapia , Neovascularização Patológica/genética , Regiões Promotoras Genéticas/genética , Transdução de Sinais , Proteínas Supressoras de Tumor/genética
4.
BMC Cancer ; 16: 218, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26975503

RESUMO

BACKGROUND: Nasopharyngeal carcinoma (NPC) is prevalent in South East Asia and Southern China particularly, despite the reported 5-year survival ratio is relative higher than other deadly cancers such as liver, renal, pancreas cancer, the lethality is characterized by high metastatic potential in the early stage and high recurrence rate after radiation treatment. MicroRNA-29c was found to be down-regulated in the serum as well as in the tissue of nasopharyngeal carcinoma tissue. METHODS: In this study, we found accidentally that the transfection of pre-miR-29c or miR-29c mimics significantly increases the expression level of miR-34c and miR-449a but doesn't affect that of miR-222 using real-time quantitative PCR in nasopharyngeal carcinoma cell lines. To explore the molecular mechanism of the regulatory role, the cells are treated with 5-Aza-2-deoxycytidine (5-Aza-CdR) treatment and the level of miR-34c and miR-449a but not miR-222 accumulated by the treatment. DNA methyltransferase 3a, 3b were down-regulated by the 5-Aza-CdR treatment with western blot and real-time quantitative PCR. RESULTS: We found that pre-miR-29c or miR-29c mimics significantly increases the expression level of miR-34c and miR-449a. We further found DNA methyltransferase 3a and 3b are the target gene of miR-29c. Restoration of miR-29c in NPC cells down-regulated DNA methyltransferase 3a, 3b, but not DNA methyltransferase T1. CONCLUSIONS: The regulation of miR-29c/DNMTs/miR-34c\449a is an important molecular axis of NPC development and targeting DNMTs or restoring of miR-29c might be a promising therapy strategy for the prevention of NPC.


Assuntos
DNA (Citosina-5-)-Metiltransferases/genética , MicroRNAs/biossíntese , Neoplasias Nasofaríngeas/genética , Apoptose/genética , Carcinoma , Linhagem Celular Tumoral , China , DNA Metiltransferase 3A , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , DNA Metiltransferase 3B
5.
J Biol Chem ; 289(52): 35731-42, 2014 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-25378401

RESUMO

Our previous study demonstrated that the NGX6b gene acts as a suppressor in the invasion and migration of nasopharyngeal carcinoma (NPC). Recently, we identified the novel isoform NGX6a, which is longer than NGX6b. In this study, we first found that NGX6a was degraded in NPC cells and that this degradation was mediated by ezrin, a linker between membrane proteins and the cytoskeleton. Specific siRNAs against ezrin increase the protein level of NGX6a in these cells. During degradation, NGX6a is not ubiquitinated but is degraded through a proteasome-dependent pathway. The distribution pattern of ezrin was negatively associated with NGX6a in an immunochemistry analysis of a nasopharyngeal carcinoma tissue microarray and fetus multiple organ tissues and Western blot analysis in nasopharyngeal and NPC cell lines, suggesting that ezrin and NGX6a are associated and are involved in the progression and invasion of NPC. By mapping the interacting binding sites, the seven-transmembrane domain of NGX6a was found to be the critical region for the degradation of NGX6a, and the amino terminus of ezrin is required for the induction of NGX6a degradation. The knockdown of ezrin or transfection of the NGX6a mutant CO, which has an EGF-like domain and a transmembrane 1 domain, resulted in no degradation, significantly reducing the ability of invasion and migration of NPC cells. This study provides a novel molecular mechanism for the low expression of NGX6a in NPC cells and an important molecular event in the process of invasion and metastasis of nasopharyngeal carcinoma cells.


Assuntos
Proteínas do Citoesqueleto/fisiologia , Proteínas de Membrana/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Carcinoma , Linhagem Celular Tumoral , Citoesqueleto/metabolismo , Humanos , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/metabolismo , Neoplasias Nasofaríngeas/patologia , Domínios e Motivos de Interação entre Proteínas , Isoformas de Proteínas/metabolismo , Proteólise , Ubiquitinação
6.
Int J Mol Sci ; 16(4): 6818-30, 2015 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-25815597

RESUMO

Nano SiO2 and MgO particles were incorporated into ß-tricalcium phosphate (ß-TCP) scaffolds to improve the mechanical and biological properties. The porous cylindrical ß-TCP scaffolds doped with 0.5 wt % SiO2, 1.0 wt % MgO, 0.5 wt % SiO2 + 1.0 wt % MgO were fabricated via selective laser sintering respectively and undoped ß-TCP scaffold was also prepared as control. The phase composition and mechanical strength of the scaffolds were evaluated. X-ray diffraction analysis indicated that the phase transformation from ß-TCP to α-TCP was inhibited after the addition of MgO. The compressive strength of scaffold was improved from 3.12 ± 0.36 MPa (ß-TCP) to 5.74 ± 0.62 MPa (ß-TCP/SiO2), 9.02 ± 0.55 MPa (ß-TCP/MgO) and 10.43 ± 0.28 MPa (ß-TCP/SiO2/MgO), respectively. The weight loss and apatite-forming ability of the scaffolds were evaluated by soaking them in simulated body fluid. The results demonstrated that both SiO2 and MgO dopings slowed down the degradation rate and improved the bioactivity of ß-TCP scaffolds. In vitro cell culture studies indicated that SiO2 and MgO dopings facilitated cell attachment and proliferation. Combined addition of SiO2 and MgO were found optimal in enhancing both the mechanical and biological properties of ß-TCP scaffold.


Assuntos
Materiais Biocompatíveis/química , Fosfatos de Cálcio/química , Óxido de Magnésio/química , Dióxido de Silício/química , Alicerces Teciduais/química , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Teste de Materiais/métodos , Microscopia Eletrônica de Varredura , Porosidade , Propriedades de Superfície , Engenharia Tecidual/métodos , Difração de Raios X
7.
Front Endocrinol (Lausanne) ; 14: 1250663, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745695

RESUMO

Background: Does short-interval second ejaculation improve sperm quality, embryo development and clinical outcomes for oligoasthenozoospermia males received intracytoplasmic sperm injection (ICSI) treatment? Methods: All enrolled male patients underwent short-interval secondary ejaculation on the day of oocyte retrieval, and 786 sibling MII oocytes from 67 cycles were equally divided into two groups based on whether the injected spermatozoons originated from the first or second ejaculation. Semen parameters, embryo development efficiency, morphokinetic parameters and clinical outcomes were compared between the two groups to assess the efficiency and clinical value of short-interval second ejaculation in ICSI cycles. Results: Short-interval second ejaculation significantly improved sperm motility, normal morphological rate, and sperm DNA integrity both before and after sperm swim-up. The high-quality blastocyst rate (24.79% versus 14.67%), available blastocyst rate (57.56% versus 48.44%), and oocyte utilization rate (52.93% versus 45.29%) were significantly higher in the second ejaculation group (P<0.05). The clinical pregnancy rate (59.09% versus 47.37%), implantation rate (42.11% versus 32.35%) and live birth rate (40.91% versus 31.58%) were higher in the second ejaculation group, but the differences were not significant (P>0.05). Time-lapse analysis showed that morphokinetic time points after the 7-cell stage were earlier in the second ejaculation group but without a significant difference (P>0.05), and abnormal embryo cleavage patterns between the two groups were not significantly different (P>0.05). Conclusions: Short-interval second ejaculation significantly improves sperm quality in oligoasthenozoospermic males, and is beneficial for blastocyst formation efficiency in ICSI cycles. This study suggested a non-invasive and simple but effective strategy for improving ICSI treatment outcomes.


Assuntos
Ejaculação , Sêmen , Feminino , Gravidez , Masculino , Humanos , Injeções de Esperma Intracitoplásmicas , Imagem com Lapso de Tempo , Motilidade dos Espermatozoides , Oócitos , Desenvolvimento Embrionário , Espermatozoides , Blastocisto
8.
Front Endocrinol (Lausanne) ; 14: 1301505, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38239979

RESUMO

Introduction: Attempts to artificially activate unfertilized oocytes at 24 h post intracytoplasmic sperm injection (ICSI) have generally resulted in poor outcomes. This study aims to explore a new strategy for early judgement and rescue activation of unfertilized oocytes at 5 h post ICSI to avoid unexpected fertilization failure (UFF) or unexpected low fertilization (ULF) in ICSI cycles. Methods: Firstly, time-lapse data from 278 ICSI cycles were retrospectively analyzed to establish an indicator for fertilization failure prediction. Secondly, 14 UFF and 20 ULF cycles were enrolled for an observational study, early rescue oocyte activation (EROA) was performed on oocytes without post-ICSI Pb2 extrusion to investigate fertilization efficiency, embryo development and clinical outcomes. Results: The average time to Pb2 extrusion post-ICSI was 3.03±1.21 h, 95.54% of oocytes had extruded Pb2 before 5 h, and the sensitivity and specificity for monitoring Pb2 extrusion at 5 h by time-lapse imaging to predict fertilization were 99.59% and 99.78%, respectively. Early rescue activation of oocytes with no Pb2 extrusion resulted in acceptable fertilization and embryo developmental outcomes, in terms of the fertilization rate (75.00, 72.99%), 2PN fertilization rate (61.36, 56.93%), good-quality embryo rate (42.59, 50.00%), blastocyst formation rate (48.28, 46.03%), good-quality blastocyst rate (34.48, 33.33%), and oocyte utilization rate (36.36, 27.74%), for both UFF and ULF cycles. The clinical pregnancy, embryo implantation, and early miscarriage rates in the rescue oocyte activation group did not significantly differ from those in the Pb2 extrusion group. Fourteen unexpected fertilization failures and 20 low fertilization ICSI cycles were rescued and resulted in clinical pregnancy rates of 40.00% (4/10) and 57.14% (8/14), respectively. Conclusions: This study demonstrates that monitoring Pb2 extrusion by time-lapse imaging can accurately predict fertilization outcomes, suggesting that early rescue oocyte activation at 5 h post ICSI is an effective strategy for avoiding unexpected fertilization failure and low fertilization in ICSI cycles.


Assuntos
Chumbo , Injeções de Esperma Intracitoplásmicas , Gravidez , Feminino , Masculino , Humanos , Injeções de Esperma Intracitoplásmicas/métodos , Estudos Retrospectivos , Sêmen , Oócitos , Fertilização/fisiologia
9.
Int J Biol Sci ; 16(11): 1941-1953, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32398961

RESUMO

Ovarian cancer (OC) is one of the malignant tumors that seriously threaten women's health, with the highest mortality rate in gynecological malignancies. The prognosis of patients with advanced OC is still poor, and the 5-year survival rate is only 20-30%. Therefore, how to improve the early diagnosis rate and therapeutic effect are urgent for patients with OC. In this research, we found that Lin28A can promote the expression of stem cell marker molecules CD133, CD44, OCT4 and Nanog. We later confirmed that Lin28A can enrich the mRNA of ras-related nuclear protein (RAN) and heat shock factor binding protein 1 (HSBP1) through RIP assay, and that Lin28A can regulate their protein expression. We also identified that RAN and HSBP1 are highly expressed in OC tissues, and that they are significantly positively correlated with the expression of Lin28A and negatively correlated with the survival prognosis of OC patients. After stable knockdown of RAN or HSBP1 in OC cells with high expression of Lin28A, the expression of the stem cell marker molecules such as OCT4, CD44 and Nanog are reduced. And after knocking down of RAN or HSBP1 in Lin28A highly expressed OC cells, the survival and invasion of OC cells and tumor size of OC xenograft in nude mice were markedly inhibited and apoptosis was increased. Our data also showed that knock down of RAN or HSBP1 can inhibit the invasion ability of OC cells by decreasing the expression of N-cadherin, Vimentin and promoting the expression of E-cadherin. Meanwhile, knockdown of RAN or HSBP1 induced cell apoptosis by inhibiting the expression of PARP. Our results indicated that Lin28A could regulate the biological behaviors in OC cells through RAN/HSBP1. These findings suggest that Lin28A/RAN/HSBP1 can be used as a marker for diagnosis and prognosis of OC patients, and RAN/HSBP1 may be a potential new target for gene therapy of OC.


Assuntos
Regulação Neoplásica da Expressão Gênica/fisiologia , Proteínas de Choque Térmico/metabolismo , Neoplasias Ovarianas/metabolismo , Proteína ran de Ligação ao GTP/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Proteínas de Choque Térmico/genética , Humanos , Camundongos , Neoplasias Experimentais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Regulação para Cima , Proteína ran de Ligação ao GTP/genética
10.
Oncogene ; 38(9): 1381-1397, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30266988

RESUMO

Ovarian cancer (OC) is the leading cause of death among women with gynecologic malignant diseases, however, the molecular mechanism of ovarian cancer is not well defined. Previous studies have found that RNA binding protein Lin28A is a key factor of maintain the pluripotency of stem cells, and it is positively correlated with the degree of several cancers (breast, prostate, liver cancer, etc). Our previous study shows that Lin28A is highly expressed in OC tissues and is involved in the regulation of OC cell biological behavior. In this study, we confirmed that high expression of Lin28A promoted the survival, invasion, metastasis, and inhibited the apoptosis of OC cells. Lin28A interacts with Rho associated coiled-coil containing protein kinase2 (ROCK2) but not ROCK1 and upregulates the expression of ROCK2 in OC cells. The binding sites of each other were identified by truncated mutations and Immuno-precipitaion (IP) assay. After knock down of ROCK2 in cells with high expression of Lin28A, the survival, invasion, metastasis was significantly inhibited and early apoptosis was increased in OC cells and OC xenograft in nude mice. Our experimental data also showed that knock down of ROCK2 but not ROCK1 inhibited the invasion by decreasing the expression of N-cadherin, Slug, ß-catenin and increasing ZO-1 expression. Simultaneously, knock down of ROCK2 induced cell apoptosis by increasing cleaved Caspase-9,cleaved Caspase-7, and cleaved Caspase-3. Taken together, Lin28A regulated the biological behaviors in OC cells through ROCK2 and the interaction of Lin28A/ROCK2 may be a new target for diagnosis and gene therapy of OC.


Assuntos
Carcinogênese/genética , Neoplasias Ovarianas/genética , Proteínas de Ligação a RNA/genética , Quinases Associadas a rho/genética , Animais , Apoptose/genética , Caspases/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Neoplasias Ovarianas/patologia , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Mol Med Rep ; 14(1): 623-9, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27222009

RESUMO

Osteogenesis is a complex multi-step process involving the differentiation of mesenchymal stem cells (MSCs) into osteoblast progenitor cells, preosteoblasts, osteoblasts and osteocytes, and the crosstalk between multiple cell types for the formation and remodeling of bone. The signaling regulatory networks during osteogenesis include various components, including growth factors, transcription factors, micro (mi)RNAs and effectors, a number of which form feedback loops controlling the balance of osteogenic differentiation by positive or negative regulation. miRNAs have been found to be important regulators of osteogenic signaling pathways in multiple aspects and multiple signaling pathways. The present review focusses on the progress in elucidating the role of miRNA in the osteogenesis signaling networks of MSCs as a substitute for bone implantation the the field of bone tissue engineering. In particular, the review classifies which miRNAs promote or suppress the osteogenic process, and summarizes which signaling pathway these miRNAs are involved in. Improvements in knowledge of the characteristics of miRNAs in osteogenesis provide an important step for their application in translational investigations of bone tissue engineering and bone disease.


Assuntos
Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , Osteogênese , Transdução de Sinais , Animais , Diferenciação Celular/genética , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Osteogênese/genética , Interferência de RNA
12.
PLoS One ; 9(1): e87755, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24498185

RESUMO

A scaffold for bone tissue engineering should have highly interconnected porous structure, appropriate mechanical and biological properties. In this work, we fabricated well-interconnected porous ß-tricalcium phosphate (ß-TCP) scaffolds via selective laser sintering (SLS). We found that the mechanical and biological properties of the scaffolds were improved by doping of zinc oxide (ZnO). Our data showed that the fracture toughness increased from 1.09 to 1.40 MPam(1/2), and the compressive strength increased from 3.01 to 17.89 MPa when the content of ZnO increased from 0 to 2.5 wt%. It is hypothesized that the increase of ZnO would lead to a reduction in grain size and an increase in density of the strut. However, the fracture toughness and compressive strength decreased with further increasing of ZnO content, which may be due to the sharp increase in grain size. The biocompatibility of the scaffolds was investigated by analyzing the adhesion and the morphology of human osteoblast-like MG-63 cells cultured on the surfaces of the scaffolds. The scaffolds exhibited better and better ability to support cell attachment and proliferation when the content of ZnO increased from 0 to 2.5 wt%. Moreover, a bone like apatite layer formed on the surfaces of the scaffolds after incubation in simulated body fluid (SBF), indicating an ability of osteoinduction and osteoconduction. In summary, interconnected porous ß-TCP scaffolds doped with ZnO were successfully fabricated and revealed good mechanical and biological properties, which may be used for bone repair and replacement potentially.


Assuntos
Substitutos Ósseos/química , Teste de Materiais , Osteoblastos/metabolismo , Engenharia Tecidual , Alicerces Teciduais/química , Óxido de Zinco/química , Linhagem Celular , Humanos , Osteoblastos/citologia
13.
Stem Cell Res Ther ; 5(2): 44, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25158069

RESUMO

Nasopharyngeal carcinoma (NPC) is the most common cancer originating in the nasopharynx, and is extremely common in southern regions of China. Although the standard combination of radiotherapy and chemotherapy has improved the efficiency in patients with NPC, relapse and early metastasis are still the common causes of mortality. Cancer stem-like cells (CSCs) or tumor initial cells are hypothesized to be involved in cancer metastasis and recurrence. Over the past decade, increasing numbers of studies have been carried out to identify CSCs from human NPC cells and tissues. The present paper will summarize the investigations on nasopharyngeal CSCs, including isolation, characteristics, and therapeutic approaches. Although there are still numerous challenges to translate basic research into clinical applications, understanding the molecular details of CSCs is essential for developing effective strategies to prevent the recurrence and metastasis of NPC.


Assuntos
Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/terapia , Células-Tronco Neoplásicas/patologia , Animais , Carcinoma , Humanos , Carcinoma Nasofaríngeo
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