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1.
Hum Mol Genet ; 32(14): 2326-2334, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37133443

RESUMO

Fertilization is a fundamental process of development, and the blocking mechanisms act at the zona pellucida (ZP) and plasma membrane of the egg to prevent any additional sperm from binding, permeating and fusing after fertilization. In clinical practice, some couples undergoing recurrent IVF failures that mature oocytes had abnormal fertilization for unknown reason. Ovastacin encoded by ASTL cleave the ZP protein ZP2 and play a key role in preventing polyspermy. Here, we identified bi-allelic variants in ASTL that are mainly characterized by fertilization problems in humans. All four independent affected individuals had bi-allelic frameshift variants or predicted damaging missense variants, which follow a Mendelian recessive inheritance pattern. The frameshift variants significantly decreased the quantity of ASTL protein in vitro. And all missense variants affected the enzymatic activity that cleaves ZP2 in mouse egg in vitro. Three knock-in female mice (corresponding to three missense variants in patients) all show subfertility due to low embryo developmental potential. This work presents strong evidence that pathogenic variants in ASTL cause female infertility and provides a new genetic marker for the diagnosis of fertilization problems.


Assuntos
Infertilidade Feminina , Sêmen , Humanos , Masculino , Feminino , Camundongos , Animais , Glicoproteínas da Zona Pelúcida/genética , Glicoproteínas da Zona Pelúcida/metabolismo , Sêmen/metabolismo , Oócitos/metabolismo , Infertilidade Feminina/genética , Fertilização/genética , Metaloproteases/genética
2.
Eur Spine J ; 33(7): 2721-2733, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38809439

RESUMO

OBJECTIVE: This study was designed to investigate the clinical features, treatment modalities, and risk factors influencing neurological recovery in patients who underwent scoliosis correction with delayed postoperative neurological deficit (DPND). METHODS: Three patients with DPND were identified from 2 central databases for descriptive analysis. Furthermore, all DPND cases were retrieved from the PubMed and Embase databases. Neurological function recovery was categorized into complete and incomplete recovery groups based on the American Spinal Injury Association (ASIA) impairment scale. RESULTS: Two patients were classified as type 3, and one was classified as type 2 based on the MRI spinal cord classification. Intraoperative neurophysiological monitoring (IONM) was consistently negative throughout the corrective procedure, and intraoperative wake-up tests were normal. The average time to DPND development was 11.8 h (range, 4-18 h), and all three patients achieved complete recovery of neurological function after undergoing revision surgery. A total of 14 articles involving 31 patients were included in the literature review. The mean time to onset of DPND was found to be 25.2 h, and 85.3% (29/34) of patients experienced DPND within the first 48 h postoperatively, with the most common initial symptoms being decreased muscle strength and sensation (26 patients, 83.9%). Regarding neurological function recovery, 14 patients were able to reach ASIA grade E, while 14 patients were not able to reach ASIA grade E. Univariate analysis revealed that preoperative diagnosis (p = 0.004), operative duration (p = 0.017), intraoperative osteotomy method (p = 0.033), level of neurological deficit (p = 0.037) and deficit source (p = 0.0358) were significantly associated with neurological outcomes. Furthermore, multivariate regression analysis indicated a strong correlation between preoperative diagnosis (p = 0.003, OR, 68.633; 95% CI 4.299-1095.657) and neurological prognosis. CONCLUSION: Our findings indicate that spinal cord ischemic injury was a significant factor for patients experiencing DPND and distraction after corrective surgery may be a predisposing factor for spinal cord ischemia. Additionally, it is important to consider the possibility of DPND when limb numbness and decreased muscle strength occur within 48 h after corrective scoliosis surgery. Moreover, emergency surgical intervention is highly recommended for DPND caused by mechanical compression factors with a promising prognosis for neurological function, emphasizing the importance of taking into account preoperative orthopedic diagnoses when evaluating the potential for neurological recovery.


Assuntos
Complicações Pós-Operatórias , Recuperação de Função Fisiológica , Escoliose , Humanos , Escoliose/cirurgia , Feminino , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/epidemiologia , Masculino , Adolescente , Recuperação de Função Fisiológica/fisiologia , Prognóstico , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Doenças do Sistema Nervoso/etiologia , Criança , Adulto
3.
J Med Virol ; 95(1): e28329, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36415120

RESUMO

Numerous studies have revealed severe damage to male fertility from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, raising concerns about the potential adverse impact on reproductive function of the coronavirus disease 2019 (COVID-19) vaccine developed based on the virus. Interestingly, there are several researchers who have studied the impact of the COVID-19 mRNA vaccine since then but have come up with conflicting results. As a near-ideal candidate for mass immunization programs, inactivated SARS-CoV-2 vaccine has been widely used in many countries, particularly in less wealthy nations. However, little is known about its effect on male fertility. Here, we conducted a retrospective cohort study at a single large center for reproductive medicine in China between December 2021 and August 2022. Five hundred and nineteen fertile men with no history of laboratory-confirmed COVID-19 were included and categorized into four groups based on their vaccination status: unvaccinated group (n = 168), one-dose vaccinated group (n = 8), fully vaccinated group (n = 183), and booster group (n = 160). All of them underwent a semen analysis and most had serum sex hormone levels tested. There were no significant differences in all semen parameters and sex hormone levels between the unvaccinated group and either vaccinated group. To account for possible vaccination-to-test interval-specific changes, sub-analyses were performed for two interval groups: ≤90 and >90 days. As expected, most of the semen parameters and sex hormone levels remained unchanged between the control and vaccinated groups. However, participants in vaccinated group (≤90 days) have decreased total sperm motility and increased follicle-stimulating hormone level compared with the ones in unvaccinated group. Moreover, some trends similar to those found during COVID-19 infection and recovery were observed in our study. Fortunately, all values are within the normal range. In addition, vaccinated participants reported few adverse reactions. No special medical intervention was required, and no serious adverse reactions happened. Our study suggests that inactivated SARS-CoV-2 vaccination does not impair male fertility, possibly due to the low frequency of adverse effects. This information reassures young male population who got this vaccine worldwide, and helps guide future vaccination efforts.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Masculino , Vacinas contra COVID-19/efeitos adversos , SARS-CoV-2 , Estudos Retrospectivos , COVID-19/prevenção & controle , Motilidade dos Espermatozoides , Vacinação , Vacinação em Massa , Fertilidade
4.
J Med Virol ; 95(10): e29161, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37814968

RESUMO

Fear of possible negative effects of coronavirus disease 2019 (COVID-19) vaccine on fertility is the main reason for vaccine hesitancy among the public especially women of childbearing age. Despite the high coverage of COVID-19 vaccination in China, more scientific evidence is still needed to address their concerns and guide fertility counseling and management in the future. Herein, we performed a retrospective cohort study at a single large center for reproductive medicine in China between August 2020 and May 2023. Patients aged 20-42 years with no history of laboratory-confirmed COVID-19 were included and categorized into different groups according to their vaccination status. The serum sex hormone levels, anti-Müllerian hormone concentrations, embryo quality, and pregnancy outcomes were evaluated and compared among them. We found there were no significant differences in the concentrations of follicle-stimulating hormone, luteinizing hormone and progesterone between the unvaccinated, first-dose, second-dose, and booster vaccinated groups. However, the estradiol showed a highly significant increase in the one-dose vaccinated group compared with its levels in other groups. Among unvaccinated and either vaccinated patients, anti-Müllerian hormone levels were comparable (p = 0.139). The number of oocytes retrieved, fertilization rate and good-quality embryo rate were all similar between each group of in vitro fertilization and intracytoplasmic sperm injection. No significant differences were observed regarding other laboratory parameters. Moreover, the vaccination status of infertile couples did not exert any adverse effect on the pregnancy outcomes in all assisted reproductive technologies cycles. In short, we comprehensively evaluated the reproductive safety of inactivated severe acute respiratory syndrome coronavirus 2 vaccine and found any dose of vaccination wouldn't negatively affect female fertility parameters such as sex hormone levels and ovarian reserve. Moreover, this is the first study to complete the live birth follow-up of the cohort after receiving inactivated severe acute respiratory syndrome coronavirus 2 vaccine, further dispelling the misconception and providing reassurance for decision-making by clinicians.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Fertilidade , Feminino , Humanos , Masculino , Gravidez , Hormônio Antimülleriano , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Fertilização in vitro , Hormônios Esteroides Gonadais , Taxa de Gravidez , Estudos Retrospectivos , SARS-CoV-2 , Sêmen
5.
Phys Chem Chem Phys ; 25(18): 12668-12683, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37102198

RESUMO

Semiconductor materials with wide bandgaps are extensively employed for gas detection due to their advantages of low cost, high sensitivity, fast speed, excellent stability, and distinctive selectivity. Previous studies have reported on different kinds of semiconductor materials and their complex synthesis procedures. However, the research progress on gas-sensitive mechanisms seriously lags behind the performance improvement. The research route of the gas-sensing mechanism is not clear, resulting in an unclear development direction of novel sensitive materials. This review aims to summarize existing approaches and their progress on the interpretation of gas-sensing mechanisms in semiconductors, such as the calculations based on density functional theory, semiconductor physics, and in situ experiments. Ultimately, a reasonable route for the mechanism investigation has been proposed. It guides the development direction of novel materials and reduces the cost of screening highly selective materials. Overall, this review can provide helpful guidance concerning the gas-sensitive mechanism for scholars.

6.
BJOG ; 129(7): 1030-1038, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34882964

RESUMO

OBJECTIVE: To evaluate the effect of dehydroepiandrosterone (DHEA) pre-treatment before in vitro fertilization and embryo transfer (IVF-ET) on the live birth rate in infertile women with poor ovarian response (POR) defined according to the Bologna criteria. DESIGN: A randomized, double-blind, placebo-controlled trial. SETTING: Nine reproductive medical centers in China. POPULATION: A total of 821 participants with POR defined according to the Bologna criteria were enrolled in the study between April 2016 and December 2018. METHODS: Eligible participants were randomly assigned to receive either DHEA (n = 410) or placebo (n = 411) treatments for 4-12 weeks prior to IVF-ET, in a 1:1 ratio. MAIN OUTCOME MEASURES: Live birth rate after the first embryo transfer. RESULTS: Thirty-six (8.8%) of 410 women in the DHEA group and 37 (9.0%) of 411 women in the placebo group had a live birth, with no significant difference observed between groups (relative risk, 0.98, 95% CI, 0.63-1.51; p = 0.911). There were no significant differences in the number of retrieved oocytes, and the rates of clinical pregnancy, pregnancy loss, and cumulative live births between the two groups. CONCLUSIONS: DHEA administration prior to IVF-ET had no beneficial effect on the live birth rate relative to placebo in women with POR defined according to the Bologna criteria. TWEETABLE ABSTRACT: No benefit was found in poor ovarian responders who received DHEA administration prior to IVF.


Assuntos
Coeficiente de Natalidade , Infertilidade Feminina , Desidroepiandrosterona/uso terapêutico , Feminino , Fertilização in vitro , Humanos , Infertilidade Feminina/tratamento farmacológico , Nascido Vivo , Indução da Ovulação , Gravidez , Taxa de Gravidez
7.
Zygote ; 30(2): 217-220, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34313206

RESUMO

The finding of conjoined oocytes is a rare occurrence that accounts for only 0.3% of all human retrieved oocytes. This phenomenon is quite different from that of a traditional single oocyte emanating from one follicle, and may result in dizygotic twins and mosaicism. Given the insufficient evidence on how to approach conjoined oocytes, their fate is variable among different in vitro fertilization (IVF) centres. In this observational report, we propose a new protocol for the use of these conjoined oocytes using intracytoplasmic sperm injection (ICSI), laser-cutting technique and next-generation sequencing (NGS). The first case report demonstrates that conjoined oocytes can penetrate their shared zona pellucida (ZP) at Day 6. The second case is that of a 25-year-old female patient who underwent a successful embryo transfer cycle after removal of one oocyte in which a pair of conjoined human oocytes underwent ICSI, laser-cutting separation and NGS testing. The patient achieved pregnancy and gave birth to single healthy female originally derived from conjoined oocytes. This case provided a means through which normal pregnancy may be achieved from conjoined oocytes using laser-cutting separation techniques. The protocol described may be especially beneficial to patients with a limited number of oocytes.


Assuntos
Nascido Vivo , Oócitos , Transferência Embrionária/métodos , Feminino , Fertilização in vitro/métodos , Humanos , Lasers , Gravidez , Injeções de Esperma Intracitoplásmicas/métodos
8.
Entropy (Basel) ; 24(2)2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35205456

RESUMO

We discuss hypothesis testing and compare different theories in light of observed or experimental data as fundamental endeavors in the sciences. Issues associated with the p-value approach and null hypothesis significance testing are reviewed, and the Bayesian alternative based on the Bayes factor is introduced, along with a review of computational methods and sensitivity related to prior distributions. We demonstrate how Bayesian testing can be practically implemented in several examples, such as the t-test, two-sample comparisons, linear mixed models, and Poisson mixed models by using existing software. Caveats and potential problems associated with Bayesian testing are also discussed. We aim to inform researchers in the many fields where Bayesian testing is not in common use of a well-developed alternative to null hypothesis significance testing and to demonstrate its standard implementation.

9.
Ann Vasc Surg ; 70: 501-505, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32889163

RESUMO

BACKGROUND: The Tessari method, mixing air with the sclerosant through a 3-way tap and 2 syringes, is the most widely used method to prepare foam in foam sclerotherapy. Uniform foam with smaller bubbles has great clinical significance for venous insufficiency. We aim to modify the traditional 3-way tap to produce more uniform and stable foam with smaller bubbles. METHODS: The traditional 3-way tap was modified by inserting a porous film within its channel. EXPERIMENT DESIGN: the foam was prepared with 2 mL polidocanol plus 8 mL air plus 0.05 mL hyaluronic acid; group 1, foam prepared with 20 quick passes through a traditional 3-way tap; and groups 2-7, foam prepared using the modified 3-way tap, with 10, 12, 14, 16, 18, and 20 quick passes, respectively. The uniformity of the foam was observed under optical microscopy, and the size of bubbles quantified using the Nano measurement software. The stability of the foam was evaluated using the foam half-life time. RESULTS: The foam half-life times of groups 1-7 were 306.4, 257.4, 285.6, 304.4, 318.6, 330.2, 331.3 sec, respectively. The modified tap also produced a more uniform distribution of smaller bubbles (group 7) compared with traditional tap (group 1). CONCLUSIONS: Modified 3-way tap enhanced the stability of the sclerosant foam, with a more uniform distribution of smaller bubbles.


Assuntos
Polidocanol/química , Soluções Esclerosantes/química , Escleroterapia/instrumentação , Estabilidade de Medicamentos , Desenho de Equipamento , Meia-Vida , Teste de Materiais , Polidocanol/administração & dosagem , Soluções Esclerosantes/administração & dosagem , Fatores de Tempo
10.
Endocr J ; 67(9): 923-928, 2020 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-32418923

RESUMO

Studies suggest that there is a relationship between body mass index (BMI) and thyroid-stimulating hormone (TSH) levels. But conflicting evidence exists regarding the relationship between the two variables. Moreover, thyroid function is closely related to female fertility and has certain effects on infertility. Therefore, the present study will explore the relationship between BMI and TSH levels in patients with infertility in our center. We retrospectively analyzed relevant indicators of 2,789 in Tubal Factor Infertility patients undergoing assisted reproduction technology from January 2016 to December 2018 in our center in order to analyze the relationship between BMI and serum TSH level. The medical histories of patients were reviewed. The relationship between BMI and TSH was assessed using smooth curve fitting and multivariate regression model. The smoothing curve fitting between BMI and TSH exhibited a non-linear relationship, and the resulting curve exhibited a two-stage change and a breakpoint. By multivariate piecewise linear regression, we found that the TSH level was increased with the increase of BMI when the BMI was greater than 25.3 kg/m2 (ß 0.06, 95% CI 0.02, 0.01; p = 0.0028). In contrast, the TSH level was decreased with the increase of BMI when the BMI was less than 25.3 kg/m2 (ß -0.02, 95% CI -0.05, 0.00; p = 0.0573). Collectively, our study described a non-linear relationship between BMI and TSH level in infertile patients after adjustment of potential confounders. However, such causal relationship between BMI and TSH in infertile women still needs to be further clarified in future investigations.


Assuntos
Índice de Massa Corporal , Infertilidade Feminina/sangue , Tireotropina/sangue , Adulto , Estudos Transversais , Feminino , Humanos , Infertilidade Feminina/fisiopatologia
11.
Dermatol Surg ; 46(10): e66-e70, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31895253

RESUMO

BACKGROUND: Foam sclerotherapy is an effective treatment strategy for vascular malformations, and its sclerosing power depends on foam stability. Twenty quick passages have been widely used as an indicator of the most stable state of sclerosants, but the universality of their effectiveness has not been proven yet. OBJECTIVE: We aimed to identify simple and objective indicators of the most stable state of commonly used sclerosants and provide practitioners with suggestions to judge when foam producing is completed in sclerotherapy. MATERIALS AND METHODS: The universality of the effectiveness of 20 passages was tested by producing bleomycin foam with different passages. Further study was performed by testing modified bleomycin, polidocanol, and sodium tetradecylsulfate foam. RESULTS: The bleomycin foam became denser as passages were added, and the sound of each passage became almost silent after 40 passages. The almost silent sound can be an indicator of foam stability for most sclerosants. It has a different application range compared with 20 quick passages. CONCLUSION: We suggest that practitioners choose a different indicator depending on the foam used.


Assuntos
Bleomicina/administração & dosagem , Soluções Esclerosantes/administração & dosagem , Escleroterapia/métodos , Malformações Vasculares/terapia , Aerossóis , Bleomicina/química , Estabilidade de Medicamentos , Humanos , Soluções Esclerosantes/química , Resultado do Tratamento
12.
J Cell Mol Med ; 23(9): 5934-5948, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31298493

RESUMO

Prostate cancer (PCa) is the second leading cause of cancer-related death in males, primarily due to its metastatic potential. The present study aims to identify the expression of microRNA-539 (miR-539) in PCa and further investigate its functional relevance in PCa progression both in vitro and in vivo. Initially, microarray analysis was conducted to obtain the differentially expressed gene candidates and the regulatory miRNAs, after which the possible interaction between the two was determined. Next, ectopic expression and knock-down of the levels of miR-539 were performed in PCa cells to identify the functional role of miR-539 in PCa pathogenesis, followed by the measurement of E-cadherin, vimentin, Smad4, c-Myc, Snail1 and SLUG expression, as well as proliferation, migration and invasion of PCa cells. Finally, tumour growth was evaluated in nude mice through in vivo experiments. The results found that miR-539 was down-regulated and DLX1 was up-regulated in PCa tissues and cells. miR-539 was also found to target and negatively regulate DLX1 expression, which resulted in the inhibition of the TGF-ß/Smad4 signalling pathway. Moreover, the up-regulation of miR-539 or DLX1 gene silencing led to the inhibition of PCa cell proliferation, migration, invasion, EMT and tumour growth, accompanied by increased E-cadherin expression and decreased expression of vimentin, Smad4, c-Myc, Snail1 and SLUG. In conclusion, the overexpression of miR-539-mediated DLX1 inhibition could potentially impede EMT, proliferation, migration and invasion of PCa cells through the blockade of the TGF-ß/Smad4 signalling pathway, highlighting a potential miR-539/DLX1/TGF-ß/Smad4 regulatory axis in the treatment of PCa.


Assuntos
Proteínas de Homeodomínio/antagonistas & inibidores , MicroRNAs/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Proteína Smad4/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Fator de Crescimento Transformador beta/metabolismo , Animais , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática/genética , Masculino , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Transplante de Neoplasias , Células PC-3 , Proteínas Proto-Oncogênicas c-myc/metabolismo , Fatores de Transcrição da Família Snail/metabolismo , Transplante Heterólogo , Vimentina/metabolismo
13.
FASEB J ; 32(4): 2197-2211, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29229683

RESUMO

Tissue-engineered constructs (TECs) hold great promise for treating large bone defects. Incorporated mesenchymal stem cells (MSCs) can facilitate the vascularization of TECs. Nevertheless, the underlying mechanism remains ambiguous. Here we analyzed the roles of C-X-C chemokine receptor 2 (CXCR2) and its downstream signal pathways in MSC-induced endothelial progenitor cell (EPC) migration. Transwell assays and immunofluorescence staining were performed for cell migration analysis in vitro and in vivo, respectively. A series of signal inhibitors and short hairpin RNA was used for screening essential signaling molecules. We found that blockade of CXCR2 abolished the migration of EPCs toward MSCs as well as subsequent vascularization and bone repair in TECs. Moreover, screening results suggested that steroid receptor coactivator (Src) acted as a predominant downstream effector of CXCR2. Further molecular biologic and histomorphological experiments revealed that the action of Src required the phosphorylation of ras-related C3 botulinum toxin substrate 1 (Rac1), which was pivotal for the development of lamellipodia and filopodia. The phosphorylation and colocalization of paxillin kinase linker (PKL) and vav guanine nucleotide exchange factor 2 (Vav2) were essential for the activation of Rac1. Therefore, we demonstrated that MSCs promoted EPC migration via activating CXCR2 and its downstream Src-PKL/Vav2-Rac1 signaling pathway. These findings unveiled the molecular mechanism in the vascularization of TECs and were expected to provide novel targets for efficacy improvement.-Li, Z., Yang, A., Yin, X., Dong, S., Luo, F., Dou, C., Lan, X., Xie, Z., Hou, T., Xu, J., Xing, J. Mesenchymal stem cells promote endothelial progenitor cell migration, vascularization, and bone repair in tissue-engineered constructs via activating CXCR2-Src-PKL/Vav2-Rac1.


Assuntos
Regeneração Óssea , Movimento Celular , Células Progenitoras Endoteliais/metabolismo , Células-Tronco Mesenquimais/metabolismo , Transdução de Sinais , Engenharia Tecidual/métodos , Animais , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Células Progenitoras Endoteliais/citologia , Células Progenitoras Endoteliais/fisiologia , Proteínas Ativadoras de GTPase , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos , Neovascularização Fisiológica , Coativadores de Receptor Nuclear/metabolismo , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-vav/metabolismo , Receptores de Interleucina-8B/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo
14.
J Cell Physiol ; 233(8): 5792-5804, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29219174

RESUMO

The extracellular matrix (ECM) contains rich biological cues for cell recruitment, proliferationm, and even differentiation. The osteoinductive potential of scaffolds could be enhanced through human bone marrow mesenchymal stem cell (hBMSC) directly depositing ECM on surface of scaffolds. However, the role and mechanism of human umbilical cord mesenchymal stem cells (hUCMSC)-secreted ECM in bone formation remain unknown. We tested the osteoinductive properties of a hUCMSC-secreted ECM construct (hUCMSC-ECM) in a large femur defect of a severe combined immunodeficiency (SCID) mouse model. The hUCMSC-ECM improved the colonization of endogenous MSCs and bone regeneration, similar to the hUCMSC-seeded scaffold and superior to the scaffold substrate. Besides, the hUCMSC-ECM enhanced the promigratory molecular expressions of the homing cells, including CCR2 and TßRI. Furthermore, the hUCMSC-ECM increased the number of migrated MSCs by nearly 3.3 ± 0.1-fold, relative to the scaffold substrate. As the most abundant cytokine deposited in the hUCMSC-ECM, insulin-like growth factor binding protein 3 (IGFBP3) promoted hBMSC migration in the TßRI/II- and CCR2-dependent mechanisms. The hUCMSC-ECM integrating shRNA-mediated silencing of Igfbp3 that down-regulated IGFBP3 expression by approximately 60%, reduced the number of migrated hBMSCs by 47%. In vivo, the hUCMSC-ECM recruited 10-fold more endogenous MSCs to initiate bone formation compared to the scaffold substrate. The knock-down of Igfbp3 in the hUCMSC-ECM inhibited nearly 60% of MSC homing and bone regeneration capacity. This research demonstrates that IGFBP3 is an important MSC homing molecule and the therapeutic potential of hUCMSC-ECM in bone regeneration is enhanced by improving MSC homing in an IGFBP3-dependent mechanism.


Assuntos
Regeneração Óssea/fisiologia , Matriz Extracelular/metabolismo , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osteogênese/fisiologia , Receptor do Fator de Crescimento Transformador beta Tipo I/metabolismo , Receptores CCR2/metabolismo , Animais , Movimento Celular/fisiologia , Células Cultivadas , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Transplante de Células-Tronco Mesenquimais , Camundongos , Camundongos SCID , Interferência de RNA , RNA Interferente Pequeno/genética , Alicerces Teciduais , Cordão Umbilical/citologia
15.
Cell Physiol Biochem ; 48(1): 361-370, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30016780

RESUMO

BACKGROUND/AIMS: Tissue engineering bone transplantation with bone marrow mesenchymal stem cells (BMSCs) is an effective technology to treat massive bone loss, while molecular regulation of the bone regeneration processes remains poorly understood. Here, we aimed to assess the role of interleukin-8 (IL-8) in the recruitment of host cells by seeded BMSCs and in the bone regeneration. METHODS: A transwell assay was performed to examine the role of IL-8/CXCR1/CXCR2/PI3k/Akt on the migration potential of hBMSCs. The in vitro chondrogenic differentiation of hBMSCs was assessed by examination of 2 chondrogenic markers, Sox9 and type 2 collagen (COL2). mBMSCs were used in tissue engineered bone (TEB) with/without IL-8 implanted into bone defect area with CXCR2 or Akt inhibitors. Density and Masson staining of the regenerated bone were assessed. The chondrogenesis was assessed by expression levels of associated proteins, Sox9 and COL2, by RT-qPCR and by immunohistochemistry. RESULTS: IL-8 may trigger in vitro migration of hBMSCs via CXCR2-mediated PI3k/Akt signaling pathway. IL-8 enhances osteogenesis in the TEB-implanted bone defect in mice. IL-8 induces chondrogenic differentiation of hBMSCs via CXCR2-mediated PI3k/Akt signaling pathway in vitro and in vivo. CONCLUSIONS: IL-8 enhances therapeutic effects of MSCs on bone regeneration via CXCR2-mediated PI3k/Akt signaling pathway.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Interleucina-8/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Interleucina-8B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Células da Medula Óssea/citologia , Osso e Ossos/patologia , Osso e Ossos/fisiologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Condrogênese/efeitos dos fármacos , Colágeno Tipo II/metabolismo , Compostos Heterocíclicos com 3 Anéis/farmacologia , Humanos , Interleucina-8/genética , Interleucina-8/metabolismo , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Compostos de Fenilureia/farmacologia , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Receptores de Interleucina-8B/antagonistas & inibidores , Engenharia Tecidual
16.
Analyst ; 143(22): 5388-5394, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30295305

RESUMO

Heparin (Hep) is widely used as a major anticoagulant in surgery. Simple and sensitive methods capable of quantitative detection of Hep are desired for better regulating its clinical use. Herein, a novel nanoassembly of amino-functionalized mesoporous silica nanoparticle-gold nanoclusters (MSN-AuNCs) with remarkable emission enhancement characteristics for sensitive fluorescence detection of Hep is developed. The electrostatic interaction between the positively charged amino-functionalized MSNs and the AuNC-stabilizing surface ligands triggers the self-assembly of MSN-AuNC nanocomposites which exhibit more than 5-fold fluorescence emission enhancement. However, the presence of negatively charged Hep inhibits the emission enhancement phenomenon due to the effective wrapping of Hep on the surface of MSNs, which blocks the interaction between AuNCs and MSNs. Benefitting from the remarkable emission enhancement and the competing binding of Hep, facile and ultrasensitive detection of Hep can be realized with a detection limit as low as 2 nM. Moreover, the successful application of the proposed method for detection of Hep in human serum samples shows promise for clinical applications.


Assuntos
Ouro/química , Heparina/sangue , Nanopartículas Metálicas/química , Nanocompostos/química , Dióxido de Silício/química , Espectrometria de Fluorescência/métodos , Fluorescência , Humanos , Limite de Detecção
17.
Sensors (Basel) ; 18(10)2018 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-30340354

RESUMO

Partial discharge (PD) is not only an important symptom for monitoring the imperfections in the insulation system of a gas-insulated switchgear (GIS), but also the factor that accelerates the degradation. At present, monitoring ultra-high-frequency (UHF) signals induced by PDs is regarded as one of the most effective approaches for assessing the insulation severity and classifying the PDs. Therefore, in this paper, a deep learning-based PD classification algorithm is proposed and realized with a multi-column convolutional neural network (CNN) that incorporates UHF spectra of multiple resolutions. First, three subnetworks, as characterized by their specified designed temporal filters, frequency filters, and texture filters, are organized and then intergraded by a fully-connected neural network. Then, a long short-term memory (LSTM) network is utilized for fusing the embedded multi-sensor information. Furthermore, to alleviate the risk of overfitting, a transfer learning approach inspired by manifold learning is also present for model training. To demonstrate, 13 modes of defects considering both the defect types and their relative positions were well designed for a simulated GIS tank. A detailed analysis of the performance reveals the clear superiority of the proposed method, compared to18 typical baselines. Several advanced visualization techniques are also implemented to explore the possible qualitative interpretations of the learned features. Finally, a unified framework based on matrix projection is discussed to provide a possible explanation for the effectiveness of the architecture.

18.
J BUON ; 23(6): 1840-1845, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30610811

RESUMO

PURPOSE: Gliomas are destructive malignancies affecting mainly the central nervous system. Gliomas constitute around 50% of all the central nervous system tumors. The purpose of this study was to examine the anticancer activity of cycloartenol against the glioma U87 cells and to investigate the underlying mechanisms. METHODS: MTT and colony formation assay were used to determine the proliferation rate. Acridine orange/ethidium bromide (AO/EB) and annexin V/propidium iodide (PI) were used to determine apoptosis and cell cycle analysis was carried out by western blotting. Cell migration was checked by cell migration assay and immunoblotting was used for checking protein expressions. RESULTS: The results revealed that cycloartenol inhibited the proliferation and the colony formation potential of the glioma U87 cells in a concentration-dependent manner. The antiproliferative effects were found to be due to induction of Sub-G1 cell cycle arrest and triggering of apoptosis. These effects were found to be dose-dependent. Cycloartenol also caused significant alteration in the expression of Bax and Bcl-2. Furthermore, cycloartenol inhibited the migration of glioma cells and suppressed the phosphorylation of the p38 MAP kinase. CONCLUSION: These findings indicate that cycloartenol may prove beneficial in the treatment of glioma and warrants further investigation.


Assuntos
Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioma/patologia , Fitosteróis/farmacologia , Triterpenos/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Glioma/tratamento farmacológico , Glioma/metabolismo , Humanos , Fosforilação , Células Tumorais Cultivadas
19.
Cell Mol Neurobiol ; 37(2): 195-210, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26971344

RESUMO

microRNA, a family of small non-coding RNA, plays significant roles in regulating gene expression, mainly via binding to the 3'-untranslated region of target genes. Although the role of miRNA in regulating neuroinflammation via the innate immune pathway has been studied, its role in the production of inflammatory mediators during microglial activation is poorly understood. In this study, we investigated the effect of miR-27a on lipopolysaccharide (LPS)-induced microglial inflammation. miR-27a expression was found to be rapidly decreased in microglia by real-time polymerase chain reaction (real-time PCR) after LPS stimulation. Over-expression of miR-27a significantly decreased the production of inflammatory cytokines, such as interleukin-6 (IL-6), interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α), and nitric oxide (NO), whereas knockdown of miR-27a increased the expression of these inflammatory factors. We also demonstrated by loss- and gain-of-function studies that miR-27a directly suppressed the expression of toll-like receptor 4 (TLR4) and interleukin-1 receptor-associated kinase 4 (IRAK4)-a pivotal adaptor kinase in the TLR4/MyD88 signaling pathway-by directly binding their 3'-UTRs: knocking down TLR4 or IRAK4 in microglia significantly decreased TLR4 or IRAK4 expression and inhibited the downstream production of inflammatory mediators. Moreover, the inflammatory cytokines IL-6 and IL-1ß were regulated by IRAK4, whereas TNF-α and NO were more dependent on TLR4 activation. Thus, miR-27a might regulate the LPS-induced production of inflammatory cytokines in microglia independently of TLR4 and IRAK4. Taken together, our results suggest that miR-27a is associated with microglial activation and the inflammatory response.


Assuntos
Marcação de Genes/métodos , Lipopolissacarídeos/toxicidade , MicroRNAs/fisiologia , Microglia/metabolismo , Proteínas Serina-Treonina Quinases/biossíntese , Receptor 4 Toll-Like/biossíntese , Animais , Animais Recém-Nascidos , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Mediadores da Inflamação/antagonistas & inibidores , Mediadores da Inflamação/metabolismo , Microglia/efeitos dos fármacos , Mimetismo Molecular/fisiologia , Proteínas Serina-Treonina Quinases/genética , Ratos , Ratos Sprague-Dawley , Receptor 4 Toll-Like/genética
20.
Mikrochim Acta ; 185(1): 63, 2017 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-29594655

RESUMO

The authors describe a fluorescent "turn-on" assay for detection of uric acid (UA) based on the use of graphene quantum dots coated with a shell of silver (GQD@Ag). The fluorescence of the GQDs is quenched by the silver shell. However, if the silver shell was removed via etching with H2O2 (which is produced by uricase catalyzed oxidation of UA), the fluorescence of the GQDs is restored. The resulting increase in fluorescence at 466 nm depends directly on the concentration of H2O2, which, in turn, depends on the concentration of UA. The method allows UA to be quantitated with a 2 µM detection limit. It was applied to the analysis of human urine samples and exhibited satisfactory results. The method is cost-effective, sensitive and selective for UA. In our perception, it provides a useful tool in clinical analysis and may be extended to other assays based on the use of oxidases. Graphical abstract Schematic of the reduction of Ag(I) and the growth of a silver shell on the surface of graphene quantum dots (GQDs) to form a GQD@Ag nanocomposite whose fluorescence is quenched. Uricase catalyzes the oxidation of uric acid (UA) to produce allantoin and H2O2 which etches the silver shell. This results in the release of GQDs and increased fluorescence, allowing quantitative analysis of UA.

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