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1.
Curr Med Imaging ; 20: 1-11, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389371

RESUMO

BACKGROUND: The prediction power of MRI radiomics for microvascular invasion (MVI) in patients with hepatocellular carcinoma (HCC) remains uncertain. OBJECTIVE: To investigate the prediction performance of MRI radiomics for MVI in HCC. METHODS: Original studies focusing on preoperative prediction performance of MRI radiomics for MVI in HCC, were systematically searched from databases of PubMed, Embase, Web of Science and Cochrane Library. Radiomics quality score (RQS) and risk of bias of involved studies were evaluated. Meta-analysis was carried out to demonstrate the value of MRI radiomics for MVI prediction in HCC. Influencing factors of the prediction performance of MRI radiomics were identified by subgroup analyses. RESULTS: 13 studies classified as type 2a or above according to the Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis statement were eligible for this systematic review and meta-analysis. The studies achieved an average RQS of 14 (ranging from 11 to 17), accounting for 38.9% of the total points. MRI radiomics achieved a pooled sensitivity of 0.82 (95%CI: 0.78 - 0.86), specificity of 0.79 (95%CI: 0.76 - 0.83) and area under the summary receiver operator characteristic curve (AUC) of 0.88 (95%CI: 0.84 - 0.91) to predict MVI in HCC. Radiomics models combined with clinical features achieved superior performances compared to models without the combination (AUC: 0.90 vs 0.85, P < 0.05). CONCLUSION: MRI radiomics has the potential for preoperative prediction of MVI in HCC. Further studies with high methodological quality should be designed to improve the reliability and reproducibility of the radiomics models for clinical application. The systematic review and meta-analysis was registered prospectively in the International Prospective Register of Systematic Reviews (No. CRD42022333822).


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Radiômica , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética
2.
Clinics (Sao Paulo) ; 78: 100264, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37562218

RESUMO

The power of computed tomography (CT) radiomics for preoperative prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) demonstrated in current research is variable. This systematic review and meta-analysis aim to evaluate the value of CT radiomics for MVI prediction in HCC, and to investigate the methodologic quality in the workflow of radiomics research. Databases of PubMed, Embase, Web of Science, and Cochrane Library were systematically searched. The methodologic quality of included studies was assessed. Validation data from studies with Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) statement type 2a or above were extracted for meta-analysis. Eleven studies were included, among which nine were eligible for meta-analysis. Radiomics quality scores of the enrolled eleven studies varied from 6 to 17, accounting for 16.7%-47.2% of the total points, with an average score of 14. Pooled sensitivity, specificity, and Area Under the summary receiver operator Characteristic Curve (AUC) were 0.82 (95% CI 0.77-0.86), 0.79 (95% CI 0.75-0.83), and 0.87 (95% CI 0.84-0.91) for the predictive performance of CT radiomics, respectively. Meta-regression and subgroup analyses showed radiomics model based on 3D tumor segmentation, and deep learning model achieved superior performances compared to 2D segmentation and non-deep learning model, respectively (AUC: 0.93 vs. 0.83, and 0.97 vs. 0.83, respectively). This study proves that CT radiomics could predict MVI in HCC. The heterogeneity of the included studies precludes a definition of the role of CT radiomics in predicting MVI, but methodology warrants uniformization in the radiology community regarding radiomics in HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Bases de Dados Factuais , Estudos Retrospectivos
3.
Quant Imaging Med Surg ; 13(7): 4504-4513, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37456311

RESUMO

Background: Renal ectopic lipid deposition (ELD) plays a significant role in the development of diabetic nephropathy (DN). This study aimed to use the magnetic resonance (MR) mDixon-Quant technique to evaluate renal ELD and its association with the expression of sterol regulatory element binding protein 1 (SREBP-1) and peroxisome proliferator-activated receptor alpha (PPARα) in renal tissue. Methods: Seventy male Sprague-Dawley (SD) rats were randomly divided into experimental (n=50) and control groups (n=20). A high-fat diet combined with low-dose streptozotocin (STZ) was administered to the experimental group to establish a type 2 diabetes mellitus (T2DM) model. The rats received renal mDixon-Quant scans and blood lipid and histopathological examinations in batches after the T2DM model was established. According to the histopathological findings, the included rats were stratified into control and early DN groups. Renal fat fraction (FF), blood lipid level, the ratio of the integrated optical density of intracellular lipid droplets and the total area of all the cells (IOD/TAC), and the expression of SREBP-1 and PPARɑ in renal tissue were analyzed. Results: Compared to the controls, renal FF, IOD/TAC, the expression of SREBP-1 in renal tissue, and serum total cholesterol (TC), triglyceride (TG) and low-density lipoprotein (LDL) levels were higher in the early DN group, while the expression of PPARɑ in renal tissue and the high-density lipoprotein (HDL) level were lower (all P values <0.001). Renal FF gradually increased with the progression of disease [r=0.810 (95% CI: 0.675-0.928), P<0.001]. Positive correlations between renal FF and each of the following: TC, TG, LDL, IOD/TAC, and the expression of SREBP-1 [r=0.479 (95% CI: 0.353-0.640, P=0.012), 0.576 (95% CI: 0.283-0.842, P=0.002), 0.441 (95% CI: 0.305-0.606, P=0.021), 0.911 (95% CI: 0.809-0.964, P<0.001) and 0.800 (95% CI: 0.640-0.910, P<0.001), respectively] and negative correlations between renal FF and each of the following: HDL and the expression of PPARɑ [r=-0.611 (95% CI: -0.809 to -0.469, P=0.001) and -0.748 (95% CI: -0.886 to -0.585, P<0.001), respectively] were found. Conclusions: Renal lipid deposition evaluated by the MR mDixon-Quant technique is associated with the blood lipid level, histological fat quantification, and the expression of SREBP-1 and PPARɑ in renal tissue. The renal FF value might serve as a biomarker for better understanding of renal lipid metabolism in early-stage DN.

4.
Front Oncol ; 13: 1206659, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404753

RESUMO

Objectives: To investigate the value of apparent diffusion coefficient (ADC) histogram analysis based on whole tumor volume for the preoperative prediction of lymphovascular space invasion (LVSI) in patients with stage IB-IIA cervical cancer. Methods: Fifty consecutive patients with stage IB-IIA cervical cancer were stratified into LVSI-positive (n = 24) and LVSI-negative (n = 26) groups according to the postoperative pathology. All patients underwent pelvic 3.0T diffusion-weighted imaging with b-values of 50 and 800 s/mm2 preoperatively. Whole-tumor ADC histogram analysis was performed. Differences in the clinical characteristics, conventional magnetic resonance imaging (MRI) features, and ADC histogram parameters between the two groups were analyzed. Receiver operating characteristic (ROC) analysis was used to evaluate the diagnostic performance of ADC histogram parameters in predicting LVSI. Results: ADCmax, ADCrange, ADC90, ADC95, and ADC99 were significantly lower in the LVSI-positive group than in the LVSI-negative group (all P-values < 0.05), whereas no significant differences were reported for the remaining ADC parameters, clinical characteristics, and conventional MRI features between the groups (all P-values > 0.05). For predicting LVSI in stage IB-IIA cervical cancer, a cutoff ADCmax of 1.75×10-3 mm2/s achieved the largest area under ROC curve (Az) of 0.750, followed by a cutoff ADCrange of 1.36×10-3 mm2/s and ADC99 of 1.75×10-3 mm2/s (Az = 0.748 and 0.729, respectively), and the cutoff ADC90 and ADC95 achieved an Az of <0.70. Conclusion: Whole-tumor ADC histogram analysis has potential value for preoperative prediction of LVSI in patients with stage IB-IIA cervical cancer. ADCmax, ADCrange, and ADC99 are promising prediction parameters.

5.
Clinics ; 78: 100264, 2023. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1506008

RESUMO

Abstract The power of computed tomography (CT) radiomics for preoperative prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC) demonstrated in current research is variable. This systematic review and meta-analysis aim to evaluate the value of CT radiomics for MVI prediction in HCC, and to investigate the methodologic quality in the workflow of radiomics research. Databases of PubMed, Embase, Web of Science, and Cochrane Library were systematically searched. The methodologic quality of included studies was assessed. Validation data from studies with Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) statement type 2a or above were extracted for meta-analysis. Eleven studies were included, among which nine were eligible for meta-analysis. Radiomics quality scores of the enrolled eleven studies varied from 6 to 17, accounting for 16.7%-47.2% of the total points, with an average score of 14. Pooled sensitivity, specificity, and Area Under the summary receiver operator Characteristic Curve (AUC) were 0.82 (95% CI 0.77-0.86), 0.79 (95% CI 0.75-0.83), and 0.87 (95% CI 0.84-0.91) for the predictive performance of CT radiomics, respectively. Meta-regression and subgroup analyses showed radiomics model based on 3D tumor segmentation, and deep learning model achieved superior performances compared to 2D segmentation and non-deep learning model, respectively (AUC: 0.93 vs. 0.83, and 0.97 vs. 0.83, respectively). This study proves that CT radiomics could predict MVI in HCC. The heterogeneity of the included studies precludes a definition of the role of CT radiomics in predicting MVI, but methodology warrants uniformization in the radiology community regarding radiomics in HCC.

6.
Mol Reprod Dev ; 87(2): 223-230, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32011766

RESUMO

Sertoli cells (SCs) are presumed to be the center of testis differentiation because they provide both structural support and biological regulation for spermatogenesis. Previous studies suggest that SCs control germ cell (GC) count and Leydig cell (LC) development in mouse testes. However, the regulatory role of SCs on peritubular myoid (PTM) cell fate in fetal testis has not been clearly reported. Here, we employed Amh-Cre; diphtheria toxin fragment A (DTA) mouse model to selectively ablate SCs from embryonic day (E) 14.5. Results found that SC ablation in the fetal stage caused the disruption of testis cords and the massive loss of GCs. Furthermore, the number of α-smooth muscle actin-labeled PTM cells was gradually decreased from E14.5 and almost lost at E18.5 in SC ablation testis. Interestingly, some Ki67 and 3ß-HSD double-positive fetal LCs could be observed in Amh-Cre; DTA testes at E16.5 and E18.5. Consistent with this phenomenon, the messenger RNA levels of Hsd3b1, Cyp11a1, Lhr, Star and the protein levels of 3ß-HSD and P450Scc were significantly elevated by SC ablation. SC ablation appears to induce ectopic proliferation of fetal LCs although the total LC number appeared reduced. Together, these findings bring us a better understanding of SCs' central role in fetal testis development.


Assuntos
Diferenciação Celular/genética , Toxina Diftérica/genética , Maturidade dos Órgãos Fetais , Integrases/genética , Fragmentos de Peptídeos/genética , Túbulos Seminíferos/embriologia , Células de Sertoli/metabolismo , Animais , Proliferação de Células/genética , Toxina Diftérica/metabolismo , Células Germinativas/metabolismo , Integrases/metabolismo , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Modelos Animais , Fragmentos de Peptídeos/metabolismo , Ratos Transgênicos , Espermatogênese
7.
Ear Nose Throat J ; 98(5): E13-E20, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30909739

RESUMO

To investigate the application of inner ear 3-dimensional fluid-attenuated inversion recovery (3D-FLAIR) magnetic resonance imaging (MRI) in patients with sudden sensorineural hearing loss (SSNHL) accompanied by inner ear hemorrhage. A total of 1252 SSNHL patients who were admitted from January 2010 to April 2018 were included in the study. The patients' clinical features, complete blood counts, coagulation profiles, audiometry data, and MRI scans were retrospectively reviewed. Twenty-four patients had high labyrinth signals on inner ear 3D-FLAIR MRI (24/1252, 1.9%) that were diagnosed as inner ear hemorrhage. One patient had endolymphatic hydrops on the contralesional side. In the 24 patients, pure tone audiometry curves revealed profound deafness (19/24) and flat moderate hearing loss (5/24); most patients had associated vertigo (23/24) and tinnitus (19/24). Patients with SSNHL (N = 24) were treated. Sixteen patients had invalid improvement, 3 patients were markedly improved, 4 patients had effective treatment, and only 1 patient was cured, for a therapeutic efficacy of 33.3% (8/24). Follow-up 3D-FLAIR MRI in patients showed absorbance of labyrinthine hemorrhage and disappearance of the high signal intensity in the inner ear within 2 weeks to 4 months. Inner ear 3D-FLAIR MRI indicate that most cases of inner ear hemorrhage are spontaneous and that high labyrinth signals are absorbed within 4 months. The site of labyrinth hemorrhage is irregular and independent of hearing loss. Conventional treatment is not very effective, and an appropriate therapy for SSNHL requires further investigation.


Assuntos
Otopatias/complicações , Orelha Interna/diagnóstico por imagem , Perda Auditiva Neurossensorial , Perda Auditiva Súbita , Hemorragia , Adulto , Audiometria de Tons Puros/métodos , China/epidemiologia , Otopatias/diagnóstico , Otopatias/fisiopatologia , Feminino , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/etiologia , Perda Auditiva Súbita/diagnóstico , Perda Auditiva Súbita/epidemiologia , Perda Auditiva Súbita/etiologia , Hemorragia/complicações , Hemorragia/diagnóstico , Hemorragia/fisiopatologia , Humanos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Zumbido/diagnóstico , Vertigem/diagnóstico
8.
J Cell Biol ; 217(11): 3901-3911, 2018 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-30097513

RESUMO

Mammalian oocytes are arrested at the prophase of the first meiotic division for months and even years, depending on species. Meiotic resumption of fully grown oocytes requires activation of M-phase-promoting factor (MPF), which is composed of Cyclin B1 and cyclin-dependent kinase 1 (CDK1). It has long been believed that Cyclin B1 synthesis/accumulation and its interaction with CDK1 is a prerequisite for MPF activation in oocytes. In this study, we revealed that oocyte meiotic resumption occurred in the absence of Cyclin B1. Ccnb1-null oocytes resumed meiosis and extruded the first polar body. Without Cyclin B1, CDK1 could be activated by up-regulated Cyclin B2. Ccnb1 and Ccnb2 double knockout permanently arrested the oocytes at the prophase of the first meiotic division. Oocyte-specific Ccnb1-null female mice were infertile due to failed MPF activity elevation and thus premature interphase-like stage entry in the second meiotic division. These results have revealed a hidden compensatory mechanism between Cyclin B1 and Cyclin B2 in regulating MPF and oocyte meiotic resumption.


Assuntos
Ciclina B1/metabolismo , Ciclina B2/metabolismo , Fator Promotor de Maturação/metabolismo , Meiose , Oócitos/metabolismo , Animais , Linhagem Celular , Ciclina B1/genética , Ciclina B2/genética , Feminino , Fator Promotor de Maturação/genética , Mesotelina , Camundongos , Camundongos Knockout , Células-Tronco Embrionárias Murinas , Oócitos/citologia
9.
Mycopathologia ; 183(3): 551-558, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29335843

RESUMO

OBJECTIVE: To improve the diagnosis and treatment of Penicilliosis marneffei without human immunodeficiency virus infection. METHODS: Analyze and review the clinical features, diagnosis and treatment of six cases of P. marneffei without human immunodeficiency virus infection at The First Affiliated Hospital of Fujian Medical University. RESULTS: Two cases were diagnosed in the ENT Department, three cases in the respiratory department and one case in the dermatological department. Penicillium marneffei infection was confirmed by sputum culture, blood culture and tissue biopsy. After definite diagnosis, one refused further treatment, and others showed significant improvement. CONCLUSION: Penicilliosis marneffei is insidious onset and easy to be escaped and misdiagnosed. To achieve early diagnosis and appropriate treatment, doubtful cases should be alerted for the diagnoses as P. marneffei.


Assuntos
Micoses/diagnóstico , Micoses/patologia , Talaromyces/isolamento & purificação , Adulto , Biópsia , Sangue/microbiologia , Humanos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Masculino , Técnicas Microbiológicas , Pessoa de Meia-Idade , Micoses/tratamento farmacológico , Micoses/microbiologia , Nasofaringe/patologia , Prognóstico , Escarro/microbiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
10.
J Assist Reprod Genet ; 35(2): 229-236, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29152689

RESUMO

PURPOSE: Spermatozoa maturation, a process required for spermatozoa to acquire progressive motility and the ability to fertilize ova, primarily occurs in the caput and corpus of the epididymis. Despite considerable efforts, the factor(s) promoting epididymal sperm maturation remains unclear. Recently, WNT signaling has been implicated in epididymal sperm maturation. METHODS: To further investigate WNT signaling function in epididymal sperm maturation, we generated Wntless conditional knockout mice (Wls cKO), Wls flox/flox ; Lcn5-Cre. RESULTS: In these mice, WNTLESS (WLS), a conserved membrane protein required for all WNT protein secretion, was specifically disrupted in the principal cells of the caput epididymidis. Immunoblot analysis showed that WLS was significantly reduced in the caput epididymidis of Wls cKO mice. In the caput epididymidis of Wls cKO mice, WNT 10A and WNT 2b, which are typically secreted by the principal cells of the caput epididymis, were not secreted. Interestingly, sperm motility analysis showed that the WLS deficiency in the caput epididymidis had no effect on sperm motility. Moreover, fertility tests showed that Wls cKO male mice had normal fertility. CONCLUSION: These results indicate that the disruption of WLS in principal cells of the caput epididymidis inhibits WNT protein secretion but has no effect on sperm motility and male fertility, suggesting that WNT signaling in the caput epididymidis may be dispensable for epididymal sperm maturation in mice.


Assuntos
Epididimo/citologia , Maturação do Esperma/fisiologia , Via de Sinalização Wnt/fisiologia , Animais , Epididimo/fisiologia , Feminino , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Masculino , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Gravidez , Taxa de Gravidez , Transporte Proteico , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Motilidade dos Espermatozoides , Proteínas Wnt/genética , Proteínas Wnt/metabolismo
11.
Cell Death Dis ; 8(10): e3142, 2017 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-29072697

RESUMO

Spermatogenesis, which involves mitosis and meiosis of male germ cells, is a highly complicated and coordinately ordered process. Cyclin B1 (CCNB1), an important regulator in cell cycle machinery, is proved essential for mouse embryonic development. However, the role of CCNB1 in mammalian spermatogenesis remains unclear. Here we tested the requirement for CCNB1 using conditional knockout mice lacking CCNB1 in male germ cells. We found that ablation of CCNB1 in gonocytes and spermatogonia led to mouse sterile caused by the male germ cells' depletion. Gonocyte and spermatogonia without CCNB1 is unable to proliferate normally and apoptosis increased. Moreover, CCNB1 ablation in spermatogonia may promote their differentiation by downregulating Lin28a and upregulating let-7 miRNA. However, ablation of CCNB1 in premeiotic male germ cells did not have an effect on meiosis of spermatocytes and male fertility, suggesting that CCNB1 may be dispensable for meiosis of spermatocytes. Collectively, these results indicate that CCNB1 is critically required for the proliferation of gonocytes and spermatogonia but may be redundant in meiosis of spermatocytes in mouse spermatogenesis.


Assuntos
Ciclina B1/fisiologia , Espermatogênese/fisiologia , Animais , Diferenciação Celular , Ciclina B1/deficiência , Ciclina B1/genética , Ciclina B1/metabolismo , Masculino , Camundongos , Camundongos Knockout
12.
Reproduction ; 154(5): 615-625, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28982932

RESUMO

Spermatogenesis is crucial for male fertility and is therefore tightly controlled by a variety of epigenetic regulators. However, the function of enhancer of zeste homolog 2 (EZH2) in spermatogenesis and the molecular mechanisms underlying its activity remain poorly defined. Here, we demonstrate that deleting EZH2 promoted spermatogonial differentiation and apoptosis. EZH2 is expressed in spermatogonia, spermatocytes and round and elongated spermatids from stage 9 to 11 but not in leptotene and zygotene spermatocytes. Knocking down Ezh2 in vitro using a lentivirus impaired self-renewal in spermatogonial stem cells (SSCs), and the conditional knockout of Ezh2 in spermatogonial progenitors promoted precocious spermatogonial differentiation. EZH2 functions to balance self-renewal and differentiation in spermatogonia by suppressing NEUROG3 and KIT via a direct interaction that is independent of its histone methyltransferase activity. Moreover, deleting Ezh2 enhanced the activation of CASP3 in spermatids, resulting in reduced spermatozoa production. Collectively, these data demonstrate that EZH2 plays a nonclassical role in the regulation of spermatogonial differentiation and apoptosis in murine spermatogenesis.


Assuntos
Apoptose/genética , Diferenciação Celular/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Espermatogônias/fisiologia , Animais , Células Cultivadas , Feminino , Deleção de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Camundongos Knockout , Espermatogênese/genética
13.
Int J Mol Sci ; 18(7)2017 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-28737671

RESUMO

Aneuploidy is a leading genetic cause of birth defects and lower implantation rates in humans. Most errors in chromosome number originate from oocytes. Aneuploidy in oocytes increases with advanced maternal age. Recent studies support the hypothesis that cohesion deterioration with advanced maternal age represents a leading cause of age-related aneuploidy. Cohesin generates cohesion, and is established only during the premeiotic S phase of fetal development without any replenishment throughout a female's period of fertility. Cohesion holds sister chromatids together until meiosis resumes at puberty, and then chromosome segregation requires the release of sister chromatid cohesion from chromosome arms and centromeres at anaphase I and anaphase II, respectively. The time of cohesion cleavage plays an important role in correct chromosome segregation. This review focuses specifically on the causes and effects of age-related cohesion deterioration in female meiosis.


Assuntos
Envelhecimento , Anáfase/genética , Aneuploidia , Cromátides , Segregação de Cromossomos/genética , Cromossomos Humanos , Envelhecimento/genética , Envelhecimento/metabolismo , Envelhecimento/patologia , Animais , Cromátides/genética , Cromátides/metabolismo , Cromossomos Humanos/genética , Cromossomos Humanos/metabolismo , Feminino , Humanos , Masculino , Oócitos/patologia
14.
Cell Cycle ; 16(15): 1404-1413, 2017 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-28590163

RESUMO

Mammalian oocyte chromosomes undergo 2 meiotic divisions to generate haploid gametes. The frequency of chromosome segregation errors during meiosis I increase with age. However, little attention has been paid to the question of how aging affects sister chromatid segregation during oocyte meiosis II. More importantly, how aneuploid metaphase II (MII) oocytes from aged mice evade the spindle assembly checkpoint (SAC) mechanism to complete later meiosis II to form aneuploid embryos remains unknown. Here, we report that MII oocytes from naturally aged mice exhibited substantial errors in chromosome arrangement and configuration compared with young MII oocytes. Interestingly, these errors in aged oocytes had no impact on anaphase II onset and completion as well as 2-cell formation after parthenogenetic activation. Further study found that merotelic kinetochore attachment occurred more frequently and could stabilize the kinetochore-microtubule interaction to ensure SAC inactivation and anaphase II onset in aged MII oocytes. This orientation could persist largely during anaphase II in aged oocytes, leading to severe chromosome lagging and trailing as well as delay of anaphase II completion. Therefore, merotelic kinetochore attachment in oocyte meiosis II exacerbates age-related genetic instability and is a key source of age-dependent embryo aneuploidy and dysplasia.


Assuntos
Cromátides/metabolismo , Cinetocoros/metabolismo , Oócitos/metabolismo , Envelhecimento/genética , Envelhecimento/fisiologia , Anáfase/genética , Anáfase/fisiologia , Animais , Cromátides/genética , Feminino , Imunofluorescência , Meiose/genética , Meiose/fisiologia , Camundongos , Fuso Acromático/genética , Fuso Acromático/metabolismo
15.
Cell Cycle ; 15(18): 2454-63, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27472084

RESUMO

Increases in the aneuploidy rate caused by the deterioration of cohesion with increasing maternal age have been well documented. However, the molecular mechanism for the loss of cohesion in aged oocytes remains unknown. In this study, we found that intracellular pH (pHi) was elevated in aged oocytes, which might disturb the structure of the cohesin ring to induce aneuploidy. We observed for the first time that full-grown germinal vesicle (GV) oocytes displayed an increase in pHi with advancing age in CD1 mice. Furthermore, during the in vitro oocyte maturation process, the pHi was maintained at a high level, up to ∼7.6, in 12-month-old mice. Normal pHi is necessary to maintain protein localization and function. Thus, we put forward a hypothesis that the elevated oocyte pHi might be related to the loss of cohesion and the increased aneuploidy in aged mice. Through the in vitro alkalinization treatment of young oocytes, we observed that the increased pHi caused an increase in the aneuploidy rate and the sister inter-kinetochore (iKT) distance associated with the strength of cohesion and caused a decline in the cohesin subunit SMC3 protein level. Young oocytes with elevated pHi exhibited substantially the increase in chromosome misalignment.


Assuntos
Aneuploidia , Proteínas de Ciclo Celular/metabolismo , Senescência Celular , Proteínas Cromossômicas não Histona/metabolismo , Espaço Intracelular/metabolismo , Oócitos/citologia , Oócitos/metabolismo , Envelhecimento/fisiologia , Álcalis/farmacologia , Animais , Antiportadores de Cloreto-Bicarbonato , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Cromossomos de Mamíferos/metabolismo , Vesículas Citoplasmáticas/metabolismo , Feminino , Concentração de Íons de Hidrogênio , Cinetocoros/metabolismo , Camundongos , Modelos Biológicos , Coesinas
16.
Mol Reprod Dev ; 83(7): 615-23, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27265621

RESUMO

SMAD4 is the central component of canonical signaling in the transforming growth factor beta (TGFß) superfamily. Loss of Smad4 in Sertoli cells affects the expansion of the fetal testis cords, whereas selective deletion of Smad4 in Leydig cells alone does not appreciably alter fetal or adult testis development. Loss of Smad4 in Sertoli and Leydig cells, on the other hand, leads to testicular dysgenesis, and tumor formation in mice. Within the murine testes, Smad4 is also expressed in germ cells of the seminiferous tubules. We therefore, crossed Ngn3-Cre or Stra8-Cre transgenic mice with Smad4-flox mice to generate conditional knockout animals in which Smad4 was specifically deleted in postnatal germ cells to further uncover cell type-specific requirement of Smad4. Unexpectedly, these germ-cell-knockout mice were fertile and did not exhibit any detectable abnormalities in spermatogenesis, indicating that Smad4 is not required for the production of sperm; instead, these data indicate a cell type-specific requirement of Smad4 primarily during testis development. Mol. Reprod. Dev. 83: 615-623, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Fertilidade/fisiologia , Proteína Smad4/metabolismo , Espermatogênese/fisiologia , Testículo/crescimento & desenvolvimento , Animais , Deleção de Genes , Masculino , Camundongos , Camundongos Transgênicos , Proteína Smad4/genética
17.
J Pineal Res ; 60(4): 435-47, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26993286

RESUMO

Promotion of spermatogonial stem cell (SSC) differentiation into functional sperms under in vitro conditions is a great challenge for reproductive physiologists. In this study, we observed that melatonin (10(-7) M) supplementation significantly enhanced the cultured SSCs differentiation into haploid germ cells. This was confirmed by the expression of sperm special protein, acrosin. The rate of SSCs differentiation into sperm with melatonin supplementation was 11.85 ± 0.93% which was twofold higher than that in the control. The level of testosterone, the transcriptions of luteinizing hormone receptor (LHR), and the steroidogenic acute regulatory protein (StAR) were upregulated with melatonin treatment. At the early stage of SSCs culture, melatonin suppressed the level of cAMP, while at the later stage, it promoted cAMP production. The similar pattern was observed in testosterone content. Expressions for marker genes of meiosis anaphase, Dnmt3a, and Bcl-2 were upregulated by melatonin. In contrast, Bax expression was downregulated. Importantly, the in vitro-generated sperms were functional and they were capable to fertilize oocytes. These fertilized oocytes have successfully developed to the blastula stage.


Assuntos
Antioxidantes/farmacologia , Diferenciação Celular/efeitos dos fármacos , Melatonina/farmacologia , Espermatogênese/efeitos dos fármacos , Espermatozoides/citologia , Espermatozoides/efeitos dos fármacos , Animais , Western Blotting , Células Cultivadas , Feminino , Citometria de Fluxo , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Ovinos , Injeções de Esperma Intracitoplásmicas/efeitos dos fármacos , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacos
18.
Oncotarget ; 6(35): 37012-27, 2015 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-26473289

RESUMO

Sertoli cells, the primary somatic cell in the seminiferous epithelium, provide the spermatogonial stem cell (SSC) microenvironment (niche) through physical support and the expression of paracrine factors. However, the regulatory mechanisms within the SSC niche, which is primarily controlled by Sertoli cells, remain largely unknown. GATA4 is a Sertoli cell marker, involved in genital ridge initiation, sex determination and differentiation during the embryonic stage. Here, we showed that neonatal mice with a targeted disruption of Gata4 in Sertoli cells (Gata4(flox/flox); Amh-Cre; hereafter termed Gata4 cKO) displayed a loss of the establishment and maintenance of the SSC pool and apoptosis of both gonocyte-derived differentiating spermatogonia and meiotic spermatocytes. Thus, progressive germ cell depletion and a Sertoli-cell-only syndrome were observed as early as the first wave of murine spermatogenesis. Transplantation of germ cells from postnatal day 5 (P5) Gata4 cKO mice into Kit(W/W-v) recipient seminiferous tubules restored spermatogenesis. In addition, microarray analyses of P5 Gata4 cKO mouse testes showed alterations in chemokine signaling factors, including Cxcl12, Ccl3, Cxcr4 (CXCL12 receptor), Ccr1 (CCL3 receptor), Ccl9, Xcl1 and Ccrl2. Deletion of Gata4 in Sertoli cells markedly attenuated Sertoli cell chemotaxis, which guides SSCs or prospermatogonia to the stem cell niche. Finally, we showed that GATA4 transcriptionally regulated Cxcl12 and Ccl9, and the addition of CXCL12 and CCL9 to an in vitro testis tissue culture system increased the number of PLZF+ undifferentiated spermatogonia within Gata4 cKO testes. Together, these results reveal a novel role for GATA4 in controlling the SSC niche via the transcriptional regulation of chemokine signaling shortly after birth.


Assuntos
Quimiocina CXCL12/metabolismo , Quimiocinas CC/metabolismo , Fator de Transcrição GATA4/fisiologia , Proteínas Inflamatórias de Macrófagos/metabolismo , Células de Sertoli/patologia , Espermatogônias/patologia , Nicho de Células-Tronco , Células-Tronco/patologia , Animais , Animais Recém-Nascidos , Western Blotting , Diferenciação Celular , Células Cultivadas , Quimiocina CXCL12/genética , Quimiocinas CC/genética , Quimiotaxia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Luciferases/metabolismo , Proteínas Inflamatórias de Macrófagos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células de Sertoli/metabolismo , Transdução de Sinais , Espermatogênese , Espermatogônias/metabolismo , Células-Tronco/metabolismo
19.
Artigo em Chinês | MEDLINE | ID: mdl-24016560

RESUMO

OBJECTIVE: To investigate the effect of different treatment options for the flat type of sudden hearing loss. METHODS: Prospective, multi-center clinical study was carried out using internationally used standardized clinical research method. Patients with the flat type of sudden hearing loss between 18 and 65 years old, within two weeks duration, and without any medical treatment were recruited. Treatment options were randomly selected according to the designed random table. RESULTS: From August 2007 to October 2011, 402 patients with the flat type of sudden hearing loss who met the criteria (account for 39.26% of the total number of patients) from the 33 hospitals were collected; the total effective rate was 82.59%, and no significant difference was detected between different treatments, (χ(2) = 10.95, P = 0.28). In the 402 cases, 139 were cured (34.58%); 118 were markedly improved (29.35%); 75 were effective (18.66%); 70 were invalid (17.41%). CONCLUSIONS: The therapeutic efficacy of flat type of sudden hearing loss overall is good; the treatment of improving the inner ear blood rheology and/or reducing blood fibrinogen has clinical significance; the therapeutic efficacy of using glucocorticoid systemically is good as well; there is no obvious difference between combination and single medication.


Assuntos
Perda Auditiva Súbita/terapia , Adulto , Idoso , Orelha Interna , Glucocorticoides/uso terapêutico , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
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