Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Mais filtros

Bases de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Annu Rev Cell Dev Biol ; 33: 51-75, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28645217

RESUMO

The organization of microtubule networks is crucial for controlling chromosome segregation during cell division, for positioning and transport of different organelles, and for cell polarity and morphogenesis. The geometry of microtubule arrays strongly depends on the localization and activity of the sites where microtubules are nucleated and where their minus ends are anchored. Such sites are often clustered into structures known as microtubule-organizing centers, which include the centrosomes in animals and spindle pole bodies in fungi. In addition, other microtubules, as well as membrane compartments such as the cell nucleus, the Golgi apparatus, and the cell cortex, can nucleate, stabilize, and tether microtubule minus ends. These activities depend on microtubule-nucleating factors, such as γ-tubulin-containing complexes and their activators and receptors, and microtubule minus end-stabilizing proteins with their binding partners. Here, we provide an overview of the current knowledge on how such factors work together to control microtubule organization in different systems.


Assuntos
Centro Organizador dos Microtúbulos/metabolismo , Animais , Divisão Celular , Centrossomo/metabolismo , Complexo de Golgi/metabolismo , Humanos , Modelos Biológicos , Membrana Nuclear/metabolismo
2.
J Neurooncol ; 120(1): 33-41, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25048528

RESUMO

We have reported that basic fibroblast growth factor (bFGF) demonstrates an intimate connection with signal transducer and activator of transcription 3 (STAT3) in malignant brain tumor cells. However, its mechanisms are still unclear. In this study, we used inhibitors to block specific signaling pathways, including JAK, PI3K/Akt, and Src pathways, to explore how bFGF mediates crosstalk with STAT3 in two glioblastoma(GBM) cell lines: U251 (mutant p53) and U87 (wild-type p53). Furthermore, we explored how the bFGF/STAT3 pathway affects GBM cell apoptosis. Our results suggest that bFGF can induce the activation of STAT3 mainly through the JAK and PI3K/Akt pathways, and that siRNA-mediated knockdown of STAT3 markedly reduces the bFGF levels in U251 cells. Our results also suggest that STAT3 knockdown increases the expression of pro-apoptotic genes and decreases the expression of anti-apoptotic genes, subsequently collapsing the mitochondrial membrane potentials in vitro and impairs tumor growth in vivo.


Assuntos
Apoptose , Neoplasias Encefálicas/patologia , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Glioblastoma/patologia , RNA Interferente Pequeno/genética , Fator de Transcrição STAT3/antagonistas & inibidores , Transdução de Sinais , Animais , Western Blotting , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Proliferação de Células , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Citometria de Fluxo , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Potencial da Membrana Mitocondrial , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
3.
Zhonghua Wai Ke Za Zhi ; 52(12): 939-44, 2014 Dec.
Artigo em Zh | MEDLINE | ID: mdl-25622587

RESUMO

OBJECTIVE: To study the relationship of basic fibroblast growth factor (bFGF) and signal transducer and activator of transcription 3(STAT3) in glioma apoptosis and possible mechanisms of its interaction. METHODS: Two glioblastomamultiforme (GBM) cell lines: U87 (wild-type p53) and U251 (mutant p53) were used in this study and divided into normal control group, mock group and experiment group.Small interfering RNA-carried recombinant lentivirus, LV-bFGFsiRNA and LV-STAT3siRNA, targeting bFGF and STAT3 were constructed respectively. After 48 hours of lentivirus transfection, small molecular inhibitors were used to block specific signaling pathways, AG490 20 µmol/L blocking JAK, LY294002 20 µmol/L blocking PI3K/Akt pathways for 24 hours, 48 hours and 72 hours, respectively. Then, apoptosis, changes in apoptosis-related proteins and mitochondrial membrane potential were detected through the methods of flow cytometry, protein chip and confocal microscopy, respectively.Groups were compared using single factor analysis of variance (One-way ANOVA). RESULTS: Western blot results revealed the levels of Tyr705 and Ser727 phosphorylationin reduced in a time dependent manner by blocking JAK and PI3K/Akt pathway respectively. The results of flow cytometry showed that the apoptosis rate in normal control group, mock group, experiment group were 17.97% ± 0.24%, 18.26% ± 0.88%, 46.57% ± 1.63% in U87 cells and 15.94% ± 1.18%, 16.88% ± 0.17%, 39.34% ± 0.87% in U251 cells, respectively. There was no statistically significant change between the normal control group and the mock group (P > 0.05) , while when compared with the experiment group, both group showed statistically significant difference (F = 697.41, 729.58, both P < 0.05). The results of protein chip demonstrated that protein expression of Bad, Caspase3, Cytochrome C, p27 were higher and XIAP was lower in the experiment group compared with the normal control group and mock group. Also, confocal microscopy could detect apoptosis and mitochondrial membrane potential reduced significantly in the experimental group compared with the normal control group and the mock group. CONCLUSIONS: bFGF mainly interacts with STAT3 tyrosine site-pSTAT3(Tyr705) to influence the level of STAT3 phosphorylation;blocking bFGF/STAT3 signaling pathway can induce glioma cell apoptosis through mitochondrial pathway.


Assuntos
Apoptose , Neoplasias Encefálicas/metabolismo , Fator 2 de Crescimento de Fibroblastos/metabolismo , Glioma/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral , Citocromos c , Humanos , Mitocôndrias , Fosfatidilinositol 3-Quinases , Fosforilação , RNA Interferente Pequeno , Transfecção , Tirfostinas
4.
Artigo em Inglês | MEDLINE | ID: mdl-38386574

RESUMO

Deep brain stimulation (DBS) is establishing itself as a promising treatment for disorders of consciousness (DOC). Measuring consciousness changes is crucial in the optimization of DBS therapy for DOC patients. However, conventional measures use subjective metrics that limit the investigations of treatment-induced neural improvements. The focus of this study is to analyze the regulatory effects of DBS and explain the regulatory mechanism at the brain functional level for DOC patients. Specifically, this paper proposed a dynamic brain temporal-spectral analysis method to quantify DBS-induced brain functional variations in DOC patients. Functional near-infrared spectroscopy (fNIRS) that promised to evaluate consciousness levels was used to monitor brain variations of DOC patients. Specifically, a fNIRS-based experimental procedure with auditory stimuli was developed, and the brain activities during the procedure from thirteen DOC patients before and after the DBS treatment were recorded. Then, dynamic brain functional networks were formulated with a sliding-window correlation analysis of phase lag index. Afterwards, with respect to the temporal variations of global and regional networks, the variability of global efficiency, local efficiency, and clustering coefficient were extracted. Further, dynamic networks were converted into spectral representations by graph Fourier transform, and graph energy and diversity were formulated to assess the spectral global and regional variability. The results showed that DOC patients under DBS treatment exhibited increased global and regional functional variability that was significantly associated with consciousness improvements. Moreover, the functional variability in the right brain regions had a stronger correlation with consciousness enhancements than that in the left brain regions. Therefore, the proposed method well signifies DBS-induced brain functional variations in DOC patients, and the functional variability may serve as promising biomarkers for consciousness evaluations in DOC patients.


Assuntos
Transtornos da Consciência , Estado de Consciência , Humanos , Transtornos da Consciência/terapia , Encéfalo
5.
Clin Neurophysiol ; 147: 60-68, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36702043

RESUMO

OBJECTIVE: While deep brain stimulation (DBS) has proved effective for certain patients with disorders of consciousness (DOC), the working neural mechanism is not clear, the response varies for patients, and the assessment is inadequate. This paper aims to quantify the DBS-induced changes of consciousness in DOC patients at the neural functional level. METHODS: Ten DOC patients were included for DBS surgery. The DBS target was the right centromedian-parafascicular (CM-pf) nuclei for four patients and the bilateral CM-pf nuclei for six patients. Functional near-infrared spectroscopy (fNIRS) was taken to measure the neural activation of patients, in parallel with Coma Recovery Scale-Revised (CRS-R), before the DBS surgery and one month after. The fNIRS signals were recorded from the frontal, parietal, and occipital lobes. Functional connectivity analysis quantified the communication between brain regions, area communication strength, and global communication efficiency. Linear regression analysis was conducted between the changes of indices based on functional connectivity analysis and the changes of the CRS-R index. RESULTS: Patients with trauma (n = 4) exhibited a greater increase of CRS-R scores after DBS treatment compared with patients with hemorrhage (n = 4) and brainstem infarction (n = 2). Global communication efficiency changed consistently with the CRS-R index (slope = 57.384, p < 0.05, R2=0.483). No significant relationship was found between the changes of area communication strength of six brain lobes and the changes of the CRS-R index. CONCLUSIONS: The cause of DOC is essential for the outcome of DBS treatment, and brain communication efficiency is a promising functional marker for DOC recovery. SIGNIFICANCE: fNIRS-based functional connectivity analysis on brain network signifies changes of consciousness in DOC patients after DBS treatment.


Assuntos
Transtornos da Consciência , Estimulação Encefálica Profunda , Humanos , Encéfalo , Estado de Consciência , Coma
6.
Physiol Meas ; 44(12)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38086065

RESUMO

Objective.Deep brain stimulation (DBS) is a potential treatment that promotes the recovery of patients with disorders of consciousness (DOC). This study quantified the changes in consciousness and the neuromodulation effect of DBS on patients with DOC.Approach.Eleven patients were recruited for this study which consists of three conditions: 'Pre' (two days before DBS surgery), 'Post-On' (one month after surgery with stimulation), and 'Post-Off' (one month after surgery without stimulation). Functional near-infrared spectroscopy (fNIRS) was recorded from the frontal lobe, parietal lobe, and occipital lobe of patients during the experiment of auditory stimuli paradigm, in parallel with the coma recovery scale-revised (CRS-R) assessment. The brain hemodynamic states were defined and state transition acceleration was taken to quantify the information transmission strength of the brain network. Linear regression analysis was conducted between the changes in regional and global indicators and the changes in the CRS-R index.Main results.Significant correlation was observed between the changes in the global transition acceleration indicator and the changes in the CRS-R index (slope = 55.910,p< 0.001,R2= 0.732). For the regional indicators, similar correlations were found between the changes in the frontal lobe and parietal lobe indicators and the changes in the CRS-R index (slope = 46.612,p< 0.01,R2= 0.694; slope = 47.491,p< 0.01,R2= 0.676).Significance.Our study suggests that fNIRS-based brain hemodynamics transition analysis can signify the neuromodulation effect of DBS treatment on patients with DOC, and the transition acceleration indicator is a promising brain functional marker for DOC.


Assuntos
Encéfalo , Transtornos da Consciência , Humanos , Transtornos da Consciência/terapia , Encéfalo/diagnóstico por imagem , Estado de Consciência/fisiologia , Análise Espectral , Resultado do Tratamento
7.
Curr Biol ; 33(5): 912-925.e6, 2023 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-36720222

RESUMO

Error-free chromosome segregation in mitosis and meiosis relies on the assembly of a microtubule-based spindle that interacts with kinetochores to guide chromosomes to the cell equator before segregation in anaphase. Microtubules sprout from nucleation sites such as centrosomes, but kinetochores can also promote microtubule formation. It is unclear, however, how kinetochore-derived microtubules are generated and what their role is in chromosome segregation. Here, we show that the transient outer-kinetochore meshwork known as the fibrous corona serves as an autonomous microtubule nucleation platform. The fibrous corona is essential for the nucleation of kinetochore-derived microtubules, and when dissociated from the core kinetochore, it retains microtubule nucleation capacity. Nucleation relies on a fibrous-corona-bound pool of the LIC1 subunit of the dynein motor complex, which interacts with the γ-tubulin-tethering protein pericentrin (PCNT). PCNT is essential for microtubule nucleation from fibrous coronas, and in centrosome-depleted cells, where nearly all mitotic nucleation occurs at fibrous coronas, chromosome congression is fully dependent on PCNT. We further show that chromosomes in bovine oocytes, which naturally lack centrosomes, have highly expanded fibrous coronas that drive chromosome-derived microtubule nucleation. Preventing fibrous corona expansion in these cells impairs chromosome congression and causes spindle assembly defects. Our results show that fibrous coronas are autonomous microtubule-organizing centers that are important for spindle assembly, which may be especially relevant in acentrosomal cells such as oocytes.


Assuntos
Segregação de Cromossomos , Microtúbulos , Animais , Bovinos , Microtúbulos/metabolismo , Cinetocoros/metabolismo , Tubulina (Proteína)/metabolismo , Mitose , Fuso Acromático/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo
8.
Zhonghua Wai Ke Za Zhi ; 50(10): 928-32, 2012 Oct.
Artigo em Zh | MEDLINE | ID: mdl-23302466

RESUMO

OBJECTIVE: To preliminarily investigate the mechanism of small interfering RNA (siRNA) induced apoptosis in glioma U251 cells by silencing basic fibroblast growth factor (bFGF). METHODS: U251 cells were divided into the normal control group, the mock group and experiment group, the mock and experiment group were transfected with mock vector (Ad-null) and the recombinant adenovirus carrying bFGF-siRNA (Ad-bFGF-siRNA) respectively at a multiplicity of infection (MOI) of 100. After 72 hours, the expression of related proteins was revealed by the method of Western blot. Mitochondrial transmembrane potential (ΔΨm) was measured with flow cytometry and confocal microscopy, Groups were compared using single factor analysis of variance (One-way ANOVA). RESULTS: After U251 cells were transfected with bFGF-siRNA, the results of Western blot showed that after 72 hours of transfection the bFGF protein in the experiment group decreased obviously, meanwhile Cytochrome C, Caspase-3 and Bax showed increased expression while in the Bcl-xl and Bcl-2 proteins decreased expression. The proportion of high mitochondrial membrane potential of cells by flow cytometry, the experimental group was 74.4% ± 4.7% decreased significantly compared with the control group 92.1% ± 2.5%, the mock group 90.9% ± 1.8% (F = 28.805, P < 0.05); laser scanning confocal microscopy results showed that the red fluorescence and green fluorescence ratio of the experimental group was 0.83 ± 0.12 decreased significantly compared with 1.36 ± 0.40 of the control group and 1.32 ± 0.35 of the mock group(F = 7.920, P < 0.05). CONCLUSION: siRNA targeting bFGF induced U251 cell apoptosis may be achieved through the mitochondrial pathway.


Assuntos
Apoptose , Fator 2 de Crescimento de Fibroblastos/genética , Glioma/patologia , RNA Interferente Pequeno , Adenoviridae/genética , Linhagem Celular Tumoral , Humanos , Interferência de RNA , Transfecção
9.
Artigo em Inglês | MEDLINE | ID: mdl-36497701

RESUMO

Postsecondary institutions worldwide generally provide career development courses or similar courses to better prepare undergraduate students for healthy and quality future careers. Understanding whether these career development courses positively affect students' career-related outcomes is crucial. Utilizing survey data collected from a large research university located in the eastern part of China, we found that students who have taken at least one career course exhibited career awareness and career planning abilities that were 0.096 and 0.147 units higher, respectively, than those of students who have not taken career courses, with other variables held constant. More specifically, an additional career course was statistically significantly associated with a 0.099, 0.084, and 0.175 unit increase in students' career awareness, job search self-efficacy, and career planning ability, respectively. A student's college major and annual family income seemed to be good predictors for a student's career awareness, job search self-efficacy, and career-planning ability. Furthermore, the more career courses that a student took, the higher the career awareness, job search self-efficacy, and career planning ability that the student had. With these findings in mind, our study recommends postsecondary stakeholders to leverage such courses to help students better prepare for a healthy and quality career development.


Assuntos
Escolha da Profissão , População do Leste Asiático , Humanos , Estudantes , Inquéritos e Questionários , Autoeficácia
10.
Comput Methods Programs Biomed ; 225: 107005, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35961073

RESUMO

BACKGROUND AND OBJECTIVE: Deep brain stimulation (DBS) is an effective treatment for a number of neurological diseases, especially for the advanced stage of Parkinson's disease (PD). Objective assessment of patients' motor symptoms is crucial for accurate electrode targeting and treatment. Existing approaches suffer from subjective variability or interference with voluntary motion. This work is aimed to establish an objective assessment system to quantify bradykinesia in DBS surgery. METHODS: Based on the analysis of the requirements for intraoperative assessment, we developed a system with non-contact measurement, online movement feature extraction, and interactive data analysis and visualization. An optical sensor, Leap Motion Controller (LMC), was taken to detect hand movement in three clinical tasks. A graphic user interface was designed to process, compare and visualize the collected data and assessment results online. Quantified movement features include amplitude, frequency, velocity, their decrement and variability, etc. Technical validation of the system was performed with a motion capture system (Mocap), with respect to data-level and feature-level accuracy and reliability. Clinical validation was conducted with 20 PD patients for intraoperative assessments in DBS surgery. Treatment responses with respect to the bradykinesia movement features were analyzed. Single case analysis and group statistical analysis were performed to examine the differences between preoperative and intraoperative performance, and the correlation between the clinical ratings and the quantified assessment was analyzed. RESULTS: For the movements measured by LMC and Mocap, the average Pearson's correlation coefficient was 0.986, and the mean amplitude difference was 2.11 mm. No significant difference was found for all movement features quantified by LMC and Mocap. For the clinical tests, key movement features showed significant differences between the preoperative baseline and intraoperative performance when the brain stimulation was ON. The assessment results were significantly correlated with the MDS-UPDRS clinical ratings. CONCLUSIONS: The proposed non-contact system has established itself as an objective intraoperative assessment, analysis, and visualization tool for DBS treatment of Parkinson's disease.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Estimulação Encefálica Profunda/métodos , Humanos , Hipocinesia/terapia , Organotiofosfatos , Doença de Parkinson/diagnóstico , Doença de Parkinson/cirurgia , Reprodutibilidade dos Testes
11.
Comput Methods Programs Biomed ; 217: 106691, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35176597

RESUMO

BACKGROUND AND OBJECTIVE: Idiopathic normal pressure hydrocephalus (iNPH) is a common yet potentially reversible neurodegenerative disease, and gait disturbance is a major symptom. Lots of methodological and clinical work has been conducted on gait disturbance analysis for differential diagnosis, presurgical test, and postsurgery assessment of iNPH. Nevertheless, the verification analysis was mostly lacking for surgery response, and the temporal characteristics of ground reaction force has been rarely investigated. METHODS: In this work, we propose that plantar pressure features fundamentally signifies iNPH gait disturbance and improvement after cerebrospinal fluid (CSF) drainage by lumbar puncture tap test as well as surgical shunt implantation. The plantar pressure signals of six iNPH patients and eight healthy controls were collected, and an online database of sixteen healthy controls were used. For patients, data were collected in five periods, which are the baseline before the tap test, 8, 24, and 72 hours after the tap test, and one month after the shunt implantation surgery, respectively. Fast dynamic time warping (DTW) with an improved DTW barycenter averaging (DBA) method was proposed for temporal analysis with the measured and online plantar pressure data. An plantar-pressure variation index (PPVI) was formulated to characterize the temporal dynamic stability of walking. RESULTS: The PPVI based on temporal analysis of plantar pressure well discriminated the impaired gait (baseline, 24 and 72 hours after tap test) with the improved gait (8 hours after tap test and follow up after surgery) of the patients. Further, the PPVI was close for the improved gait of the patients and the healthy gait measured in our study as well as in the online database. CONCLUSIONS: Plantar pressure-based temporal features are promisingly effective for clinical examination and treatment of iNPH.


Assuntos
Hidrocefalia de Pressão Normal , Doenças Neurodegenerativas , Marcha/fisiologia , Humanos , Hidrocefalia de Pressão Normal/líquido cefalorraquidiano , Hidrocefalia de Pressão Normal/diagnóstico , Hidrocefalia de Pressão Normal/cirurgia , Estudos Longitudinais , Punção Espinal/métodos
12.
Comb Chem High Throughput Screen ; 25(8): 1385-1397, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34525929

RESUMO

BACKGROUND: Wilms Tumor (WT) is the most common primary renal malignancy in children. Autophagy plays dual roles in the promotion and suppression of various cancers. OBJECTIVE: The goal of our study was to develop a novel autophagy-related gene (ARG) prognostic nomogram for WT. METHODS: The Cancer Genome Atlas (TCGA) database was used. We screened the expression profiles of ARGs in 136 WT patients. The differentially expressed prognostic ARGs were evaluated by multivariate Cox regression analysis and survival analysis. A novel prognostic nomogram based on the ARGs and clinical characteristics was established using multivariate Cox regression analysis. RESULTS: First, 69 differentially expressed ARGs were identified in WT patients. Then, multivariate Cox regression analysis was used to determine 4 key prognostic ARGs (CC3CL1, ERBB2, HIF-α and CXCR4) in WT. According to their ARG expression levels, the patients were clustered into high- and low-risk groups. Next, survival analysis indicated that high-risk patients had significantly poorer overall survival than low-risk patients. The results of functional enrichment analysis suggested that autophagy may play a tumor-suppressive role in the initiation of WT. Finally, a prognostic nomogram with a Harrell's concordance index (C-index) of 0.841 was used to predict the survival probability of WT patients by integrating clinical characteristics and the 4-ARG signature. The calibration curve indicated its excellent predictive performance. CONCLUSION: In summary, the ARG signature could be a promising biomarker for monitoring the outcomes of WT. We established a novel nomogram based on the ARG signature, which accurately predicts the overall survival of WT patients.


Assuntos
Nomogramas , Tumor de Wilms , Autofagia/genética , Criança , Humanos , Prognóstico , Análise de Sobrevida , Tumor de Wilms/diagnóstico , Tumor de Wilms/genética
13.
Elife ; 112022 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35787744

RESUMO

The major microtubule-organizing center (MTOC) in animal cells, the centrosome, comprises a pair of centrioles surrounded by pericentriolar material (PCM), which nucleates and anchors microtubules. Centrosome assembly depends on PCM binding to centrioles, PCM self-association and dynein-mediated PCM transport, but the self-assembly properties of PCM components in interphase cells are poorly understood. Here, we used experiments and modeling to study centriole-independent features of interphase PCM assembly. We showed that when centrioles are lost due to PLK4 depletion or inhibition, dynein-based transport and self-clustering of PCM proteins are sufficient to form a single compact MTOC, which generates a dense radial microtubule array. Interphase self-assembly of PCM components depends on γ-tubulin, pericentrin, CDK5RAP2 and ninein, but not NEDD1, CEP152, or CEP192. Formation of a compact acentriolar MTOC is inhibited by AKAP450-dependent PCM recruitment to the Golgi or by randomly organized CAMSAP2-stabilized microtubules, which keep PCM mobile and prevent its coalescence. Linking of CAMSAP2 to a minus-end-directed motor leads to the formation of an MTOC, but MTOC compaction requires cooperation with pericentrin-containing self-clustering PCM. Our data reveal that interphase PCM contains a set of components that can self-assemble into a compact structure and organize microtubules, but PCM self-organization is sensitive to motor- and microtubule-based rearrangement.


Assuntos
Centríolos , Dineínas , Animais , Centríolos/metabolismo , Centrossomo/metabolismo , Dineínas/metabolismo , Interfase , Microtúbulos/metabolismo
14.
Int J Oncol ; 58(1): 45-56, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33367931

RESUMO

MicroRNA (miR)­mediated mRNA and multiple signaling pathway dysregulations have been extensively implicated in several cancer types, including gliomas. Although previous studies have reported that miR­301a acts as an oncogene, the underlying mechanisms of miR­301a in the initiation and progression of glioma remain unknown. The present study aimed to investigate the involvement of miR­301a­mediated signaling pathway dysregulation in glioma. The results identified that miR­301a was significantly upregulated in gliomas and was associated with a poor prognosis based on The Cancer Genome Atlas and Chinese Glioma Genome Atlas databases. Moreover, zinc and ring finger 3 (ZNRF3) exerted a critical role in the miR­301a­mediated effects on the malignant phenotype, such as by affecting proliferation and apoptosis. Mechanistically, the TOP/FOP luciferase assay, western blotting and immunofluorescence results demonstrated that miR­301a knockdown inhibited the wnt/ß­catenin signaling pathway, at least partially via ZNRF3, while ZNRF3 was a direct functional target of miR­301a, as indicated by luciferase reporter assay and western blot analysis. Furthermore, ZNRF3 could in turn repress miR­301a expression, which was dependent on the wnt pathway. Collectively, the present study identified a novel miR­301a/ZNRF3/wnt/ß­catenin signaling feedback loop that serves critical roles in glioma tumorigenesis, and that may represent a potential therapeutic target.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , MicroRNAs/metabolismo , Ubiquitina-Proteína Ligases/genética , Via de Sinalização Wnt/genética , Adulto , Idoso , Animais , Apoptose/genética , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Progressão da Doença , Retroalimentação Fisiológica , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioma/mortalidade , Glioma/patologia , Humanos , Masculino , Camundongos , MicroRNAs/genética , Pessoa de Meia-Idade , Ubiquitina-Proteína Ligases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem , beta Catenina/metabolismo
15.
Parkinsons Dis ; 2021: 6639762, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34221342

RESUMO

Deep brain stimulation (DBS) has shown a remarkably high effectiveness for Parkinson's disease (PD). In many PD patients during DBS surgery, the therapeutic effects of the stimulation test are estimated by assessing changes in bradykinesia as the stimulation voltage is increased. In this study, we evaluated the potential of the leap motion controller (LMC) to quantify the motor component of bradykinesia in PD during DBS surgery, as this could make the intraoperative assessment of bradykinesia more accurate. Seven participants with idiopathic PD receiving chronic bilateral subthalamic nucleus deep brain stimulation (DBS) therapy were recruited. The motor tasks of finger tapping (FT), hand opening and closing (OC), and hand pronation and supination (PS) were selected pre- and intraoperatively in accordance with the Movement Disorder Society revision of the Unified Parkinson's Disease Rating Scale. During the test, participants performed these tasks in sequence while being simultaneously monitored by the LMC and two professional clinicians. Key kinematic parameters differed between the preoperative and intraoperative conditions. We suggest that the average velocity ( V ¯ ) and average amplitude ( A ¯ ) of PS isolate the bradykinetic feature from that movement to provide a measure of the intraoperative state of the motor system. The LMC achieved promising results in evaluating PD patients' hand and finger bradykinesia during DBS surgery.

16.
Bioengineered ; 12(1): 3503-3515, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34233591

RESUMO

Gestational diabetes mellitus (GDM) increases the risk of fetal heart malformations, though little is known about the mechanism of hyperglycemia-induced heart malformations. Thus, we aimed to reveal the global landscape of miRNAs and mRNAs in GDM-exposed fetoplacental arterial endothelial cells (dAECs) and establish regulatory networks for exploring the pathophysiological mechanism of fetal heart malformations in maternal hyperglycemia. Gene Expression Omnibus (GEO) datasets were used, and identification of differentially expressed miRNAs (DEMs) and genes (DEGs) in GDM was based on a previous sequencing analysis of dAECs. A miRNA-mRNA network containing 20 DEMs and 65 DEGs was established using DEMs altered in opposite directions to DEGs. In an in vivo study, we established a streptozotocin-induced pregestational diabetes mellitus (PGDM) mouse model and found the fetal cardiac wall thickness in different regions to be dramatically increased in the PGDM grouValidation of DEMs and DEGs in the fetal heart showed significantly upregulated expression of let-7e-5p, miR-139-5p and miR-195-5p and downregulated expression of SGOL1, RRM2, RGS5, CDK1 and CENPA. In summary, we reveal the miRNA-mRNA regulatory network related to fetal cardiac development disorders in offspring, which may shed light on the potential molecular mechanisms of fetal cardiac development disorders during maternal hyperglycemia.


Assuntos
Diabetes Gestacional/metabolismo , Células Endoteliais , MicroRNAs/genética , RNA Mensageiro/genética , Transcriptoma/genética , Animais , Células Cultivadas , Bases de Dados Genéticas , Diabetes Gestacional/genética , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Feto/irrigação sanguínea , Feto/citologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo , Placenta/irrigação sanguínea , Placenta/citologia , Gravidez , RNA Mensageiro/metabolismo
17.
Parkinsons Dis ; 2021: 5681870, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936583

RESUMO

INTRODUCTION: Postural instability is commonly observed in Parkinson's disease, leading to an increasing risk of falling and worsening as the disease progresses. We found that limit of stability can be applied to reflect the dynamic evolution of postural instability in patients with Parkinson's disease. METHODS: Forty-three patients (9 of Hoehn and Yahr stage I, 12 of stage II, 14 of stage III, and 8 of stage IV) met the criteria for the diagnosis of idiopathic Parkinson's disease and could stand independently for at least 10 minutes. Twelve healthy controls with no sign of parkinsonism were also recruited. Postural instability was assessed by posturography in different directions (forward, backward, right, left, forward-right, forward-left, backward-right, and backward-left). This study trial was registered with the Chinese Clinical Trial Registry (no. ChiCTR1900022715). RESULTS: All participants were able to complete the limit of stability tasks without any complications. Patients in stages II to IV exhibited smaller end point excursion and slower time to complete than controls, suggesting an impaired limit of stability. The patients in stage II exhibited a remarkable decline in most directions compared to controls, except for right and left, and forward and backward decline occurred the earliest. For patients in stage III, right was the only direction with no significant difference from controls. In stage IV patients, the limit of stability declined significantly in all directions (p < 0.05). CONCLUSIONS: The postural abnormalities of Parkinson's disease can occur at early stages, and the pattern of decline is more severe in the forward-backward direction. This trial is registered with ChiCTR1900022715.

18.
Medicine (Baltimore) ; 99(27): e20989, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32629715

RESUMO

BACKGROUND: Many genetic diseases are known to have distinctive facial phenotypes, which are highly informative to provide an opportunity for automated detection. However, the diagnostic performance of artificial intelligence to identify genetic diseases with facial phenotypes requires further investigation. The objectives of this systematic review and meta-analysis are to evaluate the diagnostic accuracy of artificial intelligence to identify the genetic diseases with face phenotypes and then find the best algorithm. METHODS: The systematic review will be conducted in accordance with the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols" guidelines. The following electronic databases will be searched: PubMed, Web of Science, IEEE, Ovid, Cochrane Library, EMBASE and China National Knowledge Infrastructure. Two reviewers will screen and select the titles and abstracts of the studies retrieved independently during the database searches and perform full-text reviews and extract available data. The main outcome measures include diagnostic accuracy, as defined by accuracy, recall, specificity, and precision. The descriptive forest plot and summary receiver operating characteristic curves will be used to represent the performance of diagnostic tests. Subgroup analysis will be performed for different algorithms aided diagnosis tests. The quality of study characteristics and methodology will be assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Data will be synthesized by RevMan 5.3 and Meta-disc 1.4 software. RESULTS: The findings of this systematic review and meta-analysis will be disseminated in a relevant peer-reviewed journal and academic presentations. CONCLUSION: To our knowledge, there have not been any systematic review or meta-analysis relating to diagnosis performance of artificial intelligence in identifying the genetic diseases with face phenotypes. The findings would provide evidence to formulate a comprehensive understanding of applications using artificial intelligence in identifying the genetic diseases with face phenotypes and add considerable value in the future of precision medicine. OSF REGISTRATION: DOI 10.17605/OSF.IO/P9KUH.


Assuntos
Face/anormalidades , Doenças Genéticas Inatas/diagnóstico , Aprendizado Profundo , Humanos , Desenvolvimento Maxilofacial/genética , Metanálise como Assunto , Fenótipo , Revisões Sistemáticas como Assunto
19.
Diagnostics (Basel) ; 10(7)2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32709157

RESUMO

Down syndrome is one of the most common genetic disorders. The distinctive facial features of Down syndrome provide an opportunity for automatic identification. Recent studies showed that facial recognition technologies have the capability to identify genetic disorders. However, there is a paucity of studies on the automatic identification of Down syndrome with facial recognition technologies, especially using deep convolutional neural networks. Here, we developed a Down syndrome identification method utilizing facial images and deep convolutional neural networks, which quantified the binary classification problem of distinguishing subjects with Down syndrome from healthy subjects based on unconstrained two-dimensional images. The network was trained in two main steps: First, we formed a general facial recognition network using a large-scale face identity database (10,562 subjects) and then trained (70%) and tested (30%) a dataset of 148 Down syndrome and 257 healthy images curated through public databases. In the final testing, the deep convolutional neural network achieved 95.87% accuracy, 93.18% recall, and 97.40% specificity in Down syndrome identification. Our findings indicate that the deep convolutional neural network has the potential to support the fast, accurate, and fully automatic identification of Down syndrome and could add considerable value to the future of precision medicine.

20.
Elife ; 72018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29547120

RESUMO

Microtubules control different aspects of cell polarization. In cells with a radial microtubule system, a pivotal role in setting up asymmetry is attributed to the relative positioning of the centrosome and the nucleus. Here, we show that centrosome loss had no effect on the ability of endothelial cells to polarize and move in 2D and 3D environments. In contrast, non-centrosomal microtubules stabilized by the microtubule minus-end-binding protein CAMSAP2 were required for directional migration on 2D substrates and for the establishment of polarized cell morphology in soft 3D matrices. CAMSAP2 was also important for persistent endothelial cell sprouting during in vivo zebrafish vessel development. In the absence of CAMSAP2, cell polarization in 3D could be partly rescued by centrosome depletion, indicating that in these conditions the centrosome inhibited cell polarity. We propose that CAMSAP2-protected non-centrosomal microtubules are needed for establishing cell asymmetry by enabling microtubule enrichment in a single-cell protrusion.


Assuntos
Polaridade Celular/fisiologia , Células Endoteliais/fisiologia , Microtúbulos/metabolismo , Neovascularização Fisiológica/fisiologia , Animais , Animais Geneticamente Modificados , Movimento Celular/fisiologia , Células Cultivadas , Centrossomo/metabolismo , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Complexo de Golgi/metabolismo , Humanos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Interferência de RNA , Peixe-Zebra
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA