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1.
Artigo em Inglês | MEDLINE | ID: mdl-38843065

RESUMO

Prognostic risk prediction is pivotal for clinicians to appraise the patient's esophageal squamous cell cancer (ESCC) progression status precisely and tailor individualized therapy treatment plans. Currently, CT-based multi-modal prognostic risk prediction methods have gradually attracted the attention of researchers for their universality, which is also able to be applied in scenarios of preoperative prognostic risk assessment in the early stages of cancer. However, much of the current work focuses only on CT images of the primary tumor, ignoring the important role that CT images of lymph nodes play in prognostic risk prediction. Additionally, it is important to consider and explore the inter-patient feature similarity in prognosis when developing models. To solve these problems, we proposed a novel multi-modal population-graph based framework leveraging CT images including primary tumor and lymph nodes combined with clinical, hematology, and radiomics data for ESCC prognostic risk prediction. A patient population graph was constructed to excavate the homogeneity and heterogeneity of inter-patient feature embedding. Moreover, a novel node-level multi-task joint loss was proposed for graph model optimization through a supervised-based task and an unsupervised-based task. Sufficient experimental results show that our model achieved state-of-the-art performance compared with other baseline models as well as the gold standard on discriminative ability, risk stratification, and clinical utility. The core code is available at https://github.com/wuchengyu123/MPGSurv.

2.
Sci Rep ; 13(1): 17597, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37845346

RESUMO

The intestinal epithelium is highly regenerative. Rapidly proliferating LGR5+ crypt base columnar (CBC) cells are responsible for epithelial turnover needed to maintain intestinal homeostasis. Upon tissue damage, loss of LGR5+ CBCs can be compensated by activation of quiescent +4 intestinal stem cells (ISCs) or early progenitor cells to restore intestinal regeneration. LGR5+ CBC self-renewal and ISC conversion to LGR5+ cells are regulated by external signals originating from the ISC niche. In contrast, little is known about intrinsic regulatory mechanisms critical for maintenance of LGR5+ CBC homeostasis. We found that LGR5 expression in intestinal crypt cells is controlled by the circadian core clock gene BMAL1 and the BMAL1-regulated RNA-binding protein MEX3A. BMAL1 directly activated transcription of Mex3a. MEX3A in turn bound to and stabilized Lgr5 mRNA. Bmal1 depletion reduced Mex3a and Lgr5 expression and led to increased ferroptosis, which consequently decreased LGR5+ CBC numbers and increased the number of crypt cells expressing +4 ISC marker BMI1. Together, these findings reveal a BMAL1-centered intrinsic regulatory pathway that maintains LGR5 expression in the crypt cells and suggest a potential mechanism contributing to ISC homeostasis.


Assuntos
Fatores de Transcrição ARNTL , Intestinos , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Mucosa Intestinal/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
3.
Nanomaterials (Basel) ; 13(13)2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37446441

RESUMO

In recent years, LC resonant sensors have gained widespread attention for their extensive applications in industries such as pharmaceutical storage and food transportation. A wireless passive sensor with a good sensing performance is proposed based on a GO/CNT-OH/Nafion nanocomposite. The sensor was fabricated via inkjet printing technology, and the surface morphology of the GO/CNT-OH/Nafion nanocomposite was characterized by SEM measurement. It is found that the MWCNTs support the GO layer and the hydrophobic chains of Nafion interact with the hydrophobic layer of GO, resulting in a larger cavity and hydrophilic surface of the entire material. This structure well reflects the fact that the mixing of MWCNTs and Nafion provides the entire material with a stronger water absorption. The experimental study shows that the proposed humidity sensor has a frequency variation of 103 kHz/%RH at low humidity (30-60% RH) and a sensitivity of 931 kHz/%RH at high humidity (60-95% RH), while the sensitivity value from 30-95% RH is 547 kHz/% RH. The response time and recovery time are 110 s and 115 s, respectively. In addition, the tests showed that the GO/CNT-OH/Nafion nanocomposite applied to the humidity sensor had a maximum humidity hysteresis of about 3% RH at 30-95% RH, the resonant frequency remained basically unchanged after 50 h of testing, and the whole sensor possessed a good stability. After conducting several repeated experiments, it was found that the resonant frequency error of the whole sensor was low and did not affect the overall sensing test, which proved the reproducible preparation of the sensor. Finally, the humidity-sensing mechanism of the proposed sensor was analyzed in this paper, and it was found that GO enhanced the hygroscopic properties of GO/CNT-OH/Nafion nanocomposite when it was supported by MWCNT-OH and included uniformly dispersed Nafion. Therefore, our proposed humidity sensor is suitable for humidity detection above 30% RH in both sealed and open environments.

4.
Sci Rep ; 13(1): 11171, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37430100

RESUMO

Large Scale Natural Draft Cooling Tower has become a hot topic in China because it is an important part of the nuclear power plant, and its environmental impacts include shading, solar energy loss, water deposition and salt deposition. In China, there is no built large-scale natural draft cooling tower of nuclear power plant. Therefore, model prediction becomes an effective way to solve this problem. This paper introduces the basic principles and structure of SACTI (Seasonal and Annual Cooling Tower Impact) model. SACTI is a cooling tower assessment model developed by Argonne National Laboratory, USA. A comparative case study between China's Pengze Nuclear Power Plant and the US Amos Power Plant is also presented. Calculations were carried out for the Pengze and Amos power plants, and the results showed that the maximum value of salt deposition at the Pengze plant was about 166.5 kg/(km2-month) at a distance of 800 m from the cooling tower. The maximum value of salt deposition at the Amos plant was about 92.85 kg/(km2-month) at a distance of 600 m from the cooling tower. Conclusions show that the research work can provide a useful solution in future work, the simulation results of the SACTI model have a potential mean in the absence of monitoring data. This research provides a way to generate simulation data through SACTI program in the design process of nuclear power plant cooling tower, and designers can use these data to determine how the cooling tower will affect the natural environment and manage within an appropriate range to reduce the impact on the environment.

5.
Nanomaterials (Basel) ; 13(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36770426

RESUMO

In recent years, with the rapid development of flexible electronic devices, researchers have a great interest in the research of electronic skin (e-skin). Traditional e-skin, which is made of rigid integrated circuit chips, not only limits the overall flexibility, but also consumes a lot of power and poses certain security risks to the human body. In this paper, a wireless passive e-skin is designed based on the surface acoustic wave sensor (SAWS) of lithium niobate piezoelectric film. The e-skin has the advantages of small size, high precision, low power consumption, and good flexibility. With the multi-sensing function of stress, temperature, and sweat ion concentration, etc., the newly designed e-skin is a sensor platform for a wide range of external stimuli, and the measurement results can be directly presented in frequency. In order to explore the characteristic parameters and various application scenarios of the SAWS, finite element analysis is carried out using the simulation software; the relationship between the SAWS and various influencing factors is explored, and the related performance curve is obtained. These simulation results provide important reference and experimental guidance for the design and preparation of SAW e-skin.

6.
Cancer Res ; 83(2): 251-263, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36354374

RESUMO

Epithelial ovarian cancer is a highly heterogeneous and malignant female cancer with an overall low survival rate. Mutations in p53 are prevalent in the major ovarian cancer histotype, high-grade serous ovarian carcinoma (HGSOC), while p53 mutations are much less frequent in other ovarian cancer subtypes, particularly in ovarian clear cell carcinoma (OCCC). Advanced stage OCCC with wild-type (WT) p53 has a worse prognosis and increased drug resistance, metastasis, and recurrence than HGSOC. The mechanisms responsible for driving the aggressiveness of WT p53-expressing ovarian cancer remain poorly understood. Here, we found that upregulation of MEX3A, a dual-function protein containing a RING finger domain and an RNA-binding domain, was critical for tumorigenesis in WT p53-expressing ovarian cancer. MEX3A overexpression enhanced the growth and clonogenicity of OCCC cell lines. In contrast, depletion of MEX3A in OCCC cells, as well as ovarian teratocarcinoma cells, reduced cell survival and proliferative ability. MEX3A depletion also inhibited tumor growth and prolonged survival in orthotopic xenograft models. MEX3A depletion did not alter p53 mRNA level but did increase p53 protein stability. MEX3A-mediated p53 protein degradation was crucial to suppress ferroptosis and enhance tumorigenesis. Consistently, p53 knockdown reversed the effects of MEX3A depletion. Together, our observations identified MEX3A as an important oncogenic factor promoting tumorigenesis in ovarian cancer cells expressing WT p53. SIGNIFICANCE: Degradation of p53 mediated by MEX3A drives ovarian cancer growth by circumventing p53 tumor suppressive functions, suggesting targeting MEX3A as a potential strategy for treating of ovarian cancer expressing WT p53.


Assuntos
Adenocarcinoma de Células Claras , Ferroptose , Neoplasias Ovarianas , Proteínas de Ligação a RNA , Proteína Supressora de Tumor p53 , Feminino , Humanos , Adenocarcinoma de Células Claras/tratamento farmacológico , Carcinogênese/genética , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Ferroptose/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
7.
Lancet Neurol ; 21(4): 319-328, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35219379

RESUMO

BACKGROUND: Early enteral nutrition is crucial for preventing malnutrition and improving outcomes in patients with severe stroke, but previous trials have provided conflicting results regarding the optimal nutritional strategy. We aimed to compare the efficacy and safety of three enteral feeding strategies in patients with severe stroke. METHODS: The Optimizing Early Enteral Nutrition in Severe Stroke (OPENS) study was a multicentre, investigator-initiated, prospective, open-label, randomised controlled trial, with blinded outcome assessment, in 16 tertiary and district general hospitals in the west of China. Adult patients with acute severe ischaemic or haemorrhagic stroke (Glasgow Coma Scale score ≤12 or National Institutes of Health Stroke Scale score ≥11 on admission) who were expected to receive enteral nutrition for more than 7 days were randomly assigned (1:1:1) to full enteral nutrition (70-100% of estimated caloric requirements), modified full enteral nutrition (full enteral nutrition plus prokinetic agents), or hypocaloric enteral nutrition (40-60% of estimated caloric requirements) via a centralised web-based randomisation system. The assigned nutrition was initiated within 24 h after enrolment and continued for 7 days. The computer-generated randomisation sequence was prepared by a statistician not involved with the rest of the study. Randomisation was done with an automated permuted block size of six. The allocation was unblinded to participants and investigators. The primary efficacy outcome was the proportion of participants with poor outcome (modified Rankin Scale score ≥3) at day 90 and the prespecified primary safety outcome was mortality at day 90, assessed in the intention-to-treat population. The trial is registered with ClinicalTrials.gov, NCT02982668. FINDINGS: Between Jan 15, 2017, and Sept 23, 2020, 321 patients were randomly assigned (107 in each group) and 315 patients (175 [56%] men, median age 71 years, IQR 60-78) were included in the final analysis. The study was terminated ahead of schedule on Sept 23, 2020, because a significant difference between groups was detected in mortality. The proportion of participants with poor outcomes at 90 days did not differ (modified full enteral nutrition 86 [82%] of 105 patients vs full enteral nutrition 85 [80%] of 106 patients, adjusted odds ratio [OR] 0·87, 95% CI 0·41-1·86, p=0·721; hypocaloric enteral nutrition 76 [73%] of 104 patients vs full enteral nutrition 0·61, 0·30-1·27, p=0·186; hypocaloric enteral nutrition vs modified full enteral nutrition 0·70, 0·34-1·46, p=0·340). Hypocaloric enteral nutrition showed significantly higher 90-day mortality than did modified full enteral nutrition (35 [34%] of 104 patients vs 18 [17%] of 105 patients, adjusted OR 2·89, 95% CI 1·46-5·72; p=0·0023), whereas the difference was not significant between hypocaloric enteral nutrition and full enteral nutrition (24 [23%] of 106 patients; adjusted OR 1·92, 95% CI 1·00-3·69; p=0·049), and between modified full enteral nutrition and full enteral nutrition (adjusted OR 0·61, 0·29-1·28; p=0·187). The most common adverse event was pneumonia, the incidence of which showed no significant difference among groups (full enteral nutrition 82 [78%] of 105 patients, modified full enteral nutrition 83 [81%] of 103 patients, hypocaloric enteral nutrition 78 [75%] of 104 patients; p=0·625). INTERPRETATION: In the early phase of severe stroke, modified full enteral nutrition or hypocaloric enteral nutrition did not significantly reduce the risk of a poor outcomes compared with full enteral nutrition over a 90-day period. Hypocaloric enteral nutrition might be associated with increased mortality compared with modified full enteral nutrition. Further studies are needed to investigate whether modified full enteral nutrition might be the optimal strategy. FUNDING: Shaanxi province Key Research and Development Project.


Assuntos
Nutrição Enteral , Acidente Vascular Cerebral , Adulto , Idoso , Feminino , Humanos , Masculino , Razão de Chances , Avaliação de Resultados em Cuidados de Saúde , Estudos Prospectivos , Resultado do Tratamento
8.
Ann Clin Transl Neurol ; 8(10): 2059-2069, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34587373

RESUMO

OBJECTIVE: To explore the effect of individualized blood pressure (BP)-lowering treatment on the outcomes of elderly patients with severe intracerebral hemorrhage (ICH). METHODS: We performed an exploratory analysis of Controlling Hypertension After Severe Cerebrovascular Event (CHASE) trial, which was a multicenter, randomized, controlled clinical trial. Patients with severe ischemic or hemorrhagic stroke (defined as GCS ≤ 12 or NIHSS ≥ 11) were randomized into individualized versus standard BP-lowering treatment in CHASE trial. In this exploratory analysis, patients with severe ICH were included. The primary outcome was the percentage of patients with 90-day functional independence defined as modified Rankin Scale (mRS) ≤2. RESULTS: We included 242 patients with severe ICH in the present analysis, consisting of 142 patients aged <65 years and 100 patients aged ≥65 years. There were significant differences between patients aged ≥65 years and <65 years in the proportion of functional independence (47.9% vs. 15.0%, P < 0.001) and good outcome (73.9% vs. 50.0%, P < 0.001) at day 90. In patients aged ≥65 years, the adjusted individualized BP-lowering treatment had an unequivocal effect on the functional independence at day 90 (21.6% vs. 8.2%, odds ratio [OR]: 4.309, 95% confidence interval [CI]: 1.040-17.859, P = 0.044) and improved the neurological deficits at discharge (∆ NIHSS ≥ 4: 64.7% vs. 34.7%, OR: 4.300, 95% CI: 1.599-11.563, P = 0.004). INTERPRETATION: Compared with the younger counterparts, the elderly patients (≥65 years) with acute severe ICH might benefit more from individualized BP-lowering treatment.


Assuntos
Anti-Hipertensivos/farmacologia , Hemorragia Cerebral/tratamento farmacológico , Hipertensão/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Acidente Vascular Cerebral/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anti-Hipertensivos/administração & dosagem , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente
9.
Int J Stroke ; 16(4): 456-465, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-32525464

RESUMO

BACKGROUND: The optimal blood pressure lowering target in the acute phase of severe stroke is uncertain. Our aim was to compare the efficacy and safety of individualized blood pressure lowering with standard blood pressure lowering in severe stroke. METHODS: Five-hundred consecutive patients with acute severe stroke and elevated BP were recruited from 26 Chinese hospitals. Eligible patients were randomized into an individualized blood pressure lowering group (with 10-15% reduction in systolic blood pressure from admission level or standard blood pressure lowering group (with a target SBP of <200 mm Hg in acute ischemic stroke and <180 mm Hg in intracerebral hemorrhage). The primary outcome was the proportion of patients with a poor functional outcome at day 90 of enrolment. RESULTS: Of 483 participants included in the analysis, 242 received individualized blood pressure lowering treatment and 241 received standard treatment. The primary outcome event was observed in 71.1% of the participants in the individualized treatment group and in 73.4% of the standard treatment group (odds ratio with individualized treatment for primary outcome, 0.75; 95% confidence interval, 0.47 to 1.19; p = 0.222). The rates of serious adverse events in the two groups were similar (27.7% vs. 28.2%). CONCLUSIONS: In patients with acute severe stoke, individualized blood pressure lowering treatment did not significantly reduce the rate of three-month death or dependence. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02982655. Registered in 5 December 2016, https://clinicaltrials.gov/ct2/show/NCT02982655.


Assuntos
Isquemia Encefálica , Hipertensão , Acidente Vascular Cerebral , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Isquemia Encefálica/tratamento farmacológico , Humanos , Hipertensão/tratamento farmacológico , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento
10.
J Clin Hypertens (Greenwich) ; 23(1): 96-102, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33226186

RESUMO

The influence of blood pressure variability (BPV) on outcomes in patients with severe stroke is still largely unsettled. Using the data of CHASE trial, the authors calculated the BPV during the acute phase and subacute phase of severe stroke, respectively. The primary outcome was to investigate the relationship between BPV and 90-day modified Rankin scale (mRS) ≥ 3. The BPV was assessed by eight measurements including standard deviation (SD), mean, maximum, minimum, coefficient of variation (CV), successive variation (SV), functional successive variation (FSV), and average real variability (ARV). Then, the SD of SBP was divided into quintiles and compared the quintile using logistic regression in three models. The acute phase included 442 patients, and the subacute phase included 390 patients. After adjustment, six measurements of BPV during the subacute phase rather than acute phase were strongly correlated with outcomes including minimum (odds ratio [OR]: 0.83, 95% confidence interval [CI]: 0.69-0.99, p = .037), SD (OR: 1.10, 95% CI: 1.03-1.17, p = .007), CV (OR: 1.12, 95% CI: 1.03-1.23, p = .012), ARV (OR: 1.13, 95% CI: 1.05-1.20, p < .001), SV (OR: 1.09, 95% CI: 1.04-1.15, p = .001), and FSV (OR: 1.12, 95% CI: 1.05-1.19, p = .001). In the logistic regression, the highest fifth of SD of SBP predicted poor outcome in all three models. In conclusion, the increased BPV was strongly correlated with poor outcomes in the subacute phase of severe stroke, and the magnitude of association was progressively increased when the SD of BP was above 12.


Assuntos
Hipertensão , Acidente Vascular Cerebral , Pressão Sanguínea , Humanos , Hipertensão/diagnóstico , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Modelos Logísticos , Razão de Chances , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia
11.
Cells ; 9(7)2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708730

RESUMO

Human embryonic stem cells (hESCs) have important roles in regenerative medicine, but only a few studies have investigated the cytokines secreted by hESCs. We screened and identified chemokine (C-X-C motif) ligand 14 (CXCL14), which plays crucial roles in hESC renewal. CXCL14, a C-X-C motif chemokine, is also named as breast and kidney-expressed chemokine (BRAK), B cell and monocyte-activated chemokine (BMAC), and macrophage inflammatory protein-2γ (MIP-2γ). Knockdown of CXCL14 disrupted the hESC self-renewal, changed cell cycle distribution, and further increased the expression levels of mesoderm and endoderm differentiated markers. Interestingly, we demonstrated that CXCL14 is the ligand for the insulin-like growth factor 1 receptor (IGF-1R), and it can activate IGF-1R signal transduction to support hESC renewal. Currently published literature indicates that all receptors in the CXCL family are G protein-coupled receptors (GPCRs). This report is the first to demonstrate that a CXCL protein can bind to and activate a receptor tyrosine kinase (RTK), and also the first to show that IGF-1R has another ligand in addition to IGFs. These findings broaden our understanding of stem cell biology and signal transduction.


Assuntos
Autorrenovação Celular , Quimiocinas CXC/metabolismo , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular , Linhagem Celular , Técnicas de Silenciamento de Genes , Humanos , Modelos Biológicos , Ligação Proteica , RNA Interferente Pequeno/metabolismo
12.
Medicine (Baltimore) ; 98(35): e16844, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31464911

RESUMO

RATIONALE: Facial nerve schwannoma (FNS) is a rare slow-growing nerve sheath tumor derived from Schwann cells. FNS with normal facial nerve function may sometimes be misdiagnosed as otitis media because of similar ontological symptoms such as purulence, tympanic membrane damage, and hearing loss. PATIENT CONCERNS: A 68-year-old woman was referred to our department because of otorrhea and hearing loss in the right ear for 20 years. Otoscopy revealed abundant purulent secretions deep in the right external auditory canal, and granulation proliferation in the posterior part of membranae tensa. Audiogram showed a right mixed hearing loss with an 85-dB pure-tone average and 35-dB air-bone gap. DIAGNOSIS: This patient was misdiagnosed as chronic suppurative otitis media before surgery. During surgery, a mass was found, and intraoperative frozen section histopathology confirmed an FNS. INTERVENTIONS: This patient was subjected to mastoidectomy for curing chronic suppurative otitis media initially. During surgery, a mass was found attached and widely extended into the tympanic and mastoid segments. We removed most part of the mass, however found the mass deriving from the vertical part of the facial nerve. Intraoperative frozen section histopathology confirmed an FNS. So we removed the incurs and malleus, and searched for the edge of the mass. The mass involved multisegments of facial nerve including the tympanic, vertical and pyramidal segments. The tumor was removed completely, and nerves were repaired using greater auricular nerves. OUTCOMES: After surgery, the patient had facial nerve paralysis of House-Brackmann (HB) Grade VI. Facial function recovered to HB Grade III at 30 months after surgery. The patient was followed up for 5 years. She had a facial function of HB grade III at the most recent follow-up. LESSONS: FNS is rare and tend to be misdiagnosed. It is important to combine the imaging modalities of computed tomography and magnetic resonance imaging to evaluate FNS before surgery. The primary goal of managing FNS is to maintain normal facial function as long as possible; therefore, tailored strategy should be taken for managing FNS.


Assuntos
Nervo Facial/cirurgia , Neurilemoma/diagnóstico , Neurilemoma/cirurgia , Idoso , Erros de Diagnóstico , Nervo Facial/patologia , Feminino , Humanos , Mastoidectomia , Neurilemoma/patologia , Otite Média Supurativa/cirurgia , Recuperação de Função Fisiológica
13.
FASEB J ; 33(9): 10577-10592, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31242772

RESUMO

We reveal by high-throughput screening that activating transcription factor 1 (ATF1) is a novel pluripotent regulator in human embryonic stem cells (hESCs). The knockdown of ATF1 expression significantly up-regulated neuroectoderm (NE) genes but not mesoderm, endoderm, and trophectoderm genes. Of note, down-regulation or knockout of ATF1 with short hairpin RNA (shRNA), small interfering RNA (siRNA), or clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) was sufficient to up-regulate sex-determining region Y-box (SOX)2 and paired box 6 (PAX6) expression under the undifferentiated or differentiated conditions, whereas overexpression of ATF1 suppressed NE differentiation. Endogenous ATF1 was spontaneously down-regulated after d 1-3 of neural induction. By double-knockdown experiments, up-regulation of SOX2 was critical for the increase of PAX6 and SOX1 expression in shRNA targeting Atf1 hESCs. Using the luciferase reporter assay, we identified ATF1 as a negative transcriptional regulator of Sox2 gene expression. A novel function of ATF1 was discovered, and these findings contribute to a broader understanding of the very first steps in regulating NE differentiation in hESCs.-Yang, S.-C., Liu, J.-J., Wang, C.-K., Lin, Y.-T., Tsai, S.-Y., Chen, W.-J., Huang, W.-K., Tu, P.-W. A., Lin, Y.-C., Chang, C.-F., Cheng, C.-L., Lin, H., Lai, C.-Y., Lin, C.-Y., Lee, Y.-H., Chiu, Y.-C., Hsu, C.-C., Hsu, S.-C., Hsiao, M., Schuyler, S. C., Lu, F. L., Lu, J. Down-regulation of ATF1 leads to early neuroectoderm differentiation of human embryonic stem cells by increasing the expression level of SOX2.


Assuntos
Fator 1 Ativador da Transcrição/metabolismo , Diferenciação Celular , Regulação da Expressão Gênica no Desenvolvimento , Células-Tronco Embrionárias Humanas/citologia , Neurônios/citologia , RNA Interferente Pequeno/genética , Fatores de Transcrição SOXB1/metabolismo , Fator 1 Ativador da Transcrição/antagonistas & inibidores , Fator 1 Ativador da Transcrição/genética , Células Cultivadas , Regulação para Baixo , Endoderma/citologia , Endoderma/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Mesoderma/citologia , Mesoderma/metabolismo , Neurônios/metabolismo , Fatores de Transcrição SOXB1/genética
14.
BMC Neurol ; 19(1): 24, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755171

RESUMO

BACKGROUND: Malnutrition is one of the crucial factors associated with poor prognosis in critical ill patients, yet a significant evidence gap surrounds the management of initial enteral feeding in severe stroke. The Optimizing Early Enteral Nutrition in Severe Stroke (OPENS) trial will compare a strategy of modified full enteral nutrition (EN) (standard full EN in conjunction with prokinetic drug) and a strategy of permissive underfeeding (40 to 60% of estimated caloric requirements) with standard full EN (advancement to target nutrition goals) in patients with severe stroke. METHODS: The OPENS trial is a multicenter randomized controlled study. A total of 600 adult patients with severe stroke will be enrolled in 12 study sites in China, and randomized to standard full EN, modified full EN, or permissive underfeeding. The primary outcome measurement is the proportion of participants with a poor outcome (modified Rankin Scale ≥3) at day 90 of enrollment. Secondary outcomes include incidence rates of complications during hospitalization, disability at hospital discharge, and the ability of activities of daily living at day 90 of enrollment. The relationship between intervention and the primary outcome will be analyzed using multivariate logistic regression adjusted for study site, demographics, and baseline characteristics. DISCUSSION: The OPENS trial will explore the optimum initial feeding strategy for acute severe stroke. This trial is, therefore, an important step in bridging the evidence gap surrounding the enteral feeding for patients with severe stroke during the first week of hospitalization. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02982668 ; First Posted: December 5, 2016.


Assuntos
Nutrição Enteral/métodos , Projetos de Pesquisa , Acidente Vascular Cerebral/terapia , Adulto , Idoso , China , Estado Terminal/terapia , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Estado Nutricional
15.
Free Radic Biol Med ; 113: 439-451, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29054545

RESUMO

Glutathione (GSH), the major non-enzymatic antioxidant, plays a critical role in cellular reactive oxygen species (ROS) neutralization. Moreover, GSH is required for the self-renewal maintenance of human embryonic stem cells (hESCs), and is highly accumulated in undifferentiated cells. Among 8 GSH biosynthesis-related enzymes, we found CHAC2 is highly enriched in undifferentiated hESCs. CHAC2 downregulation in hESCs efficiently decreased the levels of GSH and blocked self-renewal. The self-renewal of sh-CHAC2 cells can be rescued by GSH supplement. CHAC2 downregulation promoted mesoderm differentiation and hampered both teratoma formation and the expression of Nrf2 and glutamate-cysteine ligase (GCL). Notably, CHAC1 knockdown restored the self-renewability of CHAC2-downregulated cells. Although both CHAC1 and CHAC2 purified protein alone showed the catalytic activities to GSH, our data extraordinarily revealed that CHAC2 prevented CHAC1-mediated GSH degradation, which suggests that CHAC2 competes with CHAC1 to maintain GSH homeostasis. This is the first report to demonstrate that CHAC2 is critical for GSH maintenance and the novel roles of the CHAC family in hESC renewal.


Assuntos
Glutamato-Cisteína Ligase/genética , Glutationa/biossíntese , Células-Tronco Embrionárias Humanas/enzimologia , Fator 2 Relacionado a NF-E2/genética , gama-Glutamilciclotransferase/genética , Animais , Bioensaio , Linhagem Celular , Proliferação de Células , Células Alimentadoras/citologia , Fibroblastos/citologia , Regulação da Expressão Gênica , Glutamato-Cisteína Ligase/metabolismo , Glutationa/genética , Células-Tronco Embrionárias Humanas/citologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Teratoma/enzimologia , Teratoma/genética , Teratoma/patologia , gama-Glutamilciclotransferase/antagonistas & inibidores , gama-Glutamilciclotransferase/metabolismo
16.
Sci Rep ; 7(1): 5289, 2017 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-28706279

RESUMO

An important safety concern in the use of human pluripotent stem cells (hPSCs) is tumorigenic risk, because these cells can form teratomas after an in vivo injection at ectopic sites. Several thousands of undifferentiated hPSCs are sufficient to induce teratomas in a mouse model. Thus, it is critical to remove all residue-undifferentiated hPSCs that have teratoma potential before the clinical application of hPSC-derived cells. In this study, our data demonstrated the cytotoxic effects of cardiac glycosides, such as digoxin, lanatoside C, bufalin, and proscillaridin A, in human embryonic stem cells (hESCs). This phenomenon was not observed in human bone marrow mesenchymal stem cells (hBMMSCs). Most importantly, digoxin and lanatoside C did not affect the stem cells' differentiation ability. Consistently, the viability of the hESC-derived MSCs, neurons, and endothelium cells was not affected by the digoxin and lanatoside C treatment. Furthermore, the in vivo experiments demonstrated that digoxin and lanatoside C prevented teratoma formation. To the best of our knowledge, this study is the first to describe the cytotoxicity and tumor prevention effects of cardiac glycosides in hESCs. Digoxin and lanatoside C are also the first FDA-approved drugs that demonstrated cytotoxicity in undifferentiated hESCs.


Assuntos
Adipogenia/efeitos dos fármacos , Glicosídeos Cardíacos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Embrionárias Humanas/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Teratoma/prevenção & controle , Animais , Técnicas de Cultura de Células , Células Cultivadas , Células-Tronco Embrionárias Humanas/patologia , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Teratoma/metabolismo , Teratoma/patologia
17.
Br J Radiol ; 89(1062): 20150783, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27042802

RESUMO

OBJECTIVE: Recently, a new catheter-based (32)P brachytherapy source has been developed (College of Chemistry, Sichuan University) for use in high-dose-rate afterloader. This study presents the results of the dosimetric data of the Geant4 Monte Carlo (MC) simulation toolkit for this new (32)P brachytherapy source. METHODS: The new (32)P source had dimensions of 0.50-cm length and 0.08-cm diameter and was encapsulated in teflon. In this study, we attempted to obtain dosimetric data for this new source, as required by the formalism proposed by the American Association of Physicists in Medicine reports TG60 and TG149. The source was located in a 30-cm radius theoretical sphere water phantom, and the absorbed dose of the source was calculated using MC code. RESULTS: The dosimetric data included the reference absorbed dose rate, the radial dose function in the range of 0.10-0.50 cm at a longitudinal axis, the polynomial function for the radial dose function and the anisotropy function with a θ value of 0-90° in 5° intervals and an r of 0.10-0.35 cm in 0.01-cm intervals. The radial and axial dose profiles and away-along quality assurance table are also calculated for the unsheathed (32)P source. The dose rate D(r0,θ0) at the reference point for the unsheathed (32)P source is determined to be equal to 1.2660 ± 0.0006 cGy s(-1) mCi. The radial dose function of the new (32)P source shows good agreement with the other (32)P source presented in this work with an average difference of 1.78%. CONCLUSION: Dosimetric data are provided for the new (32)P source. These data could be used in treatment-planning systems in clinical practice. ADVANCES IN KNOWLEDGE: Provided a new beta-emitting brachytherapy source that is intended for treatment of liver cancer. A dosimetric study of the unsheathed (32)P source for which no published dosimetric data existed was performed.


Assuntos
Braquiterapia/instrumentação , Modelos Estatísticos , Método de Monte Carlo , Radioisótopos de Fósforo/análise , Radiometria/métodos , Braquiterapia/métodos , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Próteses e Implantes , Dosagem Radioterapêutica , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade
18.
Opt Express ; 21(12): 14606-17, 2013 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-23787648

RESUMO

We propose and demonstrate a facile approach for ultraviolet-visible broadband generation from a sapphire crystal core-borosilicate glass cladding hybrid fiber using a laser-heated pedestal growth technique. Considerable formation of F- and F(2)-type color emitters is effectively facilitated by Ti(4+) ions and Al(3+) vacancies, retaining efficient luminescence and high crystallinity of the sapphire core. These color centers intensify the ultraviolet, blue, and green emissions at 370, 450, and 540 nm, whereas the 650-nm red emission is contributed by Cr(3+) in the octahedral sites of the corundum structure. Over 1-mW white light with an optical-to-optical efficiency of up to nearly 5% and 1931 Commission International de l'Eclairage chromaticity coordinate of (0.287, 0.333) is achieved under 325-nm excitation.


Assuntos
Tecnologia de Fibra Óptica/instrumentação , Lasers , Iluminação/instrumentação , Cor , Desenho de Equipamento , Análise de Falha de Equipamento , Raios Ultravioleta
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