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Overexpression of Kdm6b induces testicular differentiation in a temperature-dependent sex determination system
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作者 Qiran Chen Wei Sun +3 位作者 Lin Jin Yingjie Zhou Fang Li Chutian Ge 《Zoological Research》 SCIE CSCD 2024年第5期1108-1115,共8页
In reptiles,such as the red-eared slider turtle(Trachemys scripta elegans),gonadal sex determination is highly dependent on the environmental temperature during embryonic stages.This complex process,which leads to dif... In reptiles,such as the red-eared slider turtle(Trachemys scripta elegans),gonadal sex determination is highly dependent on the environmental temperature during embryonic stages.This complex process,which leads to differentiation into either testes or ovaries,is governed by the finely tuned expression of upstream genes,notably the testis-promoting gene Dmrt1 and the ovary-promoting gene Foxl2.Recent studies have identified epigenetic regulation as a crucial factor in testis development,with the H3K27me3 demethylase KDM6B being essential for Dmrt1 expression in T.s.elegans.However,whether KDM6B alone can induce testicular differentiation remains unclear.In this study,we found that overexpression of Kdm6b in T.s.elegans embryos induced the male development pathway,accompanied by a rapid increase in the gonadal expression of Dmrt1 at 31°C,a temperature typically resulting in female development.Notably,this sex reversal could be entirely rescued by Dmrt1 knockdown.These findings demonstrate that Kdm6b is sufficient for commitment to the male pathway,underscoring its role as a critical epigenetic regulator in the sex determination of the red-eared slider turtle. 展开更多
关键词 Temperature-dependent sex determination Sex reversal Kdm6b DMRT1 T.s.elegans
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Genetic Determination and Exogenous Influence in Sex Differentiation in Crustacean 被引量:4
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作者 吴长功 相建海 《Developmental and Reproductive Biology》 2002年第2期137-144,共8页
The mechanisms of sex determination and the influence of exogenous factors on sex differentiation in crustacean were reviewed in the paper.Most of crustecea have not obviously sex chromosome.Androgenic gland was repor... The mechanisms of sex determination and the influence of exogenous factors on sex differentiation in crustacean were reviewed in the paper.Most of crustecea have not obviously sex chromosome.Androgenic gland was reported as the most important sex differentiation factors,implanting or cuting AG can change the sexal characterization of larval in crustacean.Although sex differentiation of crustacean is determined by gene,it is affected by exogenous factors such as parasite,photoperiod,temperature or hormone.Most cultured species have different body weight and length between male and female,this can be used in aquaculture to produce all male or female crusteceans to improve the production. 展开更多
关键词 genetic determination exogenous influence sex differentiation CRUSTACEAN
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Photobiomodulation:a novel approach to promote trans-differentiation of adipose-derived stem cells into neuronal-like cells
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作者 Daniella Da Silva Madeleen Jansen van Rensburg +1 位作者 Anine Crous Heidi Abrahamse 《Neural Regeneration Research》 SCIE CAS 2025年第2期598-608,共11页
Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infr... Photobiomodulation,originally used red and near-infrared lasers,can alter cellular metabolism.It has been demonstrated that the visible spectrum at 451-540 nm does not necessarily increase cell proliferation,near-infrared light promotes adipose stem cell proliferation and affects adipose stem cell migration,which is necessary for the cells homing to the site of injury.In this in vitro study,we explored the potential of adipose-derived stem cells to differentiate into neurons for future translational regenerative treatments in neurodegenerative disorders and brain injuries.We investigated the effects of various biological and chemical inducers on trans-differentiation and evaluated the impact of photobiomodulation using 825 nm near-infrared and 525 nm green laser light at 5 J/cm2.As adipose-derived stem cells can be used in autologous grafting and photobiomodulation has been shown to have biostimulatory effects.Our findings reveal that adipose-derived stem cells can indeed trans-differentiate into neuronal cells when exposed to inducers,with pre-induced cells exhibiting higher rates of proliferation and trans-differentiation compared with the control group.Interestingly,green laser light stimulation led to notable morphological changes indicative of enhanced trans-differentiation,while near-infrared photobiomodulation notably increased the expression of neuronal markers.Through biochemical analysis and enzyme-linked immunosorbent assays,we observed marked improvements in viability,proliferation,membrane permeability,and mitochondrial membrane potential,as well as increased protein levels of neuron-specific enolase and ciliary neurotrophic factor.Overall,our results demonstrate the efficacy of photobiomodulation in enhancing the trans-differentiation ability of adipose-derived stem cells,offering promising prospects for their use in regenerative medicine for neurodegenerative disorders and brain injuries. 展开更多
关键词 differentiation inducers green photobiomodulation immortalized adipose-derived stem cell near-infrared photobiomodulation neurodegenerative disease NEUROGENESIS PHOTOBIOMODULATION TRANS-differentiation
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Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke
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作者 Lin-Yan Huang Yi-De Zhang +9 位作者 Jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-Yian Guo Jian-Gang Shen Su-Hua Qi 《Neural Regeneration Research》 SCIE CAS 2025年第3期845-857,共13页
It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late stroke.Indeed,previous studies have shown that excessive increases ... It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late stroke.Indeed,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain tissue.Our previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently unclear.To simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic stroke.We found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous acid.Further,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid hydrazide.Our results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/reoxygenation.However,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and astrocytes.This suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion injury.Lower levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-catenin.By transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear translocation.Altogether,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function. 展开更多
关键词 cell differentiation cerebral ischemia/reperfusion injury CHLORINATION hypochlorous acid MICROGLIA neural stem cell NEUROGENESIS nuclear translocation stroke β-catenin
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A Review of Sexual Determination and Differentiation in Crustacean 被引量:1
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作者 Jianwen Li 《Journal of Biosciences and Medicines》 CAS 2022年第7期19-37,共19页
The prerequisite for monosex culture is to elucidate the molecular mechanism of sex determination and differentiation in crustaceans, as well as to explore the key genes that play a role in this process. Monosex cultu... The prerequisite for monosex culture is to elucidate the molecular mechanism of sex determination and differentiation in crustaceans, as well as to explore the key genes that play a role in this process. Monosex culture technology based on crustacean economic species is of great importance in terms of genetic breeding and economic benefits of aquaculture. As a result, study into the mechanisms of sex determination and differentiation in crustaceans not only contributes to the current absence of basic theories of crustacean sexual mechanism, but also encourages technical innovation in aquaculture to increase overall economic efficiency. This study synthesizes and evaluates available research on sex determination and differentiation in crustaceans, and then provides recommendations for future research objectives and priorities in the field. 展开更多
关键词 CRUSTACEAN Sex determination Sex differentiation
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Sox9 is indispensable for testis differentiation in the red-eared slider turtle,a reptile with temperaturedependent sex determination 被引量:2
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作者 Hang-Bo Hui Ling Xiao +3 位作者 Wei Sun Ying-Jie Zhou Hai-Yan Zhang Chu-Tian Ge 《Zoological Research》 SCIE CAS CSCD 2021年第6期721-725,共5页
SOX9(SRY-related HMG box gene 9)is an essential regulator of male sex determination and testis differentiation in many vertebrate species.However,the functional role of Sox9 in testis differentiation has not yet been ... SOX9(SRY-related HMG box gene 9)is an essential regulator of male sex determination and testis differentiation in many vertebrate species.However,the functional role of Sox9 in testis differentiation has not yet been identified in any reptilian species.Herein,Sox9 knockdown in the red-eared slider turtle(Trachemys scripta)embryos at a male-producing temperature led to complete male-to-female sex reversal,characterized by the formation of an ovary-like structure,disappearance of male marker AMH,and ectopic expression of ovarian regulator FOXL2,as well as a female distribution pattern of germ cells.Conversely,in-ovo overexpression of Sox9 at a female-producing temperature resulted in partial masculinization of putative female embryos,with the coexistence of AMH and FOXL2.Our study provides the first direct evidence that Sox9 is indispensable for testicular differentiation in a reptilian species,further confirming the conserved role of Sox9 in vertebrate sexual development. 展开更多
关键词 SOX9 determination indispensable
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Sex Determination and Sexual Organ Differentiation in Flowering Plants
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作者 HouYanan LiFenglan GaoShumin 《Forestry Studies in China》 CAS 2004年第4期50-57,共8页
The research in the genetics of sex determination and the differentiation of reproductive organs in flowering plants has long been a topic in recent years. Understanding the genetic and molecular mechanisms that contr... The research in the genetics of sex determination and the differentiation of reproductive organs in flowering plants has long been a topic in recent years. Understanding the genetic and molecular mechanisms that control sex determination in flower- ing plants relies on detailed studies of the differentiation of sexual organs. Current theories about sex chromosomes have illuminated the mechanisms of plant sex determination. In addition, recent progress in cloning floral homeotic genes which regulate the identity of the floral organs has generated molecular markers to compare the developmental programs of male, female and hermaphrodite flowers in several species. In this review, the authors focus attention on these recent findings and provide a brief overview of the genetics of plant sex determination and the mechanism of sex determination gene expression and gene programs. 展开更多
关键词 sex determination sexual organ organ differentiation flowering plant
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Differentiation of Exophytic Renal Masses with Determination of the Angular Interface with Renal Parenchyma in US and CT
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作者 Duzgun Yildirim Halil Bozkurt +3 位作者 Abdullah Cirakoglu Mutlu Sahin Bengi Gurses Baki Ekci 《Open Journal of Medical Imaging》 2012年第2期80-83,共4页
Purpose: To determine whether benign exophytic renal masses can be distinguished from malignant lesions by using the angular interface sign in ultrasonography (US) and computerized tomography (CT). Materials and Metho... Purpose: To determine whether benign exophytic renal masses can be distinguished from malignant lesions by using the angular interface sign in ultrasonography (US) and computerized tomography (CT). Materials and Methods: A total of 71 cases with exophytic renal mass (2 cm or greater) were examined on the basis of angular interface in US (n = 23), CT (n = 21) and US + CT (n = 16) between January 2008 and June 2010 were included in this study. The renal interface relationships were examined by 2 radiologists and classified as having angular or wide interface. Results: No statistically significant difference was found between the findings of two readers. There was almost perfect interobserver agreement for the interface sign. For cystic lesions, the angular interface sign was determined in all but two Bosniak category 1 cases. Also, the angular interface sign was positive in all but one Bosniak category 2 - 3. For cystic lesions with solid component and pure solid lesions, in the benign group, the angular interface sign was positive in all except three cases (vascular malformation, oncocytoma and Xanthogranulomatous pyelonephritis). In the malignant group, the angular interface sign was determined in only two RCC cases;in other primary or metastatic malignant lesions there was a wide interface sign. Conclusion: Exophytic renal masses can be differentiated as malignant or benign with 87% accuracy using only the angular interface sign in US or CT and also in opposition to dynamic-contrast examinations. This method entails a lack of additional radiation or contrast media exposure, time-saving, and costeffectivity. 展开更多
关键词 RENAL NEOPLASMS differential Diagnosis ULTRASONOGRAPHY COMPUTED Tomography SIGN
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Combined Determination of CEA, Tch and ADA for Differential Diagnosis of Ascites 被引量:2
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作者 华国平 高岩 倪润洲 《Journal of Nanjing Medical University》 2004年第6期301-303,共3页
Objective: To study the value of combined determination of carcinoembryonic antigen (CEA), total cholesterol (Tch) and adenosine deaminase (ADA) in the differential diagnosis of ascites due to different causes. Method... Objective: To study the value of combined determination of carcinoembryonic antigen (CEA), total cholesterol (Tch) and adenosine deaminase (ADA) in the differential diagnosis of ascites due to different causes. Methods: Sixty-eight cases with ascites were divided into 3 groups based on their etiology, namely malignant ascites, tubercular ascites and non-tubercular benign ascites. CEA, Tch, and ADA were measured and analyzed in different ascites. Results: CEA was significantly higher in malignant ascites than in benign ascites, the sensitivity and specificity for malignant ascites being 50% and 100% respectively. Tch is higher or equal to 1.54 mmol/L in tubercular ascites and lower or equal to 1.18 mmol/L in non-tubercular benign ascites, and Tch level in malignant ascites was frequently between that in tubercular acites and non-tubercular benign ascites. Ascitic fluid ADA activity was higher than 30 U/L in 80% of tubercular ascites, while none of non-tubercular benign ascites reached to such level. Conclusion: CEA, Tch and ADA are valuable for the diagnosis and differential diagnosis of ascitic etiology and combine measurements of these indices can increase the diagnostic efficiency. 展开更多
关键词 ASCITES differential diagnosis carcinoembryonic antigen CHOLESTEROL adenosine deaminase
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Prognostic significance of grade of malignancy based on histopathological differentiation and Ki-67 in pancreatic ductal adenocarcinoma 被引量:2
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作者 Yuexiang Liang Guannan Sheng +7 位作者 Yu Guo Yiping Zou Hanhan Guo Zhifei Li Shaofei Chang Quan Man Song Gao Jihui Hao 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第5期416-432,共17页
Objective:Tumor cell malignancy is indicated by histopathological differentiation and cell proliferation.Ki-67,an indicator of cellular proliferation,has been used for tumor grading and classification in breast cancer... Objective:Tumor cell malignancy is indicated by histopathological differentiation and cell proliferation.Ki-67,an indicator of cellular proliferation,has been used for tumor grading and classification in breast cancer and neuroendocrine tumors.However,its prognostic significance in pancreatic ductal adenocarcinoma(PDAC)remains uncertain.Methods:Patients who underwent radical pancreatectomy for PDAC were retrospectively enrolled,and relevant prognostic factors were examined.Grade of malignancy(GOM),a novel index based on histopathological differentiation and Ki-67,is proposed,and its clinical significance was evaluated.Results:The optimal threshold for Ki-67 was determined to be 30%.Patients with a Ki-67 expression level>30%rather than≤30%had significantly shorter 5-year overall survival(OS)and recurrence-free survival(RFS).In multivariate analysis,both histopathological differentiation and Ki-67 were identified as independent prognostic factors for OS and RFS.The GOM was used to independently stratify OS and RFS into 3 tiers,regardless of TNM stage and other established prognostic factors.The tumor-nodemetastasis-GOM stage was used to stratify survival into 5 distinct tiers,and surpassed the predictive performance of TNM stage for OS and RFS.Conclusions:Ki-67 is a valuable prognostic indicator for PDAC.Inclusion of the GOM in the TNM staging system may potentially enhance prognostic accuracy for PDAC. 展开更多
关键词 Pancreatic ductal adenocarcinoma PROGNOSIS KI-67 differentiation TNM stage
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How mesenchymal stem cells transform into adipocytes:Overview of the current understanding of adipogenic differentiation 被引量:2
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作者 Shan-Shan Liu Xiang Fang +5 位作者 Xin Wen Ji-Shan Liu Miribangvl Alip Tian Sun Yuan-Yuan Wang Hong-Wei Chen 《World Journal of Stem Cells》 SCIE 2024年第3期245-256,共12页
Mesenchymal stem cells(MSCs)are stem/progenitor cells capable of self-renewal and differentiation into osteoblasts,chondrocytes and adipocytes.The transformation of multipotent MSCs to adipocytes mainly involves two s... Mesenchymal stem cells(MSCs)are stem/progenitor cells capable of self-renewal and differentiation into osteoblasts,chondrocytes and adipocytes.The transformation of multipotent MSCs to adipocytes mainly involves two subsequent steps from MSCs to preadipocytes and further preadipocytes into adipocytes,in which the process MSCs are precisely controlled to commit to the adipogenic lineage and then mature into adipocytes.Previous studies have shown that the master transcription factors C/enhancer-binding protein alpha and peroxisome proliferation activator receptor gamma play vital roles in adipogenesis.However,the mechanism underlying the adipogenic differentiation of MSCs is not fully understood.Here,the current knowledge of adipogenic differentiation in MSCs is reviewed,focusing on signaling pathways,noncoding RNAs and epigenetic effects on DNA methylation and acetylation during MSC differentiation.Finally,the relationship between maladipogenic differentiation and diseases is briefly discussed.We hope that this review can broaden and deepen our understanding of how MSCs turn into adipocytes. 展开更多
关键词 Mesenchymal stem cell Adipogenic differentiation Signaling pathway Noncoding RNA Epigenetic regulation
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Spatial-temporal differentiation and influencing factors of rural settlements in mountainous areas: an example of Liangshan Yi Autonomous Prefecture, Southwestern China 被引量:1
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作者 WANG Yumeng DENG Qingchun +3 位作者 YANG Haiqing LIU Hui YANG Feng ZHAO Yakai 《Journal of Mountain Science》 SCIE CSCD 2024年第1期218-235,共18页
Rural settlement is the basic spatial unit for compact communities in rural area. Scientific exploration of spatial-temporal differentiation and its influencing factors is the premise of spatial layout rationalization... Rural settlement is the basic spatial unit for compact communities in rural area. Scientific exploration of spatial-temporal differentiation and its influencing factors is the premise of spatial layout rationalization. Based on land use data of Liangshan Yi Autonomous Prefecture(hereinafter referred to as Liangshan Prefecture) in Sichuan Province, China from 1980 to 2020, compactness index, fractal dimension, imbalance index, location entropy and the optimal parameters-based geographical detector(OPGD) model are used to analyze the spatial-temporal evolution of the morphological characteristics of rural settlements, and to explore the influence of natural geographical factors, socioeconomic factors, and policy factors on the spatial differentiation of rural settlements. The results show that:(1) From 1980 to 2020, the rural settlements area in Liangshan Prefecture increased by 15.96 km^(2). In space, the rural settlements are generally distributed in a local aggregation, dense in the middle and sparse around the periphery. In 2015, the spatial density and expansion index of rural settlements reached the peak.(2) From 1980 to 2020, the compactness index decreased from 0.7636 to 0.7496, the fractal dimension increased from 1.0283 to 1.0314, and the fragmentation index decreased from 0.1183 to 0.1047. The spatial morphological structure of rural settlements tended to be loose, the shape contour tended to be complex, the degree of fragmentation decreased, and the spatial distribution was significantly imbalanced.(3) The results of OPGD detection in 2015 show that the influence of each factor is slope(0.2371) > traffic accessibility(0.2098) > population(0.1403) > regional GDP(0.1325) > elevation(0.0987) > poverty alleviation(0). The results of OPGD detection in 2020 show that the influence of each factor is slope(0.2339) > traffic accessibility(0.2198) > population(0.1432) > regional GDP(0.1219) > poverty alleviation(0.0992) > elevation(0.093). Natural geographical factors(slope and elevation) are the basic factors affecting the spatial distribution of rural settlements, and rural settlements are widely distributed in the river valley plain and the second half mountain area. Socioeconomic factors(traffic accessibility, population, and regional GDP) have a greater impact on the spatial distribution of rural settlements, which is an important factor affecting the spatial distribution of rural settlements. Policy factors such as poverty alleviation relocation have an indispensable impact on the spatial distribution of rural settlements. The research results can provide decisionmaking basis for the spatial arrangement of rural settlements in Liangshan Prefecture, and optimize the implementation of rural revitalization policies. 展开更多
关键词 Rural settlements Location entropy Geographical detector Spatiotemporal differentiation Influencing factors
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T2-weighted imaging-based radiomic-clinical machine learning model for predicting the differentiation of colorectal adenocarcinoma 被引量:1
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作者 Hui-Da Zheng Qiao-Yi Huang +4 位作者 Qi-Ming Huang Xiao-Ting Ke Kai Ye Shu Lin Jian-Hua Xu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第3期819-832,共14页
BACKGROUND The study on predicting the differentiation grade of colorectal cancer(CRC)based on magnetic resonance imaging(MRI)has not been reported yet.Developing a non-invasive model to predict the differentiation gr... BACKGROUND The study on predicting the differentiation grade of colorectal cancer(CRC)based on magnetic resonance imaging(MRI)has not been reported yet.Developing a non-invasive model to predict the differentiation grade of CRC is of great value.AIM To develop and validate machine learning-based models for predicting the differ-entiation grade of CRC based on T2-weighted images(T2WI).METHODS We retrospectively collected the preoperative imaging and clinical data of 315 patients with CRC who underwent surgery from March 2018 to July 2023.Patients were randomly assigned to a training cohort(n=220)or a validation cohort(n=95)at a 7:3 ratio.Lesions were delineated layer by layer on high-resolution T2WI.Least absolute shrinkage and selection operator regression was applied to screen for radiomic features.Radiomics and clinical models were constructed using the multilayer perceptron(MLP)algorithm.These radiomic features and clinically relevant variables(selected based on a significance level of P<0.05 in the training set)were used to construct radiomics-clinical models.The performance of the three models(clinical,radiomic,and radiomic-clinical model)were evaluated using the area under the curve(AUC),calibration curve and decision curve analysis(DCA).RESULTS After feature selection,eight radiomic features were retained from the initial 1781 features to construct the radiomic model.Eight different classifiers,including logistic regression,support vector machine,k-nearest neighbours,random forest,extreme trees,extreme gradient boosting,light gradient boosting machine,and MLP,were used to construct the model,with MLP demonstrating the best diagnostic performance.The AUC of the radiomic-clinical model was 0.862(95%CI:0.796-0.927)in the training cohort and 0.761(95%CI:0.635-0.887)in the validation cohort.The AUC for the radiomic model was 0.796(95%CI:0.723-0.869)in the training cohort and 0.735(95%CI:0.604-0.866)in the validation cohort.The clinical model achieved an AUC of 0.751(95%CI:0.661-0.842)in the training cohort and 0.676(95%CI:0.525-0.827)in the validation cohort.All three models demonstrated good accuracy.In the training cohort,the AUC of the radiomic-clinical model was significantly greater than that of the clinical model(P=0.005)and the radiomic model(P=0.016).DCA confirmed the clinical practicality of incorporating radiomic features into the diagnostic process.CONCLUSION In this study,we successfully developed and validated a T2WI-based machine learning model as an auxiliary tool for the preoperative differentiation between well/moderately and poorly differentiated CRC.This novel approach may assist clinicians in personalizing treatment strategies for patients and improving treatment efficacy. 展开更多
关键词 Radiomics Colorectal cancer differentiation grade Machine learning T2-weighted imaging
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RPLP0/TBP are the most stable reference genes for human dental pulp stem cells under osteogenic differentiation 被引量:1
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作者 Daniel B Ferreira Leticia M Gasparoni +1 位作者 Cristiane F Bronzeri Katiucia B S Paiva 《World Journal of Stem Cells》 SCIE 2024年第6期656-669,共14页
BACKGROUND Validation of the reference gene(RG)stability during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data normalisation.Commonly,in an unreliable way,... BACKGROUND Validation of the reference gene(RG)stability during experimental analyses is essential for correct quantitative real-time polymerase chain reaction(RT-qPCR)data normalisation.Commonly,in an unreliable way,several studies use genes involved in essential cellular functions[glyceraldehyde-3-phosphate dehydro-genase(GAPDH),18S rRNA,andβ-actin]without paying attention to whether they are suitable for such experimental conditions or the reason for choosing such genes.Furthermore,such studies use only one gene when Minimum Information for Publication of Quantitative Real-Time PCR Experiments guidelines recom-mend two or more genes.It impacts the credibility of these studies and causes dis-tortions in the gene expression findings.For tissue engineering,the accuracy of gene expression drives the best experimental or therapeutical approaches.We cultivated DPSCs under two conditions:Undifferentiated and osteogenic dif-ferentiation,both for 35 d.We evaluated the gene expression of 10 candidates for RGs[ribosomal protein,large,P0(RPLP0),TATA-binding protein(TBP),GAPDH,actin beta(ACTB),tubulin(TUB),aminolevulinic acid synthase 1(ALAS1),tyro-sine 3-monooxygenase/tryptophan 5-monooxygenase activation protein,zeta(YWHAZ),eukaryotic translational elongation factor 1 alpha(EF1a),succinate dehydrogenase complex,subunit A,flavoprotein(SDHA),and beta-2-micro-globulin(B2M)]every 7 d(1,7,14,21,28,and 35 d)by RT-qPCR.The data were analysed by the four main algorithms,ΔCt method,geNorm,NormFinder,and BestKeeper and ranked by the RefFinder method.We subdivided the samples into eight subgroups.RESULTS All of the data sets from clonogenic and osteogenic samples were analysed using the RefFinder algorithm.The final ranking showed RPLP0/TBP as the two most stable RGs and TUB/B2M as the two least stable RGs.Either theΔCt method or NormFinder analysis showed TBP/RPLP0 as the two most stable genes.However,geNorm analysis showed RPLP0/EF1αin the first place.These algorithms’two least stable RGs were B2M/GAPDH.For BestKeeper,ALAS1 was ranked as the most stable RG,and SDHA as the least stable RG.The pair RPLP0/TBP was detected in most subgroups as the most stable RGs,following the RefFinfer ranking.CONCLUSION For the first time,we show that RPLP0/TBP are the most stable RGs,whereas TUB/B2M are unstable RGs for long-term osteogenic differentiation of human DPSCs in traditional monolayers. 展开更多
关键词 Dental pulp stem cells Reference gene Housekeeping gene Endogenous gene Osteogenic differentiation RefFinder
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Relative orbit determination algorithm of space targets with passive observation
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作者 DAI Chenchao QIANG Hongfu +2 位作者 ZHANG Degang HU Shaolei GONG Baichun 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期793-804,共12页
Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for ang... Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for angles-only observability was found by using cylindrical dynamics, however, the solution of orbit determination is still not provided. This study develops a relative orbit determination algorithm with the cylindrical dynamics based on differential evolution. Firstly, the relative motion dynamics and line-of-sight measurement model for nearcircular orbit are established in cylindrical coordinate system.Secondly, the observability is qualitatively analyzed by using the dynamics and measurement model where the unobservable geometry is found. Then, the angles-only relative orbit determination problem is modeled into an optimal searching frame and an improved differential evolution algorithm is introduced to solve the problem. Finally, the proposed algorithm is verified and tested by a set of numerical simulations in the context of highEarth and low-Earth cases. The results show that initial relative orbit determination(IROD) solution with an appropriate accuracy in a relative short span is achieved, which can be used to initialize the navigation filter. 展开更多
关键词 angles-only measurement relative orbit determination cylindrical coordinate differential evolution
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HNF-4α determines hepatic differentiation of human mesenchymal stem cells from bone marrow 被引量:9
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作者 Mong-Liang Chen Kuan-Der Lee +5 位作者 Huei-Chun Huang Yue-Lin Tsai Yi-Chieh Wu Tzer-Min Kuo Cheng-Po Hu Chungming Chang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第40期5092-5103,共12页
AIM: To investigate the differentiation status and key factors to facilitate hepatic differentiation of human bone-marrow-derived mesenchymal stem cells (MSCs). METHODS: Human MSCs derived from bone marrow were induce... AIM: To investigate the differentiation status and key factors to facilitate hepatic differentiation of human bone-marrow-derived mesenchymal stem cells (MSCs). METHODS: Human MSCs derived from bone marrow were induced into hepatocyte-like cells following a previously published protocol. The differentiation status of the hepatocyte-like cells was compared with various human hepatoma cell lines. Overexpression of hepatocyte nuclear factor (HNF)-4α was mediated by adenovirus infection of these hepatocyte-like cells. The expression of interesting genes was then examined by either re-verse transcription-polymerase chain reaction (RT-PCR) or real-time RT-PCR methods. RESULTS: Our results demonstrated that the differentiation status of hepatocyte-like cells induced from human MSCs was relatively similar to poorly differentiated human hepatoma cell lines. Interestingly, the HNF-4 isoform in induced MSCs and poorly differentiated human hepatoma cell lines was identified as HNF4γ instead of HNF-4α. Overexpression of HNF-4α in induced MSCs significantly enhanced the expression level of hepatic-specific genes, liver-enriched transcription factors, and cytochrome P450 (P450) genes. CONCLUSION: Overexpression of HNF-4α improves the hepatic differentiation of human MSCs from bone marrow and is a simple way of providing better cell sources for clinical applications. 展开更多
关键词 Bone marrow Cytochrome P450 genes differentiation of hepatocyte Hepatocyte nuclear factor 4 Human mesenchymal stem cells
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Determination of trace amounts of morphine in human plasma by anodic adsorptive stripping differential pulse voltammetry 被引量:3
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作者 Ali Niazi Ateesa Yazdanipour 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第4期465-468,共4页
New adsorptive anodic differential pulse stripping voltammetry method for the direct determination of morphine at trace levels in human plasma of addicts is proposed.The procedure involves an adsorptive accumulation o... New adsorptive anodic differential pulse stripping voltammetry method for the direct determination of morphine at trace levels in human plasma of addicts is proposed.The procedure involves an adsorptive accumulation of morphine on a HMDE,followed by oxidation of adsorbed morphine by voltammetry scan using differential pulse modulation.The optimum conditions for the analysis of morphine are pH 10.5,Eacc of -100 mV(vs.Ag/AgCl),and tacc of 120 s.The peak current is proportional to the concentration of morphine,and a Linear calibration graph is obtained at 0.01-3.10μg mL^-1.A relative standard deviation of 1.06%(n=5)was obtained,and the limit of detection was 3 ng mL^-1.The capabiLity of the method for the analysis of real samples was evaluated by the determination of morphine in spiked human plasma and addicts human plasma with satisfactory results. 展开更多
关键词 MORPHINE Adsorptive differential pulse voltammetry Human plasma
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A Dual Wavelength Differential First Derivative Spectrophotometric Method for Identification and Determination of Carbon Monoxide Generated During the Microsomal Metabolism of Xenobiotics in vitro
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作者 徐宏祥 刘志强 《Journal of Chinese Pharmaceutical Sciences》 CAS 1997年第2期51-56,共6页
A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and... A dual wavelength differential first derivative spectrophotometric method has been developed to standardize the concentration of a saturated aqueous solution of carbon monoxide (CO) as the standard and to identify and to determine CO formed during the microsomal metabolism of xenobiotics in vitro. The method can significantly eliminate the background interference in the assay media and increase the quantitative accuracy and the sensitivity. There is a good linear relationship between CO concentration in the range of 2~10 μmol·L 1 CO and the distance D between the first derivative peak at 415 nm amd valley at 426 nm with r=0.9999(n=5),the regression equation being C (mmol·L 1 )=17.6D 0.4, the detection limit lower than 0.1 μmol·L 1 CO. The average recoveries of CO from the assay system and the sample were 102.1%, RSD=2.9% (n=7) and 79.7%, RSD=6.8% (n=12),respectively. The RSD of within day was 4.4%(n=18),and the RSD of day to day was 6.1%(n=16). By this method, four trihaloanilines and one trihalobenzene were tested, the results showed that only 2,4,5 trifluoroaniline could be converted to CO by the incubation with rat hepatic microsomes, NADPH and oxygen, the ability of phenobarbital or dexamethasone to induce rat hepatic microsomes to catalyze CO formation was 3 or 8 times higher than that of the control. 展开更多
关键词 Dual wavelength differential first derivative spectrophotometry Carbon monoxide Trifluoroaniline Drug metabolism Hepatic microsomes Cytochrome P 450
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Sex Determination in Homo sapiens as a Multi-Step Process: Potential for Development of Variants and Sex Differences in Disease Risk
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作者 David A. Hart 《Journal of Biomedical Science and Engineering》 2024年第1期13-34,共22页
Reproduction via cis-binary mechanisms appears to have evolved fairly early in the evolution of complex organisms, and a system committed to prior to evolution of humans. While the evolution of a chromosomal-specific ... Reproduction via cis-binary mechanisms appears to have evolved fairly early in the evolution of complex organisms, and a system committed to prior to evolution of humans. While the evolution of a chromosomal-specific approach has been a successful strategy for survival of a large variety of species including humans, the fidelity of sex determination leading to 100% cis-binary outcomes is not achieved in many species, with evidence for homosexual or bisexual behaviour evident in more than 1500 species. Thus, such outcomes indicates that sex determination is a multi-step process and not a single event, and as such, could lead to the appearance of variants during the process which developed much earlier than humans. Variants could arise either due to intrinsic variation in the steps of determination, or also be influenced by environmental factors of a biological or psychological nature. In contrast to homosexual variants which do not require interventions such as hormone therapy or surgery, expression of gender dysphoria, is more based in psychology, but also has biological underpinnings and can be influenced by such hormonal interventions and surgery. While the numbers of those with gender dysphoria is small (~0.6% - 1.0% of population), the attention given to this issue raises the possibility of biological and psychological environmental factors impacting the emergence of some of those expressing gender dysphoria. Furthermore, transitioning from male-to-female or female-to-male can have consequences regarding disease risks latter in life, including the appearance of autoimmune diseases. This review will attempt to review some of the evidence regarding sex determination, discuss why the system has potentially not been improved upon during evolution, how a potential role for sex chromosome function on neurodevelopment may be central to variation in humans, and how commitment to the current strategy is likely integrated into other sex-related events such as puberty, pregnancy, and menopause to ensure species survival. It will also discuss how variants in sex determination could contribute to sex differences in disease risk and how epigenetic modifications could play a role in such risk. . 展开更多
关键词 Sex determination Variant Development Fidelity of Sex determination Biological Sex determination Species Variation
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Determination of isolation layer thickness for undersea mine based on differential cubature solution to irregular Mindlin plate 被引量:14
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作者 PENG Kang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第3期708-719,共12页
The differential cubature solution to the problem of a Mindlin plate lying on the Winkler foundation with two simply supported edges and two clamped edges was derived.Discrete numerical technology and shape functions ... The differential cubature solution to the problem of a Mindlin plate lying on the Winkler foundation with two simply supported edges and two clamped edges was derived.Discrete numerical technology and shape functions were used to ensure that the solution is suitable to irregular shaped plates.Then,the mechanical model and the solution were employed to model the protection layer that isolates the mining stopes from sea water in Sanshandao gold mine,which is the first subsea mine of China.Furthermore,thickness optimizations for the protection layers above each stope were conducted based on the maximum principle stress criterion,and the linear relations between the best protection layer thickness and the stope area under different safety factors were regressed to guide the isolation design.The method presented in this work provides a practical way to quickly design the isolation layer thickness in subsea mining. 展开更多
关键词 subsea mine irregular Mindlin plate differential cubature method isolation layer protection layer thicknessoptimization
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