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Physical Blocking Neural Tube Closure Affects Radial Intercalation and Neural Crest Midline-directed Migration in Xenopus Dorsal Explants
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作者 石宇 赵树华 毛炳宇 《Zoological Research》 CAS CSCD 北大核心 2009年第6期639-644,共6页
Neural tube defects (NTDs) are severe congenital malformation diseases, which occur in 1 out of 1000 births in human. In Xenopus, several tissue movements are involved in the neural tube closure process. Immediately... Neural tube defects (NTDs) are severe congenital malformation diseases, which occur in 1 out of 1000 births in human. In Xenopus, several tissue movements are involved in the neural tube closure process. Immediately after the neural tube fusion, the neural crest cells get monopolar protrusion toward dorsal midline and migrate to form the roof of the neural tube. At the same time, radial intercalation takes place from the ventral neural tube and forces it to be single-layered. Here, we physically block the neural tube closure to test the cell movements and the following patterning in Xenopus laevis explants. The results show that the single-layered neural tube fails to form and the neural crest cells remain at the lateral regions in the explants with NTDs. However, the patterning of the neural tube is not affected as indicated by the normal expression of the preneural genes. These results indicate a requirement of the neural tube fusion for the radial intercalation and the dorsal midline directed neural crest migration, but not for the dorsal-ventral patterning of the neural tube. 展开更多
关键词 Xenopus laevis neural tube defect neural tube closure neural crest Morghogenesis Intercalation Dorsoventral patterning
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Application of GIS-Based Spatial Filtering Method for Neural Tube Defects Disease Mapping 被引量:1
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作者 CHI Wenxue WANG Jinfeng +2 位作者 LI Xinhu ZHENG Xiaoying LIAO Yilan 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期1125-1130,共6页
This study is to assess the prevalence rates spatial pattern of neural tube defects with geographic information system and spatial filtering technique. A total of 80 infants who diagnosed from neural tube defects in t... This study is to assess the prevalence rates spatial pattern of neural tube defects with geographic information system and spatial filtering technique. A total of 80 infants who diagnosed from neural tube defects in the area being studied between 1998 and 2001 were analyzed. Firstly, the geographic information system (GIS) software ArcGIS was used to map the crude prevalence rates. Secondly, the data were smoothed by the method of spatial filtering. We evaluated that the effect of changes in spatial filtering radius size was assessed by creating maps based on various filtering radius sizes. The 3 miles or larger filtering radius gives better section variability than the 2 and 2.5 miles or smaller ones. The maps produced by the spatial filtering technique indicate that prevalence rates in the villages in the southeastern region are to produce higher prevalence than that in the other regions. The smoothed maps based on Heshun County display a more adequate data representation than the raw prevalence rate map. 展开更多
关键词 birth defects neural tube defects neural tube defects (NTDs) geographic information system (GIS) spatial filtering China
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Effect of Exposure to Trace Elements in the Soil on the Prevalence of Neural Tube Defects in a High-Risk Area of China 被引量:9
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作者 HUANG Jing WU JiLei +4 位作者 LI TieJun SONG XinMing ZHANG BingZi ZHANG PingWen ZHENG XiaoYing 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2011年第2期94-101,共8页
Objective Our objective is to build a model that explains the association between the exposure to trace elements in the soil and the risk of neural tube defects. Methods We built a function with different parameters t... Objective Our objective is to build a model that explains the association between the exposure to trace elements in the soil and the risk of neural tube defects. Methods We built a function with different parameters to describe the effects of trace elements on neural tube defects. The association between neural tube defects and trace element levels was transformed into an optimization problem using the maximum likelihood method. Results Tin, lead, nickel, iron, copper, and aluminum had typical layered effects (dosage effects) on the prevalence of neural tube defects. Arsenic, selenium, zinc, strontium, and vanadium had no effect, and molybdenum had one threshold value that affected the prevalence of birth defects. Conclusion As an exploratory research work, our model can be used to determine the direction of the effect of the trace element content of cultivated soil on the risk of neural tube defects, which shows the clues by the dosage effect of their toxicological characteristics. Based on our findings, future biogeochemical research should focus on the direct effects of trace elements on human health. 展开更多
关键词 Trace element neural tube defects Risk factors identification Poisson model Maximum likelihood estimation
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Unusual Patterns of Neural Tube Defects in a High Risk Region of Northern China 被引量:4
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作者 GONG CHEN LI-JUN PEI +11 位作者 JIAN HUANG XIN-MING SONG LIANG-MING LIN XUE GU JIAN-XIN WU FANG WANG JI-LEI WU JIA-PENG CHEN JU-FEN LIU RUO-LEI XIN TING ZHANG XIAO-YING ZHENG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第4期340-344,共5页
Objective To study the prevalence of different types of neural tube defects (NTDs) in Luliang Prefecture, Shanxi province, where the prevalence of NTDs is unusually high and the correlation between NTDs prevalence a... Objective To study the prevalence of different types of neural tube defects (NTDs) in Luliang Prefecture, Shanxi province, where the prevalence of NTDs is unusually high and the correlation between NTDs prevalence and patterns. Methods A surveillance population-based birth defects was performed in Luliang Prefecture, Shanxi province. Results The results of our study showed that the prevalence of NTDs was 2-fold higher in Luliang Prefecture than in other areas of Shanxi province. Unusual patterns of NTDs were found, however, multiple NTDs were relatively common in Luliang Prefecture, accounting for over 13% of all NTDs cases in China. Conclusion The prevalence of NTDs is associated with its patterns. 展开更多
关键词 neural tube defects EPIDEMIOLOGY Geographic variation
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Advanced glycation end products induce neural tube defects through elevating oxidative stress in mice 被引量:6
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作者 Ru-Lin Li Wei-Wei Zhao Bing-Yan Gao 《Neural Regeneration Research》 SCIE CAS CSCD 2018年第8期1368-1374,共7页
Our previous study showed an association between advanced glycation end products (AGEs) and neural tube defects (NTDs). To understand the molecular mechanisms underlying the effect of AGEs on neural tube developme... Our previous study showed an association between advanced glycation end products (AGEs) and neural tube defects (NTDs). To understand the molecular mechanisms underlying the effect of AGEs on neural tube development, C57BL/6 female mice were fed for 4 weeks with com- mercial food containing 3% advanced glycation end product bovine serum albumin (AGE-BSA) or 3% bovine serum albumin (BSA) as a control. After mating mice, oxidative stress markers including malondialdehyde and H202 were measured at embryonic day 7.5 (E7.5) of ges- tation, and the level of intracellular reactive oxygen species (ROS) in embryonic cells was determined at E8.5. In addition to evaluating NTDs, an enzyme-linked immunosorbent assay was used to determine the effect of embryonic protein administration on the N-(carboxymethyl) lysine reactivity of acid and carboxyethyl lysine antibodies at E10.5. The results showed a remarkable increase in the incidence of NTDs at El0.5 in embryos of mice fed with AGE-BSA (no hyperglycemia) compared with control mice. Moreover, embryonic protein administration resulted in a noticeable increase in the reactivity of N-(carboxymethyl) lysine and N(ε)-(carboxyethyl) lysine antibodies. Malondialdehyde and H2O2 levels in embryonic cells were increased at E7.5, followed by increased intracellular ROS levels at E8.5. Vitamin E supplementation could partially recover these phenomena. Collectively, these results suggest that AGE-BSA could induce NTDs in the absence of hyperglycemia by an underlying mechanism that is at least partially associated with its capacity to increase embryonic oxidative stress levels. 展开更多
关键词 nerve regeneration neural tube defects advanced glycation end products diabetic embryopathy oxidative stress N-(carboxymethyl)lysine malondiadehyde N(ε)-(carboxyethyl) lysine EMBRYO H2O2 bovine serum albumin neural regeneration
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Cell cycle-related genes p57kip2, Cdk5 and Spin in the pathogenesis of neural tube defects 被引量:2
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作者 Xinjun Li Zhong Yang +5 位作者 Yi Zeng Hong Xu Hongli Li Yangyun Han Xiaodong Long Chao You 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第20期1863-1871,共9页
In the field of developmental neurobiology, accurate and ordered regulation of the cell cycle and apoptosis are crucial factors contributing to the normal formation of the neural tube. Preliminary studies identified s... In the field of developmental neurobiology, accurate and ordered regulation of the cell cycle and apoptosis are crucial factors contributing to the normal formation of the neural tube. Preliminary studies identified several genes involved in the development of neural tube defects. In this study, we established a model of developmental neural tube defects by administration of retinoic acid to pregnant rats. Gene chip hybridization analysis showed that genes related to the cell cycle and apoptosis, signal transduction, transcription and translation regulation, energy and metabolism, heat shock, and matrix and cytoskeletal proteins were all involved in the formation of developmental neural tube defects. Among these, cell cycle-related genes were predominant. Retinoic acid treat-ment caused differential expression of three cell cycle-related genes p57kip2, Cdk5 and Spin, the expression levels of which were downregulated by retinoic acid and upregulated during normal neural tube formation. The results of this study indicate that cell cycle-related genes play an im-portant role in the formation of neural tube defects. P57kip2, Cdk5 and Spin may be critical genes in the pathogenesis of neural tube defects. 展开更多
关键词 neural tube defects NEURULATION gene chip cell cycle retinoic acid regulatory factor neural de-velopment regeneration neural regeneration
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Methylmalonic Acid in Amniotic Fluid and Maternal Urine as a Marker for Neural Tube Defects 被引量:2
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作者 罗小平 张炼 +3 位作者 魏虹 刘皖君 王慕逖 宁琴 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2004年第2期166-169,共4页
To evaluate the implication of methymalonic acid (MMA) in the early diagnosis of neural tube defects (NTD), a quantitative assay for MMA was established by using gas chromatography-mass spectrometry with stable isoto... To evaluate the implication of methymalonic acid (MMA) in the early diagnosis of neural tube defects (NTD), a quantitative assay for MMA was established by using gas chromatography-mass spectrometry with stable isotope of MMA as an internal standard. Amniotic fluid and maternal urine MMA concentration, maternal serum folate, red blood cell folate and vitamin B 12 levels were measured in the middle term of NTD-affected and normal pregnancies. Amniotic fluid and maternal urine MMA concentrations in the middle term of NTD affected pregnancies (1.4±0.9 μmol/L, and 22.1±12.6 nmol/μmol creatinine) were significantly higher than that of normal pregnancies (1.0±0.4μmol/L, and 2.5±1.1 nmol/μmol creatinine). There was no significant difference between normal and NTD pregnancies for serum folate, red blood cell folate and vitamin B 12 levels. The results suggested that MMAs in amniotic fluid and maternal urine are sensitive markers for early diagnosis of NTD. Vitamin B 12 is an active cofactor involved in the remethylation of homocycteine and its deficiency is an independent risk factor for NTD. MMA is a specific and sensitive marker for intracellular vitamin B 12 deficiency. This study suggests that it is necessary to monitor the vitamin B 12 deficiency and advocates vitamin B 12 supplementation with folate prevention program. 展开更多
关键词 neural tube defects methymalonic acid vitamin B 12 folic acid
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Polymorphisms of the maternal Slug gene in fetal neural tube defects in a Chinese population 被引量:1
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作者 Li Guo Hong Zhao +6 位作者 Yuheng Pei Quanren He Wan-I Li Ting Zhang Xiaoying Zheng Ran Zhou Jun Xie 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第17期1342-1346,共5页
Several studies have demonstrated that Slug,which encodes a zinc finger of the Snail family of transcription factors,is a potential risk factor for neural tube defects.Neural tube defects tend to occur with a high rat... Several studies have demonstrated that Slug,which encodes a zinc finger of the Snail family of transcription factors,is a potential risk factor for neural tube defects.Neural tube defects tend to occur with a high rate in Shanxi province,China.The present case-control study investigated genotypic distributions and allele frequencies of Slug C1548A polymorphisms in DNA samples from59 women with a history of neural tube defect pregnancies and 73 controls during the same period from Shanxi Province,China.Results demonstrated that women with a history of neural tube defect pregnancies had significantly greater genotypic distributions of Slug AA genotypes and A allele frequencies compared with controls,and A allele Slug C1548A was a risk factor for neural tube defects(odds ratio = 3.444;95% confidence interval;2.021-5.868,P 〈 0.05).Three-dimensional structure prediction revealed that Slug C1548A resulted in transition of aspartic acid into glutamate at position 119.This indicated that these mutations could lead to damaged protein structure and function.These findings suggest that Slug C1548A gene polymorphism is closely related to neural tube defects in a population of Han Chinese origin from Shanxi Province,China 展开更多
关键词 neural tube defects SLUG single nucleotide polymorphisms protein modeling
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An epidemiologic study of mitochondrial membrane transporter protein gene polymorphism and risk factors for neural tube defects in Shanxi, China 被引量:1
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作者 Zhizhen Liu Jun Xie +4 位作者 Tian'e Luo Tao Zhang Xia Zhao Hong Zhao Peizhen Li 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第6期463-469,共7页
The present study involved a questionnaire survey of 156 mothers that gave birth to children with neural tube defects or had a history of pregnancy resulting in children with neural tube defects (case group) and 156... The present study involved a questionnaire survey of 156 mothers that gave birth to children with neural tube defects or had a history of pregnancy resulting in children with neural tube defects (case group) and 156 control mothers with concurrent healthy children (control group) as well as detection of mitochondrial membrane transporter protein gene [uncoupling protein 2 (UCP2)] polymorphism. The maternal UCP2 3' untranslated region (UTR) D/D genotype and D allele frequency were significantly higher in the case group compared with the control group (odds ratio (OR) 3.233; 95% confidence interval (C/) 1.103 9.476; P= 0.040; OR: 3.484; 95% CI: for neural tube defects 2.109 5.753; P 〈 0.001). Univariate and multivariate logistic regression analysis of risk factors for neural tube defects showed that a matemal UCP2 3' UTR D/D genotype was negatively interacted with the mothers' consumption of frequent fresh fruit and vegetables (S = 0.007), positively interacted with the mothers' frequency of germinated potato consumption (S = 2.15) and positively interacted with the mothers' body mass index (S = 3.50). These findings suggest that maternal UCP2 3' UTR gene polymorphism, pregnancy time, consumption of germinated potatoes and body mass index are associated with an increased risk for neural tube defects in children from mothers living in Shanxi province, China. Moreover, there is an apparent gene-environment interaction involved in the development of neural tube defects in offspring. 展开更多
关键词 neural tube defects uncoupling protein 2 genetic polymorphisms risk factors INTERACTION
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Bayesian mapping of neural tube defects prevalence in Heshun County, Shanxi Province, China during 1998~2001 被引量:2
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作者 CHI Wen-xue WANG Jin-feng +2 位作者 LI Xin-hu ZHENG Xiao-ying LIAO Yi-lan 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第6期921-925,共5页
Objective: To estimate the prevalence rates of neural tube defects (NTDs) in Heshun County, Shanxi Province, China by Bayesian smoothing technique. Methods: A total of 80 infants in the study area who were diagnosed w... Objective: To estimate the prevalence rates of neural tube defects (NTDs) in Heshun County, Shanxi Province, China by Bayesian smoothing technique. Methods: A total of 80 infants in the study area who were diagnosed with NTDs were analyzed. Two mapping techniques were then used. Firstly, the GIS software ArcGIS was used to map the crude prevalence rates. Secondly, the data were smoothed by the method of empirical Bayes estimation. Results: The classical statistical approach produced an extremely dishomogeneous map, while the Bayesian map was much smoother and more interpretable. The maps produced by the Bayesian technique indicate the tendency of villages in the southeastern region to produce higher prevalence or risk values. Conclusions: The Bayesian smoothing technique addresses the issue of heterogeneity in the population at risk and it is therefore recommended for use in explorative mapping of birth defects. This approach provides procedures to identify spatial health risk levels and assists in generating hypothesis that will be investigated in further detail. 展开更多
关键词 Birth defects neural tube defects (NTDs) Disease map Spatial analysis Bayesian smoothing China
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Visualization of bHLH transcription factor interactions in living mammalian cell nuclei and developing chicken neural tube by FRET 被引量:1
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作者 Chen Wang Wei Bian +3 位作者 Caihong Xia Ting Zhang Francois Guillemot Naihe Jing 《Cell Research》 SCIE CAS CSCD 2006年第6期585-598,共14页
Members of the basic helix-loop-helix (bHLH) gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer (FRET) is used to monitor b... Members of the basic helix-loop-helix (bHLH) gene family play important roles in vertebrate neurogenesis. In this study, confocal microscopy-based fluorescence resonance energy transfer (FRET) is used to monitor bHLH protein-protein interactions under various physiological conditions. Tissue-specific bHLH activators, NeuroD 1, Mash 1, Neurogenin 1 (Ngn 1), Neurogenin2 (Ngn2), and ubiquitous expressed E47 protein are tagged with enhanced yellow fluorescence protein (EYFP) and enhanced cyan fluorescence protein (ECFP), respectively. The subcellular localization and mobility ofbHLH fusion proteins are examined in HEK293 cells. By transient transfection and in ovo electroporation, four pairs of tissue-specific bHLH activators and E47 protein are over-expressed in HEK293 cells and developing chick embryo neural tube. With the acceptor photobleaching method, FRET could be detected between these bHLH protein pairs in the nuclei of transfected cells and developing neural tubes. Mashl/E47 and Ngn2/E47 FRET pairs show higher FRET efficiencies in the medial and the lateral half of chick embryo neural tube, respectively. It suggests that these bHLH protein pairs formed functional DNA-protein complexes with regulatory elements of their downstream target genes in the specific regions. This work will help one understand the behaviours of bHLH factors in vivo. 展开更多
关键词 BHLH confocal microscopy chick embryo neural tube FRET in ovo electroporation photobleach
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Retinoic acid induction of genes associated with neural tube developmental defects
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作者 Xinjun Li Zhong Yang +5 位作者 Yi Zeng Hong Xu Hongli Li Yangyun Han Xiaodong Long ,Chao You 《Neural Regeneration Research》 SCIE CAS CSCD 2010年第21期1629-1633,共5页
To date, little information has been available regarding genes involved in the regulation of embryonic cell development, which participate in retinoic acid-induced neural tube defects in mice. Previous studies have re... To date, little information has been available regarding genes involved in the regulation of embryonic cell development, which participate in retinoic acid-induced neural tube defects in mice. Previous studies have revealed seven differentially expressed genes involved in neural tube developmental defects. However, gene expression and regulation is a complex process. Therefore, gene expression differences between normal and defective neural tubes at 9.5 and 10.5 days were compared. A total of eight differentially expressed genes exhibited coincident alterations at embryonic 9.5 and 10.5 days. In mice with retinoic acid-induced neural tube defects, NeK7, IGFBP5 ZW10, Csf3r, PSMC6, Cdk5, and Rbl expressions were downregulated, but Apoa-4 expression was upregulated. These results were confirmed by Northern blot hybridization. Results suggested that NeK7, IGFBP5, ZW10, Csf3r, PSMC6, Cdk5, Rb1, and Apoa-4 are important regulatory factors involved in neural tube defects. 展开更多
关键词 neural tube defects neurula DNA microarray retinoic acid regulatory factor
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Gene expression in retinoic acid-induced neural tube defects A cDNA microarray analysis
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作者 Xiaodong Long Zhong Yang +3 位作者 Yi Zeng Hongli Li Yangyun Han Chao You 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第3期165-170,共6页
BACKGROUND: Neural tube defects can be induced by abnormal factors in vivo or in vitro during development. However, the molecular mechanisms of neural tube defect induction, and the related gene expression and regula... BACKGROUND: Neural tube defects can be induced by abnormal factors in vivo or in vitro during development. However, the molecular mechanisms of neural tube defect induction, and the related gene expression and regulation are still unknown. OBJECTIVE: To compare the differences in gene expression between normal embryos and those with neural tube defects. DESIGN, TIME AND SETTING: A neural development study was performed at the Department of Neurobiology, Third Military Medical University of Chinese PLA between January 2006 and October 2007. MATERIALS: Among 120 adult Kunming mice, 60 pregnant mice were randomly and evenly divided into a retinoic acid group (n = 30) and a normal control group (n =30). The retinoic acid was produced by Sigma, USA, the gene microarray by the Amersham Pharmacia Company, Hong Kong, and the gene sequence was provided by the Incyte database, USA. METHODS: Retinoic acid was administered to prepare models of neural tube defects, and corn oil was similarly administered to the normal control group. Total RNA was extracted from embryonic tissue of the two groups using a Trizol kit, and a cDNA microarray containing 1 100 known genes was used to compare differences in gene expression between the normal control group and the retinoic acid group on embryonic (E) day 10.5 and 11.5. Several differentially expressed genes were randomly selected from the two groups for Northern blotting, to verify the results of the cDNA microarray. MAIN OUTCOME MEASURES: Morphological changes and differential gene expression between the normal control group and the retinoic acid group. RESULTS: Anatomical microscopy demonstrated that an intact closure of the brain was formed in the normal mouse embryos by days E10.5 and E11.5. The cerebral appearance was full and smooth, and the surface of the spine was intact. However, in the retinoic acid group on days E10.5 and E11.5, there were more dead embryos. Morphological malformations typically included non-closure at the top of the cranium and abnormal changes of the metencephalon and face. cDNA microarray analysis suggested that the changes in expression of seven different genes were similar on both days E10.5 and E11.5. These were downregulation of NekT, Igfbp5, Zw10, Csf3r, Psmc6 and Rb 1, and upregulation of Apoa-4. This study also indicated that Cdk5 expression was downregulated in the retinoic acid group on day E11.5. The results of the cDNA microarray analysis were partly confirmed by Northern blotting. CONCLUSION: Cdk5, Nek7, Igfbp5, Zw10, Csf3r, Psmc6, Rb1 and Apoa-4 may be key factors in retinoic acid-induced neural tube defects. 展开更多
关键词 neural tube defects NEURULATION cDNA microarray retinoic acid
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Apoptotic gene expression in the neural tube during early human embryonic development
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作者 Guifang Chen Tiandong Li +2 位作者 Peipei Ding Ping Yang Xiao Zhang 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第1期55-59,共5页
Neural tube development comprises neural induction, neural epithelial cell proliferation, and apoptosis, as well as migration of nerve cells. Too much or too little apoptosis leads to abnormal nervous system developme... Neural tube development comprises neural induction, neural epithelial cell proliferation, and apoptosis, as well as migration of nerve cells. Too much or too little apoptosis leads to abnormal nervous system development. The present study analyzed expression and distribution of apoptotic-related factors, including Fas, FasL, and caspase-3, during human embryonic neural tube development. Experimental results showed that increased caspase-3 expression promoted neural apoptosis via a mitochondrial-mediated intrinsic pathway at 4 weeks during early human embryonic neural tube development. Subsequently, Fas and FasL expression increased during embryonic development. The results suggest that neural cells influence neural apoptosis through synergistic effects of extrinsic pathways. Therefore, neural apoptosis during the early period of neural tube development in the human embryo might be regulated by the death receptor induced apoptotic extrinsic pathways. 展开更多
关键词 apoptosis CASPASE-3 FAS human embryo neural tube development quantitativereverse transcription polymerase chain reaction
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PSO/ACO Algorithm-based Risk Assessment of Human Neural Tube Defects in Heshun County,China
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作者 LIAO Yi Lan WANG Jin Feng +2 位作者 WU Ji Lei WANG Jiao Jiao ZHENG XiaoYing 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2012年第5期569-576,共8页
Abstract Objective To develop a new technique for assessing the risk of birth defects, which are a major cause of infant mortality and disability in many parts of the world. Methods The region of interest in this stud... Abstract Objective To develop a new technique for assessing the risk of birth defects, which are a major cause of infant mortality and disability in many parts of the world. Methods The region of interest in this study was Heshun County, the county in China with the highest rate of neural tube defects (NTDs). A hybrid particle swarm optimization/ant colony optimization (PSO/ACO) algorithm was used to quantify the probability of NTDs occurring at villages with no births. The hybrid PSO/ACO algorithm is a form of artificial intelligence adapted for hierarchical classification. It is a powerful technique for modeling complex problems involving impacts of causes. Results The algorithm was easy to apply, with the accuracy of the results being 69.5%+7.02% at the 95% confidence level. Conclusion The proposed method is simple to apply, has acceptable fault tolerance, and greatly enhances the accuracy of calculations. 展开更多
关键词 neural tube birth defects GIS PSO/ACO algorithm Hierarchical classification Risk map
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Study of A1298C MTHFR Gene Polymorphism as a Risk Factor for Neural Tube Defects in the Eastern Algerian Population
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作者 Amel Abbas Karima Sifi +1 位作者 Karima Benembarek Nourredine Abadi 《Open Journal of Genetics》 2021年第3期32-41,共10页
<b><span style="font-family:;" "="">Background:</span></b><span style="font-family:;" "=""> As C677T mutation, A1298C mutation in methyle... <b><span style="font-family:;" "="">Background:</span></b><span style="font-family:;" "=""> As C677T mutation, A1298C mutation in methylene tetrahydrofolate reductase (MTHFR) gene results in a decreased MTHFR activity but </span><span style="font-family:;" "="">to</span><span style="font-family:;" "=""> a less extent, it is known as a risk factor of predisposition to human neural tube defects (NTDs), in some populations. Our objective was therefore to study, for the first time in Algerian population, if A1298C polymorphism confer</span><span style="font-family:;" "="">s </span><span style="font-family:;" "="">risk for the occurrence of this abnormality. We have examined the distribution of the genotype and the allele frequencies of A1298C mutation, and also their influence on plasma homocysteine (Hcy) concentration. <b>Patients and Methods:</b> We studied this polymorphism in 38 mothers of NTD cases and 67 control individuals of an eastern Algerian population. The muta<span>tion was determined by polymerase chain reaction</span></span><span style="font-family:;" "="">-</span><span style="font-family:;" "="">restriction fragm</span><span style="font-family:;" "="">ent length polymorphism analysis (PCR/RFLP). Plasma homocysteine concentration was analyzed using an automated chemiluminescence method. <b>Results:</b> No signi?cant association could be observed between allele and genotypes frequencies of A1298C MTHFR gene polymorphism and NTDs risk. However, we could observe that A1298C polymorphism affects homocysteine metabolism in mothers of NTD cases leading to homocysteine concentration values higher in AA genotype and lower in AC/CC genotypes (15.29</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">±</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">11.8 μmol/l <span>vs.<i> </i></span>8.63</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">±</span><span style="font-family:;" "=""> </span><span style="font-family:;" "="">3.83 μmol/l, <i>p</i> < 0.05). <b>Conclusion:</b> Data indicate that A1298C MTHFR gene polymorphism might be a risk factor by affecting homocysteine metabolism in mothers of Algerian children with NTDs.</span> 展开更多
关键词 Methylenetetrahydrofolate Reductase A1298C Polymorphism Homocyste-ine neural tube Defects
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Prevention of neural tube defects with folic acid: The Chinese experience 被引量:12
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作者 Ai-Guo Ren 《World Journal of Clinical Pediatrics》 2015年第3期41-44,共4页
Neural tube defects(NTDs) are a group of congenital malformations of the central nervous system that are caused by the closure failure of the embryonic neural tube by the 28 th day of conception. Anencephaly and spina... Neural tube defects(NTDs) are a group of congenital malformations of the central nervous system that are caused by the closure failure of the embryonic neural tube by the 28 th day of conception. Anencephaly and spina bifida are the two major subtypes. Fetuses with anencephaly are often stillborn or electively aborted due to prenatal diagnosis, or they die shortly after birth. Most infants with spina bifida are live-born and, with proper surgical treatment, can survive into adulthood. However, these children often have life-long physical disabilities. China has one of the highest prevalence of NTDs in the world. Inadequate dietary folate intake is believed to be the main cause of the cluster. Unlike many other countries that use staple fortification with folic acid as the public health strategy to prevent NTDs, the Chinese government provides all women who have a rural household registration and who plan to become pregnant with folic acid supplements, free of charge, through a nation-wide program started in 2009. Two to three years after the initiation of the program, the folic acid supplementation rate increased to 85% in the areas of the highest NTD prevalence. The mean plasma folate level of women during early and mid-pregnancy doubled the level before the program was introduced. However, most women began taking folic acid supplements when they knew that they were pregnant. This is too late for the protection of the embryonic neural tube. In a postprogram survey of the women who reported folic acid supplementation, less than a quarter of the women began taking supplements prior to pregnancy, indicating that the remaining three quarters of the fetuses remained unprotected during the time of neural tube formation. Therefore, staple food fortification with folic acid should be considered as a priority in the prevention of NTDs. 展开更多
关键词 neural tube DEFECTS Folic ACID Folate Supplementation FORTIFICATION
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Frontiers in research on maternal diabetes-induced neural tube defects:Past,present and future 被引量:2
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作者 Shyamasundar Sukanya Boon Huat Bay +1 位作者 Samuel Sam Wah Tay S Thameem Dheen 《World Journal of Diabetes》 SCIE CAS 2012年第12期196-200,共5页
Diabetes mellitus rightly regarded as a silent-epidemic is continually on the rise and estimated to have a global prevalence of 6.4 % as of 2010.Diabetes during pregnancy is a well known risk factor for congenital ano... Diabetes mellitus rightly regarded as a silent-epidemic is continually on the rise and estimated to have a global prevalence of 6.4 % as of 2010.Diabetes during pregnancy is a well known risk factor for congenital anomalies in various organ systems that contribute to neonatal mortality,including cardiovascular,gastrointestinal,genitourinary and neurological systems,among which the neural tube defects are frequently reported.Over the last two to three decades,several groups around the world have focussed on identifying the molecular cues and cellular changes resulting in altered gene expression and the morphological defects and in diabetic pregnancy.In recent years,the focus has gradually shifted to looking at pre-programmed changes and activation of epigenetic mechanisms that cause altered gene expression.While several theories such as oxidative stress,hypoxia,and apoptosis triggered due to hyperglycemic conditions have been proposed and proven for being the cause for these defects,the exact mechanism or the link between how high glucose can alter gene expression/transcriptome and activate epigenetic mechanisms is largely unknown.Although preconceptual control of diabetes,(i.e.,managing glu-cose levels during pregnancy),and in utero therapies has been proposed as an effective solution for managing diabetes during pregnancy,the impact that a fluctuating glycemic index can have on foetal development has not been evaluated in detail.A tight glycemic control started before pregnancy has shown to reduce the incidence of congenital abnormalities in diabetic mothers.On the other hand,a tight glycemic control after organogenesis and embryogenesis have begun may prove insufficient to prevent or reverse the onset of congenital defects.The importance of determining the extent to which glycemic levels in diabetic mothers should be regulated is critical as foetal hypoglycemia has also been shown to be teratogenic.Finally,the major question remaining is if this whole issue is negligible and not worthy of investigation as the efficient management of diabetes during pregnancy is well in place in many countries. 展开更多
关键词 Maternal diabetes CONGENITAL anomalies neural tube defects HYPERGLYCEMIA Hypoxia Oxidative stress neural stem cells EPIGENETICS EPIGENOME
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Pattern and Management of Neural Tube Defect in Cameroon 被引量:1
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作者 Mathieu Motah Mireille Moumi +2 位作者 Aurélien Ndoumbe Clerence Ntieafac Vincent De Paul Djienctheu 《Open Journal of Modern Neurosurgery》 2017年第3期87-102,共16页
Objectives: The aim of study was to determine the pattern and management of neural tube defects (NTD). Methodology: It was a hospital based descriptive cross-sectional retrospective study on patients who consulted and... Objectives: The aim of study was to determine the pattern and management of neural tube defects (NTD). Methodology: It was a hospital based descriptive cross-sectional retrospective study on patients who consulted and/or were admitted at the Douala General hospital for neural tube defects from January 2005 to April 2015. Results: A total of forty-nine (49) patients were enrolled. Males constituted 59.8% and females 40.2% giving a sex ratio of 1.5 in favour of males. Most of the parents of the patients (71.5%) had a low socio-economic status. Myelomeningocele was the most common type (80.4%) followed by 17.4% cases of meningocele and 2.2% cases of lipomeningocele. Three cases (3) of encephaloceles were seen during this period. The commonest site of these defects was the lumbosacral region (47.8%). Other sites included lumbar (19;41.3%), sacral (3;6.5%) and thoracolumbar (2;4.3%) ones. About half of the patients (24;48.9%) presented with ruptured lesions. Hydrocephalus was also recorded in 65.3% of patients. Talipes equinovarus and talipes calcaneovalgus were the most common associated orthopedic birth defects found. Surgical closure was done for 44 (89.9%) patients. Ventriculoperitoneal shunting was done in 78.1% of those who presented with hydrocephalus. Post-operative complications were more frequent in patients with ruptured lesions (P = 0.001). The most common post-operative complications were wound infections (22;44.9%) and wound dehiscence (20;40.8%). Conclusion: Lumbosacral Myelomeningocele was the most common type of NTD in our region. Low socio-economic status was a common risk factor. 展开更多
关键词 neural tube DEFECTS MYELOMENINGOCELE Cameroon
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Association of RFC-1 80A→G and MTHFR 677C→T polymorphisms with neural tube defects in Ukrainian population 被引量:2
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作者 V.N.Zaporozhan V.G.Marrichereda +1 位作者 P.Cavalli O.N.Kulish 《中国现代医学杂志》 CAS CSCD 北大核心 2014年第13期1-7,共7页
【Objective】To evaluate the roles of 80A→G polymorphism of RFC-1 gene encoding the reduced folate carrier protein and 677C→T polymorphism of 5,10-methylenetetrahydrofolate reductase gene(MTHFR)in neural tube defect... 【Objective】To evaluate the roles of 80A→G polymorphism of RFC-1 gene encoding the reduced folate carrier protein and 677C→T polymorphism of 5,10-methylenetetrahydrofolate reductase gene(MTHFR)in neural tube defects(NTD)risk in Ukrainian population.【Methods】The folate status,homocysteine levels and genotypes were assessed in 42 mothers of fetuses with spina bifida,anencephaly and encephalocele with the age of 19-40 years.Serum folate and plasma homocysteine levels were estimated using chemiluminescence technology.DNA was isolated from peripheral leukocytes obtained from blood using standard procedures.The presence of the RFC-1 80A→G polymorphism was investigated using polymerase chain reaction(PCR).Real time PCR was used to detect the presence of the 677C→T mutation in the MTHFR gene.【Results】Genotype frequencies for RFC-1 80A→G in NTD group were:homozygous wild type in 9(21.4%),heterozygous type in16(38.1%)women;17(40.5%)women surveyed were found homozygous for the mutant allele genotype of RFC-1(GG).Homozygous for the indicated mutation was found in 57.1%of women with fetal anencephaly in the past history and 29.6%of women with spina bifida fetuses.Allelic frequency in this group of women for allele A was 40.5%(34),for allele G was 59.5%(50).Among women with 80A/A genotype of RFC-1 gene reduced levels of serum folic acid were noticed only in 6(35.5%),but hyperhomocysteinemia was found in 10(58.8%)women.【Conclusion】80G→A polymorphism of RFC-1 gene is a potential genetic factor in the formation of fetus NTD in women of South Ukraine. 展开更多
关键词 甲状腺 病理分析 肿瘤 临床分析
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