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901.
MicroRNAs (miRNAs), approximately 22-nucleotide non-coding RNA molecules, regulate a variety of pivotal physiological or pathological processes, including embryonic development and tumorigenesis. To obtain comprehensive expression profiles of miRNAs in human embryos, we characterized miRNA expression in weeks 4-6 of human embryonic development using miRNA microarrays and identified 50 human-embryo-specific miRNAs (HES-miRNAs). Furthermore, we selected three non-conserved or primate-specific miRNAs, hsa-miR-638, -720, and -1280, and examined their expression levels in various normal and tumor tissues. The results show that expression of most miRNAs is extremely low during early human embryonic development. In addition, the expression of some non-conserved or primate-specific miRNAs is significantly different between tumor and the corresponding normal tissue samples, suggesting that the miRNAs are closely related to the pathological processes of various tumors. This study presents the first comprehensive overview of miRNA expression during human embryonic development and offers immediate evidence of the relationship between human early embryonic development and tumorigenesis. 相似文献
902.
High throughput sequencing of 16S rRNA gene leads us into a deeper understanding on bacterial diversity for complex environmental samples, but introduces blurring due to the relatively low taxonomic capability of short read. For wastewater treatment plant, only those functional bacterial genera categorized as nutrient remediators, bulk/foaming species, and potential pathogens are significant to biological wastewater treatment and environmental impacts. Precise taxonomic assignment of these bacteria at least at genus level is important for microbial ecological research and routine wastewater treatment monitoring. Therefore, the focus of this study was to evaluate the taxonomic precisions of different ribosomal RNA (rRNA) gene hypervariable regions generated from a mix activated sludge sample. In addition, three commonly used classification methods including RDP Classifier, BLAST-based best-hit annotation, and the lowest common ancestor annotation by MEGAN were evaluated by comparing their consistency. Under an unsupervised way, analysis of consistency among different classification methods suggests there are no hypervariable regions with good taxonomic coverage for all genera. Taxonomic assignment based on certain regions of the 16S rRNA genes, e.g. the V1&V2 regions – provide fairly consistent taxonomic assignment for a relatively wide range of genera. Hence, it is recommended to use these regions for studying functional groups in activated sludge. Moreover, the inconsistency among methods also demonstrated that a specific method might not be suitable for identification of some bacterial genera using certain 16S rRNA gene regions. As a general rule, drawing conclusions based only on one sequencing region and one classification method should be avoided due to the potential false negative results. 相似文献
903.
Background
Elevated plasma levels of lipoprotein(a) (Lp(a)) and a higher degree of coronary artery calcification (CAC) are both considered to be risk factors for atherosclerosis. However, previous studies have demonstrated that the relationship between Lp(a) levels and the degree of CAC indicates significant heterogeneity that may be due to varying ethnicities. The purpose of this study was to examine the predictive power of Lp(a) for CAC as measured by multidetector computed tomography (MDCT) in the Han ethnic group of China.Methods
A total of 1082 subjects were recruited in this study. The patients were divided into four groups: patients without hypertension or diabetes were group 1, patients with hypertension were group 2, patients with diabetes were group 3 and patients with both hypertension and diabetes were group 4. CAC score (CACs), lipid profiles (Lp(a), LDL, HDL, TG, TC), HbA1C, glucose, personal health history and body morphology were measured in all participants. The predictive power of Lp(a) for calcified atherosclerotic plaque was determined by correlations and ordinal logistic regression.Results
There was no significant difference in the CACs between group 2 and group 3 (z = 1.790, p = 0.736), and there were significant differences among the other groups. However, there was no significant difference in the total Lp(a) among the 4 groups (χ2 = 0.649, p = 0.885). Only In group 1, Lp(a) was a statistically significant predictor of the presence of calcified coronary plaque using ordinal logistic regression.Conclusions
Levels of Lp(a) positively correlate with CACs among Chinese Han people who are without diabetes and hypertension, suggesting that Lp(a) may be an important risk factor for the presence of calcified atheromas. 相似文献904.
Li Gao Hao Guo Nan Ye Yudi Bai Xin Liu Ping Yu Yang Xue Shufang Ma Kewen Wei Yan Jin Lingying Wen Kun Xuan 《PloS one》2013,8(6)
Congenital insensitivity to pain with anhidrosis (CIPA) is a rare inherited disorder of the peripheral nervous system resulting from mutations in neurotrophic tyrosine kinase receptor 1 gene (NTRK1), which encodes the high-affinity nerve growth factor receptor TRKA. Here, we investigated the oral and craniofacial manifestations of a Chinese patient affected by autosomal-recessive CIPA and identified compound heterozygosity in the NTRK1 gene. The affected boy has multisystemic disorder with lack of reaction to pain stimuli accompanied by self-mutilation behavior, the inability to sweat leading to defective thermoregulation, and mental retardation. Oral and craniofacial manifestations included a large number of missing teeth, nasal malformation, submucous cleft palate, severe soft tissue injuries, dental caries and malocclusion. Histopathological evaluation of the skin sample revealed severe peripheral nerve fiber loss as well as mild loss and absent innervation of sweat glands. Ultrastructural and morphometric studies of a shed tooth revealed dental abnormalities, including hypomineralization, dentin hypoplasia, cementogenesis defects and a dysplastic periodontal ligament. Genetic analysis revealed a compound heterozygosity- c.1561T>C and c.2057G>A in the NTRK1 gene. This report extends the spectrum of NTRK1 mutations observed in patients diagnosed with CIPA and provides additional insight for clinical and molecular diagnosis. 相似文献
905.
Guo Wenfang Li Gangqiang Wang Nan Yang Caifeng Zhao Yanan Peng Huakang Liu Dehu Chen Sanfeng 《Plant molecular biology》2020,102(4-5):553-567
Plant Molecular Biology - Overexpression of K2-NhaD in transgenic cotton resulted in phenotypes with strong salinity and drought tolerance in greenhouse and field experiments, increased expression... 相似文献
906.
Biological Trace Element Research - Diabetic peripheral neuropathy (DPN) is a common complication of diabetes mellitus, presented as a major teratogenic cause worldwide. This study discussed... 相似文献
907.
Wuxia Zhang Yihua Hu Jinzhong Zhao Yongpo Zhang Dongdong Guo Chunyan Gao Jinyou Duan Peng Li 《Glycoconjugate journal》2020,37(3):361-371
Radix Paeoniae Alba is widely used in Chinese traditional medicine to treat various diseases such as gastrointestinal disorders, immunomodulatory, cancer, and other diseases. In this paper, a novel acidic polysaccharide RPAPS purified from Radix Paeoniae Alba was evaluated for its structural features and potential of immunomodulatory and antioxidant activities. RPAPS (molecular weight: 1.0× 105 Da) was mainly composed of α-(1 → 4)-Glcp, α-Arap, α-Galp, α-Rhap, β-D-Glcp, α-(1 → 6)-linked Glcp and GalA. Immunological tests indicated that RPAPS could improve RAW264.7 phagocytic activity and LPS-induced splenocyte proliferation. For antioxidant activities, RPAPS showed reducing power and DPPH scavenging activity in dose dependent. Moreover, RPAPS could significantly protect the PC12 cells from H2O2 damage. These data implied polysaccharides RPAPS had the potential to be novel natural antioxidative and immunopotentiating agents for using in functional foods or medicine. 相似文献
908.
Ying Zou Yi-Na Wang Hong Ma Zhi-Hui He Yan Tang Liang Guo Yang Liu Meng Ding Shu-Wen Qian Qi-Qun Tang 《Journal of lipid research》2020,61(12):1589
Beiging of white adipose tissue (WAT) has beneficial effects on metabolism. Although it is known that beige adipocytes are active in lipid catabolism and thermogenesis, how they are regulated deserves more explorations. In this study, we demonstrate that stearoyl-CoA desaturase 1 (SCD1) in subcutaneous WAT (scWAT) responded to cold stimulation and was able to promote mobilization of triacylglycerol [TAG (triglyceride)]. In vitro studies showed that SCD1 promoted lipolysis in C3H10T1/2 white adipocytes. The lipolytic effect was contributed by one of SCD1’s products, oleic acid (OA). OA upregulated adipose TAG lipase and hormone-sensitive lipase expression. When SCD1 was overexpressed in the scWAT of mice, lipolysis was enhanced, and oxygen consumption and heat generation were increased. These effects were also demonstrated by the SCD1 knockdown experiments in mice. In conclusion, our study suggests that SCD1, known as an enzyme for lipid synthesis, plays a role in upregulating lipid mobilization through its desaturation product, OA. 相似文献
909.
910.
Dandan Wang Yulin Guo Xiaofei Long Yan Pan Dingjie Yang Rui Li Ye Lu Ying Chen Jisen Shi Jinhui Chen 《Phyton》2020,89(1):27-34
In order to study how exogenous hormones in C. lanceolata
(gymnosperm) regulate somatic embryogenesis, we measured the endogenous
phytohormones of two genotypes with different somatic embryogenesis
efficiency and found that an increase in endogenous concentrations of IAA and
ABA may be correlated to more efficient somatic embryogenesis. By applying
exogenous spermidine, we found that exogenous hormones may affect somatic
embryogenesis efficiency through affecting the endogenous phytohormone
content. Based on these results, further studies can be conducted whereby the
concentration of exogenous hormones or the levels of endogenous
phytohormones by molecular methods are regulated to promote somatic
embryogenesis. Our research may benefit the long-term economic output of the
forestry industry and lays the foundation to studying the molecular mechanism
that controls somatic embryogenesis efficiency. 相似文献