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191.
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   
192.
Vesicular trafficking plays a crucial role in protein localization and movement, signal transduction, and multiple developmental processes in eukaryotic cells. Vesicle fusion is the final and key step in vesicle-mediated trafficking and mainly relies on SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors), the regulators including SM (Sec1/Munc18) family proteins, Rab GTPases and exocyst subunits. Verticillium dahliae is a widespread soil fungus that causes disruptive vascular diseases on a wide range of plants. To date, no genes involved in vesicular fusion process have been identified and characterized in V. dahliae. The recent publication of the draft genome sequence of V. dahliae allowed us to conduct a genome-wide identification, phylogeny and expression profile of genes encoding vesicular fusion components. Using compared genomics and phylogenetic methods, we identified 44 genes encoding vesicle fusion components in the V. dahliae genome. According to the structural features of their encoded proteins, the 44 V. dahliae genes were classified into 22 SNAREs (6 Qa-, 4 Qb-, 6 Qc-, 1 Qbc- and 5 R-types), 4 SM family proteins, 10 Rab GTPases and 8 exocyst proteins. Based on phylogeny and motif constitution analysis, orthologs of vesicle fusion component in filamentous fungi were generally clustered together into the same subclasses with well-supported bootstrap values. Analysis of the expression profiles of these genes indicated that many of them are significantly differentially expressed during vegetative growth and microsclerotia formation in V. dahliae. The analysis show that many components of vesicle fusion are well conserved in filamentous fungi and indicate that vesicle fusion plays a critical role in microsclerotia formation of smoke tree wilt fungus V. dahliae. The genome-wide identification and expression analysis of components involved in vesicle fusion should facilitate research in this gene family and give new insights toward elucidating their functions in growth, development and pathogenesis of V. dahliae.  相似文献   
193.
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   
194.

Background

Tumor necrosis factor-α (TNF-α) 308 G/A gene polymorphism has been reported to be associated with susceptibility to silicosis. However, the relevant study results are still inconsistent.

Objective and Methods

A meta-analysis was performed in order to drive a more precise estimation of the relationship between TNF-α-308 G/A gene polymorphism and susceptibility to silicosis. Electronic databases were searched and nine separate studies were included. The pooled odds ratios (ORs) and the corresponding 95% confidence internal (CI) were calculated by a fixed effect model.

Results

A total of 1267 cases and 1214 controls were included. In the overall analysis, significantly increased silicosis risk was found (for GA+AA vs. GG OR=1.45, 95%CI: 1.20-1.760, P=1.58E4; for GA vs. GG: OR=1.53, 95%CI=1.25-1.86, P=3.11E5; for A allele vs. G allele: OR=1.27, 95%CI=1.08-1.50, P= 0.004). In the subgroup analysis, significantly increased silicosis risk was also found among Asians (for GA+AA vs. GG: OR=1.63, 95%CI=1.27-2.08, P=1.01E4), for GA vs. GG: OR=1.71, 95%CI=1.33-2.20, P=3.44E5), for A allele vs. G allele: OR=1.45, 95%CI=1.17-1.80, P=0.001). However, no significantly increased risk was found among non-Asians for all genetic models.

Conclusions

TNF-α-308 G/A polymorphism might lead to an increased risk of silicosis susceptibility, especially for Asians. However, further studies with large sample sizes should be conducted to confirm the association.  相似文献   
195.
196.
Hou  Jinyan  Su  Pengfei  Wang  Dacheng  Chen  Xue  Zhao  Weiwei  Wu  Lifang 《Plant Cell, Tissue and Organ Culture》2020,142(1):143-156

Sapium sebiferum Roxb. is a widespread and economically important multipurpose tree due to its high value in ornamental, and biodiesel production as well as medicine. A highly efficient in vitro plant regeneration system through direct shoot organogenesis was established for the first time from leaves and petioles of S. sebiferum. The results showed that plant growth regulators (PGRs), mechanical damage, explant orientation, explant source, and developmental stage had a strong influence on the in vitro morphogenesis of S. sebiferum. For shoot organogenesis from leaves, the highest adventitious shoot induction rate (96.67%) with 25.67 shoots per explant was obtained when mechanically damaged leaves (the first three leaf explants at the top, leaf #1–3) were cultured with the abaxial surface placed down on Murashige and Skoog (MS) medium containing 0.5 mg L?1 thidiazuron (TDZ). For in vitro morphogenesis of petioles, the combination of 1-naphthylacetic acid (NAA) and 6-benzylainopurine (6-BA) played a key role in cell fate determination. All of the in vitro petioles produced adventitious shoots on MS medium containing 1.0 mg L?1 6-BA and 0.1 mg L?1 NAA, while they produced green calli on medium fortified with 0.5 mg L?1 6-BA and 1.0 mg L?1 NAA. The shoots were subcultured in medium fortified with 0.5 mg L?1 6-BA and 0.1 mg L?1 NAA for multiplication and elongation. The elongated shoots successfully rooted on half-strength MS (1/2 MS) medium fortified with 0.5 mg L?1 indole-butyric acid (IBA) and 0.25 mg L?1 indole-3-acetic acid (IAA), and the regenerated plantlets successfully acclimatized with a survival rate of 92.56% in the greenhouse. The genetic fidelity of in vitro regenerated plants was evaluated using inter simple sequence repeat molecular markers. The in vitro regenerated plants were found to be the true to their mother plant. This study will be beneficial for the large-scale propagation as well as the genetic improvement of S. sebiferum.

  相似文献   
197.
The significance of actin-related protein 2/3 complex subunit 4 (ARPC4) expression in bladder cancer, and its potential role in the invasion and migration of bladder cancer cells, has yet to be determined. This study was to identify the correlation between ARPC4 and lymph node metastasis, and to determine the role of ARPC4 in the invasive migration of T24 bladder cancer cells. One hundred and ninety-eight bladder cancer tissues and 40 normal bladder and lymph node tissues were examined. Tissue microarrays were constructed and subjected to immunohistochemical stating for ARPC4. Multiple logistic analysis was used to determine risk factors associated with bladder cancer metastasis. ARPC4 expression in T24 bladder cancer cells was suppressed using small interfering RNA and changes in protein levels were determined by Western blot analysis. The proliferation of bladder cancer cells after knocking down of ARPC4 was determined by cell counting kit-8. The effects of ARPC4 knockdown on T24 cell invasion and migration was determined using transwell and wound healing assays. Immunofluorescence analysis was performed to examine changes in pseudopodia formation and actin cytoskeleton structure. The expression of ARPC4 was elevated in bladder cancer tissues than normal tissues (84.3% vs 27.5%, P < 0.001). The multivariate logistic analysis demonstrated that the level of ARPC4, as a risk factor, was correlated with lymphatic metastasis (P < 0.05). ARPC4 knockdown attenuated proliferation, migration, invasion, and pseudopodia formation in T24 cells. ARPC4 expression, as a risk factor, is associated with lymphatic metastasis and is upregulated in bladder cancer tissues in comparison with normal tissues. Inhibition of ARPC4 expression significantly attenuates the proliferation, migration, and invasion of bladder cancer cell, possibly due to defects in pseudopodia formation.  相似文献   
198.
The rare ginsenosides are recognized as the functionalized molecules after the oral administration of Panax ginseng and its products. The sources of rare ginsenosides are extremely limited because of low ginsenoside contents in wild plants, hindering their application in functional foods and drugs. We developed an effective combinatorial biotechnology approach including tissue culture, immobilization, and hydrolyzation methods. Rh2 and nine other rare ginsenosides were produced by methyl jasmonate-induced culture of adventitious roots in a 10 L bioreactor associated with enzymatic hydrolysis using six β-glycosidases and their combination with yields ranging from 5.54 to 32.66 mg L−1. The yield of Rh2 was furthermore increased by 7% by using immobilized BglPm and Bgp1 in optimized pH and temperature conditions, with the highest yield reaching 51.17 mg L−1 (17.06% of protopanaxadiol-type ginsenosides mixture). Our combinatorial biotechnology method provides a highly efficient approach to acquiring diverse rare ginsenosides, replacing direct extraction from Panax plants, and can also be used to supplement yeast cell factories.  相似文献   
199.
Microbial cell factories have been extensively engineered to produce free fatty acids (FFAs) as key components of crucial nutrients, soaps, industrial chemicals, and fuels. However, our ability to control the composition of microbially synthesized FFAs is still limited, particularly, for producing medium-chain fatty acids (MCFAs). This is mainly due to the lack of high-throughput approaches for FFA analysis to engineer enzymes with desirable product specificity. Here we report a mass spectrometry (MS)-based method for rapid profiling of MCFAs in Saccharomyces cerevisiae by using membrane lipids as a proxy. In particular, matrix-assisted laser desorption/ionization time-of-flight (MALDI-ToF) MS was used to detect shorter acyl chain phosphatidylcholines from membrane lipids and a higher m/z peak ratio at 730 and 758 was used as an indication for improved MCFA production. This colony-based method can be performed at a rate of ~2 s per sample, representing a substantial improvement over gas chromatography-MS (typically >30 min per sample) as the gold standard method for FFA detection. To demonstrate the power of this method, we performed site-saturation mutagenesis of the yeast fatty acid synthase and identified nine missense mutations that resulted in improved MCFA production relative to the wild-type strain. Colony-based MALDI-ToF MS screening provides an effective approach for engineering microbial fatty acid compositions in a high-throughput manner.  相似文献   
200.
Early weaning usually causes intestinal disorders, enteritis, and diarrhea in young animals and human infants. Astragalus polysaccharides (APS) possesses anti-inflammatory activity. To study the anti-inflammatory mechanisms of APS and its potential effects on intestinal health, we performed an RNA sequencing (RNA-seq) study in lipopolysaccharide (LPS)-stimulated porcine intestinal epithelial cells (IPEC-J2) in vitro. In addition, LPS-stimulated BALB/c mice were used to study the effects of APS on intestinal inflammation in vivo. The results from the RNA-seq analysis show that there were 107, 756, and 5 differentially expressed genes in the control versus LPS, LPS versus LPS+APS, and control versus LPS+APS comparison groups, respectively. The results of Kyoto Encyclopedia of Genes and Genomes enrichment analysis indicated that the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways play significant roles in the regulation of inflammatory factors and chemokine expression by APS. Further verification of the above two pathways by using western blot and immunofluorescence analysis revealed that the gene expression levels of the phosphorylated p38 MAPK, ERK1/2, and NF-κB p65 were inhibited by APS, while the expression of IκB-α protein was significantly increased (p < .05), indicating that APS inhibits the production of inflammatory factors and chemokines by the inhibition of activation of the MAPK and NF-κB inflammatory pathways induced by LPS stimulation. Animal experiments further demonstrated that prefeeding APS in BALB/c mice can alleviate the expression of the jejunal inflammatory factors interleukin 6 (IL-6), IL-Iβ, and tumor necrosis factor-α induced by LPS stimulation and improve jejunal villus morphology.  相似文献   
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