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Lyme disease, caused by Borrelia burgdorferi, is a focally endemic tick‐transmitted zoonotic infection. In this study, the major factors underlying synonymous codon‐related amino acid usage in the B. burgdorferi genome and bias in synonymous codon usage of the translation initiation region of coding sequences were analyzed. Additionally, adaptation of B. burgdorferi to several of its hosts was analyzed in the context of synonymous codon usage. Principal component analysis (PCA) revealed that nucleotide content at the third synonymous position of a codon influenced the synonymous codon usage pattern, but the strand‐specific factor did not influence the synonymous codon usage pattern of B. burgdorferi. In terms of the low GC content of B. burgdorferi coding sequences, the effective number of codons (ENC) showed a significant correlation with GC3 content (at the synonymous position). For the amino acid usage pattern for B. burgdorferi, PCA showed that the strand‐specific factor did not contribute to this pattern, while the properties (aromaticity and hydrophobicity) of the amino acids themselves showed strong correlations with this pattern. Under‐represented codons, which were frequently selected in the translation initiation region, possibly play roles in regulating gene expression in B. burgdorferi. In terms of co‐evolution and synonymous codon usage patterns, adaptation of B. burgdorferi to different intermediate hosts was apparent to different degrees, and the degree of adaptation of this spirochete to wild animals was stronger than that of humans or mice. [ABSTRACT FROM AUTHOR]

A high accuracy alternation direction implicit scheme ADI for solving the two-dimensional parabolic equations is presented and the scheme is absolutely stable and the truncation error is O( Τ² + h4). The experiments show the scheme is effective and advantage,and the theory is right by a numerical example. [ABSTRACT FROM AUTHOR]

The complete chloroplast (cp) genome of Aconitum austroyunnanense W. T. Wang, a rare and endangered medicinal plant endemic to southwestern China, was sequenced to be 155,818 bp in length, including two inverted repeat (IR, 26,128 bp) regions, one large single-copy region (LSC) and one small single-copy region (SSC) of 86,555 bp and 17,007 bp, respectively. The cp genome has 131 annotated genes, including 85 protein-coding genes, 37 tRNA genes, 8 rRNA genes, and a pseudogene (ycf1). The overall GC content of it is 38.1%. Phylogenetic analysis revealed that the cp genome of A. austroyunnanense is closely related to that of Aconitum hemsleyanum. [ABSTRACT FROM AUTHOR]

" Engineering Drawing autonomous learning platform " provides a completely independent, opening, interactive learning environment for the engineering drawing learners and enthusiasts. The platform focuses on " electronic classroom", is assisted with " electronic laboratory" and supported by " learning management system" . The platform integrates the functions of teaching, learning, practice, test, and judgment. It has many features, such as autonomy, assistant, reproducibility, opening, interactivity and so on. When the learners log in, the management system wilprovide study Yuidance accordinYto the reYistration information. Learners can learn repeatedly and autonomously, practice in the " electronic classroom", see tri(dimensional models in the " electronic laboratory" . These functions wiil help) the learners to understand, master and expand of their knowledge. After finishing learning, the learners can log in the " examination system " to test the learning effect and then the system wiil guide the learners for their further learning. The platform keeps to the " student-centered" teaching philosophy, follows up the " learn for fun", " learn for knowledge" and " learn for life" training modes. This paper focused on the construction of the engineering drawing platform, and explores the mode for training the high quality military talents. [ABSTRACT FROM AUTHOR]

Lyme disease, caused by Borrelia burgdorferi, is a focally endemic tick-transmitted zoonotic infection. In this study, the major factors underlying synonymous codon-related amino acid usage in the B. burgdorferi genome and bias in synonymous codon usage of the translation initiation region of coding sequences were analyzed. Additionally, adaptation of B. burgdorferi to several of its hosts was analyzed in the context of synonymous codon usage. Principal component analysis (PCA) revealed that nucleotide content at the third synonymous position of a codon influenced the synonymous codon usage pattern, but the strand-specific factor did not influence the synonymous codon usage pattern of B. burgdorferi. In terms of the low GC content of B. burgdorferi coding sequences, the effective number of codons (ENC) showed a significant correlation with GC 3 content (at the synonymous position). For the amino acid usage pattern for B. burgdorferi, PCA showed that the strand-specific factor did not contribute to this pattern, while the properties (aromaticity and hydrophobicity) of the amino acids themselves showed strong correlations with this pattern. Under-represented codons, which were frequently selected in the translation initiation region, possibly play roles in regulating gene expression in B. burgdorferi. In terms of co-evolution and synonymous codon usage patterns, adaptation of B. burgdorferi to different intermediate hosts was apparent to different degrees, and the degree of adaptation of this spirochete to wild animals was stronger than that of humans or mice., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Aim: To investigate the correlation between human epidermal growth factor receptor (HER-2) protein expression and colorectal cancer (CRC) using a case-control study and meta-analysis., Methods: Tumor tissue specimens from 162 CRC patients were selected for the case group. Fifty cases were randomly selected, and normal CRC tissue at least 10 cm away from the tumor margins of these cases was used to generate the control group. The expression of the HER-2 protein in the 162 CRC tissue samples and the 50 adjacent normal mucosa tissue samples was detected via immunohistochemistry. The experimental data were analyzed using SPSS 18.0 software, and R software version 3.1.0 was utilized for further verification., Results: The expression of HER-2 protein in the 162 CRC tissue samples was significantly higher than in the normal tissue specimens. The data showed that the expression of HER-2 in CRC was related to the Dukes' stage, the depth of invasion and lymph node metastasis. The HER-2-positive patients had lower 3- and 5-year OS rates than the HER-2-negative patients, but there was no significant difference. However, there was a statistically significant difference in the 3- and 5-year disease-free survival (DFS) rates of HER-2-positive and HER-2-negative patients. The results of the meta-analysis showed that the expression of HER-2 in CRC patients was statistically significantly increased over that of healthy people. The 3-year DFS rate in HER-2-positive patients was markedly lower than that in HER-2-negative patients., Conclusion: Down-regulation of HER-2 expression might be a dependable strategy for CRC therapy.

Objective: To investigate the chemical constituents of the processed products of Aconitum Vilmorinian Radix., Methods: The constituents were isolated by repeated column chromatography over silica gel, alumina and RP-C18 as well as recrystallization. The structures were elucidated on the basis of spectral analysis and physicochemical properties., Results: Ten compounds were obtained from the methanol extract, and they were identified as yunaconitine (1), 8-deacetyl-yunaconitine (2), geniculatine C (3), vilmorrianine B (4), vilmorrianine C(5), vilmorrianine D (6), talatisamine (7), β-sitosterol (8), β-daucosterol (9) and β-sitosterol acetate (10)., Conclusion: All compounds are obtained from the processed products of Aconitum Vilmoriniani Radix for the first time.

Objective: To study the chemical constituents of chloroform fraction from Aconitum bulleyanum., Methods: The compounds were isolated by various chromatographic techniques and identified by spectroscopic methods., Results: 7 compounds were obtained and identified as yunaconitine (1), crassicaudine (2), foresaconitine (3), chasmaconitine (4), bulleyaconitine A (5), franchetine (6), and beta-sitosterol (7), CONCLUSION: Compounds 2-7 are isolated from this plant for the first time.

Objective: By inhibiting AML1 -ETO fusion gene expression in Kasumi-1 cells with RNAi, to investigate the changes in cell proliferation and cell cycle., Methods: The small interference RNAs (siRNAs) specifically targeting the AML1 -ETO fusion gene were synthesized in vitro and transfected into Kasumi-1 cells by electroporation, the non-specific siRNAs transfected cells were taken as control. EGFP plasmid was transfected into Kasumi-1 cell and the transfection efficiency was detected by FCM. Inhibitory effect of siRNAs were detected by real-time RT-PCR and Western blots. Cell proliferation was measured by CCK-8 assay. DNA content was detected by PI assay., Results: The transfection efficiency was 44.5%. The AML1 -ETO specific siRNAs inhibited AML1 -ETO expression at both mRNA and protein levels. The cell proliferation rate in siRNAs treated group was lower than that in control group 72 h after transfection [(47.90 +/- 0.02)% vs (66.90 +/- 0.08)% , P < 0.05]. The cell cycle was blocked at G1 phase 72 h after siRNAs treatment, the cell proportion in G1 phase being 38.3% and 31.6% in control group, while in G2/M phase being 1.8% and 2.4% respectively., Conclusions: The synthesized siRNAs can inhibit AML1 -ETO fusion gene expression. AML1 -ETO specific siRNA induced the decline of AML1 -ETO fusion protein in Kasumi-1 cell, and then caused the cell cycle blocked in G1 stage and eventually inhibited the cell proliferation.

Objective: To study the reactivation of retinoic acid receptor beta (RARbeta) expression in myeloid leukemia cells by a combination of all-trans retinoic acid (ATRA) with a DNA demethylating agent, decitabine (DAC), and valproic acid (VPA, a histone deacetylase inhibitor),and their effects on cell differentiation and proliferation., Methods: Human myeloid leukemia cells of the line U937 were cultured and treated with all-trans retinoic acid (ATRA), DAC, and VPA. 72 h later cell differentiation test, cloning formation test, and chromatin immunoprecipitation test were performed. Bone marrow specimens were collected from 56 patients with acute myeloblastic leukemia (AML) were cultured and treated with and 10 bone marrow specimens were used as controls. Methylation of RARbeta promoter was detected with methylation specific polymerase chain reaction (MSP) after bisulfite treatment. Relative levels of RARbeta mRNA were assessed with real time quantitative PCR assay. Flow cytometry assay was used to detect the myeloid differentiation marker CD11b in U937 cells. Chromatin immuno-precipitation assay (ChIP) was used to analyze the acetylated histone 3 bound to the retinoic acid response element (RARE) at the promoter region of RARbeta., Results: Methylation of RARbeta was positive in 36 of the 56 (64.3%) AML patients and the U937 myeloid leukemia cells, however, was negative in the marrow mononuclear cells from the 10 healthy donors. The expression of RARbeta in U937 cells was up-regulated after treatment with ATRA (1 micromol/L) plus DAC (1 micromol/L) or VPA (0.5 mmol/L) for 72 hours, especially when the three drugs were used together. ChIP assay showed that the acetylated histone 3 bound to the RARE promoter region was increased after the cells were exposed to ATRA plus DAC/VPA. The data indicated that the reactivated expression of RARbeta might be secondary to the drug-induced histone acetylation as well as DNA demethylation. Treatment of U937 cells with ATRA and DAC/VPA also resulted in increased myeloid differentiation (CD11b expression) and decreased plating efficiency., Conclusion: The repressed expression of RARbeta in myeloid leukemia cells is closely related to both DNA hypermethylation and histone deacetylation, and a combination of ATRA with epigenetic modulators can be beneficial in the treatment of myeloid malignancies.

Objective: To investigate the inhibitory effect of RNA interference on chronic myeloid leukemia (CML) bcr/abl oncogene expression., Methods: The small interference RNAs (siRNAs) were synthesized in vitro. K562 cells stably expressing bcr/abl gene were transfected with the siRNA by electroporation, both the non-transfected cells and non-specific siRNAs transfected cells were taken as controls. The enhanced green fluorescent protein (EGFP) plasmid was used as positive control and the transfection efficiency was detected by flow cytometry. Inhibitory effect of siRNAs was demonstrated by real-time quantitative RT-PCR and Western blots. Cell proliferation was measured by MTT assay and apoptosis by Annexin V-FITC assay., Results: The transfection efficiency was about 70%. The synthesized siRNAs inhibited CML bcr/abl oncogene expression at both mRNA and protein levels. siRNAs could inhibit K562 cell proliferation to 47% and 56% at 24 h and 48 h after transfection, respectively, and induce cell apoptosis from 1.00% in control group to 15.05% and 19.4% at 24 h and 48 h respectively., Conclusion: At the cell level, inhibition of CML bcr/abl oncogene expression by chemically synthesized siRNAs provides the new method for anti-leukemia study.

Objective: To investigate the toxic and DNA damaging effect of acrylamide (AA) on human keratinocytes and its mechanism., Methods: (1) After the keratinocyte cell line HaCaT cells were exposed to AA with different concentrations for 44 hours, cell survival rate was detected by MTT method. (2) The effects of DNA damage of exposed cells were detected by comet assay. (3) After treating the cells with 2.00 mmol/L of AA plus 0.50 mmol/L of 1-aminobenzotriazole (1-ABT), an inhibitor of cytochrome P-450 enzymes (CYP-450), for 4 hours, the relationship between DNA damage and CYP-450 was studied., Results: (1) Cytotoxicity measurement of AA showed that cell survival rate decreased significantly after 44-hour treatment. (2) Cytotoxicity was not detected after 4-hour AA treatment, but significant DNA damage was observed in all treatment groups, and the degree of damage increased with the concentration of AA. Moreover, the tail lengths of comet cells were in dose-effect relationship. As for cells treated by 1-ABT with 2 mmol/L AA, comet rate and tail length were 15.4% and (8.2 +/- 2.0) micro m respectively, which were decreased significantly (P < 0.01) when compared with 2 mmol/L AA treatment group [80.6% and (44.3 +/- 4.0) micro m]., Conclusions: Acrylamide has significant cytotoxicity and genotoxicity on HaCaT cells. AA-induced DNA damage may be related to the oxidative metabolite(s) of AA through CYP-450.