豚鼠脑基底动脉平滑肌细胞的原代培养及鉴定

目的本研究联合使用直接贴壁法和酶消化法培养细胞,从豚鼠脑基底动脉中提取平滑肌细胞,为相关实验研究提供材料。方法从豚鼠颅内分离出脑基底动脉,用0.125%胰蛋白酶进行消化并将组织块贴壁,细胞用含20%胎牛血清的DMEM/F-12培养基进行培养。采用自然纯化法,并根据不同细胞贴壁能力的差异性对细胞进行纯化。通过形态学观察、免疫荧光、免疫组织化学法及Western blot检测对细胞进行鉴定。结果 85%组织块存活,第4代平滑肌细胞纯度达95%。镜下可见细胞呈典型的"峰-谷"样生长,免疫荧光、免疫组织化学法及Western blot检测显示,平滑肌细胞特异性的肌动蛋白呈阳性表达。结论通过本实验可以得到大量高纯度的豚鼠脑基底动脉平滑肌细胞,有望为颅内动脉粥样硬化等病理生理变化的体外研究及脑血管平滑肌药物评价提供一个理想的实验材料。

Antifungalmycin,an antifungal macrolide from Streptomyces padanus 702

Two polyene macrolide antibiotics:antifungalmycin(1)and fungichromin(2)were isolated from the culture mycelia of Streptomyces padanus 702 via bioactivity-guided fractionation using various chromatographic procedures.Their structures were elucidated on the basis of spectral analysis,and 1 is a new polyene macrolide.Compounds 1 and 2 showed significant inhibition against Gibberella zeae with EC_(50)values of 26.71 and 2.21μg/mL,Fusicoccum sp.(plantain head blight)with EC_(50)values of 23.4 and 3.17μg/mL,Mucor ssp.8894 with EC_(50)values of 28.80 and 2.11μg/mL,Ustilaginoidea virens with EC_(50)values of 26.72 and 0.21μg/mL,respectively.This shows that the microbial secondary metabolites 1 and 2 have the potential to be developed as agricultural fungicides for use against G.zeae,Fusicoccum sp.,Mucor ssp.8894,and U.virens.

SCR-22 of pollen-dominant S haplotype class is recessive to SCR-44 of pollenrecessive S haplotype class in Brassica rapa

SCR/SP11 encodes the male determinant of recognition specificity of self-incompatibility(SI)in Brassica species and is sporophytically expressed in the anther tapetum.Based on dominance relationships in pollen and nucleotide sequence similarity,the S haplotypes in Brassica have been classified as class I or class II,with class-I S haplotypes being dominant over class-II S haplotypes.Here,we revealed that S-22 in B.rapa belonging to class I is recessive to class-II S-44 and class-I S-36 in pollen,whereas it is dominant over S-60,S-40,and S-29 based on pollination tests.SCR/SP11 of S-22(SCR-22)was sequenced,revealing that the deduced amino-acid sequence of SCR-22 has the longest C-terminal domain among the SCR/SP11 sequences.The expression of SCR-22 was found to be suppressed in S-22/S-44 and S-22/S-36 heterozygotes.Normal transcription of SCR-44 was considered to be due to the transcription suppression of Smi sRNA of the S-22 haplotype and a very low methylation state of the SCR-44 promoter region in the tapetum of S-22/S-44 heterozygotes.In SCR-22,only the cytosine residue located at the–37 bp position of the promoter region was hypermethylated in the tapetum of S-22/S-44 heterozygotes,and few methylated cytosines were detected in the promoter and coding regions of SCR-22 in S-22/S-36 heterozygotes.SCR-22 was also expressed in microspores in S-22 homozygotes but not in S-22/S-44 and S-22/S-36 heterozygotes.These results suggest that a mechanism different from class-II SCR/SP11 suppression may operate for the suppression of recessive class-I SCR-22 in S heterozygotes.

Strategies for Precise Engineering and Conjugation of Antibody Targeted-nanoparticles for Cancer Therapy

Improvements in the diagnosis and treatment of cancer are urgently needed for use in nanotechnology.Nanoparticles(NPs)can reduce the side effects of traditional chemotherapy by sustained release of loaded drugs and increase therapeutic efficiency.NPs can also enhance endothelial permeation retention by size effect and its accumulation in tumor cells through passive targeting.Furthermore,it is critical to treat cancer with a controlled targeted drug which can be specifically delivered into tumor cells and released there,resulting in a targeted therapy to eradicate tumor cells while sparing normal cells.To this end,antibody-mediated targeting therapy has been developed,but imperfections in antibodies(Abs)limit this therapy.Therefore,the combination of NPs and Abs has been highly valued in recent years,because conjugating special Abs on the surface of NPs can increase targeting efficiency,enabling selective delivery of anti-cancer drugs to tumor cells.In this mini-review,we would like to enumerate the strategies for the conjugation of Abs to the surface of the NPs as well as the precise engineering of targeted NPs.The application of targeting antibody fragments in this drug delivery system will also be discussed.

Risk factors and prediction of macrosomia in a cohort study

Objective: To investigate the risk factors of macrosomia and to predict the risk of macrosomia so as to reduce the incidence of macrosomia. Methods: A total of 2063 pregnant women who met the inclusion criteria were selected as the subjects from February 2016 to April 2017 in Jiading District Maternal and Child Health Hospital of Shanghai and Pudong New Area Maternal and Child Health Hospital. According to the birth weight of the neonates, the neonates were divided into the macrosomia group (neonatal weight > 4000 g, n=125) and the normal infant group (2500 g < neonatal weight < 4000 g, n=1938).The general data of age, number of pregnant women, BMI before pregnancy, gestational diabetes mellitus, glucose tolerance, weight gain during pregnancy, birth weight and gestational week were compared between the two groups. Multivariate logistic regression was used to analyze the risk factors of macrosomia. Results: ①There were significant differences in BMI, glucose tolerance, fasting blood sugar, weight gain in the second trimester, weight gain in the third trimester, birth weight and gestational week between the two groups (P<0.05). ②Single factor analysis showed that pre-pregnancy BMI, gestational week at first diagnosis, fasting blood glucose tolerance, weight gain in the second trimester, weight gain in the third trimester, gestational week and birth weight were the influencing factors of macrosomia (P<0.05). ③Multi-factor analysis showed that gestational weeks, gestational diabetes, fasting glucose tolerance and weight growth in the second trimester were the main factors affecting the production of macrosomia, among which gestational diabetes was the protective factor, while gestational weeks, fasting glucose tolerance and weight growth in the second trimester were the risk factors. Conclusion: The high risk factors for macrosomia are gestational weeks, glucose tolerance, fasting blood sugar and weight gain in the second trimester of pregnancy.We should strengthen regular obstetric examination, health care during pregnancy, reasonable diet and proper exercise, and strictly control the weight gain during the second trimester of pregnancy. At the same time, we should monitor blood sugar in time so as to reduce the incidence of macrosomia.

Arabidopsis AT-hook Protein TEK Positively Regulates the Expression of Arabinogalactan Proteins for Nexine Formation

Nexine is a conserved layer of the pollen wall. We previously reported that the nexine layer is absent in the knockout mutant of Arabidopsis TRANSPOSABLE ELEMENT SILENCING VIA AT-HOOK （TEK） gene. In this study, we investigated the molecular regulatory functions of TEK in pollen development and identified the genes encoding Arabinogalactan proteins （AGPs） as direct targets of TEK, which are essential for nexine formation. Phenotypic similarity between tek and the TEK-SRDX transgenic lines suggest that TEK plays a role in transcriptional activation in anther development. Microarray analysis identified a total of 661 genes downregulated in tek, including four genes encoding AGPs, AGP6, AGP11, AGP23, and AGP40. Electrophoretic mobility shift assays showed that TEK could directly bind the nuclear matrix attachment region （MAR） and the promoter of AGP6. Chromatin immunoprecipitation followed by PCR analysis demonstrated that TEK is enriched in the promoters of the four AGP genes. Expression of AGP6 driven by the TEK promoter in tek partially rescued both nexine formation and plant fertility. These results indicate that TEK directly reg- ulates AGP expression in the anther to control nexine layer formation. We also proposed that glycoproteins might be essential components of the nexine laver in the oollen wall.

A New Periodic Solution to Jacobi Elliptic Functions of MKdV Equation and BBM Equation

Based on the homogeneous balance method, the Jacobi elliptic expansion method and the auxiliary equation method, the first elliptic function equation is used to get a new kind of solutions of nonlinear evolution equations. New exact solutions to the Jacobi elliptic function of MKdV equations and Benjamin-Bona-Mahoney （BBM） equations are obtained with the aid of computer algebraic system Maple. The method is also valid for other （l＋l）-dimensional and higher dimensional systems.

Expression of centromere protein-C(CENP-C) in villus tissue of the first-trimester spontaneous abortion and its correlation with chromosome segregation

Objective To investigate the expression of centromere protein-C （CENP-C） in villus tissue of the first-trimester spontaneous abortion （SA） and the correlation study of CENP-C expression with chromosome segregation. Methods Fluorescence in situ hybridization （FISH） and G-banded karyotype analysis were used to detect the numerical chromosome abnormality in 94 villus tissues of women with SA. The participants were separated into case group （n=30） and control group （n--30） according to the results with FISH. The qRT-PCR and Western blotting analysis were used to assess the expression level of CENP-C. Results Forty-eight （51.06%） cases had observed the numerical chromosome abnormality, including 30positive cases and the positive rate was 31.91%. The main types of variation included trisomy 16, 21, 22, X monosomy and triploid. The expression levels of CENP-C mRNA and protein in case group were statistically higher than that in control group （P〈0.05）. Conclusion Expression of CENP-C in the villus tissues of women might be related to SA induced by chromosomal aneuploid.

Reaction inside a viral protein nanocage： Mineralization on a nanoparticle seed after encapsulation via self-assembly

Protein nanocages are ideal templates for the bio-inspired fabrication of nanomaterials due to several advantageous properties. During the mineralization of nanoparticles （NPs） inside protein nanocages, most studies have employed a common strategy： seed formation inside protein nanocages followed by seeded NP growth. However, the seed formation step is restricted to gentle reaction conditions to avoid damage to the protein nanocages, which may greatly limit the spectrum of seed materials used for NP growth. We put forward a simple route to circumvent such a limitation： encapsulation of a preformed NP as the seed via self-assembly, followed by the growth of an outer metal layer. Using such a method, we succeeded in mineralizing size-tunable Au NPs and Au@Ag core-shell NPs （〈10 nm in diameter） with narrow size distributions inside the virus-based NPs of simian virus 40. The present route enables the utilization of NPs synthesized under any conditions as the starting seeds for nanomaterial growth inside protein nanocages. Therefore, it potentially leads to novel bioinorganic chimeric nanomaterials with tailorable components and structures.

Extracorporeal Membrane Oxygenation Support for Incessant Tachyarrhythmia-lnduced Severe Cardiogenic Shock

To the Editor： Junctional ectopic tachycardia is uncommon; however, it is one of the most serious incessant supraventricular tachycardia. This tachyarrhythmia has a high association with tachycardia-induced cardiomyopathy or myocardial depressant.