刺果番荔枝中的番荔枝内酯

从刺果番荔枝（Ａｎｎｏｎａ ｍ ｕｒｉｃａｔａ Ｌ．）的种子中分离到３ 个单四氢呋喃型番荔枝内酯类化合物,用波谱方法鉴定为海南哥纳香甲素（ｈｏｗ ｉｉｃｉｎ Ａ, Ｓ１３）、乙素（ｈｏｗ ｉｉｃｉｎ Ｂ, Ｓ５）和新化合物４－去氧海南哥纳香乙素（４－ｄｅｓｏｘｙｈｏｗ ｉｉｃｉｎ Ｂ, Ｓ２）。     

L‐type voltage‐gated calcium channels in stem cells and tissue engineering

L‐type voltage‐gated calcium ion channels (L‐VGCCs) have been demonstrated to be the mediator of several significant intracellular activities in excitable cells, such as neurons, chromaffin cells and myocytes. Recently, an increasing number of studies have investigated the function of L‐VGCCs in non‐excitable cells, particularly stem cells. However, there appear to be no systematic reviews of the relationship between L‐VGCCs and stem cells, and filling this gap is prescient considering the contribution of L‐VGCCs to the proliferation and differentiation of several types of stem cells. This review will discuss the possible involvement of L‐VGCCs in stem cells, mainly focusing on osteogenesis mediated by mesenchymal stem cells (MSCs) from different tissues and neurogenesis mediated by neural stem/progenitor cells (NSCs). Additionally, advanced applications that use these channels as the target for tissue engineering, which may offer the hope of tissue regeneration in the future, will also be explored.     

BatAlign: an incremental method for accurate alignment of sequencing reads

Structural variations (SVs) play a crucial role in genetic diversity. However, the alignments of reads near/across SVs are made inaccurate by the presence of polymorphisms. BatAlign is an algorithm that integrated two strategies called ‘Reverse-Alignment’ and ‘Deep-Scan’ to improve the accuracy of read-alignment. In our experiments, BatAlign was able to obtain the highest F-measures in read-alignments on mismatch-aberrant, indel-aberrant, concordantly/discordantly paired and SV-spanning data sets. On real data, the alignments of BatAlign were able to recover 4.3% more PCR-validated SVs with 73.3% less callings. These suggest BatAlign to be effective in detecting SVs and other polymorphic-variants accurately using high-throughput data. BatAlign is publicly available at https://goo.gl/a6phxB.     

云南药山自然保护区蕨类区系研究

基于馆藏标本,对云南药山自然保护区蕨类进行区系分析.结果表明:该保护区共有蕨类30科、67属、177种及10变种;属的区系地理成分可划分为10个类型11个亚型;种的区系地理成分可划分为9个类型、20个亚型及7个变型;该保护区温带区系成分占优势;与相邻地区区系成分比较发现,蕨类区系与云南药山联系的紧密程度为:轿子雪山>梅里雪山及附近地区>玉龙雪山>黄山.     

High Resolution Size Analysis of Fetal DNA in the Urine of Pregnant Women by Paired-End Massively Parallel Sequencing

Background

Fetal DNA in maternal urine, if present, would be a valuable source of fetal genetic material for noninvasive prenatal diagnosis. However, the existence of fetal DNA in maternal urine has remained controversial. The issue is due to the lack of appropriate technology to robustly detect the potentially highly degraded fetal DNA in maternal urine.

Methodology

We have used massively parallel paired-end sequencing to investigate cell-free DNA molecules in maternal urine. Catheterized urine samples were collected from seven pregnant women during the third trimester of pregnancies. We detected fetal DNA by identifying sequenced reads that contained fetal-specific alleles of the single nucleotide polymorphisms. The sizes of individual urinary DNA fragments were deduced from the alignment positions of the paired reads. We measured the fractional fetal DNA concentration as well as the size distributions of fetal and maternal DNA in maternal urine.

Principal Findings

Cell-free fetal DNA was detected in five of the seven maternal urine samples, with the fractional fetal DNA concentrations ranged from 1.92% to 4.73%. Fetal DNA became undetectable in maternal urine after delivery. The total urinary cell-free DNA molecules were less intact when compared with plasma DNA. Urinary fetal DNA fragments were very short, and the most dominant fetal sequences were between 29 bp and 45 bp in length.

Conclusions

With the use of massively parallel sequencing, we have confirmed the existence of transrenal fetal DNA in maternal urine, and have shown that urinary fetal DNA was heavily degraded.     

植物焦磷酸酶(PPase)的研究进展

植物焦磷酸酶(PPase)可分为存在于细胞质中可溶性的无机焦磷酸酶和与膜结合的不可溶性焦磷酸酶.后者不仅能水解焦磷酸,同时还具有质子泵的功能.橡胶树乳管中与黄色体膜结合的不可溶性焦磷酸酶,是调控橡胶生物合成的一个必不可少的酶.对植物焦磷酸酶的结构及其功能和分子生物学研究的进展进行了综合论述,并着重阐述了焦磷酸酶在橡胶树橡胶生物合成中的作用.     

肺动脉内皮细胞与肺动脉平滑肌细胞增殖的相互调节

血管内皮细胞和血管平滑肌细胞在结构和功能上关系密切,二者的相互关系在血管舒缩和血管壁结构的调节中起重要作用。本文观察了培养的小牛肺动脉内皮细胞（ＰＡＥＣ）和肺动脉平滑肌细胞（ＰＡＳＭ）在细胞增殖方面的相互调节作用。混合培养的ＰＡＥＣ和ＰＡＳＭ细胞的３Ｈ－ＴｄＲ参入明显降低（Ｐ＜０．００１,与对照组相比）。无论向培养的ＰＡＥＣ和ＰＡＳＭ中分别加入ＰＡＳＭ和ＰＡＥＣ的条件培养基还是二者共培养时,均发现ＰＡＥＣ的３Ｈ－ＴｄＲ参入明显降低,而ＰＡＳＭ的３Ｈ－ＴｄＲ明显升高（Ｐ＜０．０５,与对照组相比）。流式细胞测定也发现共培养时ＰＡＥＣ的Ｇ１期细胞增多,Ｇ２／Ｍ期细胞减少;而ＰＡＳＭ的Ｇ１期细胞减少,Ｇ２／Ｍ期细胞增多。共培养的ＰＡＳＭ细胞内ｃＡＭＰ增加,ｃＧＭＰ含量降低;而ＰＡＥＣ细胞的ｃＡＭＰ和ｃＧＭＰ含量均降低（Ｐ＜０．０１,与对照组相比）。上述结果提示,ＰＡＥＣ和ＰＡＳＭ相互作用可能通过第二信使而调节它们本身的增殖     

Flavonoids of <Emphasis Type="Italic">Rosa roxburghii</Emphasis> Tratt exhibit radioprotection and anti-apoptosis properties via the Bcl-2(Ca<Superscript>2+</Superscript>)/Caspase-3/PARP-1 pathway

The objective of our study was to assess the radioprotective effect of flavonoids extracted from Rosa roxburghii Tratt (FRT) and investigate the role of Bcl-2(Ca²⁺)/Caspase-3/PARP-1 pathway in radiation-induced apoptosis. Cells and mice were exposed to ⁶⁰Co γ-rays at a dose of 6 Gy. The radiation treatment induced significant effects on tissue pathological changes, apoptosis, Ca²⁺, ROS, DNA damage, and expression levels of Bcl-2, Caspase-3 (C-Caspase-3), and PARP-1. The results showed that FRT acted as an antioxidant, reduced DNA damage, corrected the pathological changes of the tissue induced by radiation, promoted the formation of spleen nodules, resisted sperm aberration, and protected the thymus. FRT significantly reduced cell apoptosis compared with the irradiation group. The expression of Ca²⁺ and C-Caspase-3 was decreased after FRT treatment compared with the radiation-treated group. At the same time, expression of prototype PARP-1 and Bcl-2 increased, leading to a decrease in the percentage of apoptosis cells in FRT treatment groups. We conclude that FRT acts as a radioprotector. Apoptosis signals were activated via the Bcl-2(Ca²⁺)/Caspase-3/PARP-1 pathway in irradiated cells and FRT inhibited this pathway of apoptosis by down-regulation of C-Caspase-3 and Ca²⁺ and up-regulation of prototype PARP-1 and Bcl-2.