New Immunomodulating Polyhydroxypregnane Glycosides from the Roots of Cynanchum otophyllum C.K.Schneid.

Seven new polyhydroxypregnane glycosides, named cynotophyllosides P–V, together with three known analogs were isolated from the roots of Cynanchum otophyllum C.K.Schneid . Their structures were elucidated by a variety of spectroscopic techniques, as well as acid‐catalyzed hydrolysis. All isolates were tested for their immunological activities in vitro against Con A‐ and LPS‐induced proliferation of mice splenocytes. Immunoenhancing (for 1 , 9 ) and immunosuppressive (for 2 ) activities were observed. Furthermore, cynotophylloside R ( 3 ) showed immunomodulatory as it enhanced the proliferation of splenocytes in low concentration and suppressed immune cells in concentration more than 1.0 μg/ml.     

Cytotoxic Spliceostatin Analogs from Pseudomonas sp.

Two new spliceostatin analogs, designed as spliceostatins J and K ( 1 and 2 ), were isolated and identified from the culture of Pseudomonas sp., along with two known ones, FR901464 ( 3 ) and spliceostatin E ( 4 ). Their structures were elucidated by detailed interpretation of their spectroscopic data, especially 2D‐NMR and HR‐ESI‐MS. Spliceostatin J ( 1 ) represented the first example of spliceostatins bearing an unusual hexahydrofuro[3,4‐b]furan moiety. Biological assay showed all the isolated compounds except 1 displayed potent cytotoxic activities against two cancer cell lines (MDA‐MB‐231 and A‐549). Structure‐activity‐relationship studies revealed that the tetrahydropyran ring in spliceostatin analogs was necessary for their bioactive retention.     

Circular RNA circ_0001017 Sensitizes Cisplatin-Resistant Gastric Cancer Cells to Chemotherapy by the miR-543/PHLPP2 Axis

Biochemical Genetics - Resistance to cisplatin (CDDP) remains a major challenge for the treatment of gastric cancer (GC). Circular RNAs (circRNAs) have been implicated in the development of CDDP...     

A Putative Adhesin-encoding Gene AOL_s00007g5 is involved in the Mycelial Growth and Development of Nematode-trapping Fungus Arthrobotrys oligospora

Applied Biochemistry and Microbiology - Arthrobotrys oligospora is one of the most commonly studied fungi that can form abundant traps to capture and consume nematodes at the parasitic stage....     

神经嵴细胞和神经嵴病及其致病机制的研究进展

神经嵴细胞(neural crest cells,NCCs)是一类脊椎动物特有的可迁移的多能干细胞,其可分化为软骨细胞、神经元和黑色素细胞等多种类型细胞。NCCs的形成、迁移和分化受到严格调控,任何扰乱NCCs发育的因素都可导致胚胎发育畸形。由神经嵴细胞发育异常所导致的一系列疾病统称为神经嵴病(neurocristopathies,NCPs)。NCPs种类繁多且表型复杂,可累及人体多个部位(颅面部、心脏、肠胃和皮肤等),严重危害患者的身体机能和心理健康。NCPs占所有出生缺陷患儿的1/3,遗传因素是导致NCPs的主要风险因素,但环境风险因子以及基因–环境交互作用异常也可导致NCPs。本文对神经嵴细胞和神经嵴病及其致病机制进行综述,为系统认知神经嵴细胞发育以及神经嵴病提供参考,为了解神经嵴病的病因以及开展有效防控提供科学支撑。     

Molecular Mechanism of Selenium Affecting the Synthesis of Flavonoids in G. biloba Leaves

Plant Molecular Biology Reporter - Flavonoids from Ginkgo biloba have antioxidant and free radical scavenging activity. In the present study, we used different concentrations of OS (organic...     

一株虾池来源的螺旋拟柱孢藻藻株的分离鉴定及重金属离子Cu~(2+)、Cd~(2+)和Pb~(2+)对其生长的影响

【目的】探讨凡纳滨对虾养殖水体中入侵蓝藻拟柱孢藻的生长生理特性。【方法】从汕头澄海人工对虾养殖池分离纯化藻株,通过形态及其16SrRNA基因鉴定,之后在CT与BG11两种蓝藻通用培养基的基础上优化最佳培养条件,最后分析了不同浓度的3种重金属离子即Cu~(2+)(0–0.8 mg/L)、Cd~(2+)(0–4 mg/L)和Pb~(2+)(0–80 mg/L)对藻株生长的影响。【结果】澄海虾池来源的分离纯化藻株形态呈卷曲螺旋型,16S rRNA基因序列与多株其他来源的拟柱孢藻相似度均达98%以上。实验室培养,藻株最佳生长状态的培养条件是在BG11培养基的基础上调整氮浓度及氮磷比分别为N 62 mg/L,N︰P=9︰1,在此条件下,藻丝生物量可达(0.632±0.170)×107/L,藻丝比平均生长速率最高为(0.063±0.001)/d。本分离藻株活体对重金属Cu~(2+)、Cd~(2+)和Pb~(2+)具有一定的耐受性,其耐受浓度范围分别为0–0.2、0–0.5和1–40 mg/L,其中,Cu~(2+)和Cd~(2+)对藻的生长具有抑制作用,而且此抑制作用随着金属离子剂量的增加及作用时间的延长更加显著,Cu~(2+)和Cd~(2+)对藻体的半数抑制浓度(96 h EC50)分别为0.125和0.551 mg/L;而浓度范围为0–80 mg/L的Pb~(2+)对藻体的生长则表现为低剂量(≤40 mg/L)呈促进,高剂量(≥80 mg/L)则抑制。【结论】从凡纳滨对虾养殖池中分离鉴定出一株形态呈螺旋型的拟柱孢藻,命名为螺旋拟柱孢藻(Cylindrospermopsis raciborskii helix),本藻株活体能够在一定浓度的Cu~(2+)、Cd~(2+)和Pb~(2+)中生长,为螺旋拟柱孢藻活藻生物吸附重金属离子而改善虾池水体环境提供了可能性。     

Lupane‐ and Friedelane‐Type Triterpenoids from Celastrus stylosus

Two new triterpenoids, 30‐hydroxylup‐20(29)‐ene 3β‐caffeate ( 1 ) and 24‐nor‐friedelan‐6α,10‐dihydroxy‐1,2‐dioxo‐4,7‐dien‐29‐oic acid ( 2 ), together with eight known compounds 3 – 10 , were isolated from the roots of Celastrus stylosus. The structures of these compounds were elucidated on the basis of spectroscopic analyses. To the best of our knowledge, this represents the first study on the chemical constituents of C. stylosus. The antiproliferative activities of the triterpenoids against six human cancer cell lines (PANC‐1, A549, PC‐3, HepG2, SGC‐7901, and HCCLM3) were evaluated. Compounds 3, 4 , and 10 exhibited comparable activities against PC‐3 and HCCLM3 cell lines as the positive control taxol.     

Nonrigid Registration Regularized by Shape Information: Application to Atlas Construction of Cardiac CT Images

Cardiac atlases play an important role in the computer-aided diagnosis of cardiovascular diseases, in particular they need to deal with large and highly variable image datasets. In this paper, we propose a new nonrigid registration algorithm incorporating shape information, to produce comprehensive atlases. For one thing, the multiscale gradient orientation features of images are combined to form the construction of multifeature mutual information. Additionally, the shape information of multiple-objects in images is incorporated into the cost function for registration. We demonstrate the merits of the new registration algorithm on the 3D data sets of 15 patients. The experimental results show that the new registration algorithm can outperform the conventional intensity-based registration method. The obtained atlas can represent the cardiac structures more accurately.