Expression of apoptosis-related genes in the endometrium of polycystic ovary syndrome patients during the window of implantation

The present study investigated the expression of the apoptosis-related genes fas-associated via death domain (FADD) and Bcl-2 in the endometrium during the window of implantation in polycystic ovary syndrome (PCOS) patients. The aim was to explore the role of cell apoptosis in endometrial receptivity during this period. The subjects were divided into experimental and control group. The experimental group comprised 12 infertile women with PCOS, and the control group comprised 12 women who were infertile because of tubal pathological factors but had normal menstrual cycles. Endometria were collected by biopsy 7d after ovulation. Six samples from each group were randomly selected and subjected to gene chip analyses. The expression of endometrial FADD and Bcl-2 was determined by immunohistochemistry, and cell apoptosis was detected by the TUNEL method. Compared with the control group, 194 differentially expressed genes were found in the PCOS group, 102 of which were upregulated and 92 were downregulated. The differentially expressed genes were divided into 15 types according to function. Among the nine genes related to cell apoptosis, five (including Bcl-2) were upregulated and four were downregulated (including FADD). Bcl-2 expression during the window of implantation in the PCOS group increased compared with the control group, showing a significant difference (P<0.05). FADD expression in the PCOS group notably decreased compared with that in the control group, which also showed a significant difference (P<0.05). Cell apoptosis analysis showed a significant difference between the average apoptotic indices in the PCOS and control groups (P<0.05). Significant differences were observed between the endometrial gene expression in the PCOS and control groups. The decrease in cell apoptosis during the window of implantation in PCOS patients may be one of the causes of the reduced endometrial receptivity.     

Predation of the oriental fruit fly,Bactrocera dorsalis puparia by the red imported fire ant,Solenopsis invicta: role of host olfactory cues and soil depth

Predation by red imported fire ants, Solenopsis invicta on oriental fruit fly, Bactrocera dorsalis puparia was evaluated. No significant olfactory response of the workers was observed at 0, 2 and 4 days after fly pupation, whereas the workers were significantly attracted by the 6th day old puparia. We found S. invicta that predated on puparia of B. dorsalis in the field. The predation rate was negatively correlated with the depth of puparia in the soil. The predation rate was 70% at 4 cm depth; whereas, zero predation rate was observed at 6 cm depth. The predation rate was also significantly affected by soil moisture. The predation rate was 66.5% and 72.1% at soil moisture values of 40% and 80%, respectively, and no predation occurred at soil moisture value of 0%.     

Regulation of cAMP on the first mitotic cell cycle of mouse embryos

Mitosis promoting factor (MPF) plays a central role during the first mitosis of mouse embryo. We demonstrated that MPF activity increased when one-cell stage mouse embryo initiated G2/M transition following the decrease of cyclic adenosine 3', 5'-monophosphate (cAMP) and cAMP-dependent protein kinase (PKA) activity. When cAMP and PKA activity increases again, MPF activity decreases and mouse embryo starts metaphase-anaphase transition. In the downstream of cAMP/PKA, there are some effectors such as polo-like kinase 1 (Plk1), Cdc25, Mos (mitogen-activated protein kinase kinase kinase), MEK (mitogen-activated protein kinase kinase), mitogen-activated protein kinase (MAPK), Wee1, anaphase-promoting complex (APC), and phosphoprotein phosphatase that are involved in the regulation of MPF activity. Here, we demonstrated that following activation of MPF, MAPK activity was steady, whereas Plk1 activity fluctuated during the first cell cycle. Plk1 activity was the highest at metaphase and decreased at metaphase-anaphase transition. Further, we established a mathematical model using Gepasi algorithm and the simulation was in agreement with the experimental data. Above all the evidences, we suggested that cAMP and PKA might be the upstream factors which were included in the regulation of the first cell cycle development of mouse embryo.     

Structure-activity relationship study of a series of caspase inhibitors containing γ-amino acid moiety for treatment of cholestatic liver disease

A series of caspase inhibitors containing γ-amino acid moiety have been synthesized. A systemic study on their structure-activity relationship of anti-apoptotic cellular activity is presented. These efforts led to the discovery of compound 20o as a potent caspase inhibitor, which demonstrated preclinical ameliorating total bilirubin efficacy with a significantly improved pharmacokinetic profile.     

High-throughput screening-based identification of paramyxovirus inhibitors

Several members of the paramyxovirus family constitute major human pathogens that, collectively, are responsible for major morbidity and mortality worldwide. In an effort to develop novel therapeutics against measles virus (MV), a prominent member of the paramyxovirus family, the authors report a high-throughput screening protocol that uses a nonrecombinant primary MV strain as targets. Implementation of the assay has yielded 60 hit candidates from a 137,500-entry library. Counterscreening and generation of dose-response curves narrows this pool to 35 compounds with active concentrations 500. Library mining for structural analogs of several confirmed hits combined with retesting of identified candidates reveals a high accuracy of primary hit identification. Eleven of the confirmed hits interfere with viral entry, whereas the remaining 24 compounds target postentry steps of the viral life cycle. Activity testing against selected members of the paramyxovirus family reveals 3 patterns of activity: 1) exclusively MV-specific blockers, 2) inhibitors of MV and related viruses of the same genus, and 3) broader range inhibitors with activity against a different Paramyxovirinae genus. Representatives of the last class may open avenues for the development of broad-range paramyxovirus inhibitors through hit-to-lead chemistry. ( Journal of Biomolecular Screening 2008:591-608).     

Optimization of CCR4 antagonists: side-chain exploration

The design, synthesis, and activity of novel and selective small molecule antagonists of the CC chemokine receptor-4 (CCR4) are presented. Compound 8c was efficacious in a murine allergic inflammation model (ED(50) 30 mg/kg).     

Insights into xanthine riboswitch structure and metal ion-mediated ligand recognition

Riboswitches are conserved functional domains in mRNA that mostly exist in bacteria. They regulate gene expression in response to varying concentrations of metabolites or metal ions. Recently, the NMT1 RNA motif has been identified to selectively bind xanthine and uric acid, respectively, both are involved in the metabolic pathway of purine degradation. Here, we report a crystal structure of this RNA bound to xanthine. Overall, the riboswitch exhibits a rod-like, continuously stacked fold composed of three stems and two internal junctions. The binding-pocket is determined by the highly conserved junctional sequence J1 between stem P1 and P2a, and engages a long-distance Watson–Crick base pair to junction J2. Xanthine inserts between a G–U pair from the major groove side and is sandwiched between base triples. Strikingly, a Mg²⁺ ion is inner-sphere coordinated to O6 of xanthine and a non-bridging oxygen of a backbone phosphate. Two further hydrated Mg²⁺ ions participate in extensive interactions between xanthine and the pocket. Our structure model is verified by ligand binding analysis to selected riboswitch mutants using isothermal titration calorimetry, and by fluorescence spectroscopic analysis of RNA folding using 2-aminopurine-modified variants. Together, our study highlights the principles of metal ion-mediated ligand recognition by the xanthine riboswitch.     

The Rho kinase inhibitor Y-27632 facilitates the differentiation of bone marrow mesenchymal stem cells

The selective in vitro expansion and differentiation of multipotent stem cells are critical steps in cell-based regenerative therapies, but technical challenges have limited cell yield and thus the success of these potential treatments. The Rho GTPases and downstream Rho kinases (Rho coiled-coil kinases or ROCKs) are central regulators of cytoskeletal dynamics during the cell cycle and thus help determine the balance between stem cells self-renewal, lineage commitment, and apoptosis. Here, we examined if suppression of ROCK signaling enhances the efficacy of bone marrow-derived mesenchymal stem cells (BMSCs) differentiation into neurons and neuroglial cells. BMSCs were cultured in epidermal growth factor (EGF, 10 µg/l) and basic fibroblastic growth factor (bFGF, 10 µg/l) in the presence or absence of the Rho kinase inhibitor Y-27632 (10 µM). The expression levels of neuron-specific enolase (NSE) and glial fibrillary acidic protein (GFAP) were detected by immunofluorescence and Western blotting. The average number of NSE-positive cells increased from 83.20 ± 8.677 (positive ratio 0.2140 ± 0.0119) to 109.20 ± 8.430 (positive ratio 0.3193 ± 0.0161) per visual field in the presence of Y-27632, while GFAP-positive cell number increased from 96.30 ± 8.486 (positive ratio 0.18 ± 0.0152) to 107.50 ± 8.683 (positive ratio 0.27 ± 0.0115) (P < 0.05 for both). Both NSE and GFAP protein expression levels were enhanced significantly by Y-27632 treatment (NSE: 0.74 ± 0.05 vs. 1.03 ± 0.06; GFAP: 0.64 ± 0.08 vs. 0.97 ± 0.05, both P < 0.01) as indicated by Western blots. The Rho kinase inhibitor Y-27632 concomitant with EGF and bFGF stimulation promotes BMSC differentiation into neural cells. Control of Rho kinase activity may enhance the efficiency of stem cell-based treatments for neurodegenerative diseases.     

白及小分子热激蛋白BsHsp17.3基因的克隆与表达分析

为了探索人工栽培白及的适宜条件,该研究以湖北省十堰市野生白及为对象,采用同源克隆和3'RACE技术,从白及(Bletilla striata)中获得与热激蛋白合成有关的BsHsp17.3基因,并分析BsHsp17.3基因对不同胁迫的响应。结果表明:BsHsp17.3基因开放阅读框长度为453 bp,编码150个氨基酸;蛋白的分子量为17.42 kD,等电点为6.33。进化树分析表明BsHSP17.3蛋白与同为兰科的铁皮石斛进化关系较近,同在一分支上。半定量RT-PCR分析显示BsHsp17.3基因在白及根、叶、鳞茎及花组织中的表达具有特异性,且BsHsp17.3基因在叶中的表达量较高,在鳞茎及花中不表达。实时荧光定量PCR检测显示BsHsp17.3对非生物胁迫高温、低温具有明显应答反应,20%PEG模拟干旱胁迫不诱导该基因表达,推测该基因在白及防止倒苗过程中可能发挥一定作用。