The actual effects of ethylene oxide (EO) exposure on diabetes population are unknown. This prospective study aimed to examine the association of EO with all-cause mortality risk among adults with different stages of diabetes progression. Study participants were selected from NHANES 2013-2018. The mortality was ascertained through linkage to National Death Index files. Data were analyzed using weighted Cox proportional regressions to examine the associations of hemoglobin adducts of EO (HbEO) with all-cause mortality risk. Restricted cubic spline was applied to flexibly model the non-linear association. Results showed the median of follow-up period was 48.0 months. The participants with diabetes had the highest mortality (p = 0.001). The association of all-cause mortality risk with HbEO was overall positive among diabetes (weighted covariates-adjusted HR: 1.089, 95% CI: 1.028-1.155) but not non-diabetes participants. Among diabetes participants, the association was non-linear (p for non-linearity test: 0.023) and was non-significant when the HbEO level was higher than 310.24 pmol/g Hb. In conclusion, EO may increase the mortality risk among diabetes population through aggravating the diabetes-mediated metabolic disorders. The non-linear association found for the first time may reflect the complex physiological effects of the enzymes that contribute to EO endogenous formation or metabolism.

胰岛素/Akt信号通路受阻所致的骨骼肌细胞蛋白异常分解,可能是骨骼肌萎缩发生的重要原因.不同n-3多不饱和脂肪酸在骨骼肌细胞内、外作用于胰岛素/Akt信号通路上的多个位点,均有助于维持通路的正常运作.其中,植物来源n-3多不饱和脂肪酸ALA能通过活化胰岛β细胞胞膜的GPR40直接促进胰岛素分泌;海鱼来源n-3多不饱和脂肪酸EPA与DHA能有效维持骨骼肌细胞内Akt活性并增加胰岛素敏感性.本文通过对相关文献的归纳总结,阐释n-3多不饱和脂肪酸基于胰岛素/Akt信号通路抑制骨骼肌细胞蛋白异常分解的机制,为通过膳食手段干预骨骼肌萎缩提供新的思路.

The aim of this study is to research whether stearidonic acid (SDA) has insulinotropic effect and the mechanisms. MIN6 pancreatic β-cells were treated with SDA and effects were analyzed. Protein and mRNA expressions of G protein-coupled receptor 40 (GPR40) increased after 24-h SDA treatment, whereas there was no statistical difference of cellular SDA composition between SDA and control groups. The cytosolic Ca2+ increased in 15 s after treatment, but increment was inhibited when MIN6 cells were preincubated with U-73122 (phospholipase C inhibitor) or BAPTA-AM (Ca2+ chelator). The glucose-stimulated insulin secretion (GSIS) increased after treatment, and GSIS was also inhibited by SDA plus U-73122 or BAPTA-AM. The presence of SDA antagonized palmitic acid-mediated MIN6 cells death. These findings indicate for the first time that SDA can promote GSIS in pancreatic β-cells via stimulation of GPR40-related signaling pathway (direct effect), and via antagonistic effect on long chain saturated fatty acid-mediated impairment (indirect effect).

本文旨在研究模拟微重力环境对骨髓间充质干细胞成骨分化的影响,重点研究mTOR信号通路是否介导这一过程.首先通过茜素红染色检验骨髓间充质干细胞的成骨分化情况;免疫荧光法对微丝和黏着斑蛋白Vinculin进行染色观察细胞骨架和细胞粘附性改变;蛋白免疫印迹实验检测mTOR信号通路关键信号分子p85 α,Akt,p-Akt,S6K1,RhoA等的表达水平变化.结果显示模拟微重力会抑制骨髓间充质干细胞的成骨分化,造成细胞微丝结构和分布异常,细胞形态改变,黏着斑数量减少.这种抑制与mTOR信号通路的改变有关.本研究为空间环境下骨质丢失的分子机制提供了理论基础.

国内外许多知名大学都十分重视高校人才的通识教育,更是将开展生命科学通识教育作为全面提高人才素质的重中之重.生命科学与人类的生存和发展面临的许多重大问题密切相关.在高校通识教育中重视生命科学专业知识的培养有利于非生命科学专业学生的知识结构更加合理全面,并且可以利用这些基础知识解决生活中的实际问题,提升全民素质和明辨是非的能力,是我国综合国力不断提升不可或缺的环节.编写适合学校特色教育的教程,探索和建立高效的教学体系是我们亟待解决的问题.

Simulated microgravity (SMG) was reported to affect tumor cell proliferation and metastasis. However, the underlying mechanism is elusive. In this study, we demonstrate that clinostat-modelled SMG reduces BL6-10 melanoma cell proliferation, adhesion and invasiveness in vitro and decreases tumor lung metastasis in vivo. It down-regulates metastasis-related integrin α6β4, MMP9 and Met72 molecules. SMG significantly reduces formation of focal adhesions and activation of focal adhesion kinase (FAK) and Rho family proteins (RhoA, Rac1 and Cdc42) and of mTORC1 kinase, but activates AMPK and ULK1 kinases. We demonstrate that SMG inhibits NADH induction and glycolysis, but induces mitochondrial biogenesis. Interestingly, administration of a RhoA activator, the cytotoxic necrotizing factor-1 (CNF1) effectively converts SMG-triggered alterations and effects on mitochondria biogenesis or glycolysis. CNF1 also converts the SMG-altered cell proliferation and tumor metastasis. In contrast, mTORC inhibitor, rapamycin, produces opposite responses and mimics SMG-induced effects in cells at normal gravity. Taken together, our observations indicate that SMG inhibits focal adhesions, leading to inhibition of signaling FAK and RhoA, and the mTORC1 pathway, which results in activation of the AMPK pathway and reduced melanoma cell proliferation and metastasis. Overall, our findings shed a new light on effects of microgravity on cell biology and human health.

Simulated-microgravity (SMG) promotes cell-apoptosis. We demonstrated that SMG inhibited cell proliferation/metastasis via FAK/RhoA-regulated mTORC1 pathway. Since mTORC1, NF-κB, and ERK1/2 signaling are important in cell apoptosis, we examined whether SMG-enhanced apoptosis is regulated via these signals controlled by FAK/RhoA in BL6-10 melanoma cells under clinostat-modelled SMG-condition. We show that SMG promotes cell-apoptosis, alters cytoskeleton, reduces focal adhesions (FAs), and suppresses FAK/RhoA signaling. SMG down-regulates expression of mTORC1-related Raptor, pS6K, pEIF4E, pNF-κB, and pNF-κB-regulated Bcl2, and induces relocalization of pNF-κB from the nucleus to the cytoplasm. In addition, SMG also inhibits expression of nuclear envelope proteins (NEPs) lamin-A, emerin, sun1, and nesprin-3, which control nuclear positioning, and suppresses nuclear positioning-regulated pERK1/2 signaling. Moreover, rapamycin, the mTORC1 inhibitor, also enhances apoptosis in cells under 1 g condition via suppressing the mTORC1/NF-κB pathway. Furthermore, the FAK/RhoA activator, toxin cytotoxic necrotizing factor-1 (CNF1), reduces cell apoptosis, restores the cytoskeleton, FAs, NEPs, and nuclear positioning, and converts all of the above SMG-induced changes in molecular signaling in cells under SMG. Therefore, our data demonstrate that SMG reduces FAs and alters the cytoskeleton and nuclear positioning, leading to enhanced cell apoptosis via suppressing the FAK/RhoA-regulated mTORC1/NF-κB and ERK1/2 pathways. The FAK/RhoA regulatory network may, thus, become a new target for the development of novel therapeutics for humans under spaceflight conditions with stressed physiological challenges, and for other human diseases.

Adoptive transfer of CD8+ T‐cells specific for tumor‐antigens is an attractive strategy for anti‐tumor therapy. In the present study, the subsets TA and TB were used to represent the population of CD8+ T cells generated by culturing the respective cells with irradiated dendritic cells (DCs) pulsed with ovalbumin (OVA) protein and transfected with adenoviral vector constructs as described.

Objective: To explore the effect of simulated microgravity (SMG) on the cytoskeleton and adhesion of mouse mesenchymal stem cells (MSCs), and to detect the expression of specific genes related to cell growth and differentiation under SMG. Methods: Fluorescence staining was used to detect the changes of cytoskeleton morphology and focal adhesion plaque distribution in MSCs. The expression of CyclinB1 and Vinculin was detected by Western blot. RNA arrays were used to detect the transcription of genes related to MSCs growth and differentiation. Results: Microtubules and microfilaments of MSCs altered significantly under microgravity, accompanied by decreased distribution of focal adhesion plaques. Western blot analysis indicates that SMG causes inhibition of Vinculin and CyclinB1 expression. The expression of genes stimulating osteoblast growth and MSCs' osteogenic differentiation, including Bmp4, Igf1, and Sox9 are down-regulated, and the expression of genes, including Csf2, Gdf5, Il1 beta and Sox2 that are involved in inhibition of osteogenic differentiation, or stimulating the formation of osteoclasts are up-regulated under SMG, which are detected by RNA PCR Array. These findings may explain the inhibition effects of SMG on MSCs proliferation and osteoblast differentiation.

Objective To study changes of blood testosterone and enzyme expression related to blood testosterone synthesis in male rats under simulated microgravity for a long time and explore the impact of microgravity on testicular testosterone synthesis.Methods 36 male Wistar rats were randomly divided into 6 groups(n=6) : tail suspended for 7 days group(S1),tail suspended for 14 days group(S2),tail suspended for 21 days(S3),control for 7 days group(C1),control for 14 days group(C2),control for 21days group(C3).Testosterone level in blood plasma was measured with enzyme linked immunosorbent assay(ELISA).Reverse transcription-polymerase chain reaction(RT-PCR) was used to determine the expression of steroidogenic acute regulatory protein(StAR),cholesterol side-cha in cleavage enzyme(P450scc),and 3beta-hydroxysteroid dehydrogenase(3β-HSD) mRNAs in testis of rats.Results Compared with the control groups,the weight of testis and the plasmatic testosterone level of the tail suspended groups decreased significantly(P0.01).The expression level of StAR,P450scc,3β-HSD mRNAs in tail suspended for 7 days group were significantly lower than those of the control group(P0.05).Compared with the control groups,the expression level of StAR mRNAs in tail suspended for 14 days group and tail suspended for 21 days group were not fond with significant difference(P0.05),but the expression level of P450scc and 3β-HSD mRNAs in tail suspended for 14 days group and tail suspended for 21 days group decreased significantly(P0.01).Conclusion The expression of P450scc,3β-HSD in testis decreases under simulated microgravity for a long time,which leads to the decreased testosterone synthesis and secretion of testicular leydig cell.

Human immunodeficiency virus type-1 (HIV-1)-specific dendritic cell (DC) vaccines have been used in clinical trials. However, they have been found to only induce some degree of immune responses in these studies. We previously demonstrated that the HIV-1 Gag-specific Gag-Texo vaccine stimulated Gag-specific effector CD8(+) cytotoxic T lymphocyte (CTL) responses, leading to completely protective, but very limited, therapeutic immunity. In this study, we constructed a recombinant adenoviral vector, adenovirus (AdV)4-1BBL, which expressed mouse 4-1BB ligand (4-1BBL), and generated transgenic 4-1BBL-engineered OVA-Texo/4-1BBL and Gag-Texo/4-1BBL vaccines by transfecting ovalbumin (OVA)-Texo and Gag-Texo cells with AdV4-1BBL, respectively. We demonstrate that the OVA-specific OVA-Texo/4-1BBL vaccine stimulates more efficient OVA-specific CTL responses (3.26%) compared to OVA-Texo-activated responses (1.98%) in wild-type C57BL/6 mice and the control OVA-Texo/Null vaccine without transgenic 4-1BBL expression, leading to enhanced therapeutic immunity against 6-day established OVA-expressing B16 melanoma BL6-10OVA cells. OVA-Texo/4-1BBL-stimulated CTLs, which have a CD44(+)CD62L(high) IL-7R(+) phenotype, are likely memory CTL precursors, demonstrating prolonged survival and enhanced differentiation into memory CTLs with functional recall responses and long-term immunity against BL6-10OVA melanoma. In addition, we demonstrate that OVA-Texo/4-1BBL-stimulated CTLs up- and downregulate the expression of anti-apoptosis (Bcl2l10, Naip1, Nol3, Pak7 and Tnfrsf11b) and pro-apoptosis (Casp12, Trp63 and Trp73) genes, respectively, by RT(2) Profiler PCR array analysis. Importantly, the Gag-specific Gag-Texo/4-1BBL vaccine also stimulates more efficient Gag-specific therapeutic and long-term immunity against HLA-A2/Gag-expressing B16 melanoma BL6-10Gag/A2 cells than the control Gag-Texo/Null vaccine in transgenic HLA-A2 mice. Taken together, our novel Gag-Texo/4-1BBL vaccine, which is capable of stimulating potent Gag-specific therapeutic and long-term immunity, may represent a new immunotherapeutic vaccine for controlling HIV-1 infection.

Dendritic cells (DCs), the most potent antigen-presenting cells have been extensively applied in clinical trials for evaluation of antitumor immunity. However, the efficacy of DC-mediated cancer vaccines is still limited as they are unable to sufficiently break the immune tolerance. In this study, we constructed a recombinant adenoviral vector (AdVIL-6) expressing IL-6, and generated IL-6 transgene-engineered DC vaccine (DCOVA/IL-6) by transfection of murine bone marrow-derived ovalbumin (OVA)-pulsed DCs (DCOVA) with AdVIL-6. We then assessed DCOVA/IL-6-stimulated cytotoxic T-lymphocyte (CTL) responses and antitumor immunity in OVA-specific animal tumor model. We demonstrate that DCOVA/IL-6 vaccine up-regulates expression of DC maturation markers, secretes transgene-encoded IL-6, and more efficiently stimulates OVA-specific CTL responses and therapeutic immunity against OVA-expressing B16 melanoma BL6-10OVA in vivo than the control DCOVA/Null vaccine. Moreover, DCOVA/IL-6-stimulated CTL responses were relatively maintained in mice with transfer of CD4+25+Foxp3+ Tr-cells, but significantly reduced when treated with anti-IL-6 antibody. In addition, we demonstrate that IL-6 down-regulates Foxp3-expression of CD4+25+Foxp3+ Tr-cells in vitro. Taken together, our results demonstrate that AdV-mediated IL-6 transgene-engineered DC vaccine stimulates potent CTL responses and antitumor immunity by counteracting CD4+25+ Tr immunosuppression via IL-6-induced Foxp3 down-regulation. Thus, IL-6 may be a good candidate for engineering DCs for cancer immunotherapy.

Objective: To observe the effect of simulated microgravity on cytoskeleton, proliferation, cell cycle, and apoptosis of osteoblasts. Methods: Osteoblasts were isolated and cultured from newborn rat cranial bones, and were cultured in the rotary clinostat for 24h, 48h, 72h, 96h, with control group in 1G condition. The distribution and direction of microtubules were observed by indirect immunofluorescence. The survival rate of osteoblasts was detected by MTT assay. And cell cycle and the percentages of apoptosis were measured through flow cytometry. Results: The microtubules distribution was changed significantly, which became obscured and showed no clear directions under simulated microgravity within 24h, but the growth of osteoblasts increased tinily. While cell proliferation were inhibited and the apoptosis rate increased, the proportion of G(1)/G(0) phase cells was higher, and S, G(2)+M phase cells were lower correspondingly when cells were under simulated microgravity for more than 48h. With the prolonged rotation time, the differences became more obvious. Conclusion: Simulated microgravity has many effects on rat osteoblasts structure and growth. Those effects may interaction to influence the functions of osteoblasts, leading to bone loss under microgravity condition.

BACKGROUND AND OBJECTIVE:The basic structure of salicylaldehyde-amino acid Schiff base compounds includes a C=N chemical bond. These compounds show significant antitumor activities in vitro when combined with a metal ion. This study investigated the effects and possible mechanisms of four salicylaldehyde-amino acid Schiff base copper ternary coordination compounds on the proliferation of human gastric cancer cell line BGC823.METHODS:The BGC823 cells were treated with the four compounds (6B, 7B, 6P, and 7P). Cell proliferation was detected by MTT assay. Apoptosis and changes in the cell cycle were analyzed by flow cytometry. DNA damage was observed using a DNA ladder assay. The expression of p53 protein was determined by immunocytochemistry.RESULTS:The proliferation of BGC823 cells was significantly inhibited by the four compounds and the effect was concentration-dependent. The half maximal inhibitory concentration (IC50) of 6B, 7B, 6P, and 7P for BGC823 cells were 18.10, 27.50, 3.61, and 3.45 micromol/L, respectively. Flow cytometry showed the four drugs induced apoptosis in BGC823 cells, which was confirmed by DNA ladder experiments. Flow cytometry also detected changed phases in the cell cycle from treatment with the compounds. The percent of cells in the G(0)/G(1) phase decreased and that of cells in the G1/S and G(2)/M phases increased, indicating that S-and G2-phase blockages exist. As shown by immunocytochemistry, the expression of p53 decreased in BGC823 cells treated with the four drugs, indicating the involvement of the p53 pathway to BGC823 cell apoptosis.CONCLUSIONS:The four compounds showed significant activities on restraining proliferation of BGC823 cells in vitro, induced apoptosis, and caused changes in the cell cycle. This may be related to the downregulation of p53.

It is of great significant to deeply understand the life progress and promote medicine developments using appropriate techniques to characterize interaction between biomolecules. Microfluidic chip electrophoresis technique which combines microfluidic chip with capillary electrophoresis possesses many advantages including rapid, high performance, high throughput, low sample consumption and easy of integration, etc. It has already demonstrated great potential just in the early stage of application. In this paper, the separation mode, analysis methods and detection techniques in chip-CE biological binding constant and binding mechanism are reviewed respectively. The chip-CE is also simply compared with micro-array chip biomolecular interaction analysis. Finally, the development prospects and present situations in chip-CE are analyzed.

Aqueous nanoparticle suspension of fullerene and its derivatives are currently attracting much attention. To determine the effects of aqueous nanoparticle suspension of a mono-methanophosphonate fullerene and bis-methanophosphonate fullerene (denoted as n-MMPF and n-BMPF, respectively) on the activities of DNA restrictive endonucleases, plasmid pEGFP-N1 was cleaved at a single but differently restrictive site by EcoR I, BamH I, and isozymes Cfr9 I and Xma I, respectively. Both n-MMPF and n-BMPF inhibited the activity of EcoR I, while n-BMPF exhibited stronger inhibition than n-MMPF. Addition of n-BMPF into reaction mixtures inhibited the activities of all the four enzymes, and IC50 values for EcoR I, BamH I, Cfr9 I and Xma I were 4.3, >30, 11.7 and 8.3 μmol/L, respectively. When EcoR I was completely inhibited by n-BMPF, addition of excess amounts of pEGFP-N1 could not produce the product linear plasmid; however, increase of EcoR I amounts antagonized EcoR I inhibition of n-BMPF. Two scavengers of reactive oxygen species (ROS), mannitol and sodium azide at the concentrations of 2–10 mmol/L, did not reverse inhibition of n-BMPF, implying that this inhibition probably is not correlated to ROS. These results suggested that aqueous nano-fullerenes might act as inhibitors of DNA restrictive endonucleases.

This report aimed to describe a novel type of core-shell-structured microcapsules suitable for spontaneous loading of anticoagulant heparin. Chitosan (CS) microspheres were fabricated by a sodium sulfate-based precipitation process. The microspheres were approximately I pm in size and applied as templates for microcapsules prepared by the layer-by-layer (LbL) self-assembly technique. Polyelectrolytes including polyanion poly(styrene sulfonate) and polycation CS were alternately deposited on CS microsphere templates, monitored by flow cytometry and zeta potential analysis. Scanning electron microscopy, confocal laser scanning microscopy, fluorescence microscopy, flow cytometry and laser particle size analysis were used to characterize the microcapsules. The resulted microcapsules were about I pm in average diameter, and allowed spontaneous loading of heparin through electrostatic interaction, with the encapsulation efficiency and loading capacity of 74.4% and 10.0%. respectively. Moreover, heparin could be released from the microcapsules in phosphate buffered saline at pH 7.4. It is suggested that the type of microcapsules may provide a new and effective system of heparin delivery for pharmaceutical use. (C) 2008 Elsevier B.V. All rights reserved.

富勒烯纳米颗粒水悬液的生物学效应正在引起人们的极大关注.采用具有EcoRⅠ、BamHⅠ、Cfr9Ⅰ和XmaⅠ单一酶切位点的pEGFP-N1超螺旋型质粒为底物,检测了单加成亚甲基富勒烯[60]二膦酸四乙酯（mono-methanophosphonate fullerene,MMPF）和二加成亚甲基富勒烯[60]二膦酸四乙酯（bis-methanophosphonate fullerene,BMPF）的纳米水悬液（分别表示为n-MMPF和n-BMPF）对各种DNA限制性内切酶的抑制作用.实验发现,n-MMPF和n-BMPF均对EcoRⅠ有抑制作用,但后者的作用更强些.加入n-BMPF后,对BamHⅠ酶切反应的半抑制浓度IC50值大于30μmol/L,而对EcoRⅠ的半抑制浓度IC50值仅为4.3μmol/L,对同工酶Cfr9Ⅰ和XmaⅠ的半抑制浓度IC50值分别为11.7和8.3μmol/L.当EcoRⅠ酶切反应完全被n-BMPF抑制时,在反应体系中增加底物pEGFP-N1的量,并不能观察到酶切产物线型质粒,但是在酶切体系中增加酶的量则能拮抗n-BMPF的作用.两种活性氧清除剂甘露醇和叠氮化钠在浓度为2~10mmol/L时,不能拮抗n-BMPF的作用,说明n-BMPF的抑制活性与活性氧无关.这些结果首次表明,富勒烯纳米颗粒水悬液具有作为DNA限制性内切酶抑制剂的生物活性.

Novel biological activities of a fullerene-oligonucleotide conjugate (FONC) were examined in the present report. A new FONC containing a complementary sequence to a specific region of the beta-actin cDNA was synthesized. We found that the FONC at a low concentration (10(-6)M) could specifically inhibit PCR-amplification of the beta-actin cDNA by inhibiting the activities of both Taq DNA polymerase and the cDNA template. This inhibition appeared to be mediated by reactive oxygen species (ROS). The FONC also exhibited the ability of antagonizing the enzymatic activity of an engineered nuclease, exonuclease I (Exo I). Our data provided some valuable evidences on the prospective use of FONC in the antisense strategy for gene silencing.

Objective To study the mechanism of decreased secretion of testosterone in male rats under short-term simulated microgravity with examining mRNA of genes expression related to testosterone synthesis. Methods A tail-suspended model of rat with its inguinal canal ligation to simulate microgravity was used. Testosterone level in blood plasma was measured with enzyme-linked immunosorbent assay (ELISA). Reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the expression of steroidogenic acute regulatory protein (StAR), cytochrome P450-17α-hydroxylase (P450c17), and 3β-hydroxysteroid dehydrogenase (3β-HSD) mRNAs in testis of rats. Results After 7 d tail-suspension, the weight of testis and the plasmatic testosterone level of tail-suspended rats both with or without inguinal canal ligation decreased significantly compared with controls (P<0.01). The expression level of StAR, P450c17, 3β-HSD mRNAs in testis were significantly lower than those of the control group (P<0.05). Conclusion The expression of StAR, P450c17, 3β-HSD in testis decreases under short-term simulated microgravity, which leads to the decreased testosterone synthesis and secretion.