Remarkably Reduced Expression of FoxO3a in Metaplastic Colorectum, Primary Colorectal Cancer and Liver Metastasis

The forkhead family members of transcription factors （FoxOs） are expected to be potential cancer-related drug targets and thus are being extremely studied recently. In the present study, FoxO3a, one major member of this family, was identified to be down-regulated in colorectal cancer through mi- cro-array analysis, which was confirmed by RT-PCR and Western blot in 28 patients. Moreover, immu- nohistochemistry （IHC） showed that the expression levels of FoxO3a were remarkably reduced in 99 cases of primary colorectal cancer, liver metastasis, and even in metaplastic colorectal tissue. IHC also revealed an exclusion of FoxO3a from the nucleus of most cells of tumor-associated tissues. Silencing FoxO3a by siRNA led to elevation of G2-M phase cells. We conclude that the downregulation of FoxO3a may greatly contribute to tumor development, and thus FoxO3a may represent a novel thera- peutic target in colorectal cancer.

Pathogenicity of Rabies Viruses Isolated in China: Two Fixed Strains and a Street Strain

Objective To investigate the virulence characteristics of two fixed strains （CTN and aG） and a street strain （HNIO） of rabies viruses isolated in China, Methods ICR mice of different age groups were via the intracracerebral （i.c.） or intramuscular （i.m inoculated with CTN, aG and HN10 rabies virus strains ） routes, and observed for 20 days. Results The CTN strain was pathogenic to 7-day-old suckling mice that received i.c. inoculations and 3-day-old suckling mice that received i.m. inoculations. The aG strain was pathogenic to 4-week-old mice that received i.c. inoculations and 7-day-old suckling mice that received i.m. inoculations. The HN10 strain was pathogenic to mice of all age groups via both inoculation routes. In moribund mice, the viruses had spread to most regions of the brain. The CTN and HN10 strains had similar dissemination patterns in the brain; both viral antigens could be found in the dentate gyrus （DG）, whereas few viral antigens were present in the DG from specimens that had been infected with the aG strain. Conclusion A comprehensive sequence analysis of the G protein suggested that differences in gene sequences may be responsible for producing strain-specific differences in pathogenicity and distribution in the brain.

Effects of Rapamycin on the Differentiation and Function of Macrophages In Vitro

Macrophages have been generated from bone marrow progenitor cells （BMPCs） with macrophage colony-stimulating factor （M-CSF）. Rapamycin （rapa） is an immunosuppressive drug, which could prevent renal graft rejection and inhibit tumor growth to yield antiproliferative activity in a variety of malignancies. However, the direct effect of rapa on the development of macrophages is unknown. In this study, we explored the direct effect of rapa on the differentiation and function of macrophages differentiated from mouse BMPCs in vitro in the presence of M-CSF. The experimental data showed that rapa prevented the differentiation of macrophagcs by down-regulating CD80 and CD86 expression but upregulating F4/80 expression, as well as by reducing the capacity of differentiated macrophages to stimulate lymphocyte proliferation in the allogeneic mixed lymphocyte reaction. Furthermore, the phagocytic capacity of differentiated macrophages was significantly reduced by rapa. Therefore, rapa may directly inhibit macrophage differentiation and function, which may have been one of the major targets for rapa to mediate its immunosuppressive properties.

Inhibition of T Cell and Stimulation of B Cell Proliferation by Restraint Stress Mediated by Voltage-Gated Potassium Channel 1.3 Expression

Our previous study has showed that restraint stress inhibits T cell proliferation. Kv1.3 plays a key role in the lymphocyte activation process. Here, we investigate the effects of restraint stress on murine splenic T and B cell proliferation and the role of Kv1.3 in the process. 3H-TdR incorporation is used to determine changes in splenocyte proliferation stimulated by Con A or LPS between control and restraint stress groups. The data shows that restraint stress inhibits T cell and enhanced B cell proliferation. Data from RT-PCR and Western blotting shows that Kv1.3 gene and protein levels are downregulated in T cells and upregulated in B cells in stressed mice. To examine a possible cause-and-effect relationship between Kv1.3 and stress-affected lymphocyte proliferation, we employ various Kv1.3 specific blockers (quinine, 4-AP and TEA) to determine K+ channel function under restraint stress. The data shows that Kv1.3 blockers reverse the decreased T cell proliferation and increase B cell proliferation induced by restraint stress. These results indicate that Kv1.3 mediates restraint stress-induced modulation of T/B lymphocyte proliferation.

Adipose-derived mesenchymal stem cell transplantation promotes adult neurogenesis in the brains of Alzheimer's disease mice

In the present study, we transplanted adipose-derived mesenchymal stem cells into the hippo-campi of APP/PS1 transgenic Alzheimer＇s disease model mice. Immunofluorescence staining revealed that the number of newly generated （BrdU＋） cells in the subgranular zone of the dentate gyrus in the hippocampus was signiifcantly higher in Alzheimer＇s disease mice after adipose-de-rived mesenchymal stem cell transplantation, and there was also a significant increase in the number of BrdU＋/DCX＋neuroblasts in these animals. Adipose-derived mesenchymal stem cell transplantation enhanced neurogenic activity in the subventricular zone as well. Furthermore, adipose-derived mesenchymal stem cell transplantation reduced oxidative stress and alleviated cognitive impairment in the mice. Based on these ifndings, we propose that adipose-derived mes-enchymal stem cell transplantation enhances endogenous neurogenesis in both the subgranular and subventricular zones in APP/PS1 transgenic Alzheimer＇s disease mice, thereby facilitating functional recovery.

Endocytic regulation of TGF-β signaling

转变生长因素 -- 尾(发信号的 TGF- 尾) 紧被调整在不同细胞和纸巾保证它的合适的生理的功能。象另外的房间表面受体一样， TGF- 尾受体被使内在化进房间，并且这个过程在 TGF- 尾发信号起一个重要规章的作用。当 TGF- 尾 endocytosis 能被钾弄空和 GTPase 缺乏的 dynamin K44A 异种堵住， TGF- 尾受体是经由 clathrin 涂的泡的 endocytosed，这很好被记录当 TGF- 尾 endocytosis 能被钾弄空和 GTPase 缺乏的 dynamin K44A 异种堵住。TGF- 尾受体可以也经由充满胆固醇的膜 microdomain 类脂化合物 rafts/caveolae 进入房间并且在 caveolin-1-positive 泡被发现。尽管受体 endocytosis 不为 TGF- 尾是必要的发信号，调停 clathrin 的 endocytosis 被显示了支持 TGF- 尾 - 导致的 Smad 激活和 transcriptional 回答。类脂化合物 rafts/caveolae 广泛地被认为是为 G 联合蛋白质的受体和酷氨酸 kinase 受体表明中心，但是他们被显示便于 TGF- 尾受体并且因此的降级 TGF- 尾发信号的转弯。这评论在 TGF- 尾发信号的调整总结 TGF- 尾受体 endocytosis，位于这个过程下面的可能的机制，和 endocytosis 的角色的当前的理解。

Monomeric type I and type III transforming growth factor-β receptors and their dimerization revealed by single-molecule imaging

转变生长因素 -- 尾(TGF- 尾) 与二 transmembrane serine/threonine kinase 受体，类型 II (T 尾 R II ) 和类型绑我受体(T 尾 R 我) ，并且一附件受体，类型 III 受体(T 尾 R III ) ，到越过房间膜的 transduce 信号。以前的生物化学的研究建议了那 T 尾 R 我和 T 尾 R III 被先存在 homo-dimers。用到图象绿色的单个分子的显微镜学荧光灯标记蛋白质的膜蛋白质，第一次，我们表明了那 T 尾 R 我和 T 尾 R III 能在低表达式水平作为单体存在。在 TGF-尾 1 刺激之上，我跟随的 T 尾 R 为激活的一般导致 ligand 的受体 dimerization 模型，而是这个过程是 T 尾 R II 依赖。non-kinase 受体 T 尾 R III 的 monomeric 地位面对 TGF-尾 1 是未改变的。随受体表示的增加，两 T 尾 R 我和 T 尾 R III 能在房间表面上被装配进 dimers。

PTEN,a general negative regulator of cyclin D expression

在相同(PTEN ) 的有十的 tumor-suppressor 磷酸酶经常在许多恶意被变异并且是最好学习的肿瘤之一压制或基因[1,2 ] 。PTEN，类脂化合物和蛋白质双磷酸酶，在胚胎发育，房间生长， apoptosis 和房间移植起一个重要作用。PTEN 的著名功能是作为 PI_3 kinase (PI3K ) 的一个否定管理者工作的 phosphatidylinositol-3 (PI_3 )-phosphatase, 小径。PTEN 由 modulating 调整 G1 -S 转变，这很好被建立 cyclin D1and p27^(Kip1 ) 的表示。

Redox status of thioredoxin-1 （TRX1） determines the sensitivity of human liver carcinoma cells （HepG2） to arsenic trioxide-induced cell death

细胞内部的氧化还原作用动态平衡在决定肿瘤房间的敏感到导致药的 apoptosis 起一个关键作用。这里，我们调查了 thioredoxin-1 (TRX1 ) 的角色，氧化还原作用规定的一个关键部件，在砷三氧化物(作为(2 ) O (3 )) 导致的 apoptosis。在 HepG ( 2 )房间的野类型的 TRX1 的在表示上导致了抑制当( 2 ) O ( 3 )导致了细胞色素 c ( cyto c )，释放， caspase 激活和 apoptosis ，并且由 RNAi 的 TRX1 表示的绒毛规定敏化 HepG ( 2 )房间到当( 2 ) O ( 3 )导致了 apoptosis 。有趣地，到重量的单位(32/35 ) 的从 Cys (32/35 ) 的 TRX1 的活跃地点的变化从一个 apoptotic 保护者把这个分子变换成一个 apoptotic 倡导者。以理解这变换的机制，我们从老鼠肝使用了孤立的线粒体并且发现了野类型的 TRX1 能保护的那重组体从 apoptotic 的线粒体变化。相反， TRX1 的变异的形式独自得到了线粒体相关的 apoptotic 变化，包括 mitochondrial 渗透转变毛孔(mPTP ) 洞， mitochondrial 膜潜力的损失，和 cyto 从线粒体的 c 版本。这些 apoptotic 效果被 cyclosporine A (CsA ) 禁止，显示指向到 mPTP 的那变异的 TRX1。到由 2,4-dinitrochlorobenzene (DNCB ) 的氧化形式体内的从它的减少的形式的 TRX1 的改变， TRX reductase 的一个特定的禁止者，也敏化的 HepG (2 ) 房间到当(2 ) O (3 ) 导致了 apoptosis。这些数据建议 TRX1 由任何一个变化在由堵住 cyto c 版本调整 apoptosis，并且在 TRX1 的激活起一个中央作用或活跃地点半胱氨酸的氧化可以敏化肿瘤房间到当(2 ) O (3 ) 导致了 apoptosis。

Thymic epithelial progenitor cells and thymus regeneration: an update

胸腺为 T 房间开发和成熟提供必要微型环境。Thymic 上皮的房间(侦探) 它是 thymic 填写了外皮的上皮的房间(cTECs ) 和 thymic 髓的上皮的房间(mTECs ) ，很好被记录了为这些紧调整的过程批评。侦探的普通祖先房间是否能产生 cTECs 和 mTECs，长是争论的。大进步被取得了在最近的年里描绘普通侦探祖先房间。我们此处在胸腺新生象这些祖先房间一样关于侦探区别讨论唯一的起源范例。

IL-17RD （Sef or IL-17RLM） interacts with IL-17 receptor and mediates IL-17 signaling

Interleukin-17 (IL-17 或 IL-17A ) 生产是 TH17 房间的一个特点，贡献多重自体免疫、煽动性的疾病的致病的 CD4+ T 淋巴细胞的一个新唯一的系。IL-17 受体(IL-17R 或 IL-17RA ) 为 IL-17 生物活动是必要的。新兴的数据建议 heteromeric 或 homomeric 受体建筑群的形成为 IL-17 发信号被要求。这里，我们证明孤儿受体 IL-17RD (Sef，类似的表示到 FGF 基因或 IL-17RLM ) 被联系并且有 IL-17R 的 colocalized。重要地， IL-17RD 调停 IL-17 发信号，用一个酶记者评估了由 24p3 的本国的倡导者开车， IL-17 目标基因。另外，主导否定地缺乏细胞内部的领域的 IL-17RD 异种压制 IL-17R-mediated IL-17 发信号。而且，象 IL-17R 一样的 IL-17RD 与 TRAF6 被联系，一个 IL-17R 下游的分子。这些结果显示 IL-17RD 是表明建筑群的 IL-17 受体的部分，因此为通过 heteromeric 或 homomeric 受体建筑群发信号的 IL-17 提供新奇证据。

Smad2 mediates Activin/Nodal signaling in mesendoderm differentiation of mouse embryonic stem cells

尽管发信号的 Activin/Nodal 调整人的胚胎的茎(ES ) 的 pluripotency 细胞，这个发信号怎么在老鼠 ES 细胞行动，仍然保持大部分不清楚。调查这，我们证实了房间拥有活跃调停 Smad2 的 Activin/Nodal 发信号的那老鼠 ES 并且发现调停 Smad2 的 Activin/Nodal 发信号为自强维护是非必需的，但是向 mesendoderm 系为合适的区别被要求。到进内在的机制的获得卓见，联系 Smad2 的基因被染色体宽的染色质 immunoprecipitation 薄片分析识别。结果证明在 Smad2 绑定和 Activin/Nodal 发信号调整之间有 transcriptional 关联，并且发展相关的基因在 Smad2 固定的目标之中被充实。我们进一步在 Activin/Nodal-Smad2 小径下游地行动的老鼠 ES 房间的 mesendoderm 区别作为一个关键播放器识别了 Tapbp。一起拿，我们的调查结果建议发信号的调停 Smad2 的 Activin/Nodal 通过相应发展管理者表示的直接调整安排鼠标 ES 房间的 mesendoderm 系承诺。

Phosphorylation of tau protein over time in rats subjected to transient brain ischemia

Transient brain ischemia has been shown to induce hyperphosphorylation of the micro- tubule-associated protein tau. To further determine the mechanisms underlying these processes, we investigated the interaction between tau, glycogen synthase kinase （GSK）-313 and protein phos- phatase 2A. The results confirmed that tau protein was dephosphorylated during brain ischemia; in addition, the activity of GSK-3β was increased and the activity of protein phosphatase 2A was de- creased. After reperfusion, tau protein was hyperphosphorylated, the activity of GSK-3β was de- creased and the activity of protein phosphatase 2A remained low. Importantly, the interaction of tau with GSK-3β and protein phosphatase 2A was altered during ischemia and reperfusion. Lithium chloride could affect tau phosphorylation by regulating the interaction of tau with GSK-3β and pro- tein phosphatase 2A, and improve learning and memory ability of rats after transient brain ischemia. The present study demonstrated that it was the interaction of tau with GSK-3β and protein phos- phatase 2A, rather than their individual activities, that dominates the phosphorylation of tau in tran- sient brain ischemia. Hyperphosphorylated tau protein may play an important role in the evolution of brain injury in ischemic stroke. The neuroprotective effects of lithium chloride partly depend on the inhibition of tau phosphorylation during transient brain ischemia.

In vitro biocompatibility of three chitosan/polycation composite materials for nerve regeneration

BACKGROUND：It has been reported that chitosan nerve conduits could support axon elongation and improve relevant function during in vivo nerve regeneration. OBJECTIVE： To investigate in vitro biocompatibility of three novel, chitosan/polycation composite materials for nerve regeneration in cultured mouse Schwann cells and PC12 cells. DESIGN, TIME AND SETTING： The observational, control experiments for nerve tissue engineering were performed at the Department of Biological Sciences and Biotechnology of Tsinghua University from August 2007 to January 2008. MATERIALS： Mouse Schwann cells were isolated from the sciatic nerve of 5–7-day-old BALB/C mice. PC12 cells were purchased from the American Type Culture Collection （ATCC, USA）. Chitosan was purchased from Tsingdao Haisheng Co., China. Poly-L-lysine hydrochloride （PLL）, polyethyleneimine （PEI） poly-L-ornithine hydrobromide （POR）, and S-100 antibody was purchased from Sigma Chemical Co., USA. Cell Counting Kit-8 （CCK-8） was purchased from Dojindo Chemical Co., Japan. METHODS： Three chitosan/polycation composite materials for nerve regeneration （PLL-0.25, PEI-0.25, and POR-0.25） were produced by blending chitosan with 0.25% （w/w） poly-L-lysine, polyethyleneimine, and poly-L-ornithine. Pure chitosan was utilized as the control. After 3 days of culture, the morphology of mouse Schwann and PC12 cells cultured on all substrates was observed with an inverted phase contrast microscope. Mouse Schwann cells were stained by immunofluorescence labeling S-100 protein and nuclei, followed by identification with a confocal laser-scanning microscope. The amount of proliferating mouse Schwann and PC12 cells was determined by CCK-8 after 1, 3, and 5 days in culture. The level of PC12 cell differentiation on all substrates was assessed by measuring neurite length at 1, 3, and 5 days after seeding. MAIN OUTCOME MEASURES： Morphology and amount of proliferation of mouse Schwann cells and PC12 cells cultured on chitosan and three polycation-modified materials, as well as amount of differentiation in PC12 cells on these substrates. RESULTS： （1） Morphology of mouse Schwann cells and PC12 cells on all substrates： after 3 days in culture on three different chitosan/polycation composite substrates, Schwann cells were connected to each other and exhibited greater proliferation, compared to the chitosan control. In particular, on PLL-0.25 and POR-0.25 substrates, some cells congregated and nearly reached confluence. The PC12 cells on chitosan substrate, after 3 days in culture, maintained a round shape; few exhibited a bipolar shape and began to form neurite extensions. However, on PLL-0.25 and POR-0.25 substrates, most PC12 cells displayed a bipolar shape with obvious neurite outgrowth, and almost grew as an adherent, spreading monolayer. （2） Proliferation of mouse Schwann cells and PC12 cells on all substrates： on the first day, Schwann cell proliferation on the three composite substrates was significantly greater than the cells on chitosan control （P 〈 0.01）. After 3 and 5 days in culture, PLL-0.25 and POR-0.25 substrates resulted in greater cell proliferation when compared to pure chitosan （P 〈 0.01）. On the third and fifth day in culture PC12 cell proliferation on PLL-0.25 and POR-0.25 was significantly greater than on chitosan substrate （P 〈 0.01）. （3） Differentiation of PC12 cells on all substrates： at all time points, the average neurite length of cells cultured on composite materials was significantly longer than on chitosan control （P 〈 0.05-0.01）. Cells on PLL-0.25 exhibited the longest average neurite length at days 3 and 5. CONCLUSION： Mouse Schwann cells and PC12 cells exhibit in vitro biocompatibility with poly-L-lysine-and poly-L-ornithine-modified substrates, which indicates that these substrates could serve as suitable substrates for peripheral nerve regeneration.

pH Dependence of Chlorophyll States, Protein Structures and Function of the PSII Membranes

The effect of varying pH on the photosystem II (PSII) membrane was studied using absorption and steady state fluorescence spectroscopy, and using a variable fluorescence technique. pH variations induced significant changes in the chlorophyll states of the PSII membrane, but no effect was seen on the chlorophyll fluorescence parameter F ′ v/ F ′ m. For acidic pH conditions, protein structures of the PSII membrane were slightly altered, whilst at alkaline pH levels, large changes in the protein structure of the PSII membrane were detected. The results indicate that the microenvironment around Cys in the PSII membrane is very susceptible to alkaline pH conditions, and that in the acid (4≤pH<7) and alkaline (9≥pH>7) regions, pH variation has no effect on the protein structures of the PSII reaction center (RC).

Increase in the Transition Enthalpy of Fibrinogen upon Adsorption onto Hydroxyapatite

The increase of the protein transition enthalpy upon adsorption onto biomedical material surfaces was observed by measuringthe differential scanning calorimetry(DSC)traces of bovine fibrinogen adsorbed onto a hydroxyapatite surface.The mechanism causing the transition enthalpy increase upon adsorption was clariHed by using DSC measurements of bovine fibrinogen for different ionic strength and sodium dodecyl sulfate concentrations.The fesu7ts surest that the increased Hbrinogen transition enthalpy may be attributed to the electrostatic interactions between the carboxyl of the D domains and the calcium loci of hydroxyapatite,which may result in a more compact protein structure.

Structure of unliganded membrane-proxima domains FN4-FN5-FN6 of DCC

Dear Editor, Deleted in colorectal cancer （DCC） is a single pass transmembrane glycoprotein that was originally identified in humans as a candidate tumor suppressor （Fearon et al., 1990）. DCC belongs to the immunoglobulin superfamily, and the extracellular fragment is composed of four immunoglobu- lin-like （Ig-like） domains followed by six fibronectin type III （FN） domains. DCC plays a pivotal role in axon guidance by mediating a combination of attractive and repulsive effects through interactions with the diffusible guidance cue,

Generation of a monkey with MECP2 mutations by TALEN-based gene targeting

Gene editing in model organisms has provided critical insights into brain development and diseases. Here, we report the generation of a cynomolgus monkey （Macaca fascicularis） carrying MECP2 mutations using transcription activator-like effector nucleases （TALENs）-mediated gene targeting. After injecting TALENs mRNA into monkey zygotes achieved by in vitro fertilization and embryo transplantation into surrogate monkeys, we obtained one male newborn monkey with an MECP2 deletion caused by frame- shifting mutation in various tissues. The monkey carrying the MECP2 mutation failed to survive after birth, due to either the toxicity of TALENs or the critical requirement of MECP2 for neural development. The level of MeCP2 protein was essentially depleted in the monkey＇s brain. This study demonstrates the feasibility of introducing genetic mutations in non-human primates by site-specific gene-editing methods.

Neural Stem Cell Affinity of Chitosan and Feasibility of Chitosan-Based Porous Conduits as Scaffolds for Nerve Tissue Engineering

Neural stem cells （NSCs） are currently considered as powerful candidate seeding cells for regeneration of both spinal cords and peripheral nerves. In this study, NSCs derived from fetal rat cortices were co-cultured with chitosan to evaluate the cell affinity of this material. The results showed that NSCs grew and proliferated well on chitosan films and most of them differentiated into neuron-like cells after 4 days of culture. Then, molded and braided chitosan conduits were fabricated and characterized for their cytotoxicity, swelling, and mechanical properties. Both types of conduits had no cytotoxic effects on fibroblasts （L929 cells） or neuroblastoma （Neuro-2a） cells. The molded conduits are much softer and more flexible while the braided conduits possess much better mechanical properties, which suggests different potential applications.