Nerve growth factor promotes in vitro proliferation of neural stem cells from tree shrews

Neural stem cells promote neuronal regeneration and repair of brain tissue after injury,but have limited resources and proliferative ability in vivo.We hypothesized that nerve growth factor would promote in vitro proliferation of neural stem cells derived from the tree shrews,a primate-like mammal that has been proposed as an alternative to primates in biomedical translational research.We cultured neural stem cells from the hippocampus of tree shrews at embryonic day 38,and added nerve growth factor（100 μg/L） to the culture medium.Neural stem cells from the hippocampus of tree shrews cultured without nerve growth factor were used as controls.After 3 days,fluorescence microscopy after DAPI and nestin staining revealed that the number of neurospheres and DAPI/nestin-positive cells was markedly greater in the nerve growth factor-treated cells than in control cells.These findings demonstrate that nerve growth factor promotes the proliferation of neural stem cells derived from tree shrews.

Regeneration of islet β-cells in tree shrews and rats

Backgroud: Current understanding of injury and regeneration of islet β-cells in diabetes is mainly based on rodent studies. The tree shrew is now generally accepted as being among the closest living relatives of primates, and has been widely used in animal experimentation. However, there are few reports on islet cell composition and regeneration of β-cells in tree shrews.Methods: In this study, we examined the changes in islet cell composition and regeneration of β-cells after streptozotocin(STZ) treatment in tree shrews compared with Sprague-Dawley rats. Injury and regeneration of islet β-cells were observed using hematoxylin and eosin(HE) staining and immunohistochemical staining for insulin, glucagon, somatostatin and PDX-1.Results: Our data showed that in rats islet injury was most obvious on day 3 after injection, and islet morphologies were significantly restored by day 21. Regeneration of islet β-cells was very pronounced in rats, and mainly involved regeneration of centro-acinar cells and transformation of extra-islet ductal cells. In tree shrews, the regeneration of islet β-cells was not as significant. On days 3 and 7, only scattered regenerated cells were observed in the remaining islets. Further, no regeneration of centro-acinar cells was observed.Conclusion: The results suggest that the repair mechanism of islet β-cells in tree shrews is similar to that of humans.

Age-related changes of corneal endothelial cell in healthy Chinese tree shrew measured by non-contact specular microscope

AIM：To determine the impact of age on the morphology of endothelial cells and central corneal thickness（CCT） in Chinese tree shrew.METHODS：One-hundred and twenty eyes of 60 healthy Chinese tree shrews were studied.Based on age,the tree shrews were divided into four groups.After general anesthesia,the images of endothelium were acquired using non-contact specular microscope Topcon 3000 P.Eight parameters of corneal endothelial cells were measured by built-in software,including CCT,endothelial cell density（ECD）,percent hexagonality（HG%）,coeffi cient of variability（CV）,size of minimal cell（Smin）,size of maximal cell（Smax）,average cells size（Savg） and size standard deviation（Ssd）.Data were analyzed using STATA software.The differences of eight parameters among groups and correlations with age were analyzed.RESULTS：In all studied animals,the average CCT was 2 4 9.6 ± 2 .29 μ m（202-301 μm）,ECD was 308 0.72 ± 460.76 cells/mm^2（1239.6-4047.6 cells/mm^2） and CV was 29.10±7.60（13.6-54.6）.CV was significantly different among different groups（P〈0.001）.Strong correlation with age was found in ECD,Smax,Savg,Ssd and CV.CONCLUSION：Cornea of Chinese tree shrews had half CCT of human cornea and similar ECD,CV and size of corneal endothelial cells.Young adult tree shrews had higher ECD,HG% and low CV.ECD,Smax,Savg,Ssd and CV correlated with age signifi cantly.

Photoelectric Characterization of Dye Sensitized Solar Cells Using Natural Dye from Pawpaw Leaf and Flame Tree Flower as Sensitizers

Natural dyes from flame tree flower, Pawpaw leaf and their mixtures were used as sensitizers to fabricate dye-sensitized solar cells (DSSC). The photoelectrochemical performance of the Flame tree flower dye extract showed an open-circuit voltage (VOC) of 0.50 V, short-circuit current density (JSC) of 0.668 mA/cm2, a fill factor (FF) of 0.588 and a conversion efficiency of 0.20%. The conversion efficiency of the DSSCs prepared by pawpaw leaf extract was 0.20%, with VOC of 0.50 V;short-circuit current density, JSC of 0.649 mA/cm2 and FF of 0.605. The conversion efficiency for the flame tree flower and pawpaw leaf dye mixture was 0.27%, with VOC of 0.518 V, JSC of 0.744 mA/cm2 and FF of 0.69. Although the conversion efficiencies, Jsc and the Voc of the prepared dye cells were lower than the respective 1.185%, 7.49 mA/cm2 and 0.64V reported for ruthenium, their fill factors (FF) were higher than that of ruthenium (0.497). It was also observed that both the short-circuit current density and the fill factors of the cells were enhanced using mixed dye.

高活性脐带间充质干细胞干预老年树鼩衰老脾脏的作用与机制

背景:脾脏具有储血、造血和免疫功能,随着年龄增长,脾脏结构退变、功能衰退引起免疫系统功能受损,进而加速机体衰老进程,而高活性脐带间充质干细胞治疗树鼩脾脏衰老尚未见报道。目的:探讨高活性脐带间充质干细胞对树鼩脾脏衰老的干预作用及机制。方法:从剖腹产的新生树鼩脐带组织中分离、培养和获得高活性脐带间充质干细胞,三系分化试剂盒检测成脂、成骨、成软骨分化能力,流式细胞术检测细胞周期和表面标志物。以感染复数值分别为100,120,140,160,180,200的吉凯基因绿色荧光蛋白转染第2代高活性脐带间充质干细胞,筛选最佳转染条件;转染后的第4代高活性脐带间充质干细胞尾静脉输注给老年治疗组树鼩,青年对照组和老年模型组不予特殊处理,治疗4个月时取脾脏组织,苏木精-伊红染色观察脾脏组织结构;β-半乳糖苷酶染色检测衰老相关半乳糖苷酶活性;免疫组织化学染色检测p21和p53蛋白表达水平;Ki67和PCNA免疫荧光染色检测细胞增殖活性;免疫荧光染色检测脾脏自噬蛋白分子Beclin1和APG5L/ATG5表达水平;活性氧荧光染色检测脾脏组织的活性氧含量;CD3免疫荧光染色检测总T淋巴细胞比例变化;酶联免疫吸附实验检测脾脏组织白细胞介素1β和转化生长因子β1分泌水平;DAPI复染细胞核观察绿色荧光蛋白标记的高活性脐带间充质干细胞在脾脏组织的分布情况。结果与结论:①高活性脐带间充质干细胞呈核小短梭形、鱼群样生长,G_(0)/G_(1)期占比大,具有向成脂、成骨和成软骨分化潜能。②感染复数为140且转染72 h为吉凯基因绿色荧光蛋白标记树鼩高活性脐带间充质干细胞的最佳条件。③与老年模型组相比,老年治疗组树鼩脾脏组织细胞排列紧密,白髓面积增加(P<0.01),红白髓界线清晰,生发中心占比无显著差异(P>0.05),脾脏组织衰老相关半乳糖苷酶活性水平降低(P<0.001),衰老蛋白分子p21和p53表达下调(P<0.001),增殖相关分子Ki67和PCNA表达上调(P<0.001,P<0.05),自噬相关分子Beclin1和APG5L/ATG5表达上调(P<0.001),活性氧含量降低(P<0.001),CD3^(+)T细胞比例增加(P<0.05),衰老相关分泌表型中白细胞介素1β分泌水平降低(P<0.001),转化生长因子β1分泌水平无显著差异(P>0.05)。与青年对照组相比,以上检测指标在老年治疗组中均有显著差异(P<0.05)。④冰冻组织切片观察可见老年治疗组树鼩脾脏组织中有绿色荧光蛋白标记的绿色荧光细胞。结果表明:静脉输注高活性脐带间充质干细胞可迁移至脾脏组织,抑制活性氧产生,下调衰老相关蛋白分子表达,诱导细胞自噬,促进细胞增殖,降低慢性炎症,进而改善脾脏组织结构和功能。

基于可持续理念的新型城市树木栽植技术——Silva Cell系统技术

城市树木被认为是绿色基础设施的重要组成部分,也是实现"城市森林"的主要手段和内容。Silva Cell系统作为美国新型城市树木栽植技术,主要解决城市硬质空间与树木生长之间的矛盾,实现城市树木的健康生长。文章在分析了城市树木价值和生长现状的基础上,就Silva Cell系统的构成、技术优势、设计原则和施工应用作了重点介绍。

Multiple cells of origin in cholangiocarcinoma underlie biological,epidemiological and clinical heterogeneity

Recent histological and molecular characterization of cholangiocarcinoma(CCA) highlights the heterogeneity of this cancer that may emerge at different sites of the biliary tree and with different macroscopic or morphological features.Furthermore,different stem cell niches have been recently described in the liver and biliarytree,suggesting this as the basis of the heterogeneity of intrahepatic(IH)-and extrahepatic(EH)-CCAs,which are two largely different tumors from both biological and epidemiological points of view.The complexity of the organization of the liver stem cell compartments could underlie the CCA clinical-pathological heterogeneity and the criticisms in classifying primitive liver tumors.These recent advances highlight a possible new classification of CCAs based on cells of origin and this responds to the need of generating homogenous diagnostic,prognostic and,hopefully,therapeutic categories of IH-and EH-CCAs.

Analysis of Syetem Reliability in Manufacturing Cell Based on Triangular Fuzzy Number

Due to lacking of test-data and field-data in reliability research during the design stage of manufacturing cell sys- tem.The degree of manufacturing cell system reliability research is increased.In order to deal with the deficient data and the un- certainty occurred from analysis and judgment,the paper discussed a method for studying reliability of manufacturing cell system through the analysis of fuzzy fault tree,which was based on triangular fuzzy number.At last,calculation case indicated that it would have great significance for ascertaining reliability index,maintenance and establishing keeping strategy towards manufac- turing cell system.

A Recursive Binary Tree Model for the Analysis of the Response to Antiretroviral Therapy of HIV Infected Adults in Burkina Faso

In this paper we aim to analyse temporal variation of CD4 cell counts for HIV-infected individuals under antiretroviral therapy by using statistical methods. This is achieved by resorting to recursive binary regression tree approach [1]?[2]. This approach has made it possible to highlight the existence of several segments of the population of interest described by the interactions between the predictive covariates of the response to the treatment regimen.

Vangenes Cell-Free DNA采血管与 Streck Cell-Free DNA采血管在无创产前检测应用中的效果比较

目的:比较Vangenes■Cell-Free DNA采血管和Streck■Cell-Free DNA 采血管对血液样品的运输保存效果.方法:通过静脉抽血, 18名志愿者分别使用Vangenes■Cell-Free DNA 采血管与Streck■Cell-Free DNA采血管各采集一管10mL血液.经过约50h运输样本回到实验室,进行血浆分离、游离DNA提取、构建文库、上机测序并进行建库浓度、测序数据的unique read counts、 GC%以及duplication值等分析.结果:经比较, Vangenes ?Cell-Free DNA采血管保存样品在血浆颜色、建库浓度以及测序数据的unique read counts、 GC%以及duplication值等达到了Streck■Cell-Free DNA 采血管保存样品相似的结果,二者不存在显著性差异.结论:在血液样品运输保存过程中, Vangenes■Cell-Free DNA采血管可有效阻止有核细胞破裂导致的基因组DNA对于游离DNA的污染,对于利用胎儿游离DNA进行的无创产前检测技术具有重要意义.

茶树油对脂多糖诱导奶牛小肠上皮细胞损伤的影响

本试验旨在研究茶树油(TTO)对脂多糖(LPS)诱导奶牛小肠上皮细胞(BIECs)损伤的影响。试验选取3头健康新生中国荷斯坦犊牛的空肠组织,分离并获得BIECs进行培养。通过使用不同浓度的LPS(0、1、2和4μg/mL)和不同浓度的TTO(0、0.00625%、0.01250%、0.02500%、0.05000%和0.10000%),建立细胞炎症模型。然后,对照组以不含TTO和LPS的培养基处理细胞;LPS组以1μg/mL的LPS处理细胞12 h;LPS+TTO组采用0.01250%和0.02500%的TTO预处理细胞12 h,经水洗后,再暴露于LPS处理12 h。结果表明:1)与对照组(未添加TTO)相比,添加0.00625%、0.01250%、0.02500%和0.05000%TTO对BIECs细胞活力无显著影响(P>0.05),添加TTO显著提高跨膜电阻(TEER)(P<0.05)。与对照组相比,添加0.01250%TTO显著提高BIECs中闭锁小带蛋白-1(ZO-1)、封闭蛋白(occludin)、闭合蛋白-1(claudin-1)和闭合蛋白-4(claudin-4)的mRNA相对表达量(P<0.05),显著降低肿瘤坏死因子-α(TNF-α)的mRNA相对表达量(P<0.05)。2)与LPS组相比,LPS+TTO组TEER以及ZO-1、occludin和claudin-1的mRNA相对表达量显著提高(P<0.05),TNF-α的mRNA相对表达量显著降低(P<0.05);LPS+TTO组ZO-1蛋白相对表达量显著提高(P<0.05)。综上可知,TTO可以通过上调紧密连接蛋白表达和下调炎性因子表达,缓解LPS诱导的犊牛小肠上皮细胞屏障功能障碍和炎症损伤。

Load Balancing for Hex-Cell Interconnection Network

The hex-cell is one of the interconnection networks used for parallel systems. The main idea of the hex-cell is that there are hexagon cells that construct the network;each one of those cells has six nodes. The performance of the network is affected by many factors one of the factors as load balancing. Until the moment of writing of this paper, there is no load balancing algorithm for this network. The proposed algorithm for dynamic load balancing on hex-cell is based on Tree Walking Algorithm (TWA) for load balancing on tree interconnection network and the ring all to all broadcast.

Secure Multicast Tree Construction Using Bacterial Foraging Optimization (BFO) for MANET

In Mobile Ad-Hoc Networks (MANET), the group communication for multiple senders and receivers threatens the security features. The multicasting is provoked to various security attacks, eavesdropping etc., hence secure multicasting requires imperative significance. The secure multicast tree construction using Bacterial Foraging Optimization (BPO) algorithm is proposed to develop a secure multicast tree construction in MANET. During routing, the proposed algorithm utilizes the public routing proxy to hide identity of the sender and receiver from other nodes for maintaining confidentiality. The public routing proxy is estimated using bacterial foraging optimization algorithm and path reliability is evaluated after the each iteration. Path reliability enhances the security of the network from black hole attacker and DoS attackers compared to traditional approaches for secure multicast tree formation in MANETs. By simulation results, we have shown that the proposed technique offers authentication and confidentiality during secure multicasting which is compared to conventional multicast tree formation algorithms in MANETs.

Molecular analysis and anticancer properties of two identified isolates,Fusarium solani and Emericella nidulans isolated from Wady El-Natron soil in Egypt against Caco-2(ATCC) cell line

Objective:To characterize,identify and investigate the anticancer properties of two new soil fungal isolates,Emericella nidulansand Fusarium solani isolated from Wady El-Natron in Egypt against colon cancer Caco-2(ATCCj cell line.Methods:Soil sample was cultured and two strains were chosen for morphological and phenotypical characterization.Partial sequences of the 18s rRNA gene and the internal transcribed spacer region ITS of the two isolates were amplified by PCR.Phylogenetic tree construction and analysis of the resulted multiple sequences from the two fugal isolates were also carried out.In vitro anticancer activity of the two strains was done against colon Caco-2 cancer cell line.Reverse transcription — PCR was carried out to detect level of expression of p53 in Caco-2 cell line.Results:HF.I displayed morphological and genotypic characteristics most similar to that of Fusarium solani while HF.2 was most similar to Emericella nidulans with high similarity of 99%and 97%respectively.The multiple sequence alignment of the two fungal isolates showed that,the maximum identical conserved domains in the 18s rRNA genes were identified with the nucleotide regions of Slst to 399th base pairs,88th to 525th base pairs respectively.While those in the ITS genes were identified with the nucleotide regions of 88th to 463rd and Slst to 274th.The two isolates showed IC<sub>50 value with（6.24±5.21） and（9.84±0.36） μ g/mL) concentrations respectively at 28h.Reverse transcription- PCR indicated that these cells showed high level of expression for p53 mRNA.Conclusions:The morphology and molecular analysis identified HF.1 and HF.2 to be Fusarium solani and Emericella nidulans;new isolates of anticancer producing fungi from Wady El-Natroon city in Egypt.Treatment with the two isolates caused P53 expression in Caco-2 cell line.These two isolates can be used as an anticancer agents.

Blocking optimized SIMD tree search on modern processors

Tree search is a widely used fundamental algorithm. Modern processors provide tremendous computing power by integrating multiple cores, each with a vector processing unit. This paper reviews some studies on exploiting single instruction multiple date （SIMD） capacity of processors to improve the performance of tree search, and proposes several improvement methods on reported SIMD tree search algorithms. Based on blocking tree structure, blocking for memory alignment and dynamic blocking prefetch are proposed to optimize the overhead of memory access. Furthermore, as a way of non-linear loop unrolling, the search branch unwinding shows that the number of branches can exceed the data width of SIMD instructions in the SIMD search algorithm. The experiments suggest that blocking optimized SIMD tree search algorithm can achieve 1.6 times response speed faster than the un-optimized algorithm.

树鼩角膜基质永生化细胞系的构建及其在病毒感染性方面的研究

目的建立树鼩永生化角膜基质细胞(corneal stromal cells,CSCs)系,并探讨其在病毒感染中的应用。方法利用组织块贴壁培养法分离培养树鼩原代CSCs,将携带SV40T基因的慢病毒转染细胞后,再挑取单克隆进行传代培养,传至50代以上进行形态学观察并与40代细胞形态进行比较,波形蛋白(vimentin)和SV40T基因免疫荧光鉴定、核型鉴定、细胞增殖曲线测定。用单纯疱疹病毒1型(herpes simplex virus-1,HSV-1)(McKrae株)、寨卡病毒(Zika virus,ZIKV)(GZ01株)、登革病毒Ⅱ型以及甲型流感病毒H1N1(PR8株)在该细胞上进行病毒感染实验。结果传至50代以上的树鼩永生化CSCs呈梭形,细胞形态结构与40代相比仍较好。vimentin和SV40T基因免疫荧光表达阳性。增殖曲线结果显示:细胞生长旺盛,第4~5天时处于对数生长期。原代细胞核型的染色体数稳定为62条,而永生化细胞第21、56代突变为64条且保持稳定。病毒感染实验显示:树鼩永生化CSCs对HSV-1(McKrae株)、ZIKV(GZ01株)、登革病毒Ⅱ型以及H1N1(PR8株)病毒敏感,产生较高感染滴度,分别为1.32×105、5.62×106、2.69×107、7.76×104CCID50/mL。结论成功建立了树鼩永生化CSCs细胞系,提示该细胞系可用于单纯疱疹病毒、寨卡病毒、登革病毒和甲型流感病毒感染眼角膜疾病的作用机制及抗病毒药物的研究。

Hormonally and chemically defined expansion conditions for organoids of biliary tree Stem Cells

Wholly defined ex vivo expansion conditions for biliary tree stem cell(BTSC)organoids were established,consisting of a defined proliferative medium(DPM)used in combination with soft hyaluronan hydrogels.The DPM consisted of commercially available Kubota's Medium(KM),to which a set of small molecules,particular paracrine signals,and heparan sulfate(HS)were added.The small molecules used were DNA methyltransferase inhibitor(RG108),TGF-βType I receptor inhibitor(A83-01),adenylate cyclase activator(Forskolin),and L-type Ca2+channel agonist(Bay K8644).A key paracrine signal proved to be R-spondin 1(RSPO1),a secreted protein that activates Wnts.Soluble hyaluronans,0.05%sodium hyaluronate,were used with DPM to expand monolayer cultures.Expansion of organoids was achieved by using DPM in combination with embedding organoids in Matrigel that was replaced with a defined thiol-hyaluronan triggered with PEGDA to form a hydrogel with a rheology[G*]of less than 100 Pa.The combination is called the BTSC-Expansion-Glycogel-System(BEX-gel system)for expanding BTSCs as a monolayer or as organoids.The BTSC organoids were expanded more than 3000-fold ex vivo in the BEX-gel system within 70 days while maintaining phenotypic traits indicative of stem/progenitors.Stem-cell-patch grafting of expanded BTSC organoids was performed on the livers of Fah-/-mice with tyrosinemia and resulted in the rescue of the mice and restoration of their normal liver functions.The BEX-gel system for BTSC organoid expansion provides a strategy to generate sufficient numbers of organoids for the therapeutic treatments of liver diseases.

Reconstructing cell lineage trees with genomic barcoding:approaches and applications

In multicellular organisms,developmental history of cell divisions and functional annotation of terminal cells can be organized into a cell lineage tree(CLT).The reconstruction of the CLT has long been a major goal in developmental biology and other related fields.Recent technological advancements,especially those in editable genomic barcodes and single-cell high-throughput sequencing,have sparked a new wave of experimental methods for reconstructing CLTs.Here we review the existing experimental approaches to the reconstruction of CLT,which are broadly categorized as either image-based or DNA barcode-based methods.In addition,we present a summary of the related literature based on the biological insight pro-vided by the obtained CLTs.Moreover,we discuss the challenges that will arise as more and better CLT data become available in the near future.Genomic barcoding-based CLT reconstructions and analyses,due to their wide applicability and high scalability,offer the potential for novel biological discoveries,especially those related to general and systemic properties of the developmental process.

CRISPR/Cas9系统介导的p53基因突变促进树鼩骨骼肌卫星细胞的增殖活性

目的:利用CRISPR/Cas9系统在树鼩骨骼肌卫星细胞中敲除p53基因并检测其增殖活性。方法:通过生物信息学方法对树鼩和15种哺乳动物的p53蛋白氨基酸序列进行同源性分析,根据树鼩基因组信息设计可编辑树鼩p53突变位点sgRNA,构建lenti CRISPR v2-sgp53基因编辑重组质粒,用293T细胞进行慢病毒包装,感染树鼩骨骼肌卫星细胞,嘌呤霉素筛选多克隆细胞并扩增;通过测序确定基因编辑效果。采用CCK8法检测细胞增殖活性,采用western blotting验证p53蛋白表达水平。结果:与人p53和小鼠p53氨基酸序列同源性(96.92%)相比,人p53和树鼩p53的氨基酸序列同源性(98.21%)更高。进化树分析显示,与小鼠相比,人与树鼩的亲缘关系更近。成功构建了3个靶向树鼩p53编辑的重组载体:lenti CRISPR v2-sgp53-g1、lenti CRISPR v2-sgp53-g2、lenti CRISPR v2-sgp53-g3,均成功在树鼩骨骼肌卫星细胞上实现p53基因编辑产生突变,导致p53功能丧失,p53的突变提高了树鼩骨骼肌卫星细胞的增殖能力。经药筛后的树鼩骨骼肌卫星细胞p53基因敲除成功,p53蛋白表达水平显著降低(P<0.01)。结论:本研究利用CRISPR/Cas9系统成功使树鼩骨骼肌卫星细胞p53基因突变、功能丧失,为后续树鼩p53基因敲除模型的建立提供了重要的分子生物学基础。

基于FTA-FBN的电动矿卡动力电池故障诊断

由于电动矿卡工作环境恶劣、载重量大、长期高负荷作业,其对动力电池可靠性造成严峻的考验。电动矿卡结构复杂,难以获取精确故障数据,故提出一种基于故障树和模糊贝叶斯网络(FBN)的动力电池故障诊断方法。利用电动矿卡实际故障数据,得到动力电池5类常见故障和8种故障现象,建立故障树模型,通过分析和计算获得各个故障事件的先验概率。通过专家评估的方法获得节点条件概率表,将模糊理论和贝叶斯网络相结合构建FBN,利用Netica仿真软件进行故障诊断推理。结果表明,能够根据故障树结果制定维修策略,根据FBN结果进行故障定位,提高效率。