计算机辅助认知康复训练对脑卒中患者总体认知功能改善的Meta分析

目的:评价计算机辅助认知康复训练对脑卒中后认知损害患者总体认知功能的改善效果。方法:计算机检索Pubmed、EMbase、万方和CNKI数据库,搜集关于计算机辅助认知康复训练对脑卒中后认知损害患者总体认知功能改善效果的随机对照研究,时限为建库到2022年5月。文献的筛选、资料的提取和评价纳入研究的偏倚风险由2名研究者独立完成,最后采用RevMan5.3软件进行Meta分析。结果:共纳入9个RCT研究,包括467例患者。Meta分析结果显示,MMSE的效应值是1.97[0.52,3.42],MoCA的效应值是3.24[2.41,4.07]。在认知功能改善方面,计算机辅助认知康复训练效果优于人工认知康复训练。结论:4周及以上计算机辅助认知康复训练在改善脑卒中患者总体认知功能方面存在优势,临床上可根据不同患者、不同医院的具体情况制定康复方案,使认知功能得到有效的改善。受纳入研究数量和质量的限制,结论尚待更多高质量研究予以验证。

Lipid droplets in the nervous system:involvement in cell metabolic homeostasis

Lipid droplets serve as primary storage organelles for neutral lipids in neurons,glial cells,and other cells in the nervous system.Lipid droplet formation begins with the synthesis of neutral lipids in the endoplasmic reticulum.Previously,lipid droplets were recognized for their role in maintaining lipid metabolism and energy homeostasis;however,recent research has shown that lipid droplets are highly adaptive organelles with diverse functions in the nervous system.In addition to their role in regulating cell metabolism,lipid droplets play a protective role in various cellular stress responses.Furthermore,lipid droplets exhibit specific functions in neurons and glial cells.Dysregulation of lipid droplet formation leads to cellular dysfunction,metabolic abnormalities,and nervous system diseases.This review aims to provide an overview of the role of lipid droplets in the nervous system,covering topics such as biogenesis,cellular specificity,and functions.Additionally,it will explore the association between lipid droplets and neurodegenerative disorders.Understanding the involvement of lipid droplets in cell metabolic homeostasis related to the nervous system is crucial to determine the underlying causes and in exploring potential therapeutic approaches for these diseases.

Analysis on unit maximum capacity of orthogonal multiple watermarking for multimedia signals in B5G wireless communications

Beyond-5G(B5G)aims to meet the growing demands of mobile traffic and expand the communication space.Considering that intelligent applications to B5G wireless communications will involve security issues regarding user data and operational data,this paper analyzes the maximum capacity of the multi-watermarking method for multimedia signal hiding as a means of alleviating the information security problem of B5G.The multiwatermarking process employs spread transform dither modulation.During the watermarking procedure,Gram-Schmidt orthogonalization is used to obtain the multiple spreading vectors.Consequently,multiple watermarks can be simultaneously embedded into the same position of a multimedia signal.Moreover,the multiple watermarks can be extracted without affecting one another during the extraction process.We analyze the effect of the size of the spreading vector on the unit maximum capacity,and consequently derive the theoretical relationship between the size of the spreading vector and the unit maximum capacity.A number of experiments are conducted to determine the optimal parameter values for maximum robustness on the premise of high capacity and good imperceptibility.

Contrastive Consistency and Attentive Complementarity for Deep Multi-View Subspace Clustering

Deep multi-view subspace clustering (DMVSC) based on self-expression has attracted increasing attention dueto its outstanding performance and nonlinear application. However, most existing methods neglect that viewprivatemeaningless information or noise may interfere with the learning of self-expression, which may lead to thedegeneration of clustering performance. In this paper, we propose a novel framework of Contrastive Consistencyand Attentive Complementarity (CCAC) for DMVsSC. CCAC aligns all the self-expressions of multiple viewsand fuses them based on their discrimination, so that it can effectively explore consistent and complementaryinformation for achieving precise clustering. Specifically, the view-specific self-expression is learned by a selfexpressionlayer embedded into the auto-encoder network for each view. To guarantee consistency across views andreduce the effect of view-private information or noise, we align all the view-specific self-expressions by contrastivelearning. The aligned self-expressions are assigned adaptive weights by channel attention mechanism according totheir discrimination. Then they are fused by convolution kernel to obtain consensus self-expression withmaximumcomplementarity ofmultiple views. Extensive experimental results on four benchmark datasets and one large-scaledataset of the CCAC method outperformother state-of-the-artmethods, demonstrating its clustering effectiveness.

Editing of eIF(iso)4E.c confers resistance against Turnip mosaic virus in Brassica rapa

Turnip mosaic virus(TuMV)constitutes one of the primary diseases affecting Brassica rapa,severely impacting its production and resulting in crop failures in various regions worldwide.Recent research has demonstrated the significance of plant translation initiation factors,specifically the eIF4E and eIF4G family genes,as essential recessive disease resistance genes.In our study,we conducted evolutionary and gene expression studies,leading us to identify e IF(iso)4E.c as a potential TuMV-resistant gene.Leveraging CRISPR/Cas9 technology,we obtained mutant B.rapa plants with edited eIF(iso)4E.c gene.We confirmed eIF(iso)4E.c confers resistance against TuMV through phenotypic observations and virus content evaluations.Furthermore,we employed ribosome profiling assays on eif(iso)4e.c mutant seedlings to unravel the translation landscape in response to TuMV.Interestingly,we observed a moderate correlation between the fold changes in gene expression at the transcriptional and translational levels(R^(2)=0.729).Comparative analysis of ribosome profiling and RNA-seq data revealed that plant-pathogen interaction,and MAPK signaling pathway-plant pathways were involved in eIF(iso)4E.c-mediated TuMV resistance.Further analysis revealed that sequence features,coding sequence length,and normalized minimal free energy,influenced the translation efficiency of genes.Our study highlights that the loss of e IF(iso)4E.c can result in a highly intricate translation mechanism,acting synergistically with transcription to confer resistance against TuMV.

Summer Warming Limited Bud Output Drives a Decline in Daughter Shoot Biomass through Reduced Photosynthetis of Parent Shoots in Leymus chinensis Seedlings

Understanding how summer warming influences the parent and daughter shoot production in a perennial clonal grass is vital for comprehending the response of grassland productivity to global warming.Here,we conducted a simulated experiment using potted Leymus chinensis,to study the relationship between the photosynthetic activ-ity of parent shoots and the production of daughter shoots under a whole(90 days)summer warming scenario(+3°C).The results showed that the biomass of parents and buds decreased by 25.52%and 33.45%,respectively,under warming conditions.The reduction in parent shoot biomass due to warming directly resulted from decreased leaf area(18.03%),chlorophyll a(18.27%),chlorophyll b(29.21%)content,as well as a reduction in net photosynthetic rate(7.32%)and the maximum quantum efficiency of photosystem II(PSII)photochemistry(4.29%).The decline in daughter shoot biomass was linked to a decrease in daughter shoot number(33.33%)by warming.However,the number of belowground buds increased by 46.43%.The results indicated that long-term summer warming reduces biomass accumulation in parent shoot by increasing both limitation of stoma and non-stoma.Consequently,the parent shoot allocates relatively more biomass to the belowground organs to maintain the survival and growth of buds.Overall,buds,as a potential aboveground population,could remedy for the cur-rent loss of parent shoot density by increasing the number of future daughter shoots if summer warming subsides.

Simplified liver imaging reporting and data system for the diagnosis of hepatocellular carcinoma on gadoxetic acid-enhanced magnetic resonance imaging

BACKGROUND The liver imaging reporting and data system(LI-RADS)diagnostic table has 15 cells and is too complex.The diagnostic performance of LI-RADS for hepatocellular carcinoma(HCC)is not satisfactory on gadoxetic acid-enhanced magnetic resonance imaging(EOB-MRI).AIM To evaluate the ability of the simplified LI-RADS(sLI-RADS)to diagnose HCC on EOB-MRI.METHODS A total of 331 patients with 356 hepatic observations were retrospectively analysed.The diagnostic performance of sLI-RADS A-D using a single threshold was evaluated and compared with LI-RADS v2018 to determine the optimal sLIRADS.The algorithms of sLI-RADS A-D are as follows:The single threshold for sLI-RADS A and B was 10 mm,that is,classified observations≥10mm using an algorithm of 10-19 mm observations(sLI-RADS A)and≥20 mm observations(sLI-RADS B)in the diagnosis table of LI-RADS v2018,respectively,while the classification algorithm remained unchanged for observations<10 mm;the single threshold for sLI-RADS C and D was 20 mm,that is,for<20 mm observations,the algorithms for<10 mm observations(sLI-RADS C)and 10-19 mm observations(sLI-RADS D)were used,respectively,while the algorithm remained unchanged for observations≥20 mm.With hepatobiliary phase(HBP)hypointensity as a major feature(MF),the final sLI-RADS(F-sLI-RADS)was formed according to the optimal sLI-RADS,and its diagnostic performance was evaluated.The times needed to classify the observations according to F-sLIRADS and LI-RADS v2018 were compared.RESULTS The optimal sLI-RADS was sLI-RADS D(with a single threshold of 20 mm),because its sensitivity was greater than that of LI-RADS v2018(89.8%vs 87.0%,P=0.031),and its specificity was not lower(89.4%vs 90.1%,P>0.999).With HBP hypointensity as an MF,the sensitivity of F-sLI-RADS was greater than that of LI-RADS v2018(93.0%vs 87.0%,P<0.001)and sLI-RADS D(93.0%vs 89.8%,P=0.016),without a lower specificity(86.5%vs 90.1%,P=0.062;86.5%vs 89.4%,P=0.125).Compared with that of LI-RADS v2018,the time to classify lesions according to FsLI-RADS was shorter(51±21 s vs 73±24 s,P<0.001).CONCLUSION The use of sLI-RADS with HBP hypointensity as an MF may improve the sensitivity of HCC diagnosis and reduce lesion classification time.

我国铁路标准国际化面临挑战及应对策略研究

随着全球经济一体化的推进和中国“一带一路”倡议的深入实施,我国企业承担海外铁路工程项目日益增多,但我国铁路工程建设标准应用推进过程中仍存在标准认同性不高、兼容互通性不足和标准国际化人才缺乏等问题。本文聚焦我国铁路标准在海外建设项目中的实际应用情况及面临的困难,结合典型应用案例,为推动我国铁路标准国际化提出建议。

B原子掺杂调控CuIn纳米合金电子结构以实现电化学CO_(2)还原宽电位活性

杂原子掺杂可以调节电子结构以调整中间体吸附并优化反应路径,是设计高效CO_(2)还原反应(CO_(2)RR)催化剂的有应用前景的方法.B原子是常用的掺杂剂,引入B原子可以有效打破*COOH和OCHO*中间体的吉布斯自由能线性关系,并且可以通过与CO_(2)中O原子结合来增强CO_(2)吸附能力.B掺杂碳材料、单金属和金属氧化物的研究结果表明,B原子掺杂催化剂的CO_(2)RR活性和/或选择性有明显提高,然而多数报道的单个活性位点的B掺杂催化剂仅表现出在相对狭窄的电位范围内的CO_(2)RR高性能,设计制备CO_(2)RR的宽电位高选择性催化剂仍是巨大挑战.研究表明,合金化是提供多种类的活性位点相互协调和增强催化剂固有活性,进而改善CO_(2)RR性能并调节产物分布的可行策略.引入B原子到合金中以调节电子结构,最终优化关键中间体吸附的活性位点,对于寻找具有宽电位窗口的先进催化剂具有重要意义.本文提出了一种通过B掺杂调节CuIn合金电子结构以实现宽电位高选择性的电子工程策略.所制得的B掺杂CuIn合金(CuIn(B))在–0.6 V(vs.RHE)时表现出99%的CO法拉第效率(FECO),并在一个宽的阴极电化学窗口(400 m V)内保持了超过90%的较高FECO.同时,采用X射线光电子能谱(XPS)和CO_(2)吸附实验等手段研究了CuIn(B)性能提升的原因,结果表明,B原子与CuIn之间存在强烈的相互作用,改变了CuIn的电子结构.CO_(2)吸附结果表明,CuIn(B)比CuIn拥有更强的CO_(2)吸附能力,证明它具有潜在的快速CO_(2)RR反应动力学.进一步通过密度泛函理论(DFT)模拟研究了催化剂的热力学反应能量学以揭示CO_(2)RR机制,结果表明,*COOH更倾向于在CuIn(B)上形成,且*CO与CuIn(B)催化位点的结合强度最佳,更利于CO_(2)还原反应为CO,而CuIn更利于作为HER的活性位点;决速步骤是*CO中间体向CO转移,以实现高CO选择性;热力学限制电位研究表明,CuIn(B)大大提高了CO_(2)到CO转化的选择性.随后通过差分电荷密度研究也进一步证明了电荷转移过程是从CuIn位点到B位点.此外,根据d带理论,催化剂中Cu和In原子的投影态密度和d带中心(Ed)研究进一步证明了催化剂结构中的电子价态的变化,与XPS结果相符;引入B可以优化催化剂的电子结构,从而调节催化剂和中间体之间的结合能力,实现了CO_(2)RR在宽电位范围内的高活性和选择性.综上,本文对于电化学CO_(2)RR机理的基础理解和其实际应用具有促进作用.

Smart heat isolator with hollow multishelled structures

Safe, green and efficient industrial production has always been the pursuit of the chemical industry. Since thermal energy is the driving force for most of chemical reactions, an ideal reaction tank would have the capacity to automatically regulate heat conduction rate. In detail, this reaction tank should endow an ability that resists the heat loss when the reaction temperature is lower than the target, while accelerating the heat dissipation when the system is overheated. In this case, this smart reactor can not only minimize energy consumption but also reduce safety risks.Hollow structures are known to reduce heat conductivity. Particularly, the hollow structure with multishells can provide more interfaces and thus further inhibit heat transmission, which would be more favorable for heat isolation. Step forward, by coupling HoMSs with temperature-sensitive polymer, a smart heat isolation material has been fabricated in this work. It performs as a good heat isolator at a relatively lower temperature. A heat insulation effect of 6.5℃ can be achieved for the TSPU/3S–TiO_(2)HoMSs with a thickness of 1 mm under the temperature field of 50℃.The thermal conductivity of composite material would be raised under overheating conditions. Furthermore, this composite displays an unusual two-stage phase transformation during heating. Benefiting from the unique multishelled structure, energy is found to be gradually guided into the hollow structure and stored inside. This localized heat accumulation enables the composite to be a potential coating material for intelligent thermal-regulator and site-defined micro-reactor.

Transcriptomic and genetic approaches reveal that low-light-induced disease susceptibility is related to cellular oxidative stress in tomato

The impact of low light intensities on plant disease outbreaks represents a major challenge for global crop security,as it frequently results in significant yield losses.However,the underlying mechanisms of the effect of low light on plant defense are still poorly understood.Here,using an RNA-seq approach,we found that the susceptibility of tomato to Pseudomonas syringae pv.tomato DC3000(Pst DC3000)under low light was associated with the oxidation-reduction process.Low light conditions exacerbated Pst DC3000-induced reactive oxygen species(ROS)accumulation and protein oxidation.Analysis of gene expression and enzyme activity of ascorbate peroxidase 2(APX2)and other antioxidant enzymes revealed that these defense responses were significantly induced by Pst DC3000 inoculation under normal light,whereas these genes and their associated enzyme activities were not responsive to pathogen inocula-tion under low light.Additionally,the reduced ascorbate to dehydroascorbate(AsA/DHA)ratio was lower under low light compared with normal light conditions upon Pst DC3000 inoculation.Furthermore,the apx2 mutants generated by a CRISPR-Cas9 gene-editing approach were more susceptible to Pst DC3000 under low light conditions.Notably,this increased susceptibility could be significantly reduced by exogenous AsA treatment.Collectively,our findings suggest that low-light-induced disease susceptibility is associated with increased cellular oxidative stress in tomato plants.This study sheds light on the intricate relationship between light conditions,oxidative stress,and plant defense responses,and may pave the way for improved crop protection strategies in low light environments.

Can the Educational Metaverse Enter the Real Classroom?-From the Perspective of Frontline Teachers

This article dissects the challenges faced and the integration strategies for embracing the educational metaverse from existing research,preparing for the new educational trend-the educational metaverse-by controlling the target direction,technical direction,teacher training direction,and ethical direction.Starting from the origin,it analyzes the reasons for the entry of the metaverse into the educational field and summarizes the three characteristics of the educational metaverse supported by current technical means.Combining the current situation of classroom teaching and the advantages of the educational metaverse,it analyzes the inevitability of the metaverse entering the classroom.Subsequently,it analyzes the four major challenges of the current stage:the pressure of college entrance examinations,the challenge of technical implementation,the limited ability of teachers,and the digital ethical risks brought by the metaverse.It prescribes the right remedy,giving strategies for integrating the educational metaverse into the classroom from the four directions of reducing the burden of college entrance examinations,technology research,teacher ability development,and rule formulation.It is hoped that in the future,while the metaverse lands in the educational field,it can overcome challenges at various levels and achieve breakthroughs at the target level,technical level,teacher training level,and ethical level to truly realize the entry of the educational metaverse into the classroom.

选择性动脉介入术治疗妊娠滋养细胞肿瘤临床分析

目的:探讨选择性动脉栓塞(selective arterial embolization,SAE)术和动脉灌注化疗栓塞术在妊娠滋养细胞肿瘤(gestational trophoblastic neoplasia,GTN)治疗中的应用价值。方法:回顾性分析2010年7月至2020年1月27例于首都医科大学附属北京妇产医院行SAE治疗的GTN患者临床资料,分为动脉灌注化疗栓塞组(n=14)和单纯动脉栓塞组(n=13),所有患者行SAE治疗联合静脉化疗。超声检查子宫病灶大小改变、检测血清人绒毛膜促性腺激素(β-human chorionic gonadotropin,β-HCG)下降水平及保留生育功能情况。结果:患者平均年龄为35.37(19~51)岁,17例活动性出血患者行SAE治疗后出血均得到有效控制,患者行静脉化疗的总疗程中位数为4个疗程,治疗过程中行子宫切除为6例。两组患者行SAE联合静脉化疗1个疗程,超声检查评定治疗有效率为51.8%(14/27),两组间比较差异无统计学意义(P=0.413);血清β-HCG平均下降(2.07±0.91)个对数,两组间比较差异无统计学意义(P=0.987)。结论:SAE治疗用于预防或控制高危GTN病灶出血效果肯定,动脉灌注化疗未明显提高动脉栓塞联合静脉化疗的疗效。

电子结肠镜检查在儿童下消化道出血中的应用价值

目的探讨电子结肠镜检查在儿童下消化道出血(LGIB)中的临床应用价值和胃镜替代电子结肠镜检查的可行性。方法回顾性分析2017年1月-2020年3月该院消化内科收治的267例LGIB患儿的病历资料,对病因及电子结肠镜检查结果进行归纳总结。结果学龄前儿童占69.29%。儿童LGIB的常见病因为肠道息肉、结直肠炎、炎症性肠病(IBD)、过敏性结肠炎、过敏性紫癜(HSP)和梅克尔憩室。其中,肠道息肉、IBD、嗜酸细胞性胃肠炎、过敏性结肠炎和白塞病的诊断阳性率达100.00%。通过内镜直视下局部止血治疗29例,镜下高频电凝电切治疗肠道息肉100例,均安全有效。267例患儿行电子结肠镜检查268例次,完成全结肠检查234例,总体盲肠插管率为87.31%。其中,电子结肠镜检查227例(盲肠插镜率为90.31%),胃镜代电子结肠镜检查41例(盲肠插镜率为70.73%)。结论电子结肠镜检查在儿童LGIB诊疗中安全有效,不同病因导致的LGIB在电子结肠镜下表现不同,对于1岁以下或体重小于10 kg的患儿,采用胃镜替代电子结肠镜检查安全可行。

槐耳清膏对免疫性血小板减少症患者B淋巴细胞的作用研究

目的:探究槐耳清膏对免疫性血小板减少症(immune thrombocytopenic purpura,ITP)患者B淋巴细胞及其亚群的作用。方法:分析2019年1月至2020年3月大连医科大学附属第二医院诊断的20例ITP患者的外周血,患者中位年龄53.5(16.0~87.0)岁,其中男性8例,女性12例。首先采用流式细胞术比较患者与健康对照者CD19^(+)B淋巴细胞及其亚群CD19^(+)CD27^(+)记忆B淋巴细胞、CD19^(+)CD24^(+)CD38^(+)调节B淋巴细胞比例异同;用不同浓度(2、4、6 mg·mL^(-1))槐耳清膏处理B淋巴细胞株,应用CCK-8检测槐耳清膏对B淋巴细胞增殖的影响;流式细胞仪测定槐耳清膏处理外周血72 h后B淋巴细胞亚群的变化。结果:ITP患者CD19^(+)B淋巴细胞比例明显高于正常对照;中药槐耳清膏能够抑制B淋巴细胞的增殖,抑制ITP患者记忆性B淋巴细胞及调节B淋巴细胞。结论:中药槐耳清膏能抑制ITP患者B淋巴细胞的增殖,本研究为临床的应用提供理论依据。

酸洗海藻酸盐碳气凝胶的制备及染料吸附特性研究

本研究以海藻酸钠为原材料经过湿法纺丝、交联、碳化、酸洗四步制备碳气凝胶材料,该碳气凝胶对阳离子染料亚甲基蓝、阴离子染料甲基橙展现出良好的吸附性能。研究了吸附剂投加量、吸附时间和初始浓度对染料吸附效果的影响。实验结果表明:随着碳气凝胶投加量的增加,溶液中两种染料的去除率增加,吸附量减小;碳气凝胶对两种染料的吸附过程符合准二级动力学模型(R2 >0.999)以及Langmuir等温吸附模型,说明碳气凝胶对两种染料的吸附主要是化学吸附和单分子层吸附。碳气凝胶对亚甲基蓝、甲基橙的吸附量分别为196.38 mg/g、187.44 mg/g。

Spatial-temporal coupling between high-quality source rocks and reservoirs for tight sandstone oil and gas accumulations in the Songliao Basin, China

The spatial-temporal relationship between high-quality source rocks and reservoirs is a key factor when evaluating the formation,occurrence,and prospectivity of tight oil and gas reservoirs.In this study,we analyze the fundamental oil and gas accumulation processes occurring in the Songliao Basin,contrasting tight oil sand reservoirs in the south with tight gas sand reservoirs in the north.This is done using geochemical data,constant-rate and conventional mercury injection experiments,and fluid inclusion analyses.Our results demonstrate that as far as fluid mobility is concerned,the expulsion center coincides with the overpressure zone,and its boundary limits the occurrence of tight oil and gas accumulations.In addition,the lower permeability limit of high-quality reservoirs,controlled by pore-throat structures,is 0.1×10^-3μm^2 in the fourth member of the Lower Cretaceous Quantou Formation(K1q^4)in the southern Songliao Basin,and 0.05×10^-3μm^2 in the Lower Cretaceous Shahezi Formation(K1sh)in the northern Songliao Basin.Furthermore,the results indicate that the formation of tight oil and gas reservoirs requires the densification of reservoirs prior to the main phase of hydrocarbon expulsion from the source rocks.Reservoir“sweet spots”develop at the intersection of high-quality source rocks(with high pore pressure)and reservoirs(with high permeability).

Transcriptomic and genetic approaches reveal an essential role of the NAC transcription factor SlNAP1 in the growth and defense response of tomato

With global climate change,plants are frequently being exposed to various stresses,such as pathogen attack,drought,and extreme temperatures.Transcription factors(TFs)play crucial roles in numerous plant biological processes;however,the functions of many tomato(Solanum lycopersicum L.)TFs that regulate plant responses to multiple stresses are largely unknown.Here,using an RNA-seq approach,we identified SlNAP1,a NAC TF-encoding gene,which was strongly induced by various stresses.By generating SlNAP1 transgenic lines and evaluating their responses to biotic and abiotic stresses in tomato,we found that SlNAP1-overexpressing plants showed significantly enhanced defense against two widespread bacterial diseases,leaf speck disease,caused by Pseudomonas syringae pv.tomato(Pst)DC3000,and root-borne bacterial wilt disease,caused by Ralstonia solanacearum.In addition,SlNAP1 overexpression dramatically improved drought tolerance in tomato.Although the SlNAP1-overexpressing plants were shorter than the wild-type plants during the early vegetative stage,eventually,their fruit yield increased by 10.7%.Analysis of different hormone contents revealed a reduced level of physiologically active gibberellins(GAs)and an increased level of salicylic acid(SA)and abscisic acid(ABA)in the SlNAP1-overexpressing plants.Moreover,EMSAs and ChIP-qPCR assays showed that SlNAP1 directly activated the transcription of multiple genes involved in GA deactivation and both SA and ABA biosynthesis.Our findings reveal that SlNAP1 is a positive regulator of the tomato defense response against multiple stresses and thus may be a potential breeding target for improving crop yield and stress resistance.

Green tea compounds in breast cancer prevention and treatment

Breast cancer is the most common cancer among women. In recent years, many in vitro and in vivo studies indicate that green tea possesses anti-cancer effects. The epidemiological studies, however, have produced inconclusive results in humans. Likewise, results from animal models about the preventive or therapeutic effects of green tea components are inconclusive. The mechanisms by which green tea intake may influence the risk of breast cancer in humans remain elusive. Here, we review recent studies of green tea polyphenols and their applications in the prevention and treatment of breast cancer. Furthermore, we discuss the effect of green tea components on breast cancer by reviewing epidemiological studies, animal model studies and clinical trials. At last, we discuss the mechanisms by which green tea components suppress the develop-ment and recurrence of breast cancer. A better understanding of the mechanisms will improve the utilization of green tea in breast cancer prevention and therapy and pave the way to novel prevention and treatment strategies for breast cancer.

Differentiation of mesenchymal stem cells into neuronal cells on fetal bovine acellular dermal matrix as a tissue engineered nerve scaffold

The purpose of this study was to assess fetal bovine acellular dermal matrix as a scaffold for supporting the differentiation of bone marrow mesenchymal stem cells into neural cells fol-lowing induction with neural differentiation medium. We performed long-term, continuous observation of cell morphology, growth, differentiation, and neuronal development using several microscopy techniques in conjunction with immunohistochemistry. We examined speciifc neu-ronal proteins and Nissl bodies involved in the differentiation process in order to determine the neuronal differentiation of bone marrow mesenchymal stem cells. The results show that bone marrow mesenchymal stem cells that differentiate on fetal bovine acellular dermal matrix display neuronal morphology with unipolar and bi/multipolar neurite elongations that express neuro-nal-speciifc proteins, includingβIII tubulin. The bone marrow mesenchymal stem cells grown on fetal bovine acellular dermal matrix and induced for long periods of time with neural differen-tiation medium differentiated into a multilayered neural network-like structure with long nerve ifbers that was composed of several parallel microifbers and neuronal cells, forming a complete neural circuit with dendrite-dendrite to axon-dendrite to dendrite-axon synapses. In addition, growth cones with filopodia were observed using scanning electron microscopy. Paraffin sec-tioning showed differentiated bone marrow mesenchymal stem cells with the typical features of neuronal phenotype, such as a large, round nucleus and a cytoplasm full of Nissl bodies. The data suggest that the biological scaffold fetal bovine acellular dermal matrix is capable of supporting human bone marrow mesenchymal stem cell differentiation into functional neurons and the subsequent formation of tissue engineered nerve.