与大肠癌相关的VEGF的研究进展

大肠癌是一种常见的恶性肿瘤,近年来随着饮食结构的变化,大肠癌的发病率呈上升趋势。研究与大肠癌相关的因子,对于大肠癌的防治是十分必要的。VEGF（血管内皮细胞生长因子）能诱导血管生成,和肿瘤的增殖、分化及转移密切相关。     

整合素β1、β3与肺癌转移的相关研究进展

整合素是一类粘附分子,表达于内皮细胞。随着肿瘤分子生物学研究的进展,对肿瘤分子机制的研究逐渐深入,发现整合素在肺癌转移各个步骤中起着重要作用。整合素与肺癌的转移相关性也逐渐成为研究热点。1整合素(integrin)的结构和功能概述整合素家族是一类由一个α亚单位和β亚单位通过非共价键连接而成的异二聚体跨膜粘蛋白。整合素每个亚单位均由长的细胞外区,短的胞浆区和穿膜区三部分构成(只有整合素β4有较长的胞内区)。目前已经确认的有18种α亚单位和8种β亚单位,共组成至少24种整合素[1]。而整合素β中以整合素β1和β3与肺癌转移关系…     

KAIl基因与恶性肿瘤浸润相关性的研究

浸润和转移是恶性肿瘤的重要特征 ,也是引起肿瘤病例死亡的主要原因。KAIl CD82属四次跨膜超家族的成员 ,其结构为细胞膜糖蛋白。目前研究多种肿瘤中均证实了转移的肿瘤往往伴随KAIl CD82基因的表达下降或缺失 ,最新研究发现TM 4SF家族部分成员可与整合素形成复合体 ,从而调节整合素的黏附功能 ,并影响整合素介导的细胞转移。     

大肠癌微血管和PCNA的形态计量学分析

肿瘤生长、侵袭及转移依赖新生血管生成，细胞增殖加快是癌细胞的基本特征，增殖细胞核抗原(PCNA)是一种细胞内与DNA转录、合成、修复有关的蛋白，常用于检测细胞的增殖活性。本研究采用免疫组化和病理图像分析技术对大肠癌微血管、PCNA进行检测以探讨其与临床病理因素的关系。     

KAIl基因与恶性肿瘤浸润相关性的研究

浸润和转移是恶性肿瘤的重要特征，也是引起肿瘤病例死亡的主要原因。KAIl／CD82属四次跨膜超家族的成员，其结构为细胞膜糖蛋白。目前研究多种肿瘤中均证实了转移的肿瘤往往伴随KAIl／CD82基因的表达下降或缺失，最新研究发现TM4SF家族部分成员可与整合素形成复合体，从而调节整合素的黏附功能，并影响整合素介导的细胞转移。     

整合素αvβ3与乳腺癌关系的研究进展

<正>乳腺癌是女性最常见的恶性肿瘤之一,发病率呈逐年上升趋势。据上海市疾病控制中心2011年统计数据显示,仅上海地区每年增加3%的乳腺癌患者。乳腺癌已占女性恶性肿瘤发病率的首位,成为威胁女性健康的疾病。近年来,随着肿瘤分子生物学的发展,人们已逐步发现细胞黏附分子中的整合素家族在肿瘤的生成、侵袭、转移以及肿瘤血管生成过程中发挥重要作用。该文就整合素αvβ3与乳腺癌之间的关系进行综述。     

细胞粘附分子与卵巢肿瘤

细胞粘附分子是一种参与细胞-细胞、细胞-细胞外基质间相互作用的跨膜粘蛋白，具有多种生理功能。近年研究发现，以广泛腹腔种值转移为特点的卵巢癌，其侵袭转移与细胞粘附分子密切相关，其中与整合素、钙粘附素、CD44关系更密切。鉴于国内CD44与卵巢肿瘤的关系已有报道，本文着重介绍整合素、钙粘附素与卵巢肿瘤的关系。     

血管生成素-2与大肠癌血管生成关系的研究

目的 探索大肠癌组织中血管生成素-2与大肠癌血管生成的关系.方法 采用免疫组化方法检测40例大肠癌组织及相应正常肠黏膜组织中血管生成素-2的表达,采用CD34标记计数肿瘤组织以及正常组织中微血管密度,分析血管生成素-2和大肠癌血管生成及临床病理因素关系.结果 大肠癌组织中Ang-2阳性表达率(62.5%,25/40)高于正常肠黏膜组织(12.5%,5/40),差异有统计学意义(P＜0.05).在大肠癌浸润浆膜中的阳性表达率高于未浸润浆膜,差异有统计学意义(P＜0.05),在大肠癌有淋巴结转移中高于无淋巴结转移,血管生成素-2和肿瘤的大小、年龄、性别无关.结论 血管生成素-2可能促进大肠癌的血管生成,进而促进大肠癌的发展和转移.     

细胞粘附分子与卵巢肿瘤

细胞粘附分子是一种参与细胞－细胞、细胞－细胞外基质间相互作用的跨膜粘蛋白，具有多种生理功能。近年研究发现，以广泛腹腔种植转移为特点的卵巢癌，其侵袭转移与细胞粘附分子密切相关，其中与整合素、钙粘附素、ＣＤ４４关系更密切。鉴别国内ＣＤ４４与卵巢肿瘤的关系已有报道，本文着重介绍整合素、钙粘附素与卵巢肿瘤的关系。     

转化生长因子β1、血管内皮细胞生长因子与大肠癌

大肠癌是一种常见消化道肿瘤 ,随着分子生物学的研究 ,对大肠癌的发生机理和癌变过程和大肠癌的发生、发展、浸润及预后有更进一步的研究。本文对大肠癌和血管生成中重要的促进因子转化生长因子 β1和血管内皮细胞生长因子的研究进展进行综述。1　血管生成的概念及其与肿瘤的关系肿瘤血管生成 (angiogenesis ,又称血管形成 )是指在肿瘤内生长的新形成的血管 ,包括从微血管前期到毛细血管生长形成新的血管结构。Folkman等[1～ 4 ] 认为肿瘤的生长和维持依赖于肿瘤的新生血管 ,当癌细胞繁殖到直径 1～ 2mm的球状团块时 ,摄取营养物质及排出废…     

颗粒细胞在卵母细胞发育成熟中的作用

卵泡的发育是涉及多种细胞、多个阶段的复杂过程,其中颗粒细胞和卵母细胞是构成卵泡的重要细胞,卵泡的形成需要颗粒细胞与卵母细胞间密切的相互作用。在促性腺激素等多种激素和信号分子作用下,颗粒细胞增殖、分化,并通过间隙连接与周围的颗粒细胞、卵母细胞、膜细胞进行物质交换和信号传递,卵母细胞也可分泌多种因子反作用于颗粒细胞。颗粒细胞与卵母细胞间的相互作用涉及多条信号通路,这些信号通路间同样存在相互影响,决定卵泡的成熟或闭锁。当这些信号通路被过度激活或抑制时,可影响细胞因子的生成或传递,从而引起颗粒细胞或卵泡的凋亡,具体机制尚未明确。本文就卵泡的形成,颗粒细胞与卵母细胞、膜细胞在发育过程中的相互作用以及涉及的重要信号通路进行综述。     

母胎界面免疫细胞的代谢调节与妊娠相关并发症的研究进展

维持妊娠需要母体免疫细胞与胎儿抗原之间的耐受平衡。母胎界面作为抵抗外来刺激的关键屏障,一直是探讨的热点。母胎界面除了胎盘和子宫之间相互作用,还受到构成蜕膜的母体免疫细胞的叠加调控。母胎免疫界面主要由自然杀伤细胞、巨噬细胞、T细胞和树突状细胞组成,这些细胞共同参与同种异体胎儿的耐受平衡及抗原防御作用。细胞代谢调节是细胞生物学功能的基础,为细胞不断提供着能量。妊娠过程中,为适应内外环境的变化母体代谢调节的速率及方向都随之变化。综述母胎界面免疫细胞的代谢调节,将母胎免疫界面的免疫学及代谢学联系起来,为免疫耐受提供新的见解,也为未来妊娠相关疾病的研究提供新的治疗方向。     

氧苯胂对人皮肤成纤维细胞缝隙连接通讯及DNA损伤的影响

分别采用细胞划痕染料标记示踪技术和单细胞凝胶电泳技术 ,研究了氧苯胂对人皮肤成纤维细胞缝隙连接通讯的影响及DNA的损伤作用。研究结果显示 ,氧苯胂可显著抑制细胞缝隙连接通讯 ,其作用有明显的剂量 -反应关系 (P <0 0 1) ,在浓度为 10 0nmol L时抑制作用最强 ;氧苯胂对细胞DNA的损伤作用不明显 ,损伤细胞以尾长小于头长的轻微型DNA断裂为主。以上研究结果提示 ,氧苯胂的遗传毒性较弱 ,而其非遗传毒性相对较强 ,有机砷化物的致癌作用不容忽视     

Effect of mucilage from yam on activation of lymphocytic immune cells

The immunostimulating activities of mucilage fraction from yam were investigated. The proliferation of BSA-primed lymph node cells was enhanced between 4.1- to 10.9-fold compare to control, when cultured with 1 to 25 µg/mL of yam-mucilage fraction. It showed strong immunopotentiating activity than ginseng extract and as remarkable as Bifidobacterium adolescentis M101-4 known as a positive immunostimulator. Mitogenicity to lymph node cells was fully induced by concanavalin A and lipopolysaccharide. The proliferation of splenocytes and Peyer''s patch cells was enhanced between 5.0- to 14.1-fold and 2.4- to 6.4-fold, respectively, when cultured with 1 to 25 µg/mL of yam-mucilage fraction. It enhanced the production of cytokines such as tumor necrosis factor-α and IL-6 in the culture of RAW 264.7 macrophage cells. In the culture of lipopolysaccharide-stimulated RAW 264.7 cells, production of cytokines was as similar as compared to controls. In unstimulated RAW 264.7 cells, both tumor necrosis factor-α and IL-6 production were enhanced between 15.6- to 60.1-fold and 2.3- to 9.1-fold, respectively. Mucilage fraction from yam is expected to be a safe immunopotentiator to maintain the host immunity and develop a physiologically functional food.     

Human natural killer cell function and their interactions with dendritic cells

Natural killer (NK) cells have long been considered as "primitive" and "non-specific" effector cells. However, the past 10 years have witnessed dramatic progress in our understanding of how NK cells function and their role in innate defenses. Thanks to specialized inhibitory receptors specific for MHC-class I molecules, they can sense the decrease or loss of these molecules, a typical condition of potentially dangerous cells such as tumor or virally-infected cells. NK cell triggering and lysis of these cells is mediated by several activating receptors and co-receptors that have recently been identified and cloned. While normal cells are usually resistant to the NK-mediated attack, a remarkable exception is represented by dendritic cells (DC). In their immature form (iDC), they are susceptible to NK-mediated lysis because of the expression of low levels of surface MHC-class I molecules. Since the process of DC maturation (mDC) is characterized by the surface expression of high levels of MHC-class I molecules, mDC become resistant to NK cells. Exposure to live bacteria induces rapid DC maturation and, thus, resistance to NK cells. The cross-talk between DC and NK cells is more complex and involves also a DC-dependent NK cell activation and proliferation. Thus, two important players of the innate immunity may be involved in a coordinated regulation of critical events occurring at the interface between innate and adaptive immunity.     

In utero cell transfer between porcine littermates

Trafficking of cells between mother and fetus during the course of normal pregnancy is well documented. Similarly, cells are known to travel between twins that share either a placenta (i.e. monozygotic) or associated chorion (i.e. monochorionic). Transferred cells are thought to be channelled via the vessels of the placenta or vascular connections established via the chorion and the long-term presence of these cells (i.e. microchimerism) can have important consequences for immune system function and reparative capacity of the host. Whether cells can be transferred between twins with separate placentas and separate chorions (i.e. no vascular connections between placentas) has not been investigated nor have the biological consequences of such a transfer. In the present study, we tested the possibility of this type of cell transfer by injecting human cord blood-derived cells into a portion of the littermates of swine and probing for human cells in the blood and tissues of unmanipulated littermates. Human cells were detected in the blood of 78% of unmanipulated littermates. Human cells were also detected in various tissues of the unmanipulated littermates, including kidney (56%), spleen (33%), thymus (11%) and heart (22%). Human cells were maintained in the blood until the piglets were sacrificed (8 months after birth), suggesting the establishment of long-term microchimerism. Our findings show that the transfer of cells between fetuses with separate placentas and separate chorions is significant and thus such twins may be subject to the same consequences of microchimerism as monozygotic or monochorionic counterparts.     

外泌体与生殖细胞生长发育的研究进展

卵母细胞和精子生长发育都受局部微环境中细胞因子的调控。在卵泡局部存在血-卵屏障,睾丸局部存在血-睾屏障,生殖细胞所在微环境是如何与机体进行信号转导和物质交换,这一过程尚不清楚。外泌体作为一种体液中普遍存在的膜性囊泡,可以参与细胞间的信号转导和物质交换,介导免疫耐受和促进肿瘤的发生发展等一系列的生理和病理活动,在卵泡或睾丸局部发挥重要的作用。卵巢来源的外泌体在卵泡的发生发展过程中具有一定的作用。在体外储存期间,精液中的外泌体对于维持精子的功能具有重要的作用。关于外泌体的研究是生殖医学中的一个新的领域,将会为生殖医学带来一个新的契机。     

Application of flow cytometry and PMA-qPCR to distinguish between membrane intact and membrane compromised bacteria cells in an aquatic milieu

The paper compares two methods of distinguishing between alive and dead cells by differentiation on the basis of their membrane structure: LIVE/DEAD flow cytometry and PMA-qPCR. LIVE/DEAD flow cytometry was established using the LIVE/DEAD^® BacLight™ Bacterial Viability Kit with different ratios of Legionella pneumophila and Escherichia coli cells with intact and compromised membranes (heat treated). The PMA-qPCR method was tested and modified, and results were compared with those from LIVE/DEAD flow cytometry using L. pneumophila cells.Ratios of membrane intact to membrane compromised cells were well shown by LIVE/DEAD flow cytometry in all combinations. PMA-qPCR seems to work best in even mixed ratios (1:1) of intact and compromised cells. In other respects, we noticed an overestimation of intact cells in the samples which contained a high percentage of membrane compromised cells, and an underestimation of intact cells in samples with a small percentage of membrane compromised cells. However, looking at total counts instead of ratios, the results were within an order of magnitude. This implies that the use of PMA-qPCR is appropriate only for a qualitative analysis to monitor the success of a process such as disinfection. Furthermore, we were able to assess that both methods have advantages and disadvantages: LIVE/DEAD flow cytometry as applied in this study works well on some bacteria monocultures, but does not distinguish between bacteria species. The PMA-qPCR method allows the possibility of distinguishing between membrane intact cells and membrane compromised cells and can be used to screen for specific bacteria.     

Mannose-resistant adhesion of motile Aeromonas to INT407 cells and the differences among isolates from humans, food and water.

Aeromonas has been recognized as an important enteropathogen, but factors related to its virulence have not been clarified. For most enteric pathogens, attachment is a prerequisite for infection and for the effective delivery of toxins to the intestinal epithelial cells. We examined a total of 273 strains isolated from stool, food and environmental specimens by an assay for mannose-resistant adhesion to INT407 cells in vitro. Seventeen of the 102 faecal isolates were adhesive strains with more than 10 bacteria adhering per cell, while only 2 of the 118 isolates from foods and river water adhered to the cells (P less than 0.001). It is possible that the adhesion might serve as a marker for discrimination between the pathogenic and nonpathogenic isolates. The 8 highly adhesive strains with more than 20 adhering organisms per cell were scrutinized for the mechanism of adhesion. No correlation was apparent between the adhesion to INT407 cells and hydrophobicity. It was noted that fucose inhibited the adhesion of four strains as well as haemagglutination by them. Electronmicroscopic studies showed the presence of flexible and curvilinear fimbriae in only 2 of the 8 highly adhesive strains.     

Roles of neural stem cells and adult neurogenesis in adolescent alcohol use disorders

This review discusses the contributions of a newly considered form of plasticity, the ongoing production of new neurons from neural stem cells, or adult neurogenesis, within the context of neuropathologies that occur with excessive alcohol intake in the adolescents. Neural stem cells and adult neurogenesis are now thought to contribute to the structural integrity of the hippocampus, a limbic system region involved in learning, memory, behavioral control, and mood. In adolescents with alcohol use disorders (AUDs), the hippocampus appears to be particularly vulnerable to the neurodegenerative effects of alcohol, but the role of neural stem cells and adult neurogenesis in alcoholic neuropathology has only recently been considered. This review encompasses a brief overview of neural stem cells and the processes involved in adult neurogenesis, how neural stem cells are affected by alcohol, and possible differences in the neurogenic niche between adults and adolescents. Specifically, what is known about developmental differences in adult neurogenesis between the adult and adolescent is gleaned from the literature, as well as how alcohol affects this process differently among the age groups. Finally, this review suggests differences that may exist in the neurogenic niche between adults and adolescents and how these differences may contribute to the susceptibility of the adolescent hippocampus to damage. However, many more studies are needed to discern whether these developmental differences contribute to the vulnerability of the adolescent to developing an AUD.