狗股动脉拉伸损伤后的顺应性变化

采用成年狗正常股动脉段６例，测定其拉伸后的压力一容积关系，并求出其顺应性。另取狗股狗股动脉段３０例拉伸固定后，观测其形态结构变化。发现狗股动脉段拉伸后的Ｐ－Ｖ曲线可用抛物线来拟合，狗股动脉段拉伸１５％后顺应性明显下降，其形态结构无明显改变，拉伸３０％后才出现明显的结构改变。狗股动脉拉伸后顺应性变化的出现较形态结构变化早。     

Activation of MAP kinases,pp90rsk and pp70-S6 kinases in mouse mast cells by signaling through the c-kit receptor tyrosine kinase or FcϵRI: rapamycin inhibits activation of pp70-S6 kinase and proliferation in mouse mast cells

The high-affinity receptor for IgE, Fc_?RI, represents the major cell surface structure through which mast cells express immunologically specific secretory function. By contrast, the stem cell factor receptor (SCFR), which is encoded by c-kit, is essential for normal mast cell development. The signaling pathways initiated by the stimulation of mast cells through the Fc_?RI, which lacks intrinsic kinase activity, and the SCFR, a member of the receptor tyrosine kinase family, generally have been regarded to be distinct. We report here that mouse mast cells stimulated either with SCF or with IgE and specific antigen exhibit a remarkably similar pattern of activation of mitogen-activated protein kinases (MAPK), 90 kDa-S6 kinases (pp90^rsk), and pp70-S6 kinases (pp70-S6K). These results indicate that all three families of protein kinases are associated with the cell surface receptor-dependent activation of secretion, as well as proliferation, in mast cells. We also show that the immunosuppressant rapamycin, but not FK506, can inhibit both SCF-dependent pp70-S6 kinase activation and SCF-dependent proliferation in mouse mast cells, without suppressing IgE- and antigen-dependent mediator release. These findings suggest that the activation of pp70-S6 kinase represents an important link in the stimulation of cell proliferation by SCF. Our results also indicate that the intracellular signaling pathways initiated by stimulation of mast cells through the Fc_?RI or the SCFR exhibit more overlap than has previously been appreciated.     

多脏器恶性肿瘤术后肝黏膜相关淋巴组织淋巴瘤

目的 探讨肝黏膜相关淋巴组织淋巴瘤的临床病理特征。方法 对1例罕见多脏器恶性肿瘤术后肝黏膜相关淋巴瘤病例结合文献进行临床、病理和免疫组化分析。结果 患者于8年和3年前先后发生胃恶性间质瘤、阴囊阴茎皮肤湿疹样癌，有长期化疗史。肿瘤组织学以单核样B细胞为主，并有淋巴滤泡和淋巴上皮病变形成。免疫表型示瘤细胞CD45、CD79α、CD20阳性，CD5、CD10、ALK、TdT阴性，bcl—2、Ki—67少数肿瘤细胞阳性。结论 肝黏膜相关淋巴瘤可以发生于多脏器恶性肿瘤术后，其发病可能与长期使用免疫抑制剂有关，诊断本病时需与肝继发性淋巴瘤及肝的炎性假瘤鉴别。     

Cholecystokinin antagonist and lipid intake as a function of caloric density and familiarity.

The effect of treatment with the cholecystokinin antagonist L364,718 on intake of different dilutions of corn oil emulsion was tested under two levels of familiarity with the oil emulsion. No increase in intake was observed. To see if the CCK antagonist was effective under our conditions, exogenous CCK was administered under the same conditions. A complete suppression of the large reduction produced by CCK on intake was found.     

衰老时海马神经元树突的可塑性增生

用形态计量的方法对老年(30个月)和成年(17个月)大鼠脑(Golgi染色标本)的海马CA3区锥体细胞的树突分支进行分级计数和测量了终末支的长度。结果是CA3神经元基树突和顶树突共有9级分支,衰老时第4级和第9级分支有显著的增多(P<0.02,P<0.03)。基树突终末支的长度衰老时无明显改变,顶树突终末支长度较成年组增加(P<0.05)。提示衰老时海马神经元的树突仍具有一定的增生和分化能力。这可能是对神经元退变的一种代偿机制。     

Differences between human and mouse alpha‐fetoprotein expression during early development

Alpha‐fetoprotein (AFP) is the major serum protein during development. AFP is one of the earliest proteins to be synthesised by the embryonic liver. The synthesis of AFP decreases dramatically after birth and only trace amounts are expressed in the adult liver. The tissue distribution of AFP in early human embryogenesis has not been defined. We have studied the expression pattern of AFP mRNA in human and mouse embryos by in situ hybridisation. In humans, AFP is expressed in the hepatic diverticulum at 26 d postovulation as it differentiates from the foregut endoderm (i.e. in the most primitive hepatocytes). It is also expressed in the endoderm of the gastrointestinal tract and in the yolk sac at this age. AFP is subsequently expressed in the mesonephros and transiently in the developing pancreas. In the mouse, no expression of AFP was observed in the mesonephros but other sites of expression were similar. Thus AFP has a distinct temporospatial expression pattern during the embryonic period and this differs between human and mouse species. It is interesting that AFP is expressed by tumours such as primitive gastrointestinal, renal cell and pancreatic tumours as well as those of hepatocyte origin. This distribution reflects the sites of AFP expression during development.     

Effect of anti-inflammatory medication on monocyte response to titanium particles

Cytokines produced by macrophages in the periprosthetic membranes surrounding joint replacements have been implicated as causal agents in osteolysis and prosthetic loosening. The present study characterizes the response of human peripheral blood monocytes to titanium particles. Monocytes were obtained from donated blood and were cultured in the presence of different-sized titanium particles. Exposure to titanium-aluminum-vanadium particles significantly changed the release of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and interleukin-1 (IL-1), whereas there was no significant effect on the release of prostaglandin E(2) (PGE(2)). When monocytes were cultured with particles, the titanium alloy particles induced significantly more release of TNF-alpha and less IL-1 secretion. Ciprofloxacin inhibited production of TNF-alpha, IL-6, IL-1, and PGE(2) in human monocytes exposed to titanium particles. In contrast to ciprofloxacin, indomethacin was not a potent inhibitor of TNF-alpha production but potentiated IL-6 production in titanium-stimulated monocytes. Indomethacin had no effect on the production of IL-1 and was a potent inhibitor of PGE(2) production in titanium-stimulated monocytes. Pentoxifylline had an inhibitor effect on TNF-alpha production in titanium-stimulated monocytes. Pentoxifylline potentiated IL-6 and IL-1 production in monocytes exposed to titanium particles and had a biphasic effect on the PGE(2) production. The results of this study support our hypothesis that human monocytes release bone resorption mediators after in vitro exposure to TiAlV alloy particles. The results also demonstrate the differences of bone-resorbing mediators in response to different wear particle size. The pharmacologic agents (ciprofloxacin, pentoxifylline, and indomethacin) that can modulate the release of bone resorbing mediators such as PGE(2), TNF-alpha, IL-1, and IL-6 release from human monocytes. The results help to elucidate the differences in cellular response to wear particles but may not be directly transposed to the human situation.     

MTEC 1分泌的趋化因子引起特定亚群胸腺细胞的定向迁移

分析胸腺髓质上皮样细胞系ＭＴＥＣ１分泌的化学趋化因子对胸腺细胞亚群的趋化作用。方法以抗体加补体杀伤结合免疫磁珠及ｐａｎｎｉｎｇ法，将小鼠胸腺细胞分离纯化，获得ＣＤ４＋ＣＤ８＋（ＤＰ），ＣＤ４－ＣＤ８－（ＤＮ），ＣＤ４＋ＣＤ８－（ＣＤ４ＳＰ）及ＣＤ４－ＣＤ８＋（ＣＤ８ＳＰ）四亚群细胞，用Ｂｏｙｄｅｎ小室分析ＭＴＥＣ１┐ＳＮ对四群胸腺细胞的趋化作用。结果ＭＴＥＣ１┐ＳＮ对ＤＰ及ＣＤ４ＳＰ胸腺细胞有趋化活性（ＣＩ＝６．６±１．０及６．１±１．８）；对ＣＤ８ＳＰ细胞有中度趋化活性（ＣＩ＝３．２±１．０）；对ＤＮ趋化活性微弱（ＣＩ＝１．３±０．６）。化学趋化因子ＭＣＰ┐１纯品对ＣＤ４ＳＰ胸腺细胞显示强趋化活性（ＣＩ＝５．６），对ＤＮ胸腺细胞则无可测出趋化活性。结论ＭＴＥＣ１分泌的化学趋化因子对ＤＰ，ＣＤ４ＳＰ及ＣＤ８ＳＰ胸腺细胞有显著趋化作用，对ＤＮ胸腺细胞几乎无趋化作用。提示此类化学趋化因子有趋使胸腺发育中后期阶段的细胞向胸腺髓质区迁移和定位的作用。