MicroRNA let - 7f 对胃癌细胞株 SGC7901 / ADR 耐药性的影响

目的：通过检测胃癌细胞株SGC7901及其阿霉素耐药细胞株SGC7901/ADR中microRNA let-7f的表达差异,探讨let-7f表达与胃癌细胞对ADR耐药的关系.方法：通过实时荧光定量PCR比较SGC7901/ADR与SGC7901两种细胞中 let-7f表达水平的差异;MTT法检测SGC7901,SGC7901/ADR及转染let-7f mimic后SGC7901/ADR的药物敏感性;流式细胞仪检测细胞凋亡;Western Blot检测凋亡相关分子Bcl-2和Caspase-3蛋白表达情况.结果：qRT-PCR结果显示,let-7f在SGC7901/ADR细胞中的表达较在SGC7901中的表达显著降低（ P＜0.05）.MTT法结果显示SGC7901与SGC7901/ADR两种细胞阿霉素的半数抑制浓度（IC50）分别为（0.95 ±0.08）g/L和（5.40 ±0.28）g/L.SGC7901/ADR细胞转染let-7f mimic后,let-7f表达显著上调,并且对阿霉素的IC50明显降低（ P＜0.05）.凋亡检测结果显示,转染let-7f mimic后,SGC7901/ADR细胞凋亡率明显增加（ P＜0.05）.Western Blot结果表明相较于转染let-7f negative control（NC）组,转染let-7f mimic组cleaved-Caspase-3表达显著降低（P＜0.05）,而两组中的Bcl-2表达水平无差异.结论：let-7f在胃癌阿霉素耐药细胞株SGC7901/ADR中的表达显著降低,逆转let-7f表达可增加其对阿霉素敏感性,并诱导其凋亡.     

Metformin reduces morphine tolerance by inhibiting microglial-mediated neuroinflammation

Background

Tolerance seriously impedes the application of morphine in clinical medicine. Thus, it is necessary to investigate the exact mechanisms and efficient treatment. Microglial activation and neuroinflammation in the spinal cord are thought to play pivotal roles on the genesis and maintaining of morphine tolerance. Activation of adenosine monophosphate-activated kinase (AMPK) has been associated with the inhibition of inflammatory nociception. Metformin, a biguanide class of antidiabetic drugs and activator of AMPK, has a potential anti-inflammatory effect. The present study evaluated the effects and potential mechanisms of metformin in inhibiting microglial activation and alleviating the antinociceptive tolerance of morphine.

Methods

The microglial cell line BV-2 cells and mouse brain-derived endothelial cell line bEnd3 cells were used. Cytokine expression was measured using quantitative polymerase chain reaction. Cell signaling was assayed by western blot and immunohistochemistry. The antinociception and morphine tolerance were assessed in CD-1 mice using tail-flick tests.

Results

We found that morphine-activated BV-2 cells, including the upregulation of p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation, pro-inflammatory cytokines, and Toll-like receptor-4 (TLR-4) mRNA expression, which was inhibited by metformin. Metformin suppressed morphine-induced BV-2 cells activation through increasing AMPK phosphorylation, which was reversed by the AMPK inhibitor compound C. Additionally, in BV-2 cells, morphine did not affect the cell viability and the mRNA expression of anti-inflammatory cytokines. In bEnd3 cells, morphine did not affect the mRNA expression of interleukin-1β (IL-1β), but increased IL-6 and tumor necrosis factor-α (TNF-α) mRNA expression; the effect was inhibited by metformin. Morphine also did not affect the mRNA expression of TLR-4 and chemokine ligand 2 (CCL2). Furthermore, systemic administration of metformin significantly blocked morphine-induced microglial activation in the spinal cord and then attenuated the development of chronic morphine tolerance in mice.

Conclusions

Metformin significantly attenuated morphine antinociceptive tolerance by suppressing morphine-induced microglial activation through increasing AMPK phosphorylation.

     

Interleukin-1β transfer across the blood–brain barrier in the ovine fetus

Pro-inflammatory cytokines contribute to hypoxic–ischemic brain injury. Blood–brain barrier (BBB) dysfunction represents an important component of hypoxic–ischemic brain injury in the fetus. Hypoxic–ischemic injury could accentuate systemic cytokine transfer across the fetal BBB. There has been considerable conjecture suggesting that systemic cytokines could cross the BBB during the perinatal period. Nonetheless, evidence to support this contention is sparse. We hypothesized that ischemia–reperfusion increases the transfer of systemic interleukin-1β (IL-1β) across the BBB in the fetus. Ovine fetuses at 127 days of gestation were studied 4 hours after 30 minutes of bilateral carotid artery occlusion and compared with a nonischemic group. Recombinant ovine IL-1β protein was expressed from an IL-1β pGEX-2 T vector in E. coli BL-21 cells and purified. The BBB function was quantified in 12 brain regions using a blood-to-brain transfer constant with intravenous ¹²⁵I-radiolabeled IL-1β (¹²⁵I-IL-1β). Interleukin-1β crossed the intact BBB in nonischemic fetuses. Blood-to-brain transport of ¹²⁵I-IL-1β was higher (P<0.05) across brain regions in fetuses exposed to ischemia–reperfusion than nonischemic fetuses. We conclude that systemic IL-1β crosses the intact fetal BBB, and that ischemia–reperfusion increases transfer of this cytokine across the fetal BBB. Therefore, altered BBB function after hypoxia–ischemia facilitates entry of systemic cytokines into the brain of the fetus.     

根据孕妇参数预测胎儿体重的神经网络方法

本文采用反向传播神经网络算法,根据孕妇身高、体重、宫高及腹围预测胎儿体重。建立了一个预测胎儿体重的网络模型,讨论了确定网络拓扑结构的方法。采用该方法预测了１４０例胎儿体重,预测符合率高达８５％,相对误≤１０％者占预测总数的９４．２８％。采用神经网络分析输入对于输出的贡献的结果表明孕妇宫高对于胎儿体重影响最大。     

大承气汤加减治疗脑病医案3则

通过病案举例,介绍大承气汤在中医脑病治疗中的使用技巧,说明大承气汤可以运用于出血性中风头痛、癫痫、失眠等多种脑病的治疗,疗效显著。大承气汤具有通腑泄热、祛邪外出的作用。对于六经辨证属阳明腑实证者,无论病种,皆可用大承气汤加味化裁。     

邻指指动脉逆行岛状皮瓣修复手指中节皮肤及软组织缺损

目的：探讨邻指指动脉逆行岛状皮瓣在修复手指中节皮肤及软组织缺损中的应用价值。方法：1998年3月至2001年12月，利用邻指根部指动脉逆行岛状皮瓣修复26例手指中节皮肤及软组织缺损，示指6例，中指16例，环指4例，结果：26例皮瓣均全部成活，术后随访3－10个月，皮瓣外观，质地满意，感觉恢复至S3－3 ，供皮区外观较好，功能无明显影响，结论：邻指根部指动脉逆行岛状皮瓣是修复中节手指皮肤及软组织缺损的好方法。     

肾疏宁对大鼠系膜增生性肾炎的肾小管间质损害的形态学影响

目的 :观察中药肾疏宁对系膜增生性肾炎 (MsPGN )的肾小管间质损伤的影响。方法 :制作大鼠MsPGN模型。予肾疏宁治疗并以肾炎康复片为对照组 ,观察肾脏形态学及 2 4h尿蛋白定量。结果 :肾疏宁能明显减轻MsPGN大鼠的蛋白尿 ,减轻肾组织病理病变尤其是肾小管间质损伤 ,且对损伤的肾组织有修复作用。与模型组相比 ,有显著性差异 (P <0 .0 1) ,与肾炎康复片组相比 ,有显著性差异 (P <0 .0 5 ) ;与正常组相比 ,无显著性差异 (P >0 .0 5 )。结论 :肾疏宁能降低尿蛋白、保护肾功能、减轻MsPGN的肾小球病变及肾小管间质损伤。     

Synergistic Interaction Between Dexmedetomidine and Ulinastatin Against Vincristine-Induced Neuropathic Pain in Rats

Antimicrotubulin chemotherapeutic agents such as vincristine (VCR), often induce peripheral neuropathic pain. It is usually permanent and seriously harmful to cancer patients' quality of life and can result in the hampering of clinical treatments. Currently, there is no definitive therapy, and many of the drugs approved for the treatment of other neuropathic pain have shown little or no analgesic effect. It is therefore vital to find new and novel therapeutic strategies for patients suffering from chemotherapeutic agent-induced neuropathic pain to improve patients' quality of life. This study shows that intrathecal injections of dexmedetomidine (DEX), or intraperitoneally administered ulinastatin (UTI) significantly reduces Sprague Dawley rats' mechanical allodynia induced by VCR via upregulation of interleukin-10 expression and activating the α2-adrenergic receptor in dorsal root ganglion (DRG). Moreover, when combined there is a synergistic interaction between DEX and UTI, which acts against VCR-induced neuropathic pain. This synergistic interaction between DEX and UTI may be partly attributed to a common analgesic pathway in which the upregulation of interleukin -10 plays an important role via activating α2-adrenergic receptor in rat dorsal root ganglion. The combined use of DEX and UTI does not affect the rat's blood pressure, heart rate, sedation, motor score, spatial learning, or memory function. All of these show that the combined use of DEX and UTI is an effective method in relieving VCR-induced neuropathic pain in rats.

鱼皮胶原蛋白水解液中小分子寡肽的分子量分布测定

目的建立测定鱼皮胶原蛋白水解液中小分子寡肽相对分子量分布的方法。方法采用高效凝胶排阻色谱法用3根TSK-GEL G2000SWXL色谱柱（300 mm×7.8 mm,5μm）串联,室温;流动相为乙腈-0.1%三氟乙酸溶液（15∶85）,流速0.6 mL.min-1,检测波长220 nm。结果在相对分子量149～2 490 Da内,寡肽相对分子量的对数与其保留时间具有良好的线性关系（r=0.995 6）;精密度和重复性RSD均〈0.1%。结论本方法简便准确,重复性好,可作为测定小分子寡肽分子量分布的方法。     

Multimerization and interaction of Toll and Spätzle in Drosophila

The Toll family of receptors is required for innate immune response to pathogen-associated molecules, but the mechanism of signaling is not entirely clear. In Drosophila the prototypic Toll regulates both embryonic development and adult immune response. We demonstrate here that the host protein Sp?tzle can function as a ligand for Toll because Sp?tzle forms a complex with Toll in transgenic fly extracts and stimulates the expression of a Toll-dependent immunity gene, drosomycin, in adult flies. We also show that constitutively active mutants of Toll form multimers that contain intermolecular disulfide linkages. These disulfide linkages are critical for the activity of one of these mutant receptors, indicating that multimerization is essential for the constitutive activity. Furthermore, systematic mutational analysis revealed that a conserved cysteine-containing motif, different from the cysteines used for the intermolecular disulfide linkages, serves as a self-inhibitory module of Toll. Deleting or mutating this cysteine-containing motif leads to constitutive activity. This motif is located just outside the transmembrane domain and may provide a structural hindrance for multimerization and activation of Toll. Together, our results suggest that multimerization may be a regulated, essential step for Toll-receptor activation.