Spinal Cord Stimulation in a Mouse Chronic Neuropathic Pain Model

Objective. Development of a spinal cord stimulation (SCS) system in a mouse model of chronic neuropathic pain. Materials and Methods. Male C57BL/6 mice (N = 6) underwent a partial ligation of the sciatic nerve. Development of mechanical hyperalgesia was tested using the withdrawal response to tactile stimuli with the von Frey test. An SCS system was implanted on day 14. On day 16, the mice were stimulated for 30 min (f = 50 Hz; pulse width 0.2 msec and stimulation at 2/3 of motor threshold). Repeated measure analysis of variance (anova ) and paired Student's t‐test with Bonferroni correction were used to evaluate the development of mechanical hyperalgesia and the therapeutic effect of SCS. Results. Five out of six mice developed marked mechanical hyperalgesia in the nerve‐lesioned paw that persisted for the duration of the study (16 days). No changes contralateral to the injury were observed. In four out of five mice, a successful implantation of the electrodes followed by stimulation was achieved. Then, SCS resulted in a fast and robust increase of withdrawal threshold back to pre‐injury levels. After termination of the SCS, the withdrawal threshold of the ipsilateral paw slowly decreased. No effect of SCS on the contralateral paw was noted. Conclusion. The development of a mouse SCS system is described that is practical in use, is reproducible, and shows a comparative therapeutic effect in treatment of chronic neuropathic pain as reported in rat.     

Macrophage Depletion Suppresses Cardiac Allograft Vasculopathy in Mice

Cardiac allograft vasculopathy (CAV) is a major source of late posttransplant mortality. Although numerous cell types are implicated in the pathogenesis of CAV, it is unclear which cells actually induce the vascular damage that results in intimal proliferation. Because macrophages are abundant in CAV lesions and are capable of producing growth factors implicated in neointimal proliferation, they are leading end-effector candidates. Macrophages were depleted in a murine heterotopic cardiac transplant system known to develop fulminant CAV lesions. C57BL/6 hearts were transplanted into (C57BL/6 x BALB/c)F(1) recipients, which then received anti-macrophage therapy with intraperitoneal carrageenan or i.v. gadolinium. Intraperitoneal carrageenan treatment depleted macrophages by 30-80% with minimal effects upon T, B or NK cells as confirmed by flow cytometry and NK cytotoxicity assays. Carrageenan treatment led to a 70% reduction in the development of CAV, as compared to mock-treated controls (p = 0.01), which correlated with the degree of macrophage depletion. Inhibition of macrophage phagocytosis alone with gadolinium failed to prevent CAV. Macrophages may represent the end-effector cells in a final common pathway towards CAV independent of T-cell or B-cell alloreactivity and exert their injurious effects through mechanisms related to cytokine/growth factor production rather than phagocytosis.     

野战背负式净水机的研制与应用

自行研制了一套可以背负式的野战净水机，采用脚踏为装置提供动力，采用陶瓷膜分离及KDF-活性炭吸附联合净水工艺，产水质量符合国际及军队饮用水标准。装置体积小，重量轻，携带方便，可充分满足野战、救灾用水的需求，十分适合推广。     

板蓝根磷脂对内毒素血症小鼠巨噬细胞膜脂流动性的影响

目的　以小鼠内毒素血症为模型 ,观察板蓝根磷脂对内毒素血症小鼠巨噬细胞膜脂流动性的保护作用。方法　小鼠分为板蓝根氯仿提取物预处理组、磷脂脂质体预处理组、板蓝根磷脂脂质体预处理组和内毒素血症对照组。各组按照上述次序分别给予腹腔注射 5ml/kg相应药物 ,预处理 18h后腹腔注射内毒素 6mg/kg。 6h后处死小鼠 ,观察细胞膜脂流动性的变化。结果　板蓝根氯仿提取物对内毒素血症小鼠巨噬细胞膜脂流动性的保护作用没有达到具有统计学意义的程度 (P >0 .0 5 ) ,磷脂脂质体对膜脂流动性具有保护作用 (P <0 .0 5 ) ,但两者之间并没有统计学上的差别 (P >0 .0 5 ) ;板蓝根磷脂对内毒素血症小鼠细胞膜脂流动性具有明显的保护作用 (P <0 .0 1) ,优于单独使用板蓝根氯仿提取物 (P <0 .0 5 )或磷脂脂质体 (P =0 .0 5 )。结论　板蓝根磷脂脂质体对内毒素血症小鼠巨噬细胞膜脂流动性的保护作用优于单独使用板蓝根氯仿提取物或磷脂脂质体     

Leukaemia Inhibitory Factor or Related Factors Promote the Differentiation of Neuronal and Astrocytic Precursors within the Developing Murine Spinal Cord

Previously we have shown that leukaemia inhibitory factor (LIF) potentiates the development of murine spinal cord neurons in vitro , suggesting that it, or related factors, may play an important regulatory role in neuronal development. We have further investigated this role and show here that the generation of neurons in cultures of embryonic day 10 spinal cord cells is inhibited by antibodies to the β subunit of the LIF receptor. Since there are more undifferentiated precursors in antibody-treated cultures than in control and LIF-treated cultures, it is concluded that the primary action of LIF, or related molecules, is to promote neuronal differentiation, not precursor survival. In addition, the failure of LIF to support neuronal survival in the period immediately following differentiation suggests that the increased numbers of neurons generated with LIF are not attributable to its neurotrophic action. By selecting neuronal precursors on the basis of their inability to express class I major histocompatibility complex molecules, it was shown that LIF acted directly upon these cells and not via an intermediary cell. LIF also appears to be involved in regulating the differentiation of astrocytes, since it increases the number of glial fibrillary protein (GFAP)-positive cells present in the cultures and since the spontaneous production of GFAP-positive cells is blocked by antibodies to the LIF β receptor. These findings suggest that LIF or related factors promote the differentiation of neural precursors in the spinal cord, but that they are not involved in preferentially promoting precursors down a specific differentiation pathway.     

A p65/p95 Neural Surface Receptor is Expressed at the S-G2 Phase of the Cell Cycle and Defines Distinct Populations

A surface receptor complex of M _r˜65 000 (p65) and ˜95 000 (p95) is expressed in cells of the central nervous system of mice. This receptor is recognized by monoclonal antibody 87.92.6 or by reovirus type 3 haemagglutinin as unnatural ligands. The p65/p95 receptor is expressed mostly in neural embryonic precursors undergoing proliferation, especially those in the S-G₂ phase of the cell cycle. Receptor expression decreases progressively throughout embryogenesis to low but detectable levels in the adult brain. Biochemical characterization revealed that the neural p65/p95 receptor complex is indistinguishable from the p65/p95 receptor expressed in T cells, where receptor ligation leads to a mitogenic block. In neural and lymphoid tissues the p65/p95 receptor (or an associated protein) possesses a tyrosine kinase enzymatic activity. Receptor ligation in neural cells resulted in the rapid tyrosine phosphorylation of cellular proteins which are different from substrates phosphorylated in T cells. Differential substrate coupling to the receptor may account for differences in signal transduction and biology between neural cells and T cells. Further study of this receptor complex may help define important features of neural proliferation, differentiation and survival.     

MPTP对鼠肝脂质过氧化作用的影响

本文报道给C57小鼠腹腔注射不同剂量1-甲基-4-苯基-1,2,3,6-四氢吡啶(MPTP)后,发现组3(MPTP35 mg/kg,每天一次,共7天)鼠肝匀浆、线粒体和微粒体的膜丙二醛含量明显增加,与对照组相比分别增加70.5%,67%和51.4%(P<0.01),而组1(MPTP 35mg/kg,每4小时一次,共3次)和组2(MPTP35mg/kg,每天一次,共4天)鼠肝丙二醛含量与对照组相近。结果表明MPTP有明显地促进鼠肝脂质过氧化的作用,并与其剂量有关。     

Synergistic actions of the vitamin D analogue MC 1288 and 15-deoxyspergualin in xenotransplantation

Abstract: The vitamin D analogue MC 1288 (20-epi-1α,25-dihydroxycholecalciferol) effectively postpones rejection of cardiac, intestinal, skin, and aortic allografts. MC 1288 binds to the vitamin D receptor and is thus assumed to exert its immunosuppressive effects via the same mechanisms as 1α,25-dihydroxycholecalciferol, the active form of vitamin D. 1α,25-Dihydroxycholecalciferol has been demonstrated to inhibit the production of various cytokines (interleukin-2, interferon-γ, granulocyte macrophage colony-stimulating factor, and interleukin-12) and to prevent B lymphocyte secretion of immunoglobulins. In the present study MC 1288 was evaluated for its ability to prevent rejection of mouse-to-rat cardiac xenografts, alone and in combination with 15-deoxyspergualin (DSG). Combined treatment with MC 1288 (given days -1 to 9) and DSG (given day -1 and onward) postponed rejection from day 3.0 (untreated recipients) until day 19.5. In rats treated with MC 1288 or DSG as monotherapy, rejection occurred after 3.0 and 7.5 days, respectively. Functioning grafts, obtained on day 9 from recipients treated with MC 1288 and DSG in combination, displayed an almost normal morphology without any obvious deposition of immunoglobulins in the vessels of the grafts and with just a few infiltrating cells. Thus, we have demonstrated synergistic actions of MC 1288 and DSG in delaying rejection of xenografts. Analysis of cellular infiltration, immunoglobulin deposition and graft survival times in the various treatment groups indicate a combined inhibitory effect of these two drugs on the level of macrophage effector function, direct or indirect via T lymphocytes, as well as on antibody production.     

H^＋—ISFET的性能特点及应用研究

本文报道由我们研制的氢离子半导体传感器的性能特点，并与普通离子选择电极（玻璃电极）比较。Ｈ＾＋－ＩＳＦＥＴ具有体积小、取样少、快速、稳定、全固体化、不用预先活化等优点，对氢离子的敏感性也优于普通玻璃电极。本文还成功地将Ｈ＾＋－ＩＳＦＥＴ应用于有复杂成分并存的尿、血及其他生物材料的ｐＨ值测试，并改进胆碱酯酶活力测定方法，将Ｈ＾＋－ＩＳＦＥＴ应用于有机磷中毒后胆碱酯酶活力的快速定量测定。