Placental tissue stem cells and their role in neonatal diseases

Neonatal diseases such as hypoxic ischemic encephalopathy, diseases of prematurity and congenital disorders carry increased morbidity and mortality. Despite technological advancements, their incidence remains largely unabated. Stem cell (SC) interventions are novel therapies in the neonatal world. In pre-clinical models of neonatal diseases, SC applications have shown encouraging results. SC sources vary, with the bone marrow being the most utilized. However, the ability to harvest bone marrow SCs from neonates is limited. Placental-tissue derived SCs (PTSCs), provide an alternative and highly attractive source. Human placentas, the cornerstone of fetal survival, are abundant with such cells. Comparing to adult pools, PTSCs exhibit increased potency, decreased immunogenicity and stronger anti-inflammatory effects. Several types of PTSCs have been identified, with mesenchymal stem cells being the most utilized population. This review will focus on PTSCs and their pre-clinical and clinical applications in neonatology.     

Spatial and temporal variations in the magnetic fields produced by human gastrointestinal activity

Magnetoenterography (MENG) is a new, non-invasive technique that measures gastrointestinal magnetic signals near the body surface. This study was undertaken to evaluate the temporal and spatial characteristics of the magnetic signals generated by gastric and duodenal slow wave activity. The gastrointestinal magnetic fields of eight normal subjects were measured for 60 minutes in both the fasting and fed state using 36 magnetic sensors simultaneously. The results were displayed as a succession of maps over time showing the temporal evolution of the spatial distribution of the signal over the upper abdomen. In all subjects, slow wave activity of the stomach centred at 3.0 +/- 0.5 cycles min-1 in both the fasting and fed state was observed. The duodenal signal at 11.0 +/- 1.0 cycles min-1 was observed in four subjects. The spatial distribution of these two signals is distinctly different. The observed spatial and temporal variations are described in terms of a model used previously to explain the potentials observed in electrogastrography (EGG).     

中药配合低能量氦—氖激光血管内照射为主治疗缺血性中风疗效观察

目的：观察中药配合低能量氦－氖激光血管内照射为主治疗缺血性中风疗效。方法：治疗组：用中药配合低量氦－氖激光血管内照射为主治疗缺血性中风６９例;对照组：用降纤酶、尼莫通治疗缺血性中风４２ 例。结果：治疗组基本痊愈４８ 例,显效８例,有效７例,无效５ 例,恶化１ 例,有效率为９１．３０％ 。对照组基本痊愈２０例,显效１例,有效９ 例,无效１１ 例,恶化１例,有效率为７１．４３％ 。经χ２ 检验,χ２＝ ７．６,Ρ＜ ０．０１,有显著差异。结论：治疗组中药配合低能量氦－氖激光血管内照射为主治疗缺血性中风综合疗效明显优于对照组用降纤酶和尼莫通治疗缺血性中风     

大鼠局灶性脑缺血模型及其与C反应蛋白变化的关系

目的 改进大鼠大脑中动脉梗塞法,建立更接近于临床缺血性脑卒中及其再扩灌注的可靠模型,并观察其与血甭Ｃ反应蛋白变化的。方法沿大鼠右颈内动脉插入长２．１￣２．３ｃｍ直径０．２０５ｍｍ的单股尼龙丝,直达大脑中动脉起始部开口,阻断其血流,观察大鼠神经病学改变及脑组织形态学变化,并测定血清Ｃ反应蛋白含量。结果 术后大鼠表现特殊体态及典型追尾征,６ｈ大脑中动脉供血区出现缺血性外观（ＴＴＣ染色）及相应组织学变化     

戈米辛J和异型南五味子丁素对大鼠胸主动脉的作用

目的研究由南五味子属药用植物分离的戈米辛Ｊ（ｇｏｍｉｓｉｎＪ,ＧＪ）和异型南五味子丁素（ｈｅｔｅｒｏｃｌｉｔｉｎＤ,ＨＤ）对血管平滑肌的作用。方法采用离体大鼠胸主动脉标本,观察他们对高钾去极化收缩和对ＣａＣｌ２、ＮＡ量效曲线的影响。结果ＧＪ和ＨＤ能抑制ＫＣｌ所致的收缩,其ＩＣ５０（９５％可信限）分别为３．８（２．４～５．９）和７．５（１．４～３９）μｍｏｌ／Ｌ;ＧＪ和ＨＤ能使ＣａＣｌ２量效曲线右移,最大效应降低,其ｐＤ′２值分别为５．１３±０．０７和４．７７±０．１８;ＧＪ和ＨＤ也可使ＮＡ量效曲线右移和最大效应降低,其ｐＤ′２值分别为３．７２±０．２３和３．３１±０．２７。结论ＧＪ和ＨＤ能抑制ＫＣｌ、ＣａＣｌ２和ＮＡ产生的血管收缩,而且对ＣａＣｌ２的致缩作用强于对ＮＡ的收缩作用,提示他们具有钙拮抗活性。     

Divalent Cations Modulate the Inhibitory Substrate Properties of Murine Glia-derived J1-160 and J1-180 Extracellular Matrix Glycoproteins for Neuronal Adhesion

J1-160 and J1-180 are developmentally late appearing J1 extracellular matrix glycoproteins derived from oligodendrocytes. They prevent adhesion of neurons (but not of astrocytes or fibroblasts) when offered as a substrate in mixture with laminin (Pesheva et al., J. Cell Biol., 109, 1765 - 1778, 1989). In the present study we have examined the influence of divalent cations on the inhibitory substrate properties of J1-160/180 glycoproteins towards adhesion of neurons. By metal chelate affinity chromatography, we show that J1-180, but not J1-160, binds Ca2+, while both J1 components are capable of binding Zn2+ and other divalent metal ions. Divalent cation binding was observed by gel filtration, aggregation assays with coated latex beads and electron microscopic examination to elicit aggregation of the molecules. Divalent cation binding also affects their non-permissive substrate properties towards neurons from early postnatal mouse cerebellum. Without divalent cations, J1-160 and J1-180 are inhibitory for substrate adhesion of neurons independently of the adhesive substrate present (laminin or poly-l-lysine). This effect is neutralized when J1-180 is preincubated with Ca2+ or Zn2+ prior to coating as substrate. In contrast, preincubation with Ca2+ ions does not affect the inhibitory substrate properties of J1-160 under these conditions. These observations show that J1-160/180 molecules may undergo self-aggregation in a divalent cation-dependent mechanism, which correlates with the neutralization of their inhibitory effect on neuronal adhesion. The aggregation state of the molecules may thus influence the process of myelination by a homophilic binding mechanism and determine the effectiveness of neurite extension during central nervous system development and under traumatic conditions in the adult.     

早期小剂量多巴胺治疗新生儿缺氧缺血性脑病

目的　观察早期应用小剂量多巴胺治疗新生儿缺氧缺血性脑病 (HIE)的疗效。方法　在常规治疗基础上 ,治疗组患儿早期应用多巴胺 5μg·kg- 1 ·min- 1 静脉滴注。结果　治疗组疗效显著优于对照组 ,P<0 0 1 ,治疗组患儿治疗 5～ 7d后全部痊愈出院。结论　早期应用小剂量多巴胺治疗新生儿缺氧缺血性脑病可降低病死率 ,缩短疗程     

一氧化氮与光化学法诱导大鼠脑缺血早期损伤的关系和绞股蓝总皂苷对脑缺血损伤的保护作用

目的：探讨一氧化氮(NO)与光化学法诱导大鼠脑缺血早期损伤的关系和绞股蓝总皂苷(Gyp)对脑缺血损伤的保护作用。方法：应用光化学法诱导大鼠大脑中动脉栓塞(MCAO)模型，观察氧合血红蛋白(OHb)和Gyp对MCAO后脑梗死范围，脑组织含水量、NO及超氧化歧化酶(SOD)、脂质过氧化产物TBARS含量的影响。结果：MCAO6h可导致大鼠局部脑组织明显梗死、脑水肿，同时SOD活力下降，TBARS含量升高，NO释放减少。OHb能进一步强化上述改变而Gyp能逆转上述变化。结论：脑内过氧化反应水平增高导致早期NO含量减少是脑缺血形成的重要原因之一，Gyp可通过影响脑缺血损伤早期脑内NO水平发挥对脑缺血的保护作用。     

黄连花中两个新的三萜皂苷黄连花中两个新的三萜皂苷

目的对黄连花(Lysimachia davurica Ledeb.)全草的三萜皂苷成分进行分离和结构鉴定。方法通过大孔树脂纯化,硅胶和反相硅胶色谱分离正丁醇萃取物物中的三萜皂苷;利用多种波谱技术并结合酸水解方法鉴定其化学结构。结果分离鉴定了2个三萜皂苷,其结构分别为3β,16α,29-三羟基-13,28-环氧-齐墩果烷-3-O-β-D-吡喃葡糖基-(1→2)-β-D-吡喃葡糖酸甲酯苷(I),3β,16α,28-三羟基-齐墩果-12-烯-3-O-｛β-D-吡喃葡糖基(1→2)-β-D-吡喃葡糖醛酸｝-28-O-β-D-吡喃葡糖苷(II)。结论化合物I和II为新的三萜皂苷,分别命名为黄连花皂苷D和J。     

克拉霉素的极谱催化波及其应用

目的建立灵敏快速测定克拉霉素的新方法。方法基于氧化剂存在时克拉霉素产生的极谱催化波,用线性单扫描极谱法快速测定克拉霉素。结果在0.24 mol·L^-1 KH₂PO₄-Na₂HPO₄ (pH 6.81)支持电解质中，克拉霉素于-0.79 V (vs SCE)电位处产生1个还原波。加入过二硫酸钾后，该还原波峰电流增加约20倍，峰电位基本不变，产生一极谱催化波。其二阶导数峰电流i_p″与克拉霉素的浓度在4.0×10^-7-5.0×10^-5mol·L^-1呈良好线性关系(r=0.999 1,n=10)，检出限为2.0×10^-7 mol·L^-1。结论该方法可用于药剂中克拉霉素含量的测定。