HPLC-ELSD法测定湖北麦冬中主要皂苷的含量

采用蒸发光散射检测器（ＥＬＳＤ）测定了湖北麦冬中山麦冬皂苷Ｂ的含量,结果表明,ＥＬＳＤ是皂苷类化合物较为适宜的检测器。经对不同采收期样品的含量考察,认为湖北麦冬的最佳采收期与传统采收期（清明）相一致。     

11O例离异家庭初中生心理卫生及适应状况的对照研究

目的了解离异家庭初中生心理、人格、社交、学习等状况,探讨影响他们再适应的主要因素.方法对110例研究对象作SCL-90、EPQ、社交回避苦恼量表、学习成绩以及相关因素调查,对适应良好和不良组作特质应对、父母养育方式以及精神卫生、离异时间、抚养对象、亲子关系等对照研究.结果 SCL-90大多数因子分显著高于常模(P＜0.01,P＜0.05),有自杀观念占23%,人格问卷中P、N、E,一个或多个因子高于常模占56%,社交困难占40%,成绩显著低于平均分(P＜0.05).适应不良组的消极应对分、父母严厉惩罚、拒绝否认、干涉过度、母亲偏爱分显著高于适应良好组(P＜0.01,P＜0.05),成绩以及与非监护人关系差(P＜0.05),监护人心理卫生问题多(P＜0.05).而离异时间、抚养对象、人口学指标等无显著差异(P＞0.05),男生个性问题发生率高,成绩差,较女生适应困难.结论研究对象不良心理、社会交往及学习困难发生率高,影响他们再适应的主要因素有:应对方式、父母养育方式和监护人心理状况以及能否获得非监护人的关爱.     

Enhancement of the response to purinergic agonists in P2Y1 transfected 1321N1 cells by antagonists suramin and PPADS

1. We have previously shown that both suramin and pyridoxal-phosphate-6-azophenyl-2′, 4′ disulphonic acid (PPADS) act as antagonists at transfected P2Y₁ receptors. Here we show that under certain experimental conditions these two P2 antagonists can enhance the response to agonists acting at these receptors.
2. The expression of either P2Y₁ or P2Y₂ receptors in 1321N1 human astrocytoma cells results, on a change of medium, in an elevation of basal (no added agonist) accumulation of [³H]-inositol(poly)phosphates([³H]-InsP_x) compared to cells not expressing these receptors. This elevation is much greater in P2Y₁ transfectants than in P2Y₂ transfectants.
3. Both PPADS and suramin reduced this basal level of [³H]-InsP_x accumulation in the P2Y₁ expressing cells.
4. When a protocol was used which required changing the culture medium, antagonists were added at a concentration which reduced the basal accumulation by about 50%, there was a significant stimulation in response to increasing concentrations of 2-methylthioadenosine 5′-triphosphate (2MeSATP), in the absence of antagonists there was no significant effect of the agonist.
5. However, when 2MeSATP was added in the absence of a change of medium and with no antagonist present, there was a several fold increase in [³H]-InsP_x accumulation. These results show that a release of endogenous agonist activity (possibly ATP/ADP) from the P2Y₁ expressing cells can create conditions in which a response to an agonist such as 2MeSATP can only be seen in the presence of a competitive antagonist.

     

Selective attenuation of neuropeptide-Y-mediated contractile responses in blood vessels from patients with diabetes mellitus

Vascular smooth muscle contractile responses to neuropeptide Y, ,ß-methyleneATP and noradrenaline were studied in circular segments of isolated vessels with intact endotheliumin vitro from 12 patients with diabetes mellitus type 2 (NIDDM) and 12 control subjects. The dilatory effect of acetylcholine was used to test the function of the endothelium. Subcutaneous arteries and veins (diameter 0.1–1.1 mm) were obtained during surgery. There was no difference in contractile responses to noradrenaline or ,ß-methyleneATP between diabetic and control vessels. The contractile response to neuropeptide Y, however, was markedly reduced in the diabetic group. The maximal contractile effect (46.0 ± 14.0%,p < 0.05) but not the sensitivity to neuropeptide Y was significantly less in diabetic veins compared to control (107.5 ± 19.6%). Thus, the attenuation of neuropeptide Y responses was present in humans as previously observed in alloxan-induced diabetes mellitus in rabbits. There was no difference in the dilator effect of acetylcholine between the diabetic and the control group in any of the vessel types, indicating that the difference in vascular reactivity to neuropeptide Y was not endothelium-dependent. In conclusion, the present study has shown that the postjunctional effects of neuropeptide Y, a co-transmitter of the peripheral sympathetic nervous system, is selectively attenuated in diabetes mellitus.     

某金矿凿岩工症状自评量表调查分析

探讨局部振动对工人心理,行为功能的影响。方法 应用ＳＣＬ－９０量表及一般症状查体资料,对４０名金矿井正业凿岩机工人及其对照组２０名工人进行了调查分析。结果 与对照组比较,凿岩组工人在耳鸣,听力下降,高血压等方面有显著性意义;症状量表听各项指标均与对照组有显著差异,且在工作后１０年内易发生。结论局部振动可造成工人心理,行为功能的改变及一些症状的出现,二者又可相互作用,进一步加重对工人身心健康的危害。     

列车乘务员SCL—90评定结果分析

采用ＳＣＬ—９０症状自评量表对某铁路分局４６７名列车乘务员的心理卫生状况进行了分析。结果显示总均分、阳性症状均分、阳性项目数、九组症候群因子分、达到或超过中等严重程度的发生频数均显著高于对照组。经多元逐步回归分析,仅细菌总数和二氧化碳对列车乘务员心理卫生状况有一定影响,其原因多与工作环境的不良因素和工作性质有关。     

胸段硬膜外麻醉对神经肽Y的影响

为探讨胸段硬膜外麻醉对患者血浆ＮＰＹ的影响,本文采用放射免疫分析法测定了３１ 例择期上腹部手术病人胸段硬膜外麻醉前后血浆ＮＰＹ的含量。结果显示：麻醉后平均动脉压较麻醉前显著下降（ Ｐ＜０－０１） ,血浆ＮＰＹ则无显著变化（ Ｐ＞ ０－０５）。提示患者处于硬膜外麻醉状态下体内ＮＰＹ 含量的变化与交感神经系统调节具有一定的关系。     

Interaction of ketamine with μ2 opioid receptors in SH-SY5Y human neuroblastoma cells

Purpose. Ketamine is known to interact with opioid receptors. However, because this agent does not produce opioid-like respiratory depression, it might not interact with μ₂ opioid receptors. Therefore, we have studied the interaction of ketamine with μ₂ opioid receptors expressed in SH-SY5Y cells. Methods. SH-SY5Y cells (passage 70–80) were used to obtain ketamine dose-response curves for inhibition of 0.4 nM [³H][d-Ala²,MePhe⁴,Gly(ol)⁵] enkephalin (DAMGO) binding to μ₂ opioid receptors and of forskolin (1 μM)-stimulated cyclic AMP (cAMP) formation. Results. Ketamine displaced [³H]DAMGO binding in SH-SY5Y cells with a K _i of 12.1 μM. However, this concentrations did not inhibit forskolin-stimulated cAMP formation, although at supraclinical concentrations, significant inhibition was observed with an estimated IC₅₀ of 700 μM. Conclusion. The present study indicates that a clinically relevant concentration of ketamine interacts with μ₂ opioid receptors. However, no agonist activity was observed. Received for publication on September 10, 1998; accepted on January 5, 1999     

Melatonin inhibits in vitro serotonergic phase shifts of the suprachiasmatic circadian clock

The suprachiasmatic (SCN) circadian pacemaker generates 24 h rhythms of spontaneous neuronal activity when isolated in an acute brain slice preparation. The isolated pacemaker also retains its capacity to be reset, or phase-shifted by exogenous stimuli. For example, serotonin (5-HT) agonists advance the SCN pacemaker when applied during mid subjective day, while neuropeptide Y (NPY) agonists and melatonin advance the pacemaker when applied during late subjective day. Previous work has demonstrated interactions between NPY and 5-HT agonists, such that NPY can block 5-HTergic phase advances, while 5-HT agonists do not prevent NPY-induced advances. Due to a number of similarities in the actions of melatonin and NPY in the SCN, it seemed possible that melatonin and 5-HT might interact in the SCN as well. Therefore, in this study potential interactions between melatonin and 5-HT agonists were explored. Melatonin inhibited phase advances by the 5-HT agonist, (+)DPAT, and this inhibition was decreased by co-application of tetrodotoxin. Conversely, melatonin was unable to block phase advances by the cyclic AMP analog, 8BA-cAMP. Finally, neither 5-HT agonists nor 8BA-AMP were able to block melatonin-induced phase advances. These results demonstrate a clear interaction between melatonin and 5-HT in the SCN, and suggest that melatonin and NPY may play similar roles with respect to modulating the phase of the SCN circadian pacemaker in rats.     

Neuropeptide families and their receptors: evolutionary perspectives

Examination of families of neuropeptides and their receptors can provide information about phyletic relationships and evolutionary processes. Within an individual a given signal molecule may serve many diverse functions, mediated via subtypes of the receptor which may be coupled to their transduction mechanisms in different ways. The rate of evolution of a peptide may reflect or be reflected in the rate of evolution of its receptor. For example, in the neuropeptide Y (NPY) family, pancreatic polypeptide (PP) shows significant structural diversity, while NPY is highly conserved. Molecular forms of a given subtype of NPY receptor that is selectively activated by NPY (Y1 or Y2 or Y5) are also highly conserved, but the subtype that is primarily activated by PP (Y4), shows remarkable diversity. Also, between receptor subtypes there can be remarkable diversity. This is evident in several neuropeptide families, where a neuropeptide sequence is highly conserved across a wide range of species but where the receptor homology of subtypes with species tends to be much lower than homology between species. For example, human and rat vasopressin are identical, but the human V₁- or V₂-vasopressin receptors are approximately 80% homologous with rat V₁- or V₂-receptors, but within humans or rats the V₁-receptor is less than 50% homologous with the V₂-receptor. Furthermore, duplication of an ancestral gene is thought to have led to the co-presence in eutherian mammals of oxytocin and vasopressin, which have maintained a close structural similarity, yet in many species the oxytocin receptor is only 30 to 50% homologous with vasopressin receptors. Thus it appears that there has been greater evolutionary pressure to conserve the signal molecule, than to conserve the structure of the receptor. Evaluation of the evolution of neuropeptides and their receptors may be useful in determining phyletic relationships. Traditional classification places the guinea pig as a hystricomorph rodent within the same order (Rodentia) as the muriform or myomorph rat and mouse. However, molecular analyses of polypeptides have led to the suggestion that guinea pigs belong to a distinct order. Analysis of several neuropeptide sequences and the Y4 receptor supports this view. In general terms for both neuropeptides and receptors, sequence homology reflects phylogeny and taxonomy as based on morphological features. Within the oxytocin/vasopressin family in which peptides and receptors have been characterised in invertebrate representatives as well as fish and amphibia in addition to mammals, the molecular diversity correlates well with evolutionary diversity.