Suppression of Lewis carcinoma metastasis in mice by an interferon-inducing vasodilator curantil

The intravascular (iv) or intramuscular (im) inoculations of a suspension of Lewis carcinoma cells induced metastatic tumor nodules in the lungs of C57Bl/6 mice. The administration of curantil (dipyridamole) (500 mg per 20 g-mouse, per os) once a week beginning one day after iv tumor cells inoculation (2 X 10(5) cells) reduced 4-fold the number of tumor nodules. The administration of curantil one day after im tumor cells inoculation (2 X 10(6) cells) reduced 2-fold the number of tumor nodules. The combined treatment of curantil (4-, 10-days after inoculation) and well-known inducer of interferon poly I:poly C (50 mg per 20 g-mouse, 1-, 7-, 14-days after inoculation tumor cells) had no synergistic effect.     

Regulation by the protein kinase C activator phorbol ester of calcium channels in polymorphonuclear leukocytes

The Quin fluorescence in gamma-hexachlorocyclohexane-stimulated polymorphonuclear leukocytes is rapidly increased, which points to the increase in Ca2+in concentration during leukotriene B4 synthesis in leukocytes. An addition of EGTA and calcium antagonists (nifedipine, verapamil, diltiazem) to cell suspensions does not affect the basal level of internal Ca2+ but results in the inhibition of the gamma-hexachlorocyclohexane-induced Ca2+ increase. Two mechanisms of calcium homeostasis regulation in neutrophils are proposed. One of them, cAMP regulation, is coupled with a potent inhibiting effect of prostacyclin, an adenylate cyclase activator, on Ca2+in increase in stimulated neutrophils. The other one is the activation of protein kinase C catalyzed by 4 beta-phorbol-12 beta-myristate-13 alpha-acetate. The experimental results suggest that such an activation blocks Ca2+ influx into the cells via the closure of Ca2+ channels. The synergism of action of the above mechanisms in the regulation of calcium homeostasis in neutrophils is demonstrated.     

马铃薯糖转运蛋白基因的克隆及表达分析

植物SWEET基因家族是一类糖转运蛋白,在植物的生理活动和生长发育过程中发挥着重要功能。为了解马铃薯SWEET基因的相关信息,探究其在马铃薯不同组织以及在生物胁迫与非生物胁迫下的表达特性。该研究采用同源克隆技术从马铃薯‘青薯9号’中克隆了StSWEET5基因(GenBank登录号为MN295671),其CDS序列长度为717 bp,编码238个氨基酸。系统进化树分析结果表明,StSWEET5与番茄的氨基酸序列相似性最高(97.06%)。qRT-PCR分析表明:StSWEET5基因在马铃薯各组织(根、茎、叶、花、块茎、匍匐茎)中均有表达,且在花中的表达显著高于其他组织;糖胁迫下,StSWEET5基因在根、茎、叶中均有表达,尤其在根中的表达差异最为显著(P0.05)。在晚疫病菌(Phytophthora infestans)诱导后36 h时,表达量达到最高,随后急剧下调。推测StSWEET5基因参与了马铃薯糖胁迫以及响应了晚疫病诱导的过程。     

Evaluation of the prevalence and economic burden of adverse drug reactions presenting to the medical emergency department of a tertiary referral centre: a prospective study

Background  

Adverse drug reactions (ADRs) are now recognized as an important cause of hospital admissions, with a proportion ranging from 0.9–7.9%. They also constitute a significant economic burden. We thus aimed at determining the prevalence and the economic burden of ADRs presenting to Medical Emergency Department (ED) of a tertiary referral center in India     

疣柄牛肝菌属一中国新记录种

报道了采自内蒙古呼伦贝尔市的中国疣柄牛肝菌属1个新记录种,即假褐疣柄牛肝菌Leccinum pseudoscabrum(Kallenb.)utara.。主要特征为菌肉伤后变红到紫褐色,再到黑褐色,基部菌丝体手触后呈紫褐色;具泡状菌丝,呈栅栏状。比较和讨论了该种与相近种在伤后不同的变色反应及菌丝形态。研究标本存放于吉林农业大学菌物标本馆(HMJAU)。     

鞘氨醇-1-磷酸对人脐带间充质干细胞增殖及表面标记物表达的影响

鞘氨醇－1－磷酸（sphingosine－1 phosphate, S1P）是一种脂质信号分子,与细胞增殖、凋亡和迁移等有密切关系．本研究发现,S1P促进人脐带间充质干细胞(human umbilical cord mesenchymal stem cells, hUC－MSCs)增殖,但目前关于其作用信号通路及S1P对hUC－MSCs表面标记表达的影响尚不十分清楚．Real－time PCR检测hUC－MSCs中S1P受体mRNA表达情况,发现在hUC－MSCs中优势表达S1PR1 3,而S1PR4、S1PR5的表达很少．MTT法检测S1PR1/3拮抗剂VPC23019、S1PR2拮抗剂JTE013、S1PR3拮抗剂CAY10444、Gi蛋白抑制剂PTX和ERK抑制剂PD98059对S1P诱导hUC－MSCs增殖的影响．结果显示,VPC23019完全抑制S1P诱导的hUC MSCs增殖,JTE013对此没有明显影响,CAY10444部分抑制S1P诱导的hUC MSCs增殖,PTX、PD98059完全抑制S1P诱导hUC－MSCs增殖．进一步用Western印迹检测ERK1/2磷酸化水平揭示,S1P通过促进ERK1/2磷酸化进而促进hUC MSCs增殖．流式细胞术检测发现,S1P对hUC MSCs表面标记物(CD45、CD34、CD90、CD29、CD105、CD44、CD73、CD71)表达没有明显影响．本研究证明,S1P通过S1PR1/3、Gi偶联蛋白及ERK1/2信号通路促进hUC MSCs增殖,而对hUC MSCs表面标记物表达无明显影响．     

Spatial summation processes in the receptive fields of visually driven neurons of the cat's cortical area 21a

The spatial summation in receptive fields (RF) of single neurons in cat's extrastriate area 21a was investigated as a basic neurophysiological substrate for central integration processing of visual information. The results showed that the majority of investigated neurons changed their response patterns with gradual increase of applied stimulus size. In approximately 82% of cases the suppression of neuron discharges was observed when the length of the moving strip exceeded that of the RF. In some neurons the increased size of the moving stimulus leads to the changes in the RF substructure. Receptive fields of neurons recorded at the same microelectrode penetration depth showed a great variety of RF superpositions distributed in a spatially asymmetric manner. As a result, every single RF consists of multiple sub-regions within the RF, differing from each other by the number of superimposed RF-s (density factor). We suggest that such complex spatial organization of the RF provides the neurophysiological basis for central integration processing of the visual information.