Transient receptor potential channel A1 involved in calcitonin gene-related peptide release in neurons

Transient receptor potential channel A1 is one of the important transducers of noxious stimuli in the primary afferents, which may contribute to generation of neurogenic inflammation and hyperalgesia. The present study was designed to investigate if activation of transient receptor potential channel A1 may induce calcitonin gene-related peptide release from the primary afferent neurons. We found that application of allyl isothiocyanate, a transient receptor potential channel A1 activator, caused calcitonin gene-related peptide release from the cultured rat dorsal root ganglion neurons. Knock- down of transient receptor potential channel A1 with an antisense oligodeoxynucleotide prevented calcitonin gene-related peptide release by allyl isothiocyanate application in cultured dorsal root ganglion neurons. Thus, we concluded that transient receptor potential channel A1 activation caused calcitonin gene-related peptide release in sensory neurons.

Blockade of transient receptor potential cation channel subfamily V member 1 promotes regeneration after sciatic nerve injury

The transient receptor potential cation channel subfamily V member 1（TRPV1） provides the sensation of pain（nociception）. However, it remains unknown whether TRPV1 is activated after peripheral nerve injury, or whether activation of TRPV1 affects neural regeneration. In the present study, we established rat models of unilateral sciatic nerve crush injury, with or without pretreatment with AMG517（300 mg/kg）, a TRPV1 antagonist, injected subcutaneously into the ipsilateral paw 60 minutes before injury. At 1 and 2 weeks after injury, we performed immunofluorescence staining of the sciatic nerve at the center of injury, at 0.3 cm proximal and distal to the injury site, and in the dorsal root ganglia. Our results showed that Wallerian degeneration occurred distal to the injury site, and neurite outgrowth and Schwann cell regeneration occurred proximal to the injury. The number of regenerating myelinated and unmyelinated nerve clusters was greater in the AMG517-pretreated rats than in the vehicle-treated group, most notably 2 weeks after injury. TRPV1 expression in the injured sciatic nerve and ipsilateral dorsal root ganglia was markedly greater than on the contralateral side. Pretreatment with AMG517 blocked this effect. These data indicate that TRPV1 is activated or overexpressed after sciatic nerve crush injury, and that blockade of TRPV1 may accelerate regeneration of the injured sciatic nerve.

Transient axonal glycoprotein-1 induces apoptosisrelated gene expression without triggering apoptosis in U251 glioma cells

Previous studies show that transient axonal glycoprotein-1, a ligand of amyloid precursor pro- tein, increases the secretion of amyloid precursor protein intracellular domain and is involved in apoptosis in Alzheimer＇s disease. In this study, we examined the effects of transient axonal glyco- protein-1 on U251 glioma cells. 3-（4,5-Dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide assay showed that transient axonal glycoprotein-1 did not inhibit the proliferation of U251 cells, but promoted cell viability. The terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that transient axonal glycoprotein-1 did not induce U251 cell apoptosis. Real-time PCR revealed that transient axonal glycoprotein-1 substantially upregulated levels of amyloid precursor protein intracellular C-terminal domain, and p53 and epidermal growth factor recep- tor mRNA expression. Thus, transient axonal glycoprotein-1 increased apoptosis-related gene expression in U251 cells without inducing apoptosis. Instead, transient axonal glycoprotein-1 promoted the proliferation of these glioma cells.

流动青少年性行为及避孕措施选择的因素分析

目的:了解流动青少年性行为现况及避孕措施选择的影响因素,为开展流动人口性与生殖健康教育提供科学依据。方法:采用自编结构式匿名问卷对北京、广州、济南4 389名流动青少年进行自填式问卷调查。结果:33.4%(1453/4354)的流动青少年报告有性行为,未婚者性行为发生率为27.5%(1066/3880),其中男性37.8%(579/1533),女性20.7%(487/2 347);避孕措施使用率为44.8%(642/1432),安全套为首选的避孕措施;未婚者中有31.1%(322/1034)报告有妊娠史,29.7%(307/1034)报告有流产史。文化程度(OR=1.555)、婚姻状况(OR=0.432)、性伴侣数(OR=0.683)和性病预防知识得分(OR=1.758)是流动青少年是否使用避孕措施的影响因素。结论:流动青少年性行为发生率较高,避孕措施使用率较低,并引发生殖健康问题,应加强对其进行生殖健康教育,提高有效避孕措施的选择。

Use of various CT imaging methods for diagnosis of acute ischemic cerebrovascular disease

Thirty-four patients with cerebral infarction and 18 patients with transient ischemic attack were examined by multi-slice spiral CT scan, CT perfusion imaging, and CT angiography within 6 hours after onset. By CT perfusion imaging, 29 cases in the cerebral infarction group and 10 cases in the transient ischemic attack group presented with abnormal blood flow perfusion, which corresponded to the clinical symptoms. By CT angiography, various degrees of vascular stenosis could be detected in 41 patients, including 33 in the cerebral infarction group and eight in the transient ischemic attack group. The incidence of intracranial artery stenosis was higher than that of extracranial artery stenosis. The intracranial artery stenosis was located predominantly in the middle cerebral artery and carotid artery siphon, while the extracranial artery stenosis occurred mainly in the bifurcation of the common carotid artery and the opening of the vertebral artery. There were 34 cases （83%） with convict vascular stenosis and perfusion abnormalities, and five cases （45%） with perfusion abnormalities but without convict vascular stenosis. The incidence of cerebral infarction in patients with National Institutes of Health Stroke Scale scores 〉 5 points during onset was significantly higher than that in patients with National Institutes of Health Stroke Scale scores 〈 5 points. These experimental findings indicate that the combined application of various CT imaging methods allows early diagnosis of acute ischemic cerebrovascular disease, which can comprehensively analyze the pathogenesis and severity of acute ischemic cerebrovascular disease at the morphological and functional levels.

Two outward potassium current types are expressed during the neural differentiation of neural stem cells

The electrophysiological properties of potassium ion channels are regarded as a basic index for determining the functional differentiation of neural stem cells. In this study, neural stem cells from the hippocampus of newborn rats were induced to differentiate with neurotrophic growth factor, and the electrophysiological properties of the voltage-gated potassium ion channels were observed. Immunofluorescence staining showed that the rapidly proliferating neural stem cells formed spheres in vitro that expressed high levels of nestin. The differentiated neurons were shown to express neuron-specific enolase. Flow cytometric analysis revealed that the neural stem cells were actively dividing and the percentage of cells in the S ＋ G2/M phase was high. However, the ratio of cells in the S ＋ G2/M phase decreased obviously as differentiation proceeded. Whole-cell patch-clamp re- cordings revealed apparent changes in potassium ion currents as the neurons differentiated. The potassium ion currents consisted of one transient outward potassium ion current and one delayed rectifier potassium ion current, which were blocked by 4-aminopyridine and tetraethylammonium, respectively. The experimental findings indicate that neural stem cells from newborn rat hippo- campus could be cultured and induced to differentiate into functional neurons under defined condi- tions in vitro. The differentiated neurons expressed two types of outward potassium ion cur＇ents similar to those of mature neurons in vivo.

厦门市外来务工人员子女小学高年级学生青春期健康教育现状

目的了解外来务工人员子女小学高年级学生对青春期健康知识知晓情况,为在小学生中深入开展青春期健康教育提供依据。方法 2014年6月选取厦门市某外来务工人员子女小学五六年级所有学生进行青春期健康知识问卷调查。结果高年级小学生中有月经来潮的女生占被调查人数的23.76%;出现首次遗精的男生占被调查人数的17.39%,学生获取青春期健康知识的来源于家长和老师的占82.87%,获取青春期健康知识的方式以别人的口述为主(37.50%)。不同年级男女生对青春期健康知识的知晓情况略有差异,对青春期生理变化和健康知识的态度也各不相同,多数学生希望开设青春期健康教育课程为他们答疑解惑。结论外来务工人员子女小学高年级学生的青春期健康教育知识相对贫乏,针对不同年龄、不同性别外来务工人员子女的生理、心理特点,进行有针对性地开展青春期健康教育是当务之急。