电磁辐射对小鼠神经系统超微结构影向的分析

目的探讨移动电话的电磁辐射对生物体的影响.方法用大众常用移动电话作为辐射源,工作频率为900MHz,功率密度为1190μW/cm2,在一定范围对小鼠辐射2h/d,30d后把小鼠断颈处死,取出大脑皮层、海马和小脑进行电镜观察分析.结果电镜所见,处理组与对照组小鼠的神经系统的细胞超微结构未见明显异常.结论一定时间内,移动电话的电磁辐射,对小鼠神经系统的细胞超微结构并没有明显影响.     

Study of the mechanism of essential garlic oil inhibiting lnterleukin-1 α-induced monocyte adhesion to endothelial cells

Objective  

To observe the effects of essential garlic oil (EGO) on vascular cell adhesive molecule-1 (VCAM-1) expression of endothelial cells and monocyte-endothelial cell adhesion rate induced by interleukin-l_α(IL-l_α).     

Comparative study of different transplantation methods of adipose tissue-derived stem cells in the treatment of erectile dysfunction caused by cavernous nerve injury

We aimed to compare intracavernosal injection (ICI), tail vein injection (IV), and periprostatic injection (PPI) of adipose-derived stem cells (ADSCs) for their ability to improve erectile function in cavernous nerve injury-induced erectile dysfunction (CNIED) rats and to explore the possible mechanism. Eighty-four male SD rats were divided into the sham group (n = 6), BCNI group (bilateral CN crush injury, n = 6), PBS-ICI group (n = 6), PBS-IV group (n = 6), PBS-PPI group (n = 6), ADSC-ICI group (n = 18), ADSC-IV group (n = 18) and ADSC-PPI group (n = 18). ADSCs were labelled with 5-ethynyl-2′-deoxyuridine (EdU), and six rats each in the ADSC-ICI group, ADSC-IV group, and ADSC-PPI group were sacrificed 2, 7, and 28 days after injection. EdU-labelled ADSCs were tracked by immunofluorescence staining. The intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio, neuronal nitric oxide synthase (nNOS)-positive nerve fibres in the dorsal penile nerve and the smooth muscle/collagen ratio in the cavernosum between groups were also evaluated. ADSCs can significantly improve erectile function through ICI or IV. The two are similar in efficacy and superior to PPI. The mechanism may be that after CN injury, ADSCs are recruited to around the MPG and secrete a variety of neurotrophic factors that promote the repair of the CN, thereby improving erectile function.     

In vivo imaging of neuroblastomas using GD2-targeting graphene quantum dots

BackgroundPatients with neuroblastoma, a common childhood malignancy, often have poor prognosis. It is mandatory to develop an accurate and efficient diagnostic tool for neuroblastomas, so that the treatment can be started early. Graphene quantum dot (GQD), a nanomaterial, can be used to carry proteins, genetic materials, or drugs. GD2, a disialoganglioside, is a surface antigen expressed on neuroblastoma. This study investigated the in vivo targeting and imaging of neuroblastomas using GD2-targeting GQDs.MethodsGQDs were synthesized and conjugated with anti-GD2 antibody (anti-GD2/GQDs). In vitro cytotoxicity of GQDs and anti-GD2/GQDs was studied in human neuroblastoma cells by 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide)-based colorimetric assay. The tumor tracking and imaging of anti-GD2/GQDs in mice were investigated by in vivo imaging system (IVIS).ResultsTreatment with GQDs or anti-GD2/GQDs induced no or mild cytotoxicity in fibroblasts and neuroblastoma cells. After co-incubation, GQDs and anti-GD2/GQDs were located in the cytoplasm and nucleus of neuroblastoma cells, with GQDs showing a blue fluorescence and anti-GD2/GQDs an orange/red emission. The IVIS images demonstrated accumulation of the fluorescence of anti-GD2/GQDs in the subcutaneous tumors in mice 24 h after intravenous injection of anti-GD2/GQDs.ConclusionsAnti-GD2/GQDs may potentially be used for the targeting and imaging of neuroblastomas in vivo.     

二氧化硅法纯化琼脂糖凝胶中的DNA

利用二氧化硅特异地吸附核素的特性，建立了从琼脂糖凝胶中回收ＤＮＡ的方法。结果表明本方法对１３００￣３５００ｂｐ的ＤＮＡ回收效果较好，回收效率达６０％￣７０％，１００￣１５００ｂｐ，３５００￣５０００ｂｐ的ＤＮＡ亦能被有效地回收。通过对回收ＤＮＡ的酶切，连接等实验，证实了所回收的ＤＮＡ片段能够满足进一步的实验要求。该方法简单，快捷，经济，适用，值得推广。     

微量补体反应性溶血测定法

本文报道从酵母多糖活化的急性期患者血浆中分离Ｃ＾－５６复合物，并经ＤＥＡＥ－纤维素ＤＥ－３２阴离子交换层析纯化。利用微孔板和自动微孔板测定仪建立了一种简单，灵敏，准确的微量反应性溶血测定法。     

凝血酶烧伤膏治疗血液病鼻衄的临床观察

目的 为探讨血液病鼻衄的理想处理方法。方法 对２３例治疗组患者采用浸有凝血酶２０００Ｉｕ／ｍｌ的明胶海绵局部敷贴出血点,３～４日后用烧伤膏创面换药;３４例对照组采用凡士林纱条填塞止血。结果 治疗组有效率８６．９％,显效率６９．７％;对照组分别是５８．５％和３５．３％。两种方法有显著性差异（Ｐ〈０．０１）。结论 用凝血酶敷贴出血点及创面烧伤膏换药是治疗血液病鼻衄一种安全、有效的方法。     

Determination of microviscosity and location of 1,3-Di(1-pyrenyl)propane in brain membranes

We determined the microviscosity of synaptosomal plasma membrane vesicles (SPMV) isolated from bovine cerebral cortex and liposomes of total lipids (SPMTL) and phospholipids (SPMPL) extracted from SPMV. Changes in the microviscosity induced by the range and rate of lateral diffusion were measured by the intramolecular excimerization of 1,3-di(1-pyrenyl)-propane (Py-3-Py). The microviscosity values of the direct probe environment in SPMV, SPMTL and SPMPL were 38.17, 31.11 and 27.64 cP, respectively, at 37°C and the activation energies (E_a) of the excimer formation of Py-3-Py in SPMV, SPMTL and SPMPL were 8.236, 7.448 amd 7.025 kcal/mol, respectively. Probe location was measured by polarity and polarizability parameters of the probe Py-3-Py and probe analogues, pyrene, 1-pyrenenonanol and 1-pyrenemethyl-3β-hydroxy-22,23-bisnor-5-cholenate (PMC), incorporated into membranes or solubilized in reference solvents. There existed a good linear relationship between the first absorption peak of the¹L_a band and the polarizability parameter (n ²−1)/(2n ²+1). The calculated refractive index values for SPMV, SPMTL and SPMPL were close to 1.50, which is higher than that of liquid paraffin (n=1.475). The probe location was also determined by using a polarity parameter (f−1/2f¹). Here f=(ε−1)/(2ε+1) is the dielectric constant function and f'=(n ²−1)/(2n ²+1) is the refractive index function. A correlation existed between the monomer fluorescence intensity ratio and the solvent polarity parameter. The probes incorporated in SPMV, SPMTL, and SPMPL report a polarity value close to that of 1-hexanol (ε=13.29). In conclusion, Py-3-Py is located completely inside the membrane, not in the very hydrophobic core, but displaced toward the polar head groups of phospholipid molecules, e.g., central methylene region of aliphatic chains of phospholipid molecules.     

Effect of riluzole on the neurological and neuropathological changes in an animal model of cardiac arrest-induced movement disorder

Posthypoxic myoclonus and seizures precipitate as secondary neurological consequences in ischemic/hypoxic insults of the central nervous system. Neuronal hyperexcitation may be due to excessive activation of glutamatergic neurotransmission, an effect that has been shown to follow ischemic/hypoxic events. Therefore, riluzole, an anticonvulsant that inhibits the release of glutamate by stabilizing the inactivated state of activated voltage-sensitive sodium channels, was tested for its antimyoclonic and neuroprotective properties in the cardiac arrest-induced animal model of posthypoxic myoclonus. Riluzole (4-12 mg/kg i.p.) dose-dependently attenuated the audiogenic seizures and action myoclonus seen in this animal model. Histological examination using Nissl staining and the novel Fluoro-Jade histochemistry in cardiac-arrested animals showed an extensive neuronal degeneration in the hippocampus and cerebellum. Riluzole treatment almost completely prevented the neuronal degeneration in these brain areas. The neuroprotective effect was more pronounced in hippocampal pyramidal neurons and cerebellar Purkinje cells. These effects were seen at therapeutically relevant doses of riluzole, and the animals tolerated the treatment well. These findings indicate that the pathogenesis of posthypoxic myoclonus and seizure may involve excessive activation of glutamate neurotransmission, and that riluzole may serve as an effective pharmacological agent with neuroprotective potential for the treatment of neurological conditions associated with cardiac arrest in humans.