Development and optimization of an indirect enzyme-linked immunosorbent assay for the determination of Hexoestrol

An indirect enzyme-linked immunosorbent assay (ELISA) for the detection of hexoestrol (HES) was developed, optimized and validated for the analysis of HES in pork. Many parameters, such as the volume ratio of solution A and solution B, colour developing time, pH value, incubation time, the volume ratio of the standard solution and diluted antiserum, blocking solution, blocking condition, coating solution and coating condition were studied and optimized in the paper. The regression equation of the final inhibition curve is y = - 0.3345x + 1.4955, R²=0.9913. The linear range is 0.1-8.1 ng/ml, and the IC₅₀ is 0.671 ng/ml. The specificity of the assay was evaluated by the cross-reactivity rates of six compounds, of which two structurally related compounds had a relatively higher cross-reactivity rate of 25% and 6%. HES was added into a pork sample at 5 ng/g level and then the sample was extracted. The recovery is between 49.6% and 79.2%, and the variation coefficient is 0.164.     

Glutamate acts at NMDA receptors on fresh bovine and on cultured human retinal pigment epithelial cells to trigger release of ATP

Efficient vesicle membrane recycling at presynaptic terminals is pivotal for preventing depletion and maintaining high firing rates in neuronal networks. We used a new approach, based on the combination of spectrally different optical probes, to investigate how stimulation determines the fate of synaptic vesicles after endocytosis. We found that in the small central synapses of rat hippocampal neurones low frequency stimulation (40 action potentials at 2 Hz) targets vesicles preferentially to vesicle pools that were kinetically faster. Vesicles taken up during endocytosis triggered by high frequency stimulation (400 action potentials, 20 Hz) were also placed in the back of the release queue. We performed a spatial analysis of the recycled vesicles in living hippocampal boutons using two spectrally different FM-dyes (FM1-43 and FM5-95). By using these consecutively, vesicles endocytosed by either stimulation protocol were labelled with a different colour. This revealed that the kinetic arrangement was also reflected in the spatial organization of vesicles within the bouton. Next, we identified the postsynaptic site of the active zone by transfecting the neurones with postsynaptic density protein PSD-95-CFP. The data from these triple colour experiments suggest that retrieval after low frequency stimulation keeps vesicles in a more confined region closer to the active zone as identified by PSD-95-CFP expression at the postsynaptic site.     

给药系统

近年来，伴随着药物治疗的快速发展．以药理活性非常强的药物为代表，开发出许多用药时必须给予足够关注的药物，“用药最适化”这一概念逐渐成为人们非常关注的问题。这主要是为了实现用药时的最佳形式。尽可能地根据选择或者需要控制药物的浓度．时间模式。输送到药物的作用表达部位。实现治疗用药的安全性。但是，历来的方法却很难实现这一点，通过利用新的技术和方法调控药物在体内的动态变化，以获得最好治疗效果为中心的药物使用方法和药剂正在开发之中。这就是给药系统，使用可以表达自身概念的语言来命名。虽然都是以各种药物在体内的动态过程作为调控对象，但是还分为①controlled release（调控释放给药）；②开发新的给药途径、克服药物吸收障碍；③靶向给药（targeting）等三个途径。     

Study on hemostatic mechanism of fully soluble hemostatic fiber.

Fully soluble hemostatic fiber (FHF) is made from cotton yarn through a series of chemical reactions with NaOH and chloroacetic acid. The major component of FHF is carboxymethylcellulose. FHF is a kind of biodegradation macromolecule material that can disassociate into a low-molecular-weight compound or a simple substance by hydrolytic and enzymatic courses. The purpose of the present study is to investigate the hemostatic mechanism of FHF. The study indicated that FHF can stop bleeding by physical, chemical and physiological routes. In the physical route, expansion of carboxymethylcellulose in FHF stops bleeding by forming a mechanical clog after contacting with the blood. In the chemical route, the platelets can quickly aggregate around FHF and stimulate releasing and disaggregating reactions, after contacting with the rough surface of FHF, producing thrombus and hemostasis. In the physiological route, gluey particles with negative charges can activate intrinsic coagulation systems by activating the blood coagulation factor XII after FHF dissolution.     

急性心肌梗死患者的心理分析及心理干预

现将我院2002-2005年收治住院的急性心肌梗死患者56例的心理干预及护理体会，报告如下：     

Nerve growth factor and tyrosine kinase A in human salivary adenoid cystic carcinoma: expression patterns and effects on in vitro invasive behavior.

PURPOSE: Perineural invasion is a frequent occurrence in salivary adenoid cystic carcinoma (ACC) and may prevent complete surgical resection. Studies have indicated that nerve growth factor (NGF) and its high-affinity receptor tyrosine kinase A (TrkA) may play a role in perineural invasion in several malignancies in which perineural invasion is observed. The present study was conducted to investigate the expression of NGF and TrkA in salivary ACC and to examine the effects of NGF on adhesion, migration and invasion capacities of a salivary ACC cell line (SACC-83) in vitro. PATIENTS AND METHODS: Expression of NGF and TrkA was explored using immunohistochemistry in paraffin-embedded tissues of 32 cases of salivary ACC. The effects of NGF on in vitro adhesion, migration, and invasion capacities of the SACC-83 cell line were examined using an MTT assay and a modified Boyden chamber assay respectively. RESULTS: In ACC specimens, 31 (96.9%) and 32 (100%) tumors showed immunoreactivity for NGF and TrkA respectively. Significant correlations were found between NGF/TrkA expression levels and perineural invasion (P < .05). In cell adhesion assay, the percent adherences of SACC-83 cells co-cultured with 25 ng/ml NGF at 1.5 hours and 5, 25 ng/ml NGF at 6 hours were significantly higher than that co-cultured with 0 ng/ml NGF (P < .05). However, high concentration of NGF (500 ng/ml) resulted in a significant inhibition of invasion (P < .05). CONCLUSION: Overexpression of NGF and TrkA in human salivary ACC tissues may constitute a reason for perineural invasion in salivary ACC.     

Frequency of seroreactors to Legionella among the patients with pulmonary infections

A prospective study was conducted with patients with pulmonary infections who were consecutively admitted to the three community hospitals in Benghu from July 1986 to May 1987, and to the children's hospital in Nanjing from September 1986 to January 1987. Antibodies to Lpi-8, Lm, Ld, and Lg were measured by the micro-agglutination test. During the study period, 150 adult patients (100 pairs sera) and 212 control healthy people and 110 pairs sera of childhood patients and 173 children without respiratory tract infections were investigated. The diagnosis of legionellosis was based on seroconversion (fourfold rise in titer to greater than 1:32 or static titer of greater than 1:32) and clinical and radiographic features of legionnaires' disease. About 11% legionella infection in hospitalized adult patients with pulmonary infections, and about 5.45% in children with atypical pneumonias.