Expression of ECM-Tenascin in Ethylnitrosourea-Induced Rat Glioma

Tenascin (TN) is a major extracellular matrix glycoprotein that shows a restricted distribution during fetal organogenesis and is also involved in tumor proliferation and invasion. In this study, the expression of TN and fibronectin (FN) in experimental glioma and the possible role of TN in the proliferation and infiltration of rat glioma were investigated. As a result, the tumor mesenchyme in rat gliomas of various sizes and types was found to be negative for both TN and FN. The frequency of TN-positive vessels was significantly higher in anaplastic glioma than in oligodendroglioma. Furthermore, strong TN immunoreaction was noted in the cytoplasm of anaplastic glioma cells, as was strong TN positivity in the cytoplasm and processes of reactive astrocytes. The distribusion of TN was similar to that of FN, but weak FN positivity was observed only in the cytoplasm of some tumor cells. Thus a positive correlation was observed between the frequency of TN positivity and the proliferation or anaplastic changes and malignancy of rat glioma

A trial of patient-oriented problem-solving system for immunology teaching in China: a comparison with dialectic lectures

BACKGROUND: The most common teaching method used in China is lecturing, but recently, efforts have been widely undertaken to promote the transition from teacher-centered to student-centered education. The patient-oriented problem-solving (POPS) system is an innovative teaching-learning method that permits students to work in small groups to solve clinical problems, promotes self-learning, encourages clinical reasoning and develops long-lasting memory. To our best knowledge, however, POPS has never been applied in teaching immunology in China. The aim of this study was to develop POPS in teaching immunology and assess students’ and teachers’ perception to POPS. METHODS: 321 second-year medical students were divided into two groups: I and II. Group I, comprising 110 students, was taught by POPS, and 16 immunology teachers witnessed the whole teaching process. Group II including the remaining 211 students was taught through traditional lectures. The results of the pre- and post-test of both groups were compared. Group I students and teachers then completed a self-structured feedback questionnaire for analysis before a discussion meeting attended only by the teachers was held. RESULTS: Significant improvement in the mean difference between the pre- and post-test scores of those in Groups I and II was seen, demonstrating the effectiveness of POPS teaching. Most students responded that POPS facilitates self-learning, helps them to understand topics and creates interest, and 88.12% of students favored POPS over simple lectures. Moreover, while they responded that POPS facilitated student learning better than lectures, teachers pointed out that limited teaching resources would make it difficult for wide POPS application in China. CONCLUSIONS: While POPS can break up the monotony of dialectic lectures and serve as a better teaching method, it may not be feasible for the current educational environment in China. The main reason for this is the relative shortage of teaching resources such as space, library facilities and well-trained teachers

Effects of Cadmium as a Possible Endocrine Disruptor upon the Serum Level of Sex Steroids and the Secretion of Gonadotropins from Pituitary in Adult Rats

Objective: The objective of this study is to assess the effect of cadmium (Cd) upon the female reproductive system by investigating the serum levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH) as well as sex steroids such as estradiol (E2) and progesterone (P). Materials and Methods: Sprague-Dawley (SD) female rats were daily injected subcutaneously with CdCl2 for 7 or 14 days at a dose of 0,0.5 and 1.0 mg /Kg body-weight (BW) and the serum levels of FSH, LH, E2 and P were measured by radioimmunoassay. Also, the levels of FSH and LH in the presence or absence of extraneously added gonadotropin-releasing hormone (GnRH) were determined in the similarly treated rats. Results: Although the FSH and LH levels were not changed by CdCl2 administration, the serum concentration of E2 was significantly decreased by the injection with both high and low doses of CdCl2. In some conditions the serum P level was also decreased. To examine the reactivity of pituitary cells to GnRH in CdCl2 -treated rats, we measured the serum levels of FSH and LH in the presence or absence of extraneously added GnRH and then found that although the secretion of FSH and LH was increased more or less by GnRH administration in any combinations, the increase in the serum LH level of CdCl2 -treated rats was significantly lower than that of control rats. Conclusion: Cd may decrease the reactivity of LH cells to GnRH, resulting in lower serum levels of E2 and P through the disorder of ovarian cycles

Study on the Relationship of Indoor Air Quality Indexes by Correspondence Analysis and Homogeneity Analysis

We investigated the relationships among air quality indexes, such as the total number of bacteria "BAC", concentration of carbon dioxide "CO2", relative humidity "HUM", concentration of negative ion "NI" and opening time "TIM" in the environment of indoor public place. The data were divided into 3 levels based on its percentile and analyzed by correspondence analysis (ANACOR) and homogeneity analysis (HOMALS) in SPSS 8.0/10.0. Using these methods, we analyzed among 2 variables and their 3 levels, there were the relationships between BAC and CO2, CO2 and TIM, and BAC and TIM. When analyzing by HOMALS, among 3 variables and their 3 levels, there were some similar relationships: BAC, CO2 and TIM; BAC, CO2 and NI. The increase of CO2 and SAC were changed with TIM. The higher CO2 tended to increase BAC and to decrease NI. These results indicated under general conditions, CO2 can show the status of the air BAC. Increasing the ventilation and the relative humidity suitably may raise NI concentration and improve the air quality. Although the analytical results of the air quality by ANACOR and HOMALS are similar to that of chi-square test, ANACOR and HOMALS can be clearly shown in the plots with 2 or 3 axes. These two methods (ANACOR and HOMALS) may be useful to show the relationships among indoor air quality indexes more sensitively and directly

Hybrid light-emitting polymer/SiN_x platform for photonic integration

Organic semiconductors have potentials for a broad range of applications; however, it is difficult to be integrated with traditional inorganic material to meet the need of further application. Based on low-temperature silicon nitride (SiNx) deposition technique, here we demonstrate a hybrid structure fabricated by directly depositing high-quality SiNx on organic polymer film Poly[2-(2',5'-bis(2"-ethylhexyloxy)- phenyl) -1,4-phenylene vinylene] (BEHP-PPV). Stacked BEHP-PPV/SiNx hybrid structures with different periods are obtained and their optical properties are systematically characterized. Moreover, a group of BEHP/PPV embedded SiNx micro-disk is fabricated and amplification of spontaneous emission (ASE) is observed under optical pumping, further confirming that the gain properties of BEHP/PPV are well preserved. Our technique offers a platform to fabricate organic/inorganic hybrid optical devices compatible with integrated components.Comment: 6 pages, 4 figure

High expression of trimethylated histone H3 at lysine 27 predicts better prognosis in non-small cell lung cancer

Epigenetic parameters such as DNA methylation and histone modifications play pivotal roles in carcinogenesis. Global histone modification patterns have been implicated as possible predictors of cancer recurrence and prognoses in a great variety of tumor entities. Our study was designed to evaluate the association among trimethylated histone H3 at lysine 27 (H3K27me3), clinicopathological variables and outcome in early-stage non-small cell lung cancer (NSCLC). The expression of H3K27me3 and its methyltransferase, enhancer of zeste homolog 2 (EZH2) together with proliferating cell nuclear antigen (PCNA) were evaluated by immunohistochemistry in normal lung tissue (n=5) and resected NSCLC patients (n=42). In addition, the specificity of antibody for H3K27me3 was tested by western blot analysis. The optimal cut-off point of H3K27me3 expression for prognosis was determined by the X-tile program. The prognostic significance was determined by means of Kaplan-Meier survival estimates and log-rank tests. As a result, enhanced trimethylation of H3K27me3 was correlated with longer overall survival (OS) and better prognosis (P<0.05). Moreover, both univariate and multivariate analyses indicated that H3K27me3 level was a significant and independent predictor of better survival (hazard ratio, 0.187; 95% confidence interval, 0.066-0.531, P=0.002). Furthermore, H3K27me3 expression was positively correlated with DNA methylation level at CCGG sites while reversely related to EZH2 expression (P<0.05). In conclusion, H3K27me3 level defines unrecognized subgroups of NSCLC patients with distinct epigenetic phenotype and clinical outcome, and can probably be used as a novel predictor for better prognosis in NSCLC patients

Photodegradation of Trace Trichloronitromethane in Water under UV Irradiation

This study’s objective was to study the photodegradation of TCNM (trichloronitromethane) in water under UV light. The effects of light intensity, nitrate ions, chloride ions, humic acid, and pH on the photochemical degradation of TCNM were investigated under the irradiation of low pressure mercury lamp (λ = 254 nm, 12 W). The photodegradation rate of TCNM was found to increase with increasing the concentration of nitrate ions, chloride ions, humic acid, pH, and light intensity. The photodegradation of TCNM was examined at pH 6.0 with initial concentrations (C0) of TCNM at 10.0–200.0 µg/L. The overall rate of degradation of TCNM was modeled using a pseudofirst-order rate law. Finally, the proposed mechanism involved in the photodegradation of TCNM was also discussed by analysis. Results of this study can contribute to the development of new source control strategies for minimization of TCNM risk at drinking water and wastewater utilities

Design and Properties of Coal Gangue-Based Geopolymer Mortar

The feasibility of preparing coal gangue-based geopolymer mortar (CGBGM) with composite-activated coal gangue was experimentally explored in this paper. The effects of water-to-binder ratio (W/B), alkali content (A), and slag content (S) on the fluidity and performances of the CGBGM were experimentally investigated. The ANOVA method was employed to evaluate the significance level of influenced factors. Moreover, the microstructure, element compositions, and qualitative microanalysis of the CGBGM at various curing ages were verified by ESEM-EDS. Test results denoted that the mechanical properties of the CGBGM are superior to that of ordinary Portland cement mortar (OPCM). The flexural and compressive strength of the CGBGM rapidly increases before 7 d and then tends to slow afterward. According to the impact degree on the flexural and compressive strength of the CGBGM, the S is ranked first, followed by the A, and finally the W/B. The flexural and compressive strength of specimens with 40% slag increased by 45.97% and 90.75%, respectively, compared to the control group. However, the A and W/B have little effect on flexural strength. In addition, the hydration productions filled in the crevice and healed the entrapped microcracks in the hardened paste with the increase in curing ages, forming a dense microstructure. The Ca/Si decreased from 0.5 at 3 d to 0.06 at 28 d, and the Ca/Al decreased from 0.25 at 3 d to 0.05 at 28 d. Finally, the difference in drying shrinkage behavior between the CGBGM and OPCM was systematically analyzed