广东省大学生体质因子结构的研究

采用因子分析法 ,对 1991、 1995年测得的广东省大学生体质指标[1] 数据进行研究。结果表明 :大学生体质因子由体形、身体素质、视力、身高、血压、柔韧、脉搏等因子构成 ;城、乡、男、女大学生各体质因子的贡献率基本相同 ;体脂对体质影响比较大。

载肿瘤坏死因子相关凋亡诱导配体质粒聚阳离子纳米复合物的制备及体外抗肝癌活性

目的:采用新型聚阳离子载体压缩肿瘤坏死因子相关凋亡诱导配体质粒(plasmid of tumor necrosis factor related apoptosis-inducing ligand,pTRAIL),解决基因药物难以入胞、容易降解的问题,并考察其体外抗肝癌活性。方法:用纳米粒度电位测定仪测定纳米复合物的粒径及电位,琼脂糖凝胶电泳考察硬脂酰多肽(SHR)及硬脂酰多肽聚合物(SHRss)压缩pTRAIL的能力;用激光共聚焦显微镜观察肝癌细胞对SHR/pTRAIL和SHRss/pTRAIL的摄取能力;用CCK-8法检测载体的细胞毒作用及纳米复合物抗肝癌细胞增殖活性。结果:SHR和SHRss具有生物相容性,可以压缩pTRAIL,形成稳定的纳米复合物SHR/pTRAIL和SHRss/pTRAIL。N/P=10时,两种纳米复合物的粒径最小,分别为(306.22±31.64)和(184.41±25.16)nm。交联后的SHRss能够显著增强SHR压缩pTRAIL的能力,增加肝癌细胞的摄取,提高pTRAIL的药效。SHR/pTRAIL和SHRss/pTRAIL分别与HepG2细胞共孵育24h后,细胞存活率分别为(82.58±9.46)%和(65.39±5.43)%。结论:低毒、高效的SHRss/pTRAIL有可能成为一种新型的基因转运复合物用于治疗肝癌。

华南、华北地区大学生体质状况比较

增强学生体质、增进学生健康是高等学校体育教学的重要任务之一.了解掌握学生当前体质状况,可为普通高校体育课程建设提供依据和参考,也是培养跨世纪高素质人才的需要.继1985年和1991年两次大规模的全国体质调研之后,1995年国家教委又组织进行了第三次全国学生体质普查工作,获得大量的第一手资料.我国幅员辽阔,不同地区之间在气候环境、文化传统上存在较大差异,因此在体育课程的设置,教材的选编等方面均有其不同的特点.

Double Covalency Factors and DoubleξModel in Study on Optical and Magnetic Properties of Diluted Magnetic Semiconductors ZnX∶Co~ 2+

The optical absorption spectra of the covalent crystals ZnX(X=S,Se) doped with Co 2+ are studied using the double covalency factors,which considers the anisotropic distortion of e g and t 2g orbits for d electron.When the paramagnetic g factor is calculated,the contributions of the spin orbit coupling from the ligand ions are taken into account besides that from the central ion,which is the double ξ model.The calculated results indicate that the theoretical values coincide with the experimental values very well.This suggests that the method presented in this paper could be more valid to some strongly covalent crystals.

人Arresten基因真核表达质粒的构建

目的构建人Arresten基因的真核表达质粒。方法设计人Arresten基因引物序列,取100 mg新鲜的胎盘组织提取总RNA,采用RT-PCR法扩增Arresten基因。将获取的Arresten基因片段和p IRES2-EGFP质粒分别用Bam HⅠ和EcoRⅠ作双酶切,将酶切产物与质粒连接,转化感受态大肠杆菌DH-5α进行真核表达。采用酶切、菌液PCR及测序的方法检测Arresten基因真核表达质粒构建的正确性。结果经双酶切鉴定,得到1条约700 bp的片段和1条与p IRES2-EGFP空载体(5.3 kb)相近的片段,符合Arresten基因重组质粒大小。经重组质粒的菌液PCR鉴定,7组菌液均扩增出700 bp大小的扩增片段,均为阳性克隆。测序结果示,Arresten基因mRNA与GenBank中人Arresten序列完全一致。结论成功构建了人Arresten基因的真核表达质粒。

Effects of quasi-periodicity on defect modes of photonic crystals

In this letter,the effects of Bragg-mirror quasi-periodicity on the shifts and quality factor in defect modes of photonic crystals are studied by using the transfer matrix method.Furthermore the influence of the quasi-periodicity on electric field enhancement effect inside the defect layer is studied,which is similar to that on the quality factor.

Evaluation of malignancy using Ki-67,p53,EGFR and COX-2 expressions in gastrointestinal stromal tumors

AIM:To investigate the role of expressions of Ki-67, p53,epidermal growth factor receptor(EGFR)and cyclooxygenase-2(COX-2)in gastrointestinal stromal tumor(GIST)grading and prognosis. METHODS:Tumor tissue was collected retrospectively from 96 patients with GIST.Antibodies against Ki-67, p53,EGFR and COX-2 were used for immunohistochemical staining.Tumor grading was designated according to a consensus system and the staining was quantified in 3 categories for each antibody in the statistical analysis. RESULTS:The Ki-67 expression in GISTs was significantly associated with the size of the tumors,mitotic rate and the risk of malignancy(x2=15.51,P=0.02; x2=22.27,P<0.001;x2=20.05;P<0.001).The p53 expression was also significantly correlated with mitotic rate and the risk of malignancy(x2=9.92,P= 0.04;x2=9.97;P=0.04).Over-expression of Ki-67 was strongly correlated with poor survival(x2=10.44, P=0.006),but no correlation was found between the expression of p53,EGFR or COX-2 and survival. Multivariate analysis further demonstrated that Ki-67 expression(relative risk=15.78,95%CI:4.25-59.37) could be used as an independent prognostic value for GIST patients.Adjuvant imatinib therapy could improve clinical outcomes in the patients with high risk and intermediate risk of recurrence after complete tumor resections(median survival time:52 mo vs 37 mo, x2=7.618,P=0.006). CONCLUSION:Our results indicated that the expression of Ki-67 could be used as an independent prognostic factor for GIST patients.

Theoretical basis of a beneficial role for vitamin D in viral hepatitis

Abnormal bone metabolism and dysfunction of the calcium-parathyroid hormone-vitamin D axis have been reported in patients with viral hepatitis. Some studies suggested a relationship between vitamin D and viral hepatitis. Genetic studies have provided an opportunity to identify the proteins that link vitamin D to the pathology of viral hepatitis (i.e., the major histocompatibility complex class Ⅱ molecules, the vitamin D receptor, cytochrome P 450 , the renin-angiotensin system, apolipoprotein E, liver X receptor, toll-like receptor, and the proteins regulated by the Sp1 promoter gene). Vitamin D also exerts its effects on viral hepatitis via non-genomic factors, i.e., matrix metalloproteinase, endothelial vascular growth factor, prostaglandins, cyclooxygenase-2, and oxidative stress. In conclusion, vitamin D could have a beneficial role in viral hepatitis. Calcitriol is best used for viral hepatitis because it is the active form of the vitamin D 3 metabolite.

Accommodating the bacterial decoding release factor as an alien protein among the RNAs at the active site of the ribosome

The decoding release factor （RF） triggers termination of protein synthesis by functionally mimicking a tRNA to span the decoding centre and the peptidyl transferase centre （PTC） of the ribosome. Structurally, it must fit into a site crafted for a tRNA and surrounded by five other RNAs, namely the adjacent peptidyl tRNA carrying the completed polypeptide, the mRNA and the three rRNAs. This is achieved by extending a structural domain from the body of the protein that results in a critical conformational change allowing it to contact the PTC. A structural model of the bacterial termination complex with the accommodated RF shows that it makes close contact with the first, second and third bases of the stop codon in the mRNA with two separate loops of structure＂ the anticodon loop and the loop at the tip of helix orS. The anticodon loop also makes contact with the base following the stop codon that is known to strongly influence termination efficiency. It confirms the close contact of domain 3 of the protein with the key RNA structures of the PTC. The mRNA signal for termination includes sequences upstream as well as downstream of the stop codon, and this may reflect structural restrictions for specific combinations of tRNA and RF to be bound onto the ribosome together. An unbiased SELEX approach has been investigated as a tool to identify potential rRNA-binding contacts of the bacterial RF in its different binding conformations within the active centre of the ribosome.

Cellular and molecular mechanisms of intestinal fibrosis

Fibrosis is a chronic and progressive process characterized by an excessive accumulation of extracellular matrix (ECM) leading to stiffening and/or scarring of the involved tissue. Intestinal fibrosis may develop in several different enteropathies, including inflammatory bowel disease. It develops through complex cell, extracellular matrix, cytokine and growth factor interactions. Distinct cell types are involved in intestinal fibrosis, such as resident mesenchymal cells (fibroblasts, myofibroblasts and smooth muscle cells) but also ECM-producing cells derived from epithelial and endothelial cells (through a process termed epithelialand endothelial-mesenchymal transition), stellate cells, pericytes, local or bone marrow-derived stem cells. The most important soluble factors that regulate the activation of these cells include cytokines, chemokines, growth factors, components of the renin-angiotensin system, angiogenic factors, peroxisome proliferator-activated receptors, mammalian target of rapamycin, and products of oxidative stress. It soon becomes clear that although inflammation is responsible for triggering the onset of the fibrotic proc-ess, it only plays a minor role in the progression of this condition, as fibrosis may advance in a self-perpetuating fashion. Definition of the cellular and molecular mechanisms involved in intestinal fibrosis may provide the key to developing new therapeutic approaches.

ERK1/2 contributes negative regulation to STAT3 activity in HSS-transfected HepG2 cells

Signal transducer and activator of transcription 3 (STAT3) is a recently characterized transcription factor which is essential to liver regeneration. We have previously reported that hepatic stimulator substance (HSS), a novel growthpromoting substance, phosphorylated the epidermal growth factor (EGF) receptors and activated downstream RasMAP kinase (extracellular signal-regulated kinases, ERK1/2) cascade. However, whether HSS signal is related to STAT3pathway remains unclear. The present study is aiming to explore the regulatory effect of activation of ERK1/2 evoked by HSS on STAT3 phosphorylation and STAT3 signaling. Human hepatoma cell line HepG2 was stably transfected with HSS cDNA and HSS expression was measured by Northern blot. The results showed that the transfection of HSS into HepG2 resulted in remarkable increase in cellular proliferation as compared with the non-transfected cells, and it was further proved that the cellular proliferation in the HSS-transfected cells was related to ERK1/2 activation. Treatment of the cells with 50 μM of PD98059, an ERK1/2 specific upstream inhibitor, resulted in ERK1/2 inactivation completely.Inhibition of ERK1/2 allowed the tyrosine of STAT3 to be phosphorylated in a dose-dependent manner to PD98059.Furthermore, transient transfection of STAT3 mutant (STAT3S727A) into HSS-bearing cells could remarkably reverse the inhibitory effect of ERK1/2 on STAT3 phosphorylation. Based upon these results, it is concluded that ERK1/2negatively modulates STAT3 phosphorylation and this function is dependent on residual serine-727 (S727) of STAT3.

PEG－mediated Gene Transfer into Orychophragmus Violaceus Cotyledon Protoplast and Regeneration of Transgenic Plants

Transgenic plants were obtained by PEG-mediated tranfer of foreign gene into cotyledon protoplasts of Orychophragums violaceus. Systematic study was carricd out on PEG-mediatcd transformation of cotyledon protoplast using transient expression system, which showed 25-30 μg of pasmid, 15% PEG and a pH value of 8.0 as the optimal parameters contributing to the highest expression level. Using these parameters, cotyledon protoplasts were isolated, treated with bacterial plasmid DNA (pBI222 with HPT as selective marker) and PEG, and cultured at a density of 5×10 4/ml.After 10-15 days,they were selected by adding 25 μg/ml hygromycine. One month later, a few calli were observed, which were then transferred onto a solid medium with 50-100 μg/ml hygromycine for proliferation. Later they were transferred successively onto differentiation and rooting media and finally hygromycineresistant whole plants were obtaincd. The plants grew well in pots and a regeneration rate of 5 ×10(-5) was achieved. Then,excised leaves of the transgenic plants were used as explants for Southern blot analysis, which confirmed the stable integration of HPT gene into the chromosomal genome of Orychophragmus violaceus The transformation frequency was 10-5.

Epidermal growth factor receptor:a key manipulator in molecular pathways of malignant glioma

The epidermal growth factor receptor （EGFR） is a member of the ErbB/EGFR family, including EGFR/Herl, ErbB2/Her2, ErbB-3/Her3, and ErbB-4/Her4. EGFR exerts its effects through the receptor tyrosine kinase phosphorylation and activation of important downstream signaling pathways in normal and neoplastic cells, mainly the Ras GTPase/MAP kinase （MAPK）, STAT3, and phosphatidylinositide 3 kinase-AKT pathways. EGFR deregulation is common in malignant glioma, especially primary glioblastoma, and exists in three forms： gene overexpression （amplification）, autocrine effects of EGFR activation, and activating receptor mutation （EGFRvlII）. However, some EGFR abnormalities have also been found in low-grade gliomas, including the nuclear localization of EGFR, expression in the microfoci of anaplastic transformation, and association with neovascularization in the mesenchyma of the glioma, which suggests that some unknown EGFR-related mechanisms are possibly responsible for its central role in the initiation and progression of malignant glioma. Uncovering these mechanisms will have potential value in the development of radio- therapy, chemotherapy, and EGFR-targeted therapy for glioma.

hVEGF165 Expression in Escherichia coli Conserves Its Biological Function

The paper describes the expression of human protein VEGF165 in Escherichia coli and its purification. This growth factor isoform contains exon 7, which is essential for binding to extracellular domain of VEGF receptor 2, located on endothelial cells lining the surface of blood vessels. This binding stimulates the cascade of downstream signalling events leading to process known as angiogenesis, hVEGF165 overexpressed with His-tag in BL21 E. coli cells forms inclusion bodies （insoluble protein）, so the research found the procedure for its solubilization and purification on a Nickel based affinity chromatography. Although this eukaryotic signal protein needs posttranslational processing for its full function as a homodimer, author verified the biological activity of our hVEGF165 protein, obtained as monomer, by wound healing test.

In vitro effect of p2l^(WAF-1/CIP1) gene on growth of human glioma cells mediated by EGFR targeted non-viral vector GE7 system

Objective: To construct the EGFR targeted non-viral vector GE7 system and explore the in vitro effect of p21WAF-1/CIPI gene on growth of human glioma cells mediated by the GE7 system. Methods: The EGFR targeted non-viral vector GE7 gene delivery system was constructed. The malignant human glioma cell line U251MG was transfected in vitro with β-galactosidase gene ( reporter gene) and p21WAF-1/CIPI gee (therapeutic gene) using the GE7 system. By means of X-gal staining, MTS and FACS, the transfection efficiency of exogenous gene and apoptosis rate of tumor cells were examined. The expression of p21WAF-1/ CIPI gene in transfected U251MG cell was examined by immunohistochemis-try staining. Results: The highest transfer rate of exogenous gene was 70% . After transfection with p21WAF-1/CIPI gene, the expression of WAF-1 increased remarkably and steadily; the growth of U251MG cells were inhibited evidently. FACS examination showed G1 arrest. The average apoptosis rate was 25.2%. Conclusion: GE7 system has the ability to transfer exogenous gene to targeted cells efficiently, and expression of p21WAF-1/CIPI gene can induce apoptosis of glioma cell and inhibit its growth.

Effect of substance P on gene expression of transforming growth factor β-1 and its receptors in rat's fibroblasts

Objective: To investigate the effect of substance P (SP) on gene expression of transforming growth factor β-1 (TGFβ-1), transforming growth factor receptor-1 (TGFR-1) and transforming growth factor receptor-2 (TGFR-2) in fibroblasts cultured in vitro from rat’s granulation tissues. Methods: The fibroblasts from the granulation tissues in the skeletal muscle of rat’s hind limbs injured by formaldehyde were cultured in vitro. When different concentrations (10 -9-10 -5 mol/L) of SP were added into the culture medium, the changes of gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the cultured fibroblasts were observed with reverse transcription polymerase chain reaction at different intervals (0, 3, 6, 12 and 24 hours after incubation). Results: The gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the fibroblasts cultured from rat’s granulation tissues was up-regulated by SP. The peak level of the mRNA expression was found at 10 -8 mol/L SP and the up-regulation effect was not found at 10 -5 mol/L and 10 -6 mol/L. The peak levels of gene expression of TGFβ-1, TGFR-1 and TGFR-2 in the fibroblasts treated with SP were achieved at 6 and 12 hours, respectively. Conclusions: SP has up-regulation effect on the gene expression of TGFβ-1, TGFR-1 and TGFR-2 in fibroblasts from rat’s granulation tissues in vitro, and the effect is related to different stimulating concentrations of SP. It may be concerned with proliferation and differentiation of fibroblasts and formation of scar tissues during wound healing.

Distribution, occurrence and enrichment causes of gallium in coals from the Jungar Coalfield, Inner Mongolia

We collected eleven bench samples of No. 6 coal from the Heidaigou Surface Mine, Jungar Coalfield, Inner Mongolia, China, and four samples from the affiliated coal preparation plant. Based on these samples, we used inductively coupled-plasma mass spectroscopy, X-ray diffraction, scanning electron microscope with an energy-dispersive X-ray spectrometer techniques, and borehole exploration data, to investigate the distribution, occurrence and enrichment causes of gallium （Ga） in the coals. Our results show： （1） Gallium is significantly enriched in the coal seams from the study area, with an average content of 18.8-26.0 ppm. Gallium is distributed heterogeneously in the coals, and reaches ore-forming scales only in No. 6 coal of Heidaigou Surface Mine, not in the other mining districts of Jungar Coalfield. （2） On the horizontal plane, Ga is enriched in the main minable coals from the northern and middle part of the coalfield. In the vertical profile, Ga content in the coal seams is higher at the base of Taiyuan Formation （Nos. 8 and 9） and Shanxi Formation （Nos. 3 and 4） than at the top of the Taiyuan Formation. Within the identical coal seam, Ga content is higher in the benches near the roof and floor than in the middle section. （3） Gallium in the coals is associated mainly with kaolinite and boehmite. Additionally, Ga may be adsorbed to some extent by humic acid, resulting in a high level in weathering coal. （4） Geological factors affect Ga enrichment in coal, such as the prop- erty of parent rocks in the source area, the sedimentary environment, organic matter, structure, and past magmatic hydrothermal activity. Especially, Ga content in parent rocks plays a leading role. （5） The mobility and precipitation of trace elements like Ga are controlled principally by the geochemical behavior of the major element A1. Terrestrial and transgressive environments can cause the precipitation of bauxite, whereas marine-continental depositional environments may cause the separation of Ga from A1. In addition, Ga may migrate in the form of gas tively enriched in high-volatile coal. and may be affected by the ground temperature. Thus, it is relatively enriched in high-volatile coal.

A high quality factor photonic crystal channel-drop filter with a linear gradient microcavity

We design a channel-drop filter(CDF)with a linear gradient microcavity in a two-dimensional(2D)photonic crystal(PC).The model of three-port CDF with reflector is used to achieve high quality factor(Q-factor)and 100%channel-drop efficiency.The research indicates that adjusting the distance between reference plane and reflector can simultaneously influence the Q-factor due to coupling to a bus waveguide and the phase retardation occurring in the round trip between a microcavity and a reflector.The calculation results of 2D finite-difference time-domain(FDTD)method show that the designed filter can achieve the drop efficiency of 96.7%and ultra-high Q-factor with an ultra-small modal volume.

Effect of acupuncture on serum PYY and nesfatin-1 in obese patients with insulin resistance

Objective To observe the effect of acupuncture on serum peptide YY(PYY)and nesfatin-1 in obese patients with insulin resistance.Methods Ninety-eight obese patients with insulin resistance were divided into a control group and an observation group by the random number table method,with 49 cases in each group.The control group received exercise and dietary interventions,and the observation group received additional acupuncture treatment to the exercise and dietary interventions.The body mass index(BMI),body fat percentage,fasting insulin(FINS),fasting plasma glucose(FPG),homeostasis model assessment for insulin resistance(HOMA-IR),triglyceride(TG),total cholesterol(TC),and serum PYY and nesfatin-1 levels were compared before and after treatment.The efficacy was evaluated after treatment.Results The total effective rate was significantly higher in the observation group than in the control group(P<0.05).After treatment,the BMI,body fat percentage,and serum TG and TC levels decreased significantly in both groups(P<0.05),and were significantly lower in the observation group than those in the control group(P<0.05).The FINS,FPG,HOMA-IR,and serum PYY and nesfatin-1 levels of the control group were not significantly changed after treatment(P>0.05).The FINS,FPG and HOMA-IR of the observation group decreased significantly after treatment(P<0.05),and were lower than those in the control group(P<0.05).The serum PYY and nesfatin-1 levels of the observation group increased significantly after treatment(P<0.05),and were higher than those in the control group(P<0.05).Conclusion Based on exercise and dietary interventions,acupuncture is effective for obese patients with insulin resistance.It can reduce the BMI,body fat percentage,blood lipids,blood glucose,and serum insulin levels and improve insulin resistance.The action may be associated with the up-regulation of serum PYY and nesfatin-1.

Effect of moxibustion on CRF and CRFR1 expressions in hypothalamus of TNBS-induced experimental colitis rats

Objective： To observe the effect of moxibustion on the protein and mRNA expressions of corticotropin-releasing factor （CRF） and corticotropin-releasing factor receptor 2 （CRFR1） in hypothalamus of trinitrobenzene sulfonic acid （TNBS）-induced experimental colitis rats, and to explore the central mechanisms of moxibustion in improving visceral pain and the pain-related emotions in experimental colitis rats. Methods： Thirty-six Sprague-Dawley （SD） rats were randomly divided into a normal group （NG）, a model group （MG）, a herb-partitioned moxibustion group （HPMG） and a sham herb-partitioned moxibustion group （SHPMG）. Except the NG, rats in the remaining three groups all received TNBS enema to establish experimental colitis models. The HPMG received herb-partitioned moxibustion （HPM） at bilateral Tianshu （ST 25） and Qihai （CV 6） for intervention; for the SHPMG, the herbal cakes and moxa cones were only placed on the acupoints but not ignited; rats in the MG and NG were only fixed in the same way as those in the HPMG but did not receive any treatment. At the end of the intervention, the abdominal withdrawal reflex （AWR） score, the open field test （OFT） score and the elevated plus maze （EPM） score were observed to measure the changes in visceral pain and pain-related emotions of the rats. The enzyme-linked immunosorbent assay （ELISA） was used to examine the expressions of CRF and CRFR1 proteins in hypothalamus; the fluorescence-based quantitative polymerase chain reaction （PCR） was used to detect the expressions of CRF and CRFR1 mRNAs in hypothalamus. Results： Compared with the NG, the AWR score increased significantly and the OFT and EPM scores dropped significantly in the MG （all P〈0.05）, and the expressions of hypothalamic CRF and CRFR1 proteins and mRNAs increased significantly （all P〈0.01）. Compared with the MG and SHPMG, the AWR score dropped significantly and the OFT and EPM scores increased significantly in the HPMG （all P〈0.01）, and the expressions of hypothalamic CRF and CRFRI proteins and mRNAs decreased significantly （all P〈0.05）. There were no significant differences between the MG and the SHPMG （all P〉0.05）. Conclusion： HPM can down-regulate the abnormally increased expressions of CRF and CRFR1 proteins and mRNAs in hypothalamus of the TNBS-induced experimental colitis rats, which is plausibly one of its action mechanisms in mitigating visceral pain and the pain-related emotions in the experimental colitis rats.