The p38 MAPK and NF-κB Pathways are Involved in Cyclic Compressive Force-induced IL-6 Secretion in MLO-Y4 Cells

ABSTRACT We previously revealed the involvement of extracellular regulated protein kinases 1/2 (ERK1/2) in interleukin-6 (IL-6) secretion induced by cyclic compressive force (CCF) in MLO-Y4 cells. In this study, we investigated the contributions of the p38 mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways to IL-6 secretion by stimulating MLO-Y4 cells with CCF. At 80% confluence, different magnitudes (1000μstrain, 2000 μstrain and 4000 μstrain), frequencies (0.5 Hz, 1.0 Hz and 2.0 Hz) and durations (10 min, 30 min, 1 h, 3 h and 6 h) of CCF were loaded onto cells using a four-point bending system. Flow Cytometry (FCM) analysis was used to analyze cell mortality rates after CCF loading. p38 and p65 phosphorylation as well as IκBα degradation in MLO-Y4 cells were detected by Western blotting (WB). Changes in IL-6 secretion after inhibitor treatment were assessed by enzyme-linked immunosorbent assays (ELISAs). Cellular viability was over 90 percent after CCF. p38 and p65 phosphorylation increased under all conditions, whereas IκBα protein levels decreased. However, phosphorylation and degradation were not completely dependent on the loading magnitude, frequency or duration. Furthermore, p38 inhibition using the specific inhibitor SB203580 reduced both p38 phosphorylation and IL-6 secretion. Similarly, NF-κB inhibition using BAY 11-7082 decreased p65 phosphorylation and IL-6 secretion but increased the concentration of IκBα. These findings reveal significant roles for the p38 and NF-κB signaling pathways in IL-6 secretion induced by CCF in MLO-Y4 cells.

Study on expression of Syntaxin 8 protein in gastric carcinoma / 中国现代普通外科进展

Objective:To determine the expression of syntaxin 8 in gastric carcinoma and its clinical significance.Methods:To determine the expression levels of syntaxin 8 in gastric carcinoma and pericancerous stomach tissues of 62 patients with gastric carcinoma by immunohistochemistry,western blot.Results:Results of immunohistochemistry and western blot showed that the expression of syntaxin 8 was significantly higher than that in the adjacent pericancerous stomach tissues,and syntaxin 8 is negative in most normal tissues.The difference was statistically significant (P＜0.05).Correlation analysis found that the high expression of syntaxin 8 in gastric carcinoma tissue was not significantly related to gender,age,tumor size,TNM stage,invasion and metastasis of gastric carcinoma,but the higher expression rate was up-regulated in gastric carcinoma with distant metastasis.Conclusion:Syntaxin 8 is abnormal high expression in gastric carcinoma tissues,and is related to the occurrence and development of gastric carcinoma.It may also be a potential target for gastric carcinoma diagnosis and treatment.

Activation of Nrf2 by 18α-GA affects proliferation of adult neural stem cells / 中国病理生理杂志

AIM:To investigate the effect of nuclear factor E2-related factor 2 (Nrf2) activation by 18α-gly-cyrrhetinic acid (18α-GA) on the proliferation and self-renewal of adult neural stem cells (aNSCs), and to explore an ef-fective way of maintaining the viability of aNSCs .METHODS:NSCs were dissociated from subventricular zone of the mice at postnatal days 0, 60, and 300.The expression levels of Nrf2 in the NSCs at various ages were compared .After treatment with 18α-GA, the expression of Nrf2 was examined by real-time PCR and Western blot.shRNA lentiviral vector (LV) car-rying green fluorescent protein (GFP) gene was constructed to knock down Nrf2 expression.The knockdown efficiency in the aNSCs was detected by real-time PCR and Western blot .Subsequently , the aNSCs were divided into DMSO group , 18α-GA group, LV-GFP group and LV-Nrf2-shRNA group.BrdU incorporation assay , Tuj1 staining, CCK-8 assay, Hoechst 33342/PI staining and detection of reactive oxygen species ( ROS) were performed to analyze the proliferation , dif-ferentiation, viability, apoptosis and oxidative stress levels of the NSCs .RESULTS:The mRNA expression level of Nrf2 in adult and aged NSCs was significantly lower than that in newborn NSCs (P<0.01), while the ROS level of aNSCs was significantly higher (P<0.05).After treatment with 18α-GA, the expression level of Nrf2 in the aNSCs was significantly up-regulated as compared with DMSO group ( P<0.01).Increased number of BrdU +and Tuj1 +cells was observed in 18α-GA group, indicating that 18α-GA-treated cells had higher viability (P<0.05).Meanwhile, there were fewer apop-totic cells and lower ROS level in 18α-GA group than those in DMSO group (P<0.05).After knockdown of Nrf2 in aNSCs and then treated with 18α-GA, there were less BrdU +and Tuj1 +cells, as well as the aNSCs with lower viability in LV-Nrf2-shRNA group (P<0.05).Moreover, the ROS level was increased in LV-Nrf2-shRNA group as compared with LV-GFP group (P<0.05).CONCLUSION:Activation of Nrf2 by 18α-GA elevates the antioxidant capacity of aNSCs , thus ameliorating the cell proliferation and differentiation potentials .

Study on expression of Syntaxin 8 protein in gastric carcinoma / 中国现代普通外科进展

Objective:To determine the expression of syntaxin 8 in gastric carcinoma and its clinical significance.Methods:To determine the expression levels of syntaxin 8 in gastric carcinoma and pericancerous stomach tissues of 62 patients with gastric carcinoma by immunohistochemistry,western blot.Results:Results of immunohistochemistry and western blot showed that the expression of syntaxin 8 was significantly higher than that in the adjacent pericancerous stomach tissues,and syntaxin 8 is negative in most normal tissues.The difference was statistically significant (P＜0.05).Correlation analysis found that the high expression of syntaxin 8 in gastric carcinoma tissue was not significantly related to gender,age,tumor size,TNM stage,invasion and metastasis of gastric carcinoma,but the higher expression rate was up-regulated in gastric carcinoma with distant metastasis.Conclusion:Syntaxin 8 is abnormal high expression in gastric carcinoma tissues,and is related to the occurrence and development of gastric carcinoma.It may also be a potential target for gastric carcinoma diagnosis and treatment.

Activation of Nrf2 by 18α-GA affects proliferation of adult neural stem cells / 中国病理生理杂志

AIM:To investigate the effect of nuclear factor E2-related factor 2 (Nrf2) activation by 18α-gly-cyrrhetinic acid (18α-GA) on the proliferation and self-renewal of adult neural stem cells (aNSCs), and to explore an ef-fective way of maintaining the viability of aNSCs .METHODS:NSCs were dissociated from subventricular zone of the mice at postnatal days 0, 60, and 300.The expression levels of Nrf2 in the NSCs at various ages were compared .After treatment with 18α-GA, the expression of Nrf2 was examined by real-time PCR and Western blot.shRNA lentiviral vector (LV) car-rying green fluorescent protein (GFP) gene was constructed to knock down Nrf2 expression.The knockdown efficiency in the aNSCs was detected by real-time PCR and Western blot .Subsequently , the aNSCs were divided into DMSO group , 18α-GA group, LV-GFP group and LV-Nrf2-shRNA group.BrdU incorporation assay , Tuj1 staining, CCK-8 assay, Hoechst 33342/PI staining and detection of reactive oxygen species ( ROS) were performed to analyze the proliferation , dif-ferentiation, viability, apoptosis and oxidative stress levels of the NSCs .RESULTS:The mRNA expression level of Nrf2 in adult and aged NSCs was significantly lower than that in newborn NSCs (P<0.01), while the ROS level of aNSCs was significantly higher (P<0.05).After treatment with 18α-GA, the expression level of Nrf2 in the aNSCs was significantly up-regulated as compared with DMSO group ( P<0.01).Increased number of BrdU +and Tuj1 +cells was observed in 18α-GA group, indicating that 18α-GA-treated cells had higher viability (P<0.05).Meanwhile, there were fewer apop-totic cells and lower ROS level in 18α-GA group than those in DMSO group (P<0.05).After knockdown of Nrf2 in aNSCs and then treated with 18α-GA, there were less BrdU +and Tuj1 +cells, as well as the aNSCs with lower viability in LV-Nrf2-shRNA group (P<0.05).Moreover, the ROS level was increased in LV-Nrf2-shRNA group as compared with LV-GFP group (P<0.05).CONCLUSION:Activation of Nrf2 by 18α-GA elevates the antioxidant capacity of aNSCs , thus ameliorating the cell proliferation and differentiation potentials .

High Glucose Causes Human Cardiac Progenitor Cell Dysfunction by Promoting Mitochondrial Fission: Role of a GLUT1 Blocker

Cardiovascular disease is the most common cause of death in diabetic patients. Hyperglycemia is the primary characteristic of diabetes and is associated with many complications. The role of hyperglycemia in the dysfunction of human cardiac progenitor cells that can regenerate damaged cardiac tissue has been investigated, but the exact mechanism underlying this association is not clear. Thus, we examined whether hyperglycemia could regulate mitochondrial dynamics and lead to cardiac progenitor cell dysfunction, and whether blocking glucose uptake could rescue this dysfunction. High glucose in cardiac progenitor cells results in reduced cell viability and decreased expression of cell cycle-related molecules, including CDK2 and cyclin E. A tube formation assay revealed that hyperglycemia led to a significant decrease in the tube-forming ability of cardiac progenitor cells. Fluorescent labeling of cardiac progenitor cell mitochondria revealed that hyperglycemia alters mitochondrial dynamics and increases expression of fission-related proteins, including Fis1 and Drp1. Moreover, we showed that specific blockage of GLUT1 improved cell viability, tube formation, and regulation of mitochondrial dynamics in cardiac progenitor cells. To our knowledge, this study is the first to demonstrate that high glucose leads to cardiac progenitor cell dysfunction through an increase in mitochondrial fission, and that a GLUT1 blocker can rescue cardiac progenitor cell dysfunction and downregulation of mitochondrial fission. Combined therapy with cardiac progenitor cells and a GLUT1 blocker may provide a novel strategy for cardiac progenitor cell therapy in cardiovascular disease patients with diabetes.

Discussing of influence mechanism of Chinese herbal monomer on physical stability of cream / 中国中药杂志

This study left flavonoids and alkaloids Chinese herbal monomer with common parent nucleus as cream base carriages drug respectively, cream base were prepared with stable span 60-tween 80 emulsification system. The near-infrared stability analysis technology was performed to quantitatively characterize the physical stability of cream. Base on the theory of gel network structure, theory of emulsification, theory of solubility parameter and theory of double layer, the influence mechanism of Chinese herbal monomer on physical stability of cream was discussed. The results showed that tetrahydropalmatine, matrine and naringenin had similar solubility parameter value with cream base material, creams prepared with those Chinese herbal monomer have higher Zeta potential value and stronger physical stability, and that those creams had similar microstructure information with cream base. However, a larger solubility parameter difference exists between baicalin, baicalein, berberine, palmatine and cream base material. Creams prepared with those Chinese herbal monomers had lower Zeta potential value and poorer physical stability, and that those creams had great different microstructure information with cream base.

Plant regeneration and Agrobacterium-mediated transformation of Achyranthes bidentata using cotton EREBP gene

The aim of this work was to study the plant regeneration and Agrobacterium-mediated transformation of Achyranthes bidentata using cotton EREBP gene. Results showed that the callus induction rate of stems from A. bidentata was the highest (100%) and bud was in approximately 70% of calli from stems. However bud differentiation rate of the callus from leaves and petioles was very low. Compared with ceftriaxone, 200mg/L cefotaxime could completely control Agrobacterium tumefaciens and had relatively less toxic action on the stems of A. bidentata. In addition, the induction rate of callus resistant to hygromycin was the highest when infected for 3 min and co-cultivated for 3 d. Six positive transgenic plants transformed with pCAMBIA1304-GhEREB2 expression vector were obtained and confirmed by PCR. The expression of target gene GhEREB2 was detected in five transgenic plants by RT-PCR. In brief, an efficient system of genetic transformation and plant regeneration was established for A. bidentata.

EsxA might as a virulence factor induce antibodies in patients with Staphylococcus aureus infection

Staphylococcus aureus (S. aureus) is an important human pathogen, which commonly causes the acquired infectious diseases in the hospital and community. Effective and simple antibiotic treatment against S. aureus-related disease becomes increasingly difficult. Developing a safe and effective vaccine against S. aureus has become one of the world's hot spots once again. The key issue of developing the vaccine of S. aureus is how to find an ideal key pathogenic gene of S. aureus. It was previously suggested that EsxA might be a very important factor in S. aureus abscess formation in mice, but clinical experimental evidence was lacking. We therefore expressed EsxA protein through prokaryotic expression system and purified EsxA protein by Ni-affinity chromatography. ELISA was used to detect the anti-EsxA antibodies in sera of 78 patients with S. aureus infection and results showed that the anti-EsxA antibodies were positive in the sera of 19 patients. We further analyzed the EsxA positive antibodies related strains by antimicrobial susceptibility assay and found that all of the corresponding strains were multi-drug resistant. Among those multi-drug resistant strains, 73.7% were resistant to MRSA. The results indicated EsxA is very important in the pathogenesis of S. aureus. We suggested that the EsxA is very valuable as vaccine candidate target antigens for prevention and control of S. aureus infection.

Effects of CYP1A1 and GSTM1 gene polymorphisms and BPDE-DNA adducts on lung cancer / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the effect of CYP1A1 and GSTM1 genetic polymorphisms and BPDE-DNA adducts on lung tumorigenesis.</p><p><b>METHODS</b>The case control study has included 200 cases of lung cancer and 200 controls. DNA was extracted from blood samples of all subjects. The genotype of both CYP1A1 and GSTM1 were detected with PCR-based restriction fragment length polymorphisms (PCR-RELP). BPDE-DNA adducts were detected with competitive ELISA.</p><p><b>RESULTS</b>CYP1A1 mutant genotype and GSTM1 null genotype with smoke has increased the risk of lung cancer, with OR being 2.406(1.321-4.382), 2.755(1.470-5.163), respectively. The level of BPDE-DNA adducts in patients was greater than control, and the adduct level in ever smokers was higher than never smokers, the difference was statistically significant (P= 0.0252). GSTM1 null genotype individuals with BPDE-DNA level higher than 5 adducts/10(8) nucleotide have increased risk of lung cancer (OR= 1.988, 95%CI: 1.011-3.912). Compared with never smokers with CYP1A1 wild genotype, smokers with CYP1A1 mutation genotype had an increased risk of forming a higher level of DNA adducts (P= 0.0459). Smokers with GSTM1 null genotype formed more DNA adducts compared with never smokers with GSTM1 functional genotype (OR = 2.432, 95% CI: 1.072-4.517).</p><p><b>CONCLUSION</b>GSTM1 null genotype with higher level DNA adducts may increase the risk of lung cancer. DNA adducts form easier in smokers with CYP1A1 mutation genotype and GSTM1 null genotype, which in turn may influence lung tumorigenesis.</p>

Correlation between RARbeta gene promoter methylation and P53 gene mutations in non-small cell lung cancer / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the correlation between RARbeta gene promoter methylation and P53 gene mutations in non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>Promoter methylation of RARbeta and P53 mutations of exons 5 through 9 in 198 resected primary NSCLC tissues were determined by methylation-specific PCR and direct sequencing.</p><p><b>RESULTS</b>RARbeta gene promoter methylation and P53 mutation were detected in 58.1% and 36.4% of tumors, respectively. Both were higher in males than in females and in smokers than in nonsmokers. A higher prevalence of RARbeta promoter methylation was found in patients with advanced stage tumors than those with TNM stage I. P53 gene mutations were more frequent in squamous cell carcinoma and adeno-squamous carcinoma than adenocarcinoma. All such differences were statistically significant (P< 0.05). Frequencies of P53 mutations, including G:C>T:A mutations, transversions and missense mutations were significantly higher in tumors with RARbeta methylation than in those without (P< 0.05). A significantly higher prevalence of RARbeta methylation was found in tumors with only G:C>T:A mutation in P53 gene than those without P53 mutations (P< 0.05). This difference (OR=3.737, 95%CI: 1.414-9.873) was still statistically significant (P< 0.05) in smokers (OR=4.020, 95%CI: 1.263-12.800), squamous cell carcinomas (OR=5.480, 95%CI: 1.400-21.446) or patients with advanced tumors (OR=3.446, 95%CI: 1.054-11.267) after adjusting for age and sex.</p><p><b>CONCLUSION</b>RARbeta methylation is associated with G:C>T:A mutations in P53 gene in NSCLC.</p>

Relationship between promoter methylation of p16, DAPK and RAR beta genes and the clinical data of non-small cell lung cancer / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the effects of promoter methylation of p16, death-associated protein kinase (DAPK) and retinoic acid receptor-beta (RAR beta) genes on clinical data in non-small cell lung cancers, and to study the effect of smoking on the risk of gene methylation.</p><p><b>METHODS</b>The promoter methylation of p16, DAPK and RAR beta genes in 200 primary non-small cell lung cancers and the corresponding nonmalignant lung tissues were determined by methylation-specific PCR.</p><p><b>RESULTS</b>Methylation in the tumor tissues was detected in 51.0% for p16, 60.0% for DAPK, and 58.0% for RAR beta gene, with significant differences (P < 0.05) when compared with those in the corresponding nonmalignant tissues(12.5%, 11.5% and 15.0%) respectively. p16 gene methylation in tumor tissue was associated with age significantly in unconditional logistic regression analysis (P < 0.01) and histologic type (P < 0.05). DAPK gene methylation in tumor tissue was associated significantly with age (P < 0.05), gender (P < 0.05) and clinical type (P < 0.05). RAR beta gene methylation in tumor tissue was associated with clinical type (P < 0.05) and tumor stage (P < 0.05) significantly. The interaction odds ratio (OR) for the gene-gene interaction in tumor tissue between p16 and DAPK was 1.987 (95%CI:1.055-3.743). The results of the gene-smoking analyses revealed that a relationship existed between cigarette smoking and p16 gene methylation (OR = 3.139, 95%CI: 1.046-9.419), the OR for the relationship of DAPK gene methylation and cigarette smoking was 3.585(95%CI: 1.270-10.123) in tumor tissue. The RAR beta gene methylation did not differ based on the smoking status of patients in tumor tissue.</p><p><b>CONCLUSION</b>The p16, DAPK and RAR beta genes methylation are strongly associated with clinical data of non-small cell lung cancer, and methylation of p16 and DAPK genes are associated with tobacco smoking.</p>

Addition of ulinastatin to preservation solution promotes protection against ischemia-reperfusion injury in rabbit lung / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The composition of the lung preservation solution used in lung graft procurement has been considered the key to minimize lung injury during the period of ischemia. Low-potassium dextran glucose (LPDG), an extracellular-type solution, has been adopted by most lung transplantation centers, due to the experimental and clinical evidences that LPDG is superior to intracellular-type solutions. Ulinastatin has been shown to attenuate ischemia-reperfusion (I/R) injury in various organs in animals. We supposed that the addition of ulinastatin to LPDG as a flushing solution, would further ameliorate I/R lung injury than LPDG solution alone.</p><p><b>METHODS</b>Twelve male New Zealand white rabbits were randomly divided into 2 groups. Using an alternative in situ lung I/R model, the left lung in the control group was supplied and preserved with LPDG solution for 120 minutes. In the study group 50,000 U/kg of ulinastatin was added to the LPDG solution for lung preservation. Then re-ventilation and reperfusion of the left lung were performed for 90 minutes. Blood gas analysis (PaO₂, PaCO₂), mean pulmonary artery pressure (MPAP) and serum TNF-α level were measured intermittently. The pulmonary water index (D/W), tissue myeloperoxidase (MPO) activity, tissue malondialdehyde (MDA) content and morphologic changes were analyzed.</p><p><b>RESULTS</b>The study group showed significantly higher PaO₂ and lower MPAP at the end of reperfusion. Serum TNF-α level, left lung tissue MPO and MDA in the study group were significantly lower than those in the control group. D/W and pathologic evaluation were also remarkably different between the two groups.</p><p><b>CONCLUSIONS</b>This study indicated that better lung preservation could be achieved with the use of an ulinastatin modified LPDG solution. Ulinastatin further attenuated lung I/R injury, at least partly by reducing oxidative reactions, inhibiting the release of inflammatory factors and neutrophils immigration.</p>

Diagnosis and treatment of pulmonary mucosa-associated lymphoid tissue lymphoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Primary non-Hodgkin's lymphoma in lung is very rare, and the most common among them is mucosa-associated lymphoid tissue lymphoma (MALToma), whose clinical features and laboratory characteristics are poorly defined, making diagnosis difficult. The purpose of this study was to study the diagnosis and treatment of pulmonary MALToma.</p><p><b>METHODS</b>The clinical data of 12 patients treated for MALToma between August 1992 and December 2005 were analyzed.</p><p><b>RESULTS</b>No specific symptoms or signs, or results of bronchoscopy, ultrasonagraphy or bone marrow examination could be found in the 12 patients. Only radiography was useful in diagnosis, though the final diagnosis of all the patients was based on histology and immunohistochemistry. Two patients also had gastric MALToma. Operations were performed on 6 patients, including 5 radical operations and 1 partial resection: 4 patients also received adjuvant chemotherapy. One patient experienced recurrence 152 months after the operation, while the other 5 patients have survived disease-free. Four patients were treated with chemotherapy alone, two of whom experienced complete remission and the others partial remission. The final 2 patients received no treatment and had survived for 7 and 27 months respectively. All the patients were still alive at the most recent follow-up, 7 to 160 months (mean 71.3 months).</p><p><b>CONCLUSIONS</b>Except radiography, no specific clinical manifestations could be identified for pulmonary MALToma. The final diagnosis should be based on histology and immunohistochemistry. Several treatment methods can be used to achieve good outcomes.</p>

Applied anatomy of the lower cervical pedicle screw insertion / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To ascertain an accurate approach to inserting the pedicle screw into C3-C7 segments of the cervical vertebra.</p><p><b>METHODS</b>Anatomic morphology of lateral mass and pedicle, and their anatomic relationship with the adjacent tissue were observed on C3-C7 segments of 25 adult embalmed cadavers (50 sides).</p><p><b>RESULTS</b>1) The inferior edge of the base of the posterior tubercle of the transverse process and the inferior edge of the pedicle were connected with each other on 25 adult embalmed cadavers (50 sides). The transverse section which passed through the median point between the superior edge and the inferior edge of the base of the posterior tubercle of the transverse process, and the transverse section which passed through the central axis between the superior edge and the inferior edge of the pedicle, were in the same horizontal plane. The superior and inferior position of placing the pedicle screw was determined by this transverse section, which passed through the median point between the superior and the inferior edge of the base of the posterior tubercle of the transverse process. 2) There was a directed internal-downwards "triangular sulcule" between the base of the posterior tubercle of the transverse process and the anterolateral edge of the inferior articular process. The anterior wall of the triangular sulcule was the base of the posterior tubercle of the transverse process, the posterior wall was the anterolateral edge of the inferior articular process, and the bottom of the sulcule was connected with the interior edge of the pedicle. The vertical length between the top of triangle and the planes of inferior edge of the pedicle was (2.78+/-1.71) mm. The inferior edge of the cervical pedicle could be detected using a blunt probe along the "triangular sulcule" between the base of the posterior tubercle of the transverse process and the anterolateral edge of the inferior articular process in surgical operation. 3) The lateral fovea of the articular process was observed on all lateral masses (50 sides). The internal and external position of the entrance point could depend on anatomic landmarks: the lateral edge of the lateral fovea of the articular process. The horizontal length between the lateral fovea of the articular process and the entrance point was (3.14+/-1.45) mm. 4) The diameter of pedicle screw, about (2.78+/-1.71) mm, was the transverse diameter of the cancellous bone of the greatest narrow part of the cervical pedicle.</p><p><b>CONCLUSIONS</b>The median point between the superior edge and the inferior edge of the base of the posterior tubercle of the transverse process, the lateral fovea of the articular process, and the triangular sulcule between the base of the posterior tubercle of the transverse process and the anterolateral edge of inferior articular process, are easy to be exposed and identified in surgical operation. The pedicle screw can be precisely inserted through this method.</p>

Selective determination of dopamine in the presence of high concentration of ascorbic acid with L-cysteine modified glassy carbon electrodes / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish an assay system for determination of dopamine (DA) in the presence of ascorbic acid (AA) with L-cysteine modified glassy carbon electrode.</p><p><b>METHODS</b>L-cysteine was modified onto glassy carbon electrode electrochemically, and with this modified electrode, dopamine was determined by linear sweep stripping voltammetry.</p><p><b>RESULTS</b>L-cysteine polymer-modified electrode had strong catalytic effect towards the electrochemical oxidation of DA. The modified electrode showed good properties in determination of DA with coexisting AA. Under selected conditions, the linearity of DA was in the range of 2.0 x 10(-7) - 1.0 x 10(-4) mol/L with the detection limit of 2.0 x 10(-8) mol/L. The stability, reliability and recovery of this L-cysteine-modified electrode based on electrochemical method were also satisfactory.</p><p><b>CONCLUSION</b>L-cysteine-modified electrode can avoid the interference by AA for determination of DA.</p>

Establishment of human ovarian carcinoma cell lines with directional highly lymphatic metastasis and study of their biological characteristics / 中华妇产科杂志

Objective To establish a human ovarian carcinoma cell line with directional highly lymphatic metastasis and to study their biological characteristics.Methods The clone cells of ovarian carcinoma,SKOV3,were inoculated into the hind foot pad of nude mice.The cancer cells of lymph node metastatic foci were transplanted into nude mice again when the metastatic nude of mice were observed.After repetition of this procedure for 3 cycles,the metastatic rate and the metastatic paths were observed in nude mice of every passage.We used limited dilution method to separate and select colonial cells with directional highly lymphatic metastatic potentials from the lymphatic metastasis of human ovarian carcinoma cell line SKOV3.The ceils with biological characteristics were assayed by growth curve,HE staining,karyotype analysis,nude mice transplantation and immunohistochemistry,respectively.Results We established a series of cell lines from lymph node metastasis and designated them as SKOV3-PM1,SKOV3-PM2 and SKOV3-PM3 cell strain.When the cells of SKOV3-PM3 were injected into the hind foot pad of nude mice, they produced 100%(10/10)spontaneous lymphatic metastasis.The lymphatic metastatic rates(26/10) were stable and higher than the mother cell line(1/10,P

The Dynamic Changes of Soil Beneficial Bacteria in Cotton Continuous Cropping Soil South Xinjiang / 微生物学通报

To research the effect of continuous cropping on cotton soil microorganisms and soil microorgan-isms on grow of cotton,we studied the total numbers of aerobic self-nitrogen-fixing bacteria,potassium bacteria,cellulose decomposing bacteria,phosphate solubilizing bacteria,organic-phosphorus-dissolving bacteria distributed in continuous cropping cotton fields of regimental farm 2 and 3 of the first agricultural division through dilution spread plate method.Results showed that the total numbers of five kinds of bacte-ria was highest in blooming and bolling periods,lowest in seeding periods and higher in before sowing pe-riods.The total numbers of five kinds of bacteria was no notable regular changes with continuous cropping year.The numbers of aerobic self-nitrogen-fixing bacteria at different cotton growth stages in regimental farm 2 was higher than in regimental farm 3 and the numbers change of other bacteria was varied in different cotton growth stages in regimental farm 2 and 3.Soil beneficial bacteria were negatively correlated with a variety of soil nutrient ion and free-living nitrogen fixing bacteria were significantly positive correlated with soil total nitrogen.