Coagulation function and hemorrhagic diseases in preterm infants with different gestational ages / 中国当代儿科杂志

OBJECTIVE@#To study the correlation between coagulation function and gestational age in preterm infants and the possible value of coagulation function measurement in predicting hemorrhagic diseases.@*METHODS@#The clinical data of preterm infants who were hospitalized between September 2016 and August 2017 were collected. The coagulation indicators were measured within 2 hours after birth. According to the gestational age, the preterm infants were divided into late preterm infant group (n=322), early preterm infant group (n=241) and extremely/very early preterm infant group (n=128). Coagulation function was compared among the three groups, as well as between the preterm infants with and without hemorrhagic diseases within 3 days after birth.@*RESULTS@#There were significant differences in thrombin time (TT), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen degradation product (FDP) and D-dimer (DD) among the three groups (P<0.05). APTT, PT, FDP and DD were negatively correlated with gestational age, while TT was positively correlated with gestational age (P<0.05). The preterm infants with hemorrhagic diseases had a longer APTT and a higher level of DD (P<0.05).@*CONCLUSIONS@#Coagulation function gradually becomes mature in preterm infants with the increase in gestational age. Abnormal APTT and DD indicate that preterm infants may have a higher risk of hemorrhagic diseases.

Construction and characterization of the stk and stp1 knockout mutant in streptococcus suis type 2 / 医学研究生学报

Objective Serine /threonine kinases (STK) and phosphatases (STP) regulate various physiological activities of prokaryotes by reversible phosphorylation of proteins .This paper aimed to study the effects of simultaneous deletion of the stk and stp1 genes on the biological characteristics and pathogenicity of streptococcus suis type 2, the Chinese virulent strain 05ZYH33. Methods The double mutant of the stk and stp1 genes of 05ZYH33 was constructed by homologous recombination .The biological characteristics of the wild strain 05ZYH33 and the mutant strain Δstk/stp1 were compared.The effects of the stk and stp1 deletion on bacterial virulence was analyzed using cell adhesion assay , anti-phagocytosis assay and the mouse model of infection . Results RT-PCR showed that the stk and stp1 genes were replaced by the spectinomycin resistance gene Spc r and the mutant strain was successfully constructed .Experi-ments of biological characterization revealed gradually increased value of 05ZYH33 and Δstk/stp1 at 2 hours after inoculation and a plateau period at 7 hours.The logarithmic phase of the mutant strain (A600≈0.4) was 1 hour later than that of the wild one , and the bacterial den-sity of the former was lower than that of the latter after the plateau pe -riod (0.8 vs 1.0).On the blood plates of 05ZYH33 and Δstk/stp1 were observed greyish, round, semitransparent, wet and smooth-sur-faced tiny bacterial colonies , around which there were hemolysis rings with no significant differences in colony morphology and hemolytic ac -tivity.In the experiment on pathogenicity , the mice of the 05ZYH33 group all died within 12 hours while 9 of the 30 mice in the Δstk/stp1 group died within 12 hours and all died within 24 hours. Conclusion The simultaneous deletion of the stk and stp1 genes may mainly affect the regulation of the proteins associated with bacte -rial proliferation and division.

Development of an environment-friendly and sterile four- blade vaginal dilator for LEEP surgery / 中国医学装备

Objective: To develop an environment-friendly and sterile four- blade vaginal dilator so as to resolve the problem of polluting environment that petroleum-based plastics released hydrogen chloride, dioxin and other poisonous and cancerogenic substance. Methods: The lower blade of the environment-friendly and sterile four-blade vaginal dilator was used as fixed blade, and upper blade, left blade and right blade were extensible and closable. And in the left and right blades, there were built-in smog exhaust tubes. And based on the previous invention of the twin-blades vaginal dilator, the device has been redesigned and developed by adding the left blades, right blades, locating sleeve and other related parts. Results: When the device expanded, both of left and right blades could extend out, and when it closed, both of them could be folded into the upper and lower blades. Therefore, it was safety and effective. Besides, the built-in smoking tubes of left and right blades could quickly exhaust harmful smog by the closest distance, and the plastics used in this device was not only environmentally friendly, but also it was insulation and cost-effective. Conclusion: The environment-friendly and sterile four-blades vaginal dilator used in LEEP surgery resolved two problems included the constructs of imported four-blades vaginal dilator were complex and the left and right blades couldn't extend out. And it effectively enhance the expand distance between left and right blades, and it enlarges operation field and surgery space. Besides, the use of the environmentally friendly plastics avoids the environmental pollution caused by the release of hydrogen chloride, dioxins and other toxic and carcinogenic substances when built-out smoking tubes and petroleum base plastics were incinerated. Therefore, it enhances the surgical quality.

Exposure to Radon and Kidney Cancer: A Systematic Review and Meta-analysis of Observational Epidemiological Studies / 生物医学与环境科学（英文）

OBJECTIVE@#To evaluate the possible association between radon exposure and kidney cancer.@*METHODS@#We performed a systematic review and a meta-analysis based on random effect models to provide a pooled association measure.@*RESULTS@#We subjected 8 studies (overall relative risks and 95% confidence intervals: 1.01, 0.72 to 1.43, I2 = 64.4%) to meta-analysis. Subgroup analysis revealed a marginally significant association between radon exposure and kidney cancer in studies conducted in Europe. Two population-based studies provided no evidence for the increased risk of kidney cancer in the general population.@*CONCLUSION@#The association between radon and kidney cancer remains unclear but cannot be excluded because of its biological plausibility and the limited number and quality of existing studies. Additional data from the general population and well-designed miner cohort studies are needed to reveal the real relationship between radon exposure and kidney cancer.

Platelet-rich fibrin combined with collagen membrane for repairing calvarial bone defects / 中国组织工程研究

BACKGROUND: At present, there are some studies on applying platelet-rich fibrin (PRF) or collagen membrane in guided bone regeneration to promote the bone defect repair, while there is no report about their combined use versus single use in the bone defect repair. OBJECTIVE: To compare the bone regeneration ability of PRF, collagen membrane and their combined membrane in the bone defect repair.METHODS: Twenty-two Japanese big ear rabbits were selected to establish three bone defects in the calvarial bone, and then PRF, collagen membrane and PRF/collagen membrane composite were respectively implanted into the three defect regions. At 2, 4, 8, 12 weeks after implantation, tissue repair and regeneration in the bone defect regions were observed by X-ray and hematoxylin-eosin staining. RESULTS AND CONCLUSION: (1) Postoperative 2-week X-ray showed blurred density increase in the margin of bone defect in the composite membrane group, as well as increased density in the PRF group, while it was rarely seen in the collagen membrane group. At 12 weeks after implantation, in the composite membrane group, the bone density in the defect area was similar to the surrounding bone tissue; in the collagen membrane group, annulus-shaped density was enlarged, but the density in the defect region was still lower than that in the surrounding bone tissues; and in the PRF group, the lower density was seen in the individual parts of bone defect region compared with the surrounding bone tissues. (2) Histological observation: At 2 weeks after implantation, new fibrous connective tissues and newborn capillaries were seen around the defect area in the composite membrane group, while less fibrous connective tissues and capillaries were found in the other two groups. At 12 weeks after implantation, in the composite membrane group, a great amount of bone cells arranged regularly in the bone defect area with the presence of thickened trabecular bone and mature bone formation; in the PRF group, there were visible bone cells and increased number of trabecular bone, but less bone formation than the composite membrane group; in the collagen membrane group, there were few bone tissues formed with osteoblasts, osteoclasts and obvious bone lacuna. In conclusion, the PRF/collagen composite membrane shows better osteogenic effects than their use alone.

Platelet-rich fibrin combined with collagen membrane for repairing calvarial bone defects / 中国组织工程研究

BACKGROUND: At present, there are some studies on applying platelet-rich fibrin (PRF) or collagen membrane in guided bone regeneration to promote the bone defect repair, while there is no report about their combined use versus single use in the bone defect repair. OBJECTIVE: To compare the bone regeneration ability of PRF, collagen membrane and their combined membrane in the bone defect repair.METHODS: Twenty-two Japanese big ear rabbits were selected to establish three bone defects in the calvarial bone, and then PRF, collagen membrane and PRF/collagen membrane composite were respectively implanted into the three defect regions. At 2, 4, 8, 12 weeks after implantation, tissue repair and regeneration in the bone defect regions were observed by X-ray and hematoxylin-eosin staining. RESULTS AND CONCLUSION: (1) Postoperative 2-week X-ray showed blurred density increase in the margin of bone defect in the composite membrane group, as well as increased density in the PRF group, while it was rarely seen in the collagen membrane group. At 12 weeks after implantation, in the composite membrane group, the bone density in the defect area was similar to the surrounding bone tissue; in the collagen membrane group, annulus-shaped density was enlarged, but the density in the defect region was still lower than that in the surrounding bone tissues; and in the PRF group, the lower density was seen in the individual parts of bone defect region compared with the surrounding bone tissues. (2) Histological observation: At 2 weeks after implantation, new fibrous connective tissues and newborn capillaries were seen around the defect area in the composite membrane group, while less fibrous connective tissues and capillaries were found in the other two groups. At 12 weeks after implantation, in the composite membrane group, a great amount of bone cells arranged regularly in the bone defect area with the presence of thickened trabecular bone and mature bone formation; in the PRF group, there were visible bone cells and increased number of trabecular bone, but less bone formation than the composite membrane group; in the collagen membrane group, there were few bone tissues formed with osteoblasts, osteoclasts and obvious bone lacuna. In conclusion, the PRF/collagen composite membrane shows better osteogenic effects than their use alone.

Chemical constituents from Gentianella acuta / 中成药

AIM To study the chemical constituents from Gentianella acuta (Michx.) Hulten.METHODS The 30％ and 90％ ethanol fractions of 70％ ethanol extract from G.acuta were isolated and purified by silica,ODS and preparative HPLC column,then the structures of obtained compounds were identified by spectral data.RESULTS Nine compounds were isolated and identified as sinenoside Ⅰ (1),(+)-lariciresinol-4,4'-0-bis-β-D-glucopyranoside (2),(+)-8-hydroxylariciresinol-4'-O-β-D-glucopyranoside (3),(+)-lariciresinol-4-O-3-D-glucopyranoside (4),(7S,8R)-erythro-7,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-4-O-β-D-glucopyranoside (5),(7S,8R)-erythro-4,9,9'-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-7-O-β-D-glucopyranoside (6),(7S,8R)-erythro-4,7,9-trihydroxy-3,3'-dimethoxy-8-O-4'-neolignan-9'-O-β-D-glucopyranoside (7),balanophonin (8),urolignoside (9).CONCLUSION Compounds 2-9 are isolated from genus Gentianella for the first time.

Construction, expression and identification of recombinant plasmid encoding bifunctional protein sflk1-IFN-gamma / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To construct, express and identify the recombinant plasmid pcDNA3.1(+)/sflk1-IFN-gamma encoding bifunctional protein sflk1-IFN-gamma (soluble fetal liver kinase 1 and interferon-gamma).</p><p><b>METHODS</b>sflk1 and IFN-gamma gene fragments were cloned by RT-PCR, and then inserted into pcDNA3.1(+) plasmid between BamHI-EcoRI and XhoI-XbaI restriction sites to form the recombinant plasmid pcDNA3.1(+)/sflk1-IFN-gamma. The recombinant sflk1-IFN-gamma transiently expressed in COS-7 cells was detected by ELISA and Western blotting. Bioactivities of sflk1-IFN-gamma fusion protein were identified by proliferation inhibition assay with H5V cells and NK activity assay.</p><p><b>RESULTS</b>pcDNA3.1(+)/sflk1-IFN-gamma can be effectively expressed in COS-7 cells. Concentrations of sflk1 and IFN-gamma in culture supernatants of pcDNA3.1(+)/sflk1-IFN-gamma transfected COS-7 cells were (20.85+/-2.48) ng/ml and (1.08+/-0.09) ng/ml, respectively. Western blotting showed that the molecular weight of sflk1-IFN-gamma fusion protein was about 130 kDa, while that of sflk1 was 115 kDa. The supernatants of transfected cells significantly inhibited the proliferation of H5V cells stimulated by mouse VEGF 164 and enhanced the NK activity of splenocytes, demonstrating that sflk1-IFN-gamma fusion protein possessed the bioactivities of both sflk1 and IFN-gamma.</p><p><b>CONCLUSION</b>The constructed plasmid pcDNA3.1(+)/sflk1-IFN-gamma can be effectively expressed in eukaryotes. The expressed sflk1-IFN-gamma fusion protein has the biological activities of both sflk1 and IFN-gamma.</p>

Effect of low-dose hydroxyurea with sodium butyrate on globin gene expression in human erythroid progenitor cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of combined use of low-dose hydroxyurea (HU) and sodium butyrate (NaB) on the expression of 7 globin genes (zeta, alpha, epsilon, Ggamma, Agamma, delta, and beta) in human erythroid progenitor cells.</p><p><b>METHODS</b>Human erythroid progenitor cells were cultured using a two-step liquid culture system and treated with HU and NaB either alone or in combination. The inhibitory effects of the agents on the cell growth were monitored with trypan blue exclusion assay, and the changes in the mRNA of the 7 globin genes were detected using RT-PCR.</p><p><b>RESULTS</b>Low-dose HU combined with NaB resulted in significantly lower inhibition rate of the erythroid progenitor cells than routine dose HU and NaB used alone (28.56% and 38.80%, respectively, P<0.05). Compared with untreated cells (0.653-/+0.092 and 0.515-/+0.048), HU combined with NaB significantly increased the expression of Ggamma-and Agamma- mRNA (1.203-/+0.018 and 0.915-/+0.088, respectively, P<0.05), and HU and NaB used alone produced similar effects (1.305-/+0.016 and 0.956-/+0.029 for HU, and 1.193-/+0.070 and 0.883-/+0.012 for NaB, P>0.05). HU and NaB, either used alone or in combination or at different doses, caused no significant changes in the other globin genes (zeta, alpha, epsilon, delta and beta) (P>0.05).</p><p><b>CONCLUSION</b>Low-dose HU combined with NaB can up-regulate gamma globin gene expression, especially Ggamma-mRNA expression, to decrease the growth inhibition on human erythroid progenitor cells in vitro, but produces no significant effect on the expressions of zeta, alpha, epsilon, delta and beta genes.</p>

Differentiation of Dendritic Cells from Embryonic Stem Cells / 实用儿科临床杂志

Objective To investigate the method of directed differentiation dendritic cells from embryonic stem cells(ESC) and to amplify high purity DCS in vitro for immunity therapy.Methods E14 ESC line were generated ESC-derived dendritic cells(ES-DC) in complete medium further supplemented with granulocyte-macrophage colony-stimulating factor(GM-CSF) and interleukin-3(IL-3).ES-DCs was used flow cytometry to determine CD11c,CD80,CD86,MHC-Ⅱ cell surface phenotype. Lipopolysaccharide (LPS) were added to induce the ES-DCs matured. The matured ES-DCs was harvested 24 hours later to be identified with morphology, transmission electron microscopy, analyzed by flow cytometry and compared with the immatured ES-DCs phenotype. The antigen presenting was evaluated by mixed lymphocyte responses.Results The ES-DC had obviously dendritic processes under scanning electron microscope . The immature DCs express low level of CD11c(4.33±0.23)%,CD80 (7.62±0.19) %, CD86 (4.77±1.22) % and MHC-Ⅱ (9.68±0.15) %, but the mature DCs express higher lerve of CD11c(47.36±2.68)%,CD80 (74.4±1.47) %, CD86 (29.77±2.00) % and MHC-Ⅱ (87.56±2.75) %. MLR showed that ES-DCs could effectively stimulate lymphocyte to proliferate.Conclusion These results provide evidence that DCs can be generated from E14 ESC with GM-CSF and IL-3, express high level of CD11c,CD80, CD86, MHC-Ⅱ and can effectively stimulate lymphocyte to proliferate. ES cells may become new origin for DCs which provided the immunotherapy.

Anti-metastatic effect of vascular endothelial growth factor receptor 2 extracellular domain gene-modified dendritic cell vaccination in murine model with experimental pulmonary metastasis / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the anti-metastatic effect of vascular endothelial growth factor receptor 2 extracellular domain gene-modified dendritic cell (DC-sVEGFR-2) vaccination.</p><p><b>METHODS</b>Dendritic cells (DC) were electroporated with pcDNA3. 1/sVEGFR-2 plasmid DNA. Expression of sVEGFR-2 was determined by ELISA. For immunization, C57BL/6 mice were intravenously injected three times with 1 x 10(5) cells per mouse of DC, pcDNA3. 1-transfected DC (DC-vector) , DC-sVEGFR-2, or 100 microl of PBS at 7-day intervals. At 10 days after the last immunization, the immunized mice were subjected to assessment of cytotoxic T lymphocyte ( CTL) response to VEGFR-2, alginate bead analysis of tumor cell-induced angiogenesis, and observation of the anti-metastatic effect in B16 melanoma metastasis model. CTL activity was determined by a standard 4-h 51Cr release assay against VEGFR-2 + vascular endothelial cell line H5V, 3LL cells stably transfected with pcDNA3. 1/sVEGFR-2 (3LL,-sVEGFR-2), and VEGFR-2- cell lines EL-4 and 3LL. Monoclonal antibodies GK1.5 anti-CD4 and 2.43 anti-CD8 were used to deplete in vivo CD4 + T cells and CD8' T cells, respectively.</p><p><b>RESULTS</b>DC-sVEGFR-2 could effectively express sVEGFR-2, whereas DC-vector and DC could not. Immunization of mice with DC-sVEGFR-2 significantly induce CTL activity against VEGFR-2 + cell lines H5V and 3LL-sVEGFR-2, however, no significant CTL activity was observed when VEGFR-2- syngeneic cell lines EL-4 and 3LL. were used as target cells, implying this CTL activity was VEGFR-2 specific. Alginate bead analysis of in vivo neoangiogenesis showed that the inhibition reached 50% in mice vaccinated with DC-sVEGFR-2 compared with mice vaccinated with DC, DC-vector or PBS. Anti-metastatic experiment showed that profound reduction in pulmonary metastases was found in mice immunized with DC-sVEGFR-2, while mice immunized with PBS, DC, DC-vector developed extensive pulmonary metastases. The number of tumor nodules on lung surface decreased by 81.9% in mice immunized with DC-sVEGFR-2 when compared with mice immunized with DC-vector (49.7+/-12.7 vs. 9.0+/-3.2). In vivo T cell subset depletion experiments showed that the anti-metastatic effect of DC-sVEGFR-2 vaccination was abrogated in CD8 + T cell-depleted but not in CD4+ T cell-depleted mice.</p><p><b>CONCLUSION</b>Immunization of mice with DC-sVEGFR-2 could break self-tolerance and induce a significant CTL response to VEGFR-2, leading to profound inhibition of tumor-cell induced angiogenesis and metastasis. This anti-metastatic effect is mainly mediated by CD8+ T cells.</p>