Ventilator management for acute respiratory distress syndrome associated with avian influenza A (H7N9) virus infection: A case series / 世界急诊医学杂志（英文）

BACKGROUND: Data on the mechanical ventilation (MV) characteristics and radiologic features for the cases with H7N9-induced ARDS were stil lacking. METHODS: We describe the MV characteristics and radiologic features of adult patients with ARDS due to microbiologically confirmed H7N9 admitted to our ICU over a 3-month period. RESULTS: Eight patients (mean age 57.38±16.75; 5 male) were diagnosed with H7N9 in the first quarter of 2014. All developed respiratory failure complicated by acute respiratory distress syndrome (ARDS), which required MV in ICU. The baseline APACHE II and SOFA score was 11.77±6.32 and 7.71±3.12. The overall CT scores of the patients was 247.68±34.28 and the range of CT scores was 196.3–294.7. The average MV days was 14.63±6.14, and 4 patients required additional rescue therapies for refractory hypoxemia. Despite these measures, 3 patients died. CONCLUSION: In H7N9-infected patients with ARDS, low tidal volume strategy was the conventional mode. RM as one of rescue therapies to refractory hypoxemia in these patients with serious architectural distortion and high CT scores, which could cause further lung damage, may induce bad outcomes and requires serious consideration. Prone ventilation may improve mortality, and should be performed at the early stage of the disease, not as a rescue therapy.

Diallyl disulfide inhibits invasion and metastasis of MCF-7 breast cancer cells in vitro by down-regulating p38 activity / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of diallyl disulfide (DADS) on invasion and metastasis of human breast cancer MCF-7 cells and explore the possible mechanism.</p><p><b>METHODS</b>MCF-7 cells treated with 100, 200, and 400 µmol/L of DADS for 24 h were examined for cell invasion and migration capacities using Transwell assay and wound healing assay, respectively. The protein expression of E-cadherin, vimentin, MMP-9 and p-p38 in the cells were detected with Western blotting. The effect of transforming growth factor-β1 (TGF-β1) as the agonist of p38 activity was tested in antagonizing the effects of DADS.</p><p><b>RESULTS</b>DADS inhibited the invasion and migration of MCF-7 cells in a dose-dependent manner, down-regulated the protein expression of Vimentin and MMP-9 and up-regulated E-cadherin expression in the cells. Treatment with TGF-β1 to up-regulate p38 activity obviously antagonized the inhibitory effect of DADS on the invasion and metastasis of MCF-7 cells.</p><p><b>CONCLUSION</b>DADS can inhibit the invasion and metastasis of MCF-7 cells in vitro by down-regulating p38 activity.</p>

LY294002 blocks the effect of dexamethasone in reducing urine protein in rats by inhibiting PI3K/Akt signaling pathway / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the involvement of PI3K/Akt signaling pathway in the changes of urine protein in adriamycin-induced nephropathic rats treated with dexamethasone and LY294002 (a PI3K inhibitor).</p><p><b>METHODS</b>SD rats were randomized into normal control group, ariamycin-induced nephropathy group (ADR group), ariamycin+dexamethasone group (DEX group), and ADR+DEX+LY294002 group (LY294002 group). On days 7, 14 and 28 after the treatments, 24-h urine was collected from the rats to analyze the total urine proteins. The renal tissues were obtained on day 28 to examine the expressions of p-AKT, AKT and Bad proteins in the cortical tissues using Western blotting; the expression of Bad mRNA in the cortical tissues was measured by QPCR.</p><p><b>RESULTS</b>Urine protein increased progressively in ADR group accompanied by significantly reduced p-AKT/AKT ratio and increased Bad mRNA expression in comparison with those in the normal control group (P<0.05). Urine protein was obviously reduced in DEX group with comparable p-AKT/AKT ratio and Bad mRNA expression level with those in the control group (P>0.05). Urine protein showed no significant reduction in LY294002 group, but the p-AKT/AKT ratio was significantly reduced and Bad mRNA expression was increased compared with those in DEX group (P<0.05).</p><p><b>CONCLUSION</b>Dexamethasone increases the expression of Bad mRNA and reduces urine protein in adriamycin-induced nephropathic rats by activating PI3K/Akt signaling pathway. LY294002 can inhibit PI3K/Akt signaling pathway to block the effect of dexamethasone, suggesting that PI3K/Akt signaling pathway is one of the signaling pathways that mediate the effect of dexamethasone on proteinuria.</p>

microRNA-181b promotes migration and invasion of osteosarcoma cells by targeting N-myc downstream regulated gene 2 / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of miR-181b on the migration and invasion of osteosarcoma cells.</p><p><b>METHODS</b>Three cultured osteosarcoma cell lines and MG-63 cells transfected with miR-181b inhibitor were examined for miR-181b expression using qRT-PCR analysis. The cell migration and invasion of the transfected cells were assessed with Transwell assay. The targets of miR-181b were predicted using a miRNA target prediction software and the results were verified with luciferase reporter assay. The target protein expression in osteosarcoma cells lines was determined by Western blotting, and the cell migration and invasion changes following inhibition of miR-181b or its target protein were assessed using Transwell assay.</p><p><b>RESULTS</b>All the 3 osteosarcoma cells lines showed significantly up-regulated miR-181b expression. Inhibition of miR-181b expression obviously suppressed the migration and invasion of MG-63 cells. Based on luciferase reporter assay, N-myc downstream regulated gene 2 (NDRG2) was identified as the direct target gene of miR-181b, and inhibition of NDRG2 expression significantly reversed the effect of miR-181b on cell migration and invasion in MG-63 cells.</p><p><b>CONCLUSION</b>miR-181b is over-expressed in osteosarcoma cells, and inhibition of miR-181b, which directly targets NDRG2, can suppress the migration and invasion of osteosarcoma cells.</p>

Expression of miR-16 in patients with T lymphoblastic lymphoma/acute lymphoblastic leukemia / 中国实验血液学杂志

This study was purposed to investigate the expression of miR-16 in T lymphoblastic lymphoma/acute lymphoblastic leukemia (T-LBL/ALL) and its relation with target therapy and prognosis. The CD3, cCD3, CD10, CD20, CD34, CD43, CD99, TdT, PAX-5, BCL-2 and Ki67 in paraffin samples from 38 cases of T-LBL/ALL were detected by immunohistochemical labeling; the miR-16 expression level was detected by real-time RT-PCR. Fifteen cases of reactive hyperplasia of lymph nodes were selected as control. The results indicated that among 38 cases of T-LBL/ALL the positive rate of TdT was highest (94.7%), the positive rate of CD34 was lowest (22.1%), the PAX-5 and CD20 were found to be negative. The Ki67 expression level in 39.5% cases exceeded 80%. As compared with reactive hyperplasia of lymph node, the miR-16 expression in T-LBL/ALL was up-regulated, ant its expression level was 4.87-fold of reactive hyperplasia of lymph node (P < 0.05). The overall survival rate in group of miR-16 high expression decreased (P < 0.05). The prognosis of T-LBL/ALL patients with BCL-2 positive expression was better than that of patients with BCL-2 negative expression (P < 0.05). The miR-16 expression correlated with BCL-2 protein (r = 0.51, P < 0.05). It is concluded that the overall survival rate in miR-16 high expression group is higher than that in miR-16 low expression group, suggesting possible relation of miR-16 with prognosis. Moreover, the prognosis in BCL-2 positive expression group is better than that in negative expression group, which may be a factor influencing prognosis.

Expression of blood Th17 and CD4(+) CD25(+) Treg cells in patients with aplastic anemia / 中国实验血液学杂志

This study was aimed to investigate the expression of blood Th17 and CD4(+) CD25(+) regulatory T cells (Treg) in the patients with aplastic anemia (AA). Forty-five patients with AA were enrolled into this study, and were divided into mild aplastic anemia (MAA) group (n = 25) and severe aplastic anemia group (SAA) (n = 20), blood cell count was recorded. 15 healthy donors were enrolled as control. Proportions of blood Th17 and CD4(+) CD25(+) Treg cells were determined by flow cytometry. The serum levels of IL-17, IFN-γ and TNF-α, as well as their concentrations in culture supernatant of phytohemagglutinin (PHA) -stimulated peripheral blood mononuclear cells, were measured by ELISA. The results showed that the proportions of blood Th17 cells and concentration of blood serum IL-17 and IFN-γ increased in patients with SAA, compared with MAA and normal controls, but CD4(+) CD25(+) Foxp3(+) Treg cells obviously decreased in patients with SAA. The concentrations of IL-17 and IFN-γ significantly increased in culture supernatant of SAA group. Hemoglobin level in the patients with AA negatively correlated with the population of Th17 cells and serum IL-17 level, whereas positively correlated with the expression of CD4(+) CD25(+)Treg cells. It is concluded that the increased response of Th17 cells and deficiency of CD4(+) CD25(+) Treg cells present in severe aplastic anemia. The severity of anemia may be related with the imbalance between Th17 and CD4(+) CD25(+)Treg cell response.

Myocardial infarction following recombinant tissue plasminogen activator treatment for acute ischemic stroke: a dangerous complication / 中华医学杂志(英文版)

Thrombolysis with intravenous tissue plasminogen activator (t-PA) is currently an approved therapy for patients with acute ischemic stroke. Acute myocardial infarction (AMI) immediately following t-PA treatment for stroke is a rare but serious complication. A case of acute myocardial infarction (MI) following IV t-PA infusion for acute stroke was observed. This is a 52-year-old male with a known history of hypertension and chest pain, who subsequently developed MI four hours after IV t-PA was administered for acute ischemic stroke. The disruption of intra-cardiac thrombus and subsequent embolization to the coronary arteries may be an important mechanism. In addition, spontaneous recanalization of infarct-related arteries may be associated with greater myocardial salvage and better prognosis.

Rapid construction of a mammalian cell surface display library of full-length human antibodies / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct a mammalian cell surface display library of full-length human antibodies.</p><p><b>METHODS</b>The total RNA was isolated from human peripheral blood mononuclear cells (PBMCs), and the genes encoding the heavy chain variable regions and kappa light chains (VH and Cκ) of the antibodies were amplified by RT-PCR. The amplified VH and Cκ gene sequences were separately inserted into the vector pDGB-HC-TM. The ligation mixtures were transformed into competent E.coli DH5α cells to construct the antibody libraries, and the library sizes and diversity were analyzed. The library DNAs were transfected into CHO cells and the expression of the full-length human antibodies on the surface of CHO cells was analyzed by flow cytometry.</p><p><b>RESULTS</b>The heavy chain gene library constructed showed a diversity of 2.6 × 10(5), and the kappa light chain gene library had a diversity of 2.0 × 10(5). Sequence analysis of 10 clones randomly selected from the constructed heavy chain gene library and 10 from the light chain gene library showed that 8 heavy chain clones and all 10 light chain clones contained correct open reading frames. Flow cytometry demonstrated that all the 18 clones expressed full-length antibodies, which could be detected on CHO cell surfaces. After co-transfection of the heavy chain and light chain gene libraries into CHO cells, the expression of full-length antibodies on CHO cell surfaces was detected with the positive cells reaching 31.5.</p><p><b>CONCLUSIONS</b>A full-length human mammalian display antibody library with a combinatory diversity of 5.2 × 10(10) can be constructed in two weeks, which allows the display of full-length antibodies on mammalian cell surface.</p>

Effects of UV-induced DNA damage on vector ligation and transformation into bacterial cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To study the effects of UV irradiation on DNA ligation and transformation efficiency of the expression vector into competent bacterial cells.</p><p><b>METHODS</b>The expression vector was digested with the restriction enzyme SfiI, and the purified target DNA fragments were exposed to UV light at different wavelengths. Ligation and transformation experiments with the exposed fragments were carried out and the colony number and transformation efficiency were assessed.</p><p><b>RESULTS</b>The transformation efficiency of the DNA with a 5-min exposure to 302 nm UV was 60 colonies per nanogram of the DNA, as compared with 20400 for the DNA exposed to 365 nm UV. The time course experiment showed that prolonged DNA exposure to 365 nm UV light was associated with lowered transformation efficiency. DNA exposure for 30 min caused a reduction of the transformation efficiency to lower than 50% compared to that of DNA without UV exposure. But with a 15 min exposure, the DNA maintained a transformation efficiency more than 70%, which was sufficient for most molecular biology experiments.</p><p><b>CONCLUSION</b>In construction of the expression vector, it is advisable to prevent the target DNA from UV exposure. When UV exposure is essential, we suggest that 365 nm UV be used and the exposure time controlled within 15 min.</p>

Regulation of rat airway smooth muscle cell proliferation by mitochondrial ATP-sensitive K(+) channel in asthmic rats / 生理学报

The objective of this paper was to investigate the effect and mechanism of mitochondrial ATP-sensitive K(+) (MitoK(ATP)) channel on the proliferation of airway smooth muscle cells (ASMCs) in asthmic rats. Thirty-six Sprague-Dawley (SD) rats were randomly assigned into 2 groups (18 in each): (1) Asthma group: the asthmic rat model was established by ovalbumin (OVA) sensitization and excitation; (2) Normal group: rats were subjected to inhalation of equal amount of normal saline. The rat ASMCs were isolated from fresh lung tissues and cultured respectively as follows: (1) CONTROL GROUP: normal ASMCs were cultured under normoxia for 24 h; (2) Diazoxide group: normal ASMCs were cultured under normoxia for 24 h with diazoxide (an opener of MitoK(ATP) channel); (3) 5-HD group: normal ASMCs were cultured under normoxia for 24 h with 5-hydroxydecanoate (5-HD) (an antagonist of MitoK(ATP) channel); (4) Asthma group: Asthmic ASMCs were cultured under normoxia for 24 h; (5) Asthma + diazoxide group: Asthmic ASMCs were cultured under normoxia with diazoxide for 24 h; (6) Asthma + 5-HD group: Asthmic ASMCs were cultured under normoxia with 5-HD for 24 h. The mitochondrial membrane potential (ΔΨm) was detected using Rhodamine 123 (R-123). The level of reactive oxygen species (ROS) was detected by DCF fluorescence. The expression of nuclear factor-kappa B (NF-κB) mRNA was examined by RT-PCR. The proliferation and apoptosis of rat ASMCs were examined respectively by MTT colorimetric assay and cell cycle analysis. The results were as follows. (1) After exposure to diazoxide for 24 h, the R-123 fluorescence intensity, the ROS level, NF-κB mRNA expression and the MTT absorbance value (A value) in normal ASMCs were significantly increased, and the apoptosis of rat ASMCs was significantly decreased compared to the control group (P<0.05). However, there was no significant changes in those indices after the normal ASMCs had been exposed to 5-HD for 24 h. (2) In Asthma and Asthma + diazoxide groups, the R-123 fluorescence intensity, ROS level and the MTT A value were markedly increased, and the apoptosis was markedly decreased compared to control group (P<0.05). These changes were more obvious in Asthma + diazoxide group than those in Asthma group (P<0.05). 5-HD partly weakened the effect of asthma on the R-123 fluorescence intensity, ROS level and the MTT A value and the apoptosis of rat ASMCs (P<0.05). R-123 fluorescence intensity and NF-κB mRNA expression were positively correlated with ROS level. NF-κB mRNA expression was positively correlated with the MTT A value and negatively correlated with the apoptosis of rat ASMCs. All the results suggest that the opening of MitoK(ATP) channel followed by a depolarization of ΔΨm contributes to the increase in ROS level and NF-κB mRNA expression in rat ASMCs and to the unbalance between cell proliferation and apoptosis of ASMCs induced by asthma. This might be a mechanism of the development of airway remodeling in asthma.

Effect of opening of mitochondrial ATP-sensitive K(+) channels on the expression of hypoxia inducible factor-1alpha and cell proliferation in pulmonary arterial smooth muscle cells of rats / 生理学报

The objective of this paper was to investigate the effect of mitochondrial ATP-sensitive K(+) (MitoK(ATP)) channels on the expression of hypoxia inducible factor-1alpha (HIF-1alpha) and cell proliferation in pulmonary arterial smooth muscle cells (PASMCs) of rats. Cultured PASMCs were divided into six groups as follows: (1) normoxia group: cultured under normoxia for 24 h; (2) normoxia + diazoxide group: cultured under normoxia with diazoxide, an opener of MitoK(ATP) channel, for 24 h; (3) normoxia + 5-HD group: cultured under normoxia with 5-hydroxydecanoate (5-HD), an antagonist of MitoK(ATP) channel, for 24 h; (4) hypoxia group: cultured under hypoxia (37 degrees C, 5% O(2), 5% CO(2), 90% N(2)) for 24 h; (5) hypoxia + diazoxide group: cultured under hypoxia (37 degrees C, 5% O(2), 5% CO(2), 90% N(2)) with diazoxide for 24 h; (6) hypoxia + 5-HD group: cultured under hypoxia (37 degrees C, 5% O(2), 5% CO(2), 90% N(2)) with 5-HD for 24 h. The relative changes in mitochondrial potential were tested with Rhodamine 123 (R-123) fluorescence technique. Immunohistochemical method was used to trace the expression of HIF-1alpha. The proliferation of PASMCs was examined by MTT colorimetric assay. The results were as follows: The intensity of R-123 fluorescence in normoxia + diazoxide group was significantly increased as compared with that in normoxia group (P<0.05), and the intensity of R-123 fluorescence in hypoxia + diazoxide group was also significantly increased as compared with that in hypoxia group (P<0.05). 24-hour hypoxia or 24-hour hypoxia + diazoxide markedly increased the intensity of R-123 fluorescence in PASMCs as compared with normoxia (P<0.05), and the change was more prominant in hypoxia + diazoxide group than that in hypoxia group (P<0.05). There was no significant difference in the intensity of R-123 fluorescence between normoxia group and normoxia + 5-HD group (P>0.05). However, 5-HD weakened the effect of 24-hour hypoxia on the intensity of R-123 fluorescence. The intensity of R-123 fluorescence in hypoxia + 5-HD group was significantly decreased as compared with that in hypoxia group (P<0.05). After exposure to hypoxia or hypoxia + diazoxide for 24 h, the expression of HIF-1alpha and the proliferation of PASMCs were significantly increased as compared with that in normoxia or normoxia + diazoxide group (P<0.05), and the change was more significant in hypoxia + diazoxide group than that in hypoxia group (P<0.05). There was no significant difference in the expression of HIF-1alpha and the proliferation of PASMCs between normoxia group and normoxia + 5-HD group (P>0.05). However, the expression of HIF-1alpha and the proliferation of PASMCs in hypoxia + 5-HD group were significantly decreased as compared with that in hypoxia group (P<0.05). All these results suggest that the opening of MitoK(ATP) channels followed by a depolarization of mitochondrial membrane might contribute to the increase of the expression of HIF-1alpha and the proliferation of PASMCs. This might be a mechanism of the development of hypoxic pulmonary hypertension.

The relationships among reactive oxygen species, hypoxia-inducible factor 1alpha and cell proliferation in rat pulmonary arterial smooth muscle cells under hypoxia / 生理学报

The objectives of this paper were to observe the changes of reactive oxygen species (ROS) in rat pulmonary arterial smooth muscle cells (PASMCs) under hypoxic condition and to test if hypoxia-induced proliferation of PASMCs was mediated by ROS. PASMCs were divided into three groups: normal group, hypoxia group and hypoxia + Mn-TBAP (a ROS scavenger) group. The level of ROS was determined by a laser scanning confocal microscope. The expression of hypoxia-inducible factor 1alpha (HIF-1alpha) mRNA was detected by semi-quantitative reverse transcription PCR (RT-PCR). HIF-1alpha protein was detected using immunohistochemical staining, and the proliferation of PASMCs was examined by MTT colorimetric assay. The results were as follows: (1) The level of ROS in hypoxia group was significantly increased as compared with that in the normal group (P<0.05). The level of ROS in hypoxia + Mn-TBAP group was significantly decreased as compared with that in hypoxia group (P<0.05), but was increased as compared with that in the normal group (P<0.05). (2) The expressions of HIF-1alpha mRNA and protein in hypoxia group and hypoxia + Mn-TBAP group were increased as compared with those in the normal group (P<0.05), and these changes were more significant in hypoxia group than those in hypoxia + Mn-TBAP group. (3) The proliferation of PASMCs in hypoxia group was more obvious than that in the normal group and hypoxia + Mn-TBAP group (P<0.05), and the proliferation of PASMCs in hypoxia + Mn-TBAP group was increased more significantly than that in the normal group (P<0.05). The results indicate that ROS is significantly increased in rat PASMCs under hypoxia, and that ROS affects the expression of HIF-1alpha and the proliferation of PASMCs under hypoxia. Therefore, ROS may play an important role in the pathogenesis of pulmonary hypertension and hypoxic signal transductions.

Study on the correlation between spiral CT features and expression of phosphatase and tensin homlogy deleted on chormosome ten,basic fibroblast grouth factor in gastric carcinoma / 中华放射学杂志

Objective To investigate the spiral CT features of gastric carcinoma in the invasion and metastasis and its correlation with the expression of phosphatase and tensin horology deleted on chormosome ten(PTEN)and basic fibroblast grouth factor(bFGF).Methods Spiral CT plain scan and triphasic enhanced scans were performed in 83 patients.The postoperative specimens were embedded with paraffin to obtain 5?m thickness tissues and stained with HE and immunohistochemistry.Spiral CT findings were compared with the expression of phosphatase and tensin horology deleted on chormosome ten(PTEN)and basic fibroblast growth factor(bFGF).Results(1)The accuracy of spiral CT in T and N staging of gastric carcinoma was 94.0%(78/83)and 89.2%(74/83),respectively.(2)The expression of PTEN was 47.0%(39/83)in gastric carcinoma.The expression of PTEN in T_(3.4)(40.8%,29/71)and N_(1+2) (38.3%,23/60)gastric carcinoma was significantly lower than that of T_2(10/12)and N_0(16/23)gastric carcinoma,respectively(X~2=7.439,P=0.006;X~2=6.511,P=0.011).(3)The expression of bFGF was 63.9%(53/83)in gastric carcinoma.The expression of bFGF in T(3.4)(70.4%,50/71)and N_(1+2) (71.7%,43/60)gastric carcinoma was significantly higher than that of T_2(3/12)and N_0(10/23)gastric carcinoma,respectively(X~2=7.314,P=0.007;X~2=5.724,P=0.017).(4)Both PTEN-positive expression and bFGF-positive expression were detected in 16 specimens.The expression of PTEN(41.0%, 16/39)was negatively correlated with that of bFGF(30.2%,16/53)(r=-0.447,P=0.000). Conclusion Spiral CT triphasic enhanced scans combined with biologic characteristics can improve diagnostic accuracy of gastric carcinoma in the invasion,metastasis and prognosis.