[The value of preservation of subvalvular structures in patients with mitral and aortic valve replacement surgery and its effect on left ventricular contractility]

Objective: To discuss the clinical value of preserving subvalvular structure in mitral and aortic valve replacement surgery and its effect on left ventricular contractility. Methods: A total of 97 patients who underwent mitral valve replacement surgery in the Adult Cardiac Surgery of Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital from June 2016 to December 2018 were selected as the research subjects, of whom 45 cases were preserved subvalvular structure and 52 cases were in the total resection group (intraoperative total resection of the mitral valve and subvalvular chordae tendineae). General cardiac function indexes and left ventricular function quantitative indexes were compared before and in 3 months and 6 months after the operation of the two groups; The changes of the overall longitudinal strain of the long axis of the apex and the overall circumferential strain of the short axis of the left ventricle determined by the two-dimensional speckle tracking technology were compared before and after the operation. Results: The ages of the patients in the preservation group and the total resection group were (41.8±11.3) and (43.3±10.6) years old, respectively, and the male proportions were 58.0% (26 cases) and 44.0% (23 cases), respectively, with no significant difference (all P>0.05). The aortic occlusion time and cardiopulmonary bypass time of the patients in the preservation group were (57.8±4.5) and (78.6±6.7) min, respectively, which were longer than those in the total resection group [(48.1±4.4) and (48.1±4.4) min, respectively] (all P<0.05). The left atrial pressure of the patients in the preservation group at shutdown was (8.4±1.8) mmHg (1 mmHg=0.133 kPa), which was lower than that of the total resection group (11.3±2.5) mmHg (P<0.001). There were interaction effects between groups and time in regards to the left ventricular end-diastolic diameter ( LVEDD ), left ventricular ejection fraction ( LVEF ) and Tei index, as well as the strain rate of mitral annulus and left ventricular wall of interventricular septum of the preservation group and the total resection group (all P<0.05). LVEDD and LVEF of patients in the preservation group at 3rd month after operation were (44.7±4.0) mm and (45.5±4.2) mm, and at 6th months were (56.5±4.9)% and (58.8±5.0)%, respectively, all larger than (42.7±3.6) mm and (42.7±3.6) mm, (54.5±4.6)% and (56.3±4.8)% of the total resection group. The measured value of LVESD in the preservation group at 3rd month after surgery was (32.6±3.2) mm, which was greater than that in the total resection group (31.2±3.4) mm (P<0.05). The Tei index of patients in the preservation group at 3rd and 6th months after surgery were 1.0±0.2 and 0.8±0.2, respectively, which were lower than those in the total resection group 1.2±0.3 and 0.9±0.2 (all P<0.05). Conclusion: Preserving the subvalvular structure during mitral valve replacement surgery can better improve the patient's left ventricular function and left ventricular systolic capacity.

[Analysis of occurrence and treatment of perioperative complete atrioventricular block by transcatheter aortic valve implantation]

Objective: To retrospectively analyze the occurrence and treatment of perioperative complete atrioventricular block (CAVB) by transcatheter aortic valve implantation (TAVI). Methods: A total of 65 patients who underwent TAVI via femoral artery in the Heart Center of Henan People's Hospital from October 2017 to May 2021 were enrolled. Perioperative data of patients were recorded. The patients were divided into two groups according to whether complete atrioventricular block was occurred during TAVI: complete atrioventricular block group (Group CAVB) and non-complete atrioventricular block group (Group NCAVB). Multivariate logistic regression model was used to analyze the risk factors of complete atrioventricular block during transcatheter aortic valve implantation. The incidence of perioperative complications were recorded. Results: The patients age was (69.1±7.3) years old. and there were 35 males and 30 femals. There were 15 patients in group CAVB with complete atrioventricular block and 50 patients in group NCAVB. Multivariate analysis showed that preoperative right bundle branch block [OR (95%CI) vs 3.325 (2.132-13.061), P=0.005] and severe aortic valve calcification [OR (95%CI) vs 1.271 (1.052-3.326), P=0.030] were independent correlative factors for CAVB during TAVI perioperative period. The implantation rate of permanent pacemaker in group CAVB was 73.3% (11 cases), which was higher than 6.0% (3 cases) in group NCAVB (P<0.001). Conclusions: It indicated that preoperative right bundle branch block and severe aortic valve calcification are correlative factors for complete atrioventricular block for TAVI. The implantation rate of permanent pacemaker in complete atrioventricular block group increased significantly.

Circular RNA hsa_circ_0008039 promotes proliferation, migration and invasion of breast cancer cells through upregulating CBX4 via sponging miR-515-5p

OBJECTIVE

Breast cancer (BC) is the second most frequent malignancy worldwide. Hsa_circ_0008039 exerts the carcinogenic factors in BC. However, the pathogenesis of hsa_circ_0008039 involved in BC is still unclear.

PATIENTS AND METHODS

The expression levels of hsa_circ_0008039, microRNA-515-5p (miR-515-5p) and chromobox homolog 4 (CBX4) in BC tissues and cells were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Cell proliferation, migration and invasion were assessed by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) and transwell assays, severally. The binding relationship among hsa_circ_0008039, miR-515-5p and CBX4 was predicted by starBase, then verified by the dual-luciferase reporter assay and immunoprecipitation (RIP) assay. The interaction between hsa_circ_0008039 and miR-515-5p was confirmed by RNA pull-down assay. The protein level of CBX4 was detected by Western blot assay. The biological role of hsa_circ_0008039 was detected by xenograft tumor model in vivo.

RESULTS

Hsa_circ_0008039 was upregulated in BC tissues and cells, and expedited proliferation, migration and invasion of BC cells. MiR-515-5p was downregulated in BC tissues and cells and worked as a target of hsa_circ_0008039. CBX4 was highly expressed in BC tissues and cells, and contributed to proliferation, migration and invasion of BC cells. Hsa_circ_0008039 enhanced CBX4 expression by competitively binding to miR-515-5p, thereby promoting BC development. Hsa_circ_0008039 knockdown repressed BC tumor growth in vivo.

CONCLUSIONS

These findings implicated that hsa_circ_0008039 contributed to proliferation, migration and invasion in vitro and promoted tumor growth in vivo by miR-515-5p/CBX4 axis in BC, suggesting a potential therapeutic strategy for BC treatment.

Modeling and improvement of a low-frequency micro-accelerometer

A sensitivity- and resolution-improving method for a low-frequency micro-vibration accelerometer is presented in this paper. A sensitivity model of the measurement system is derived and established. The key parameters that limit the sensitivity and the resolution of the accelerometer were identified through the sensitivity coefficient analysis method. The structural parameters and the signal process method were then optimized. Experimental results show that the sensitivity of the accelerometer has improved from 1.10 V/(m/s²) to 19.21 V/(m/s²), and the resolution has improved from 1.47 mm/s² to 0.21 mm/s². The lowest working frequency range has expanded from 1 Hz to 0.7 Hz. The presented method is effective and cheap and can be applied to other sensors.

[Clinical study on preserving right gastroepiploic vein during laparoscopic right hemicolectomy]

Objective: The operative approach and steps of laparoscopic right hemicolon cancer radical resection have been standardlized and professional consensus has been reached. However, some detailed issues such as the handling of Henle's trunk and whether to preserve the right gastroepiploic vein (RGEV) still remain controversial. This study investigates the safety, feasibility, short- and long-term outcomes of preserving RGEV during laparoscopic right hemicolectomy. Methods: A retrospective cohort study was carried out. Clinical data of 92 patients undergoing laparoscopic right hemicolectomy in Taizhou People's Hospital from March 2016 to May 2018 were retrospectively analyzed. All the patients were treated with complete mesocolon resection (CME) and had complete postoperative pathological data and follow-up data. Based on the tumor location, 49 patients preserved RGEV (preservation group) and 43 did not (non-preservation group). Pathological data, postoperative complications, short- and long-term outcomes were compared between the two groups. Results: There were no significant differences in baseline data between the two groups (all P>0.05). No significant differences were found in operation time, intraoperative blood loss, unplanned reoperation, anastomotic leak, number of harvested lymph nodes, number of metastatic lymph node, and time to food intake after surgery between two groups (all P>0.05). Compared with non-preservation group, the preservation group had faster recovery of anal gas passage after operation [(3.1±1.0) days vs. (4.0±1.7) days, t=-2.787, P=0.007], shorter length of hospitalization [(11.5±1.5) days vs. (15.0±7.9) days, t=-2.823, P=0.007], and reduced the hospitalization expenses [(46 000±5000) yuan to (57 000±33 000) yuan, t=-2.076, P=0.044]. No postoperative gastroparesis (PGS) occurred in the preservation group, while 6 cases in the non-preservation group developed gastroparesis during perioperative period (P<0.05). The median time of follow-up time was 31.8 (5.2-43.7) months. The overall survival time of the preservation group and non-preservation group was (35.4±1.8) months and (37.6±1.7) months, respectively without significant difference (P=0.336); the disease-free survival was (32.0±2.2) months and (35.5±2.0) months, respectively without significant difference as well (P=0.201). Conclusions: Dissection of the Henle's truck and preservation of RGEV is safe and feasible during laparoscopic right hemicolectomy, which can significantly reduce the incidence of postoperative gastroparesis, shorten the recovery time of postoperative intestinal function and hospitalization, and decrease the cost of hospitalization. The efficacy of RGEV preservation is similar to non-preservation of RGEV.

Bioinformatic analysis of the prognostic value of ZNF860 in recurrence-free survival and its potential regulative network in gastric cancer

OBJECTIVE

In this study, we aimed to investigate the expression profile of C2H2 zinc finger (ZNF) 860 (ZNF860) in gastric cancer (GC), its prognostic significance and its potential regulatory network in GC.

PATIENTS AND METHODS

The level-3 data in the Cancer Genome Atlas-Stomach Adenocarcinoma (TCGA-STAD) was acquired for a secondary analysis, in which clinicopathological, genetic and survival data from 415 GC patients were collected.

RESULTS

The gastric cancerous tissues had significantly upregulated ZNF860 expression. In univariate analysis, male patients, no responses to primary therapy, with male patients and high ZNF860 RNA expression were associated with unfavorable RFS in early GC (stage I/II). Multivariate analysis showed that high ZNF860 RNA expression was independently associated with shorter recurrence-free survival (RFS) in patients with early GC (HR: 5.289, 95%CI: 1.839-15.214, p=0.002). Among 413 cases of GC tumors with copy number alteration (CNA) data available, 35 cases (8.5%) had DNA amplification (+1/+2), while 121 cases (29.3%) had DNA copy loss. ZNF860 amplification was associated with significantly elevated ZNF860 expression. In comparison, DNA copy loss did not necessarily result in ZNF860 downregulation. The methylation of 5 CpG sites in ZNF860 gene (cg24264962, cg24391989, cg10702818, cg15840985, and cg25692785) was negatively correlated with ZNF860 expression. Six genes (OSBPL10, FAM208A, TOPBP1, SPTY2D1, NAB1, and CMTM6) were positively co-expressed with ZNF860, suggesting that ZNF860 probably acts as a transcription enhancer in GC.

CONCLUSIONS

ZNF860 RNA upregulation was an independent prognostic indicator in terms of RFS in stage I/II GC. DNA CNAs and methylation alterations might collaboratively regulate ZNF860 expression.

Ulinastatin protects rats with myocardial infarction by activating Nrf2/NOS pathway

OBJECTIVE

The aim of the study was to explore the pharmacological role of ulinastatin in rats with myocardium infarction (MI) and its underlying mechanism.

MATERIALS AND METHODS

Rats were randomly assigned into sham group, MI group, and ulinastatin group, with 8 rats in each group. MI model in rats was constructed and specific drug administrations were performed in each group. Electrocardiogram and hemodynamics were detected before and after animal procedures. Myocardium function in rats was accessed by determining serum levels of creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH). Hematoxylin and eosin (HE) staining was performed to detect the infarct area in rat myocardium. Terminal Deoxynucleotidyl Transferase dUTP Nick-end Labeling (TUNEL) assay was conducted to calculate the ratio of apoptotic cells in rat myocardium. Subsequently, relative oxidative stress indicators in rats were accessed, including total antioxidant capacity (T-AOC), catalase (CAT), glutathione (GSH), Superoxide Dismutase (SOD), malondialdehyde (MDA), and reactive oxygen species (ROS). Western blot was conducted to detect protein levels of nuclear factor E2-related factor 2 (Nrf2), Nuclear Factor κB (NF-Κb), heme oxygenase-1 (HO-1), and NAD(P)H:quinone oxidoreductase 1 (NQO1) in rat myocardium.

RESULTS

No significant differences in heart rate, the voltage of the QRS wave and Q-T interval were observed among rats in sham group, MI group, and ulinastatin group prior to the animal procedures. However, at the end of the animal procedures, rats in ulinastatin group showed higher heart rate and voltage of QRS wave, as well as shorter Q-T interval than those in MI group. Rats in ulinastatin group presented lower serum levels of CK-MB and LDH compared with those in MI group, whereas they did not return to baseline. Rats in ulinastatin group showed higher levels of LVSP, dP/dtmax, LVEDP, and -dP/dtmax than those in MI group. Larger infarct area was observed in MI group compared with that of sham group, whereas ulinastatin treatment remarkably reduced the infarct area. HE staining showed remarkable pathological lesions in MI rats, whereas ulinastatin group showed milder lesions in rat myocardium. TUNEL assay showed fewer TUNEL-positive cells in ulinastatin group than those of MI group. Levels of T-AOC, CAT, GSH, and SOD were remarkably higher in myocardium homogenate of MI group than sham group, whereas ulinastatin treatment significantly decreased these levels. Ulinastatin group showed less ROS accumulation and decreased MDA level in rats than those of MI group. Ulinastatin treatment upregulated Nrf2, HO-1, and NQO1, whereas downregulated NF-κB expression.

CONCLUSIONS

Ulinastatin protects MI rats by inhibiting inflammatory response through activating Nrf2/NOS pathway.

[Predictive value of cervical length measured by transvaginal ultrasound during the second and the third trimester of pregnancy for preterm birth in twin pregnancies]

Objective: To investigate the predictive value of cervical length (CL) measured by transvaginal ultrasound for preterm birth <32 weeks, <34 weeks in twin pregnancies in the second and the third trimester of pregnancy. Methods: A total of 490 twin pregnant women with CL measured by transvaginal ultrasound during the second trimester of pregnancy (20-24 weeks) and the third trimester of pregnancy (28-32 weeks) delivered in Peking University Third Hospital, and Tongzhou Maternal and Child Health Hospital from January 2014 to December 2017 were collected, and 161 cases out of which were measured by CL during both the second trimester and the third trimester of pregnancy. Based on the measured gestational weeks, 427 cases were in the second trimester group and 224 cases in the third trimester group. The predictive value of CL for preterm birth was evaluated by calculating the optimal cut-off point with sensitivity and specificity. Logistic regression analysis was used to assess the relationship between CL and preterm birth after adjusting for confounding factors (age of pregnant women, chorionic status, mulipara, assisted reproductive pregnancy and pre-pregnancy body mass index). Results: (1) The median CL of pregnant women in the second trimester group and the third trimester group were 36 mm (33-40 mm) and 28 mm (18-33 mm) respectively. In the second trimester group, 151 cases (35.4%, 151/427) were preterm birth and 276 cases (64.6%, 276/427) were full-term birth; the median CL of preterm and full-term pregnant women were 34 mm (30-37 mm) and 37 mm (34-40 mm), respectively, with significant difference (P<0.01). In the third trimester group, 100 cases (44.6%, 100/224) were preterm birth and 124 cases (55.4%, 124/224) were full-term birth; the median CL of preterm and full-term pregnant women were 22 mm (15-30 mm) and 31 mm (23-34 mm), respectively, with significant difference (P<0.01). (2) Prediction of preterm birth <32 weeks and <34 weeks was performed with CL in the second trimester group. The area under the receiver-operating characteristics curve were 0.78 (95%CI: 0.70-0.86) and 0.71 (95%CI: 0.64-0.79), respectively. The optimal cut-off points were 36.5 mm and 33.5 mm, respectively. After adjusting for confounding factors, CL was inversely associated with preterm birth <32 weeks and <34 weeks of gestation. (3) Prediction of preterm birth <32 weeks and <34 weeks were performed with CL in the third trimester group. The area under the receiver-operating characteristics curve were 0.86 (0.75-0.96) and 0.75 (0.67-0.84), respectively. The optimal cut-off points were 17.5 mm and 18.5 mm, respectively. After adjusting for confounding factors, CL was inversely associated with preterm birth at <32 weeks and <34 weeks of gestation. Conclusions: CL measured by transvaginal ultrasound in the second and the third trimester is a good predictor for preterm birth of twin pregnancy. CL≤36.5 mm and ≤33.5 mm at 20-24 weeks of gestation could predict preterm birth <32 weeks and <34 weeks respectively. CL≤17.5 mm and ≤18.5 mm at 28-32 weeks of gestation could predict preterm birth <32 weeks and <34 weeks respectively.

[Regulation of Ruxolitinib on matrix metalloproteinase in JAK2V617F positive myeloroliferative neoplasms cells]

Objective: To investigate the regulation of JAK2 tyrosine kinase inhibitor ruxolitinib on extracellular matrix metalloproteinase (MMP in JAK2V617F positive myeloproliferative neoplasms (MPN) cells. Methods: ①Forty cases of newly diagnosed JAK2V617F positive MPN patients and 15 healthy volunteers as control in Baoding No.1 Hospital between January 2012 and December 2015 were enrolled in this study. JAK2V617F/JAK2 ratio was detected by real-time-PCR; the expression levels of phosphorylation protein tyrosine kinase 2 (p-JAK2) , MMP-2 and MMP-9 in pathological tissues of bone marrow were detected by immunohistochemistry. The bone marrow cells of JAK2V617F positive MPN patients were treated with ruxolitinib, then the migration ability and MMP-2, MMP-9 gene and protein expression levels were detected. ②The human erythroleukemia cell line HEL cells were treated with different concentrations of ruxolitinib (0, 50, 100, 250, 500, 1 000 nmol/L) . The cell viability was detected by CCK-8 test; cell migration ability was tested by transwell chambers. The mRNA expression levels of JAK2, MMP-2 and MMP-9 were detected by real-time-PCR. The protein expression levels of p-JAK2, MMP-2 and MMP-9 were detected by Western blot. Results: ①The expression levels of p-JAK2, MMP-2 and MMP-9 in the newly diagnosed group were significantly higher than control group respectively [ (78.56±24.55) % vs (41.59±17.29) %, P<0.05; (48.25±18.74) % vs (22.79±13.89) %, P<0.05; (53.29±19.28) % vs (15.56±14.96) %, P<0.05]. Spearman correlation analysis showed the positive correlation of MMP-2 and MMP-9 protein expression levels with JAK2V617F mutation (r=0.526, P=0.001; r=0.543, P=0.001) . ②The proliferation of HEL cells was inhibited by different concentrations of ruxolitinib in time and dose dependent manner. ③Cell migration test showed the number of cells leaked to the low chamber in MPN patients bone marrow cells and HEL cells treated with 5 nmol/L of ruxolitinib group were significantly lower than that without ruxolitinib treatment after 24 h [ (154.7±27.5) vs (320.3±67.3) , t=13.47, P<0.05; (70.7±10.5) vs (135.3±16.7) , t=13.89, P<0.05]. The mRNA and protein expression levels of JAK2, MMP-2 and MMP-9 decreased with the increased concentration of ruxolitinib. Conclusion: Ruxolitinib inhibits MPN cell migration and expression of MMP-2 and MMP-9 via JAK2 signal pathway.

[Effect of miR-19b on the proliferation and apoptosis of P19CL6 cells during the late-stage of cardiac differentiation]

Objective: To explore the effect of miR-19b on the function of P19CL6 cells and its molecular mechanism. Methods: Overexpression of miR-19b was carried out by transfecting miR-19b plasmid into the P19CL6 cells. MTT assay and flow cytometry were used to determine cell growth and apoptosis, respectively. Western blot was used to detect the expression level of Sox6 in P19CL6 cells. ELISA assay was used to detect the expression levels of apoptosis-related genes (Bax, Bcl-2) in P19CL6 cells at late-stage cardiac differentiation. Further online software TargetScan was used to predict the target genes of miR-19b and verified by dual luciferase reporter assay. Results: Our data showed that overexpression of miR-19b in P19CL6 cells significantly increased the cell growth rates and the apoptosis inhibition rates. The ratio of apoptosis-related proteins (Bax/Bcl-2) was significantly reduced. Results from the TargetScan and dual luciferase reporter showed that Sox6 is the direct target of miR-19b. Conclusions: We conclude that miR-19b might promote cell proliferation and inhibits cell apoptosis during the late-stage of cardiac differentiation by targeting Sox6 expression.

MiR-365 participates in coronary atherosclerosis through regulating IL-6

OBJECTIVE

This study aims to investigate the role and mechanism of miR-365 in the coronary atherosclerosis (AS).

PATIENTS AND METHODS

Blood were collected from AS patients and healthy people, coronary plaque and adjacent arterial tissue were collected from AS patients. QRT-PCR method was used to detect expressions of miR-365 and IL-6 in coronary plaque, blood monocytes, and serum. Western blot was applied to detect IL-6 protein expression in coronary plaque and blood monocytes, and ELISA was used to detect IL-6 protein expression in serum.

RESULTS

Compared with the normal group, IL-6 expression was significantly increased in coronary plaque, blood monocytes, and serum both in mRNA level and in protein level, while miR-365 expression was significantly decreased (p < 0.05).

CONCLUSIONS

IL-6 expression was significantly up-regulated in coronary plaque, blood monocytes, and serum, whereas miR-365 expression was down-regulated. MiR-365 may regulate the pathogenesis and immune response in AS through targeting IL-6.

Process and Microstructure to Achieve Ultra-high Dielectric Constant in Ceramic-Polymer Composites

Influences of process conditions on microstructure and dielectric properties of ceramic-polymer composites are systematically studied using CaCu₃Ti₄O₁₂ (CCTO) as filler and P(VDF-TrFE) 55/45 mol.% copolymer as the matrix by combining solution-cast and hot-pressing processes. It is found that the dielectric constant of the composites can be significantly enhanced-up to about 10 times - by using proper processing conditions. The dielectric constant of the composites can reach more than 1,000 over a wide temperature range with a low loss (tan δ ~ 10^-1). It is concluded that besides the dense structure of composites, the uniform distribution of the CCTO particles in the matrix plays a key role on the dielectric enhancement. Due to the influence of the CCTO on the microstructure of the polymer matrix, the composites exhibit a weaker temperature dependence of the dielectric constant than the polymer matrix. Based on the results, it is also found that the loss of the composites at low temperatures, including room temperature, is determined by the real dielectric relaxation processes including the relaxation process induced by the mixing.

[Feasibility of retrograde approach for percutaneous closure of ventricular septal defect under solely guidance of transesophageal echocardiography]

OBJECTIVE

To evaluate the feasibility of retrograde transcatheter closure of ventricular septal defects (VSD) under trans-esophageal echocardiography (TEE).

METHODS

Twelve patients with VSD, with 4 residual shunt, treated by transcatheter VSD closure under solely guidance of TEE were summarized. Mean age, body weight and average diameter of VSD in 12 cases were (11.58±6.57) years, (31.85±13.28) kg, (5.50±2.20) mm, respectively. All patients were treated by retrograde transcatheter closure under solely guidance of TEE. The post-operative efficiency was estimated by TEE immediately. Patients were followed up by echocardiography, X-ray examination and electrocardiogram at 24 hours, 1, 3 and 6 months after the procedures.

RESULTS

All 12 patients were treated successfully under solely guidance of TEE. The diameter of devices were 5-14 mm. There were 1 case with trivial residual shunt after the procedures immediately. No patients suffered from residual shunt, occluder malposition, peripheral vascular injury and pericardial effusion during the follow-up.

CONCLUSION

Percutaneous transcatheter closure of VSD completely guided by TEE is safe and effective. This method could avoid the radiation and contrast media reaction, and also could simplify the procedure.

Correlation of serum PCSK9 in CHD patients with the severity of coronary arterial lesions

OBJECTIVE

The present study aims to investigate the correlation between serum level of proprotein convertase subtilisin/kexin type 9 (PCSK9) and the severity of coronary arterial lesion in patients with coronary heart disease (CHD).

PATIENTS AND METHODS

Between August 2010 and January 2015, 126 CHD patients and 70 patients with coronary arterial stenosis < 50% (controls) were included in the present study. Serum PCSK9 level was determined using ELISA. Demographic characteristics, relevant clinical data and biochemical data were collected from all patients, and their relationship with PCSK9 was analyzed to evaluate the correlation of PCSK9 expression with the severity of coronary artery disease (CAD).

RESULTS

Concentrations of total cholesterol (TC) and fasting blood sugar (FBS) were significantly higher in CHD patients than in controls (p < 0.05). No significant differences were observed in gender, age, body mass index (BMI), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), family history, smoking history and history of hypertension between groups (p > 0.05). Serum PCSK9 levels in the CHD group were significantly higher than those in the control group [(96.4 ± 33.2) ng/mL vs. (81.8 ± 27.6) ng/mL, p < 0.05]. Compared with those of patients with single-vessel or double-vessel disease, PCSK9 levels were significantly elevated in patients with multi-vessel disease (p < 0.05). The Gensini score of the CHD group was significantly lower than that of the control group (11.4 ± 10.5 vs. 37.3 ± 10.3, p < 0.05). The Gensini score of patients with multi-vessel disease was significantly higher compared with patients of single-vessel  or double-vessel disease (p < 0.05). Correlation analysis revealed that PCSK9 was positively correlated with many clinical parameters, including age, BMI, TC, TG, systolic blood pressure, FBS, Gensini score and LDL-C (p < 0.05). However, PCSK9 was not correlated with either gender ratio or diastolic blood pressure (p > 0.05).

CONCLUSIONS

Serum PCSK9 level is significantly elevated in CHD patients and its variation is correlated with the severity of CAD.

Stimulation of α1-adrenoceptors facilitates GABAergic transmission onto pyramidal neurons in the medial prefrontal cortex

Whereas activation of α1-adrenoceptors (α1-ARs) modulates glutamatergic transmission, the roles of α1-ARs in GABAergic transmission in the medial prefrontal cortex (mPFC) are elusive. Here, we examined the effects of the α1-AR agonist phenylephrine (Phe) on GABAergic transmission onto pyramidal neurons in the deep layers of the mPFC. We found that bath application of Phe dose-dependently increased the amplitude of evoked IPSCs (eIPSCs). Phe increased the frequency but not the amplitude of miniature IPSCs (mIPSCs). Ca(2+) influx through T-type voltage-gated calcium channels is required for Phe-induced increases in GABA release. Phe increases GABA release probability and the number of releasable vesicles. Phe depolarizes the fast-spiking (FS) interneurons without effects on the firing rate of action potentials (APs) of interneurons. Phe-induced depolarization is independent of extracellular Na(+), Ca(2+) and T-type calcium channels, but requires inward rectifier K(+) channels (Kirs). The present study demonstrates that Phe enhances GABAergic transmission onto mPFC pyramidal neurons through inhibiting interneurons Kirs, which further depolarizes interneurons leading to increase in Ca(2+) influx via T-type calcium channels. Our results may provide a cellular and molecular mechanism that helps explain α1-AR-induced PFC dysfunction.

GABAB1 and GABAB2 receptor subunits co-expressed in cultured human RPE cells regulate intracellular Ca2+ via Gi/o-protein and phospholipase C pathways

GABAB receptors associate with Gi/o-proteins that regulate voltage-gated Ca(2+) channels and thus the intracellular Ca(2+) concentration ([Ca(2+)]i), there is also reported cross-regulation of phospholipase C. These associations have been studied extensively in the brain and also shown to occur in non-neural cells (e.g. human airway smooth muscle). More recently GABAB receptors have been observed in chick retinal pigment epithelium (RPE). The aims were to investigate whether the GABAB receptor subunits, GABAB1 and GABAB2, are co-expressed in cultured human RPE cells, and then determine if the GABAB receptor similarly regulates the [Ca(2+)]i of RPE cells and if phospholipase C is involved. Human RPE cells were cultured from five donor eye cups. Evidence for GABAB1 and GABAB2 mRNAs and proteins in the RPE cell cultures was investigated using real time polymerase chain reaction, western blots and immunofluorescence. The effects of the GABAB receptor agonist baclofen, antagonist CGP46381, a Gi/o-protein inhibitor pertussis toxin, and the phospholipase C inhibitor U73122 on [Ca(2+)]i in cultured human RPE were demonstrated using Fluo-3. Both GABAB1 and GABAB2 mRNA and protein were identified in cell cultures of human RPE; antibody staining was co-localized to the cell membrane and cytoplasm. One-hundred micromolars of baclofen caused a transient increase in the [Ca(2+)]i of RPE cells regardless of whether Ca(2+) was added to the buffer. Baclofen-induced increases in the [Ca(2+)]i were attenuated by pre-treatment with CGP46381, pertussis toxin, and U73122. GABAB1 and GABAB2 are co-expressed in cell cultures of human RPE. GABAB receptors in RPE regulate the [Ca(2+)]i via a Gi/o-protein and phospholipase C pathway.

Magnetostrictive particle based biosensors for in situ and real-time detection of pathogens in water

Biosensors for in situ detection of pathogenic bacteria in liquid are developed using magnetostrictive particles (MSP) as the sensor platform. The sensing elements used are phage E2 against Salmonella typhimurium, monoclonal antibody against Listeria monocytogenes, polyclonal antibody against Escherichia coli, and polyclonal antibody against Staphylococcus aureus, respectively. These biosensors were characterized in cultures with different populations ranging from 5 × 10(1) to 5 × 10(8)  cfu/mL. It is found that the MSP-based biosensors work well in water and have a rapid response with a response time in minutes, which makes the MSP-based sensors suitable for in situ and real-time detection of pathogenic bacteria in liquid. The experimental results show that all MSP-phage and MSP-antibody biosensors in size of 1.0 mm × 0.3 mm × 15 µm exhibit a detection limit better than 100 cfu/mL. Based on the Hill plot, it is concluded that each bacterial cell is bound onto the sensor surface through about four-to-five sites. When the cultures with low population (<10(6)  cfu/mL) are tested, both MSP-phage and MSP-antibody sensors exhibit the similar response. However, the phage-MSP sensors exhibit a higher capability in the capture of target bacterial cell.

Effect of oxygen stoichiometry in LuFe2O(4-δ) and its microstructure observed by aberration-corrected transmission electron microscopy

A series of oxygen deficient LuFe(2)O(4-δ) materials have been prepared under a controlled oxygen partial-pressure atmosphere. Measurements of magnetization reveal that the increase of oxygen deficiencies could evidently depress the ferrimagnetic phase transition temperature (T(N)). In additional to the well-known charge ordering within the (11(-)0) crystal plane, a visible structural modulation with q = (0,1/4.2,7/8) commonly appears on the (100) plane in the oxygen deficient samples. An aberration-corrected transmission electron microscopy study on the oxygen deficient samples demonstrates the presence of oxygen vacancies and local structural distortion. The atomic structural features in correlation with the structural modulation, distortion of the FeO(5) polyhedron and the (001) twinning domains have been also examined.

Multishell intermetallic onions by symmetrical configuration of ordered domains

Ordered domains are utilized to construct new nanostructures, i.e., multishell intermetallic onions, which are formed by symmetrical configuration of ordered domains. Through density-functional theory calculations, we have shown that the energy penalties for introducing antiphase boundaries into the nanoparticles are small in some alloy systems compared to typical surface energies, making it feasible to prepare intermetallic onions by tuning surface energies. The unique surface atomic arrangements would provide opportunities for developing novel materials like efficient catalysts.

Direct subangstrom measurement of surfaces of oxide particles

Using aberration-corrected transmission electron microscopy combined with first-principles calculations, we show that the surface structure of Co3O4, a typical complex oxide, can be directly imaged and quantitatively analyzed at the subangstrom scale. The atomic positions of both light oxygen and heavier cobalt within the surface layers have been measured to an accuracy of several picometers. The surface electronic structure analysis suggests a polarity compensation model based on the electronic polarizability of surface ions.

An all-organic composite actuator material with a high dielectric constant

Electroactive polymers (EAPs) can behave as actuators, changing their shape in response to electrical stimulation. EAPs that are controlled by external electric fields--referred to here as field-type EAPs--include ferroelectric polymers, electrostrictive polymers, dielectric elastomers and liquid crystal polymers. Field-type EAPs can exhibit fast response speeds, low hysteresis and strain levels far above those of traditional piezoelectric materials, with elastic energy densities even higher than those of piezoceramics. However, these polymers also require a high field (>70 V micro m(-1)) to generate such high elastic energy densities (>0.1 J cm(-3); refs 4, 5, 9, 10). Here we report a new class of all-organic field-type EAP composites, which can exhibit high elastic energy densities induced by an electric field of only 13 V micro m(-1). The composites are fabricated from an organic filler material possessing very high dielectric constant dispersed in an electrostrictive polymer matrix. The composites can exhibit high net dielectric constants while retaining the flexibility of the matrix. These all-organic actuators could find applications as artificial muscles, 'smart skins' for drag reduction, and in microfluidic systems for drug delivery.

[Separation and determination of glibenclamide in xiaotangling tablets by micellar electrokinetic capillary chromatography]

A high performance capillary electrophoresis method has been developed for separation and quantitative analysis of glibenclamide in Xiaotangling tablets. Electrophoretic conditions were as follows: micellar electrokinetic capillary chromatography (MECC) mode, trimethoprimum as internal standard, uncoated fused silica capillary (34.8 cm/39.5 cm(effective/total length), 50 microns i.d.), 25 mmol/L borax-30 mmol/L SDS(pH 9.0), applied voltage 17 kV, (+)-->(-), temperature 28 degrees C, detection wavelength 228 nm, pressure injection 68.95 kPa.s. Glibenclamide was separated successfully from other components within 14 minutes under the optimum conditions, and the relative peak area of glibenclamide increased linearly with the increase of its concentration within the range of 25 mg/L-275 mg/L. The recovery was (100.6 +/- 1.4)%. The method is simple, rapid and well reproducible, and can be used as a reliable tool for the quality control of Chinese traditional medicine containing glibenclamide.

[Separation and determination of baicalin in prescriptions containing Scutellaria baicalensis Georgi by HPCE]

Qingkailing Oral Tonic and Shuanghuanglian Oral Tonic are two kinds of complex formlae of Chinese traditional patent medicine, and both contain Scutellaria baicalensis Georgi. Baicalin is referred to the main active component with functions of dispelling wind-heat to reduce fever and detoxicating, and takes effect on uppering respiratory tract infection and tonsillities. In this work a high performance capillary electrophoresis (HPCE) method was established for separation and quantitative analysis of baicalin in prescriptions containing Scutellaria baicalensis Georgi, based on the mode of capillary zone electrophoresis. Electrophoretic conditions are as follows: uncoated fused silica capillary (34.8/39.5 cm x 50 microns i.d.), 40 mmol/L borax buffer(pH 9.0), applied voltage 17 kV, polarity anode (inlet) to cathode (outlet), temperature 25 degrees C, detection wavelength 285 nm, injection 68.95 kPa x s. Under the optimum conditions, baicalin was separated successfully from other components within 15 minutes. The relative peak area of baicalin increased linearly with the increase of its concentration in the range of 10-640 mg/L. The recoveries were (100.31 +/- 1.98)% for Qingkailing Oral Tonic and (100.60 +/- 2.36)% for Shuanghuanglian Oral Tonic. The analytical results demonstrate the method is simple, rapid and well reproducible, and can be used as a reliable tool for the quality control of Chinese traditional medicines containing Scutellaria baicalensis Georgi.

Effect of high energy electron irradiation on the electromechanical properties of poly (vinylidene fluoride-trifluorethylene) 50/50 and 65/35 copolymers

High energy electron irradiation with a broad range dosage was carried out on poly(vinylidene fluoride trifluorethylene) copolymer 65/35 mol% and 50/50 mol% films at different temperatures from room temperature to a temperature close to the melt temperature. The effect of irradiation on the properties of the films, such as electric field-induced strain, dielectric and polarisation behaviors, and mechanical modulus, is presented. The irradiated films can exhibit a very large electric field-induced strain, more than 4.5% longitudinal strain, and 3% transverse strain. The transverse strain of the stretched film can compare with the longitudinal strain; that of the unstretched film is much smaller than the longitudinal strain. With regard to the dielectric and polarization behaviors, we found that irradiation changes the copolymer from a typical ferroelectric to a relaxor ferroelectric in which the behavior of microregions under the electric field plays the key role. Between the two copolymers studied, we found that the 65/35 copolymer is preferred for both longitudinal and transverse strain generation. A model is proposed to explain the experimental results that the amplitude of the charge electrostrictive coefficient (Q) increases with decreasing crystallinity.

[Determination of baicalin and chlorogenic acid in yinhuang granule by capillary electrophoresis]

Yinhuang Granule is a kind of complex formulae made up of extract of Flos lonicerae and that of Radix scutellariae, of the fuctions of dispelling wind-heat to reduce fever, detoxicating, relieving inflammation, promoting urination and tranquilizimg the mind and can be applied to upper respiratory tract infection and tonsillitis. Baicalin and chlorogenic acid are referred to main effective components of it. In this paper, the separation and determination of baicalin and chlorogenic acid in Yinhuang Granule by capillary electrophoresis is described. The experimental conditions are stated as follow: separation column: bare fused-sillica capillary (50 microns i.d., 370 microns o.d., total length 47 cm, 40 cm from the inlet to UV detector); electrolyte: 25 mmol/L borax, pH 8.5; detection wavelength: 310 nm; sampling: 17 kPa.s; running voltage: 25 kV, polarity from anode (inlet) to cathode (outlelt); temperature: 25 degrees C; internal standard: p-nitrobenzoic acid. The linear ranges of determination for baicalin and chlorogenic acid were 160-960 mg/L(r = 0.9993, RSD = 1.76%-2.33%) and 80-960 mg/L(r = 0.9989, RSD = 1.07%-2.51%), respectively. The recoveries of baicalin and chlorogenic acid were (102.09 + 1.74)% (RSD = 1.71%, n = 6) and (99.81 + 3.11)% (RSD = 3.12%, n = 6). The method is simple, fast and accurate. It can be used for the quality control of Yinhuang Granule and its related Chinese medicines.

Baseband integrated acousto-optic frequency shifter/modulator module for fiber optic at 1.3 mum

A baseband integrated acoustooptic (AO) frequency shifter/modulator module that consists of a pair of titanium-indiffused proton-exchanged (TIPE) waveguide lenses and a pair of cascaded guided-wave AO Bragg cells has been realized in a Y-cut LiNbO(3) waveguide substrate 0.1 cmx1.0 cmx2.0 cm in size. A device module operating at the optical wavelength of 1.3 mum has provided a -3-dB tunable bandwidth of 120 MHz at baseband. The frequency-shifted or -modulated light propagates in a fixed direction, irrespective of the magnitude of frequency shift or modulation, and is focused into a spot (FWHM) of 6.2-mum size on the output edge of the waveguide. Accordingly, this optical frequency shifter/module can be directly interfaced with single-mode optical fibers to facilitate applications in fiber optic systems.

The antitumor effects of qigong-emitted external Qi and its influence on the immunologic functions of tumor-bearing mice

By utilizing murine tumor models bearing Ehrlich ascites carcinoma (EAC) and ascitic Sarcoma-180 (S-180), we investigated the in vivo antitumor effects of QEQ or/and the chemotherapeutic agent cyclophosphamide (CY) and their influence on the splenic natural killer (NK) activity, macrophage-mediated tumor cytolysis (MTC) activity and interleukin-2 (IL-2) production level of different groups of TBM. The results demonstrate that Qigong-emitted external Qi (QEQ) has inhibitory effects on tumor growth of tumor-bearing mice (TBM) and enhancing effects on antitumor immunologic functions of the tumor host simultaneously. Moreover, when used in combination with CY, QEQ can not only significantly increase the antitumor efficacy, but also markedly improve the compromised antitumor immunologic functions of the tumor host. Therefore, our findings suggest that in clinical practice of cancer treatment Qigong therapy in combination with conventional therapy (such as chemotherapy) is a treatment regimen worth recommending.

Molecular markers for the agouti coat color locus of the mouse

The agouti (a) coat color locus of the mouse acts within the microenvironment of the hair follicle to control the relative amount and distribution of yellow and black pigment in the coat hairs. Over 18 different mutations with complex dominance relationships have been described at this locus. The lethal yellow (Ay) mutation is the top dominant of this series and is uniquely associated with an endogenous provirus, Emv-15, in three highly inbred strains. However, we report here that it is unlikely that the provirus itself causes the Ay-associated alteration in coat color, since one strain of mice (YBR-Ay/a) lacks the provirus but still retains a yellow coat color. Using single-copy mouse DNA sequences from the regions flanking Emv-15 we have detected three patterns of restriction fragment length polymorphisms (RFLPs) within this region that can be used as molecular markers for different agouti locus alleles: a wild-type agouti (A) pattern, a pattern which generally cosegregates with the nonagouti (a) mutation, and a pattern which is specific to Emv-15. We have used these RFLPs and a panel of 28 recombinant inbred mouse strains to determine the genetic linkage of these sequences with the agouti locus and have found complete concordance between the two (95% confidence limit of 0.00 to 3.79 centimorgans). We have also physically mapped these sequences by in situ hybridization to band H1 of chromosome 2, thus directly confirming previous assignments of the location of the agouti locus.

Isolation of transcribed DNA sequences from chromosome 21 using mouse fetal cDNA

A technique for isolating DNA sequences that are likely to be transcriptionally active in both humans and mice has been developed. This method is based on the screening of a human genomic DNA library with single stranded cDNA prepared from late gestation mouse fetal RNA. Using a human chromosome 21 DNA library, we have isolated and characterized two clones which are entirely composed of single copy human DNA sequences and are 2.7 and 6.7 kilobases in length. The 2.7 kilobase clone is homologous to a transcript found predominantly in nonpolyadenylated human fibroblast RNA. It also shows homology to mouse genomic DNA and recognises several polyadenylated RNAs in mouse testis. This cloned sequence has been mapped by in situ hybridization to the distal third of chromosome 21, the region involved in the causation of Down syndrome.

The mouse IFN-alpha (Ifa) locus: correlation of physical and linkage maps by in situ hybridization

The physical location of the mouse IFN-alpha locus (Ifa) on chromosome 4 was defined by in situ hybridization of a cloned mouse IFN-alpha probe to metaphase spreads in which one chromosome 4 was present as part of a single metacentric chromosome, all other chromosomes being acrocentric. (This approach greatly facilitates analysis and can be used even when it is difficult to obtain good banding). Using unbanded chromosomes, the grains were localized over the chromosome 4 part of the metacentric, in a region 0.61 +/- 0.07 (SD) of the distance from the centromere to the telomere. In Giemsa-banded spreads, the majority of the grains were in the region 4C3----C6. Consideration of these results and of the known linkage maps for mouse and man indicates that the Galt - Aco-1 - Ifa syntenic group spans a distance of approximately 14 cM and suggests that the same group on human 9p will also occupy a similarly sized region, with GALT proximal and IFL distal to the centromere.