Genomic, transcriptomic, and epigenomic analysis of a medicinal snake, Bungarus multicinctus, to provides insights into the origin of Elapidae neurotoxins

The many-banded krait, Bungarus multicinctus, has been recorded as the animal resource of JinQianBaiHuaShe in the Chinese Pharmacopoeia. Characterization of its venoms classified chief phyla of modern animal neurotoxins. However, the evolutionary origin and diversification of its neurotoxins as well as biosynthesis of its active compounds remain largely unknown due to the lack of its high-quality genome. Here, we present the 1.58 Gbp genome of B. multicinctus assembled into 18 chromosomes with contig/scaffold N50 of 7.53 Mbp/149.8 Mbp. Major bungarotoxin-coding genes were clustered within genome by family and found to be associated with ancient local duplications. The truncation of glycosylphosphatidylinositol anchor in the 3'-terminal of a LY6E paralog released modern three-finger toxins (3FTxs) from membrane tethering before the Colubroidea divergence. Subsequent expansion and mutations diversified and recruited these 3FTxs. After the cobra/krait divergence, the modern unit-B of β-bungarotoxin emerged with an extra cysteine residue. A subsequent point substitution in unit-A enabled the β-bungarotoxin covalent linkage. The B. multicinctus gene expression, chromatin topological organization, and histone modification characteristics were featured by transcriptome, proteome, chromatin conformation capture sequencing, and ChIP-seq. The results highlighted that venom production was under a sophisticated regulation. Our findings provide new insights into snake neurotoxin research, meanwhile will facilitate antivenom development, toxin-driven drug discovery and the quality control of JinQianBaiHuaShe.

Trichostatin C attenuates TNFα-induced inflammation in endothelial cells by up-regulating Krüppel-like factor 2 / 药学学报

Krüppel-like transcription factor 2 (KLF2) plays a key regulatory role in endothelial inflammation, thrombosis, angiogenesis and macrophage inflammation and polarization, and up-regulation of KLF2 expression has the potential to prevent and treatment atherosclerosis. In this study, trichostatin C (TSC) was obtained from the secondary metabolites of rice fermentation of Streptomyces sp. CPCC 203909 as a KLF2 up-regulator by using a high throughput screening model based on a KLF2 promoter luciferase reporter assay. TSC significantly inhibited the adhesion of tumor necrosis factor-α (TNFα) induced monocytes (THP-1) to human umbilical vein endothelial cells (HUVECs). Western blot results showed that TSC decreased TNFα induced the protein expression increase of vascular cell adhesion molecule-1 (VCAM-1), and thereby inhibited endothelial inflammation. The results of histone deacetylase (HDAC) overexpression and molecular docking experiments showed that TSC upregulated the expression of KLF2 by inhibiting subtypes of HDAC 4/5/7. In conclusion, this study suggests that TSC up-regulates the expression of KLF2 through inhibiting HDAC 4/5/7 and thus inhibits TNFα induced endothelial inflammation, and it has the potential to prevent and treat atherosclerosis.

Analysis on off-label use of drugs in pediatric guidelines and consensus published by Chinese authors / 中华儿科杂志

Objective: To understand the current situation regarding pediatric off-label use of drugs recommendations in Chinese clinical practice guidelines and to make recommendations for standardized reporting format regarding off-label use of drugs for children. Methods: This cross-sectional study was carried out by systematically searching the databases for Chinese guideline consensus articles published in journals between 2018 and 2020 and extracting recommendations regarding off-label use of drugs from those articles. The essential characteristics of the included guidelines, the ranking of off-label drug types, the order of drug information, the type of off-label drug use, and the percentage of citation studies on which the recommendations were based were analyzed. Results: Among 108 studies that included Chinese off-label guidelines and consensus, 364 recommendations on pediatric off-label use of drugs were included. The Chinese Medical Association published the most, 48 out of the 108 studies (44.4%), and of those 14 studies (13.0%) were on infectious and parasitic diseases. Of the 364 recommendations on off-label use of drugs, the most commonly addressed drugs were 16 recommendations (4.4%) for cyclosporine A, 11 recommendations (3.0%) for methotrexate , and 11 recommendations (3.0%) for fentanyl. The most commonly addressed drug categories were as follows: 68 recommendations (18.6%) were immune system drugs, 66 recommendations (18.1%) were anti-infectives, and 56 recommendations (15.4%) were oncology drugs. The most commonly addressed drug information accounts were as follows: 364 recommendations (100.0%) were indications, 204 recommendations (56.0%) were dosages, and 198 recommendations (54.4%) were the route of administration. Based on the instructions approved by the Chinese Food and Drug Administration, the main forms of the off-label drug were as follows: 175 recommendations (48.1%) were unapproved indications, 127 recommendations (34.9%) were unapproved populations, and 72 recommendations (19.8%) were unapproved ages. Only 129 recommendations (35.4%) were cited, mainly including clinical guidelines (48 studies, 23.4%), reviews (22 studies, 10.7%), and pediatric randomized controlled trials (22 studies, 10.7%). Conclusions: Off-label use of drugs is commonly recommended in pediatric guidelines and consensus documents written by Chinese authors. However, the reporting of the recommendations varies widely, and the quality of the supporting evidence is poor.

Effect of rosmarinicacid on inflammatory factors and immune function for rats with oral ulcers / 医学研究生学报

Objective The pathogenesis of orla ulcer has not been fully and thoroughly studied. This study aimed to investi-gate the effect and mechanism of Rosmarinic acid (RA)on oral ulcer. Methods 60 SD rats were randomly divided into control group,model group,RA groups(20,40,80 mg/kg) and Watermelon Frost group. The control group rats were fed normally and with-out any treatment. The oral ulcer model was established in the other three groups. The oral ulcer model of rat was established by injec-tion of 40% glacial acetic acid on the oral mucosa of cheek in rat. One day after the formation of ulcers,RA(20,40,80 mg/kg) and watermelon frost (200 mg/kg) was administrated. The ulcer area was measured 3,5,7 days after establishing the model. The concen-tration of IL-18 and IL-1β in ulcer tissue was measured by ELISA method and the expression of NLRP3 mRNA was measured by qRT-PCR. Results Compared with the model group, the ulcer area in the RA group and Watermelon Frost group was significantly de-ceased(P<0.05). Compared with the control group,NLRP3,IL-18 and IL-1β in the ulcer tissue was significantly elevated in model group,RA groups (20,40,80 mg/kg) and Watermelon Frost group (P<0.01). NLRP3 expressed lower in RA (40,80 mg/kg) and wa-termelon frost (200 mg/kg) group(5.27 ± 0.53, 3.25 ± 0.46, 4.75 ± 0.51) than in model group(8.71±0.35)( P<0.05). IL-18 expressed lower in RA (40, 80 mg/kg) and watermelon frost (200 mg/kg) group [(174.21±18.21), (110.12±14.23), (142.25±12.61) pg/mL] than in model group [(246.21±26.21) pg/mL](P<0.05). IL-1β expressed lower in RA (40, 80 mg/kg) and watermelon frost(200 mg/kg) group [(94.76±7.26),(81.77±7.80),(90.21±8.71) pg/mL] than in model group [(133.01±11.69) pg/mL](P<0.05). Conclusion RA has some therapeutic effect on oral ulcers,the mechanism may be related to NLRP3.

Research status of src-homology 2 domain-containing protein tyrosine phosphatase 1 in liver diseases / 第二军医大学学报

Protein tyrosine phosphorylation is ubiquitously found in eukaryotic cells, and it is a fundamental regulatory mechanism to be involved in the regulation of cell proliferation, apoptosis, differentiation and migration. Dysregulation of protein tyrosine phosphorylation can influence various liver diseases, such as liver inflammation, liver fibrosis and liver cancer. The src-homology 2 domain-containing protein tyrosine phosphatase 1 (SHP-1), a nonreceptor type protein tyrosine phosphatase, is a key regulator of maintaining protein tyrosine phosphorylation level in vivo. Recently, great progress in the research of SHP-1 in liver diseases has been made, and this review summed up the advances of SHP-1 in liver diseases.

Effects of different target plasma concentrations of propofol on ventricular repolarization in elderly patients / 中华麻醉学杂志

Objective To evaluate the effects of different target plasma concentrations of propofol on ventricular repolarization in elderly patients.Methods Forty-five patients,aged 65-80 yr,weighing 43-85 kg,of American Society of Anesthesiologists physical status Ⅰ or Ⅱ,scheduled for elective surgery under general anesthesia,were divided into 3 groups (n=15 each) using a random number table:propofol at target plasma concentration of 2 μg/ml group (group P1),propofol at target plasma concentration of 3 μg/ml group (group P2) and propofol at target plasma concentration of 4 μg/ml group (group P3).Before induction of anesthesia (T1) and at 5 min after propofol reached the target plasma concentration (T2),12-lead electrocardiogram was recorded,the QT and Tp-e intervals were measured,and the corrected QT (QTc) interval and Tp-e/QT ratio were calculated.Results There were no significant differences in QTc interval,Tp-e interval or Tp-e/QT ratio at T1,2 between the three groups (P＞0.05).Compared with those at T1,the QTc and Tp-e intervals were significantly shortened and the Tp-e/QT ratio was decreased at T2 in P1 and P2 groups,and the Tp-e interval was shorten and the Tp-e/QT ratio was decreased at T2 (P＜ 0.05),and no significant change was found in the QTc interval at T2 in group P3 (P＞0.05).Conclusion Propofol at clinically relevant concentrations can shorten the ventricular repolarization in elderly patients.

Clinical comparison of percutaneous transluminal angioplasty and surgical resection for Cimino-Brescia arteriovenous fistula stenosis in hemodialysis patients / 医学研究生学报

Objeetive As to the high incidence of arteriovenous fistula(AVF) stenosis,surgical operation will result in the exhaustion of vascular resources in patients,while percutaneous transluminal angioplasty(PTA) can maintain vascular resources for ostomy.However,there is still no clear definition between the choices of PTA and surgical resection.The aim of this study was to compare the efficacy of PTA and surgical resection followed by reconstruction for the treatment of arteriovenous fistula stenosis in order to find appropriate treatment.Methods Retrospective analysis had been done on 46 hemodialysis patients with arteriovenous fistula stenosis in Nanjing BenQ hospital from January 2015 to March 2017,which included 22 cases treated with PTA (PTA group) and 24 cases treated with surgical operation (operation group).Comparison was made in general clinical situation,patency rate at six months after surgery,over patency time and adverse reactions to surgery between the two groups.Results The number of stenoses in PTA group was bigger than that in operation group and the difference was of statistic significance (2.78±1.43 vs 1.67±0.71,P＜0.05).There was no significant difference in patency rate between the two groups (P =0.828).There were 57 venous stenoses in PTA group,among which 12 stenoses were anastomotic (21.05％) with 79.3％ average stenosis degree and 43 stenoses were at venous outflow tract of fistula (75.44％) with 84.26 average stenosis degree.In PTA group,3 patients had hematoma brachial puncture position and recovered by self-absorption without special treatment.In operation group,1 patient had mild blood oozing and recovered after treatment;4 patients recovered gradually from mild swelling on the back of the hand of the operation side.No difference was found in adverse reactions between two groups (P＞0.05).Conclusion PTA treatment is preferred for multiple stenoses(n ≥ 3),which ensures better preservation of vascular resources at a comparable patency rate.

Effects of target-controlled infusion of propofol with different concentrations on ventricular repolarization after preoperative infusion of cefuroxime sodium in patients undergoing gynecologic opera-tion / 临床麻醉学杂志

Objective To investigate the effects of target-controlled confusion of propofol with different concentrations on ventricular repolarization after prophylactic infusion of cefuroxime sodium. Methods Sixty ASA physical status Ⅰ or Ⅱ female patients,aged 18-65 years,undergoing elective gynecological surgery were randomly divided into three groups:group P2 (n =20)with TCI 2 μg/ml, group P3 (n =1 9)with TCI 3 μg/ml and group P4 (n =20)with TCI 4 μg/ml.Firstly,they were re-hydrated;secondly,the patients in groups P2,P3 and P4 were intravenous infused with cefuroxime sodium 2.5 g (in 100 ml normal saline)and then target-controlled infused of propofol 2 μg/ml,3μg/ml and 4 μg/ml in target plasma concentration,respectively.At three pionts of time:after rehy-dration before intravenous antibiotics (T0 ),after intravenous antibiotics before TCI of propofol (T1 ), after TCI of propofol (T2 ),QT interval,QTc interval,Tp-e interval were measured and recorded, respectively.Results Compared with T0 ,QTc [(469.9 ± 34.0)ms vs.(451.2 ± 24.9)ms],Tp-e [(107±25)ms vs.(94±20)ms]and Tp-e/QT (0.260±0.058 vs.0.236±0.043)in group P4 were sig-nificantly prolonged at T1 (P < 0.05 ).Compared with T1 ,QTc of groups P2 [(437.4 ± 24.4)ms vs. (453.3±28.0)ms]and P4 [(438.8±29.9)ms vs.(469.9±34.0)ms]were shortened significantly at T2 (P <0.05).Conclusion Propofol could improve ventricular reporlarization heterogeneity caused by cefu-roxime sodium.

Protective effect of topiramate on hypoxic-ischemic brain injury in neonatal rat

OBJECTIVE@#To explore protective effect of topiramate (TPM) on hypoxic-ischemic brain injury.@*METHODS@#A total of 360 neonatal rats were selected then randomly divided into sham operation group, ischemia and hypoxia group, conventional treatment group and degradation therapy group (n=90). After surgical treatment, sham and ischemic hypoxia group were treat with normal saline; conventional treatment group was received TPM solution 100 mg/kg, 2 times/d; degradation therapy group received TPM solution 150 mg/kg, 2 times/d, per 3 d treatment each dosage was reduced 50 mg/kg, the lowest reduced to 50 mg/kg. Four groups received continuous treatment for 10 d. After treatment for 1 d, 4 d, 7 d, 10 d the cerebral edema, neuron-specific enolase (NSE) and γ-aminobutyric acid (GABA) levels and cognitive abilities of four groups were observed.@*RESULTS@#After 1 d, 4 d of treatment, the brain water content and NSE levels in ischemia and hypoxia group, the conventional treatment group and the degradation therapy group were significantly higher than that in sham group (P<0.05), the brain water content and NSE levels of the conventional treatment group and the degradation therapy group were significantly lower than that in the ischemic hypoxia group (P<0.05). GABA levels and learning ability of the ischemia and hypoxia group, the conventional treatment group and degradation therapy group were significantly lower than the sham group (P<0.05), the GABA levels and learning ability of the conventional treatment group and degradation therapy group were significantly higher than the ischemia and hypoxia group (P<0.05). After 7 d, 10 d of treatment, the brain water content and NSE levels in the sham operation group, the conventional treatment group and degradation therapy group were significantly lower than the ischemia and hypoxia group (P<0.05), while the GABA levels and learning ability of these three groups were significantly higher than that in the ischemia and hypoxia group (P<0.05), the GABA levels in the conventional treatment group were significantly higher than degradation therapy group (P<0.05); After 10 d of treatment, the GABA levels of the conventional treatment group were significantly higher than the sham group, the learning ability of the degradation therapy group and sham operation group were significantly higher than the conventional treatment group (P<0.05).@*CONCLUSIONS@#The correct amount of short-term TPM has protective effect on hypoxic-ischemic brain injury, but long-term or excessive use may cause new damage to the brain and reduce the cognitive ability.

Changes in biological behaviors of rat dermal fibroblasts induced by high expression of MMP9 / 世界急诊医学杂志（英文）

BACKGROUND:The high level of matrix metalloproteinase 9 (MMP9) is thought to slow down the healing of diabetic foot ulcers. Whether it can influence the biological behaviors of skin fibroblasts and affect wound healing is stillunclear. The present study aimed to observe changes in the biological behaviors of rat dermal fibroblasts induced by high expression of MMP9 and to clarify the possible mechanisms of wound healing for diabetic foot. METHODS:A cellmodel of skin fibroblast with high expression of MMP9 was established by co-culture of high glucose (22.0 mmol/L) and homocysteine (100 μmol/L). A control group was incubated with normal glucose (5.5 mmol/L). Realtime PCR, ELISA and gelatin zymography were used to detect the MMP9 mRNA, protein expression and activity of MMP9. Flow cytometry, CCK-8, ELISA assay, scratch test and transwellwere used to detect cellproliferation, viability, collagen (hydroxyproline) secretion, horizontal migration and vertical migration of cells. The data were expressed as mean±SD. P value less than 0.05 was considered statistically significant. RESULTS:The expression of MMP9 mRNA, protein levels and the activity of MMP9 were much higher in the high MMP9 group than in the control group (7.05±1.02 vs. 1.00±0.00, 206.9±33.6 pg/mL vs. 40.4±5.9 pg/mL, and 1.47±0.13 vs. 0.57±0.12, respectively,P<0.01). The proportion of S-phase cells, proliferation index, cellviability, collagen (hydroxyproline) secretion, horizontal migration rate and the number of vertical migration cells were lower in the high MMP9 group than in the control group (P<0.01). CONCLUSION:Fibroblasts with a high expression of MMP9 decreased proliferation, activity, secretion and migration of collagens, suggesting that MMP9 may inhibit the biological behaviors of fibroblasts.

Association of higher resistin levels with inflammatory activation and endothelial dysfunction in patients with essential hypertension / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Some studies have shown that serum resistin levels increase in hypertensive patients. Whether the increase of resistin is related to inflammatory or vascular endothelial function is still unknown. We investigated the relationship of increased resistin levels to inflammatory factors and circulating biomarkers of vascular endothelial function in hypertensive patients.</p><p><b>METHODS</b>One hundred and forty-four nondiabetic patients with new onset, hypertension were recruited. Blood pressure, blood glucose, insulin, resistin, tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), von Willebrand factor (vWF), endothelin-1 (ET-1) and nitric oxide (NO) were measured. The homeostasis model assessment, insulin resistance index (HOMA-IR) was calculated. Patients were divided into two groups according to the median level of resistin. Cytokine levels and indicators of vascular endothelial function were compared. Multiple linear regression was used to determine factors influencing resistin.</p><p><b>RESULTS</b>Serum resistin ranged from 2.57 ng/ml to 20.18 ng/ml in hypertensive patients. High resistin group (> 8.36 ng/ml) had higher levels of TNF-α, IL-6, vWF and ET-1 but lower level of NO compared with low resistin group (P < 0.01). Resistin was positively correlated with body mass index, systolic blood pressure, HOMA-IR, low-density lipoprotein cholesterol, TNF-α and ET-1 but negatively correlated with NO (all P < 0.05). Multiple linear regression analysis revealed that HOMA-IR, TNF-α, NO and ET-1 are independent predictors of resistin with standardized regression coefficients of 0.625, 0.368, -0.260 and 0.222, respectively (all P < 0.01).</p><p><b>CONCLUSIONS</b>We conclude that higher resistin levels are associated with inflammatory activation and endothelial dysfunction, because patients with essential hypertension have increased TNF-α, IL-6, vWF and ET-1 and decreased NO. Moreover, the statistical association of resistin with TNF-α, NO and ET-1 suggests involvement of resistin in the progression of hypertension by influencing inflammation and endothelial function.</p>

Effects of high matrix metalloproteinase 9 on the biological behaviors of rat dermal fibroblasts / 中华急诊医学杂志

Objective To study the effects of high matrix metalloproteinase 9 (MMP 9 ) on the biological behaviors of fibroblasts,in order to clarify the possible mechanisms in the wound healing of diabetic foot.Methods Establish the cell model of skin fibroblast with high expression of MMP 9 by high glucose (22.0 mmol/L) and high homocysteine (100 μmol/L) co-culture.Control group was incubated with normal glucose (5.5 mmol/L).Realtime PCR,ELISA and gelatin zymography were used to detect the MMP 9 mRNA,protein expression and activity of MMP 9.Flow cytometry,CCK-8,ELISA assay,scratch test and transwell were used to detect cell proliferation,viability,collagen (hydroxyproline) secretion,horizontal migration and vertical migration of cells.Results Data were expressed as (x- ± s).Differences were considered significant if their P value was ＜ 0.05.Results The expression of MMP 9 mRNA,protein levels and the activity of MMP 9 in high MMP 9 group were 6.05 folds,4.12 folds and 1.58 folds higher than those in control group (P ＜ 0.01,respectively).The proportion of S phase cells,proliferation index,cell viability,collagen (hydroxyproline) secretion,6 h horizontal migration rate and the number of vertical migration cells in high MMP9 group decreased by 29.8 ％,18.1％,23.3 ％,68.7 ％,45.0 ％ and 21.4 ％ than those in control group (P ＜ 0.01,respectively ). Conclusions Fibroblast with high expression of MMP 9 have decreased proliferation,activity,collagen secretion and reduced migration,which suggests that MMP 9 may inhibit the biological behaviors of fibroblasts.

Construction of recombinant adenovirus containing human HCN4 gene and its transfection efficiency in rat bone marrow mesenchymal stem cells / 中国组织工程研究

BACKGROUND:The hyperpoladzation-activated cyclic nucleotide-gated cation channel (HCN) gene is not increase the risk of induced cardiac arrhythmia,and can accept the modulation function of autonomic nervous system.Therefore,it is the first candidate gene for biological pacemakers.OBJECTIVE:To construct recombinant adenovirus vector containing human HCN4 gene and evaluate its transfection efficency in rat bone marrow mesenchymal stem cells (MSCs).DESIGN,TIME AND SETTING:The in vitro cytology-gene experiment was performed at the Lin Bai-xin Experimental Center,Second Hospital of Sun Yat-sen University from February to September 2008.MATERIALS:Ten SD rats were supplied by the experimental animal center of Sun Yat-sen University.Rlasmid pcDNA3.1-HCN4 containing target gene human HCN4,human embryo kidney 293 cells and Escherichia coll DH5α were preserved by our experimental center;Shuttle plasmid pShuttle-CMV containing green fluorescent protein gene and adenoviral backbone plasmid pAdxsi were bought from SinoGenoMax Co.,Ltd.METHODS:HCN4 cDNA segment was liberated from the cloning vector of pcDNA3.1-HCN4 via Hind Ⅲ+Xba Ⅰ,and subcloned into pShuttle-CMV,which was digested by I-Ceu Ⅰ +I-Sce Ⅰ double enzyme and subcloned into adenoviral plasmid to form recombinant adenovirus plasmid.Recombinant adenovirus plasmid was transfected into 293 cell lines by liposome,and the recombinant adenovirus AdHCN4 was packaged and transfected into rat MSCs.MAIN OUTCOME MEASURES:The identification of recombinant adenovirus plasmid vector,identification of recombinant adenovirus and its titration test;the transfection efficiency of recombinant adenovirus.RESULTS:Cloned sequence about 3.6kbp was obtained by Hind Ⅲ+Xho Ⅰ digestion after HCN4 cDNA segment was cloned into pShuttle-CMV.DNA sequencing results indicated that the clone location was correct.Recombinant adenovirus plasmid was cut into seven fragments while empty vector gained only six fragments after digested by Xho Ⅰ.The recombinant adenovirus was pathogenic to 293 cells after recombinant adenovirus plasmid was packaged in it.HCN4 cDNA (657bp) was amplified by PCR with virus titer of 2.5×10~(11) PFU/mL after transfected 293 cells with supematant.The efficiency of recombinant adenovirus infecting rat MSCs was about 90% when multiplicity of infection was 800.Rat MSCs expressed green fluorescence after transfection.CONCLUSION:The adenovirus vector with human HCN4 cDNA was established successfully,which can effectively transfect rat MSCs.

Blockades of angiotensin and aldosterone reduce osteopontin expression and interstitial fibrosis infiltration in rats with myocardial infarction / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It has been reported that osteopontin has an important role in cardiac fibrosis and remodeling. However, its direct mechanisms remain unclear. The purpose of this study was to investigate the role of angiotensin and aldosterone blockades in cardiac osteopontin expression associated with cardiac remodeling in myocardial infarcted (MI) rats.</p><p><b>METHODS</b>Fifty SD rats that survived 24 hours after ligating left anterior descending coronary artery were randomly divided into three groups: MI-saline group (n = 15, 5 ml/d), MI-perindopril group (n = 18, perindopril 2 mgxkg(-1)d(-1)) and MI-spironolacton (n = 17, spironolacton 20 mgxkg(-1)xd(-1)). A sham operation group (n = 15) was selected as non-infarcted control. At 6 weeks after treatment, hemodynamic pararmeters and left ventricular function were measured with catheterization, interstitial fibrosis infiltration and cardiomyocyte diameters were evaluated histologically. Myocardium osteopontin protein expression level in the non-infarcted myocardium was detected by Western blotting.</p><p><b>RESULTS</b>No osteopontin protein was detected in the myocardium of sham-operation rats. High levels of osteopontin protein expression were detected in the MI-saline rats, but the levels were suppressed in the MI-perindopril and MI-spironolacton rats at 6 weeks following MI (P < 0.01, respectively). Compared with the sham operation group, all rats in the MI group showed marked interstitial fibrosis infiltration in the non-infarction area, higher ventricular weight/body weight ratio, significantly increased cardiomyocyte diameter (P < 0.01, respectively), and developed significant systolic and diastolic dysfunction as indicated by decreased left ventricular systolic pressure (LVSP) and +/-dp/dt, as well as increased left ventricular end-diastolic pressure (LVEDP) (P < 0.01, respectively). Angiotensin and aldosterone blockades partly prevented cardiac fibrosis and systolic and diastolic dysfunction (P < 0.01, respectively).</p><p><b>CONCLUSION</b>Treatment with angiotensin and aldosterone blockades inhibits expression of osteopontin in the non-infarcted myocardium and prevents cardiac remodeling following MI.</p>

Effects of oxidative stress on ventricular remodeling after myocardial infarction in rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effects of oxidative stress on ventricular remodeling after acute myocardial infarction (AMI) in rats.</p><p><b>METHODS</b>AMI was induced in 20 SD rats by ligation of the anterior descending coronary artery, and another 12 rats without the ligation served as the sham-operated group. Six weeks after the operation, the heart mass index (HMI), left ventricular mass index (LVMI), right ventricular mass index (RVMI), the indexes of heart function, cardiac myocyte apoptosis index, collagen content and collagen I/III ratio and the indexes of oxidative stress were measured.</p><p><b>RESULTS</b>After AMI, HMI, LVMI and RVMI increased significantly (P<0.05), the heart function deteriorated significantly (P<0.01), and the cardiac myocyte apoptosis index in the non-infarct area, collagen content and collagen I/III ratio in the infarct and non-infarct areas were all significantly increased (P<0.05 or 0.01). Myocardial superoxide dismutase (SOD) activity was significantly lowered after AMI, which resulted in significantly increased myocardial malondialdehyde (MDA) level and decreased ratio of SOD/MDA (P<0.05). Correlations were found between the indexes of oxidative stress in myocardium, those of the heart function and those pertaining to ventricular remodeling after AMI.</p><p><b>CONCLUSION</b>Oxidative stress may be involved in ventricular remodeling after AMI, and antioxidants can be an option for treatment of ventricular remodeling.</p>

Association of angiotensin I-converting enzyme gene polymorphism with ACE and PAI-1 levels in Guangdong Chinese Han patients with essential hypertension / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the association between angiotensin I-converting enzyme (ACE) gene and the levels of ACE and PAI-1 in Chinese Han patients with essential hypertension (EH) in Guangdong Province.</p><p><b>METHODS</b>Polymerase chain reaction was used to examine the ACE genotype, colorimetry used to measure the serum ACE level, and spectrophotometric assay performed to examine the plasma PAI-1 level in 115 EH patients and 96 healthy controls in Guangdong Province.</p><p><b>RESULTS</b>The ACE DD genotype and D allele frequencies were significantly higher in EH group than in the control group (P<0.05), and the EH patients also had significantly higher serum ACE level and plasma PAI-1 level than the control subjects (P<0.01). The serum ACE level was positively correlated with plasma PAI-1 level in both EH group and control group (r=0.7913 and 0.7806, respectively, P<0.01). In EH group, the patients with DD genotype showed significantly higher serum ACE and plasma PAI-1 levels than those with ID and II genotypes (P<0.01), and patients with ID genotype had significantly higher ACE and PAI-1 levels than those with II genotype (P<0.05).</p><p><b>CONCLUSION</b>The DD genotype and D allele of ACE gene can be risk factors for essential hypertension in Chinese Han subjects in Guangdong Province, and the EH patients have elevated serum ACE and plasma PAI-1 levels. Increased ACE level due to DD polymorphism may play an important role in elevating plasma PAI-1 level. The genetic variation of ACE contributes to the balance of fibrinolytic pathway, which may be one of the pathological mechanisms linking the ACE I/D genotype and EH.</p>

Characteristics of ventricular electrophysiology in a right ventricular rapid pacing-induced canine heart failure model / 中国病理生理杂志

AIM:To research the characteristics of ventricular electrophysiology in right ventricular rapid pacing-induced congestive heart failure (CHF) dogs. METHODS:Dogs (n = 16) were randomly divided into 2 groups:the control (n = 7) and the CHF group (n = 9) induced by rapid right ventricular pacing at 240 pulse·min-1 for 4 to 5 weeks. The electrophysiologic parameters were evaluated by the technique of standard electric stimulation and monophasic action potential (MAP) recording. RESULTS:(1) Ventricular effective refractory period (VERP), ventricular MAP duration (MAPD90), ventricular late repolarization duration (VLRD) and intra- ventricular conduction time (IVCT) were prolonged by 26％ (P ＜ 0. 01), 43％ (P ＜ 0. 01), 318％ (P ＜ 0. 05), and 19％ (P ＜ 0. 01), respectively in CHF group. (2)The ratio of VERP to MAPD90(VERP/MAPD90) was decreased by 13％ (P＜0.05) in CHF group. (3) The dispersion of ventricular recovery time (VRT - D) was increased by 185％ (P ＜0. 01) in CHF group. (4) The ventricular fibrillation threshold (VFT) was decreased by 48％ (P ＜ 0. 01) in CHF group. CONCLUSION:The abnormal electrophysiological changes in the CHF condition may be contributing factors of lethal ventricular arrhythmias and sudden cardiac deaths in CHF.

Effects of Probucol on Expression of Bcl-2,Bax and Oxidative Stress in Myocardial Infarcted Rats / 中华高血压杂志

Background Cardiomyocytes apoptosis was related to oxidative stress which has been shown to play an important role in ventricular remodeling after myocardial infarction(MI).Probucol is a hypolipidemic and antioxidant agents.Several reports demonstrated its cardioprotective effect after MI.However,the exact effect of probucol on the modification of the apoptosis related gene Bcl-2 and Bax is not clear.Objective To investigate the effects of probucol on mRNA and protein expression of Bcl-2,Bax and oxidative stress in myocardial infarcted rats.Methods Forty-one SD rats that survived 24 h after ligating left anterior descending coronary artery were randomly to receive placebo-saline(5 mL/d,n=20)or probucol(probucol 60 mg/kg?d,n=21).Twelve rats underwent sham operation were served as control(n=12).Six weeks after treatment,hemodynamic pararmeters and left ventricular function were measured with catheterization.Cardiomyocytes apoptosis were determined by TUNEL method.Myocardium mRNA of Bcl-2 and Bax expression levels in the non-infarcted myocardium were as- sessed by RT-PCR.The myocardium protein expression of Bcl-2 and Bax in the non-infarcted myocardium were de- termined by Western blot.Colorimetry was used to determine oxidative metabolism index in myocardium.Results 1)Compared with the sham rats,all MI rats showed marked decrease in Bcl-2 mRNA and protein expression in myo- cardium with increase of Bax mRNA and protein expression and apoptosis index(P

The reconstruction of bioengineer active corneal stroma and its biocompatibility study / 生物医学工程学杂志

This paper aims to explore the biocompatibility of bioengineer active corneal stroma (BACS), as the biological carrier for cornea reconstruction, to provide the basis for future study on clinic application. The cells and immunogenic components of cornea stroma were removed through different extract methods. A complex of functional corneal stroma cells and acellular corneal stroma was used to reconstruct BACS. Their morphological characteristics and ultrastructures were observed with transmission electron microscope. The complex was grafted into interlamellar stromal pockets. Cells were labeled by BrdU to examine the survival and conversion after grafting. The cells could survive and proliferate in acellular corneal stroma. All the nuclei of the corneal stromal cells showed positive labeling with BrdU in the BACS. After 4 weeks, BACS became transparent; after 8 weeks, the bioengineer active cornea stroma was fully reconstructed.

Treatment of rabbit corneal with skin epidermal stem cells / 中国医学科学院学报

<p><b>OBJECTIVE</b>To construct artificial rabbit corneas with autologous skin epidermal stem cells and allogenic stromal cells in vitro and promote healing of corneal wounds.</p><p><b>METHODS</b>Skin epidermal stem cells were isolated from autologous skin samples. Keratocytes were isolated from newborn cornea biopsies. The cells were combined with acellular porcine corneal stroma scaffold to construct artificial corneas. Then the constructed artificial corneas were used to repair severe vision loss caused by complete loss of corneal epithelial stem cells.</p><p><b>RESULTS</b>Cultured skin epidermal stem cells and keratocytes were in good growth conditions. Cultured artificial corneas consisted of multiplayer epithelial cells growing on stroma equivalent consisting of stromal matrix with incorporated keratocytes. The in vitro constructed artificial corneas were histologically similar to normal rabbit corneas. Three months after transplantation, the cornea wounds were healed and the rabbit cornea became transparent.</p><p><b>CONCLUSION</b>The artificial corneas were constructed successfully in vitro and can be used to repair severe vision loss caused by complete loss of corneal epithelial stem cells.</p>