Primary percutaneous coronary intervention in a COVID-19 patient with ST-segment elevation myocardial infarction after lung transplantation: a case report / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

We present an unusual case of a patient with bilateral-lung transplantation due to severe coronavirus disease 2019 (COVID-19), who subsequently suffered complications with acute myocardial infarction and underwent primary percutaneous coronary intervention (PCI).

Study on the efficiency of the European System for Cardiac Operative Risk Evaluation (EuroSCORE)in predicting in-hospital mortality of the patients with percutaneous coronary intervention / 中华流行病学杂志

Objective To investigate the efficiency of European System for Cardiac Operative Risk Evaluation(EuroSCORE)in predicting in-hospital mortality for the patients after percutaneous coronary intervention(PCI). Methods Retrospective analysis was conducted on the patients who had undergone PCI in our hospital since year 2005 to 2007. We used both cumulative EuroSCORE score and logistic EuroSCORE to predict the in-hospital morality and to analyze the correlation between the predicted mortality and the actual mortality. Results According to the additive EuroSCORE, we divided the patients into three groups, the additive EuroSCORE 0-2 were divided into low-risk group,3-5 were divided into mid-risk group and ≥6 into high-risk group.The actual in-hospital mortality rates were 0%, 0.47% and 6.09% respectively. The EuroSCORE model demonstrated an overall relation between the EuroSCORE ranking and the incidence of in-hospital mortality(P<0.001). Results from the multivariable logistic regression analysis showed that the EuroSCORE was an independent in-hospital mortality predictor(P<0.01). Conclusion The EuroSCORE risk model and the in-hospital mortality were significantly correlated, indicating that the model was a promising method for predicting the in-hospital mortality of PCI patients.

Interleukin-1beta upregulates matrix metalloproteinase-2 expression and activity in cardiac fibroblasts via nitric oxide synthase pathway / 中华心血管病杂志

<p><b>OBJECTIVE</b>To investigate the effect of interleukin-1beta (IL-1beta) on expression and activity of matrix metalloproteinase-2 (MMP-2) of cultured human cardiac fibroblasts and related signaling pathway.</p><p><b>METHODS</b>Primary human cardiac fibroblasts seeded in 6-well tissue culture plates and cultured to 80% to 90% confluence were harvested at passage 3 to 6 and exposed to IL-1beta at various concentrations for 24 h, culture supernatant and cell protein were obtained. MMP-2 mRNA was determined by RT-PCR. The activity of MMP-2 was analyzed by zymography and the expression of inducible nitric oxide synthase (iNOS) protein level was detected by Western blot analysis. Assessment of NO production in the culture supernatant was performed using the Griess method.</p><p><b>RESULTS</b>IL-1beta (4 ng/ml) significantly increased MMP-2 activity of cultured fibroblasts in a time-dependent manner. MMP-2 mRNA expression was significantly upregulated by IL-1beta (4 ng/ml and 10 ng/ml, all P<0.01). Moreover, IL-1beta also significantly increased NO production in supernatant (P<0.01) and these effects could be significantly blocked by cotreatment with L-NMMA (10(-3) mol/L, all P<0.01). Western blot analysis showed that iNOS could not be detected in unstimulated human cardiac fibroblasts but could be detected in cardiac fibroblasts exposed to IL-1beta.</p><p><b>CONCLUSION</b>IL-1beta increased MMP-2 activity and transcription of human cardiac fibroblasts via iNOS-NO pathway.</p>

Cloning, expression and sequence analysis and tissue distribution of angiotensin-converting enzyme 2 (ACE2) gene in adult mice / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>o clone angiotensin-converting enzyme 2(ACE2) gene, to analyze its amino acids and nucleotides sequence and to investigate tissue distribution of ACE2 in adult mice.</p><p><b>METHODS</b>The full-length ACE2 encoding sequence was amplified from the RNA of mice kidney tissue by RT-PCR technique, cloned into plasmid pGEM-T easy, then subcloned into plasmid pcDNA3.1+. After identification of DNA sequence, the recombinant plasmid pmACE2 was transfected into Cos7 cells with lipofectin reagent. The transient expression of ACE2 molecule was detected by SDS-PAGE. Sequence analysis was conducted with CLUSTALX program. Tissue distribution of ACE2 in mice was detected by RT-PCR.</p><p><b>RESULTS</b>A fragment about 2.6 kb was amplified and the recombinant plasmid pmACE2 was confirmed by two-enzyme digesting and DNA sequencing. The cloned DNA sequence was consistent with that previously reported, except for 3 variations: A701G, T1102C and T1330C. SDS-PAGE proved that expression of a soluble, truncated products form of ACE2 was a glycoprotein of approximately 80 kD in Cos7 cells. The predicted mice ACE2 sequence contained an N-terminal signal sequence (amino acid residues 1-18), a single HHEMGHIQ zinc-binding domain (amino acid residues 373-380) and C-terminal membrane anchor (amino acid residues 738-765). Mice ACE2 showed 84 % identity with that of human, and 90 % identity with that of rat. Expression of ACE2 was the greatest in lungs, hearts and kidneys, and moderate levels were also detected in testes and livers.</p><p><b>CONCLUSION</b>Mice ACE2 gene has been cloned and successfully expressed in vitro. The tissue-specific expression of ACE2 in different species is not identical.</p>

Identification of a novel mutation at the point of low density lipoprotein receptor gene from a subject with familial hypercholesterolemia / 生理学报

Family hypercholesterolemia (FH) is a genetic disorder caused by mutation in the low density lipoprotein receptor (LDLR) gene. It is characterized by a high concentration of low density lipoprotein (LDL), which frequently gives rise to tendon xanthenes and premature coronary artery disease. We studied a FH family ,which was diagnosed by clinical features and blood lipid tests. The Total cholesterol level of the family was 19.05 mmol/L and the LDL level was 17.06 mmol/L in the proband homozygous FH subjects, while the total cholesterol was 7.96 mmol/L and LDL was 5.55 mmol/L in the heterozygous FH subjects. DNA segments amplified with PCR were sequenced in heterozygous and homozygous FH patients. Two novel identical mutation alleles of GAG683GCG, which caused an amino acid change from Glu to Ala, were detected in Exon4 of LDL receptor gene in homozygous proband. DNA sequencing revealed that the proband's parents were heterozygotes with the same mutational alleles as the proband. These results are in coincidence with the clinical diagnoses. Moreover Epstein-Barr virus transformed lymphocytes (EBV-Ls) were derived by routine virus infection transforming protocol. The cells bounded with the fluorescently conjugated LDL were measured by fluorescence flow cytometry. The ratios of functional LDLR in EBV-Ls originated from homozygous FH, heterozygous FH and normal control were 7.02%, 62.64% and 84.69%, respectively. As a result, the homozygous FH patient's LDLR had 8.29% and the heterozygous FH patient's LDLR had 73.96% of the activity of the control. It is apparent that LDL receptor activity of homozygous FH subject is significantly lower than normal control. The data from fluorescence flow cytometry analysis of EBV-Ls strongly support the clinical diagnoses and the results of DNA sequencing. In accordance with the updated version of UMD-LDLR, the mutant GAG683GCG in Exon4 of LDLR gene which we have identified is a novel mutation of the LDLR gene in human with hypercholesterolemia.

Single nucleotide polymorphism in SCN5A and the distribution in Chinese Han ethnic group / 生理学报

Mutations in voltage-gated sodium channel type (SCN5A) may evoke severe, life-threatening disturbances in cardiac rhythm, including long QT syndrome, idiopathic ventricular fibrillation (Brugada Syndrome), and isolated cardiac conduction disease. There is increasing awareness of the role of common polymorphisms in altering gene function and in susceptibility to diseases. The aim of the present study was to investigate single nucleotide polymorphism (SNP) in SCN5A gene and the distribution of these identified SNPs in Chinese Han nationality. SCN5A gene was sequenced by fluorescent labeling automatic sequencing method in 120 unrelated samples from Han nationality in South China. Allele frequency distribution was tested by Hardy-Weinberg equilibrium. The results showed that a total of 5 SNPs were identified in SCN5A gene, including three SNPs in code region, one SNP in regulatory region and the other in intron 23 adjacent to donor splicing site. The distribution of the SNPs in SCN5A gene was uneven. These allele frequencies in Han population of South China were as follows: G87A (A29A) 27.5%, A1673G (H588R) 10.4%, 4245+82A>G 32.8%, C5457T (D1819D) 41.3% and G6174A 44.9% respectively. The SNPs G87A (A29A), 4245+82A>G and G6174A were reported for the first time. There was no significant difference in the allele frequency of A1673G (H558R) within different ethical populations (P>0.05). C5457T (D1819D) allele frequency of Han population in South China was similar to that observed in Japanese (P>0.5), but higher than that in American (p<0.005). There was no significant difference in the distribution of the SNPs between male group and female group (all p>0.05). S1102Y and other 10 SNPs identified in other ethnic populations have not been detected in Chinese Han population. The allele distribution of SNPs was in good unity with the Hardy-Weinberg equilibrium. It is suggested that the SNP distribution of SCN5A gene varies within different nationalities. These data will be of use for genetic association studies of acquired arrythmias and investigation of sensitivity to drug therapy.

Effects of puerarin on number and activity of endothelial progenitor cells from peripheral blood / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate whether puerarin can augment endothelial progenitor cells (EPCs) numbers, promote EPC proliferation, migration and adhesion.</p><p><b>METHOD</b>Total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days culture, attached cells were stimulated with puerarin (to make a series of final concentrations: 0. 1, 0.5, 1, 3 mmol x L(-1)) or vehicle control for the respective time points (6, 12, 24, 48 h). EPCs were characterized as adherent cells double positive for DiLDL-uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. EPCs proliferation, migration and in vitro vasculogenesis activity were assayed with MT assay, modified Boyden chamber assay and in vitro vasculogenesis kit, respectively. EPCs adhesion assay was performed by replating those on fibronectin-coated dishes, then adherent cells were counted.</p><p><b>RESULT</b>Incubation of isolated human MNCs with puerarin dose increased the number of EPCs, maximum at 3 mmol x L(-1), 24 hours (approximately 1-fold increase, P < 0.01). In addition, puerarin also promoted EPC proliferative, migratory, adhesive and in vitro vasculogenesis capacity.</p><p><b>CONCLUSION</b>Puerarin can augment the number of EPCs with enhanced functional activity.</p>

Single nucleotide polymorphisms of the SCN5A gene in Han Chinese and their relation with Brugada syndrome / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Mutations in the cardiac sodium channel gene (SCN5A) may lead to a broad spectrum of familial arrhythmias, including long QT syndrome (LQTS), idiopathic ventricular fibrillation (IVF), and isolated cardiac conduction diseases. Recent studies have shown that polymorphisms in the SCN5A gene also play an important role in the manifestation of disorders involving cardiac excitability. In this study, we investigated the polymorphisms of the SCN5A gene in Han Chinese and its relation to Brugada syndrome (BS).</p><p><b>METHODS</b>Genomic DNA was isolated from 120 unrelated healthy volunteers and 48 unrelated Brugada syndrome patients by means of standard procedures. All exons including the putative splicing sites of the SCN5A gene were amplified by PCR and sequenced directly or after subcloning using an ABI Prism 377 DNA sequencer.</p><p><b>RESULTS</b>A total of 5 single nucleotide polymorphisms (SNPs) were identified in the Han Chinese population, including 3 novel ones: G87A(A29A), 4245 + 82A > G, and G6174A. The allele frequencies of each SNP in the Han Chinese population were as follows: G87A (A29A) 27.5%, A1673G (H558R) 10.4%, 4245 + 82A > G 32.8%, C5457T (D1819D) 41.3%, and G6174A 44.9%. S1102Y and 10 other SNPs identified in other ethnic populations were not detected in this study. There was no significant difference in the allele frequency of A1673G (H558R) between different ethnic populations (all P > 0.5). On the other hand, the allele frequency of C5457T (D1819D) among Han Chinese was similar to its frequency among Japanese (P > 0.5), but higher than that among Americans (P < 0.005). The allele G1673 (R558) was over-represented in BS patients compared to controls (P < 0.005), but there was no significant difference in genotype frequencies at this locus. There were also no differences in either the allele or genotype frequencies of the 4 other identified SNPs when comparing BS patients with healthy controls.</p><p><b>CONCLUSIONS</b>The distribution of SCN5A SNPs may vary between different ethnicities. The polymorphism of A1673G might be associated with BS and may contribute to a susceptibility to BS in Han Chinese.</p>

Effects of Ginkgo biloba extract on number and activity of endothelial progenitor cells from peripheral blood / 药学学报

<p><b>AIM</b>To investigate whether Ginkgo biloba extract can augment endothelial progenitor cell (EPC) number, and promote EPC proliferation, migration and adhesion.</p><p><b>METHODS</b>Total mononuclear cells (MNCs) were isolated from peripheral blood by Ficoll density gradient centrifugation, and then the cells were plated on fibronectin-coated culture dishes. After 7 days of culture, attached cells were stimulated with Ginkgo biloba extract (10, 25 and 50 mg x L(-1)) or vehicle control for the respective time points (6, 12, 24 and 48 h). EPC were characterized as adherent cells double positive for DiLDL-uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope. EPC were further documented by demonstrating the expression of CD34, VEGFR-2 and AC133 with flow cytometry. EPC proliferation, migration and in vitro vasculogenesis activity were assayed with MTT assay, modified Boyden chamber assay and in vitro vasculogenesis kit, respectively. EPCs adhesion assay was performed by replating MNCs on fibronectin-coated dishes, and then counting adherent cells.</p><p><b>RESULTS</b>Incubation of isolated human MNCs with Ginkgo biloba extract increased the number of EPC, maximum at 25 mg x L(-1), 24 hours (approximately 1-fold increase, P < 0.01). In addition, Ginkgo biloba extract promotes EPC proliferative, migratory, adhesive and in vitro vasculogenesis capacity.</p><p><b>CONCLUSION</b>Ginkgo biloba may promote EPC augmentation and enhance its functional activity.</p>

Effect of puerarin on L-type calcium channel in isolated rat ventricular myocytes / 中国中药杂志

<p><b>OBJECTIVE</b>To observe the effect of Puerarin on L-type calcium channel in isolated rat ventricular myocytes.</p><p><b>METHOD</b>The cardiac ventricular myocytes were isolated enzymatically by Langendorff perfusion techniques at constant flow rate. Whole-cell recording of patch-clamp techniques was used to observe the current of L-type calcium channel.</p><p><b>RESULT</b>Puerarin 2.4 mmol x L(-1) could inhibit the current of L-type calcium channel of rat ventricular myocytes and this inhibition was time-dependent. Purerarin elevated the current-voltage (I-V) curve of calcium current.</p><p><b>CONCLUSION</b>Puerarin can inhibit L-type calcium current of rat ventricular myocytes. Which implies that puerarin takes part in anti-myocardial ischemia and anti-arrhythmics partly due to the inhibition of L-type calcium channel.</p>

Dependence of ventricular wallstress-induced refractoriness changes on pacing cycle lengths and its mechanism / 生理学报

The aim of this article was to investigate the dependence of ventricular wallstress-induced refractoriness changes on pacing cycle lengths and its mechanism in anaesthetized rabbits. The rabbit heart preparation was used. The left ventricular afterload was increased by partially clipping the root of the ascending aorta. The changes in effective refractory periods (ERP) induced by the left ventricular afterload rising were examined at different pacing cycle lengths (1000, 500, 300 and 200 ms). In addition, the effect of streptomycin on these changes was also observed. The results are as follows: (1) The rising of left ventricular afterload led to marked changes in ERP at rapidly pacing cycle lengths (300 ms, 21+/-5 ms, 17.0%; 200 ms, 19+/-3 ms, 18.8%. P<0.01) than at slow ones (1000 ms, 3+/-2 ms, 1.5%; 500 ms, 7+/-3 ms, 4.0%. P>0.05); (2) Streptomycin inhibited the changes caused by the left ventricular afterload rising at pacing cycle lengths 300 ms and 200 ms (P>0.05). It is suggested that ventricular wallstress-induced refractoriness changes are pacing cycle length-dependent, and the effect of streptomycin appears to be consistent with the inhibition of stretch-activated ion channels.