OBJECTIVETo explore the alterations of after depolarization and triggered activity in myocardiac muscle during progression of mouse aortic stenosis.

METHODSAfter the establishment of mouse aortic stenosis model, the heart was collected and intracellular potential was recorded using standard glass microelectrode. After the recording, the action potential (AP), early after depolarization (EAD), delayed after depolarization (DAD) in papillary muscles were analysed.

RESULTS(1) Compared with that of time-matched control mice, there were no changes of the action potoutial duration at 90% repolarization(APD90) in model mice at 2 and 5 weeks, whereas the APD90 was progressively prolonged at 9 and 13 weeks. (2) During the 30 minites of the experiment, spontaneous EADs and DADs were frequently present in medel mice at 9 and 13 weeks, were not in control and model mice at 2 and 5 weeks. (3) Compared with those of control group, EADs and DADs triggered by hypokalaemia or isoproterenol were increased significantly. The incidence rate of triggering EADs and DADs was progressively increased over time.

CONCLUSIONEAD, DAD and trigger activities increase gradually during the process of aortic stenosis, and it suggests that the myocardium electrical-instability is markedly increased in the insult hearts.

Action Potentials ; physiology ; Animals ; Aortic Valve Stenosis ; physiopathology ; Disease Models, Animal ; Male ; Mice ; Myocytes, Cardiac ; physiology

OBJECTIVETo find the characteristic parameters from electrocardiogram (ECG) which is most related to pathological progress, surface ECG was performed in mice at 2, 5, 9 and 13 week post surgery.

METHODSElectrocardiogram recordings: The mice were anaesthetized with tribromoethanol (250 mg/kg, i.p.). Lead II surface ECG were acquired by using the Biopac System MP150 at a rate of 5 kHz.

RESULTS(1) No arrhythmia was observed in Sham and 2-week Band mice. Spontaneous arrhythmias were observed in ECG recordings, with an incidence of 15%, 28% and 63% in 5-, 9- and 13-week Band mice, respectively. Tachyarrhythmias, such as frequent premature ventricular extrasystole, bigeminy, trigeminy, and paroxysmal tachycardia were found. (2) Analysis of ECG recordings revealed a significant prolongation of QT and QTc intervals. Compared with age-matched Sham mice, the increment in QT and QTc intervals was 20.4%, 32.7%, 49.7%, 61.0% and 27.1%, 32.1%, 43.9%, 59.1% at 2, 5, 9 and 13 week, respectively (P < 0.01). (3) The characteristic change in electrocardiogram was on the J wave. The amplitude of J wave was upward in Sham mice, and it was significantly flattened or inverted in Band mice. (4) Except that RR interval at 2 week showed a slight decrease, there was no significant change in PR interval and RR interval in Band mice.

CONCLUSIONIn the present study, we found that the increase incidence of spontaneous arrhythmias, prologation of QT interval and changes in the amplitude of the J wave in the surface ECG during progression of mouse cardiac hypertrophy and failure, and the progressive pattern indicated that a gradual aggravation of the ventricular repolarization delay in this mouse model.

Animals ; Cardiomegaly ; physiopathology ; Disease Models, Animal ; Electrocardiography ; Male ; Mice

Objective To establish a tree shrew mode of breast tumor.Method Forty-five 3 to 4 month-old female tree shrews were orally gavaged with 20 mg 7,12-dimethylbenz(a)anthracene (DMBA) or peanut oil per animal for three times.Following that, fifteen DMBA administrated tree shrews were implanted 90 day-release medroxyprogesterone acetate ( MPA) pellets.The tree shrews were palpated once weekly to detect mammary tumors for 45 weeks after first DMBA administration.Results DMBA were able to induce breast tumors (12.5%) in tree shrews, and MPA increased the tumor incidence (50%) while no breast tumors were observed in the control group.Three induced breast tumors were intraductal papillary carcinomas and one was IDC by H&E stain.Conclusion All induced tumors are similar with spontaneous tumors in structure and molecular markers.

Objective: To observe the clinical efficacy of heat-sensitive moxibustion for adjuvant treatment of depression in Parkinson disease and explore its mechanism. Methods: A total of 80 patients with Parkinson disease coupled with depression were randomized into an observation group and a control group, with 40 cases in each group. The control group was treated with levodopa and benserazide hydrochloride tablets and paroxetine tablets, while the observation group was treated with heat-sensitive moxibustion on the basis of the medications in the control group. The treatment course was 2 months. The Hamilton depression scale-17 (HAMD-17), unified Parkinson's disease rating scale (UPDRS) and Parkinson's disease quality of life questionnaire-39 (PDQ-39) were scored before and after the treatment, and the efficacy was evaluated after treatment. Levels of patients' serum dopamine (DA), 5-hydroxytryptamine (5-HT), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were detected before and after the treatment. Results: After treatment, the total effective rate of the observation group was higher than that of the control group (P<0.05). The HAMD-17 scores in the two groups decreased significantly after treatment (both P<0.05), and the score in the observation group was obviously lower than that in the control group (P<0.05). The component scores and total scores of UPDRS in both groups decreased significantly (all P<0.05), and the scores in the observation group were lower than those in the control group (all P<0.05). The score of PDQ-39 in the observation group decreased significantly (P<0.05), and was lower than that in the control group (P<0.05). After treatment, the serum DA and 5-HT levels in the observation group increased significantly (both P<0.05) and the TNF-α and IL-6 levels decreased significantly (both P<0.05), which were statistically different from those in the control group (all P<0.05). Conclusion: Heat-sensitive moxibustion has certain auxiliary effect in treating depression in Parkinson disease, significantly improving clinical symptoms and the quality of life, which may be related to the up-regulation of DA and 5-HT levels and down-regulation of TNF-α and IL-6 levels.

Ginsenosides are the abundant secondary metabolites in American ginseng (Panax quinquefolium), it could be released into soil through root exudation and decomposition during plant growth. This study determined ginsenoside contents in American ginseng cultivated soil by HPLC. Three ginsenosides, Rb1, Rb2 and Rd, were detected in the rhizosphere soil of 3-4 years old American ginseng cultivated in Huairou District, Beijing, and their contents were 0.80-3.19 mg x kg(-1). Correspondingly, the contents of the three ginsenosides in soil solution were 4-16 mg x L(-1) at field water-holding capacity of 20%. According to the field soil test data, we designed the concentration of ginsenosides for bioassays (0.2-125 mg x L(-1) in solution or 0.2-125 mg x kg(-1) in soil). The results showed that radicle lengths of American ginseng were reduced by 6%-23% in solution containing 0.2-125 mg x L(-1) ginsenoside extract, and a significant difference was observed at concentration of 125 mg x L(-1) (P < 0.05). The shoot lengths of American ginseng were not significantly inhibited by 0.2-125 mg x L(-1) ginsenosides extractions. After 20 days of growth in nutrient solution amended with 25 mg x L(-1) ginsenosides extraction, plant height of 3-year-old American ginseng seedling was decreased by 28% compared to the control, and the biomass of aerial parts was also reduced by 50% (P < 0.05). However, the growth of newly-grown fibrous root was not significantly inhibited. Comparatively, when American ginseng embryos were cultivated into sterile or non-sterile soil, neither radicle lengths nor shoot lengths were significantly affected by 0.2-125 mg x kg(-1) ginsenoside extracts. In conclusion, ginsenosides showed autotoxic effect on growth of American ginseng radicle and adult seedling, however, this effect was weakened in field soil.
Chromatography, High Pressure Liquid ; Culture Media ; chemistry ; metabolism ; Ginsenosides ; analysis ; metabolism ; toxicity ; Panax ; chemistry ; drug effects ; growth & development ; metabolism ; Plant Roots ; chemistry ; drug effects ; growth & development ; metabolism ; Soil ; chemistry

Aged ; Female ; Fluorobenzenes ; therapeutic use ; Humans ; Hyperlipidemias ; blood ; drug therapy ; genetics ; Polymorphism, Genetic ; genetics ; Pyrimidines ; therapeutic use ; Rosuvastatin Calcium ; Sulfonamides ; therapeutic use

Objective To observe the changes of microRNA‐214 (miR‐214) expression in rat pulmonary artery smooth mus‐cle cells (PASMCs) induced by different hypoxia time ,and lay the foundation to explore the effect and mechanism of regulation of miR‐214 on PASMCs proliferation .Methods The primary cultured PASMCs were cultured under hypoxic 0 h ,6 h ,12 h ,24 h ,48 h ,respectively .The real time quantitative PCR was used to detect miR‐214 expression in each group PASMCs .Results The ex‐pression of miR‐214 in hypoxia group PASMCs was sustained as time increased ,apart from hypoxic hypoxia 6h group and 0h group ,the expression of miR‐214 was no significant difference (P>0 .05);the expression of miR‐214 among other groups PASMCs was significantly different (P<0 .05) .Conclusion The expression of miR‐214 in PASMCs increased after induction of hypoxia .We speculated that miR‐214 may be involved in the regulation of hypoxia induced PASMCs proliferation .

To design a new method to simulate the micro-motion of human body surface due to respiration and heartbeat, and to provide detection object and calibration signal for the bio-radar technology. Precision lin-ear module was used to transform rotational movement to linear displacement, with AC servo motor to precisely control the module's rotation. Ultimately, ultralow-frequency micro-motion was produced with its displacement being quantitatively controlled. A system simulating the micro-motion of human body surface was newly built. Compared with the old system, the new one produced micro-motion with better constancy, and realized quantitative control of the motion's dis-placement. The method lays technological foundation for simulating the micro-motion of human body surface due to respiration and heartbeat and may promote the development of bio-radar technology towards intensive and compre-hensive levels.

Objective: To learn the concentration of target genes of severe acute respiratory syndrome coronavirus 2 ( SARS-CoV-2 ) and the influencing factors in the confirmed cases with coronavirus disease 2019 ( COVID-19 ) in Ningbo. Methods: Demographic information and clinical diagnosis of COVID-19 cases reported in Ningbo from January 21 to February 20, 2020 were collected through China Disease Control and Prevention Information System. The Ct values of ORF1ab and N of the cases were collected through Ningbo Center for Disease Control and Prevention and designated hospitals, and analyzed in terms of gender, age, severity, clinical classification, source of case, sampling time and specimen type. Results: There were 157 confirmed COVID-19 cases, including 56 males ( 35.67% ) and 101 females ( 64.33% ). Sixty-seven cases ( 42.68% ) aged between 40 and 60 years old. The Ct values of ORF1ab and N in females were 29.96±5.28 and 30.38±4.90, which were higher than 27.56±4.94 and 28.03±4.88 in males ( P<0.05 ). The Ct values of ORF1ab and N were the lowest when sampled at 1-7 days after onset ( P<0.05 ), which were 27.84±4.80 and 28.35±4.65. The Ct values of ORF1ab ( rs=0.288, P=0.001 ) and N ( rs=0.296, P=0.001 ) were positively correlated with sampling time. The Ct values of ORF1ab in pharyngeal swab and sputum were 29.19±4.85 and 28.74±6.40, the Ct values of N in pharyngeal swab and sputum were 29.61±4.60 and 29.22±6.10, both without significant differences between different samples ( P>0.05 ). Conclusions Sampling time has a great influence on the Ct values of ORF1ab and N of SARS-CoV-2.

This study is to evaluate the effects of Shenmai injection on the temporal alterations of action potential (AP), early afterdepolarization (EAD) and delayed afterdepolarization (DAD) in papillary muscles. The action potentials were recorded by a glass electrode. APD at 90% repolarization (APD9 ) was measured, and spontaneous EAD and DAD were observed. The results show APD90 was significantly prolonged in model group compared with sham-operated group, whereas it was remained unchanged in Shenmai injec- tion treatment group and amiodarone group. The spontaneous EADs and DADs were frequently visible in model group. In conclusion, EAD, DAD and trigger activities increase gradually during pathological progression of rat cardiac hypertrophy, and Shenmai injection could improve the action potential change in rat cardiac hypertrophy.
Action Potentials ; drug effects ; Animals ; Blood Pressure ; drug effects ; Cardiomegaly ; physiopathology ; Drug Combinations ; Drugs, Chinese Herbal ; administration & dosage ; pharmacology ; Heart Ventricles ; drug effects ; physiopathology ; Injections ; Male ; Papillary Muscles ; drug effects ; physiopathology ; Rats ; Rats, Sprague-Dawley