Construction and Evaluation of End-to-side Anastomosis Model of Autologous Arteriovenous Fistula in Mice / 实验动物与比较医学

ObjectiveTo establish an animal model of autologous arteriovenous fistula in mice and evaluate its effect. MethodsThe left external jugular vein and common carotid artery of 10 8-week-old male C57BL/6 mice were separated by end-to-side anastomosis of external jugular vein and common carotid artery after anesthesia, and the right jugular vein was exposed without suture as a control, so as to establish an animal model of internal arteriovenous fistula. Doppler ultrasound, HE and Masson staining and immunohistochemical staining were used to observe the hemodynamics, intimal hyperplasia and protein expression of smooth muscle cell proliferation in the outflow vein of the internal arteriovenous fistula and the contralateral control vein, and to evaluate the effect of model construction. ResultsA total of 10 mice were selected for this study, and 9 mice were successfully modeled, with a success rate of 90%. Ultrasound examinations were performed on the day of surgery, 7 and 14 days after surgery, respectively. The results showed that the flow velocity near the anastomosis was linearly correlated with the diameter of the tube. The higher the flow velocity, the larger the diameter of the tube. There was a positive correlation between peak velocity and lumen diameter (P=0.000 6, R2=0.831 7). After surgery 14 days, HE staining results showed that after autologous arteriovenous fistula molding, the average lumen area of outflow segment vein was significantly decreased (P < 0.000 1), the intima area was significantly increased (P < 0.000 1), the intimal area was significantly increased (P < 0.000 1). On the surgical side of arteriovenous fistula, collagen deposition was significantly increased, and the proportion of Masson-positive regions was significantly increased (P < 0.000 1). Immunohistochemical staining showed that the proportion of collagen 1 positive areas on the surgical side of arteriovenous fistula was significantly upregulated (P < 0.000 1), and α-smooth muscle actin (α-SMA) , proliferating cell nuclear antigen (PCNA) positive cells increased significantly (P < 0.000 1), indicating an increase in local cell proliferation level. ConclusionThe established mouse autologous arteriovenous fistula model has the advantages of high success rate, good stability and low cost. The model provides a good carrier for exploring the biological mechanism of intimal hyperplasia in arteriovenous fistulas.

Comparison on the clinical characteristics of patients with Takotsubo syndrome from China and from Europe/North America / 中华心血管病杂志

Objective: To summarize the clinical characteristics of patients with Takotsubo syndrome (TTS) from China and compare these features with patients from Europe/North America. Methods: We reviewed case reports published between 1990 and 2020 with the key words of "Takotsubo syndrome" "stress cardiomyopathy" "apical balloon syndrome" and "broken heart syndrome", in Wanfang, CNKI, Pubmed and Web of Science databases, and 1 294 articles were identified, including 128 articles reporting 163 cases in China and 1 166 articles reporting 1 256 cases in Europe/North America. The characteristics of demographics, triggers, symptoms, electrocardiogram, echocardiography, left ventriculogram,coronary angiography, treatment and prognosis were analyzed and compared between Chinese and European/North American cases. Results: A total of 1 294 articles (1 419 cases: 163 from China, 1 256 from Europe/North America) were included in the final analysis. The characteristics of Chinese cases included: (1) demographic:the age was (59.6±16.9) years, which was similar with that of European/North American ((59.7±17.4) years, P=0.90), and female accounting for 78.5% (128/163), which was lower than that of European/North American (85.4% (1 073/1 256), P=0.02). (2) Triggers:mental triggers accounted for 48.5% (79/163), physical triggers accounted for 43.6% (71/163), and no triggers accounted for 7.9% (13/163), respectively. Compared with Europe/North America, the ratio of patients with mental triggers was higher in China, while the ratio of patients with physical triggers and no triggers was lower (P<0.05). (3) Symptoms: chest pain (52.8% (86/163)), chest tightness (35.0% (57/163)), shortness of breath (33.1% (54/163)), dizziness (16.0% (26/163)), sweating (15.3% (25/163)), palpitations (12.3% (20/163)), syncope (9.2% (15/163)) abdominal pain/diarrhea (8.6% (14/163)), hypotension (7.4% (12/163)), and fatigue (1.2% (2/163)) were illustrated in sequence. Compared with patients in Europe/North America, the ratio of patients with chest tightness, dizziness, sweating, palpitations, abdominal pain/diarrhea was higher in Chinese patients, while the ratio of patients with hypotension was lower in Chinese patients (P<0.05). (4) Electrocardiogram: main manifestations were myocardial ischemia symptoms, such as ST-segment elevation (63.8% (104/163)), T wave inversion (46.0% (75/163)), ST-segment depression (8.6% (14/163)). Compared with European/North American, the ratio of patients with ST-segment elevation, T wave inversion, and atrioventricular block was higher in Chinese patients (P<0.05). (5) Echocardiography and imaging:apical dyskinesia (59.5% (97/163)) and apical/left ventricular bulbar dilation (36.2%(59/163)) dominated the echocardiography findings. Compared with European/North American, the ratio of patients with apical dyskinesia, apical/left ventricular bulbar dilation, and mitral regurgitation was higher in Chinese patients, while the ratio of patients with dyskinesia in other parts and left ventricular ejection fraction<50% was lower in Chinese patients (P<0.05). Left ventricular angiography showed 36.2% (59/163) of apical dyskinesia in Chinese patients, which was higher than that reported in European/North American patients, and 38.7% (63/163) of apical/left ventricular bulbar dilation was reported in Chinese patients, which was similar to that reported in European/North American patients. Coronary angiography showed percent of no stenosis or stenosis less than 50% was 87.1% (142/163), which was similar to that reported in European/North American patients (P>0.05). The typical type of TTS accounted for 96.3% (157/163), which was significantly higher than that reported in European/ American patients, while the ratio of basal type and midventricular type was lower (P<0.01). (6) Treatment and prognosis:the applied drugs in China were listed in order as following, β-blockers (41.1% (67/163)), antiplatelet agents (37.4%(61/163)), ACEI/ARB (36.2%(59/163)), anticoagulants (27.0%(44/163)), diuretics (19.6% (32/163)), etc. Compared with Europe/North America, the ratio of antiplatelet agents, anticoagulants, statins, diuretics, and nitrates use was higher in China (P<0.05), while the use of oxygen therapy and IABP was similar (P>0.05). The hospital mortality in China was 5.5% (9/163), during 1-year follow-up the recurrence rate was 3.7% (6/163) and the mortality was 0. The prognosis was similar with that in Europe/North America. Conclusions: Compared with TTS cases in Europe/North America, TTS cases in China also occur usually in middle-aged and elderly women, most of whom have mental/physical triggers and typical imaging manifestations, followed by a low hospital mortality rate and recurrence rate.

Effects of tongfu decoction on rats' rapid gastric emptying / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To observe the effects of Tongfu Decoction (TFD) on the gastric emptying of normal rats, thus exploring whether it could promote gastric emptying rapidly.</p><p><b>METHODS</b>Thirty Sprague-Dawley (SD) rats were randomly divided into 3 groups, i.e., the normal control group, the domperidone group, and the TFD group, 10 in each group. They were respectively administered with normal saline, the domperidone suspension, and TFD by gastrogavage. Thirty min later the gastric emptying of mice was detected by single photon emission computed tomography technology (SPECT) labeled with 99m Tc-DTPA, and the gastric half-emptying time and the gastric emptying rate were calculated.</p><p><b>RESULTS</b>The gastric half-emptying time was (19.0 +/-1.7) min in the normal control group, (12.9 +/- 3.4) min in the domperidone group, and (12.7 +/- 4.1) min in the TFD group. Compared with the normal control group, the gastric half-emptying time was significantly shortened in the domperidone group and the TFD group (P <0.05). The gastric emptying rate at 15 min was 41.1% +/- 5. 8% in the normal control group, 52.9% +/- 10.9% in the domperidone group, and 56.0% +/- 10.3% in the TFD group, while at 30 min it was 65.6% +/- 2.8%, 72.9% +/- 2.6%, and 72.4% +/- 4.9%, respectively. Compared with the normal control group, the gastric emptying rate at 15 min and 30 min both significantly increased in the domperidone group and the TFD group (P <0.05). There was no statistical difference in the gastric half-emptying time or the gastric emptying rate between the two groups (P >0.05).</p><p><b>CONCLUSION</b>TFD showed similar effects as domperidone in rapidly promoting gastric emptying, and could shorten the gastric half-emptying time in normal rats.</p>

Influence of Wenxin particle on cardiac electrophysiology in depressed rats after myocardial infarction / 心血管康复医学杂志

Objective: To investigate influence of Wenxin particle on cardiac electrophysiology in rats complicated with depression after myocardial infarction (MI). Methods: A total of 50 SD rats were randomly and equally divided into normal group, MI group, depression group, MI complicated with depression group (model group) and Wenxin particle group (Wenxin particle were given to model rats by gavage, 2 g/d, 28d). Model（MI complicated with depression）rats were made by acute ligation of left coronary artery and supply chronic unpredictable mild stress in order. The influences of Wenxin particle on cardiac electrophysiological indexes, such as monophasic action potential (MAP90), left ventricular effective refractory period (ERP) and ventricular fibrillation threshold (VFT) were evaluated in Wenxin particle group. Results: (1) Compared with normal group, there were significant decrease in behavior scores (P<0.05) in model group, after four-week treatment with Wenxin particle, their behavior scores significantly increased (P<0.01); (2) Compared with normal group, there were significant increase in MAPD90 and ERP, and significant decrease in VFT in model group (P<0.05); compared with model group, there were significant decrease in MAPD90 [(89.33±7.12) ms vs. (72.29±8.37) ms] and ERP [(84.00±6.57) ms vs. (68.00±7.43) ms], and significant increase in VFT [(7±3.11)V vs. (29±5.60)V] in Wenxin particle group, P<0.05. Conclusion: Wenxin particle can improve cardiac electrical remodeling in rats complicated with depression after myocardial infarction, including decrease monophasic action potential duration and effective refractory period, and raise ventricular fibrillation threshold.

Impact of abnormal myoelectricity at gastroduodenal anastomosis on gastric emptying in rats / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To explore the impact of abnormal myoelectricity at gastroduodenal anastomosis on gastric emptying in rats.</p><p><b>METHODS</b>Rats were randomly divided into experimental group (n=16) and control group (n=16). Pylorectomy and end-to-end gastroduodenal anastomosis were performed in the experimental group and electrodes were implanted in the serosal surface adjacent to the anastomosis. Slow waves were recorded by the implanted electrode in vivo. Gastric emptying was examined by scintigraphy.</p><p><b>RESULTS</b>At the first week after surgery, antral slow-wave frequency was significantly lower in the experimental group (0.8±1.4 vs. 3.3±1.2, P<0.01), as was the duodenal slow-wave frequency (2.1±0.6 vs. 11.1±0.7, P<0.01). There was no consecutive slow-waves transduction across the pylorus or the anastomosis. Within 12-16 weeks after operation, antral slow-wave frequency in the experimental group and the control group were (8.7±0.6) cpm and (4.0±0.4) cpm, respectively (P<0.01), and duodenal slow-wave frequency were (11.1±0.8) cpm and (10.8±0.7) cpm, respectively (P>0.05). Retrograde and antegrade myoelectricity transduction through the anastomosis were detected. The mean semi-emptying time in the proximal stomach was 14.7 min in the experimental group and 13.6 min in the control group (P>0.05). Radionuclide retention rate was 25.4% in the experimental group and 39.4% in the control group (P>0.05). The mean semi-emptying time in the distal stomach was 25.3 min in the experimental group and 10.5 min in the control group (P<0.01). Radionuclide retention rate was 46.4% in the experimental group and 18.7% in the control group (P<0.01).</p><p><b>CONCLUSION</b>The abnormal myoelectricity in the region of gastroduodenal stoma may delay liquid gastric emptying in pylorectomy rats.</p>