BACKGROUND:"Tendon off-position"is a disease name included in the International Classification of Diseases 11th Revision,and also a clinical indication of manipulation,acupuncture and other treatments.However,its specific mechanism is still unclear.It is urgent to establish an animal model that can reflect the clinical and pathological characteristics of"tendon off-position,"so as to further study the mechanism of effective clinical treatments. OBJECTIVE:To establish an animal model of"tendon off-position"in rats based on isometric contraction of skeletal muscles,and to explore the changes of skeletal muscle function and morphological phenotype after"tendon off-position." METHODS:Sixty rats were randomly divided into control group,static-loading group and extra loading group,with twenty rats in each group.Rats in the control group were kept normally without treatment.In the latter two groups,the rats were fixed by the self-made static-loading modeling device and a static-loading(the body mass of each rats was applied as the static-loading)was applied to cause sustained isometric contraction of the upper limb muscles.Then,animal models of"tendon off-position"were successfully established.In the extra loading group,50%of the body mass was added to the ankle joint after modeling.The skeletal muscle samples were harvested at 2 and 4 weeks after modeling.The changes of limb grip strength,wet mass of skeletal muscle,and serum levels of creatine kinase-muscle and lactate dehydrogenase A were measured,and the changes of skeletal muscle histomorphology and ultrastructure were observed. RESULTS AND CONCLUSION:At 2 weeks after modeling,the rats in the static-loading group and extra loading group showed significantly decreased grip strength and wet muscle mass,significantly increased serum levels of creatine kinase-muscle and lactate dehydrogenase A,and abnormal muscle fiber morphology and structure accompanied by a large number of deposited collagen fibers.Electron microscopy results showed that the structure of myofibrils was disordered,the Z-line was distorted,and the light and dark boundaries were blurred.At 4 weeks after modeling,the grip strength of the model rats was increased compared with that at 2 weeks,the serum creatine kinase-muscle and lactate dehydrogenase A levels were decreased,and the changes of muscle fiber morphology and ultrastructure were recovered to varying degrees.It is suggested that the rat skeletal muscle injury model based on continuous isometric contraction of skeletal muscle can well reflect the pathological characteristics of"tendon off-position"at 2 weeks,and can be used to study the mechanism of acupuncture and manipulation in the treatment of"tendon off-position."

Objective:To investigate the correlation between CHA 2DS 2-VASC score and the recurrence risk of paroxysmal atrial fibrillation after radiofrequency ablation. Methods:It was a retrospective cohort study. A total of 150 patients who underwent radiofrequency ablation for paroxysmal atrial fibrillation in Xingtai People′s Hospital from January 2017 to January 2021 were consecutively included in the study. According to the preoperative CHA 2DS 2-VASC score, patients were divided into high score group (≥3 points, n=90) and low score group (<3 points, n=60). Baseline clinical data was collected. All patients underwent circumferential pulmonary vein isolation, and those with atrial flutter before ablation also underwent tricuspid isthmus isolation. Holter and electrocardiogram examinations were performed at 3, 6 months and 1 year after ablation to evaluate whether there was recurrence of atrial fibrillation. Univariate and multivariate Cox regression was used to analyze the risk factors for recurrence of atrial fibrillation after radiofrequency ablation. Results:Among 150 patients 90 were males and 60 were females with a mean age of (64.0±3.6) years. There were no significant differences in age, sex, and proportion of hypertension, diabetes, chronic heart failure and stroke or transient ischemic attack (TIA), medication of antiarrhythmic and anticoagulant drugs between the two groups (all P>0.05). The longest duration of atrial fibrillation in the high score group was significantly longer than that in the low score group (26.0±6.1) hours vs. (10.0±2.1) hours, P<0.05). There were no patients with cardiac tamponade, atrial esophageal fistula and severe vascular puncture complications in the two groups. During the follow-up period, the recurrence rate in the high score group was significantly higher than that in the low score group (16.7% (15/90) vs. 8.3% (5/60), P<0.05). Multivariate Cox regression analysis showed that CHA 2DS 2-VASC score≥3 was an independent risk factor for atrial fibrillation recurrence in patients with paroxysmal atrial fibrillation after radiofrequency ablation ( HR=3.84, 95% CI: 1.87-7.89, P=0.02). Conclusion:CHA 2DS 2-VASC score≥3 is an independent risk factor for atrial fibrillation recurrence in patients with paroxysmal atrial fibrillation after radiofrequency ablation.

Objective To investigate the value of polar residual network(PResNet)model for assisting evaluation on rat myocardial infarction(MI)segment in myocardial contrast echocardiography(MCE).Methods Twenty-five male SD rats were randomly divided into MI group(n=15)and sham operation group(n=10).MI models were established in MI group through ligation of the left anterior descending coronary artery using atraumatic suture,while no intervention was given to those in sham operation group after thoracotomy.MCE images of both basal and papillary muscle levels on the short axis section of left ventricles were acquired after 1 week,which were assessed independently by 2 junior and 2 senior ultrasound physicians.The evaluating efficacy of MI segment,the mean interpretation time and the consistency were compared whether under the assistance of PResNet model or not.Results No significant difference of efficacy of evaluation on MI segment was found for senior physicians with or without assistance of PResNet model(both P＞0.05).Under the assistance of PResNet model,the efficacy of junior physicians for diagnosing MI segment was significantly improved compared with that without the assistance of PResNet model(both P＜0.01),and was comparable to that of senior physicians.Under the assistance of PResNet model,the mean interpretation time of each physician was significantly shorter than that without assistance(all P＜0.001),and the consistency between junior physicians and among junior and senior physicians were both moderate(Kappa=0.692,0.542),which became better under the assistance(Kappa=0.763,0.749).Conclusion PResNet could improve the efficacy of junior physicians for evaluation on rat MI segment in MCE images,shorten interpretation time with different aptitudes,also improve the consistency to some extent.

Objective:To compare the efficacy of high density grid mapping catheter (HD-Grid) and circular mapping catheter in the ablation of paroxysmal atrial fibrillation.Methods:Patients with paroxysmal atrial fibrillation undergoing radiofrequency ablation in Xingtai People′s Hospital from March 2020 to March 2021 were randomly divided into the HD-Grid group and the circular mapping catheter group. The baseline data, operation time, X-ray exposure time, pulmonary vein isolation time, recovery of pulmonary vein conduction, the number of recovery sites, and perioperative complications were compared between the two groups. The patients were followed up at 1, 3, 6 and 12 months after operation, and a continuous electrocardiogram was performed to evaluate recurrence of atrial fibrillation.Results:Sixty patients were enrolled in the study with 30 cases in each group, including 33 males and 27 females with an average age of 63.0 (57.0, 70.3) years. There were no significant differences in age, gender ratio, comorbidity proportion, CHADS 2-VASC score, history of atrial fibrillation, B-type natriuretic peptide level, and left atrial diameter between the two groups (all P>0.05). The operation time of the HD-Grid group was longer than that of the circular mapping catheter group ((136.6±7.7) minutes vs. (127.5±7.7) minutes, P<0.001). During the observation period, 8 cases (26.67%) with pulmonary venous conduction recovery were identified in the HD-Grid group, which was higher than that in the circular mapping catheter group (2 cases(6.67%)) ( P=0.038). Eighteen (60.00%) pulmonary vein reconnection sites were identified in the HD-Grid group, which were more than that in the circular mapping catheter group (2 sites(6.67%), P=0.013). There was no significant difference in X-ray exposure time and pulmonary vein isolation time between the two groups (both P>0.05). There was no significant difference in the proportion of patients taking anticoagulant drugs and antiarrhythmic drugs during the perioperative period between the two groups (both P>0.05). No serious complications such as cardiac tamponade, phrenic nerve injury, pulmonary embolism, cerebral infarction and death occurred in both groups. During the follow-up period, 1 patient (3.33%) in the HD-Grid group had recurrence of atrial fibrillation, while 5 patients (16.67%) in the circular mapping catheter group had recurrence of atrial fibrillation, but there was no significant difference between the two groups ( P=0.197). Conclusions:HD-Grid for radiofrequency ablation of paroxysmal atrial fibrillation improves the identification rate of pulmonary vein potentials and pulmonary vein reconnection sites, and it may reduce the recurrence rate of atrial fibrillation. Although the operation time was prolonged, it would not increase the risk of perioperative complications.

Osteoporotic vertebral compression fracture (OVCF) can lead to lower back pain and may be even accompanied by scoliosis, neurological dysfunction and other complications, which will affect the daily activities and life quality of patients. Vertebral augmentation is an effective treatment method for OVCF, but it cannot correct unbalance of bone metabolism or improve the osteoporotic status, causing complications like lower back pain, limited spinal activities and vertebral refracture. The post-operative systematic and standardized rehabilitation treatments can improve curative effect and therapeutic efficacy of anti-osteoporosis, reduce risk of vertebral refracture, increase patient compliance and improve quality of life. Since there still lack relevant clinical treatment guidelines for postoperative rehabilitation treatments following vertebral augmentation for OVCF, the current treatments are varied with uneven therapeutic effect. In order to standardize the postoperative rehabilitation treatment, the Spine Trauma Group of the Orthopedic Branch of Chinese Medical Doctor Association organized relevant experts to refer to relevant literature and develop the "Guideline for postoperative rehabilitation treatment following vertebral augmentation for osteoporotic vertebral compression fracture (2022 version)" based on the clinical guidelines published by the American Academy of Orthopedic Surgeons (AAOS) as well as on the principles of scientificity, practicality and advancement. The guideline provided evidence-based recommendations on 10 important issues related to postoperative rehabilitation treatments of OVCF.

Objective:To evaluate the feasibility of a new ultrasonic parameter to assess right ventricular-pulmonary artery (RV-PA) coupling in patients with acute pulmonary embolism (APE).Methods:A retrospective analysis was performed in 140 patients with APE diagnosed by computed tomography pulmonary angiography (CTPA) in the Second Affiliated Hospital of Harbin Medical University from August 2017 to June 2020. According to the tricuspid annular plane systolic excursion/pulmonary arterial systolic pressure (TAPSE/PASP) ratio cutoff value 0.40 mm/mmHg reported by the European Society of Cardiology in 2020, the patients were divided into the coupling group ( n=99) and the uncoupling group ( n=41). The conventional ultrasonic parameters of the 2 groups were measured, and then several ultrasonic parameter ratios were obtained. The new ultrasonic parameter, which can replace the TAPSE/PASP ratio, was screened out by Spearman correlation analysis, and ROC curve was plotted to calculate the diagnostic efficacy of this parameter. Results:①Compared with the coupling group, patients in the uncoupling group were older and more likely to be accompanied by dyspnea and venous thrombosis in the lower extremities (all P<0.05), but there was no significant difference in other general data(all P>0.05); ②Compared with the coupling group, tricuspid regurgitation velocity (TRV), tricuspid regurgitation pressure gradient(TRPG), PASP, right ventricle end-diastolic transverse diameter(RVTD), inferior vena cava(IVC) diameter and the ratio of early diastolic tricuspid inflow to tricuspid lateral annular velocity(E/e′), in the uncoupling group increased significantly (all P<0.05), and TAPSE, peak systolic velocity of tricuspid annulus(s′), TAPSE/PASP ratio, TAPSE/TRPG ratio, TAPSE/RVTD ratio and s′/TRPG ratio decreased significantly (all P<0.05); ③The TAPSE/TRPG ratio was highly correlated with TAPSE/PASP ratio ( rs=0.970, P<0.001); The TAPSE/TRPG ratio was still highly correlated with TAPSE/PASP ratio in the uncoupling and coupling groups ( rs=0.966, 0.922; all P<0.001). ④ROC analysis showed that the area under curve for TAPSE/TRPG in diagnosing RV-PA coupling was 0.992. At the cutoff of TAPSE/TRPG <0.625 mm/mmHg for indicating RV-PA coupling, the sensitivity and specificity were 97.6% and 92.9%, respectively. Conclusions:TAPSE/TRPG ratio can be used as a new ultrasonic parameter to reflect RV-PA coupling, which is helpful for clinical identification of APE patients with high risk and poor prognosis.

Objective:To analyze the clinical characteristics of fulminant type 1 diabetes (FT1DM) in China.Methods:Clinical data of 279 cases related to FT1DM in Chinese Database from January 2005 to December 2018 were collected, and other 20 patients from our hospital were included in the present study.Results:(1) There has been a progressive increasing in the number of reported cases every year in China, and the number in the southern region were significantly more than that in the northern region. (2) The median age of the onset of FT1DM patients in China was 32.5 years old, without significant gender difference. Moreover, 36.5% (54/148) of the female patients caught the disease during their prenatal period, most of them were onset in the second or third trimesters of pregnancy and 2 weeks after delivery (37/40), and the prognosis of the fetus was extremely poor. (3) Compared with new-onset type 1 diabetes, FT1DM patients were younger, and with higher blood glucose [(39.7±15.3) vs (21.2 ± 9.9) mmol/L], higher serum creatinine [(188.4±115.9) vs (51.8 ±23.1) μmol/L], and higher amylase levels [245.5 (26.0-5 137.0) vs 54.7 (14.0-404.9) U/L]. FT1DM patients were with more severe acidosis, and lower HbA 1C level [(6.6 ±0.8)% vs (12.9 ± 2.5)%, P<0.01]. (4) FT1DM patients may combine with multiple organ dysfunction or severe metabolic disorders, electrolyte disorders, as well as liver and kidney dysfunctions, and elevation of amylase and muscle enzymes. Conclusion:FT1DM are with some clinical characteristics different from classic new-onset type 1 diabetes, including adult-onset, frequent in the southern China. Pregnancy may be a predisposing factor for female patients. Significant metabolic disorders and multiple organ involvements are common in the patients with FT1DM.

Objective:To investigate the safety and efficacy of sacral neuromodulation(SNM)therapy for the treatment of lower urinary tract dysfunction(LUTD)in elderly patients.Methods:Clinical data of 91 elderly patients with LUTD from multiple medical institutions who received SNM during the period from January 2012 to December 2016 were retrospectively analyzed.Patients were divided into four groups: the interstitial cystitis(IC)group(n=28), the neurogenic bladder(NB)group(n=36), the overactive bladder syndrome(OAB)group(n=13)and the idiopathic dysuria(ID)group(n=14). Different sets of evaluation parameters were used for different diseases.Patients’ baseline data and data in stage I(test phase)and stage Ⅱ(permanent SNM)were recorded, statistically analyzed and compared.Results:Ninety-one people underwent SNM treatment.Of them, 53 patients received permanent implants(stage Ⅱ), and the total conversion rate of stage I to stage Ⅱ was 58.2%(53/91). Patients receiving permanent implants(stage Ⅱ)had a preoperative period ranging from 3 months to 30 years, and were followed up for 2 to 58 months after treatment, with an average follow-up of 19.6 months.The improvement rates in stage I for urinary urgency, daily urination frequency, daily nocturnal urination frequency, maximum urine volume, daily average urine volume, daily urine leakage frequency, and quality of life score were 35.4%, 31.6%, 33.7%, 32.6%, 49.2%, 43.2% and 13.2%, respectively.The improvement rates in stage Ⅱ for urinary urgency, daily urination frequency, daily nocturnal urination frequency, maximum urine volume, daily average urine volume, daily urine leakage frequency, and quality of life score were 43.2%, 40.0%, 37.8%, 50.5%, 70.5%, 70.4% and 43.2%, respectively.Three adverse events occurred, including 1 case of recurrent symptoms, 1 case of moderate infection, and 1 case of electrical lead dislocation.Conclusions:Sacral nerve stimulation has definitive and consistent curative effects on LUTD in elderly people.The follow-up time should be extended to further study the safety of sacral nerve stimulation.

This article reported a case of malignant pheochromocytoma and paraganglioma with cranial metastasis. The patient was a 25-year-old man. At the age of 10, he was diagnosed with retroperitoneal paraganglioma. He received radiotherapy after partial resection of the tumor. At the age of 15, when he consulted for headache and hypertension, a space occupying lesion was found on the right adrenal without further diagnosis and treatment. His headache and hypertension were aggravated at the age of 25. Then he visited our medical center and diagnosed with right adrenal pheochromocytoma. He undertook an operation to remove the right adrenal lesion, and his blood pressured could be controlled in the normal range with oral antihypertensive medication. One year after the surgery, a cranial lesion with positive 131I-metaiodobenzylguanidine imaging was found following the increase of norepinephrine and dopamine in both blood and urine. The diagnosis of malignant pheochromocytoma with cranial metastasis was confirmed. The cranial lesion was treated with cyberknife therapy for 4 times, and the lesion was slightly reduced. Four year after the removal of right adrenal tumor, he developed multiple bone metastasis in the right ribs and left ilium, and then he received 131I-metaiodobenzylguanidine radiotherapy. Additionally, the results of gene test indicated a pathogenic mutation of SDHB. During the follow-up period of one year after the treatment, his blood pressure fluctuated to about 140/90mmHg with 10mg of phenoxybenzamine once a day. The case is a malignant pheochromocytoma with multiple bone metastasis characterized by a long course with an ideal prognosis in a way. Consequently, we suggested the diagnostic pathway with genetic testing based on clinical phenotype to approach more timely diagnosis and reasonable evaluation of the prognosis in pheochromocytoma and paraganglioma. Furthermore, clinicians should pay more attention to the long-term surveillance.

Objective:To explore the application value of a novel ultrasonic scale in the evaluation of sub-massive pulmonary embolism (sub-PE).Methods:Retrospective analyses were conducted in 137 patients with acute pulmonary embolism confirmed by computed tomography pulmonary angiography (CTPA) in the second affiliated hospital of Harbin Medical University from September 2017 to June 2019. They were divided into experimental set (77 cases) and testing set(60 cases). According to the European Society of Cardiology (ESC) guidelines for pulmonary embolism in 2019, the patients were classified into sub-PE(71 cases) and small pulmonary embolism(small-PE, 66 cases). Parameters in the experimental set were screened by statistical methods to make an ultrasonic scale, and then the patients in the testing set were scored by the scale. ROC curve was plotted to calculate the diagnostic efficacy of the ultrasonic scale for sub-PE.Results:①The patients of sub-PE were older than small-PE patients [(61.57±1.45) years vs (56.31±1.59) years, P=0.016], but there was no significant difference between the two groups in other general data( P>0.05). ②Within the 77 pulmonary embolism patients in the experimental set, 41(53.25%) were classified as the sub-PE and 36(46.75%) as the small-PE. Compared with the small-PE group, right ventricular diameter, pulmonary artery trunk diameter, right ventricle/left ventricle ratio, tricuspid regurgitation velocity, the Tei index and the inferior vena cava diameter in the sub-PE group increased significantly ( P<0.05), and right ventricular wall motion amplitude, right atrium area rate, right ventricular area rate, tricuspid annulus systolic displacement, collapse rate of inferior vena cava and pulmonary artery blood flow acceleration time decreased significantly ( P<0.05); ③Fifteen ultrasonic parameters were used in the ultrasonic scale. The scale in sub-PE group of the testing set was significantly increased compared with that in small-PE group (11.63±3.87 vs 4.43±1.96, P<0.001). ROC showed that the AUC in diagnosing sub-PE by ultrasonic scale was 0.96. When the cut-off value was 6.5, the sensitivity and specificity were 90.00% and 83.33%, respectively. Conclusions:The novel ultrasonic scale can provide a comprehensive and feasible ultrasound imaging method for evaluation of sub-PE.