Intra-atrial re-entrant tachycardias (IARTs) are common late after heart surgery. Conventional mapping and ablation is relatively difficult because of the complicated anatomy and multiple potential re-entry loops. In this study we aimed to evaluate the electrophysiological characteristics and radiofrequency catheter ablation of atrial tachycardia (AT) induced by myocardial scar or incision. Methods In 6 patients (three male and three female, aged 33.3+ 11.8 years) who had AT related to myocardial scar or incision,electrophysiological study and radiofrequency catheter ablation (RFCA) were performed. Earliest activation combined with entrainment mapping was adopted to determine a critical isthmus. Results Re-entry related to the lateral atriotomy scar was inducible in 5 of6 patients. With entrainment mapping, the PPI (post-pacing interval)-TCL (tachycardia cycle length) difference was ＜30 ms when pacing at the inferior margins of the right lateral atriotomy scar. Among them, 3 patients had successful linear ablation between scar area to inferior vena cava, and 2 patients between scar area to tricuspid annulus. Re-entry involving an ASD patch was demonstrated in 1 of 6 patients. PPI-TCL differences ＜30 ms were observed when entraining tachycardia at sites near the septal patch. But linear ablation failed in terminating AT. There was no complication during procedure. No recurrence of AT related to incision was observed during follow-up except for the failed patient. Conclusion Under conventional electrophysiological mapping, adopting linear ablation from scar area to anatomic barrier, successful ablation can be obtained in patients with IRATs related to myocardial scar or incision.

Objective To compare the safety and effectiveness between ozone (O3) and hyaluronic acid (HA) in treating knee osteoarthritis(KOA) by using the meta analysis method.Methods The relevant randomized controlled trials(RCTs) in PubMed,Cochrane Library (issue 1,2016),Embase,CNKI,CBM,VIP,and Wan-Fang databases were retrieved from their establishment to January 23,2016.Two reviewers independently screened the literatures,extracted the data and evaluated the quality of the included RCTs.The results were performed the statistical analysis by using the RevMan5.3 and Stata13.0 software.Results Twenty RCTs involving 2 136 KOA patients were included.Compared with the HA treatment of KOA,the O3 treatment had higher treatment effective rate[odds ratio(OR) =2.78,P＜0.01],and better pain relief effect[at 1,3,6 month after treatment:mean difference(MD) =-0.25,-0.71,-1.70,P＜0.01].There were no statistically significant differences in complications between the two treatment methods[OR=0.84,P=0.56].Conclusion Current evidences indicate that the short-term therapeutic effect of O3 for KOA is superior to HA,and the safety is similar.

Objective To study the effect and histocompatibility of urethral extracellular matrix in repair of traumatic urethra defects in rabbits. Methods Model of traumatic urethral defects was made by resecting 1.0-1.5 cm segment of the urethra in 20 rabbits. Then, the defects were repaired by a tube of extracellular matrix of the same length. The dynamic changes of CD4+, CD8+ T cell and CD4+/CD8+ in peripheral blood were detected by flow cytometry at 1,2, 3 and 4 weeks after operation. In the meantime, the immunity response of rabbits was evaluated by lymphocyte transformation test. The repaired segments stained with hematoxylin-eosin (HE) and Van Giesen were studied by histologic and pathologic observations at 10 days, 3, 6 and 24 weeks postoperatively. The urodynamics, urethroscopy and urethrography were performed at 24 weeks postoperatively. Results There was no significant difference in aspects of stimulative index of lymphocyte transformation, T lymphocyte subsets CD4+, CD8+ T cell and CD4+/CD8+ between experimental group and negative control group. Urothelium covered the whole surface of the matrix tube three weeks after operation. The smooth muscle cells increased nearly to normal urethral wall at 24 weeks. Urethrosoopy and urethrography showed glossy matrix tube. There was no statistical difference upon urodynamies between experimental group and control group. Conclusion The urethral extracellular matrix has good histocompatibility and may be a safe and effective material for repairing urethra defects.

Objective To study the protective effects of parathyroid hormone (PTH) on radiationinduced hematopoietic damage in mice.Methods A total of sixty male C57 mice were irradiated by 60Co γ-rays to induce hematopoietic injuries,and then the mice were randomly divided into PTH and control group.The PTH-treated group was treated with PTH ( 80 μg· kg- 1 · d - 1 ) intraperitoneally everyday.The control group was given equivalent volume saline.Peripheral blood cell number,bone marrow mononuclear cell number,granulocyte-macrophage colony forming units ( CFU-GM ) and CD34 positive cells in bone marrow were detected.Results With the whole post-irradiation period,the WBC and bone marrow mononuclear cell numbers in PTH-treated mice were significantly higher than those in saline-treated mice (t=6.32,9.19,11.18,7.44 and 4.42,P ＜ 0.05).The RBC numbers in PTH-treated mice were significantly higher than those in control mice at 10 d,15 d and 20 d post-irradiation (t =6.48,3.66 and 4.98,P ＜0.05 ).The PLT numbers in PTH-treated mice were significantly higher than those in control group at 5 and 30 d post-irradiation ( t =2.57 and 3.10,P ＜ 0.05 ).PTH increased CD34 positive cell and CFU-GM numbers in bone marrow after irradiation ( t =16.12,7.82 and 20.00,P ＜ 0.05 ).Conclusions PTH could improve the hematopoietic recovery after irradiation.

Objectives:To investigate the short-term efficacy of oblique lateral interbody fusion(OLIF)in treating mild-to-moderate lumbar spinal stenosis(LSS).Methods:35 patients with mild-o-moderate LSS treated with OLIF between May 2018 and May 2020 were analyzed retrospectively,including 25 males and 10 females,aged 50-74(60.3±10.7)years old.The patients were followed up for 12-28(18.3±3.7)months.The operative time,intraoperative bleeding,and complications were recorded;At preoperation,1 week,and 3,6 and 12 months after surgery,the visual analogue scale(VAS)for lumbar and leg pain and Oswestry disability index(ODI)were compared to evaluate clinical efficacy;And lumbar X-ray,CT,and MRI were performed at the same time to measure and evaluate the height of the intervertebral space,size of intervertebral foramen,area of dural sac and sagittal diameter,lordotic angle of intervertebral space,lordotic angle of lumbar spine,and their respective differences between before and after operation,as well as between each postoperative time point were analyzed;The complications and fusion conditions at each time point were also documented.Results:The operative time was 30-100(70.5±20.3)min,and intraoperative bleeding was 20-120(60.3±20.2)mL.The lumbar and leg pain VAS scores and ODI at postoperative 1 week,and 3,6 and 12 months were signif-icantly improved compared with those before operation,and the differences were statistically significant(P＜0.05),while there was no statistical significance when compared pairwisely between postoperative time points(P＞0.05).At postoperative 1 week,and 3,6 and 12 months,the intervertebral space height,intervertebral lor-dotic angle and lumbar lordotic angle,left and right intervertebral foramina sizes,dural sac areas,and sagittal diameters increased significantly compared with those before operation,with statistically significance(P＜0.05),and no statistical difference was found when compared pairwisely between postoperative time points for each imaging parameter(P＞0.05).According to the CT image evaluation 1 year after operation,the overall fusion rate was 94.2％(33/35 cases).No serious complications such as nerve and vascular injury occurred;3 cases of postoperative hip flexion weakness and anterior thigh numbness were relieved after 1 month of symptomatic treatment with conservative therapy;2 cases of fusion device sinking of end-plate cutting were revised in the second stage and underwent posterior muscular gap approach internal fixation.Conclusions:OLIF has satisfactory short-term clinical efficacy in the treatment of mild-to-moderate LSS.

The article reports a rare case of isolated persistent left superior vena cava (PLSVC) found during the catheterization of a dialysis catheter in an end-stage renal disease patient and the occurrence of guidewire entrapment in Chiari net. The patient was scheduled to have emergency dialysis due to end-stage renal disease and acute left heart failure. And a tunnel-cuffed catheter (TCC) for dialysis insertion was planned. Isolated PLSVC was found firstly by the imaging process. Then the guidewire was entrapped at the right atrium in the further operation. During the operation of the guidewire, the guidewire loosened and withdrawn with a fine fiber, which was considered a possibility of Chiari net. In the follow-up after one week, the TCC worked well, and the heart function improved after dialysis.

Objective To explore the feasibility and effect of 3D modeling and printing technology in constructing bone fracture models and assisting clinical teaching at the department of traumatic orthope-dics. Methods CT scan images of bone fractures were reconstructed by Mimics software. The digital 3D bone fracture models were constructed and the interactive multimedia teaching videos were output. More-over, all bone fracture models were printed by using fusion deposition modeling (FDM). At the end of the teaching course, a questionnaire survey was conducted to evaluate the teaching effect. Results The digital models of common bone fractures at the department of traumatic orthopedics were established, and the in-teractive multimedia teaching videos were output. A traumatic orthopedic teaching model with a 1∶1 scale was printed out. The questionnaire survey indicated that the application of 3D modeling and printing tech-nology to build bone fracture model with PPT teaching can obviously improve students' understanding and mastery of relevant theoretical knowledge. They helped students better remember the type of bone fractures and how to choose the correct internal fixation methods. The teaching effect was satisfactory. Conclusions 3D modeling and printing technology was applied to build bone fracture models to assist clinical teaching at the department of traumatic orthopedics. It was found that the printed 3D bone fracture models can stimulate students' enthusiasm for learning and improve their learning effect. This method has good application value.

Renal replacement therapy and perioperative management have difficulties in hemophilia patients with end-stage renal disease. The paper summarized the diagnosis and treatment experience of six hemophilia patients complicated with end-stage renal disease from January 1, 2000 to March 31, 2023 in Peking Union Medical College Hospital. Among 6 patients treated with peritoneal dialysis, 3 were treated with hemodialysis or continuous venous-venous hemodialysis. Altogether 11 dialysis access procedures were conducted successfully, and no serious bleeding or thrombotic events. In further conjunction with literature review, the paper summarized the key points of dialysis access appliance relevant to such patients, to provide reference for renal replacement treatment paths.

OBJECTIVETo observe the effects of electroacupuncture(EA) at different acupoints for fasting blood glucose(FBG) and oral glucose tolerance in type 2 diabetes rats so as to verify the glucose-lowering effects of EA.

METHODSTotal 100 SD male rats were seen as experimental objects,among which 13 were randomly assigned into a blank group. Other rats were fed with high fat and high sugar diet combined with intraperitoneal injection of small dose streptozotocin (STZ) to establish type 2 diabetes model. Sixty diabetic rats were randomly assigned into a model group,a Weiwanxiashu group,a Xinshu group,a Shenshu group and a Housanli group,12 cases in each one. Combined with the improved diet habits and routines,EA (2 Hz and 2 mA) was used at "Weiwanxiashu" (EX-B 3),"Xinshu" (BL 15),"Shenshu" (BL 23) and "Housanli" (ST 36) in the corresponding groups,6 times a week for 4 weeks. There was no treatment in the blank group and in the model group. The observation indexes were the FBG on the 7th,14th,21st,and 28th day of intervention,the instant glucose-lowering effect on the 21st day during treatment,and the area under the curve of oral glucose tolerance test (OGTT) after intervention. Also,the glucose regulation condition was observed.

RESULTSType 2 diabetes model could be established by high fat and high sugar diet combined with intraperitoneal injection of small dose STZ. Glucose decreased apparently at the end of the 1st week or the 2nd week compared with that before treatment in the Weiwanxiashu,Xinshu and Shenshu groups(<0.05,<0.01). The instant FBG of the Weiwanxiashu and Xinshu groups was obviously lower than that of the model and Housanli groups at the end of the 3rd week(all<0.01). The area under the curve of OGTT of the Weiwanxiashu group was apparently smaller than that of the model group (<0.05),and the results of the index in the other groups were not significantly different from that of the model group(all>0.05).

CONCLUSIONSLow frequency EA at "Weiwanxiashu"(EX-B 3),"Xinshu"(BL 15) and "Shenshu"(BL 23) can reduce glucose with different onset times,effects,and durations. And "Weiwanxiashu"(EX-B 3) is more effective.

Artificial Intelligence ; Forecasting ; Humans ; Rare Diseases ; Urinary Bladder Neoplasms/diagnosis*