Objective To evaluate the clinical value of speckle tracking imaging in the measurement of two-dimensional strain in patients with myocardial infarction. Methods High frame rate two-dimensional echocardiography were performed in 30 healthy subjects,21patients with anterior myocardial infarction and 15 patients with inferior myocardial infarction. Longitudinal strain (LS), radial velocity (Vs), regional shortening fraction (RFS),radial strain (RS) were measured in the apical two-chamber view and short-axis view(the level of papillary muscle) using two-dimensional strain software. Results Compared with healthy subjects, LS, Vs, RFS, RS decreased in the segments with infarction(P<0.05). LS, Vs, RFS, RS of the two myocardial infarction groups had partly differences(P<0.05). Conclusions Regional wall motion of left ventricle in patients with myocardial infarction can be evaluated accurately with speckle tracking imaging.

We conducted purification of filamentous temperature-sensitive protein Z of Streptococcus suis serotype 2 (S.suis 2) and measured its GTPase activity.The ftsz gene in the genome of the Chinese 05ZYH33 strain of S.suis 2 was successfully amplified using PCR,and then the ftsz gene was cloned into prokaryotic expression plasmid pET28a,and the recombinant plasmid pET28a-ftsz was transformed into E.coli BL21.After induction by IPTG,the isolated FtsZ protein was analyzed with SDS-PAGE.Then the recombinant protein was purified by Ni2+-NTA affinity chromatography.The rabbit serum was harvested after immunization with recombinant FtsZ protein,and was analyzed by indirect ELISA and Western blotting.The GTPase activity of FtsZ was measured with the malachite green method.Results showed that successfully constructed recombinant plasmid pET28a-ftsz and the recombinant protein with high purity was obtained;Western blot result indicated that FtsZ could react with the His-tag antibody and the rabbit serum;the polyclonal antibody titer of the rabbit serum reached 1 ∶ 13 107 200;FtsZ have GTPase activity.We successfully prepared S.suis 2 recombinant protein FtsZ having GTPase activity and high titer antiserum would be useful for the further study of S.suis 2 cell division mechanism.

Objective To explore factors influencing the prognosis of hepatocellular carcinoma (HCC) patients after hepatectomy. Methods From May 1994 to January 1998, 189 patients who underwent hepatectomy for HCC were enrolled for reviewing their clinical characteristics, treatment and prognosis. Twenty-two parameters contributing to long-term survival rate (SR) and disease-free SR were analysed. Results The 3,5-year cumulative SR of the whole group was 63%,45%, respectively. The 3,5-year SR and disease-free SR in the curative resection (CR) group ( n =162) were 67%,47% and 45%,26% respectively. Results showed that the way by which a tumor was found, tumor size, portal tumor thrombi, satellite nodule, TNM stage, cirrhosis type, recurrent and treatment, blood transfusion, differentiation grade,and CR were risk factors by individual variable analysis( P =0.0000～0.0034); A multivariable analysis showed that CR, tumor size, tumor finding mode and reoperation were significant factors associating with prognosis( P =0.0000～0.0024). Blood transfusion and type of cirrhosis were closely correlated with tumor-free survival ( P =0.0001). Conclusions Curative resection, tumor size, reoperation for recurrence were important factors for recurrence by multivariate analysis. The severity of concomittant liver cirrhosis and perioperative blood transfusion were closely correlated with postoperative tumor free survival.

Bladder cancer is one of the most common malignant tumors of the urinary system, among which urothelial carcinoma is the main one. The traditional treatment methods are mainly surgical resection and chemotherapy, but the treatment effect of advanced patients is not good, and the prognosis is poor. In recent years, with the development of immune checkpoint inhibitors, there are many treatment options that are more effective than traditional therapies. Programmed cell death protein 1 (PD-1)and programmed cell death ligand 1(PD-L1)inhibitors stop the negative regulation of the immune system by blocking the binding of PD-1 and PD-L1, thereby enhancing the anti-tumor activity of the body's immune system. This article mainly reviews the efficacy and safety of PD-1/PD-L1 inhibitors commonly used in the clinical treatment of locally advanced or metastatic urinary tract carcinoma of the bladder.

Objective:To investigate the safety and feasibility of endoscopic level V lymph node dissection for thyroid cancer.Methods:Two cases undergoing level V lymph node dissection via breast combined with oral approach for papillary thyroid cancer in May. 2021 and Sep.2021 were retrospectively analyzed. The primary thyroid lesions and metastatic lymph nodes were diagnosed pathologically by fine needle aspiration before operation. The routine examination such as ultrasound, CT and laryngoscopy were completed before operation.Results:Both operations were successfully completed under endoscopy. In case 1, one lymph node was found in neck V region, and no metastatic lymph node was found. In case 2, 7 lymph nodes were found in cervical V region. No "shoulder syndrome" encompassing shoulder dysfunction and pain was found in either case.Conclusions:The study on the two cases reveals that level V dissection after the routine operation of endoscopic central and lateral neck dissection via breast combined with oral approach for papillary thyroid cancer is feasible and safe. More cases in further study were needed for to verify the finding.

Emerging SARS-CoV-2 variants have made COVID-19 convalescents susceptible to re-infection and have raised concern about the efficacy of inactivated vaccination in neutralization against emerging variants and antigen-specific B cell response. To this end, a study on a long-term cohort of 208 participants who have recovered from COVID-19 was conducted, and the participants were followed up at 3.3 (Visit 1), 9.2 (Visit 2), and 18.5 (Visit 3) months after SARS-CoV-2 infection. They were classified into three groups (no-vaccination (n = 54), one-dose (n = 62), and two-dose (n = 92) groups) on the basis of the administration of inactivated vaccination. The neutralizing antibody (NAb) titers against the wild-type virus continued to decrease in the no-vaccination group, but they rose significantly in the one-dose and two-dose groups, with the highest NAb titers being observed in the two-dose group at Visit 3. The NAb titers against the Delta variant for the no-vaccination, one-dose, and two-dose groups decreased by 3.3, 1.9, and 2.3 folds relative to the wild-type virus, respectively, and those against the Omicron variant decreased by 7.0, 4.0, and 3.8 folds, respectively. Similarly, the responses of SARS-CoV-2 RBD-specific B cells and memory B cells were boosted by the second vaccine dose. Results showed that the convalescents benefited from the administration of the inactivated vaccine (one or two doses), which enhanced neutralization against highly mutated SARS-CoV-2 variants and memory B cell responses. Two doses of inactivated vaccine among COVID-19 convalescents are therefore recommended for the prevention of the COVID-19 pandemic, and vaccination guidelines and policies need to be updated.

Objective To develop a novel transcatheter tricuspid valve replacement device and test its performance. Methods The transcatheter tricuspid valve stent consisted of double-layer self-expanding nitinol stent, biotissue-derived bovine pericardial leaflets, and PTFE woven. The delivery system, mainly consisting of a handle control unit and a delivery sheath, was sent to the correct position via right atrium or jugular vein. The sheath had a visualization feature, and the handle control unit could realize the functions of stable release and partial recovery of the interventional valve. In addition, this study performed animal survival experiments on the basis of in vitro experiments. A large-white pig was used as the experimental animal. Cardiopulmonary bypass was established through median thoracotomy, then the right atrium was opened, and the interventional valve was released under direct vision without cardiac arrest. Approximately 1 month after interventional valve implantation, the maneuverability and stability of the interventional tricuspid device were evaluated by autopsy. Results Through the animal experiment, the interventional valve was successfully released, and the anchoring was satisfactory. Postoperative transthoracic echocardiography showed that the interventional valve opened and closed well, the flow rate of tricuspid valve was 0.6 m/s, and there was no obvious tricuspid regurgitation. One month after the operation, we dissected the large-white pig and found the interventional valve was not deformed or displaced, the leaflets were well aligned, and there was thrombus attachment in the groove between the inner and outer layers of the interventional valve. Conclusion Animal experiment shows that the novel device can stably and firmly attach to the tricuspid annulus, with good anchoring effect, and effectively reduce paravalvular leakage.