The synthetic PDCoV N protein gene was optimized and cloned into the pET-30a vector to obtain the pET-30a-N plasmid.Thenthe recombinant plasmid was transformed into three strains of BL21 E.coli using heat-shock to explore protein expression conditions.The expressed proteins was purified using Ni Focurose 6FF(IMAC)and used as antigen to immunize the New Zealand White rabbit to prepare the polyclonal antibody against the PDCoV N protein.The antibody titer was measured by indirect ELISA method.The specificity for the antibody was identified by West-ern blot and indirect immunofluorescence(IFA).The results showed that the pET-30a-N plasmid showed high expression level in BL21 StarTM(DE 3).The optimal expression condition was 37 ℃ 4 h.The purity of the target protein could reach 90.3％after purification.Indirect ELISA showed that the antibody titers was up to 1∶204 800.Western blot and IFA showed that the produced rabbit polyclonal antibody exhibited good specificity.In conclusion,the polyclonal antibody was prepared which specifically recognized the PDCoV N proteins.The results provided some references for the subsequent exploration of PDCoV N protein function and laid a foundation for establishing a diag-nostic method for PDCoV.

The synthetic PDCoV N protein gene was optimized and cloned into the pET-30a vector to obtain the pET-30a-N plasmid.Thenthe recombinant plasmid was transformed into three strains of BL21 E.coli using heat-shock to explore protein expression conditions.The expressed proteins was purified using Ni Focurose 6FF(IMAC)and used as antigen to immunize the New Zealand White rabbit to prepare the polyclonal antibody against the PDCoV N protein.The antibody titer was measured by indirect ELISA method.The specificity for the antibody was identified by West-ern blot and indirect immunofluorescence(IFA).The results showed that the pET-30a-N plasmid showed high expression level in BL21 StarTM(DE 3).The optimal expression condition was 37 ℃ 4 h.The purity of the target protein could reach 90.3％after purification.Indirect ELISA showed that the antibody titers was up to 1∶204 800.Western blot and IFA showed that the produced rabbit polyclonal antibody exhibited good specificity.In conclusion,the polyclonal antibody was prepared which specifically recognized the PDCoV N proteins.The results provided some references for the subsequent exploration of PDCoV N protein function and laid a foundation for establishing a diag-nostic method for PDCoV.

This study aims to optimize the process for preparing chitosan-based ultrasound-coupled hydrogel pads and investigate their application potential in ultrasonography. Chitosan, 2-acrylamido-2-methylpropanesulfonic acid, and N-isopropylacrylamide were used as the main materials to prepare chitosan-based ultrasound-coupled hydrogel pads. The free-radical polymerization conditions were optimized by a three-factor, three-level orthogonal test with the tensile strength and ultrasound image quality of the hydrogel pads as evaluation indicators. The optimal prescription was selected by optimizing three factors of raw material ratio, polymerization temperature, and freeze-drying time. The structure and performance of the hydrogel pads were characterized by a scanning electron microscope, a universal testing machine, and an ultrasonic diagnostic instrument. The results showed that the optimal prescription was as follows: the chitosan: 2-acrylamide-2-methylpropanesulfonic acid: N-isopropylacrylamide ratio of 2:0.55:17.27, the polymerization temperature of 25 ℃, and the freeze-drying time of 48 h. The ultrasonically-coupled hydrogel pads prepared under these conditions were transparent, with a porous structure, good adhesion, and high tensile strength. The hydrogel pads had good swelling properties and the swelling degree decreased slowly on day 10. The quality of the ultrasound images obtained via chitosan-based hydrogel pads was not significantly different from that obtained via medical ultrasound coupling agent. In this study, we analyzed the effects of different preparation processes on the gel formation of chitosan-based ultrasound-coupled hydrogel pads. The hydrogel pads were transparent and mild and non-irritating to the human body, serving as an ultrasound transmission material for ultrasonography.
Chitosan/chemistry* ; Hydrogels/chemistry* ; Acrylamides/chemistry* ; Ultrasonography ; Polymerization ; Sulfonic Acids/chemistry* ; Alkanesulfonates/chemistry* ; Tensile Strength ; Freeze Drying ; Temperature

Objective Small cell carcinoma of the bladder(SCCB)is a rare malignant tumor of the bladder.This study aims to explore its clinicopathological features and prognostic factors and to explore the role of perioperative treatment methods.Methods The clinical data of SCCB patients admitted to West China Hospital,Sichuan University over 8 years from January 2016 to January 2024 were collected.The clinicopathological features of SCCB were summarized.The survival outcomes and prognostic factors were analyzed.The effect of perioperative treatment on the improvement in prognosis was explored.Results A total of 31 confirmed cases of SCCB were enrolled.We observed a number of clinicopathologic features.All cases had advanced clinical staging,with the T staging status being above T2 in all cases,and distant metastasis was found in 23％of the newly diagnosed cases.A high proportion of the SCCB cases were combined with other histologic types,with 96％showing combination with urothelial carcinoma(UC).The SCCB patients had a poor prognosis,presenting a median survival of 12 months,1-year overall survival(OS)of 57.9％,and 3-year OS of 27.6％.Patients with extensive-stage SCCB had a significantly worse prognosis than those with limited-stage SCCB did(median OS time of 17.0 months vs.4.4 months,P＜0.05).In limited-stage SCCB,the median OS of patients who underwent radical cystectomy(RC)was 19.9 months,while that of the patients who did not undergo RC was 15.2 months(P＜0.05).The OS of patients who received perioperative therapy in combination with RC had longer OS than those who received only RC did(P＜0.05).Among these,patients recevied neoadjuvant therapy(NAT)had a significantly longer OS than patients who didn't receive NAT(P＜0.05).Subgroup analysis revealed that patients who were responsive to neoadjuvant therapy had longer disease-free survival and longer OS than those who were not responsive did(P＜0.05).Lymph node metastasis was an independent factor of poor prognosis(hazard ratio[HR]=15.21,95％confidence interval[CI]:1.732-133.912,P=0.014).NAT prior to RS was an independent protective factor,significantly reducing the risk of death compared with RC alone(HR=0.03,95％CI:0.001-0.724,P=0.031).Conclusion RC is an effective treatment that prolongs the survival of patients with limited-stage SCCB.RS combined with NAT can further improve their survival.

Objective: To describe the current reporting of pneumonia of unknown etiology (PUE) and factors that affect reporting by clinicians in China using the PUE surveillance system in order to provide a reference for improving PUE reporting rates in the future. Methods: Clinicians were recruited via the Sojump platform and requested to complete an anonymous self-administered questionnaire. Multivariate logistic regression analysis was used to assess factors influencing clinicians' reporting activities. Results: This study showed a low PUE case reporting rate and a poor understanding of PUE reporting among the investigated clinicians. Of the 136 clinicians who had diagnosed PUE cases, multivariate logistic regression analysis results showed that clinicians who had attended in-hospital training were more likely to report PUE than those who had not (OR 4.48, 95% CI 1.49-13.46). Clinicians with an expert panel on PUE in their hospital were more likely to report PUE cases than those without (OR 5.46, 95% CI 1.85-16.11). Conclusions: There is a need to promote and reinforce PUE surveillance system training among medical staff. In addition, PUE testing technologies in hospital laboratories should be upgraded, especially in primary and unclassified hospitals, to increase surveillance efficiency and improve PUE reporting rates.