ObjectiveTo investigate the effect of nicotinamide adenine dinucleotide on vascular endothelial injury in hypertension and its molecular mechanism. MethodsC57BL/6J mice were randomly divided into saline group （Saline） and hypertension group （Ang Ⅱ， which were infused with Ang Ⅱ via subcutaneously implanted osmotic pumps）， and supplemented daily with nicotinamide mononucleotide （300 mg/kg）， a precursor of NAD⁺. Blood pressure， endothelial relaxation function and pulse wave velocity were measured after 4 weeks. Wound healing assay and adhesion assay were used to evaluate the function of endothelial cells in vitro. mtROS levels were detected by immunofluorescence staining. RT-PCR was used to detect the mRNA expression of mtDNA， SIRT3 and isocitrate dehydrogenase 2 （IDH2）. 8-hydroxy-2'-deoxyguanosine levels were detected by enzyme-linked immunosorbent assay. The protein expression levels of p-eNOS， eNOS， SIRT3 and IDH2 were detected by Western blot. ResultsNMN supplementation reduced blood pressure （P<0.001） and improved endothelial function and arterial stiffness （P<0.001） in hypertensive mice. In vitro， NMN improved endothelial function in AngII-stimulated endothelial cells （P<0.05） and attenuated mitochondrial oxidative stress levels （P<0.001）. Mechanistically， NMN elevated SIRT3 activity （P<0.001）， which subsequently enhanced IDH activity （P<0.001） and reduced oxidative stress levels in endothelial cells. Conversely， knockdown of IDH2 would reverse the effect of SIRT3 in improving endothelial function （P<0.001）. ConclusionNAD⁺ lowers blood pressure and enhances vascular function in hypertension by reducing the level of oxidative stress in endothelial cells through activation of the SIRT3/IDH2 signal pathway.

Objective: To explore the effects of Cldn14 gene knockout on renal metabolism and stone formation in rats，so as to provide reference for research in the field of urinary calium metabolism and stone formation. Methods: Cldn14 gene knockout homozygous rats and wild-type rats of the same age were randomly divided into 4 groups：wild-type control (WC) group，wild-type ethylene glycol (WE) group，gene knockout control (KC) group and gene knockout ethylene glycol (KE) group，with 10 rats in each group.The WE and KE groups were induced with ethylene glycol + ammonium chloride to form kidney stones，while the WC and KC groups received normal saline gavage.After 4 weeks of standard maintenance feeding，the urine samples were collected to detect the venous blood.The kidneys were collected for HE，Pizzolatto's staining and transmission electron microscopy.The protein in renal tissues was extracted to detect the expressions of Claudin16 and Claudin19. Results: Crystal deposition was observed in the renal tubular lumen of the WE and the KE groups，and more crystals were detected in the KE group.The WE group had a large number of intracytoplasmic black crystalline inclusions observed in renal tubular epithelial cells under transmission electron microscope，followed by the KE and KC groups.Compared with WC and WE groups，KC and KE groups had significantly decreased serum calcium and magnesium levels but significantly increased urinary calcium level.In addition，the urinary calcium level was higher in the WE group than in the WC group and higher in the KE group than in the KC group.The KE group had lower level of Claudin16，but there was no significant difference in the level of Claudin19 among the 4 groups(P>0.05). Conclusion: Knockout of Cldn14 gene alone cannot effectively reduce urinary calcium excretion or reduce the risk of stone formation in rats，which may be related to the decrease of Claudin16 level.

Pyroptosis is the programmed death of cells accompanied by an inflammatory response and is widely involved in the development of a variety of diseases, such as infectious diseases, cardiovascular diseases, and neurodegeneration. It has been shown that cellular scorching is involved in the pathogenesis of pulmonary arterial hypertension ( PAH) in cardiovascular diseases. Patients with PAH have perivascular inflammatory infiltrates in lungs, pulmonary vasculopathy exists in an extremely inflam-matory microenvironment, and pro-inflammatory factors in cellular scorching drive pulmonary vascular remodelling in PAH patients. This article reviews the role of cellular scorch in the pathogenesis of PAH and the related research on drugs for the treatment of PAH, with the aim of providing new ideas for clinical treatment of PAH.

Objective To explore the efficacy and safety of ticagrelor de-escalation and nicorandil therapy in elderly patients with acute coronary syndrome(ACS)after percutaneous coronary intervention(PCI).Methods A total of 300 elderly patients with ACS were selected from the Sixth and Seventh Medical Center of Chinese PLA General Hospital and Beijing Chaoyang Integrative Medicine Emergency Rescue and First Aid Hospital from November 2016 to June 2019,including 153 males and 147 females,aged>65 years old.All the patients received PCI,and all had double antiplatelet therapy(DAPT)scores≥2 and a new DAPT(PRECISE-DAPT)score of≥25.All patients were divided into two groups by random number table method before operation:ticagrelor group(n=146,ticagrelor 180 mg load dose followed by PCI,and ticagrelor 90 mg bid after surgery)and ticagrelor de-escalation + nicorandil group(n=154,ticagrelor 180 mg load dose followed by PCI,ticagrelor 90 mg bid+nicorandil 5 mg tid after surgery,changed to ticagrelor 60 mg bid+ nicorandil 5 mg tid 6 months later).Follow-up was 12 months.The composite end points of cardiovascular death,myocardial infarction and stroke,the composite end points of mild hemorrhage,minor hemorrhage,other major hemorrhage and major fatal/life-threatening hemorrhage as defined by the PLATO study,and the composite end points of cardiovascular death,myocardial infarction,stroke and bleeding within 12 months in the two groups were observed.Results The comparison of general baseline data between the two groups showed no statistically significant difference(P>0.05).There was also no significant difference in the composite end points of cardiovascular death,myocardial infarction and stroke between the two groups(P>0.05).The cumulative incidence of bleeding events in ticagrelor de-escalation + nicorandil group was significantly lower than that in ticagrelor group(P<0.05),while the composite end points of cardiovascular death,myocardial infarction,stroke and bleeding were also significantly lower than those in tecagrelor group(P<0.05).Conclusion In elderly patients with ACS,the treatment of ticagrelor de-escalation + nicorandil after PCI may not increase the incidence of ischemic events such as cardiovascular death,myocardial infarction or stroke,and it may reduce the incidence of hemorrhagic events.

Helicobacter pylori(HP)infection is a Class Ⅰ carcinogen in gastric cancer,closely related to the occurrence of gastric cancer.Many studies have shown that HP eradication has a preventive effect on gastric cancer.However,2.7%-6.1%of patients with early gastric cancer who have been eradicated after endoscopic submucosal dissection(ESD)can still develop metachronous gastric cancer(MGC),and the mechanism of its occurrence is still unclear.In this review,the atrophy of gastric mucosa and intestinal metaplasia cannot be completely reversed after HP eradication,the excessive proliferation of gastric mucosa epithelial cells,the accumulation of genetic abnormalities,the homeostasis imbalance of the epigenetic group,changes in immune microenvironment,the abnormality of stem cells in gastric mucosa,chromatin accessibility,and changes in chromosome remodeling were discussed in the mechanism of carcinogenesis caused by the above molecular changes after ESD and HP eradication in early gastric cancer.

Objective Optimizing the preparation method to improve the quality of mouse lung cryosections to help enhance the specificity of immunofluorescence staining and obtain more accurate and reliable experimental result.Methods C57BL/6 mouse lung tissue was used to make cryosections via the traditional post-freezing fixation method,pre-freezing fixation method,and a modified perfusion pre-freezing fixation method.A laser-scanning confocal microscope was used to observe lung tissue immunofluorescence staining.Whole areas of mouse lung slices were scanned by fluorescence microscope,and the numbers of intact airways per unit area of lung tissue were calculated.Results In the lung cryosections made via the traditional post-freezing fixation method,the alveoli structure was damaged,the airway wall was seriously disrupted,and there was non-specific staining.Lung cryosections made via the pre-freezing fixation method showed relatively intact alveolar and airway structures but collapsed alveoli and several destroyed airways.In the lung cryosections obtained via the modified perfusion pre-freezing fixation method,the structure and morphology of the alveoli and airways were intact and clear.Additionally,the locations of multiple proteins targeted with immunofluorescence staining were accurate.The number of intact airways(diameter ≥100 μm)per unit area in the lung cryosections obtained via the modified perfusion pre-freezing fixation method was higher than that from cryosections made using the pre-freezing fixation method((0.66±0.15)/mm2 vs(0.33±0.14)/mm2,P＜0.05)and was also significantly higher than that from sections made using the traditional post-freezing fixation method((0.66±0.15)/mm2 vs(0.02±0.04)/mm2,P＜0.01).Conclusions The modified perfusion pre-freezing fixation method for cryosections is conducive to maintaining the integrity of mouse lung tissue morphology and obtaining high-quality multiplex immunofluorescence staining result.

Objective:To investigate the clinical efficacy of femoral component revision surgery in addressing polyethylene sleeve wear in rotating hinge knee joints.Methods:A retrospective analysis was conducted on 21 patients who underwent treatment for polyethylene sleeve wear in rotating hinge knee joints at the Department of Orthopaedics, the Fourth Medical Center, PLA General Hospital, spanning from August 2008 to April 2023. There were 8 males and 13 females with a median age of 63(38, 76) years. Among them, 11 cases involved the left side, and 10 cases involved the right side. The average body mass index (BMI) was 25.0(22.5, 31.0) kg/m 2, and all cases underwent unilateral knee joint revision. The time interval from receiving the hinge knee joint prosthesis to revision was 10.5(6.0, 17.0) years, with 18 cases undergoing primary revision and 3 cases undergoing revision for the second time. Revision surgery of the femoral component sleeve was performed in all patients due to polyethylene sleeve wear. Visual analogue scale (VAS), range of motion (ROM) of the knee joint, changes in hip-knee-ankle angle (HKA), and Knee Society score (KSS) were collected and recorded to assess the surgical outcomes. Results:All patients were followed up for a median duration of 12.5(11.7, 13.4) months. Preoperatively, the VAS score was 5(3, 7) points, which significantly decreased to 0(0, 1) points at the last follow-up ( Z=5.721, P<0.001). At the last follow-up, the KSS scores decreased from 41.19±13.65 points preoperatively to 79.81±7.80 points, indicating a statistically significant difference ( t=12.560, P<0.001). HKA increased from 174.65°±5.20° preoperatively to 178.71°±2.79°, with a statistically significant difference ( t=5.533, P<0.001). Knee joint ROM increased from 69.05°±34.37° preoperatively to 110.00°±10.12°, also demonstrating a significant improvement ( t=5.960, P<0.001). Notably, patients exhibited knee joint stability with no passive flexion or extension laxity. Conclusion:Femoral component sleeve revision surgery effectively addresses polyethylene sleeve wear in rotating hinge knee joint prostheses, thereby mitigating the substantial loss of bone and soft tissue associated with overall revision procedures. The early postoperative clinical outcomes are promising and indicative of the efficacy of this surgical intervention.