The innate immune sensor NLRP3 inflammasome overactivation is involved in the pathogenesis of ulcerative colitis. PGAM5 is a mitochondrial phosphatase involved in NLRP3 inflammasome activation in macrophages. However, the role of PGAM5 in ulcerative colitis and the mechanisms underlying PGAM5 regulating NLRP3 activity remain unknown. Here, we show that PGAM5 deficiency ameliorates dextran sodium sulfate (DSS)-induced colitis in mice via suppressing NLRP3 inflammasome activation. By combining APEX2-based proximity labeling focused on PGAM5 with quantitative proteomics, we identify NEK7 as the new binding partner of PGAM5 to promote NLRP3 inflammasome assembly and activation in a PGAM5 phosphatase activity-independent manner upon inflammasome induction. Interfering with PGAM5-NEK7 interaction by punicalagin inhibits the activation of the NLRP3 inflammasome in macrophages and ameliorates DSS-induced colitis in mice. Altogether, our data demonstrate the PGAM5-NEK7 interaction in macrophages for NLRP3 inflammasome activation and further provide a promising therapeutic strategy for ulcerative colitis by blocking the PGAM5-NEK7 interaction.

Objective To establish a highly sensitive and specific method for detecting human DNA based on real time quantitative PCR(qPCR)technique for the rapid detection of potential DNA con-tamination sources in DNA laboratories.Methods Primers and probes were designed with Primer Ex-pressTM software using the reference sequence of human 18S rRNA gene as a template,and the opti-mal prime-probe combination was screened by matrix method.The PCR products of the target se-quence of human 18S rRNA gene were used to construct the plasmid,and a plasmid standard was used to draw the standard curve of the qPCR system.According to the Minimum Information for Pub-lication of Quantitative Real-time PCR Experiments(MIQE)guidelines,the specificity,sensitivity,re-peatability and application effect of the qPCR system were evaluated.Results The sensitivity of the qPCR system established in this study was 5.3×10-5 ng/μL,which showed good specificity for human DNA samples.The correlation coefficient of the qPCR system was-0.999,and amplification efficiency was 100％.Both the intra-batch and inter-batch variation coefficients were less than 2％.Conclusion The established human DNA detection method based on qPCR technique has good specificity,high sen-sitivity,and robust stability.It can be used for rapid detection of DNA contamination and daily moni-toring of the accumulated human DNA in the laboratory environment.

Objective To summarize the characteristics of the constitution of orthopedic diseases among soldiers in a sea area,so as to provide the reference for the rational allocation of medical resources,the prevention and treatment of orthopedic diseases,and the improvement of naval medical support.Methods Medical records on injuries of the outpatient and emergency departments in a hospital ship from February 2021 to April 2022 were retrospectively analyzed.The number of varying orthopedic diseases was counted,and descriptive statistical analysis was conducted.Results A total of 200 cases were included in the statistical analysis.The top five diseases were chronic low back pain,knee pain,tibial contusion,wrist joint injury,and shoulder joint injury,and they accounted for 82%of the total orthopedic diseases.Conclusion The medical team stationed on hospital ships should be guided by actual medical needs of officers and soldiers on island,enhance the diagnosis and treatment of common orthopedic diseases,formulate scientific and reasonable prevention and treatment strategies.The allocation of medical materials and personnel should be in line with the spectrum of orthopedic diseases as far as possible to reduce non-combat casualty and strengthen the combat effectiveness of the army.

To explore the value of portable oto-endoscopy system in clinical teaching of otolaryngology residents.

Background::In the clinic, practitioners encounter many patients with an abnormal pattern of dense punctate magnetic resonance imaging (MRI) signal in the basal ganglia, a phenomenon known as "cheese sign". This sign is reported as common in cerebrovascular diseases, dementia, and old age. Recently, cheese sign has been speculated to consist of dense perivascular space (PVS). This study aimed to assess the lesion types of cheese sign and analyze the correlation between this sign and vascular disease risk factors.Methods::A total of 812 patients from Peking Union Medical College Hospital (PUMCH) dementia cohort were enrolled. We analyzed the relationship between cheese sign and vascular risk. For assessing cheese sign and defining its degree, the abnormal punctate signals were classified into basal ganglia hyperintensity (BGH), PVS, lacunae/infarctions and microbleeds, and counted separately. Each type of lesion was rated on a four-level scale, and then the sum was calculated; this total was defined as the cheese sign score. Fazekas and Age-Related White Matter Changes (ARWMC) scores were used to evaluate the paraventricular, deep, and subcortical gray/white matter hyperintensities.Results::A total of 118 patients (14.5%) in this dementia cohort were found to have cheese sign. Age (odds ratio [OR]: 1.090, 95% confidence interval [CI]: 1.064-1.120, P <0.001), hypertension (OR: 1.828, 95% CI: 1.123-2.983, P = 0.014), and stroke (OR: 1.901, 95% CI: 1.092-3.259, P = 0.025) were risk factors for cheese sign. There was no significant relationship between diabetes, hyperlipidemia, and cheese sign. The main components of cheese sign were BGH, PVS, and lacunae/infarction. The proportion of PVS increased with cheese sign severity. Conclusions::The risk factors for cheese sign were hypertension, age, and stroke. Cheese sign consists of BGH, PVS, and lacunae/infarction.

BACKGROUND:Our previous experimental results have shown that hyaluronic acid hydrogel can act as a vehicle for bone marrow mesenchymal stem cell delivery to improve the cardiac function of rats with myocardial infarction. OBJECTIVE:To explore the molecular mechanism of bone marrow mesenchymal stem cells and hyaluronic acid hydrogel in promoting damaged heart repair. METHODS:Bone marrow mesenchymal stem cells from male Sprague-Dawley rats were isolated and cultured,and then hyaluronic acid-encapsulated bone marrow mesenchymal stem cells were cultured in vitro in a three-dimensional manner.A model of myocardial infarction was made by ligating the left anterior descending artery of female Sprague-Dawley rats.After 1 week,the model rats were screened by ultrasonic testing and then eligible ones were randomly divided into four groups:PBS group(n=12),hyaluronic acid group(n=12),bone marrow mesenchymal stem cell group(n=15),and hyaluronic acid-encapsulated bone marrow mesenchymal stem cell group(n=15).At 1 week after ligation,the model rats underwent the secondary thoracotomy followed by corresponding injections into the infarcted region and its marginal zone.The expression levels of matrix metalloproteinase-2,vascular endothelial growth factor,thymosin β4 and c-Kit were examined at post-injection day 1,week 1 and week 2 by western blot assay.At post-injection week 2,immunofluorescence staining was used to detect the differentiation of transplanted cells. RESULTS AND CONCLUSION:(1)The expression levels of matrix metalloproteinase-2 and vascular endothelial growth factor protein in the infarct zone in the bone marrow mesenchymal stem cell group were significantly up-regulated at week 1 compared with the other three groups(P<0.05).At week 2,the hyaluronic acid group had a lower expression of matrix metalloproteinase-2 and vascular endothelial growth factor protein than the other three groups(P<0.05).However,the expression of matrix metalloproteinase-2 and vascular endothelial growth factor protein in the hyaluronic acid+bone marrow mesenchymal stem cell group was not significantly different compared with the bone marrow mesenchymal stem cell group.This was primarily attributable to a prolonged paracrine effect via the controlled release of the hyaluronic acid hydrogel.This prolonged paracrine effect offsets the inhibitory effect induced by hyaluronic acid hydrogel at 2 weeks.(2)Compared with the PBS group,thymosin β4 and c-Kit expression levels in the hyaluronic acid group,bone marrow mesenchymal stem cell group and bone marrow mesenchymal stem cell+hyaluronic acid group were significantly increased(P<0.05).(3)No differentiation of transplanted cells into cardiomyocytes or blood vessels was detected 2 weeks after transplantation.(4)It is indicated that transplanted bone marrow mesenchymal stem cells promote myocardial repair through the paracrine effect,and hyaluronic acid hydrogel prolongs the paracrine effect of transplanted bone marrow mesenchymal stem cells.

To explore the value of portable oto-endoscopy system in clinical teaching of otolaryngology residents.

AIM To study the chemical constituents from the stems of Gnetum parvifolium(Warb.)C.Y.Cheng ex Chun and their xanthine oxidase inhibitory activities.METHODS The 95%ethanol extract from the stems of G.parvifolium was isolated and purified by silica gel,MCI and preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The inhibitory activities on xanthine oxidase was determined by ultraviolet spectrophotometry.RESULTS Seventeen compounds were isolated and identified as isorhapontigenin(1),resveratrol(2),4-hydroxybenzaldehyde(3),cycloeucalenol(4),(E)-1-(3',5'-dimethoxyphenyl)-2-(3,4-dimethoxyphenyl)ethene(5),stigmast-4-en-3-one(6),medioresinol(7),chrysin(8),aurantiamide acetate(9),(-)-pinoresinol(10),methyl 4-hydroxybenzoate(11),2-methoxybenzene-1,4-diol(12),gnetumontain C(13),syringaresinol(14),homoeriodictyol(15),vanillin(16),β-sitosterol(17).The IC50 values of compounds 1-3,15-16 were(11.4±0.54),(14.1±1.06),(320.4±0.75),(360.6±0.78),(386.3±0.71)μmol/L,respectively.CONCLUSION Compounds 3-4 are isolated from this plant for the first time.Compounds 5-13 are first isolated from genus Gnetum.Compounds 1-3,15-16 have xanthine oxidase inhibitory activities.

Objective:To analyze the clinical and imaging features of patients with COVID-19-related osmotic demyelination syndrome (ODS).Methods:COVID-19-related ODS cases diagnosed in the Department of Neurology, Peking Union Medical College Hospital from January 2020 to September 2023 were retrospectively reviewed. And their past medical history, possible triggers, clinical manifestations, imaging manifestations, treatment and prognosis were summarized.Results:A total of 5 patients with COVID-19-related ODS were included. Electrolyte disturbances acted as an inducement of ODS in all patients (5/5),4 of whom with hyponatremia. Four of 5 patients first presented with disturbance of consciousness, followed by predominant dystonia. Imaging of all patients (5/5) showed isolated extrapontine myelinolysis (EPM). With the prolongation of the course of disease, such signal intensity could return to normal, and lesions showed atrophic changes in some patients. The patients′ clinical symptoms were partly relieved within a few days to a few months after treatment.Conclusions:COVID-19-related ODS is mostly associated with hyponatremia, and EPM is more common. COVID-19 should be considered as a risk factor for ODS.