Aim To study the effect of menthol on hypobaric hypoxia-induced pulmonary arterial hypertension and explore the underlying mechanism in mice. Methods 10 to 12 weeks old wild type (WT) mice and TRPM8 gene knockout (TRPM8

BACKGROUND:Compared with traditional two-dimensional culture,three-dimensional microtissue culture can show greater advantages.However,more favorable cultivation methods in three-dimensional culture still need to be further explored. OBJECTIVE:To evaluate the cell behavior of microtissue and its ability to promote cartilage formation under two three-dimensional culture methods. METHODS:Cartilage-derived microcarriers were prepared by chemical decellularization and tissue crushing.DNA quantification and nuclear staining were used to verify the success of decellularization,and histological staining was used to observe the matrix retention before and after decellularization.The microcarriers were characterized by scanning electron microscopy and CCK-8 assay.Cartilage-derived microtissues were constructed by combining cartilage-derived microcarriers with human adipose mesenchymal stem cells through three-dimensional static culture and three-dimensional dynamic culture methods.The cell viability and chondrogenic ability of the two groups of microtissues were detected by scanning electron microscopy,live and dead staining,and RT-qPCR. RESULTS AND CONCLUSION:(1)Cartilage-derived microcarriers were successfully prepared.Compared with before decellularization,the DNA content significantly decreased after decellularization(P<0.001).Scanning electron microscope observation showed that the surface of the microcarrier was surrounded by collagen,maintaining the characteristics of the natural extracellular matrix of cartilage cells.CCK-8 assay indicated that microcarriers had no cytotoxicity and could promote cell proliferation.(2)Scanning electron microscopy and live and dead staining results showed that compared with the three-dimensional static group,the three-dimensional dynamic group had a more extended morphology of microtissue cells,and extensive connections between cells and cells,between cells and matrix,and between matrix.(3)The results of RT-qPCR showed that the expressions of SOX9,proteoglycan,and type Ⅱ collagen in microtissues of both groups were increased at 7 or 14 days.The relative expression levels of each gene in the three-dimensional dynamic group were significantly higher than those in the three-dimensional static group at 14 days(P<0.05).At 21 days,the three-dimensional static group had significantly higher gene expression compared with the three-diomensional dynamic group(P<0.001).(4)The results showed that compared with three-dimensional static culture microtissue,three-dimensional dynamic culture microtissue could achieve higher expression of chondrogen-related genes in a shorter time,showing better cell viability and chondrogenic ability.

Objective:To study the current status of longitudinal extrauterine growth restriction (EUGR) in extremely preterm infants (EPIs) and to develop a prediction model based on clinical data from multiple NICUs.Methods:From January 2017 to December 2018, EPIs admitted to 32 NICUs in North China were retrospectively studied. Their general conditions, nutritional support, complications during hospitalization and weight changes were reviewed. Weight loss between birth and discharge > 1SD was defined as longitudinal EUGR. The EPIs were assigned into longitudinal EUGR group and non-EUGR group and their nutritional support and weight changes were compared. The EPIs were randomly assigned into the training dataset and the validation dataset with a ratio of 7∶3. Univariate Cox regression analysis and multiple regression analysis were used in the training dataset to select the independent predictive factors. The best-fitting Nomogram model predicting longitudinal EUGR was established based on Akaike Information Criterion. The model was evaluated for discrimination efficacy, calibration and clinical decision curve analysis.Results:A total of 436 EPIs were included in this study, with a mean gestational age of (26.9±0.9) weeks and a birth weight of (989±171) g. The incidence of longitudinal EUGR was 82.3%(359/436). Seven variables (birth weight Z-score, weight loss, weight growth velocity, the proportion of breast milk ≥75% within 3 d before discharge, invasive mechanical ventilation ≥7 d, maternal antenatal corticosteroids use and bronchopulmonary dysplasia) were selected to establish the prediction model. The area under the receiver operating characteristic curve of the training dataset and the validation dataset were 0.870 (95% CI 0.820-0.920) and 0.879 (95% CI 0.815-0.942), suggesting good discrimination efficacy. The calibration curve indicated a good fit of the model ( P>0.05). The decision curve analysis showed positive net benefits at all thresholds. Conclusions:Currently, EPIs have a high incidence of longitudinal EUGR. The prediction model is helpful for early identification and intervention for EPIs with higher risks of longitudinal EUGR. It is necessary to expand the sample size and conduct prospective studies to optimize and validate the prediction model in the future.

Temporomandibular joint (TMJ) diseases are common clinical conditions. The number of patients with TMJ diseases is large, and the etiology, epidemiology, disease spectrum, and treatment of the disease remain controversial and unknown. To understand and master the current situation of the occurrence, development and prevention of TMJ diseases, as well as to identify the patterns in etiology, incidence, drug sensitivity, and prognosis is crucial for alleviating patients′suffering.This will facilitate in-depth medical research, effective disease prevention measures, and the formulation of corresponding health policies. Cohort construction and research has an irreplaceable role in precise disease prevention and significant improvement in diagnosis and treatment levels. Large-scale cohort studies are needed to explore the relationship between potential risk factors and outcomes of TMJ diseases, and to observe disease prognoses through long-term follw-ups. The consensus aims to establish a standard conceptual frame work for a cohort study on patients with TMJ disease while providing ideas for cohort data standards to this condition. TMJ disease cohort data consists of both common data standards applicable to all specific disease cohorts as well as disease-specific data standards. Common data were available for each specific disease cohort. By integrating different cohort research resources, standard problems or study variables can be unified. Long-term follow-up can be performed using consistent definitions and criteria across different projects for better core data collection. It is hoped that this consensus will be facilitate the development cohort studies of TMJ diseases.

AIM To study the amino acids and proteins in 16 batches of commercial fish swim-bladders with different origins.METHODS A high performance liquid chromatography method based on pre-column derivatization using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate(AQC)was developed for the determination of contents and components of 17 amino acids in fish swim-bladders.Sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE)was performed to analyze the molecular weight distribution of proteins from different fish swim-bladders,and proteins in fish swim-bladders were identified by proteomics method.RESULTS The result showed that the determination of 17 amino acids had a good linear relationship(R2≥0.998 0).The average recovery rate was 85.62%-109.60%and the relative standard deviations of precision,stability and repeatability were less than 3.5%.The total content of the 17 amino acids in 16 batches of fish swim-bladders ranged from 468.31 mg/g to 620.05 mg/g.A total of 688 proteins including 11 collagens were identified from 16 batches of fish swim-bladder samples and a plenty of low-abundance proteins at 52-95 kDa were also detected in fish swim-bladders by SDS-PAGE.CONCLUSION This study provides a good reference for the quality evaluation and further utilization of fish swim-bladders.

Objective To understand the respiratory protection competency of staff in hospitals.Methods Staff from six hospitals of different levels and characteristics in Beijing were selected,including doctors,nurses,medical technicians,and servicers,to conduct knowledge assessment on respiratory protection competency.According to exposure risks of respiratory infectious diseases,based on actual cases and daily work scenarios,content of respira-tory protection competency assessment was designed from three aspects:identification of respiratory infectious di-seases,transmission routes and corresponding protection requirements,as well as correct selection and use of masks.The assessment included 6,6,and 8 knowledge points respectively,with 20 knowledge points in total,all of which were choice questions.For multiple-choice questions,full marks,partial marks,and no mark were given respective-ly if all options were correct,partial options were correct and without incorrect options,and partial options were correct but with incorrect options.Difficulty and discrimination analyses on question of each knowledge point was conducted based on classical test theory.Results The respiratory protection competency knowledge assessment for 326 staff members at different risk levels in 6 hospitals showed that concerning the 20 knowledge points,more than 60％participants got full marks for 6 points,while the proportion of full marks for other questions was relatively low.Less than 10％participants got full marks for the following 5 knowledge points:types of airborne diseases,types of droplet-borne diseases,conventional measures for the prevention and control of healthcare-associated infec-tion with respiratory infectious diseases,indications for wearing respirators,and indications for wearing medical protective masks.Among the 20 knowledge questions,5,1,and 14 questions were relatively easy,medium,and difficult,respectively;6,1,4,and 9 questions were with discrimination levels of ≥0.4,0.30-0.39,0.20-0.29,and ≤0.19,respectively.Conclusion There is still much room for hospital staff to improve their respiratory protection competency,especially in the recognition of diseases with different transmission routes and the indications for wearing different types of masks.

Objective To investigate the environmental contamination related to first patient with carbapenem-re-sistant Acinetobacter baumannii(CRAB)infection and the infection status of relevant patients in a newly established intensive care unit(ICU)of a hospital in Tibetan area,and analyze the transmission risk.Methods From the ad-mission in ICU of a patients who was first detected CRAB on November 15,2021 to the 60th day of hospitalization,all patients who stayed in ICU for＞48 hours were performed active screening on CRAB.On the 30th day and 60th day of the admission to the ICU of the first CRAB-infected patient,environment specimens were taken respectively 2 hours after high-frequency diagnostic and therapeutic activities but before disinfection,and after disinfection but before medical activities.CRAB was cultured with chromogenic culture medium.Results Among the 13 patients who were actively screened,1 case was CRAB positive,he was transferred from the ICU of a tertiary hospital to the ICU of this hospital on November 19th.On the 40th day of admission to the ICU,he had fever,increased frequency for sputum suction,and CRAB was detected.The drug sensitivity spectrum was similar to that of the first case,and he also stayed in the adjacent bed of the first case.64 environmental specimens were taken,and 9 were positive for CRAB,with a positive rate of 14.06％,8 sampling points such as the washbasin,door handle and bed rail were positive for CRAB after high-frequency diagnostic and therapeutic activities.After routine disinfection,CRAB was detected from the sink of the washbasin.Conclusion For the prevention and control of CRAB in the basic-level ICU in ethnic areas,it is feasible to conduct risk assessment on admitted patients and adopt bundled prevention and con-trol measures for high-risk patients upon admission.Attention should be paid to the contaminated areas(such as washbasin,door handle,and bed rail)as well as the effectiveness of disinfection of sink of washbasin.

Objective To analyze the atrioventricular synchronization rate after implantation of Micra AV leadless pacemaker,and the impact of postoperative programming optimization on atrioventricular synchronization rate.Methods A prospective cohort study was conducted to select patients with complete atrioventricular block who underwent Micra AV leadless pacemaker implantation at Beijing Anzhen Hospital from August 2022 to June 2023.Programming optimization were performed at 1 week,1 month,and 3 months postoperatively,and atrioventricular synchronization rate,electrical parameters,and echocardiography were recorded.Results A total of 68 patients with complete atrioventricular block implanted with Micra AV were selected,with an average age of(68.2±9.7)years,including 47 males(69.1％).All patients were successfully implanted with Micra AV,and there were no serious postoperative complications;The average threshold,sense,and impedance parameters were stable during 1 week,1 month,and 3 months after the procedure;There was no significant difference in the EF value of postoperative echocardiography(P=0.162);The average atrioventricular synchronization rates at 1 week,1 month,and 3 months postoperatively were(75.2％vs.83.8％vs.91.6％,P=0.001).Conclusions As an mechanical atrial sensing,Micra AV requires personalized adjustment of relevant parameters;Postoperative follow-up programming optimization plays an important role in the atrioventricular synchronization and comfort level in patients with complete atrioventricular block after implantation of Micra AV leadless pacemaker.

Objective:To explore brain network properties and their relationship with cognitive function in children with spastic cerebral palsy (SCP) using diffusion tensor imaging (DTI) based graph theory analysis.Methods:The study was a cross-sectional study. Clinical and imaging data of 21 children with SCP (SCP group) and 32 healthy children (control group) who underwent cranial MRI at the Affiliated Hospital of Zunyi Medical University from August 2020 to April 2022 were analyzed retrospectively. 3D-T 1WI, DTI and Wechsler Intelligence Scale were assessed for all subjects. The Wechsler Intelligence Scale included the verbal comprehension index (VCI), the processing speed index (PSI), the work memory index (WMI), and the perceptual reasoning index (PRI), etc., and ultimately the full scale intelligence quotient (FSIQ) scores were obtained based on the indices of each subscale. Independent samples t-test was used to analyze the differences in the small world attributes [small-world index (σ), normalized shortest path length (λ), normalized clustering coefficients (γ)], global attributes [global efficiency (Eglob), local efficiency (Eloc), characteristic path length (Lp), clustering efficiency (Cp)] and node attributes [degree centrality(DC), nodal efficiency (Ne), betweeness centrality (Bc), nodal shortest path length (NLp), nodal clustering efficiency, nodal local efficiency] between two groups of children′s brain networks. Brain network indicators with statistically significant differences between the 2 groups were correlated with Wechsler Intelligence Scale scores using Spearman. Results:The FSIQ scores on the Wechsler Intelligence Scale and the VCI, WMI, PSI, and PRI were lower in the SCP group than in the control group, and the differences were all statistically significant (all P<0.05). Both groups of children′s brain networks had small world properties. Compared with the control group, Eglob decreased, Lp and λ increased in the SCP group (all P<0.05). Compared with the control group, DC and Ne in multiple brain regions decreased, NLp increased in the SCP group (all P<0.05, FDR corrected). Correlation analysis showed that DC in the right parsopercularis was positively correlated with FSIQ, VCI, WMI and PRI( r=0.53, 0.47, 0.47, 0.60, P=0.019, 0.045, 0.044, 0.020, respectively); NLp in the right parsopercularis was negatively correlated with PRI( r=-0.56, P=0.030); Ne in left paracentral, the right parsopercularis, right precentral, right postcentra were positively correlated with PRI( r=0.62, 0.56, 0.53, 0.54, P=0.015, 0.031, 0.044, 0.039, respectively); Ne in the right precentral was positively correlated with WMI ( r=0.48, P=0.039) in the SCP group. Conclusions:There are changes in the topological attributes of global and multiple regional brain networks in SCP. The changes in the attributes of nodes in the right parsopercularis, right precentral, right postcentral, and left paracentral could reflect cognitive dysfunction in children with SCP.

Background::Very low birth weight (VLBW) infants are the key populations in neonatology, wherein morbidity and mortality remain major challenges. The study aimed to analyze the clinical characteristics of VLBW infants.Methods::A retrospective cohort study was conducted in West China Second Hospital between January 2016 and December 2021. Neonates with a birth weight of <1500 g were included. Mortality, care practices, and major morbidities were analyzed, and compared with those of previous 7 years (2009-2015).Results::Of the total 1750 VLBW, 1386 were infants born with birth weight between 1000-1499 g and 364 infants were born with weight below 1000 g; 42.9% (751/1750) required delivery room resuscitation; 53.9% (943/1750) received non-invasive ventilation only; 38.2% (669/1750) received invasive ventilation; 1517 VLBW infants received complete treatment. Among them, 60.1% (912/1517) of neonates had neonatal respiratory distress syndrome (NRDS), 28.7% (436/1517) had bronchopulmonary dysplasia (BPD), 22.0% (334/1517) had apnea, 11.1% (169/1517) had culture-confirmed sepsis, 8.4% (128/1517) had pulmonary hemorrhage, 7.6% (116/1517) had severe intraventricular hemorrhage (IVH)/periventricular leukomalacia (PVL), 5.7% (87/1517) had necrotizing enterocolitis (NEC), and 2.0% (31/1517) had severe retinopathy of prematurity. The total and in-hospital mortality rates were 9.7% (169/1750) and 3.0% (45/1517), respectively. The top three diagnoses of death among those who had received complete treatment were sepsis, NRDS, and NEC. In 2009-2015, 1146 VLBW were enrolled and 895 infants received complete treatment. The proportions of apnea, IVH, and IVH stage ≥3/PVL, were higher in 2009-2015 compared with those in 2016-2021, while the proportions of NRDS and BPD were characterized by significant increases in 2016-2021. The total and in-hospital mortality rates were 16.7% (191/1146) and 5.6% (50/895) respectively in 2009-2015.Conclusion::Among VLBW infants born in 2016-2021, the total and in-hospital mortality rates were lower than those of neonates born in 2009-2015. Incidences of NRDS and BPD increased in 2016-2021, which affected the survival rates and long-term prognosis of VLBW.