Objective: To understand the subjective and objective comfort evaluations of students from different age groups on desks and chairs, so as to provide reference for standardized allocation and use of desks and chairs. Methods: From January to April 2024, a total of 2 446 students were selected from 26 schools in 13 districts (counties/cities) in Shanghai, Tianjin, and Wuxi from Jiangsu Province by using cluster random method, including students in kindergartens, primary schools, junior high schools,senior high schools, colleges and universities. Standardized procedures were used to measure the height and weight of participants, and the matching desks and chairs models were selected according to the height. The subjective comfort of students on matching desks and chairs was investigated, and their objective comfort was evaluated by using a self designed questionnaire. The χ 2 test was used to analyze the differences of subjective perception and objective evaluation in comfort between different types of desks and chairs. Results: About 84.1% of the students subjectively thought that large desks and small chairs were very comfortable or relatively comfortable, followed by large desks and chairs (75.7%), and the proportion of small desks and chairs was the lowest among the three types (46.2%), and the difference was statistically significant ( χ 2=722.46, P <0.01). The reporting rates of primary school, junior high school and senior high school students who subjectively considered large desks and chairs to be very comfortable/relatively comfortable were higher than that of other types of desks and chairs, and the differences were statistically significant ( χ 2=297.49, 252.82, 343.67, P <0.01). However, there was no significant difference in the subjective comfort evaluation of different types of desks and chairs among kindergarten children ( χ 2=3.21, P >0.05), and 66.3% of the students in colleges and universities felt very comfortable/relatively comfortable when they used the matching standard desks and chairs. The objective evaluation results of the comfort for the three types of desks and chairs were consistent with the subjective evaluation, but the proportions of the objective evaluation as very comfortable/relatively comfortable were higher than that of the subjective evaluation ( χ 2=20.76- 813.47, P <0.01). Conclusions Large desks and chairs, as well as large desks with small chairs are perceived comfortable, while small desks and chairs are perceived less comfortable. It is recommended to match the large desks and chairs or large desks and small chairs that are suitable for them according to the "standard", to promote physical and mental health of students.

Objective: To investigate the differences in the comfort of desks and chairs furniture among students with different body types according to the standard, so as to provide a reference for guiding students with overweight and obesity to choose the correct study furniture and revising the standards. Methods: From January to April 2024, 2 443 students from 26 schools in 13 districts (counties/cities) in Shanghai, Tianjin, and Jiangsu Province were selected by the cluster random sampling method to conduct physical examination. The subjective and objective evaluations of the comfort of height matched desks and chairs were investigated. The students were divided into non overweight, overweight, and obesity groups according to relevant criteria, and stratified analysis was performed. The χ 2 test was used to analyze differences in the comfort evaluations of desks and chairs among students with different body types. Results: Among the 2 443 students surveyed, 16.7% and 12.6% were respectively classified as overweight and obese. All students assigned the highest comfort ratings to large desks and small chairs (84.1%), and consistency was observed between students subjective and objective evaluations. The reporting rate of samll desks and chairs of obesity students subjective evaluation was lower (36.8%) than that of overweight and non overweight/obesity students (52.1%, 48.0%) ( χ 2=14.63, P <0.01). The overweight and obese group of primary school students had a worse evaluation of the comfort of large desks and chairs and small desks and chairs than those of the non overweight and obese groups( χ 2=15.78, 7.63, P <0.05). Among high school students, the overweight and obese group had worse evaluation of the comfort of large desks and chairs, as well as large desks and small chairs, than those of the non-overweight and obese groups( χ 2=9.62, 11.77, P <0.05). The objective evaluations revealed low compliance ratings on the posture of the thighs and calves for naturally forming an angle greater than 90° (55.6%), and headroom height under the table (50.3%) with small desks and chairs ( χ 2=94.05, 166.47, P <0.05). Conclusions Compared with non overweight/obese students, students with overweight and obese students report poor comfort evaluations of height matched desks and chairs. Revision of the standard should consider the body types of students, and evaluations of the comfort of desks and chairs furniture by students with overweight and obesity should be improved.

OBJECTIVE To investigate the improvement effect and mechanism of desloratadine citrate disodium in mice with hypersensitivity pneumonitis （HP）. METHODS Sixty mice were randomly divided into blank control group （normal saline）， model group （normal saline）， prednisone group （positive control， 20 mg/kg） and desloratadine citrate disodium low-， medium- and high-dose groups （0.5， 1， 2 mg/kg）， with 10 mice in each group. Except for the blank control group， mice in other groups were intraperitoneally injected with ovalbumin （OVA） and exposed to OVA inhalation to establish the HP model. On day 22 post- modeling， mice in each group were administered the corresponding drugs or normal saline， once a day， for 11 consecutive days. After the last administration， lung function and airway hyperreactivity were assessed. The levels of interleukin-1β （IL-1β）， IL-4 and IL-6 in serum as well as the levels of IL-8， IL-13 and IL-17A in bronchoalveolar lavage fluid were determined. Pathological changes in lung tissue of mice were evaluated using Masson staining. Furthermore， the expressions of fibrosis-related proteins， including transforming growth factor β1 （TGF-β1）， type Ⅲ collagen （Col-Ⅲ） and fibronectin （FN） were determined in lung tissues. RESULTS Compared with the blank control group， the model group showed significant deterioration in lung function （P＜ 0.01）， while airway resistance and serum levels of IL-1β， IL-4， IL-6 and the levels of IL-8， IL-13 and IL-17A in the bronchoalveolar lavage fluid were increased significantly （P＜0.01）. The lung tissues exhibited alveolar collapse， atrophy， and structural disarray， along with the formation of extensive deposits of blue collagen fibers， the percentage of positive staining increased significantly （P＜0.01）. Additionally， the expression levels of TGF-β1， Col-Ⅲ， and FN proteins in the lung tissues were also increased significantly （P＜0.01）. After intervention with desloratadine citrate disodium， the pathological changes in the lung tissues of mice in each dosage group of desloratadine citrate disodium showed varying degrees of improvement， and most of the aforementioned indicator levels were significantly reversed （P＜0.05 or P＜0.01）. CONCLUSIONS Desloratadine citrate disodium can improve the lung function and airway hyperreactivity of HP mice， inhibit the release of inflammatory factors in serum and bronchoalveolar lavage fluid， and reduce the deposition of collagen fibers. Its mechanism of action may be related to anti-inflammatory， immunomodulatory， and antifibrotic effects.

BACKGROUND:There is an internal relationship between hyperhomocysteinemia and vascular calcification.However,the pathogenesis of hyperhomocysteinemia promoting vascular calcification is still unclear. OBJECTIVE:To investigate the role of bone morphogenetic protein-2 in hyperhomocysteinemia-induced vascular calcification. METHODS:Human carotid wax samples were divided into a calcified group(n=29)and a non-calcified group(n=13)according to the presence or absence of calcified plaque.Sixteen ApoE-/-mice were randomly divided into a control group and a hyperhomocysteinemia group,with 8 mice in each group.Bone morphogenetic protein-2 vector was used to transfect rat thoracic artery smooth muscle A7r5 cells,and gradient concentration of homocysteine(50,100,200,and 400 μmol/L)was utilized to treat A7r5 cells.Calcification was detected by alizarin red staining and hematoxylin-eosin staining.The interaction of bone morphogenetic protein 2 with Runt-related transcription factor 2 was detected by immunofluorescence,and the expressions of bone morphogenetic protein 2,Runt-related transcription factor 2,and α-smooth muscle actin were detected by immunohistochemistry and western blot assay. RESULTS AND CONCLUSION:(1)Human carotid artery tissue staining revealed that compared with the non-calcification group,inflammatory cells increased and calcification positive rate increased in the calcification group(P<0.05).Compared with the non-calcification group,the expressions of bone morphogenetic protein-2 and Runt-related transcription factor 2 were up-regulated,and the expression of α-smooth muscle actin was decreased in the calcification group(all P<0.05).(2)The staining of mouse arterial specimens exhibited that,the positive rate of calcified area in the hyperhomocysteinemia group was significantly higher than that in the control group(P<0.05);serum homocysteine level in the hyperhomocysteinemia group was significantly higher than that in the control group(P<0.05).Compared with the control group,the expressions of bone morphogenetic protein-2 and Runt-related transcription factor 2 were up-regulated,and the expression of α-smooth muscle actin was decreased in the hyperhomocysteinemia group(all P<0.05).(3)A7r5 cell culture analysis demonstrated that with the increase of homocysteine concentration gradient,the degree of calcification,the content of bone morphogenetic protein-2 and Runt-related transcription factor 2 protein in A7r5 cells increased(P<0.05),and the content of α-smooth muscle actin protein decreased(P<0.05).(4)The A7r5 cell culture analysis of overexpressed bone morphogenetic protein 2 showed that the calcification degree of the overexpressed bone morphogenetic protein 2 group was increased compared with the corresponding control group,the β-sodium glycerophosphate group,and the homocysteine group.RUNt-related transcription factor 2 expression up-regulated(P<0.05)and α-smooth muscle actin expression down-regulated(P<0.05).(5)The expression of bone morphogenetic protein 2 increased in A7r5 cells cultured with homocysteine in calcified medium,and the expression of Runt-related transcription factor 2 increased with the increase of bone morphogenetic protein 2 expression.(6)The results confirm that bone morphogenetic protein-2 is a key target gene in the regulation of smooth muscle cell phenotypic transformation resulting in vascular calcification by hyperhomocysteinemia.Targeted regulation of bone morphogenetic protein-2 reduces hyperhomocysteinemia-induced vascular calcification.

【Objective】 To explore the distribution of serological markers related to samples whose serological test results were inconsistent with HBV DNA test results among voluntary blood donors in Xi′an. 【Methods】 A total of 71 HBsAg ELISA positive and NAT non-reactive (ELISA+ /NAT-)blood samples were collected from Shaanxi Blood Center from November 1, 2022 to April 30, 2023. The serological markers of hepatitis B were detected by electrochemiluminescence method, and the HBV S region and C region gene fragments were amplified by nested-PCR. 【Results】 The positive rate of nested-PCR in double ELISA+ /NAT- group(n=30) was statistically higher than that of ELISA+ /NAT- group(n=41)(60% vs 24.4%, P<0.05). Donors in double ELISA+ /NAT- group were all first-time blood donors, with the positive rate of anti-HBc in serum of 100%, and the serological pattern was mainly positive for items 1, 4 and 5 items(80%). Among the ELISA+ /NAT- group, 31.7% were repeat blood donors, with the positive rate of anti-HBc in serum of only 19.51%, and the serological patterns were mainly single anti-HBs positive (43.90%) and all negative (36.58%). 【Conclusion】 There are false positives in the test results of ELISA+ /NAT- group, which leads to unnecessary blood discarding. Meanwhile, the samples with negative NAT may have low levels of HBV DNA, which may lead to missed detection. It is suggested that multiple systems and methods should be applied to trace the blood donors who are HBsAg positive and NAT non-reactive, so as to improve the accuracy of HBV screening of blood donors and reduce blood waste.

Objective To evaluate the stability and aesthetic effect of a xenogeneic collagen matrix(mucograft)on achieving an adequate keratinized mucosa width(KMW)around implants and to provide a reference basis for the clini-cal application of xenogeneic collagen matrix materials.Methods The hospital ethics committee approved the study protocol,and the patients provided informed consent.Twenty patients with a KMW＜2 mm at the buccal implant site who were treated in Binzhou Medical University Affiliated Yantai Stomatological Hospital from July 2020 to September 2022 were included,and a total of 36 implants were included.The mean age of the patients was(52.0±10.4)years,of which 18 were females and 2 were males.They were divided into a free gingival graft group(FGG,control group)and a xenogeneic collagen matrix group(test group)according to different graft materials.The incremental effect of the KMW on the buccal side of the implant and the mucosal shrinkage rate was measured at 1 month and 3 months after the opera-tion.The mucosal scar index(MSI)was evaluated after the operation.Results At 3 months postoperatively,the KMW was(3.67±1.06)mm in the control group and(2.96±0.98)mm in the test group,and the difference was statistically significant(t=2.076,P＜0.05).The KMW shrinkage rate was(33.34±16.30)％in the test group and(22.05± 15.47)％in the control group at 1 month postoperatively and(51.95±12.60)％in the test group and(37.44±16.30)％in the control group at 3 months postoperatively,with statistically significant differences between the two groups at the same time points(P＜0.05).Three months after surgery,the test group showed significantly better outcomes than the control group in terms of the five scar indicators(scar width,scar convexity,scar color,scar trace,and overall appear-ance),and the difference was statistically significant(P＜0.05).Conclusion Xenogeneic collagen matrix can increase the peri-implant KMW and achieve a more natural and coordinated soft tissue aesthetic effect but with a higher shrink-age rate.

Digital intraoral scanning is a hot topic in the field of oral digital technology.In recent years,digital intra-oral scanning has gradually become the mainstream technology in orthodontics,prosthodontics,and implant dentistry.The precision of digital intraoral scanning and the accuracy and stitching of data collection are the keys to the success of the impression.However,the operators are less familiar with the intraoral scanning characteristics,imaging process-ing,operator scanning method,oral tissue specificity of the scanned object,and restoration design.Thus far,no unified standard and consensus on digital intraoral scanning technology has been achieved at home or abroad.To deal with the problems encountered in oral scanning and improve the quality of digital scanning,we collected common expert opin-ions and sought to expound the causes of scanning errors and countermeasures by summarizing the existing evidence.We also describe the scanning strategies under different oral impression requirements.The expert consensus is that due to various factors affecting the accuracy of digital intraoral scanning and the reproducibility of scanned images,adopting the correct scanning trajectory can shorten clinical operation time and improve scanning accuracy.The scanning trajec-tories mainly include the E-shaped,segmented,and S-shaped methods.When performing fixed denture restoration,it is recommended to first scan the abutment and adjacent teeth.When performing fixed denture restoration,it is recommend-ed to scan the abutment and adjacent teeth first.Then the cavity in the abutment area is excavated.Lastly,the cavity gap was scanned after completing the abutment preparation.This method not only meets clinical needs but also achieves the most reliable accuracy.When performing full denture restoration in edentulous jaws,setting markers on the mucosal tissue at the bottom of the alveolar ridge,simultaneously capturing images of the vestibular area,using different types of scanning paths such as Z-shaped,S-shaped,buccal-palatal and palatal-buccal pathways,segmented scanning of dental arches,and other strategies can reduce scanning errors and improve image stitching and overlap.For implant restora-tion,when a single crown restoration is supported by implants and a small span upper structure restoration,it is recom-mended to first pre-scan the required dental arch.Then the cavity in the abutment area is excavated.Lastly,scanning the cavity gap after installing the implant scanning rod.When repairing a bone level implant crown,an improved indi-rect scanning method can be used.The scanning process includes three steps:First,the temporary restoration,adjacent teeth,and gingival tissue in the mouth are scanned;second,the entire dental arch is scanned after installing a standard scanning rod on the implant;and third,the temporary restoration outside the mouth is scanned to obtain the three-di-mensional shape of the gingival contour of the implant neck,thereby increasing the stability of soft tissue scanning around the implant and improving scanning restoration.For dental implant fixed bridge repair with missing teeth,the mobility of the mucosa increases the difficulty of scanning,making it difficult for scanners to distinguish scanning rods of the same shape and size,which can easily cause image stacking errors.Higher accuracy of digital implant impres-sions can be achieved by changing the geometric shape of the scanning rods to change the optical curvature radius.The consensus confirms that as the range of scanned dental arches and the number of data concatenations increases,the scanning accuracy decreases accordingly,especially when performing full mouth implant restoration impressions.The difficulty of image stitching processing can easily be increased by the presence of unstable and uneven mucosal mor-phology inside the mouth and the lack of relatively obvious and fixed reference objects,which results in insufficient ac-curacy.When designing restorations of this type,it is advisable to carefully choose digital intraoral scanning methods to obtain model data.It is not recommended to use digital impressions when there are more than five missing teeth.

Objective:To investigate the clinical characteristic and genetic variants of children with carnitine palmitoyltransferase 2(CPT2)deficiency.Methods:The clinical and genetic data of 6 children with CPT2 deficiency were retrospectively analyzed.The blood acylcarnitines and genetic variants were detected with tandem mass spectrometry and whole-exon gene sequencing,respectively.Results:There were 4 males and 2 females with a mean age of 32 months(15 d-9 years)at diagnosis.One case was asymptomatic and with normal laboratory test results,2 had delayed onset,and 3 were of infantile type.Three cases were diagnosed at neonatal screening,and 3 cases presented with clinical manifestations of fever,muscle weakness,and increased muscle enzymes.Five children presented with decreased free carnitine and elevated levels of palmitoyl and octadecenoyl carnitines.CPT2 gene variants were detected at 8 loci in 6 children(4 harboring biallelic mutations and 2 harboring single locus mutations),including 3 known variants(p.R631C,p.T589M,and p.D255G)and 5 newly reported variants(p.F352L,p.R498L,p.F434S,p.A515P,and c.153-2A>G).It was predicted by PolyPhen2 and SIFT software that c.153-2A>G and p.F352L were suspected pathogenic variants,while p.R498L,p.F434S and p.A515P were variants of unknown clinical significance.Conclusions:The clinical phenotypes of CPT2 deficiency are diverse.An early diagnosis can be facilitated by neonatal blood tandem mass spectrometry screening and genetic testing,and most patients have good prognosis after a timely diagnosis and treatment.

Objective:To analyze the mutation of T-cell and B-cell epitopes derived from HBV PreS-S protein in occult hepatitis B virus (OHBV) and investigate the biological mechanisms of occult hepatitis B virus infection (OBI) and HBsAb positive OBI.Methods:The PreS-S region of OBI samples were amplified by nested PCR, the products were sequenced and HBV genotypes were determined. The mutations of T-cell and B-cell epitopes derived from HBV PreS-S protein were analyzed and compared among groups of HBV genotypes and the presence of HBsAb. The affinity of the high frequency of T-cell epitope substitutions were analyzed by SYF PEITHI, the changes of antigenic characteristics of high frequency of B-cell epitope substitutions were analyzed by Ab Designer, Expasy ProtParam tool, Epitope Prediction and Analysis Tools.Results:The PreS-S region of HBV was amplified in 21 samples, including 4 HBsAb+ OBI B, 6 HBsAb-OBI B, 6 HBsAb+ OBI C, 5 HBsAb-OBI C. The mutation rates in PreS-S region of OBI were significantly higher than wild type HBV strains(OBI Bvs. WT B: 2.64%: 0.66%, P<0.001; OBI Cvs. WT C: 3.67%: 1.19%, P<0.001). The mutation rates of the immunoreactive area were significantly higher than non-immunoreactive area in OBI (OBI B: 3.57%: 1.86%, P=0.005; OBI C: 4.78%: 2.65%, P<0.001). The mutation rates of the immunoreactive and non-immunoreactive area in OBI C were higher than OBI B, but there was no statistically significant difference (immunoreactive area: 4.78%: 3.57%, P=0.107; non-immunoreactive area: 2.65%: 1.86%, P=0.142). The mutation rates of T-cell and B-cell epitopes of HBsAb-OBI were higher than HBsAb+ OBI, although there was no significant difference (HBsAb-OBI Bvs. HBsAb+ OBI B: 4.17∶3.01, P=0.303; HBsAb-OBI Cvs. HBsAb+ OBI C: 5.65∶4.26, P=0.207). The affinity analysis of 4 high frequency T-cell epitope substitutions, including T47A/K, S174N, L175S, V177A, showed that the changes of affinity of most mutation sites were not obvious; the antigenicity analysis of 3 high frequency B-cell epitope substitutions, including G73S, K122R, I126M/T, did not show noticeable changes and the hydrophilicity, surface accessibility of some mutation sites were even better than wild strain. Conclusions:The mutation rates in PreS-S region of OBI were significantly higher than wild type HBV strains. The mutation rates of the immunoreactive area were higher than non-immunoreactive area in OBI. The variant activity of OBI C was higher than OBI B. The mutations of OBI might occur randomly and were not selected by antibody pressure. Single epitope and multi-epitopes combinational mutations might be a reason for OBI.

Objective To analyze the research status of job competence in domestic public hospitals,provide directions for the construction of the talent pool in public hospitals,and promote their high-quality development.Methods Relevant litera-ture on job competence in domestic public hospitals from 2009 to 2023 was retrieved from the China National Knowledge Infra-structure(CNKI)database.Citespace software was used to analyze the selected literature in terms of publication timeline,author co-occurrence,institution co-occurrence,keyword co-occurrence,keyword clustering,and keyword burst analysis.A visualized knowledge map was constructed.Results A total of 501 valid articles were included.Research on job competence in domestic public hospitals showed an upward trend from 2009 to 2023.The research hotspots were mainly in the areas of resident physicians and nursing.The burst analysis of keywords indicated that targeted research on job competence in specific professional fields will be a future trend.Conclusion Research on job competence in domestic public hospitals is developing,but it still faces issues such as a loose network structure of author and institution co-occurrence and a lack of cooperation,as well as insufficient subdivi-sion of job competence research in specific professional fields.Therefore,it is necessary to further subdivide professional fields,expand research on job responsibilities,talent cultivation,and performance evaluation in different fields,and encourage collabo-ration among scholars and institutions.Continuous innovation and strategic responses are needed to promote the high-quality de-velopment of public hospitals.