BACKGROUND:With the development of computer-aided design and computer-aided manufacturing technology,zirconia abutments with a titanium base are widely used in clinic due to its good application advantages,but there are still some problems and a lack of consensus design standards. OBJECTIVE:To review the fabrication methods of Ti-base zirconia abutment,and the effect of abutment connection,emergence design,abutment angle,and bonding on mechanical properties of Ti-base zirconia abutment. METHODS:Relevant literature published from 2010 to 2023 was searched in CNKI and PubMed databases with the search terms"zirconia abutment,titanium base"in Chinese and English,respectively.The search time limit was extended for some classical literature.The relevant literature was obtained through inclusion and exclusion criteria,and 57 eligible documents were included for review. RESULTS AND CONCLUSION:It is recommended that clinicians try to select antirotational titanium bases or rotational titanium bases with a Morse taper connection.Implants should be placed in the correct axial angulation of not more than 15° or with an inclination to the palatal side when using angled zirconia abutments.When a≥30° labial inclination is followed for implant placement,the bite force must be decreased effectively to reduce the risk of mechanical and biological complications of implants,abutments,and prostheses.Ti-base zirconia abutments with a higher gingival height should be selected,and its restorative angle should not exceed 40°.Multilink Hybrid Abutment could be the first choice for extraoral bonding of zirconia abutment to titanium bases.

The pathogenesis of neurodegenerative diseases (NDDs) is fundamentally linked to complex and profound alterations in metabolic networks within the brain, which exhibit marked spatial heterogeneity. While conventional bulk metabolomics is powerful for detecting global metabolic shifts, it inherently lacks spatial resolution. This methodological limitation hampers the ability to interrogate critical metabolic dysregulation within discrete anatomical brain regions and specific cellular microenvironments, thereby constraining a deeper understanding of the core pathological mechanisms that initiate and drive NDDs. To address this critical gap, spatial metabolomics, with mass spectrometry imaging (MSI) at its core, has emerged as a transformative approach. It uniquely overcomes the limitations of bulk methods by enabling high-resolution, simultaneous detection and precise localization of hundreds to thousands of endogenous molecules—including primary metabolites, complex lipids, neurotransmitters, neuropeptides, and essential metal ions—directly in situ from tissue sections. This powerful capability offers an unprecedented spatial perspective for investigating the intricate and heterogeneous chemical landscape of NDD pathology, opening new avenues for discovery. Accordingly, this review provides a comprehensive overview of the field, beginning with a discussion of the technical features, optimal application scenarios, and current limitations of major MSI platforms. These include the widely adopted matrix-assisted laser desorption/ionization (MALDI)-MSI, the ultra-high-resolution technique of secondary ion mass spectrometry (SIMS)-MSI, and the ambient ionization method of desorption electrospray ionization (DESI)-MSI, along with other emerging technologies. We then highlight the pivotal applications of spatial metabolomics in NDD research, particularly its role in elucidating the profound chemical heterogeneity within distinct pathological microenvironments. These applications include mapping unique molecular signatures around amyloid β‑protein (Aβ) plaques, uncovering the metabolic consequences of neurofibrillary tangles composed of hyperphosphorylated tau protein, and characterizing the lipid and metabolite composition of Lewy bodies. Moreover, we examine how spatial metabolomics contributes to constructing detailed metabolic vulnerability maps across the brain, shedding light on the biochemical factors that render certain neuronal populations and anatomical regions selectively susceptible to degeneration while others remain resilient. Looking beyond current applications, we explore the immense potential of integrating spatial metabolomics with other advanced research methodologies. This includes its combination with three-dimensional brain organoid models to recapitulate disease-relevant metabolic processes, its linkage with multi-organ axis studies to investigate how systemic metabolic health influences neurodegeneration, and its convergence with single-cell and subcellular analyses to achieve unprecedented molecular resolution. In conclusion, this review not only summarizes the current state and critical role of spatial metabolomics in NDD research but also offers a forward-looking perspective on its transformative potential. We envision its continued impact in advancing our fundamental understanding of NDDs and accelerating translation into clinical practice—from the discovery of novel biomarkers for early diagnosis to the development of high-throughput drug screening platforms and the realization of precision medicine for individuals affected by these devastating disorders.

BACKGROUND:With the increasing demand for edentulous jaw restoration,"All-on-4"concept is widely used.The load transfer mode of implant is different from that of natural tooth.The three-dimensional finite element analysis can study the stress distribution of implants and surrounding bone tissues under functional loading.On this basis,it provides research methods for finding suitable implant materials,optimizing implant geometry,and designing clinical surgical protocols. OBJECTIVE:To review researches related to three-dimensional finite element analysis in"All-on-4"concept. METHODS:Relevant literature published from 2003 to 2023 was searched in CNKI and PubMed databases with the search terms of"finite element method;All-on-4;edentulous;biomechanics"in Chinese and English.Finally,65 articles were included for review. RESULTS AND CONCLUSION:(1)In the case of insufficient horizontal bone mass,we can choose to apply narrow diameter implants,but we need to pay attention to the effect of the presence of the cantilever on the stress distribution and reduce the risk of failure.(2)The"All-on-4"concept reduces the stress distribution of bone by tilting the distal middle implant,but the ideal angle of the distal implant tilt in different jaw types requires further study.(3)The presence of cantilevers increases the risk of implant failure,and keeping the cantilever length/AP distance ratio at 0.9 helps to minimize mechanical complications.(4)When a framework is made of a material with a lower elastic modulus,the stress on the framework itself will be smaller,but it will increase the stress on the implant,prosthetic screw,abutment and peri-implant bone.On the contrary,when a material with a higher elastic modulus is used,it can reduce the stress on the prosthetic components,implants and peri-implant bone in the restoration,but the stress on the framework itself is higher.(5)The"All-on-4"concept allows for a better mechanistic balance,but requires the development of a long-term,effective treatment program that is tailored to the patient's specific situation.(6)Proper occlusal scheme is the key to the success of implant treatment,and there is no difference between canine-guide occlusion and group function occlusion in terms of the longevity of the restoration.However,there are many factors that influence occlusal design,and further in vitro experiments as well as a number of clinical studies are needed to explore the ideal occlusal design of the"All-on-4".

Objective To construct a set of graduation internship curriculum system suitable for undergraduate students majoring in biomedical engineering to facilitate standardizing the curriculum system of biomedical engineering major.Methods An initial version of the curriculum system was established with the way of letter and the methods of questionnaire survey,Delphi,expert interview and expert brainstorming;then the initial version was adjusted and refined using 2 rounds of expert consultation to form a set of curriculum system for graduation internship for undergraduate students majoring in biomedical engineering,and the curriculum system was validated.Results The curriculum system included 5 first-level catalogs,11 second-level catalogs and 39 third-level catalogs;the 36 third-level catalogs had a curriculum compliance rate of 0.85 to 0.97.Conclusion The curriculum system constructed can be used for graduation internship of biomedical engineering undergraduates,and references are provided for developing standardized and generally applicable graduation internship curriculum system for biomedical engineering undergraduates.[Chinese Medical Equipment Journal,2024,45(9):89-94]

Objective To analyze the genetic subtypes of human immunodeficiency virus (HIV) and the prevalence of pretreatment drug resistance in the newly reported HIV-infected men in Guangxi. Methods The stratified random sampling method was employed to select the newly reported HIV-infected men aged≥50 years old in 14 cities of Guangxi from January to June in 2020.The pol gene of HIV-1 was amplified by nested reverse transcription polymerase chain reaction and then sequenced.The mutation sites associated with drug resistance and the degree of drug resistance were then analyzed. Results A total of 615 HIV-infected men were included in the study.The genetic subtypes of CRF01_AE,CRF07_BC,and CRF08_BC accounted for 57.4% (353/615),17.1% (105/615),and 22.4% (138/615),respectively.The mutations associated with the resistance to nucleoside reverse transcriptase inhibitors (NRTI),non-nucleoside reverse transcriptase inhibitors (NNRTI),and protease inhibitors occurred in 8 (1.3%),18 (2.9%),and 0 patients,respectively.M184V (0.7%) and K103N (1.8%) were the mutations with the highest occurrence rates for the resistance to NRTIs and NNRTIs,respectively.Twenty-two (3.6%) patients were resistant to at least one type of inhibitors.Specifically,4 (0.7%),14 (2.3%),4 (0.7%),and 0 patients were resistant to NRTIs,NNRTIs,both NRTIs and NNRTIs,and protease inhibitors,respectively.The pretreatment resistance to NNRTIs had much higher frequency than that to NRTIs (2.9% vs.1.3%;χ²=3.929,P=0.047).The prevalence of pretreatment resistance to lamivudine,zidovudine,tenofovir,abacavir,rilpivirine,efavirenz,nevirapine,and lopinavir/ritonavir was 0.8%, 0.3%, 0.7%, 1.0%, 1.3%, 2.8%, 2.9%, and 0, respectively. Conclusions CRF01_AE,CRF07_BC,and CRF08_BC are the three major strains of HIV-infected men≥50 years old newly reported in Guangxi,2020,and the pretreatment drug resistance demonstrates low prevalence.
Male ; Humans ; Middle Aged ; Reverse Transcriptase Inhibitors/therapeutic use* ; HIV Infections/drug therapy* ; Drug Resistance, Viral/genetics* ; China/epidemiology* ; Mutation ; HIV-1/genetics* ; Protease Inhibitors/therapeutic use* ; Genotype

Sclerostin, a protein secreted from osteocytes, negatively regulates the WNT signaling pathway by binding to the LRP5/6 co-receptors and further inhibits bone formation and promotes bone resorption. Sclerostin contributes to musculoskeletal system-related diseases, making it a promising therapeutic target for the treatment of WNT-related bone diseases. Additionally, emerging evidence indicates that sclerostin contributes to the development of cancers, obesity, and diabetes, suggesting that it may be a promising therapeutic target for these diseases. Notably, cardiovascular diseases are related to the protective role of sclerostin. In this review, we summarize three distinct types of inhibitors targeting sclerostin, monoclonal antibodies, aptamers, and small-molecule inhibitors, from which monoclonal antibodies have been developed. As the first-in-class sclerostin inhibitor approved by the U.S. FDA, the monoclonal antibody romosozumab has demonstrated excellent effectiveness in the treatment of postmenopausal osteoporosis; however, it conferred high cardiovascular risk in clinical trials. Furthermore, romosozumab could only be administered by injection, which may cause compliance issues for patients who prefer oral therapy. Considering these above safety and compliance concerns, we therefore present relevant discussion and offer perspectives on the development of next-generation sclerostin inhibitors by following several ways, such as concomitant medication, artificial intelligence-based strategy, druggable modification, and bispecific inhibitors strategy.

Objective To understand the epidemiological characteristics of COVID-19 epidemic in Huangpu District of Shanghai, and to provide scientific evidence for prevention and control of COVID-19. Methods Descriptive statistics were used to study the suspected and confirmed cases of COVID-19 reported from January 21 through March 10, 2020 in Huangpu District, Shanghai. Results A total of 120 suspected cases of COVID-19 were reported, of which 12 were diagnosed and 108 were excluded.The first confirmed case was reported on January 21, and the last case was on February 10; the majority (11/12) of the confirmed cases were reported from January 21 through February 1.The average duration of time from the symptom onset to the first medical visit was 2.6 days, whereas the average duration from the first medical visit to the hospital diagnosis was 2.2 days.There were 15 suspected cases with a confirmed history of residence or tourism in Wuhan, in which 6 were confirmed cases.Moreover, 5 suspected cases had a confirmed history of contact with other confirmed cases, in which 3 were confirmed cases.Thus, exposure in Wuhan and exposure to confirmed cases were the most significant risk factors at this stage of the epidemic. Conclusion The 12 cases identified in Huangpu District of Shanghai are all adults, half of whom had confirmed history of exposure in Wuhan.The first cluster of COVID-19 cases in Shanghai is documented in Huangpu District.Epidemiological investigation reveals that the confirmed cases might be infectious the day before the symptom onset.

BACKGROUND: There is limited evidence of the effects of local anesthesia (LA) on outcomes of non-surgical periodontal treatment (NSPT), in particular among the Chinese. This retrospective cohort study aimed to evaluate the effects of LA on short-term treatment outcomes of NSPT and to determine under what circumstances LA should be prescribed to improve these outcomes. METHODS: Data from periodontal examinations of 3980 patients were used. The data were from 3-month re-evaluation records of an electronic periodontal charting record system in the Department of Periodontology of Peking University School and Hospital of Stomatology from June 2008 to January 2015. Descriptive analyses included changes in probing depth (PD) and the Mazza bleeding index (BI). Two-level (patient and tooth) logistic regression models and three-level (patient, tooth, and site) linear regression models were constructed to analyze the influence of LA on PD for all teeth/sites and teeth/sites with an initial PD ≥ 5 mm. Decreases in PD and BI at sites under LA using the initial PD were also compared. RESULTS: A significantly higher mean decrease in PD after NSPT was found in the LA group than in the no local anesthesia (NLA) group (0.98 vs. 0.54 mm, t = 24.12, P < 0.001). A significantly higher probability of decreases was found in the LA group in BI (percentages of teeth with BI > 1 and BI > 2) for all teeth (16.7% vs. 13.8%, t = 3.75, P < 0.001; 34.7% vs. 28.1%, t = 6.73, P < 0.001) and PD for teeth with PD ≥ 5 mm (32.3% vs. 17.3%, t = 28.48, P < 0.001). The difference in PD between the LA and NLA groups increased as the initial PD increased. The difference between the two groups was 0.12 to 0.22 mm for sites with a baseline PD < 7 mm; however, it increased to 0.41 to 1.37 mm for sites with a baseline PD ≥ 7 mm. CONCLUSIONS LA improved the decrease in PD after NSPT. Root debridement at sites with initial PD ≥ 7 mm should be performed under routine LA.

According to the pathological characteristics of symptomatic chronic thoracic and lumbar osteoporotic vertebral fracture (SCOVF), the different clinical treatment methods are selected, including vertebral augmentation, anterior-posterior fixation and fusion, posterior decompression fixation and fusion, and posterior correction osteotomy. However, there is still a lack of a unified understanding on how to choose appropriate treatment method for SCOVF. In order to reflect the new treatment concept and the evidence-based medicine progress of SCOVF in a timely manner and standardize its treatment, the clinical guideline for surgical treatment of SCOVF is formulated in compliance with the principle of scientificity, practicability and advancement and based on the level of evidence-based medicine.

Objective To evaluate the effect of case-PBL method and case-PBL method combined with SPSS software on the teaching of medical statistics for medical undergraduates. Methods Students from two classes major in experimental medicine from Nantong University Xingling College were selected as Experimental Class 1 ( using case-PBL teaching ) and Experimental Class 2 ( using case-PBL teaching combined with SPSS software). Each class attended lessons for five times. The teachers would send cases for each lesson one week in advance, and students would form into groups to access information, learn and discuss independently. Representatives from groups spoke in class, members would complement and discuss, while teachers offered guidance, review, analysis and summary. We shortened the discussion time in the class, and added instructions on the operation steps of SPSS software for case analysis and how to interpret the analysis result correctly in Experiment Class 2 . The Control Class received traditional teaching . Questionnaires, process assessment and final assessment were used to evaluate teaching effectiveness. SPSS 21.0 software was used to implement variance analysis and chi-square test for comparison between groups. Results The scores of the two experimental classes were higher than those of the control class in the five process assessments ( P<0 . 05 ) . Experimental Class 2 was the best in three section process assessments including those of t-test, the rank sum test and the straight-line correlation (P<0.05). However, there was no difference in the theoretical test scores among the three classes (P=0.670). 94％-100％of the students in the two experimental classes believed that the teaching effects of the case-PBL method and case-PBL method combined with SPSS software were better than the traditional teaching method (P<0.05) in such areas as stimulating interest in learning, improving learning efficiency, etc. Students in Experimental Class 2 were more prone to think these methods improved teaching effect. Conclusion The case-PBL teaching combined with the application of SPSS software will further help students to systematically grasp the statistical knowledge and cultivate statistical practice ability . However , neither methods will improve students' theoretical test scores.