Noncarious lesions,a multifactorial condition encompassing tooth attrition,abrasion,and erosion,have a surge in prevalence and required increased attention in clinical practice.These nonbacterial-associated tooth de-fects can compromise aesthetics,phonetics,and mastica-tory functions.When providing full-arch fixed occlusal rehabilitation for such cases,the treatment strategy should extend beyond by restoring dentition morphology and aesthetics.This report details a complex case of erosive dental wear addressed through a fully digital,full-arch fixed occlusal rehabilitation.A 4D virtual patient was created using multiple digital data sources,including intraoral scanning,3D facial scanning,digital facebow registration,and mandibular movement tracing.With a comprehensive understanding of the masticatory system,various types of microinvasive prostheses were customized for each tooth,including labial ve-neers,buccal-occlusal veneers,occlusal veneers,overlays,inlays,and full crowns,were customized for each tooth.The reported digital workflow offered a predictable diagnostic and treatment strategy,which was facilitated by virtual visual-ization and comprehensive quality control throughout the process.

Background::Exercise, as the cornerstone of pulmonary rehabilitation, is recommended to chronic obstructive pulmonary disease (COPD) patients. The underlying molecular basis and metabolic process were not fully elucidated.Methods::Sprague-Dawley rats were classified into five groups: non-COPD/rest ( n = 8), non-COPD/exercise ( n = 7), COPD/rest ( n = 7), COPD/medium exercise ( n = 10), and COPD/intensive exercise ( n = 10). COPD animals were exposed to cigarette smoke and lipopolysaccharide instillation for 90 days, while the non-COPD control animals were exposed to room air. Non-COPD/exercise and COPD/medium exercise animals were trained on a treadmill at a decline of 5° and a speed of 15 m/min while animals in the COPD/intensive exercise group were trained at a decline of 5° and a speed of 18 m/min. After eight weeks of exercise/rest, we used ultrasonography, immunohistochemistry, transmission electron microscopy, oxidative capacity of mitochondria, airflow-assisted desorption electrospray ionization-mass spectrometry imaging (AFADESI-MSI), and transcriptomics analyses to assess rectal femoris (RF). Results::At the end of 90 days, COPD rats’ weight gain was smaller than control by 59.48 ± 15.33 g ( P = 0.0005). The oxidative muscle fibers proportion was lower ( P < 0.0001). At the end of additional eight weeks of exercise/rest, compared to COPD/rest, COPD/medium exercise group showed advantages in weight gain, femoral artery peak flow velocity (Δ58.22 mm/s, 95% CI: 13.85-102.60 mm/s, P = 0.0104), RF diameters (Δ0.16 mm, 95% CI: 0.04-0.28 mm, P = 0.0093), myofibrils diameter (Δ0.06 μm, 95% CI: 0.02-0.10 μm, P = 0.006), oxidative muscle fiber percentage (Δ4.84%, 95% CI: 0.15-9.53%, P = 0.0434), mitochondria oxidative phosphorylate capacity ( P < 0.0001). Biomolecules spatial distribution in situ and bioinformatic analyses of transcriptomics suggested COPD-related alteration in metabolites and gene expression, which can be impacted by exercise. Conclusion::COPD rat model had multi-level structure and function impairment, which can be mitigated by exercise.

Objective:To summarize the clinical characteristics of patients with coronavirus disease 2019 (COVID-19) infected with Delta variant, so as to provide further references for clinical diagnosis and treatment.Methods:A real-world study was conducted to analyze the characteristics of 166 COVID-19 patients infected with Delta variant at Guangzhou Eighth People’s Hospital, Guangzhou Medical University.Results:The study enrolled 5 asymptomatic cases, 123 non-severe cases (mild and moderate type), and 38 severe cases (severe and critical type). Among these patients, 69 (41.6%) were male and 97 (58.4%) were female, with a mean age of 47.0±23.5 years. Thirty-nine cases (23.5%) had received 1 or 2 doses of inactivated vaccine. The incidence of severe COVID-19 cases was 7.7% in 2-doses vaccinated patients, which was lower than that of 11.5% in 1-dose and 26.8% in unvaccinated patients. The proportion of severe cases in 2 dose-vaccinated patients was 7.7%, which was lower than that of 11.5% in 1-dose vaccinated patients and 26.8% in unvaccinated patients, but the difference was not significant ( P>0.05). The most common clinical symptom was fever (134 cases, 83.2%), and 39.1% of cases presented with high-grade fever (≥39 °C); other symptoms were cough, sputum, fatigue, and xerostomia. The proportion of fever in severe cases was significantly higher than that of non-severe cases (97.4% vs. 76.4%, P<0.01). Similarly, the proportion of severe cases with high peak temperature (≥39 ℃) () was also higher than that of non-severe cases (65.8% vs. 30.9%, P<0.01). The median minimal Cycle threshold (Ct) values of viral nucleic acid N gene and ORFlab gene were 20.3 and 21.5, respectively, and the minimum Ct values were 11.9 and 13.5, respectively. Within 48 h of admission, 9.0% of cases presented with decreased white blood cell counts, and 52.4% with decreased lymphocyte counts. The proportions of increased C-reactive protein, serum amyloid A, interleukin 6, and interleukin 10 were 32.5%, 57.4%, 65.3%, and 35.7%, respectively. The proportions of elevated C-reactive protein, serum amyloid A and interleukin-6 in severe cases were significantly higher than those in non-severe cases ( P<0.01). Logistic regression analysis showed that older age and higher peak temperature were associated with a higher likelihood of severe cases ( OR>3, 95% CI: 2-7, P<0.01). In terms of treatment, traditional Chinese medicine (TCM) was used in 97.6% of non-severe cases and 100% in severe cases. Other treatments included respiratory and nutritional support, immunotherapy (such as neutralizing antibodies and plasma of recovered patients). The median times from admission to progression to severe cases, of fever clearance, and of nucleic acid conversion were 5 days, 6 days and 19 days, respectively. No deaths were reported within 28 days. Conclusions:The symptoms of Delta variant infection in Guangzhou are characterized by a high proportion of fever, high peak temperature, long duration of fever, high viral load, a long time to nucleic acid conversion, and a high incidence of severe cases. The severe cases exhibit a higher percentage of elderly patients, a longer duration of fever and have a higher fever rate and a higher hyperthermia rate than non-severe cases. Age and hyperthermia are independent risk factors for progression to severe disease. The combination of TCM and Western medicine can control the progression of the disease effectively.

Objective　We established a model by using microfluidic chip that is a horizontal side by side diffusion system through microporous separating three adjacent channels in a triple-culture using neurons,astrocytes,and bEnd.3.Methods　(1)In the in vitro microphysiological system of neurovascular unit,we identified the seed density,seed time,seed sequence and seed method.(2)We adopt the repeated measures data of ANOVA to see whether there is significant difference in the viability when the three cell types are tri-cultured and separately mono-cultured.Results　(1) In the novel in vitro NVU model,the seed density of the neurons,astrocytes and bEnd.3 is 5×10^6~10×10^6 /ml,3×10^5~8×10^5个/ml and 1×10^5~5×10^5/ml.The seed sequence is from neurons to astrocytes to bEnd.3.The seed time is that after the previous seeded cells enter the exponential phase,the next cells will be seeded.(2)We adopt the repeated measures data of ANOVA to see whether there is significant difference in the viability when the three cell types are tri-cultured and separately mono-cultured.Conclusion　In this study,neurons,astrocytes and bEnd.3 were tri-cultured by using microfluidic chip.In this tri-culture model,these three kinds of cells have high cell viability.

Objective To compare the biomechanical stability of different fixation methods for unstable pelvic fractures, so as to provide references for clinical treatment. Methods An unstable pelvic fracture model (Tile C) with the sacroiliac joint dislocation at one side and the pubic rami fracture was constructed via three-dimensional finite element method. In the front of the pelvis, the fracture models were fixed with anterior pelvic Stoppa approach (ASA),subcutaneous anterior pelvic approach (APA), anterior pelvic ilioinguinal approach (AIA) and anterior pelvic external fixation (AEF),and the rear was fixed with sacroiliac joint screw (SIJS）and posterior tension-band plate (PTP). The Von Mises stress and strain distributions of fracture models fixed by different combinations of fixation approaches were analyzed under simulated standing conditions. Results After the models were applied with 500 N vertical load, the maximum stresses at the fracture sites were all reduced, which were smaller than 10 MPa in the front of the pelvis. The maximum stress at the anterior and posterior part of implants in sequence was ASA＜AIA＜AEF＜APA, and the average displacement under the same stress in sequence was ASA＜AIA＜AEF＜APA. Meanwhile, the maximum stresses at the sacroiliac joint and the posterior part of implants in PTP group were significant smaller than those in SIJS group, and the maximum total displacement and vertical displacement in PTP group were also smaller than those in SIJS group. Conclusions Unstable pelvic fractures could be significantly improved when the fracture was fixed by implants in eight combined methods. However, the overall biomechanical properties of the AIA groups were superior to those of the AEF groups and the APA groups. The stability of PTP groups in the treatment of posterior injury was better than that of SIJS groups.

BACKGROUND: Both lentiviral vector and adenoviral vector are considered as good vectors for gene mediation, and their differences in transferring bone morphogenetic protein 2 (BMP-2) into rabbit bone marrow mesenchymal stem cells (BMSCs) are unclear. OBJECTIVE: To compare the duration, efficiency and the deviation of exogenous gene expression after rabbit BMSCs transfection using lentiviral vector and adenoviral vector which are used to mediate enhanced green fluorescent proteins (EGFP) and BMP-2. METHODS: Rabbit BMSCs at passage 5 were exposed to Ad-EGFP-BMP-2 (group A) or Lenti-EGFP-BMP-2 (group B) with multiplicity of infection of 100, as transfection groups. And in control group (group C), the same quality of culture medium was required equivalent to the groups A and B. The expression of EGFP was observed by inverted fluorescence microscope at various time intervals. And the expression of exogenous gene BMP 2 in cells was detected and analyzed by immunohistochemical staining at 72 hours after transfection as well as by western blot at 72 hours, 1, 3 weeks after transfection. RESULTS AND CONCLUSION: The intense green fluorescence emerged under the microscope at 24-48 hours after transfection in group A, which was stronger than group B, reached the peak at 72 hours, and then decreased at 1 week until disappearance at 3 weeks. No EGFP expression was detected in group C. High expression of BMP-2 was found in group A but was dramatically downregulated after 1 week. Group B showed the high expression of EGFP/BMP-2 persisted for a longer period after transfected that even lasted for 3 weeks. Overall, the lentiviral vector and adenoviral vector can efficiently transfect rabbit BMSCs and stably express the target gene of EGFP/BMP-2. Under the same MOI, compared to the adenoviral vector, transfection of lentiviral vector to rabbit BMSCs is more effectively and expression of EGFP/BMP-2 can be persistent in a longer term.

Objective To observe the biocompatibility of rabbit bone marrow mesenchymal stem cells (BMSCs)combined with allogeneic decalcified bone matrix(DBM)after transfecting adenoviral recombinant human bone morphogenetic protein-2(Ad-rhBMP-2).Methods The rabbit allogeneic DBM material was prepared according to the Ursit method.After transfecting Ad-BMP-2 on rabbit bone marrow mesenchymal stem cells,the immunohistochemical was used to detect the expression of BMP-2 in the transfected cells;after 48 h of transfection,the cells were planted on the allograft DBM,then the scanning electron microscopy was used to observe the cell growth and adhesion condition on material,and the proliferation condition of BMSCs was detected by MTT. Results After 48 h of adenoviral transfection,BMSCs could express BMP-2 successfully.The scanning electron microscopy showed that the cells after transfection adhered well and massively proliferated on DBM material.The MTT assay showed that the prolifer-ation condition of the cells after transfection planted on DBM was normal,which showed no statistically significant difference when compared with the control group (P >0.05).Conclusion The Ad-BMP-2 transfection on BMSCs is well biocompatible to allogene-ic DBM.

Objective To evaluate the effect of human bone morphogenetic protein 2 (hBMP-2)/Bone Mesenchymal Stem Cells (BMSCs)/demineralized bone matrix(DBM) on repairing rabbits’femoral head after necrosis and to explore the new treatments for femoral head necrosis. Methods Femoral head necrosis models was established by clinical core decom?pression combined with liquid nitrogen frozen. Then, animals were randomly devided into 4 groups (n=12 per group):Group A were not implanted anything as control group, Group B were implanted with DBM. Group C were implanted with hBMP-2/DBM. Group D were implanted with hBMP-2/BMSCs/DBM. Four rabbits from each group were sacrificed at 4,8 and 12 weeks after surgery to evaluate the the repairing effect of Osteonecrosis of the femoral head (ONFH) through X-ray examina?tion, observation of the specimen and HE staining. Results X-ray revealed defect of femoral head in Group A without clear bone formation. There is a little fibrous hyperplasia and no obvious osteogenic response. By contrast, the femoral head defect areas became fuzzy in group B, group C and group D with new bone trabeculars. And the regenerate phenomenons of group D were significantly better than that of group B and group C of the same time point. As to the Lane-Sandhu X Ray scores, it is lower in group A than that in group B;It is lower in group C than that in group D(P<0.05). There is no statistical difference between Group B and Group C. General observation of the specimen revealed that the femoral head of group A collapsed with drilling holes. The femoral heads of group B and group C showed no collapse but the drilling holes existed. Femoral head in group D was not collapsed and the drilling holes disappeared. HE staining showed that bone trabeculars became ne?crotic and fragmented in Group A with a lot of air trapped cells. There were newborn immature bone trabeculars and osteo? blasts in group B and group C. Group D were of large number of bone cells, fat cells, and newborn mature bone trabeculars. The ratio of empty lacuna is higher in Group A than that in Group B;it is higher in Group C than that in Group D(P<0.05). Conclusion hBMP-2/BMSCs/DBM can induce BMSCs differentiation into osteoblasts after being implanted. It has good re?pairing effect on ONFH with good application prospect.

Objective To culture the rabbit bone marrow derived mesenchymal stem cells (BMSCs) ,and to observe their biologi-cal characteristics in vitro and the expression of BMP2 and EGFP after Ad-EGFP-BMP2 infected on them .Methods To isolate and cultivate BMSCs by density gradient centrifugation and adherent culture in vitro ;the cell cycle and the surface marks were detected by flow cytometer ;rabbit BMSCs were differentiated into the direction of osteogenetic cells by in vitro induction .After transfection , the expression of exogenous gene in the cells was detected by the immunocytochemical staining and Western blot .Results About 56 .84% of rabbit BMSCs cell cycle was in the G1 phase;the D44 expression was positive and the CD45 expression was negative ;af-ter induction by osteogenetic cells ,the Ⅰtype collagen immunohistochemical staining was positive and the alizarin red staining was positive .After transfection ,the strong expression of BMP2 and EGFP in cells was showed by Western blot and the immunocyto-chemical staining .Conclusion rabbit BMSCs are successfully isolated ,cultured and identified to have the ability of osteogenetic dif-ferentiation ;the structured Ad-BMP-2/EGFP can efficiently transfected rabit BMSCs and stably express the target gene of BMP 2 .

Objective To study the effects of short-term cryopreservation on the proliferation ,bio-characteristics and osteogenic capability of rabbit BMSCs and lay the foundation for the further study .Methods The 5th generation of rabbit BMSCs were cryo-preservated by liquid nitrogen for 30 days ,and then thawing the cells to culture it to the 10th generation in vitro ,put the non-cryo-preservated and the same generation BMSCs as the control group .The MTT ,cell cycle ,cell surface marker ,the content of ALP and the immunohistochemical staining for collagen typeⅠ and alizarin red staining for calcium after differentiation induced by osteogene-sis were used to evaluate the proliferation ,bio-characteristic and osteogenic differentiation capability of rabbit BMSCs .Results The growth incubation period of BMSCs after cryopreservated was extended ,but it gradually recover through serial passage .The prolif-eration index and the proportion of BMSCs in G1 phase were 42 .9% ± 3 .4% and 57 .0% ± 3 .4% respectively .The positive rate of cell surface marker of CD44 was 93 .62% ± 1 .05% without expression of CD45 .The contents of ALP(U/gprot) were 6 .73 ± 1 .92 and 15 .99 ± 4 .36 in BMSCs after 7th day and 14th day with osteogenic induction ,respectively .The collagen typeⅠ and alizarin red staining for calcium indicated positive at BMSCs after 14th day and 21th day with osteogenic induction ,respectively .These results showed no significant difference compared with the control group (P>0 .05) .Conclusion Short-term cryopreservation has no obvi-ous impacts on the proliferation ,bio-characteristic and osteogenic capability of BMSCs and it could be used for further study .