Objective·To evaluate the applicability of dual-unit cantilever restorations supported by a single narrow-diameter implant for consecutive missing teeth in the anterior mandibular region.Methods·A simplified mandibular anterior jaw model and a dual-unit cantilever model supported by a single narrow-diameter implant were constructed.The dimensions of the mandibular anterior bone block were set to 20 mm(length),5 mm(width),and 15 mm(height).The narrow-diameter implant used was the Axiom 2.8 two-stage implant,2.8 mm× 10 mm,paired with a 2.5 mm straight abutment.Based on calculations,the edentulous gap ranged from 5.8 mm to 11.6 mm,leading to the creation of seven crown models with mesiodistal widths of 5.8,6.8,7.8,8.8,9.8,10.8,and 11.8 mm.The implant,crowns,and jaw model were assembled using Siemens Nx 12.0 software,and the data were imported into Ansys Workbench 18.0 for finite element analysis.A vertical load of 100 N and a 30° oblique load were applied to simulate occlusal forces.The Von-Mises stress on the implants,as well as the maximum compressive and tensile stresses in the cortical bone and the maximum tensile stress in the cancellous bone,was analyzed to investigate stress distribution under varying cantilever lengths.Results·The implant neck region exhibited the highest stress concentration.As the cantilever length increased,the peak Von-Mises stress on the implants,the maximum tensile stress in the cortical and cancellous bones,and the maximum compressive stress in the cortical bones all increased progressively.However,all stress values remained within physiological limits.The peak Von-Mises stress ranged from 141.52 MPa to 707.17 MPa,below the implant's ultimate tensile strength of 930 MPa.The maximum tensile stress in the cortical bones(with a peak of 60.82 MPa in the 11.8 mm group)was below the cortical bone's tensile strength limit of 100-130 MPa.The maximum compressive stress in the cortical bone(with an absolute maximum value of 129.39 MPa in the 11.8 mm group)was below the cortical bone's compressive strength limit of 170 to 190 MPa(absolute values).The maximum tensile stress in the cancellous bone ranged from 0.84 MPa to 4.70 MPa,which was below or close to its ultimate tensile strength of 2-5 MPa.Conclusion·Dual-unit cantilever restorations supported by a single narrow-diameter implant may represent a viable treatment option for consecutive missing teeth in the anterior mandibular region.

Objective·To evaluate the applicability of dual-unit cantilever restorations supported by a single narrow-diameter implant for consecutive missing teeth in the anterior mandibular region.Methods·A simplified mandibular anterior jaw model and a dual-unit cantilever model supported by a single narrow-diameter implant were constructed.The dimensions of the mandibular anterior bone block were set to 20 mm(length),5 mm(width),and 15 mm(height).The narrow-diameter implant used was the Axiom 2.8 two-stage implant,2.8 mm× 10 mm,paired with a 2.5 mm straight abutment.Based on calculations,the edentulous gap ranged from 5.8 mm to 11.6 mm,leading to the creation of seven crown models with mesiodistal widths of 5.8,6.8,7.8,8.8,9.8,10.8,and 11.8 mm.The implant,crowns,and jaw model were assembled using Siemens Nx 12.0 software,and the data were imported into Ansys Workbench 18.0 for finite element analysis.A vertical load of 100 N and a 30° oblique load were applied to simulate occlusal forces.The Von-Mises stress on the implants,as well as the maximum compressive and tensile stresses in the cortical bone and the maximum tensile stress in the cancellous bone,was analyzed to investigate stress distribution under varying cantilever lengths.Results·The implant neck region exhibited the highest stress concentration.As the cantilever length increased,the peak Von-Mises stress on the implants,the maximum tensile stress in the cortical and cancellous bones,and the maximum compressive stress in the cortical bones all increased progressively.However,all stress values remained within physiological limits.The peak Von-Mises stress ranged from 141.52 MPa to 707.17 MPa,below the implant's ultimate tensile strength of 930 MPa.The maximum tensile stress in the cortical bones(with a peak of 60.82 MPa in the 11.8 mm group)was below the cortical bone's tensile strength limit of 100-130 MPa.The maximum compressive stress in the cortical bone(with an absolute maximum value of 129.39 MPa in the 11.8 mm group)was below the cortical bone's compressive strength limit of 170 to 190 MPa(absolute values).The maximum tensile stress in the cancellous bone ranged from 0.84 MPa to 4.70 MPa,which was below or close to its ultimate tensile strength of 2-5 MPa.Conclusion·Dual-unit cantilever restorations supported by a single narrow-diameter implant may represent a viable treatment option for consecutive missing teeth in the anterior mandibular region.

Grassroots communities, as the forefront of the transformation of national system and mechanism, the reformation of social structure, the change of interest pattern, and the transition of ideological consciousness, have long been the focus of government work, academic research, and social practitioners. Based on the theory of collaborative governance, aiming at the problems existing in the emergency management of public health emergencies in grassroots communities at present, this paper put forward the construction measures of public health emergency collaborative governance system with grassroots communities as the core, including improving the grassroots community emergency management organizational structure, consolidating the standardized foundation of grassroots community emergency collaborative management, enhancing the awareness of grassroots community emergency collaborative management, and strengthening the interactivity of the grassroots community information communication system. It is hoped to provide necessary reference for promoting the reform of public health emergency governance system.

Objective:Anatomical study of the cross-donor flap pedicled with the peroneal artery and the discussion of the effect of clinical application, so as to describe a new method for the repair of large-area soft tissue defects in the foot and ankle.Methods:From June 2016 to August 2019, 12 specimens of adult lower limbs were studied. The popliteal arteries were perfused with perchloroethylene-ethyl acetate-lead oxide and red perchloroethylene-ethyl acetate. The origin, number, outer diameter, course and distribution of perforating branches of the peroneal artery were anatomically observed. The source, distribution and anastomosis of the skin nutrient vessels in the posterolateral area of the calf were also studied. Relationship of the blood supply between the peroneal arteries and veins and the nutritional vessels of the sural nerve were observed. In 9 patients, the peroneal artery and vein were designed as the pedicle of cross-donor flap in the repair of large soft tissue defects of foot and ankle. The patients were entered follow-up through outpatient visits and telephone interviews.Results:Among the 12 adult specimens of lower limbs, there were 65 perforating branches from the peroneal artery, 4-7 branches on each side, with an average of (5.41±1.00) branches. The diameter of the penetrating deep fascia was(1.07±0.36) mm. The perforator branches were mostly distributed in 3 sections of 4.0-11.0 cm, 16.0-21.0 cm and 24.0-27.0 cm away from the lateral malleolus, accounting for 48%, 24% and 17% of the total number of perforators, respectively. The outer diameters of the perforator vessels were (0.92±0.26)(0.56-1.68) mm, (1.32±0.38)(0.60-2.14) mm, and (0.98±0.28)(0.62-1.36) mm. The length of the pedicle of the perforator vessels were (3.91±0.96)(2.15-5.78) cm, (5.34±0.50)(4.01-5.85) cm, and (3.31±1.15)(2.16-5.66) cm. The perforating branches in the 3 sections appeared constantly. The diameter of the vessels was≥0.5 mm with an average length of at(4.19±1.16)(2.15-5.85) cm. The vascular network of the flap in the posterolateral area of the calf was mainly composed of subdermal vascular network and deep fascial vascular network. The deep fascia vascular network in the posterolateral area of the calf had 3 obvious longitudinal chains, including the medial sural neurotrophic vascular chain, the small saphenous vein-sural nerve communicating branch vascular chain and the lateral sural neurotrophic vascular chain, which took the nutrient blood supply from the perforating branches of the peroneal artery also formed a longitudinal and transverse anastomosis between the perforating branches of the peroneal artery. In the clinical trials performed on 9 patients, all soft tissue defects of foot and ankle were repaired. The composite tissue flap survived without infection or necrosis. The follow-up was lasted for 12 months to 3 years. The postoperative function and the donor site appearance were good and the patients walked normally. According to the American Orthopaedic Foot and Ankle Association(AOFAS) foot scoring standard, the function of affected feet were evaluated. Five patients were excellent and 4 were good.Conclusion:The cross-donor flaps pedicled with peroneal arteries and veins has sufficient blood supply and a large area. It provides a method for the repair of large-area soft tissue defects in the foot and ankle.

Tricuspid valve, also known as "forgotten valve" because of the high natural and surgical mortality. Transcatheter tricuspid valve replacement is an innovative surgical method to treat tricuspid regurgitation, which improves the prognosis of patients and is gradually being popularized in clinics. However, postoperative pulmonary complications are still the main causes affecting the rapid recovery and death. More and more medical experts begin to use preoperative inspiratory muscle training to reduce postoperative pulmonary complications and improve the quality of life of patients after cardiac surgery. However, there was no report on the effect of preoperative inspiratory muscle training on pulmonary complications after transcatheter tricuspid valve replacement. Therefore, for the first time, we boldly speculate that inspiratory muscle training can reduce pulmonary complications after transcatheter tricuspid valve replacement, and put forward suggestions for its treatment mechanism and strategy. But this rehabilitation intervention lacks practical clinical research. Unknown challenges may also be encountered, which may be a new research direction.

Background and objective It is unknown that the postoperation fast-track recovery and in hospital cost of the lobectomy in lung cancer, we explored the inlfuencing factor of postoperative fast-track recovery and in hospital cost atfer undergoing lobectomy for lung cancer. Methods We retrospectively reviewed the medical records of all patients (n=176) who underwent lobectomy for lung cancer between January 2010 and November 2011 by a thoracic surgeon. Results hTe hospital costs of video-assisted thoracic surgery (VATS) lobectomy (47,308.21 ￥) is signiifcantly higher than open lobectomy (45,664.31 ￥)(P=0.007). hTe hospital costs of body mass index (BMI)≥24 kg/m2 (51,186.99 ￥) is signiifcantly higher than BMI<24 kg/m2 (41,701.64 ￥)(P=0.032). hTe hospital stay of VATS lobectomy (5.70 d) is signiifcantly less than open lobectomy (7.10 d)(P<0.001). Conclusion hTese ifndings indicate that preoperative pulmonary rehabilitation and VATS lobectomy is contrib-uted to fast-track recovery for patients who undergo lobectomy, but increase the hospital costs.

Postnatal cerebral development is a complicated biological process precisely controlled by multiple genes. To understand the molecular mechanism of cerebral development, we compared dynamics of mouse cerebrum transcriptome through three developmental stages using high-throughput RNA-seq technique. Three libraries were generated from the mouse cerebrum at infancy, adolescence and adulthood, respectively. Consequently, 44,557,729 (infancy), 59,257,530 (adolescence) and 72,729,636 (adulthood) reads were produced, which were assembled into 15,344, 16,048 and 15,775 genes, respectively. We found that the overall gene expression level increased from infancy to adolescence and decreased later on upon reaching adulthood. The adolescence cerebrum has the most active gene expression, with expression of a large number of reg-ulatory genes up-regulated and some crucial pathways activated. Transcription factor (TF) analysis suggested the similar dynamics as expression profiling, especially those TFs functioning in neurogenesis differentiation, oligodendrocyte lineage determination and circadian rhythm regula-tion. Moreover, our data revealed a drastic increase in myelin basic protein (MBP)-coding gene expression in adolescence and adulthood, suggesting that the brain myelin may be generated since mouse adolescence. In addition, differential gene expression analysis indicated the activation of rhythmic pathway, suggesting the function of rhythmic movement since adolescence;Furthermore, during infancy and adolescence periods, gene expression related to axon repulsion and attraction showed the opposite trends, indicating that axon repulsion was activated after birth, while axon attraction might be activated at the embryonic stage and declined during the postnatal develop-ment. Our results from the present study may shed light on the molecular mechanism underlying the postnatal development of the mammalian cerebrum.

Histone H3 lysine 4 trimethylation (H3K4me3) is well known to occur in the promoter region of genes for transcription activation.However,when investigating the H3K4me3 profiles in the mouse cerebrum and testis,we discovered that H3K4me3 also has a significant enrichment at the 3' end of actively transcribed (sense) genes,named as 3′-H3K4me3.3′-H3K4me3 is associated with ～15％ of protein-coding genes in both tissues.In addition,we examined the transcriptional initiation signals including RNA polymerase II (RNAPII)binding sites and 5′-CAGE-tag that marks transcriptional start sites.Interestingly,we found that 3′-H3K4me3 is associated with the initiation of antisense transcription.Furthermore,3′-H3K4me3 modification levels correlate positively with the antisense expression levels of the associated sense genes,implying that 3′-H3K4me3 is involved in the activation of antisense transcription.Taken together,our findings suggest that H3K4me3 may be involved in the regulation of antisense transcription that initiates from the 3′ end of sense genes.In addition,a positive correlation was also observed between the expression of antisense and the associated sense genes with 3'-H3K4me3 modification.More importantly,we observed the 3'-H3K4me3 enrichment among genes in human,fruitfly and Arabidopsis,and found that the sequences of 3'-H3K4me3-marked regions are highly conserved and essentially indistinguishable from known promoters in vertebrate.Therefore,we speculate that these 3'-H3K4me3-marked regions may serve as potential promoters for antisense transcription and 3′-H3K4me3 appear to be a universal epigenetic feature in eukaryotes.Our results provide a novel insight into the epigenetic roles of H3K4me3 and the regulatory mechanism of antisense transcription.

The global features of H3K4 and H3K27 trimethylations (H3K4me3 and H3K27me3) have been well studied in recent years,but most of these studies were performed in mammalian cell lines.In this work,wegenerated the genome-wide maps of H3K4me3 and H3K27me3 of mouse cerebrum and testis using ChlP-seq and their high-coverage transcriptomes using ribominus RNA-seq with SOLiD technology.We examined the global patterns of H3K4me3 and H3K27me3 in both tissues and found that modifications are closely-associated with tissue-specific expression,function and development.Moreover,we revealed that H3K4me3 and H3K27me3 rarely occur in silent genes,which contradicts the findings in previous studies.Finally,we observed that bivalent domains,with both H3K4me3 and H3K27me3,existed ubiquitously in both tissues and demonstrated an invariable preference for the regulation of developmentally-related genes.However,the bivalent domains tend towards a "winner-takes-all" approach to regulate the expression of associated genes.We also verified the above results in mouse ES cells.As expected,the results in ES cells are consistent with those in cerebrum and testis.In conclusion,we present two very important findings.One is that H3K4me3 and H3K27me3 rarely occur in silent genes.The other is that bivalent domains may adopt a "winner-takes-all" principle to regulate gene expression.