Dental implant is an advanced prosthodontic treatment widely accepted by patients with missing tooth. However, peri-implant bone loss is still an important reason which limits wider application of the implants to a certain extent. Bisphosphonates is an osteoclastic bone resorption inhibitor that is widely used in clinical practice with the function of inhibiting bone resorption and increasing bone density. As the defect of systemic BPs treatment, local application of BPs in implant has become a research hotspot recently. Calcium phosphate ceramics, polylactic acid, fibrinogen film and collagen membrane have been reported as BPs carriers. This article summarizes the researches on the mechanism of bone regulation and local delivering system of BPs.
Administration, Topical ; Bone Density Conservation Agents ; administration & dosage ; Bone Remodeling ; drug effects ; physiology ; Dental Implantation, Endosseous ; methods ; Dental Implants ; Diphosphonates ; administration & dosage ; Humans

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants continue to spread around the world, posing a great threat to global economic and public health. Influenza A virus, a major cause of influenza, has a wide host range and evolves rapidly. Influenza pandemics, which occur every 20 to 40 years, annual seasonal influenza epidemics, severe influenza and animal influenza viruses are all serious threats to public health. Clinical manifestations of infections caused by the two pathogens are very similar. It is of great significance to develop an effective bivalent vaccine for controlling alternating epidemics or co-infection of the two pathogens. This article reviewed the progress in the development of bivalent vaccines against SARS-CoV-2 and influenza A virus based on different platforms.

Objective To analyze survival and recurrence rates of patients with Masaoka stage Ⅲ thymoma and to explore the prognostic factors.Methods Between September 1965 and December 2010,a total of 111 patients with stage Ⅲ thymoma treated in our hospital were retrospectively analyzed.Sixty-eight patientsreceived comple te rescction ± radiotherapy,whilc 23 patients received incomplete resection ±radiotherapy and 20 patients received biopsy ± radiotherapy.Eighty-seven patients received postoperative radiotherapy (12 patients received preoperative radiotherapy) while 24 patients received surgery alone.Results The median follow-up time was 66 months (5-540) with a follow-up rate of 92.5％ (111/120).Compared with incomplete resection ± radiotherapy and biopsy ± radiotherapy,the 5-year overall survival (OS) (88％ vs.59％ and 57％,x2 =12.11,P =0.002),disease free survival (DFS) (74％ vs.40％ and 41％,x2 =11.49,P =0.003) and disease specific survival (DSS) (94％ vs.69％ and 60％,x2 =10.95,P =0.004) could be improved with complete resected ± radiotherapy.Compared with surgery alone,postoperative radiotherapy did not improve OS,DFS and DSS (55％ vs.77％ (x2 =1.01,P =0.316),61％vs.61％ (x2 =0.12,P =0.729) and 72％ vs.85％ (x2 =0.27,P =0.601),respectively).For the 68 patients received complete resection,radiotherapy after complete resection (56 patients) did not improve OS,DFS and DSS (82％ vs.89％ (x2 =0.31,P =0.576),72％ vs.81％ (x2 =0.05,P=0.819) and 89％vs.95 ％ (x2 =0.05,P =0.825),respectively) compared with surgery alone (8 patients).Conclusions Stage Ⅲ thymoma patients received complete resection had better outcome than patients received incomplete resection or biopsied only.The role of postoperative radiotherapy is still controversial for stage Ⅲ thymoma,randomized clinical trial is needed

Objective:To construct a bivalent DNA vaccine against SARS-CoV-2 and influenza A virus H3N2 and to evaluate its immunogenicity in mice.Methods:The coding sequences for spike 1 (S1) protein of SARS-CoV-2 Beta variant and hemagglutinin (HA) of influenza A virus Cambodia (H3N2) strain were codon-optimized and synthesized. The two coding genes were ligated by the self-cleaving 2A peptide using over-lapping PCR to construct S1-2A-HA fragment, which was inserted into pVRC vector to construct the bivalent DNA vaccine, named as pVRC-S1-2A-HA. Indirect immunofluorescence assay (IFA) and Western blot were performed to detect the expression of S1 and HA proteins. BALB/c mice were immunized with pVRC-S1-2A-HA by intramuscular injection and electroporation. The humoral immune responses induced in mice were detected by indirect ELISA, pseudovirus neutralization assay and hemagglutination inhibition assay. Cellular immune responses were detected by IFN-γ ELISPOT, intracellular cytokine staining (ICS) and cytometric bead array (CBA).Results:The bivalent DNA vaccine pVRC-S1-2A-HA could express S1 and HA proteins in vitro. Specific cellular immune responses against S1 protein and specific IgG antibody against HA protein were significantly induced in mice with single-dose immunization. The antigen-specific immunity was significantly enhanced after booster immunization. The geometric mean titer (GMT) of specific IgG antibody increased to 3 251 for S1 protein and 45 407 for HA protein after two-dose immunization. Moreover, the S1-specific T cells increased to 1 238 SFC/10 6 cells. ICS results indicated that the booster vaccination induced CD4 + T and CD8 + T cells to produce IL-2, IFN-γ and TNF-α in mice. The secretion of various cytokines including IL-2, IL- 4, IL-6, IL-10 and IFN-γ in mouse splenocytes was induced after single-dose immunization. Conclusions:A bivalent DNA vaccine against SARS-CoV-2 and influenza A virus H3N2 was constructed and could induce S1- and HA-specific humoral and cellular immune responses in mice, suggesting the great potential of it for further development and application.

Objective:To construct a novel respiratory syncytial virus (RSV) vaccine based on a recombinant influenza virus vector and evaluate its immune protective effects in mice.Methods:A recombinant H1N1 influenza A virus (IAV) expressing the extracellular domain (Gecto) of RSV A2 G protein was constructed and rescued, named as PR8NAGecto/WSN. After in vitro verification of the Gecto expression and PR8NAGecto/WSN growth kinetics, a single dose of PR8NAGecto/WSN was used to immunize BALB/c mice through intranasal administration to evaluate the efficacy of PR8NAGecto/WSN by assessing humoral (IgG, neutralizing antibody), mucosal (IgA) and cellular immunity (IFN-γ ELISPOT). Four weeks after immunization, the mice were challenged with RSV A2 or RSV B9320 to evaluate the protective effects of PR8NAGecto/WSN by analyzing mouse body weight changes, lung tissue virus titers and pathological changes. Results:A single-dose intranasal immunization with PR8NAGecto/WSN induced robust humoral, mucosal and cellular immunity in mice. Moreover, the mice in the immunized group had lower lung virus loads and mild lung pathological damages following the challenge with RSV A or RSV B subtype as compared with the control group.Conclusions:A single-dose intranasal immunization with PR8NAGecto/WSN induces robust immunity and provide protection against RSV A and B challenges in mice. This study provides new ideas and reference for the development of novel mucosal vaccines against RSV.

Objective To evaluate the current status of radioactive occupational hazards in the construction of some medical institutions in Tianjin, discover existingproblems and deficiencies, and provide a technical basis for radiation protection management. Methods Based on the requirements of relevant regulations and standards, we comprehensivelyevaluated the results of the pre-evaluation and control effect evaluation of 81 radioactive occupational hazards in Tianjin. Results Among the 35 proposed protective measures for pre-evaluation of radiation occupational hazards constructionprojects, the lowest compliance rate is warning signs and personal protective equipment. Among the 46 construction projects of radioactive occupational hazard control evaluation, the pass rate of protective measures was between 73.9% and 100%, with the lowest pass rate for personal protective equipment. Besides, the pass rate of radiation protectionmanagement evaluation was 95.7% ～ 100%, with the lowest pass rate for the protection management system.The initial inspectionpass rateof the equipment quality control acceptancewas 98.6%, while the pass rate was 97.1% for the relevant workplace radiation protection during the initial inspection. Conclusion The pre-evaluation completion rate of radiological occupational hazard evaluation in Tianjin medical institution construction project, unilateral and area of construction room, workplace layout and zoning, ventilation, shielding measures, personal dose management and occupational health inspection all meet the requirements of regulations and standards. However, there are still some deficiencies in the personal protective equipment, warning signs and the radiation protection management system. Therefore, the regulatory department should further strengthen the evaluation of medical institutions, especially the key supervision and management of non-conformities.

Objective To analyze the status quo and existing problems of radiation protection for veterinary X-ray facilitiesin Beijing-Tianjin region, China, and to provide a basis for improving radiation protection management level. Methods According to the requirements of the Technical guidelines for status quo assessment of occupational hazard of the employing unit (AQ/T 4270—2015), the study performed status quo assessment on the workplaces of veterinary X-ray facilities in 16 pet hospitals in Beijing-Tianjin region, and comprehensively analyzed the impact of the workplaces on the health of radiation workers and the public. Results In terms of personnel management, the pass rates of occupational health management post setting, personnel training, personal protective equipment, individual monitoring of occupational external exposure, notification of occupational hazards, and occupational health surveillance were 100%, 81.3%, 100%, 75%, 37.5%, and 25%, respectively. In terms of workplace management, most workplaces had reasonable layout and zoning and complete protection and emergency devices. However, there were some problems in some places, such as non-standard radiation warning signs, no notice board of occupational hazards, and no radiation protection testing. In terms of document management, all institutions had imperfect system documents. Conclusion The workplaces of veterinary X-ray facilities in 16 institutions basically meet the requirements for radiation protection, but there are also some problems, such as inadequate management of personnel and workplace radiation protection, and imperfect system documents. Institutions should strengthen the study of radiation protection knowledge. The competent authorities should strengthen supervision, formulate corresponding standards for radiation protection, enhance training, and improve the professional level of staff.