With the extensive application of nuclear technology in industry, agriculture, and medicine, the safety issues associated with neutron radiation have become increasingly prominent. Due to their high penetrability and strong ionization effect, neutrons can cause serious health risks by directly damaging DNA or inducing secondary γ radiation. Therefore, the neutron radiation protection has become a core challenge in radiation protection, especially the research and development of neutron shielding materials. To ensure the safe development of nuclear technology, neutron shielding materials are indispensable and constitute a fundamental core technology for radiation protection. This paper reviews the theory of neutron radiation protection and the research progress of neutron shielding materials, with a focus on the current application status and existing problems of neutron shielding materials. This article also discusses the future development trends. This review aims to provide theoretical support and technical references for the safe application and development of nuclear technology.

As the main means of mastication, teeth can withstand countless functional contacts. The mechanical properties of teeth are closely related to their tissue structure. Enamel and dentin have a high hardness and modulus of elasticity, and their graded structure allows them to withstand bite forces without being susceptible to fracture. When tooth tissue is defective, full crown restoration is often needed to restore the normal shape and function of the tooth. Metal materials, ceramic materials, and polyetheretherketone (PEEK) materials are commonly used for crown restoration. Metal materials have certain disadvantages in terms of aesthetics and are relatively rarely used in clinical practice. Ceramic materials with different compositions exhibit differences in performance and aesthetics, but their elastic modulus and hardness are much higher than those of dental tissue, resulting in mismatching mechanical properties. In contrast, the elastic modulus of PEEK is lower than that of tooth tissue and similar to that of bone tissue, but its properties can be improved by fiber reinforcement. Notably, when the mechanical properties of a restoration material and tooth tissue are not fully matched, the interface between them often forms a potential weak link, which ultimately affects the stability and long-term effect of the restoration. This article introduces the mechanical properties and corresponding structural characteristics of enamel and dentin. On this basis, the advantages and limitations of existing restoration materials are analyzed, and the possibility of biomimetic design of full crowns is further explored.

Objective:To evaluate the clinical application of urine sediment score (USS) in early diagnosis, etiological differentiation, staging and prognosis of acute kidney injury (AKI), and to investigate the diagnostic efficacy of independent USS and its combination with blood urea nitrogen(Bun) serum creatinine(sCr) and uric acid(UA) in AKI.Methods:From August 23 to September 28, 2023, 9 020 morning urine samples of hospitalized patients in the First Hospital of Jilin University were detected by Sysmex UF5000.A total of 3 226 ssamples with small and round cell (SRC) > 1/μl and/or CAST>1/μl were screened for microscopic examination, and 404 cases with positive renal tubular epithelial cells and/or cast were enrolled in this study. There were 218 males and 186 females, aged 59.5 (49.0, 71.0) years. The 404 cases were divided into the USS AKI group (345 cases) and the USS non-AKI group (59 cases) according to the USS results based on the microscopic findings. According to Kidney Disease: Improving Global Outcomes (KDIGO) criteria, they were divided into KDIGO criteria AKI group (63 cases) and KDIGO criteria non-AKI group (341 cases), and the AKI group was divided into renal AKI group (33 cases) and non-renal AKI group (30 cases). According to the clinical diagnosis recorded in the medical records, they were divided into clinically diagnosed AKI group (29 cases) and clinically diagnosed non-AKI group (375 cases).The χ 2 test or Fisher exact test was used to compare USS in different AKI causes and stages. Logistic regression was used to calculate the odds ratio of renal AKI and stage 3 AKI. The area under the receiver operating characteristic curve was used to evaluate the sensitivity and specificity of USS, sCr, UA and Bun alone and in combination in the diagnosis of AKI, and the best cut-off value, sensitivity and specificity in the diagnosis of AKI were calculated. P < 0.05 was considered statistically significant. Results:The USS was used to identify the etiology of KDIGO standard AKI group,and there were significant differences in USS between renal AKI group and non-renal AKI group (χ 2=11.070, P<0.001). Compared to USS=1, the odds ratio of renal AKI was 8.125 when USS≥2 (95% CI 2.208—29.901). There was a statistically significant difference in the comparison of USS between groups in each stage of the AKI staging study based on USS (χ 2=15.724, P<0.05). Compared to USS=1, the odds ratio of stage 3 AKI was 9.714 when USS≥2 (95% CI 1.145-82.390). The AUC of independent USS in the diagnosis of AKI was 0.687 (95% CI 0.618-0.757, P<0.001), the specificity was 65.7% and the sensitivity was 61.9%. The AUC of USS combined with Bun, sCr, UA in the diagnosis of AKI was 0.794 (95% CI 0.608-0.980, P<0.05), the specificity was 82.4%, and the sensitivity was 88.9%. Conclusions:There wasan increased likelihood of renal AKI or stage 3 AKI while USS≥2,and whose combination with Bun, sCr and UA will improve the diagnostic efficiency of AKI.

Odontogenic maxillary sinusitis(OMS)is a subtype of maxillary sinusitis(MS).It is actually inflammation of the maxillary sinus that secondary to adjacent infectious maxillary dental lesion.Due to the lack of unique clinical features,OMS is difficult to distinguish from other types of rhinosinusitis.Besides,the characteristic infectious pathogeny of OMS makes it is resistant to conventional therapies of rhinosinusitis.Its current diagnosis and treatment are thus facing great difficulties.The multi-disciplinary cooperation between otolaryngologists and dentists is absolutely urgent to settle these questions and to acquire standardized diagnostic and treatment regimen for OMS.However,this disease has actually received little attention and has been underrepresented by relatively low publication volume and quality.Based on systematically reviewed literature and practical experiences of expert members,our consensus focuses on characteristics,symptoms,classification and diagnosis of OMS,and further put forward multi-disciplinary treatment decisions for OMS,as well as the common treatment complications and relative managements.This consensus aims to increase attention to OMS,and optimize the clinical diagnosis and decision-making of OMS,which finally provides evidence-based options for OMS clinical management.

Objective : To investigate the effects of angiopoietin 4 (ANGPT4) on the odontogenic differentiation of human dental pulp stem cells. Methods : This study has been reviewed and approved by the Ethics Committee, and informed consent has been obtained from patients. Human premolars were fixed, decalcified, dehydrated, embedded, and sectioned. Immunofluorescence staining was used to observe the expression and localization of ANGPT4. Human dental pulp stem cells (hDPSCs) were isolated and cultured in vitro. The growth state and morphology of hDPSCs were observed under an inverted phase contrast microscope. The expression of cell surface-related molecular markers was detected by flow cytometry. Alkaline phosphatase and alizarin red S staining were used to detect the odontogenic differentiation potential of hDPSCs. Oil-red O staining was used to detect the adipogenic differentiation potential of hDPSCs. RNA was extracted from hDPSCs at different time points after odontogenic induction, and RT-qPCR was used to analyze the mRNA expression of ANGPT4 and odontogenic-related genes during the odontogenic differentiation of hDPSCs in vitro. siRNA gene silencing technology was used to silence the expression of ANGPT4 in hDPSCs, and the silencing efficiency was detected by RT-qPCR and Western Blot. After silencing ANGPT4 in hDPSCs for 24 h, odontogenic induction was performed. Alkaline phosphatase and alizarin red S staining were performed on the 7th and 14th of induction to detect the odontogenic differentiation ability of hDPSCs after silencing ANGPT4 Results : Immunofluorescence staining of human premolars showed that ANGPT4 was expressed in odontoblasts and sub-odontoblastic cell-rich zone. hDPSCs were in good condition after 14 days of isolation and culture. Under the microscope, multiple cell colonies were observed, and the cell morphology was uniform and long spindle-shaped. The results of flow cytometry showed that hDPSCs expressed mesenchymal stem cell markers CD105 (90.42%) and CD90 (97.15%), but did not express hematopoietic cell markers CD45 (0.01%) and CD34 (0.08%). After odontogenic and adipogenic induction of hDPSCs, alkaline phosphatase staining, alizarin red S staining and oil red O staining were positive. The results of RT-qPCR after the odontogenic induction of hDPSCs showed that ANGPT4 was highly expressed on the 5th, 7th, 11th and 14th days of differentiation of hDPSCs (P<0.05), with the highest expression level on the 5th day. After hDPSCs were transfected with si-ANGPT4, the expression of ANGPT4 mRNA and protein was significantly down-regulated (P<0.05). The results of alkaline phosphatase staining showed that ALP staining intensity and area in the si-ANGPT4 group were significantly lower than those in the negative control. Alizarin red S staining showed that the formation of calcium nodules in the si-ANGPT4 group was significantly lower than that in the negative control. Conclusion ANGPT4 was expressed in odontoblasts and sub-odontoblastic cell-rich zone of human premolars. ANGPT4 may be a factor to promote the odontogenic differentiation of hDPSCs.

The biological samples of oral genetic diseases and rare diseases are extremely precious. Collecting and preserving these biological samples are helpful to elucidate the mechanisms and improve the level of diagnose and treatment of oral genetic diseases and rare diseases. The standardized construction of biobanks for oral genetic diseases and rare diseases is important for achieving these goals. At present, there is very little information on the construction of these biobanks, and the standards or suggestions for the classification and coding of biological samples from oral and maxillofacial sources, and this is not conducive to the standardization and information construction of biobanks for special oral diseases. This consensus summarizes the background, necessity, principles, and key points of constructing the biobank for oral genetic diseases and rare diseases. On the base of the group standard "Classification and Coding for Human Biomaterial" (GB/T 39768-2021) issued by the National Technical Committee for Standardization of Biological Samples, we suggest 76 new coding numbers for different of biological samples from oral and maxillofacial sources. We hope the consensus may promote the standardization, and smartization on the biobank construction as well as the overall research level of oral genetic diseases and rare diseases in China.

Distraction osteogenesis (DO) is widely used for bone tissue engineering technology. Immune regulations play important roles in the process of DO like other bone regeneration mechanisms. Compared with others, the immune regulation processes of DO have their distinct features. In this review, we summarized the immune-related events including changes in and effects of immune cells, immune-related cytokines, and signaling pathways at different periods in the process of DO. We aim to elucidated our understanding and unknowns about the immunomodulatory role of DO. The goal of this is to use the known knowledge to further modify existing methods of DO, and to develop novel DO strategies in our unknown areas through more detailed studies of the work we have done.
Bone Regeneration/physiology* ; Bone and Bones ; Osteogenesis/physiology* ; Osteogenesis, Distraction/methods* ; Tissue Engineering

Pathological diagnosis of salivary gland tumors is one of the most challenging areas in all head and neck surgical pathology. The classification of salivary gland tumors was updated in the 5th edition of the World Health Organization Classification of Head and Neck Tumours, most of which were based on their molecular pathological characteristerics. This new classification features a description of several new entitiesamong benign and malignant neoplasms, salivary gland tumors with updated naming or diagnostic criteria, and lesions deleted from this section, etc.This present review focuses on the updates and changes in the new classification of salivary gland tumors, and provides some reference for head and neck surgeons and pathologists.
Humans ; Head and Neck Neoplasms ; Salivary Gland Neoplasms/pathology* ; Salivary Glands ; World Health Organization

Currently, titanium alloys are widely used in the field of stomatology; however, owing to long-term exposure to a complex microbial environment, dental plaques easily form on the surface of the materials, affecting the use efficiency and the service life of the materials. The antibacterial titanium alloy is a new kind of titanium alloy with antimicrobials added through surface modification or overall modification. Based on the location of antibacterial agents in titanium alloy materials, antibacterial titanium alloys can be divided into coating and alloy types. The antibacterial effect of coated antibacterial titanium alloy is good, but the disadvantage is that most of the coatings are not wear-resistant. The widely-used antibacterial agent of the alloy type is metal elements, which can be evenly distributed in the alloy, and the antibacterial properties are stable and long-lasting. Based on whether antibacterial agents can be released, antibacterial titanium alloys can be further divided into active antibacterial and passive antibacterial types. Active antibacterial type titanium alloys can release loaded antibacterial agents, and the antibacterial effect is more obvious, but the release duration of antibacterial agents is relatively short. Passive antibacterial titanium alloys exhibit an antibacterial effect by contact sterilization or inhibition of bacterial adhesion instead of releasing antibacterial agents. The antibacterial titanium alloy can inhibit the adhesion of bacteria on the surface of the material and prolong the service life of oral orthodontic appliances, implants and titanium plates. Moreover, the mechanical properties of the titanium alloy after antibacterial modification are not significantly affected, and the addition of antibacterial agents such as hydroxyapatite can increase the osteogenic function of the material. Therefore, the alloy has good application prospects in the fields of dental implant, orthodontic treatment and oral and maxillofacial surgery. However, most of the current studies on antibacterial titanium alloys are in vitro experiments, and their long-term clinical effects and antibacterial mechanisms are still unclear and need further study.

Nanomaterial-based drug sustainable release systems have been tentatively applied to bone regeneration. They, however, still face disadvantages of high toxicity, low biocompatibility, and low drug-load capacity. In view of the low toxicity and high biocompatibility of polymer nanomaterials and the excellent load capacity of hollow nanomaterials with high specific surface area, we evaluated the hollow polydopamine nanoparticles (HPDA NPs), in order to find an optimal system to effectively deliver the osteogenic drugs to improve treatment of bone defect. Data demonstrated that the HPDA NPs synthesized herein could efficiently load four types of osteogenic drugs and the drugs can effectively release from the HPDA NPs for a relatively longer time in vitro and in vivo with low toxicity and high biocompatibility. Results of qRT-PCR, ALP, and alizarin red S staining showed that drugs released from the HPDA NPs could promote osteogenic differentiation and proliferation of rat bone marrow mesenchymal stem cells (rBMSCs) in vitro. Image data from micro-CT and H&E staining showed that all four osteogenic drugs released from the HPDA NPs effectively promoted bone regeneration in the defect of tooth extraction fossa in vivo, especially tacrolimus. These results suggest that the HPDA NPs, the biodegradable hollow polymer nanoparticles with high drug load rate and sustainable release ability, have good prospect to treat the bone defect in future clinical practice.
Animals ; Bone Regeneration ; Indoles ; Nanoparticles ; Osteogenesis ; Pharmaceutical Preparations ; Polymers ; Rats