Advances in ceramics for tooth repair: From bench to chairside

OBJECTIVES

To give a comprehensive review of advancement in dental ceramics, fabrication methods, and the challenges associated with clinical application.

DATA, SOURCES AND STUDY SELECTION

Researches on chemical composition, biomechanical behaviors, optical properties, bonding strategies and fabrication methods were included. The search of articles was independently conducted by two authors in the PubMed, Scopus, Medline and Web of Science.

CONCLUSIONS

Dental ceramics have shown significant advancements in terms of esthetics and function. However, improving fracture toughness without compromising optical properties remains a challenge. Repairing fractured zirconia or glass-matrix ceramic prostheses with the same material is difficult due to the sintering process. Developing innovative bonding techniques that provide strong and long-lasting bonding strength between ceramics and tooth structures poses a recurring obstacle.

CLINICAL SIGNIFICANCE

Despite the emergence of dental ceramics and fabrication techniques, certain limitations such as susceptibility to brittleness and fracture still exist. Therefore, the current review provided valuable information around the advanced dental ceramics in tooth repair. The laboratory test data and the clinical outcome are also presented in details, aiming to guide clinicians in making informed decisions regarding ceramic restorations.

[Interpretation of global lung cancer statistics]

Lung cancer remains one of the leading cause of global cancer-related mortality, posing a significant burden of disease. Tobacco exposure stands as the foremost risk factor for lung cancer. Since the 1960, global efforts have gradually been implemented to control tobacco exposure, consequently reducing tobacco exposure levels within populations. This shift in exposure levels may have altered the epidemiological characteristics of lung cancer globally. This study aims to describe global lung cancer incidence data across five dimensions: age, gender, region, stage at diagnosis, and survival status, using global cancer registry data and relevant research findings. The objective is to elucidate the current epidemiological features of lung cancer worldwide, providing a scientific basis for lung cancer prevention and control. Furthermore, this study offers corresponding measures and recommendations for lung cancer prevention and control, aligning with the three-tiered cancer prevention strategy. Findings indicate that the incidence and mortality burden of lung cancer is significantly higher among the elderly population (aged 65 years and above) compared to the working-age population (aged 15-64 years). The aged-standardized incidence rate of lung cancer remains higher in males than in females, but the overall aged-standardized incidence rate of lung cancer in males shows a declining trend, while that in females shows an increasing trend. Regions with high and very high human development index (HDI) exhibit a substantially higher incidence and mortality burden of lung cancer compared to regions with low and very low HDI. Japan ranks highest in the diagnosis of stage Ⅰ lung cancer, with a diagnosis rate of 38.6%. Its age-standardized 5-year net survival rate is relatively high at 32.9%. Despite improvements in the survival status of lung cancer in certain countries like China and Japan, the overall prognosis for lung cancer remains pessimistic. Given the current epidemiological characteristics of lung cancer, reinforcing tobacco control measures and reducing female-specific lung cancer risk factors stand as significant goals for primary prevention. Promoting low-dose computed tomography screening for high-risk population, minimizing false-positive rates in lung cancer screening, and promoting medical system reforms and standardized treatment constitute principal measures for secondary and tertiary lung cancer prevention, respectively.

Janus Membrane with Intrafibrillarly Strontium-Apatite-Mineralized Collagen for Guided Bone Regeneration

Commercial collagen membranes face difficulty in guided bone regeneration (GBR) due to the absence of hierarchical structural design, effective interface management, and diverse bioactivity. Herein, a Janus membrane called SrJM is developed that consists of a porous collagen face to enhance osteogenic function and a dense face to maintain barrier function. Specifically, biomimetic intrafibrillar mineralization of collagen with strontium apatite is realized by liquid precursors of amorphous strontium phosphate. Polycaprolactone methacryloyl is further integrated on one side of the collagen as a dense face, which endows SrJM with mechanical support and a prolonged lifespan. In vitro experiments demonstrate that the dense face of SrJM acts as a strong barrier against fibroblasts, while the porous face significantly promotes cell adhesion and osteogenic differentiation through activation of calcium-sensitive receptor/integrin/Wnt signaling pathways. Meanwhile, SrJM effectively enhances osteogenesis and angiogenesis by recruiting stem cells and modulating osteoimmune response, thus creating an ideal microenvironment for bone regeneration. In vivo studies verify that the bone defect region guided by SrJM is completely repaired by newly formed vascularized bone. Overall, the outstanding performance of SrJM supports its ongoing development as a multifunctional GBR membrane, and this study provides a versatile strategy of fabricating collagen-based biomaterials for hard tissue regeneration.

A novel and efficient electrochemiluminescence sensing strategy for the determination of trimethylamine oxide in seafood

A novel and efficient electrochemiluminescence (ECL) sensing strategy and a solid-state ECL sensor was proposed to detect trimethylamine oxide (TMAO), which is widely presented in marine species and has important physiological functions. TMAO was reduced by Fe(II)-EDTA complex to trimethylamine, acting as coreactant, to amplify the ECL response of the Ru (bpy)32+ system. To improve the detection sensitivity and efficiency, a robust solid-state ECL probe was prepared and a flow injection ECL detection system was established with a specially designed flow ECL unit, under the excitation of stepping pulse potentials. Under optimized experimental conditions, the developed ECL sensor worked well for TMAO detection in a wide linear range of 10.00 μM to 1.00 mM with a limit of detection of 3.41 μM. It was successfully applied to determine TMAO in various species of seafood samples. This work provides a promising strategy for TMAO detection.

Evaluate the value of prolonging the duration of tiopronin for injection administration in preventing hepatotoxicity

As part of supportive therapy, prophylaxis with tiopronin for injection (TI) against common hepatotoxicity complications has often been used. However, methods to prevent hepatotoxicity have not been established. Therefore, our study was aimed to find out the relationship between the periods of TI prophylaxis and post-treatment hepatotoxicity, and evaluated the value of prolonging the duration of TI administration in preventing hepatotoxicity. Hepatotoxicity was detected through liver transaminases, bilirubin, alkaline phosphatase, and clinical features of liver insufficiency. Multivariable logistic regressions were conducted to examine the association of the periods of TI prophylaxis and post-treatment hepatotoxicity. Between January 2022 and March 2023, a total of 452 patients with gynecological cancer were enrolled in the study, of which 93 (20.58%) participants were post-treatment hepatotoxicity positive. TI with different prevention days were no significant difference among participants with or without post-treatment hepatotoxicity in crude model (P > 0.05). The P-value, the odds ratios (OR) and 95% confidence intervals (CI) of participants with TI prophylaxis for 1 day for post-treatment hepatotoxicity were 0.040, 3.534 (1.061-11.765) in fully adjusted model. Past history of hepatotoxicity is a confounding variable, and there was no significant difference for post-treatment hepatotoxicity when stratified by past history of hepatotoxicity (P > 0.05). The study indicate that the periods of TI prophylaxis is not associated with post-treatment hepatotoxicity, suggesting that prolonged the periods of TI prophylaxis might be an invalid method for the prevention of post-treatment hepatotoxicity.

[Current status of global colorectal cancer prevalence, prevention and control]

Objective: This paper provides a brief overview of the epidemiology of colorectal cancer in China and around the world, and discusses how to prevent colorectal cancer to reduce its disease burden. Method: Using the official database of GLOBOCAN 2020, the China Cancer Registry Annual Report compiled by the National Cancer Center, and data from CONCORD-3.Data management was performed by Microsoft Excel 2016 and R 4.2.1 Relevant graphs were generated using the ggplot2 package for result visualization. Result: An estimated 1 931 590 people were diagnosed with colorectal cancer worldwide in 2020 with an age-standardized incidence rate of 19.5 per 100 000. There were about 935 173 deaths caused by colorectal cancer internationally, with an age-standardized mortality rate of 9.0 per 100 000. Overall, colorectal cancer was the fourth most commonly diagnosed cancer and the third leading cause of cancer-related death worldwide in 2020. In China, the age-standardized incidence rate and mortality rate of colorectal cancer was 17.3 per 100 000 and 7.8 per 100 000, respectively. Gender differences in trends were observed, with a decreasing trend in incidence and mortality among females and an increasing trend in incidence and mortality among males. The primary risk factors for colorectal cancer include age, genetic factors, gastrointestinal disorders, dietary habits, and lifestyle et al. Conclusions: Colorectal cancer poses a significant burden globally and in China. The occurrence of colorectal cancer is closely related to physiology, genetics, behavioral habits, lifestyle, and disease factors. To better control the colorectal cancer burden with the lowest cost, specific measures should be taken to reduce exposure to established risk factors. By combining the disease prevention and control strategies of tertiary prevention in China with the characteristic factors of colorectal cancer, the incidence and mortality of colorectal cancer may be effectively controlled.

Programmed release of vascular endothelial growth factor and exosome from injectable chitosan nanofibrous microsphere-based PLGA-PEG-PLGA hydrogel for enhanced bone regeneration

The healing of large bone defects remains a significant challenge in clinical practice. Accelerating both angiogenesis and osteogenesis can promote effective bone healing. In the natural healing process, angiogenesis precedes osteogenesis, providing a blood supply that supports the subsequent progression of osteogenesis. Developing a biomimetic scaffold that mimics the in vivo environment and promotes the proper sequence of vascularization followed by ossification is crucial for successful bone regeneration. In this study, a novel injectable dual-drug programmed releasing chitosan nanofibrous microsphere-based poly(D, l-lactide-co-glycolide)-b-poly(ethylene glycol)-b-poly(D,l-lactide-co-glycolide) (PLGA-PEG-PLGA) hydrogel is fabricated by incorporating vascular endothelial growth factor (VEGF) and microspheres loaded with dental pulp stem cells-derived exosomes (DPSCs-Exo). Rapid release of VEGF promotes the swift initiation of angiogenesis, while DPSCs-Exo release ensures persistent osteogenesis. Our results demonstrate that chitosan microsphere-based PLGA-PEG-PLGA hydrogel significantly promotes angiogenesis in human umbilical vascular endothelial cells and enhances the osteogenic differentiation of pre-osteoblasts. Furthermore, in vivo transplantation of this injectable chitosan microsphere-based PLGA-PEG-PLGA hydrogel into calvarial bone defects markedly promotes bone formation. Overall, our study provides a promising approach for improving bone regeneration by temporally replicating the behavior of angiogenesis and osteogenesis.

[Epidemiological characteristics and spatiotemporal distribution of schizophrenia in Ningbo, 2018-2022]

Objective: To explore the temporal and spatial distribution characteristics of reported incidence of schizophrenia in Ningbo from 2018 to 2022 and to provide a scientific basis for rational allocation of mental health resources and comprehensive prevention and treatment of schizophrenia. Methods: The reported incidence data of schizophrenia from 2018 to 2022 were collected from Ningbo's mental health information management system, and the reported incidence was calculated by township. The spatial correlation analysis and the spatiotemporal scan analysis were used to study the spatiotemporal distribution of schizophrenia. Results: The reported incidence of schizophrenia decreased from 2018 to 2022, with 4 133 new cases reported, and the annual average reported incidence was 9.76/100 000. Global and local spatial autocorrelation analysis showed positive spatial correlations and hot spots in 2018-2020. The space-time scan analysis showed an incidence cluster in Dongqiao Town, Haishu District, during 2018-2019. The RR was 2.46, and the log-likelihood ratio was 256.89. Conclusions: The reported incidence of schizophrenia in Ningbo has obvious temporal and spatial aggregation, and the high incidence area explored can provide clues for further research on the correlation between environmental factors and the incidence of schizophrenia and has certain guiding significance for the rational allocation of mental health resources in Ningbo.

Enhancing dentin bonding quality through Acetone wet-bonding technique: a promising approach

Objective: This paper aimed to assess the impact of the acetone wet-bonding (AWB) technique on dentin bonding and to investigate its potential underlying mechanisms. Materials and Methods: Caries-free third molars were sliced, ground, etched, water-rinsed. Then the specimens were randomly allocated to four groups according to the following pretreatments: 1. water wet-bonding (WWB); 2. ethanol wet-bonding (EWB); 3. 50% (v/v) acetone aqueous solution (50%AWB); 4. 100% acetone solution (AWB). Singlebond universal adhesive was then applied and composite buildups were constructed. The microtensile bond strength (MTBS), failure modes and interface nanoleakage were respectively evaluated after 24 h of water storage, 10,000 times of thermocycling or 1-month collagenase ageing. In situ zymography and contact angle were also investigated. Results: Acetone pretreatment preserved MTBS after thermocycling or collagenase ageing (p < 0.05) without affecting the immediate MTBS (p > 0.05). Furthermore, AWB group manifested fewer nanoleakage than WWB group. More importantly, the contact angle of the dentin surfaces decreased significantly and collagenolytic activities within the hybrid layer were suppressed in AWB group. Conclusion: This study suggested that the AWB technique was effective in enhancing the dentin bond durability by increasing the wettability of dentin surface to dental adhesives, removing residual water in the hybrid layer, improving the penetration of adhesive monomer, and inhibiting the collagenolytic activities. Clinical significance: The lifespan of adhesive restorations would be increased by utilization of acetone wet-bonding technique.

Risk factors for postoperative infections in esophageal tumor patients

Postoperative infections (PI) are a serious complication after esophageal cancer surgery, as they might be correlated with an elevated risk of death. While several reports discuss risk factors for PI in esophageal tumor surgery, there is a limited amount of research on overall postoperative infections. Therefore, investigating the factors that influence PI holds great clinical significance. We retrospectively reviewed surgical data from a cohort of 902 patients diagnosed with esophageal tumors. The study included esophageal cancer patients treated in the Department of Thoracic Surgery at Anyang Tumor Hospital from January to December 2021. Preoperative and operative risk factors for PI were evaluated using univariable and multivariable analyses. The overall incidence of PI was 28.3% (255/902). Multivariable logistic regression analysis revealed that smoking and preoperative hospital stays are significant risk factors for PI after esophageal tumor surgery. Smoking and preoperative hospital stays are identified as risk factors for PI following esophageal tumor surgery. Based on our results, we predict that certain groups of patients may have a higher risk of PI following esophageal tumor surgery. Preventive measures or closely monitor of these patients may be required to reduce the incidence of postoperative PI.

Corrigendum to "Epigallocatechin-3-gallate/mineralization precursors co-delivery hollow mesoporous nanosystem for synergistic manipulation of dentin exposure" [Bioact. Mater. 23 (2023) 394-408]

[This corrects the article DOI: 10.1016/j.bioactmat.2022.11.018.].

Epigallocatechin-3-gallate/mineralization precursors co-delivery hollow mesoporous nanosystem for synergistic manipulation of dentin exposure

As a global public health focus, oral health plays a vital role in facilitating overall health. Defected teeth characterized by exposure of dentin generally increase the risk of aggravating oral diseases. The exposed dentinal tubules provide channels for irritants and bacterial invasion, leading to dentin hypersensitivity and even pulp inflammation. Cariogenic bacterial adhesion and biofilm formation on dentin are responsible for tooth demineralization and caries. It remains a clinical challenge to achieve the integration of tubule occlusion, collagen mineralization, and antibiofilm functions for managing exposed dentin. To address this issue, an epigallocatechin-3-gallate (EGCG) and poly(allylamine)-stabilized amorphous calcium phosphate (PAH-ACP) co-delivery hollow mesoporous silica (HMS) nanosystem (E/PA@HMS) was herein developed. The application of E/PA@HMS effectively occluded the dentinal tubules with acid- and abrasion-resistant stability and inhibited the biofilm formation of Streptococcus mutans. Intrafibrillar mineralization of collagen fibrils and remineralization of demineralized dentin were induced by E/PA@HMS. The odontogenic differentiation and mineralization of dental pulp cells with high biocompatibility were also promoted. Animal experiments showed that E/PA@HMS durably sealed the tubules and inhibited biofilm growth up to 14 days. Thus, the development of the E/PA@HMS nanosystem provides promising benefits for protecting exposed dentin through the coordinated manipulation of dentin caries and hypersensitivity.

Three-dimensionally printed implant surgical guide-related experience, knowledge, attitude, and professional behaviors among 2028 dentists in China: A cross-sectional study

STATEMENT OF PROBLEM

Research on the current place of 3-dimensionally printed implant surgical guides (3D-ISGs) among practicing dentists worldwide is lacking, with little research focused on dentists' experience, knowledge, attitude, or professional behavior related to 3D-ISG or on the main obstacle to adoption.

PURPOSE

The purpose of this cross-sectional study was to identify the adoption of 3D-ISG in dental practice in China and to determine factors that influence its further application and dentists' attitudes and willingness.

MATERIAL AND METHODS

Semistructured questionnaires were sent to a sample of Chinese dentists composed of users and nonusers of 3D-ISG. The questionnaires were displayed and distributed through a professional online survey system (http://www.wjx.cn) and a social media platform (WeChat). The responses were analyzed with multivariable generalized equations, and the effect of various demographic variables was determined, including dentist experience, academic degree, and type of practice (public or private).

RESULTS

A total of 2028 valid questionnaires were collected. In dental practice, 39.3% of the respondents used 3D-ISG. Respondents with a PhD (62.4%) used the 3D-ISG more than twice as frequently as respondents with a junior college degree or below (31.8%). The majority of the members of implantology departments (81.7%) applied 3D-ISG, but doctors in other departments used it at a rate of less than half. The 3D-ISG was most frequently used in the maxillary anterior area (78.4%), followed by the edentulous maxilla and mandible (61.0% and 60.5%, respectively). The main barriers were high initial cost, complex and time-consuming digital design, and lack of expertise in the proper use of 3D-ISG.

CONCLUSIONS

Most dentists did not use 3D-ISG in dental practice. The 3D-ISG application rate was significantly associated with sex, academic degree, years of dental practice, department, monthly income, and type of healthcare facility. To improve the popularity of 3D-ISG, particularly among dentists without advanced degrees, it would be important to optimize the digital design software program and provide sufficient training.

Fabrication of an exosome-loaded thermosensitive chitin-based hydrogel for dental pulp regeneration

Injective thermosensitive hydrogels are considered promising scaffolds to trigger dental pulp regeneration in devitalized human teeth. In this study, we developed a hydroxypropyl chitin (HPCH)/chitin whisker (CW) thermosensitive hydrogel with enhanced mechanical properties and biological activities. Exosomes can serve as biomimetic tools for tissue engineering, but the rapid clearance of unconjugated exosomes in vivo limits their therapeutic effects. To address this challenge, exosomes were isolated from human pulp stem cells (hDPSCs) and directly embedded into the HPCH/CW pre-gel to form an exosome-loaded hydrogel (HPCH/CW/Exo). The exosome-loaded thermosensitive hydrogel can be easily injected into an irregular endodontic space and gelated in situ. In vitro cell experiments proved that the delivery of exosomes significantly improved the ability of hydrogels to promote odontogenesis and angiogenesis. Meanwhile, in vivo animal experiments revealed the formation of new dental pulp-like tissues in an implanted tooth root model. Therefore, the proposed hydrogel provides a great potential alternative to traditional root canal therapy in dental clinics.

Evaluating how lodging affects maize yield estimation based on UAV observations

Timely and accurate pre-harvest estimates of maize yield are vital for agricultural management. Although many remote sensing approaches have been developed to estimate maize yields, few have been tested under lodging conditions. Thus, the feasibility of existing approaches under lodging conditions and the influence of lodging on maize yield estimates both remain unclear. To address this situation, this study develops a lodging index to quantify the degree of lodging. The index is based on RGB and multispectral images obtained from a low-altitude unmanned aerial vehicle and proves to be an important predictor variable in a random forest regression (RFR) model for accurately estimating maize yield after lodging. The results show that (1) the lodging index accurately describes the degree of lodging of each maize plot, (2) the yield-estimation model that incorporates the lodging index provides slightly more accurate yield estimates than without the lodging index at three important growth stages of maize (tasseling, milking, denting), and (3) the RFR model with lodging index applied at the denting (R5) stage yields the best performance of the three growth stages, with R² = 0.859, a root mean square error (RMSE) of 1086.412 kg/ha, and a relative RMSE of 13.1%. This study thus provides valuable insight into the precise estimation of crop yield and demonstra\tes that incorporating a lodging stress-related variable into the model leads to accurate and robust estimates of crop grain yield.

Extrafibrillarly Demineralized Dentin Matrix for Bone Regeneration

Dentin is a natural extracellular matrix, but its availability in bone grafting and tissue engineering applications is underestimated due to a lack of proper treatment. In this study, the concept of extrafibrillar demineralization is introduced into the construction of dentin-derived biomaterials for bone regeneration for the first time. Calcium chelating agents with large molecular weights are used to selectively remove the extrafibrillar apatite minerals without disturbing the intrafibrillar minerals within dentin collagen, resulting in the formation of an extrafibrillarly demineralized dentin matrix (EDM). EDM with distinctive nanotopography and bone-like mechanical properties is found to significantly promote cell adhesion, migration, and osteogenic differentiation in vitro while enhancing in vivo bone healing of rat calvarial defects. The outstanding osteogenic performance of EDM is further confirmed to be related to the activation of the focal adhesion-cytoskeleton-nucleus mechanotransduction axis. Overall, this study shows that extrafibrillar demineralization of dentin has great potential to produce hierarchical collagen-based scaffolds for bone regeneration, and this facile top-down fabrication method brings about new ideas for the biomedical application of naturally derived bioactive materials.

[Epidemiological investigation on the local epidemic situation in Zhengzhou High-Tech Zone caused by SARS-CoV-2 Delta variant]

This study collected epidemic data of COVID-19 in Zhengzhou from January 1 to January 20 in 2022. The epidemiological characteristics of the local epidemic in Zhengzhou High-tech Zone caused by the SARS-CoV-2 Delta variant were analyzed through epidemiological survey and big data analysis, which could provide a scientific basis for the prevention and control of the Delta variant. In detail, a total of 276 close contacts and 599 secondary close contacts were found in this study. The attack rate of close contacts and secondary close contacts was 5.43% (15/276) and 0.17% (1/599), respectively. There were 10 confirmed cases associated with the chain of transmission. Among them, the attack rates in close contacts of the first, second, third, fourth and fifth generation cases were 20.00% (5/25), 17.86% (5/28), 0.72% (1/139) and 14.81% (4/27), 0 (0/57), respectively. The attack rates in close contacts after sharing rooms/beds, having meals, having neighbor contacts, sharing vehicles with the patients, having same space contacts, and having work contacts were 26.67%, 9.10%, 8.33%, 4.55%, 1.43%, and 0 respectively. Collectively, the local epidemic situation in Zhengzhou High-tech Zone has an obvious family cluster. Prevention and control work should focus on decreasing family clusters of cases and community transmission.

Biomineralization-inspired sandwich dentin desensitization strategy based on multifunctional nanocomposite with yolk-shell structure

Dentin hypersensitivity (DH) treatment is far from being unequivocal in providing a superior strategy that combines immediate and long-term efficiency of dentinal tubule (DT) occlusion and clinical applicability. In order to achieve this aim, a type of multifunctional yolk-shell nanocomposite with acid resistance, mechanical resistance and biomineralization properties was developed in this study, which consists of a silica/mesoporous titanium-zirconium nanocarrier (STZ) and poly(allylamine hydrochloride) (PAH)-stabilized amorphous calcium phosphate (ACP) liquid precursor. First, the nanocomposite, named as PSTZ, immediately occluded DTs and demonstrated outstanding acid and mechanical resistance. Second, the PSTZ nanocomposite induced intrafibrillar mineralization of single-layer collagen fibrils and remineralization of demineralized dentin matrix. Finally, PSTZ promoted the odontogenic differentiation of dental pulp stem cells by releasing ACP and silicon ions. The reconstruction of the dentin-mimicking hierarchical structure and the introduction of newly formed minerals in the upper, middle and lower segments of DTs, defined as sandwich-like structures, markedly reduced the permeability and achieved superior long-term sealing effects. The nanocomposite material based on mesoporous yolk-shell carriers and liquid-phase mineralized precursors developed in this study represents a versatile biomimetic sandwich desensitization strategy and offers fresh insight into the clinical management of DH.

Enhancing adhesive-dentin interface stability of primary teeth: From ethanol wet-bonding to plant-derived polyphenol application

OBJECTIVES

To investigate whether the adhesive-dentin interface stability of primary teeth would be enhanced by epigallocatechin-3-gallate (EGCG) with ethanol wet-bonding.

METHODS

Non-caries primary molars were sliced to achieve a flat dentin surface and etched then randomly distributed into five groups in accordance with different treatments: group 1, no treatment; group 2, applying absolute ethanol wet-bonding for 60 s; groups 3-5, applying 0.1%, 0.5%, and 1% (w/v) EGCG-incorporating ethanol wet-bonding (0.1%, 0.5%, and 1% EGCG) for 60 s. Singlebond universal adhesive was then applied followed by resin composite construction. Microtensile bond strength, fracture mode, and nanoleakage at adhesive-dentin interface were evaluated after 24 h of water storage or 10,000 times of thermocycling. Zymography of hybrid layer, biofilm formation of Streptococcus mutans by CLSM, FESEM, and MTT test, and cytotoxicity by CCK-8 assay were respectively assessed.

RESULTS

Irrespective of thermocycling, the dentin bond strength was preserved with reduced nanoleakage in the 0.5% and 1% EGCG groups. Furthermore, the activity of endogenous proteases and the growth of Streptococcus mutans biofilm were inhibited after treatment with 0.5% and 1% EGCG/ethanol solutions (groups 4 and 5). CCK-8 results of the 0.1% and 0.5% EGCG groups showed acceptable biocompatibility.

CONCLUSIONS

Treatment by EGCG/ethanol solutions effectively enhanced the bond stability of primary teeth at the adhesive-dentin interface.

CLINICAL SIGNIFICANCE

Synergistic application of EGCG and ethanol wet-bonding suggesting a promising strategy to improve dentin bonding durability with bacterial biofilm inhibition, thus increasing resin-based restorations' service life in primary dentition.

Multifunctional modification of orthodontic adhesives with ZnO quantum dots

OBJECTIVES

To develop a multifunctional orthodontic adhesive (QDA) using ZnO quantum-dots (ZnQDs) as modifier and investigate the antibacterial capability, fluorescence property as well as biocompatibility and bonding property.

METHODS

ZnQDs were synthesized using sol-gel method. XPS, XRD, FT-IR, HRTEM, SAED, DLS and spectrofluorimetry were used to characterize ZnQDs. ZnQDs were incorporated into Transbond XT adhesive paste with 20 %, 30 %, 40 % mass fraction, respectively, to form the multifunctional adhesives (QDAs). Antibacterial capability was evaluated with MTT kit, CFU count and Live/Dead Bacterial Staining Kit. Ultraviolet photography and spectrofluorimetry were used to confirm the fluorescence property of QDAs. Biocompatibility assay was performed on gingival fibroblasts and subcutaneous tissue of rats. Softening in solvent rate, shear bond strength and degree of conversion (DC) were measured.

RESULTS

The synthesized ZnQDs presented excellent crystallinity and fluorescence properties. MTT assay, CFU count and CLSM analysis indicated that QDAs had significant antibacterial activity compared with Transbond XT adhesive paste. CCK-8 assay and Live/Dead cell staining analysis denied the cytotoxicity of QDAs and histological analysis proved that QDAs all had no inflammatory irritation to subcutaneous tissue. Softening in solvent, shear bond strength and DC evaluations indicated that 20 % mixing ratio of ZnQDs could enhance the resistance to degradation without influencing the bond strength and DC. Ultraviolet photography and spectrofluorimetry analysis proved the fluorescence capability of QDAs.

SIGNIFICANCE

ZnQDs can impart antibacterial and fluorescence properties to orthodontic adhesives without affecting biocompatibility and bonding performance. QDAs can be multifunctional orthodontic adhesives to reduce bacterial adhesion around brackets and help orthodontists remove residual adhesives precisely when needed.

Application of Amorphous Calcium Phosphate Agents in the Prevention and Treatment of Enamel Demineralization

Enamel demineralization, as a type of frequently-occurring dental problem that affects both the health and aesthetics of patients, is a concern for both dental professionals and patients. The main chemical composition of the enamel, hydroxyapatite, is easy to be dissolved under acid attack, resulting in the occurrence of enamel demineralization. Among agents for the preventing or treatment of enamel demineralization, amorphous calcium phosphate (ACP) has gradually become a focus of research. Based on the nonclassical crystallization theory, ACP can induce the formation of enamel-like hydroxyapatite and thereby achieve enamel remineralization. However, ACP has poor stability and tends to turn into hydroxyapatite in an aqueous solution resulting in the loss of remineralization ability. Therefore, ACP needs to be stabilized in an amorphous state before application. Herein, ACP stabilizers, including amelogenin and its analogs, casein phosphopeptides, polymers like chitosan derivatives, carboxymethylated PAMAM and polyelectrolytes, together with their mechanisms for stabilizing ACP are briefly reviewed. Scientific evidence supporting the remineralization ability of these ACP agents are introduced. Limitations of existing research and further prospects of ACP agents for clinical translation are also discussed.

[Perioperative management and complication control of Le Fort Ⅲ osteotomy in children with syndromic craniosynostosis]

Objective: To summarize the preliminary efficacy, perioperative management and complications of Le Fort Ⅲ osteotomy and midface distraction in patients with syndromic craniosynostosis by retrospective analysis, and to provide clinical experience for reference. Methods: From October 2017 to January 2020, 20 patients with syndromic craniosynostosis underwent Le Fort Ⅲ osteotomy and distraction in The Department of Oral and Maxillofacial Surgery of Peking University International Hospital, including 11 males and 9 females, were involved. The median age was 7 years (1.5 to 15 years). Preoperative risk prevention plan was put forward by multidisciplinary evaluation, and preoperative intervention was carried out. The diagnostic data of SNA, airway volume, polysomnography (PSG), ophthalmology and occlusal relationship were obtained through specialized examination, and osteotomy and distraction surgical plan was formulated through virtual surgical planning. CT was taken 1 week and 3, 6, 12 months after operation, PSG and eye protrudence examination were conducted to evaluate the therapeutic effect, syndrome type, multiple disciplinary treatment (MDT) intervention, occurrence and outcome of complications were summarized. Results: There were 15 cases of Crouzon syndrome and 5 cases of Pfeiffer syndrome. Sleep apnea was the first complaint in 18 cases and exophthalmia in 2 cases. Preoperative interventional therapy included 4 cases of adenoid surgery, 2 cases of continuous positive airway pressure and 2 cases of maxillary expansion. The most common surgical complications were accidental fracture (14/20 cases, 70%), cerebrospinal fluid fistula (2 cases), internal carotid cavernous sinus fistula (1 case), postoperative hyponatraemia (5 cases), crying syndrome (2 cases), wound infection (2 cases), trichiasis of lower eyelid (4 cases), and nasal malformation (1 case). Three cases underwent unplanned secondary surgery. SNA, airway volume and mean percutaneous arterial oxygen saturation (SpO₂) six months after operation were significantly higher than those before operation (F=10.09, P=0.001; F=5.13, P<0.001; F=10.78, P=0.001), and the protrusion and apnea hypopnea index were significantly lower than those before surgery (F=6.73, P=0.010; F=18.47, P<0.001). There were no significant differences in SNA, airway volume, mean SpO₂, ophthalmology between 6 months after surgery and 1 year after surgery (P>0.05). Conclusions: Perioperative safety assessment and early intervention of MDT is an effective diagnosis and treatment model of Le Fort Ⅲ osteotomy and distraction for syndromic craniosynosis. The operative complications are mainly local, and systemic complications are controllable.

Effects of Plant Extracts on Dentin Bonding Strength: A Systematic Review and Meta-Analysis

Objective: To systematically review in vitro studies that evaluated the effects of plant extracts on dentin bonding strength.

Materials and Methods: Six electronic databases (PubMed, Embase, VIP, CNKI, Wanfang and The Cochrane Library) were searched from inception to September 2021 in accordance with the Preferred Reporting Items for Systematic Reviews (PRISMA). In vitro studies that compared the performance of dental adhesives with and without the plant extracts participation were included. The reference lists of the included studies were manually searched. Two researchers carried out study screening, data extraction and risk of bias assessment, independently and in duplicate. Meta-analysis was conducted using Review Manager 5.3.

Results: A total of 62 studies were selected for full-text analysis. 25 articles used the plant extracts as primers, while five added the plant extracts into adhesives. The meta-analysis included 14 articles of in vitro studies investigating the effects of different plant extract primers on dentin bonding strength of etch-and-rinse and self-etch adhesives, respectively. The global analysis showed statistically significant difference between dental adhesives with and without plant extract primers. It showed that the immediate bond strength of dental adhesives was improved with the application of plant extract primers.

Conclusion: The application of proanthocyanidin (PA) primers have positive effect on the in vitro immediate bonding strength of dental adhesives irrespective of etch-and-rinse or self-etch modes.

Solvent Mediating the in Situ Self-Assembly of Polysaccharides for 3D Printing Biomimetic Tissue Scaffolds

Intensively studied 3D printing technology is frequently hindered by the effective printable ink preparation method. Herein, we propose an elegant and gentle solvent consumption strategy to slowly disrupt the thermodynamic stability of the biopolymer (polysaccharide: cellulose, chitin, and chitosan) solution to slightly induce the molecule chains to in situ self-assemble into nanostructures for regulating the rheological properties, eventually achieving the acceptable printability. The polysaccharides are dissolved in the alkali/urea solvent. The weak Lewis acid fumed silica (as solvent mediator) is used to (i) slowly and partially consume the alkali/urea solvent to induce the polysaccharide chains to self-assemble into nanofibers to form a percolating network in a limited scale without leading to gelation and (ii) act as the support to increase the solution modulus, for achieving superior printability and scaffold design flexibility. As a demonstration, the resulting polysaccharide scaffolds with biomimetic nanofibrous structures exhibit superior performances in both the cell-free and cell-loaded bone tissue engineering strategies, showing the potential in tissue engineering. Moreover, the fumed silica could be completely removed by alkali treatment without defecting the nanofibrous structure, showing the potential in various applications. We anticipate our solvent-mediated 3D printing ink preparation concept could be used to fabricate other polymeric facile inks and for widespread applications in diverse fields.

Evaluation of resveratrol-doped adhesive with advanced dentin bond durability

OBJECTIVES

This paper aimed to evaluate the influence of resveratrol-doped adhesive on the durability and antibiofilm capability of dentin bonding.

METHODS

Experimental adhesives were prepared by incorporating resveratrol into a universal adhesive at concentrations of 0 (control), 0.1, 1, and 10 mg/mL. The microtensile bond strength, fracture modes, and adhesive-dentin interface nanoleakage were assessed after 24 h of water storage, 10,000 times of thermocycling or 1-month of collagenase ageing. Relevant antibiofilm capability on Streptococcus mutans (S. mutans), in situ zymography, degree of conversion, and cytotoxicity of resveratrol-doped adhesives were also determined.

RESULTS

Irrespective of thermocycled or collagenase ageing, the resveratrol-doped adhesive (1 mg/mL) maintained the bond strength and reduced the nanoleakage expression. Meanwhile, the inhibitory ability on endogenous protease activity and S. mutans biofilm formation with acceptable biocompatibility were obtained.

CONCLUSIONS

This study suggested that the resveratrol-doped adhesive achieved effective improvement on dentin bond durability and secondary caries management.

CLINICAL SIGNIFICANCE

The application of the resveratrol-doped adhesive indicates promising benefits to increase the lifetime of composite restorations.

Effect of aging on color stability and bond strength of dual-cured resin cement with amine or amine-free self-initiators

This study aimed to evaluate the effect of aging on the color stability and bond strengths of dual-cured resin cements containing amine or amine-free self-initiators. Three dual-cured and one light-cured resin cements were used. The covered (by lithium disilicate ceramic disks) and uncovered groups (n=10) were included. Color measurements were tested after 24 h, 10,000 and 20,000 thermal cycles (TCs). Micro-shear bond strengths (µSBS) were tested after 24 h, 10,000 and 20,000 TCs, and failure modes were analyzed (n=14). Two-way ANOVA and Tukey's test were implemented for color difference (ΔE*_ab) and µSBS (α=0.05). The mean ΔE*_ab difference was significant among groups (p<0.001). The lowest ΔE*_ab values were obtained for dual-cured resin cement with amine-free self-initiators dual-cured cement after aging in all dual-cured resin cements, and the µSBS of the dual-cured resin cements on ceramic was significantly higher than that of the light-cured ones after aging (p<0.001).

An MSN-based synergistic nanoplatform for root canal biofilm eradication via Fenton-enhanced sonodynamic therapy

The validity and biocompatibility of irrigating agents are imperative for the success of root canal therapy. The imperfections in the currently available irrigants highlight the fact that more advanced technologies and strategies are required for complete disinfection in endodontic treatments. In the present study, a Fenton reaction-enhanced antimicrobial sonodynamic therapy (SDT) platform was fabricated for root canal disinfection. Firstly, mesoporous silica nanoparticles (MSNs) were synthesized, grafted with an amino group and then conjugated with sonosensitizer protoporphyrin IX (PpIX). Iron ions were then anchored (M@P-Fe) to initiate a Fenton reaction. Nanoparticle characterization by size and zeta potential measurements, scanning electron microscopy, transmission electron microscopy and thermogravimetric analysis confirmed that the platform was successfully developed. Reactive oxygen species (ROS) generation assessment, methylene blue degradation and electron spin resonance assays illustrated upon ultrasound (US) irradiation, that augmented ROS, can be produced by US activated PpIX and iron mediated Fenton reactions from low concentration H2O2 (0.01%). In vitro anti-Enterococcus faecalis efficacy was demonstrated by growth curve and colony forming unit measurements. Confocal laser scanning microscopy and scanning electron microscopy observations illustrated the effectiveness of the platform on in situ biofilm eradication in root canal. Owing to the stronger oxidizing capability and short lifetime of ROS, the Fenton reaction-enhanced SDT can induce detrimental oxidative damage to bacteria upon activation of US while avoiding nonspecific toxicity to cells, which was verified by cytotoxicity evaluations using CCK-8 assay and morphology observation of MC3T3-E1 cells. Compared to commonly used NaClO, this nanoplatform displayed desirable anti-bacterial, anti-biofilm abilities and better biocompatibility. These results highlight that the integrated M@P-Fe + US + H2O2 platform is a promising candidate for US enhanced root canal irrigation and disinfection.

[Influence of female age on the fresh cycle live birth rate of different controlled ovarian hyperstimulation protocols in poor ovarian response patients]

Objective: To investigate the influence of age on the fresh cycle live birth rate in patients with poor ovarian response in different controlled ovarian hyperstimulation groups. Methods: The clinical data of 3 342 patients in The First Affiliated Hospital of Zhengzhou University from February 2014 to November 2018 were retrospectively collected, including early-follicular phase long-acting gonadotropin-releasing hormone (GnRH) agonist long protocol group (1 375 cases), mid-luteal phase short-acting GnRH agonist long protocol group (1 161 cases) and GnRH antagonist protocol group (806 cases); each group was divided into 4 subgroups according to age: ≤30 years, 31－35 years, 36－40 years and >40 years, the pregnancy outcomes in each age subgroup were analyzed under different controlled ovarian hyperstimulation protocols. Results: In early-follicular phase long-acting GnRH agonist long protocol group, the final live birth rates of each age subgroup were 39.4% (228/579), 36.1% (135/374), 16.6% (48/290) and 3.0% (4/132); in mid-luteal phase short-acting GnRH agonist long protocol group, live birth rates of each age subgroup were 32.1% (99/308), 20.8% (55/264), 13.0% (45/346) and 7.0% (17/243); in GnRH antagonist protocol group, live birth rates of each age subgroup were 22.8% (26/114), 16.3% (25/153), 11.2% (31/278), and 3.8% (10/261); the live birth rate of each group decreased significantly with the increase of age (all P<0.01). When the age≤35 years old, the fresh cycle live birth rate of the early-follicular phase long-acting GnRH agonist long protocol group was significantly better than those of the other two groups (all P<0.01). The multivariate logistic regression analysis of age and live birth rate of the three controlled ovarian hyperstimulation groups showed age was the independent influence factor (OR=0.898, 95%CI: 0.873-0.916, P<0.01; OR=0.926, 95%CI: 0.890-0.996, P<0.01; OR=0.901, 95%CI: 0.863-0.960, P<0.01). Conclusions: Age is an independent influencing factor for the prediction of fresh cycle live birth rate in low ovarian response patients. No matter which controlled ovarian hyperstimulation protocol is adopted, the final live birth rate decreases significantly with the increase of women's age. In addition, the early-follicular phase long-acting GnRH agonist long protocol has the highest fresh cycle live birth rate among all controlled ovarian hyperstimulation groups.

In vitro evaluation of the anti-proteolytic and cross-linking effect of mussel-inspired monomer on the demineralized dentin matrix

OBJECTIVES

To evaluate the anti-proteolytic and cross-linking effect of N-(3,4-dihydroxyphenethyl)methacrylamide (DMA) on the demineralized dentin matrix in vitro.

METHODS

Four experimental solutions were selected: 50% ethanol/water solution (Control); 1, 5, and 10 mmol/L DMA dissolved in 50% ethanol/water solution. Sound human molars were sectioned to produce dentin beams with dimension of 1×1×6 mm. The dentin beams were demineralized with 10% phosphoric acid for 8 h to remove the apatite. The demineralized specimens were randomly separated into four groups and immersed in the four experimental solutions for 1 h. After the treatment, the ultimate tensile strength (UTS), loss of dry mass and the release of hydroxyproline by storing the treated specimens in 0.1 mg/mL collagenase solution for 24 h were assessed. The swelling ratio of another ten specimens from each group were evaluated. The interaction between DMA with dentin matrix was observed under Field Emission Scanning Electron Microscopy (FESEM). UTS data was analyzed by two-way ANOVA followed by Tukey test, and the other data was analyzed by one-way ANOVA followed by Tukey test (α = 0.05).

RESULTS

The two-way ANOVA factors, different solutions (p < 0.001), collagenase degradation (p < 0.001) and their interactions (p < 0.001) all significantly affected the UTS. The 10 mM DMA treatment significantly decreased the percentage of loss of dry mass, release of hydroxyproline and swelling ratio of demineralized dentin matrix compared to other treatment groups (p < 0.05). The FESEM observation depicted that with increasing concentration of DMA, the structure of dentin matrix was protected and the porosity within dentin collagen network was decreased.

CONCLUSIONS

The treatment by 10 mM DMA/ethanol solution for 1 hour is capable of enhancing the mechanical properties of demineralized dentin matrix against collagenase degradation and may be clinically useful to improve the durability of hybrid layer.

CLINICAL SIGNIFICANCE

The 10 mM DMA/ethanol primer may offer an alternative choice for dentists to strengthen the mechanical properties of demineralized dentin matrix and resist its degradation by collagenase.

[Analysis on monitoring results of individual dose of occupational external radiation among radiation workers in Lanzhou in 2019]

Objective: To analyze the individual dose level of occupational external radiation of radiation workers in Lanzhou in 2019, so as to provide reference for radiation protection and occupational health management. Methods: In April 2020, a total of 1460 radiation workers in Gansu Provincial Center for Disease Control and Prevention in 2019 were selected as the research objects. The unit nature, hospital level and occupational category of the monitored workers were collected, and the monitoring results of external radiation personal dose in 2019 were analyzed and compared. Results: In the occupational external radiation monitoring of radiation workers in Lanzhou in 2019, the effective dose of 48 persons was 1.0~<5.0 mSv, the effective dose of 2 persons was 5.0~<10.0 mSv, the annual collective effective dose was 308.21 people·mSv, and the average annual effective dose of monitored persons was 0.21 mSv/a. There was significant difference in the distribution of annual effective dose per capita among different occupational groups (H=34.43, P<0.05) . The annual effective dose per capita of nuclear medicine personnel was higher (0.56 mSv/a) , followed by interventional radiology (0.33 mSv/a) . The ratio of annual collective dose to total annual collective dose with annual individual dose more than 5 mSv (SR(5)) and the ratio of the number of staff with annual individual dose more than 1mSv to the total number of monitored personnel (NR(1)) were higher in nuclear medicine and interventional radiology personnel. The average annual effective dose distribution of diagnostic radiologists in different level hospitals was statistically significant (H=16.46, P<0.05) . The average annual effective dose in private hospitals, community hospitals and health centers was higher (0.32 mSv) , followed by county hospitals (0.23 mSv) . Conclusion: The individual dose of occupational external radiation of radiation workers in Lanzhou is generally low, and the annual effective dose of nuclear medicine and interventional radiology workers is high. The management of radiation protection should be emphasis on this people. And it is suggested to strengthen the supervision of private hospitals and update and maintain the equipment of community health centers.

The Stability of Dentin Surface Biobarrier Consisting of Mesoporous Delivery System on Dentinal Tubule Occlusion and Streptococcus Mutans Biofilm Inhibition

Background

The dentin exposure always leads to dentin hypersensitivity and/or caries. Given the dentin’s tubular structure and low mineralization degree, reestablishing an effective biobarrier to stably protect dentin remains significantly challenging. This study reports a versatile dentin surface biobarrier consisting of a mesoporous silica-based epigallocatechin-3-gallate (EGCG)/nanohydroxyapatite delivery system and evaluates its stability on the dentinal tubule occlusion and the Streptococcus mutans (S. mutans) biofilm inhibition.

Materials and Methods

The mesoporous delivery system was fabricated and characterized. Sensitive dentin discs were prepared and randomly allocated to three groups: 1, control group; 2, casein phosphopeptide–amorphous calcium phosphate (CPP–ACP) group; and 3, the mesoporous delivery system group. The dentin permeability, dentinal tubule occlusion, acid and abrasion resistance, and S. mutans biofilm inhibition were determined for 1 week and 1 month. The in vitro release profiles of EGCG, Ca, and P were also monitored.

Results

The mesoporous delivery system held the ability to sustainably release EGCG, Ca, and P and could persistently occlude dentinal tubules with acid and abrasion resistance, reduce the dentin permeability, and inhibit the S. mutans biofilm formation for up to 1 month compared with the two other groups. The system provided prolonged stability to combat oral adverse challenges and served as an effective surface biobarrier to protect the exposed dentin.

Conclusion

The establishment of the dentin surface biobarrier consisting of a mesoporous delivery system indicates a promising strategy for the prevention and the management of dentin hypersensitivity and caries after enamel loss.

Effect of universal adhesive and silane pretreatment on bond durability of metal brackets to dental glass ceramics

This study aimed to investigate the effect of universal adhesive and silane pretreatment on the bond durability of metal brackets to dental glass ceramics. Eighty lithium disilicate glass ceramic specimens were randomly assigned to one of four groups (n = 20) defined by the pretreatment and adhesive used: (i) Adper Single Bond 2; (ii) silane + Adper Single Bond 2; (iii) Single Bond Universal; and (iv) silane +Single Bond Universal. Maxillary central incisor metal brackets were bonded on the ceramic surfaces with resin composite. A shear bond strength test was conducted after 24 h of water storage and after 10,000 thermocycles. Adhesive remnant index scoring and field-emission scanning electron microscopy were performed to determine adhesives remaining on the ceramic surfaces and the ceramic ultrastructure following bracket debonding, respectively. After 10,000 thermocycles, specimens treated with Single Bond Universal preserved an appropriate bond strength between brackets and glass ceramics and showed minimum ceramic surface damage following bracket debonding, which was not the case in the other three groups. The application of a silane-containing universal adhesive without silane pretreatment achieves adequate durability of the bond of metal brackets to dental glass ceramics and allows safe debonding, which may aid in optimizing the effectiveness for orthodontic treatment.

[Research progress of liposome drug delivery system in stomatology]

Liposomes are spherical vesicles with bilayer membrane structure spontaneously formed by phospholipids dispersed in an aqueous medium. Liposomes are excellent drug carrier with amphiphilic properties. Liposomes have good biocompatibility, biodegradability and no immunogenicity. Liposomes can achieve the delivery of the drug, enhance the solubility, improve the stability, reduce the toxic effect of the drug, and improve the therapeutic effect of the loaded drug. In recent years, liposome drug delivery systems have been widely used in dentistry. This article reviews the application of liposome drug delivery systems in caries, dental pulp diseases, periodontitis, implantation, oral anesthesia and oral candidiasis.

Effects of Desensitizers on Adhesive-Dentin Bond Strength: A Systematic Review and Meta-analysis

Purpose

To systematically review in vitro studies that evaluated adhesive-dentin bond strength with or without the addition of desensitizers.

Materials and Methods

A search was conducted in four databases (PubMed, Embase, Web of Science, and Cochrane Library) without publication date or language limits in accordance with the Preferred Reporting Items for Systematic Reviews (PRISMA). Two reviewers selected the studies, extracted data, and assessed the risk of bias independently. The inclusion criterion was the evaluation of the effect of immediate or aged bond strength after applying desensitizer in the bonding step. The risk of bias was assessed following the method used by Sarkis-Onofre et al.41 Meta-analysis was conducted using Review Manager 5.3.

Results

A total of 1636 articles were found using the search strategy above; 59 articles were selected for full-text analysis, and 32 were systematically reviewed, with 18 considered in the meta-analysis. Results showed a significant difference among various kinds of desensitizers. The subgroup comparison showed high heterogeneity among the different kinds of desensitizers. The use of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and arginine-CaCO3 showed no negative effect on the immediate bond strength, whereas other desensitizers showed some influence.

Conclusion

Different desensitizers have various effects on microtensile bond strength. Desensitizers may be selected based on the bond strength and especially used to relieve tooth sensitivity after tooth preparation.

[The effect of endocapillary hypercellularity lesions on the renal prognosis and response to immunosuppressive therapy in IgA nephropathy]

In this retrospective cohort study, we aim to evaluate the effect of endocapillary hypercellularity (E) lesions on the renal prognosis and response to immunosuppressive therapy, especially diffuse endocapillary hypercellularity lesion in IgA nephropathy (IgAN). A total of 365 patients with IgAN and E lesions and 31 patients with diffuse E lesions and over 12-month follow-up period were included in this study. We performed an 1∶1 propensity score to identify controls with matched clinical and pathological features from 769 IgAN patients without E lesions. The end-point was defined as a 30% decrease in estimated glomerular filtration rate (eGFR) or end-stage kidney disease. The kidney survival of the two groups was compared by Kaplan-Meier analysis. During median follow-up period of 41 months, kidney survival rates in patients with E lesions were 96.0% at 1 year, 83.6% at 3 years, 67.7% at 5 years; while they were 96.9% at 1 year, 83.6% at 3 years, and 68.7% at 5 years in patients without E lesions (P=0.265).The HR of immunosuppressive therapy was 1.038 (95%CI 0.749-1.440) and 1.113 (95%CI 0.770-1.609) in patients not receiving immunosuppressive therapy (P=0.781). (2) During median follow-up period of 52.5 months, the kidney survival rates in patients with diffuse E-lesion were 100.0% at 1 year, 96.2% at 3 years, 74.5% at 5 years; while they were 96.2% at 1 year, 82.3% at 3 years, and 63.7% at 5 years in patients without E-lesion (P=0.158). The HR of immunosuppressive therapy was 0.625 (95%CI 0.213-1.839) and 0.447 (95%CI 0.028-7.191) in patients not receiving immunosuppressive therapy (P=0.825). E lesion or diffuse E lesion may not be associated with prognosis or response to immunosuppressive therapy.

[Preliminary analysis on COVID-19 case spectrum and spread intensity in different provinces in China except Hubei province]

Objective: To analyze the characteristics of COVID-19 case spectrum and spread intensity in different provinces in China except Hubei province. Methods: The daily incidence data and case information of COVID-19 were collected from the official websites of provincial and municipal health commissions. The morbidity rate, severity rate, case-fatality rate, and spread ratio of COVID-19 were calculated. Results: As of 20 March, 2020, a total of 12 941 cases of COVID-19 had been conformed, including 116 deaths, and the average morbidity rate, severity rate and case-fatality rate were 0.97/100 000, 13.5% and 0.90%, respectively. The morbidity rates in Zhejiang (2.12/100 000), Jiangxi (2.01/100 000) and Beijing (1.93/100 000) ranked top three. The characteristics of COVID-19 case spectrum varied from province to province. The first three provinces (autonomous region, municipality) with high severity rates were Tianjin (45.6%), Xinjiang (35.5%) and Heilongjiang (29.5%). The case-fatality rate was highest in Xinjiang (3.95%), followed by Hainan (3.57%) and Heilongjiang (2.70%). The average spread ratio was 0.98 and the spread intensity varied from province to province. Tibet had the lowest spread ratio (0), followed by Qinghai (0.20) and Guangdong (0.23). Conclusion: The intervention measures were effective in preventing the spread of COVID-19 and improved treatment effect in China. However, there were significant differences among different regions in severity, case-fatality rate and spread ratio.

Effect of apigenin on surface-associated characteristics and adherence of Streptococcus mutans

Apigenin is a type of flavonols that exhibits anti-caries properties. Bacterial adherence is the initial step in the forming of a stable biofilm that leads to caries. Bacterial adherence is affected by surface characteristics, including hydrophobicity and bacterial aggregation. However, the effect of apigenin on surface characteristics of cariogenic bacteria has not been reported. We aimed to examine the effects of apigenin on adherence and biofilm formation of Streptococcus mutans UA159. Hydrophobicity and bacterial aggregation, pac and gbpC gene expressions, and cytotoxicity on human dental pulp cells were also determined. Apigenin significantly inhibited the adherence and biofilm formation of S. mutans. Hydrophobicity decreased, whereas the aggregation rate was significantly increased compared with the control. Apigenin significantly suppressed pac and gbpC gene expressions. Apigenin exhibited acceptable biocompatibility on hDPCs. Thus, apigeinin may affect adherence and biofilm formation by altering the surface properties of S. mutans without obvious adverse effect on hDPCs.

Automated Measurements of Key Morphological Features of Human Embryos for IVF

A major challenge in clinical In-Vitro Fertilization (IVF) is selecting the highest quality embryo to transfer to the patient in the hopes of achieving a pregnancy. Time-lapse microscopy provides clinicians with a wealth of information for selecting embryos. However, the resulting movies of embryos are currently analyzed manually, which is time consuming and subjective. Here, we automate feature extraction of time-lapse microscopy of human embryos with a machine-learning pipeline of five convolutional neural networks (CNNs). Our pipeline consists of (1) semantic segmentation of the regions of the embryo, (2) regression predictions of fragment severity, (3) classification of the developmental stage, and object instance segmentation of (4) cells and (5) pronuclei. Our approach greatly speeds up the measurement of quantitative, biologically relevant features that may aid in embryo selection.

New perspective to improve dentin-adhesive interface stability by using dimethyl sulfoxide wet-bonding and epigallocatechin-3-gallate

OBJECTIVES

To determine whether dentin-adhesive interface stability would be improved by dimethyl sulfoxide (DMSO) wet-bonding and epigallocatechin-3-gallate (EGCG).

METHODS

Etched dentin surfaces from sound third molars were randomly assigned to five groups according to different pretreatments: group 1, water wet-bonding (WWB); group 2, 50% (v/v) DMSO wet-bonding (DWB); groups 3-5, 0.01, 0.1, and 1 wt% EGCG-incorporated 50% (v/v) DMSO wet-bonding (0.01%, 0.1%, and 1%EGCG/DWB). Singlebond universal adhesive was applied to the pretreated dentin surfaces, and composite buildups were constructed. Microtensile bond strength (μTBS) and interfacial nanoleakage were respectively examined after 24 h water storage or 1-month collagenase ageing. In situ zymography andStreptococcus mutans (S. mutans) biofilm formation were also investigated.

RESULTS

After collagenase ageing, μTBS of groups 4 (0.1%EGCG/DWB) and 5 (1%EGCG/DWB) did not decrease (p > 0.05) and was higher than that of the other three groups (p < 0.05). Nanoleakage expression of groups 4 and 5 was less than that of the other three groups (p < 0.05), regardless of collagenase ageing. Metalloproteinase activities within the hybrid layer in groups 4 and 5 were suppressed. Furthermore, pretreatment with 1%EGCG/DWB (group 5) efficiently inhibited S. mutans biofilm formation along the dentin-adhesive interface.

SIGNIFICANCE

This study suggested that the synergistic action of DMSO wet-bonding and EGCG can effectively improve dentin-adhesive interface stability. This strategy provides clinicians with promising benefits to achieve desirable dentin bonding performance and to prevent secondary caries, thereby extending the longevity of adhesive restorations.

[Analysis on the epidemic factors for COVID-19]

As a new infectious disease, the epidemic process of COVID-19 has a series of special influencing factors and conditions. In this paper, some obvious characteristics of this widespread epidemic are discussed, including the new pathogen making people feel confused, the slow onset bringing confusion to the clinic, the miscellaneous source of infection also causing confusion to prevention and control work, the easy route of transmissions leading to a sharp increase of confirmed cases, the high susceptibility of the population leading to a high incidence, and the natural epidemic process coupled with the complexity of natural factors and the superposition of social factors. The positive and effective prevention and control strategies and measures adopted by China have greatly changed the natural epidemic process and trajectory of this epidemic, which has been highly affirmed by the expert group of the World Health Organization and praised by many countries and international organizations. However, to sum up carefully and think deeply, it will be a long-term and arduous work to plan and realize public health security in China and even the world in the future.

Deep learning detection of prostate cancer recurrence with 18F-FACBC (fluciclovine, Axumin®) positron emission tomography

PURPOSE

To evaluate the performance of deep learning (DL) classifiers in discriminating normal and abnormal ¹⁸F-FACBC (fluciclovine, Axumin®) PET scans based on the presence of tumor recurrence and/or metastases in patients with prostate cancer (PC) and biochemical recurrence (BCR).

METHODS

A total of 251 consecutive ¹⁸F-fluciclovine PET scans were acquired between September 2017 and June 2019 in 233 PC patients with BCR (18 patients had 2 scans). PET images were labeled as normal or abnormal using clinical reports as the ground truth. Convolutional neural network (CNN) models were trained using two different architectures, a 2D-CNN (ResNet-50) using single slices (slice-based approach) and the same 2D-CNN and a 3D-CNN (ResNet-14) using a hundred slices per PET image (case-based approach). Models' performances were evaluated on independent test datasets.

RESULTS

For the 2D-CNN slice-based approach, 6800 and 536 slices were used for training and test datasets, respectively. The sensitivity and specificity of this model were 90.7% and 95.1%, and the area under the curve (AUC) of receiver operating characteristic curve was 0.971 (p < 0.001). For the case-based approaches using both 2D-CNN and 3D-CNN architectures, a training dataset of 100 images and a test dataset of 28 images were randomly allocated. The sensitivity, specificity, and AUC to discriminate abnormal images by the 2D-CNN and 3D-CNN case-based approaches were 85.7%, 71.4%, and 0.750 (p = 0.013) and 71.4%, 71.4%, and 0.699 (p = 0.053), respectively.

CONCLUSION

DL accurately classifies abnormal ¹⁸F-fluciclovine PET images of the pelvis in patients with BCR of PC. A DL classifier using single slice prediction had superior performance over case-based prediction.

[The preliminary analysis on the characteristics of the cluster for the COVID-19]

Since December 2019, COVID-19, a new emerging infection disease, has spread in 27 countries and regions. The clusters of many cases were reported with the epidemic progresses. We collected currently available information for 377 COVID-19 clusters (1 719 cases), excluded the hospital clusters and Hubei cases, during the period from January 1 to February 20, 2020. There were 297 family clusters (79%), case median was 4; 39 clusters of dining (10%), case median was 5; 23 clusters of shopping malls or supermarkets (6%), case median was 13; 12 clusters of work units (3%), case median was 6, and 6 clusters of transportation. We selected 325 cases to estimate the incubation period and its range was 1 to 20 days, median was 7 days, and mode was 4 days. The analysis of the epidemic situation in a department store in China indicated that there was a possibility of patients as the source of infection during the incubation period of the epidemic. From February 5 to 21, 2020, 634 persons were infected on the Diamond Princess Liner. All persons are susceptible to the 2019 coronavirus. Age, patients during the incubation period and the worse environment might be the cause of the cases rising. The progress of the two typical outbreaks clearly demonstrated the spread of the early cases in Wuhan. In conclusion, screening and isolating close contacts remained essential other than clinical treatment during the epidemic. Especially for the healthy people in the epidemic area, isolation was the key.

[Cloning and sequence analysis of leptin receptor overlapping transcript-like 1 gene from Dermatophagoides farinae]

OBJECTIVE

To obtain the leptin receptor overlapping transcript-like 1 encoding gene (LepROTL1 gene) from Dermatophagoides farina, investigate the molecular characteristics of the gene and construct a prokaryotic expression vector to express this gene.

METHODS

The LepROTL1 gene-encoding sequence fragments were captured based on the transcriptome sequencing results, and the full-length gene fragments were amplified from total RNA of D. farinae using a RT-PCR assay, and used to construct the expression plasmid pET28a(+)-LepROTL1, followed by sequencing. The plasmid was transformed into E. coli BL21 (DE3) T1R for the induction of IPTG expression. The expression product was characterized by SDS-PAGE and Western blotting. Bioinformatics analyses were performed to analyze the sequence and the molecular characteristics of its encoded protein.

RESULTS

The amplification products of the RT-PCR assay showed a clear band on agarose gel electrophoresis, and sequencing analysis of the pET28a(+)-LepROTL1 plasmid showed 417 bp in length of the coding gene from the start codon ATG to the termination codon TAA. Following the plasmid transformation into E. coli and induction with IPTG, a specific band was seen on SDS-PAGE, indicating successful expression. Bioinformatics analysis showed that the LepROTL1 gene-encoded protein was composed of 134 amino acids, and had a relative molecular weight of 14 378.13 Da, a hydrophilicity index of 1.149, and certain hydrophobicity. The secondary structure was composed of alpha-helix (19 aa, 14.18%), extended strand (48 aa, 35.82%) and random coil (67 aa, 50.00%). The deduced amino acid sequence was used to obtain homologous genes by BLAST, and the phylogenetic tree showed that D. farinae was clustered with D. pteronyssinus.

CONCLUSIONS

The full-length sequences and expression plasmid of the LepROTL1 gene are obtained, and the molecular features of the gene are demonstrated using bioinformatics analyses, which provide insights into further studies on the gene.

Effects of resveratrol/ethanol pretreatment on dentin bonding durability

To determine the effects of resveratrol/ethanol solution on the durability of resin-dentin bonding interfaces. Sixty-four non-caries third molars were randomly divided into four groups (n = 16) after sectioning, and then pretreated with one of the following concentrations of resveratrol/ethanol solutions: 0 (control group), 1, 10 and 20 mg/mL, followed by a universal adhesive and resin composites. All microtensile samples were divided into three subgroups: immediate group, collagenase ageing group and thermocycled group. The microtensile bond strength (MTBS), failure modes, interfacial nanoleakage and in situ zymography were measured, whereas the inhibitory effects of pretreated dentin slices on S. mutans biofilms were determined by confocal laser scanning microscopy and MTT assay. The results indicated that bonding strength was not only influenced by pretreatment factors (P < 0.05) but also ageing factors (P < 0.05). Regardless of collagenase ageing or thermocycling, the 10 mg/mL resveratrol/ethanol pretreatment group presented significantly higher (P < 0.05) MTBS and lower (P < 0.05) expression of nanoleakage than the control group, showed better inhibitory effect of matrix metalloproteinases and S. mutans activity with acceptable cytotoxicity. Meanwhile, cohesive failure in dentin decreased gradually with increasing resveratrol concentration. Therefore, the resveratrol/ethanol solution had the potential to serve as a versatile dentin primer, which can effectively improve dentin bonding durability and prevent secondary caries.