Porous Complex-Mediated Dual Emission of Porphyrins for the Electrochemiluminescence Bioassay

Although porphyrins make up a promising class of electrochemiluminescence (ECL) luminophors, their aggregation-caused quenching (ACQ) characteristics lead to inferior ECL efficiency (ΦECL). Furthermore, current application of porphyrins is limited to cathodic emission. This work creatively exploited a cage-like porous complex (referred to as SWU-1) as the microreactor to recede the ACQ effect while modulating dual ECL emission of meso-tetra(4-carboxyphenyl)porphine (TCPP), which self-assembled with SWU-1 to form TCPP@SWU-1 nanocapsules (TCPP@SWU-1 NCs). As the microreactor, SWU-1 not only effectively constrained TCPP aggregation to improve electron-hole recombination efficiency but also improved stability of anion and cation radicals, thus significantly enhancing the dual emission of TCPP. Compared with TCPP aggregates, the resulting TCPP@SWU-1 NCs exhibited significantly enhanced anodic and cathodic emission, and their ΦECL was increased by 8.7-fold and 3.9-fold, respectively. Furthermore, black hole quencher-2 (BHQ2) can simultaneously quench anodic and cathodic signals. TCPP@SWU-1 NCs coupling BHQ2 conveniently achieved an ECL ratio detection of miRNA-126, and the limit of detection (S/N = 3) was 4.1 aM. This work pioneered the development of the cage-like porous complex SWU-1 as the microreactor to alleviate defects of the ACQ effect and mediate dual emission of TCPP. The coupling of dual-emitting TCPP@SWU-1 NCs and dual-function moderator BHQ2 created a novel single-luminophor-based ratio system for bioanalysis and provided a promising ECL analysis approach for miRNA-126.

Correlation study between bone metabolic markers, bone mineral density, and sarcopenia

OBJECTIVE

To investigate the correlation between bone metabolism markers, bone mineral density (BMD), and sarcopenia.

METHODS

A total of 331 consecutive patients aged ≥ 60 years who were hospitalized between November 2020 and December 2021 were enrolled. Participants were divided into sarcopenia and non-sarcopenia groups according to the Asian Working Group on Sarcopenia criteria (AWGS, 2019). The clinical data, bone metabolism markers (β-CTX, N-MID, and TP1NP), and BMD were compared between the two groups.

RESULTS

Age, β-CTX, and N-MID of the sarcopenia group were higher than those of the non-sarcopenia group (P < 0.05), but the BMD T values were lower than those of the non-sarcopenia group (P < 0.05). Binary logistic regression analysis showed that increased femoral neck BMD (FNBMD) was a protective factor for sarcopenia, while increased β-CTX was a risk factor. Pearson/Spearman correlation analysis showed that the diagnostic indices of sarcopenia were positively correlated with FNBMD and negatively correlated with β-CTX and N-MID. Multiple linear regression analysis revealed that BMI and FNBMD significantly positively affected muscle strength and appendicular skeletal muscle mass (ASM). The FNBMD significantly positively affected physical performance, while β-CTX significantly negatively affected muscle strength, ASM, and physical performance.

CONCLUSION

Increased FNBMD may be a protective factor against sarcopenia, and increased β-CTX may be a risk factor. The FNBMD significantly positively affected the diagnostic indices of sarcopenia, while β-CTX significantly negatively affected them. BMD and bone metabolism marker levels may be considered in early screening for sarcopenia.

Nickel Single-Atom Catalyst Boosts Electrochemiluminescence of Graphitic Carbon Nitride for Sensitive Detection of HBV DNA

Owing to excellent catalytic activity, single-atom catalysts (SACs) have recently attracted considerable research interest in the electrochemiluminescence (ECL) field. However, the applications of SACs are mostly limited to conventional luminol ECL system. Hence, it is necessary to explore the application of SACs in more ECL systems. In this work, nickel single-atom catalysts (Ni SACs) were successfully applied in the graphitic carbon nitride (g-C3N4)-H2O2 ECL system to significantly enhance its cathodic emission. Notably, g-C3N4 acted not only as an ECL luminophore but also as a support to anchor Ni SACs. Ni SACs can significantly activate H2O2 to produce abundant OH• radicals for enhancing the cathodic ECL emission of g-C3N4. Ni SACs-anchored g-C3N4 (Ni SACs@g-C3N4) had a 10-fold enhanced ECL intensity as compared to g-C3N4. Finally, the Ni SACs@g-C3N4-H2O2 ECL system was developed to detect hepatitis B virus (HBV) DNA by incorporating an entropy-driven DNA walking machine-assisted CRISPR-Cas12a amplification strategy. The constructed biosensor exhibited excellent detection performance for HBV DNA with a limit of detection as low as 17 aM. This work puts forward a new idea for enhancing the cathodic ECL of g-C3N4-H2O2 and expands the application of SACs in the ECL system.

Using CT imaging features to predict visceral pleural invasion of non-small-cell lung cancer

AIM

To examine the diagnostic performance of different models based on computed tomography (CT) imaging features in differentiating the invasiveness of non-small-cell lung cancer (NSCLC) with multiple pleural contact types.

MATERIALS AND METHODS

A total of 1,573 patients with NSCLC (tumour size ≤3 cm) were included retrospectively. The clinical and pathological data and preoperative imaging features of these patients were investigated and their relationships with visceral pleural invasion (VPI) were compared statistically. Multivariate logistic regression was used to eliminate confounding factors and establish different predictive models.

RESULTS

By univariate analysis and multivariable adjustment, surgical history, tumour marker (TM), number of pleural tags, length of solid contact and obstructive inflammation were identified as independent risk predictors of pleural invasiveness (p=0.014, 0.003, <0.001, <0.001, and 0.017, respectively). In the training group, comparison of the diagnostic efficacy between the combined model including these five independent predictors and the image feature model involving the latter three imaging predictors were as follows: sensitivity of 88.9% versus 77% and specificity of 73.5% versus 84.1%, with AUC of 0.868 (95% CI: 0.848-0.886) versus 0.862 (95% CI: 0.842-0.880; p=0.377). In the validation group, the sensitivity and specificity of these two models were as follow: the combined model, 93.5% and 74.3%, the imaging feature model, 77.4% and 81.3%, and their areas under the curve (AUCs) were both 0.884 (95% CI: 0.842-0.919). The best cut-off value of length of solid contact was 7.5 mm (sensitivity 68.9%, specificity 75.5%).

CONCLUSIONS

The image feature model showed great potential in predicting pleural invasiveness, and had comparable diagnostic efficacy compared with the combined model containing clinical data.

Burnout and turnover intention of primary health care providers during the COVID-19 pandemic in China

OBJECTIVES

This study explored the changes and new characteristics of burnout and turnover intention of primary health care (PHC) providers during the COVID-19 pandemic in China.

STUDY DESIGN

This was a cross-sectional study.

METHODS

This study investigated 1326 PHC providers during the COVID-19 outbreak in 2022 in one district of Shanghai, China. Independent t-test or one-way analysis of variance (ANOVA) test were used to analyse the between-group variation of variables associated to burnout and turnover intention. Then, hierarchical regression analysis was used to further determine the impact of certain variables on burnout and turnover intention, the relationship of burnout on turnover intention and the possible moderating effect.

RESULTS

The results showed that there was no significant change in the prevalence of overall burnout of PHC providers compared to the pre-epidemic period; however, there was a significant increase in high-level burnout. No significant change in turnover intention at the moderate level and above was observed. During the COVID-19 pandemic, PHC providers who were older, married, local and had a higher skill level had higher burnout, while PHC providers who were male, unmarried, non-local and separated from their family had a higher turnover intention. It was shown that burnout, with its three sub-dimensions, was a good predictor of turnover intention. The impact of burnout on turnover intention was shown to be alleviated by certain variables, including being married, living locally and receiving benefit packages, including the preferential education policy for children and talent incentive policies.

CONCLUSIONS

Results from this study have highlighted the importance of paying attention to vulnerable groups of PHC providers, for example those who are separated from their families, during emergency situations. Various incentive tools could be comprehensively used to ensure the stability and efficiency of PHC human resources.

Coreactant-free dual-emitting conjugated polymer for ratiometric electrochemiluminescence detection of SARS-CoV-2 RdRp gene

Constructing mono-luminophor-based electrochemiluminescence (ECL) ratio system is a great challenge due to the limitations of the luminescent species with dual-signal-output, luminescence efficiency and coreactant. This work developed carboxyl-functionalized poly[9,9-bis(3'-(N,N-dimethylamino) propyl)-2,7-fluorene]-alt-2,7-(9,9 dioctylfluorene)] nanoparticles(PFN NPs) as dual-emitting luminophors, which can synchronously output strong cathodic and anodic ECL signals without any exogenous coreactants. The inherent molecular structure enabled efficient intramolecular electron transfer between tertiary amine groups and backbone of PFN to generate strong cathodic and anodic ECL emission. Particularly, H+ in aqueous solution played an irreplaceable role for cathodic ECL emission. The silver nanoparticles (AgNPs) were developed as signal regulator because of their excellent hydrogen evolution reaction (HER) activity, which significantly quenched the cathodic signal while kept the anodic signal unchanged. The dual-emitting PFN NPs cleverly integrated signal regulator AgNPs and bicyclic strand displacement amplification (SDA) to construct a coreactant-free mono-luminophor-based ratiometric ECL sensing for SARS-CoV-2 RdRp gene assay. The strong dual-emitting of PFN NPs and excellent quenching effect of AgNPs on cathodic emission endowed the biosensor with a high detection sensitivity, and the detection limit was as low as 39 aM for RdRp gene. The unique dual-emitting properties of PFN NPs open up a new path to construct coreactant-free mono-luminophor-based ECL ratio platform, and excellent HER activity of AgNPs offers some new thoughts for realizing ECL signal changes.

CREB3L2 Regulates Hemidesmosome Formation during Epithelial Sealing

The long-term success rate of dental implants can be improved by establishing a favorable biological sealing with a high-quality epithelial attachment. The application of mesenchymal stem cells (MSCs) holds promise for facilitating the soft tissue integration around implants, but the molecular mechanism is still unclear and the general application of MSC sheet for soft tissue integration is also relatively unexplored. We found that gingival tissue-derived MSC (GMSC) sheet treatment significantly promoted the expression of hemidesmosome (HD)-related genes and proteins in gingival epithelial cells (GECs). The formation of HDs played a key role in strengthening peri-implant epithelium (PIE) sealing. Further, high-throughput transcriptome sequencing showed that GMSC sheet significantly upregulated the PI3K/AKT pathway, confirming that cell adhesion and HD expression in GECs were regulated by GMSC sheet. We observed that the expression of transcription factor CREB3L2 in GECs was downregulated. After treatment with PI3K pathway inhibitor LY294002, CREB3L2 messenger RNA and protein expression levels were upregulated. Further experiments showed that overexpression or knockdown of CREB3L2 could significantly inhibit or promote HD-related genes and proteins, respectively. We confirmed that CREB3L2 was a transcription factor downstream of the PI3K/AKT pathway and participated in the formation of HDs regulated by GMSC sheet. Finally, through the establishment of early implant placement model in rats, we clarified the molecular function of CREB3L2 in PIE sealing as a mechanical transmission molecule in GECs. The application of GMSC sheet-implant complex could enhance the formation of HDs at the implant-PIE interface and decrease the penetration distance of horseradish peroxidase between the implant and PIE. Meanwhile, GMSC sheet reduced the length of CREB3L2 protein expression on PIE. These findings elucidate the potential function and molecular mechanism of MSC sheet regulating the epithelial sealing around implants, providing new insights and ideas for the application of stem cell therapy in regenerative medicine.

Prediction of Lymphopenia and Survival with Baseline Absolute Lymphocyte Count and Irradiated Dose to Immune Cells in Patients with Non-Small Cell Lung Cancer Treated with Concurrent Chemoradiotherapy

PURPOSE/OBJECTIVE(S)

This study aimed to investigate the effect of effective dose to immune cell (EDIC) combined with pre-radiotherapy (RT) absolute lymphocyte count (ALC) on treatment-related lymphopenia during RT and treatment outcome in patients with locally advanced non-small cell lung cancer (NSCLC). A subgroup analysis in patients who received consolidation immunotherapy was also conducted.

MATERIALS/METHODS

Between August 2008 and December 2021, 517 patients with locally advanced NSCLC treated with definitive concurrent chemoradiotherapy (CRT) were retrospectively analyzed. All patients had serial complete-blood-count tests at pre-, and during-CRT. Severe lymphopenia was defined as ALC < 0.5x109cells/L during RT. EDIC was calculated according to mean doses of the lung, heart and the total body. The patients were grouped according to high and low EDIC and pre-RT ALC and was assessed for its correlation with radiation induced lymphopenia and survival outcomes.

RESULTS

Of 517 eligible patients, most of the patients received weekly paclitaxel with carboplatin (90.3%) and 195 patients (37.7%) received consolidation immunotherapy following CRT. A median radiation dose of 63 Gy (IQR, 60-64.5) was delivered in 30 fractions. The optimal cutoff value of EDIC and pre-RT ALC for predicting severe lymphopenia were 2.89 Gy and 2.03x109cells/L, respectively. High risk group was defined as EDIC ≥ 2.89 Gy and pre-RT ALC < 2.03x109cells/L, low risk group as EDIC <2.89 Gy and pre-RT ALC ≥ 2.03x109cells/L, and intermediate group as EDIC ≥ 2.89 Gy and pre-RT ALC ≥ 2.03x109cells/L or EDIC < 2.89 Gy and pre-RT ALC < 2.03x109cells/L. The incidence of severe lymphopenia during RT in high, intermediate, and low risk group was 90.1%, 77.1%, and 52.3%, respectively (p<0.001). The risk groups were independent predictors for both progression-free survival (PFS) (p<0.001) and overall survival (OS) (p<0.001). The high-risk group had higher incidence of locoregional and distant recurrences (p<0.001). In the subset of patients who were treated with consolidation immunotherapy, the risk groups were predictive of severe lymphopenia (p = 0.001), PFS (p = 0.004), and OS (p = 0.012).

CONCLUSION

This study demonstrated that the combination of EDIC and pre-RT ALC is a predictor for severe lymphopenia during RT, recurrence, and survival in patients with locally advanced NSCLC who received CRT. Moreover, the combination of EDIC and pre-RT ALC may serve as a potential biomarker for the benefit of maintenance immunotherapy.

Fluorapatite nanorod arrays with enamel-like bundle structure regulated by iron ions

Pigmented rodent tooth enamel is mainly composed of parallel hydroxyapatite nanorods and a small amount of organic matrix. These hydroxyapatite nanorods tend to be carbonated and contain traces of iron, fluorine, and magnesium. The pigmented rodent tooth enamel which contains trace iron is stronger and more resistant to acid corrosion than unpigmented rodent enamel, which could provide inspiration for the preparation and synthesis of high performance and corrosion resistant artificial materials. However, the regulatory role and mechanical enhancement of iron ions in enamel growth are unclear. Here, we synthesized enamel-like fluorapatite nanorod arrays in vitro using a mineralization technique at room-temperature. To investigate the regulatory effect of iron ions on the fluorapatite nanorod arrays (FAP-Fe), the phosphate solution is slowly transfused dropwise in the calcium ion solution, and different concentrations of iron ions are added to the calcium ion solution in advance. We demonstrated that fluorapatite nanorod arrays (FAP) can be epitaxially grown from amorphous calcium phosphate nanoparticles and iron ions can improve the microstructure of FAP nanorod arrays and obtain the same enamel bundle structure as the natural enamel. Moreover, high concentration of iron ions can inhibit the crystallization of fluorapatite. The FAP-Fe nanorod arrays controlled by 0.02 mM Fe3+ have good mechanical properties. Their hardness is 1.34 ± 0.02 GPa and Young's modulus is 65.3 ± 0.4 GPa, respectively. This work is helpful to understand the role of trace elements in natural enamel in the regulation of enamel formation and to provide a theoretical foundation for the preparation of high strength artificial composites, which can play a greater role in the fields of biological alternative materials, anti-oil coating, oil/water separation, anti-bioadhesion and so on.

Measurements of neutrino oscillation parameters from the T2K experiment using 3.6×1021 protons on target

The T2K experiment presents new measurements of neutrino oscillation parameters using 19.7 ( 16.3 ) × 10 20 protons on target (POT) in (anti-)neutrino mode at the far detector (FD). Compared to the previous analysis, an additional 4.7 × 10 20 POT neutrino data was collected at the FD. Significant improvements were made to the analysis methodology, with the near-detector analysis introducing new selections and using more than double the data. Additionally, this is the first T2K oscillation analysis to use NA61/SHINE data on a replica of the T2K target to tune the neutrino flux model, and the neutrino interaction model was improved to include new nuclear effects and calculations. Frequentist and Bayesian analyses are presented, including results on sin 2 θ 13 and the impact of priors on the δ CP measurement. Both analyses prefer the normal mass ordering and upper octant of sin 2 θ 23 with a nearly maximally CP-violating phase. Assuming the normal ordering and using the constraint on sin 2 θ 13 from reactors, sin 2 θ 23 = 0 . 561 - 0.032 + 0.021 using Feldman-Cousins corrected intervals, and Δ m 32 2 = 2 . 494 - 0.058 + 0.041 × 10 - 3 eV 2 using constant Δ χ 2 intervals. The CP-violating phase is constrained to δ CP = - 1 . 97 - 0.70 + 0.97 using Feldman-Cousins corrected intervals, and δ CP = 0 , π is excluded at more than 90% confidence level. A Jarlskog invariant of zero is excluded at more than 2 σ credible level using a flat prior in δ CP , and just below 2 σ using a flat prior in sin δ CP . When the external constraint on sin 2 θ 13 is removed, sin 2 θ 13 = 28 . 0 - 6.5 + 2.8 × 10 - 3 , in agreement with measurements from reactor experiments. These results are consistent with previous T2K analyses.

[Long term follow-up evaluation of combined surgery for congenital tibial pseudarthrosis in children]

Objective: To explore the long-term effect of combined surgery for the treatment of congenital tibial pseudarthrosis in children. Methods: The clinical data of 44 children with congenital tibial pseudarthrosis who underwent combined surgery (tibial pseudarthrosis tissue resection, intramedullary rod fixation, Ilizarov external fixator fixation, wrapped autologous iliac bone graft) from August 2007 to October 2011 at the Department of Pediatric Orthopedics, Hunan Children's Hospital were collected retrospectively. There were 33 males and 11 females. The age at the time of surgery was (3.7±2.2)years (range:0.6 to 12.4 years), including 25 cases under 3 years old and 19 cases above 3 years old.Among them, 37 cases were complicated with neurofibromatosis type 1.The operation status, postoperative complications and follow-up results were recorded. Results: The follow-up time after surgery was (10.9±0.7)years (range:10 to 11 years).Thirty-nine out of 44 patients (88.6%) achieved initial healing of tibial pseudarthrosis, with an average healing time of (4.3±1.1)months (range:3 to 10months).In the last follow-up, 36 cases (81.8%) had unequal tibial length, 20 cases (45.4%) had refractures, 18 cases (40.9%) had ankle valgus, 9 cases (20.4%) had proximal tibial valgus, and 11 cases (25.0%) had high arched feet.Nine cases (20.4%) developed distal tibial epiphyseal plate bridging.17 cases (38.6%) had abnormal tibial mechanical axis.Seven cases (15.9%) developed needle infection, and one case (2.3%) developed tibial osteomyelitis. 21 patients (47.7%) had excessive growth of the affected femur.Five patients (11.3%) had ankle stiffness, and 34 patients (77.2%) had intramedullary rod displacement that was not in the center of the tibial medullary cavity.Among them, 8 cases (18.1%) protruded the tibial bone cortex and underwent intramedullary rod removal.18 children have reached skeletal maturity, while 26 children have not been followed up until skeletal maturity. Conclusion: Combined surgery for the treatment of congenital pseudarthrosis of the tibia in children has a high initial healing rate, but complications such as unequal tibia length, refracture, and ankle valgus occur during long-term follow-up, requiring multiple surgical treatments.

Mutational landscape of SWI/SNF complex genes reveal correlation to predictive biomarkers for immunotherapy sensitivity in lung adenocarcinoma patients

BACKGROUND

The search for prognostic biomarkers indicating sensitivity to immunotherapy in lung adenocarcinoma patients has zeroed in on genes in the switch/sucrose non-fermentable (SWI/SNF) pathway. The mutational profiles of key genes are not clearly defined, however, and no comparisons have been conducted on whether mutations in the genes involved provide the same predictive value.

METHODS

In this study, analysis of clinical factors, tumor mutation burden (TMB), chromosomal instability, and co-alterations was conducted for 4344 lung adenocarcinoma samples. Independent online cohorts (N = 1661 and 576) were used to supplement the analysis with survival and RNA-seq data.

RESULTS

Mutational burden and chromosomal instability analysis showed that ARID family mutations (including ARID1A, ARID1B, or ARID2 mutations) and SMARC family mutations (including SMARCA4 or SMARCB1 mutations) display different profiles from wild-type (WT) samples (TMB: ARID versus WT: P < 2.2 × 10^-16, SMARC versus WT: P < 2.2 × 10^-16; CIN: ARID versus WT: P = 1.8 × 10^-5, SMARC versus WT: P = 0.027). Both mutant groups have a higher proportion of transversions than transitions, whereas the ratio is more equal for wild-type samples. Survival analysis shows that patients with ARID mutations were more sensitive to immunotherapy treatment than wild-type and SMARC-mutated patients (P < 0.001 and P = 0.013, respectively), and multivariate Cox analysis reveals that the presence of ARID mutations is likely the main cause.

CONCLUSIONS

The research presented in this study shows that mutations in the ARID gene family, including ARID1A, ARID1B, and ARID2, are primarily responsible for the sensitive response to immunotherapy treatment in patients with lung adenocarcinoma.

[Application and research progress of autologous soft tissue substitute materials in gingival augmentation of natural teeth]

Subepithelial connective tissue or free gingival grafts are often used in traditional mucogingival surgery to treat gingival recession and keratinized gingival insufficiency. However, due to the disadvantages of autologous soft tissue grafts, such as the preparation of the second surgical site, the limited amount of tissue in the donor site, and postoperative discomfort for patients, the research on autologous soft tissue substitute materials has attracted extensive attention. A variety of donor-substitute materials from different sources are currently used in membranous gingival surgeries, including platelet-rich fibrin, acellular dermal matrix, xenogeneic collagen matrix, etc. This paper reviews the research progress and application of several different types of substitute materials in soft tissue augmentation for natural teeth, providing a reference for the application of autologous soft tissue substitutes in clinical gingival augmentation surgery.

Alloreactivity and autoreactivity converge to support B cell epitope targeting in transplant rejection

Antibody (Ab) responses against human leukocyte antigen (HLA) proteins mismatched between donor and recipient are leading cause of allograft loss in kidney transplantation. However, therapies targeting alloreactive B cell and Ab-secreting cell (ASC) are lacking, motivating the need to understand how to prevent and abrogate these alloresponses. Using molecular, structural, and proteomic techniques, we profiled the B cell response in a kidney transplant recipient with antibody-mediated rejection and graft loss. We found that this response spanned the rejected organ and peripheral blood, stimulated the differentiation of multiple B cell subsets, and produced a high-affinity, donor-specific, anti-HLA response. We found epitopic immunodominance that relied on highly exposed, solvent-accessible mismatched HLA residues as well as structural and biomolecular evidence of autoreactivity against the recipient's self-HLA allele. These alloreactive and autoreactive signatures converged in the recipient's circulating donor-specific Ab repertoire, suggesting that rejection requires both the recognition of non-self and breaches of tolerance to lead to alloinjury and graft loss.

[Optimized pathway to schistosomiasis elimination in China: a scrutiny using a marginal benefit approach]

Following concerted efforts for over 7 decades, great achievements have been gained in the national schistosomiasis control program of China. Currently, China is moving towards the stage of schistosomiasis elimination, when the major task is to make full use of available resources to improve schistosomiasis surveillance and response to sustainably consolidate gained schistosomiasis control achievements and prevent re-emerging schistosomiasis. There is therefore an urgent need for optimization of interventions for schistosomiasis elimination. Based on analysis of socioeconomic features at different stages of the national schistosomiasis control program in China, this review discusses the relationship between the needs of assessment of schistosomiasis elimination interventions and the optimized strategy of schistosomiasis elimination at different stages of the national schistosomiasis control program using a marginal benefit approach and proposes the optimized schistosomiasis elimination strategy that allows the highest marginal benefit with currently available schistosomiasis elimination costs, so as to provide the optimal strategic pathway to schistosomiasis elimination and facilitate the achievement of the targets set in Healthy China 2030.

Coreactant-free electrochemiluminescence of polyfluorene nanoparticle coupling double quencher for β-amyloid1-42 detection

β-amyloid_1-42 (Aβ_1-42) is a humoral biomarker for early diagnosis of Alzheimer's disease (AD), and exists at a low level in human body. Its sensitive detection is very valuable. The electrochemiluminescence (ECL) assay of Aβ_1-42 has attracted special attention owing to high sensitivity and simple operation. However, currently reported ECL assays for Aβ_1-42 usually required the introduction of exogenous coreactants to improve the detection sensitivity. Introducing exogenous coreactants will lead to non-negligible repeatability and stability problems. This work exploited poly [(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,1',3}-thiadazole)] nanoparticles (PFBT NPs) as coreactant-free ECL emitters for detecting Aβ_1-42. The PFBT NPs, first antibody (Ab₁) and antigen Aβ_1-42 were successively assembled on glassy carbon electrode (GCE). Silica nanoparticles served as a carrier to grow polydopamine (PDA) in situ, and further assembled Au nanoparticles (Au NPs) and second antibody (Ab₂), producing the secondary antibody complex (SiO₂@PDA-Au NPs-Ab₂). With its assembly on the biosensor, the ECL signal decreased since both PDA and Au NPs could quench ECL emission from PFBT NPs. The limit of detection (LOD) of 0.55 fg/mL and limit of quantification (LOQ) of 37.45 fg/mL for Aβ_1-42 were obtained. PFBT NPs coupling dual-quencher PDA-Au NPs created an excellent ECL system for bioassays, and constructed a sensitive analytical method for Aβ_1-42.

Downregulated FGFR3 Expression Inhibits In Vitro Osteogenic Differentiation of Bone Marrow Mesenchymal Stem Cells of Mice with TBXT Gene Mutation

We studied the effect of fibroblast growth factor receptor 3 (FGFR3) inhibitor BGJ-398 on the differentiation of bone marrow mesenchymal stem cells (BM MSC) into osteoblasts in wild type (wt) mice and in animals with mutation in TBXT gene (mt) and possible differences in the pluripotency of these cells. Cytology tests showed that the cultured BM MSC could differentiate into osteoblasts and adipocytes. The effect of different BGJ-398 concentrations on the expression of FGFR3, RUNX2, SMAD1, SMAD4, SMAD5, SMAD6, SMAD7, and SMAD8 were studied by quantitative reverse transcription PCR. The expression of RUNX2 protein was evaluated by Western blotting. BM MSC of mt and wt mice did not differ in pluripotency and expressed the same membrane marker antigens. BGJ-398 inhibitor reduced the expression of FGFR3 and RUNX2. In BM MSC from mt and wt mice have similar gene expression (and its changing) in FGFR3, RUNX2, SMAD1, SMAD4, SMAD5, SMAD6, SMAD7, and SMAD8 genes. Thus, our experiments confirmed the effect of decreased expression of FGFR3 on osteogenic differentiation of BM MSC from wt and mt mice. However, BM MSC from mt and wt mice did not differ in pluripotency and are an adequate model for laboratory research.

Oxidative stress mediated immunosuppression caused by ammonia gas via antioxidant/oxidant imbalance in broilers

1. Ammonia is one of major air pollutants in intensive poultry houses, where it causes immunosuppression in broilers. Although previous studies have focused on a particular organ, data on multiple organs have not been reported.2. In the following work, broilers were exposed to environmental ammonia (0, 10, 20, and 40 mg/m³ from 1-21 d old; and 0, 15, 30, and 60 mg/m³ from 22-42 d old).3. Ammonia exposure reduced bird spleen index at 42 d and thymus index at 14, 28, 35 and 42 d, meaning that ammonia caused immunosuppression in birds. Moreover, high ammonia exposure down-regulated the expression of toll-like receptor 4 (TLR4) in lung tissue at 21 d, as well as TLR4 in lung and tracheal mucosa at 42 d when analysed using qRT-PCR. It increased SIgA in saliva at 42 d when analysed by ELISA. Ammonia increased interleukin-6 (IL-6), IL-1β, interferon-α (IFN-α), and IFN-γ in serum at 28 d from the ELISA assay, which indicated that all of these factors took part in ammonia-immunosuppression in birds.4. Three antioxidants (CAT, SOD, T-AOC) decreased, and one oxidant MDA increased after ammonia exposure in the liver and blood, which indicated that ammonia caused oxidative stress via the imbalance of antioxidants/oxidants in birds.5. Correlation analysis showed that TLR4 and TLR15 in the tracheal mucosa were significantly positively related to IFN-γ and negatively related to IL-6. TLR2 in the lung was significantly positively related to IL-1β, and TLR2 in bird tracheal mucosa was negatively related to IL-6 in serum.6. The results suggested that oxidative stress mediated immunosuppression caused by ammonia gas via antioxidant/oxidant imbalance in broilers.

Hybrid Exercise Program Enhances Physical Fitness and Reverses Frailty in Older Adults: Insights and Predictions from Machine Learning

PURPOSE

The declining physical condition of the older adults is a pressing issue. Wu Qin Xi exercise, despite being low-intensity, is highly effective among older adults. Inspired by its characteristics, we designed a new exercise program for frail older adults, combining strength, endurance, and Wu Qin Xi. Furthermore, we employed machine learning to predict whether frailty can be reversed in older adults after the intervention.

METHODS

A total of 181 community-dwelling frail older adults aged 65 years or older participated in this single-center, randomized controlled study, with 54.7% (n=99) being female. The study assessed the effectiveness of several exercise modalities in reversing frailty. The Fried's frailty criterion was used to assess the degree of frailty of the subjects. Participants were assigned a three-digit code 001-163 and randomly assigned (1:1:1) by computer to three different groups based on the study participant number: the Wu Qin Xi group (WQX), the strength exercise mixed with endurance exercise training group (SE), and the WQXSE hybrid exercise group incorporated the above two. Body composition and frailty-related physical fitness factors were measured before and after a 24-week intervention. The measurements included Body height, Body mass, Timed Up and Go Test (TUGT), grip strength assessment (GS), 6min walk test (6 min WT), and 10 m maximum walk speed (10 m MWS). Data were analyzed using repeated measures ANOVA to determine group and time interaction effects and machine learning models were used to predict program effectiveness.

RESULTS

A total of 163 participants completed the study, with 53.9% (n=88) of them being female. The two items, 10 m maximum walking speed (10 m MWS) and grip strength, were significantly affected by the interaction of group and time. Compared to the other two groups, the WQXSE group showed the most improvement in the item 10 m MWS. In addition, following 24 weeks of training, 68 (41.7%) of the initially frail older adults had reversed their frailty status. Among them, 19 (36.5%) were in the WQX group, 24 (44.4%) were in the WQXSE group, and 25 (43.9%) were in the SE group. The stacking model exhibited superior performance when compared to other algorithms.

CONCLUSION

A hybrid exercise regimen comprising the Wu Qin Xi routine and exercises focused on both strength and endurance holds the potential to yield greater improvements in the physical fitness of older adults, as well as reducing frailty. Leveraging a stacking model, it is possible to forecast the likelihood of older adults successfully reversing their frailty status following participation in a prevention exercise program.

[Efficacy analysis of high-sensitivity troponin I concentration and its changes in the diagnosis of acute myocardial infarction]

Objective: To explore the feasibility and accuracy of 0-1 h high sensitivity cardiac troponin I (hs-cTnI) concentration and its changes in judging non-ST segment elevation myocardial infarction (NSTEMI), and to investigate the feasibility of a simplified process. Methods: Patients with acute chest pain and suspected NSTEMI who were admitted to the emergency department of Fuwai Hospital, the First Affiliated Hospital of Sun Yat-sen University and Nanjing First Hospital from January 2017 to September 2020 were selected. Hs-cTnI test was carried out for the selected patients at the time of visit (0 h) and 1 h after visit. According to the 0-1 h hs-cTnI diagnostic process and threshold standard recommended by European Society of Cardiology (ESC) guidelines in 2015, the laboratory adjudication was determined. Cardiologists who did not participate in the project design and did not know the results of hs-cTnI test performed the clinical judgment according to the routine diagnosis and treatment process of emergency department. Taking clinical judgment as the gold standard, the diagnostic efficacy of 0-1 h hs-cTnI concentration and its change recommended by the guidelines for judging NSTEMI in Chinese population was analyzed. The guide process was simplified. Under the condition of not considering the time of chest pain, the guideline threshold was used for test and judgement, and the diagnostic efficacy of the simplified process was evaluated. Results: A total of 1 534 patients were enrolled in the study, aged (62±12) years and 952 (62.1%) patients were male. Among them, 402 patients (26.2%) were clinically diagnosed as NSTEMI and 1 132 patients (73.8%) were diagnosed as non-NSTEMI. According to the diagnosis and determination process recommended by the guidelines, NSTEMI was excluded in 672 patients (42.8%), and 464 patients (30.2%) were diagnosed as NSTEMI. The consistency rate with clinical determination reached 92.4% (1 050/1 136), the sensitivity of excluding diagnosis was 99.5% (95%CI: 98.0%-99.9%), the negative predictive value was 99.7% (95%CI: 98.8%-99.9%), and the negative likelihood ratio was 0.008 (95%CI: 0.002-0.335). The diagnostic specificity was 92.6% (95%CI: 90.9%-94.0%), the positive predictive value was 81.9% (95%CI: 78.0%-85.2%), and the positive likelihood ratio was 12.739 (95%CI: 10.356-15.670). According to the simplified process, NSTEMI was excluded in 675 patients (44.0%), and 463 patients (30.2%) were diagnosed as NSTEMI. The consistency rate with clinical judgment was 92.4% (1 051/1 138), the sensitivity of exclusion diagnosis was 99.3% (95%CI: 97.6%-99.8%), the negative predictive value was 99.6% (95%CI: 98.6%-99.9%), and the negative likelihood ratio was 0.012 (95%CI: 0.004-0.389). The diagnostic specificity was 92.6% (95%CI: 90.9%-94.0%), the positive predictive value was 81.9% (95%CI: 78.0%-85.2%), and the positive likelihood ratio was 12.705 (95%CI: 10.328-15.630). There was no significant difference in diagnostic efficacy between the simplified process and the recommended process (all P>0.05). Conclusion: The diagnostic process for judging NSTEMI according to the 0-1 h hs-cTnI concentration and its change criteria recommended by the 2015 ESC guidelines is applicable in the Chinese population and remains highly accurate in judging NSTEMI without considering the duration of chest pain at the time of presentation.

Dual-emitting Iridium nanorods combining dual-regulating coreaction accelerator Ag nanoparticles for electrochemiluminescence ratio determination of amyloid-β oligomers

Iridium(III) complexes have been developed as eminent electrochemiluminescence (ECL) luminophores, but their current applications are only limited to anodic ECL emission because of weak cathodic ECL emission. This work explored poly(styrene-co-maleicanhydride) (PSMA) as functional reagent to modulate iridium(III) complexes to simultaneously emit bipolar ECL signals. The prepared iridium(III) nanorods (Ir NRs) were detected strong bipolar ECL emissions at +0.9 V and -2.0 V with N,N-diisopropylethylenediamine (DPEA) and persulfate (S₂O₈^2-) as coreactant, respectively. Meanwhile, Ag nanoparticles (Ag NPs) were developed as dual-regulating coreaction accelerator to boost the bipolar emissions of Ir NRs simultaneously. The dual-emitting Ir NRs coupled with dual-regulating coreaction accelerator Ag NPs facilitated the construction of mono-luminophore-based ECL ratio strategy for detecting amyloid-β oligomers (AβO). When the target AβO appeared, the Mg²⁺-dependent DNAzyme-powered biped walkers were unlocked to cleave single-stranded S1 immobilized on the surface of magnetic beads (MBs), resulting in the production of massive single-stranded ST. Then, the output ST cleaved hairpin H1 captured by Ir NRs modified electrode to produce numerous single strands, which could initiate the hybridization chain reaction (HCR) between Ag NPs-labeled H2 and Ag NPs-labeled H3 to introduce abundant Ag NPs onto the electrode surface. Due to the enhancement effect of Ag NPs on the bipolar ECL emissions from Ir NRs, the ECL ratio detection of AβO was achieved with the detection limit of 0.62 pM. The unique dual-emitting properties of Ir NRs coupled with dual-regulating effect of Ag NPs provided an interesting mono-luminophore-based ECL ratio sensing platform for biological analysis.

Scintillation light detection in the 6-m drift-length ProtoDUNE Dual Phase liquid argon TPC

DUNE is a dual-site experiment for long-baseline neutrino oscillation studies, neutrino astrophysics and nucleon decay searches. ProtoDUNE Dual Phase (DP) is a 6  ×  6  ×  6 m 3 liquid argon time-projection-chamber (LArTPC) that recorded cosmic-muon data at the CERN Neutrino Platform in 2019-2020 as a prototype of the DUNE Far Detector. Charged particles propagating through the LArTPC produce ionization and scintillation light. The scintillation light signal in these detectors can provide the trigger for non-beam events. In addition, it adds precise timing capabilities and improves the calorimetry measurements. In ProtoDUNE-DP, scintillation and electroluminescence light produced by cosmic muons in the LArTPC is collected by photomultiplier tubes placed up to 7 m away from the ionizing track. In this paper, the ProtoDUNE-DP photon detection system performance is evaluated with a particular focus on the different wavelength shifters, such as PEN and TPB, and the use of Xe-doped LAr, considering its future use in giant LArTPCs. The scintillation light production and propagation processes are analyzed and a comparison of simulation to data is performed, improving understanding of the liquid argon properties.

Investigation on knowledge level about rational use of antimicrobial drugs among pharmacists in medical institutions in Shanxi province, China

OBJECTIVE

To investigate the pharmacist's knowledge about rational use of antimicrobials in Shanxi of China, so as to find out the problems and provide support for the management of antimicrobials.

METHODS

A questionnaire survey was conducted, which included the basic information of the respondents, the basic knowledge about antimicrobial management and the related knowledge about antimicrobial drugs. SPSS 25.0 was used for statistical analysis.

RESULTS

A total of 462 pharmacists were investigated. The average score of the knowledge related to rational use of antimicrobials was 10.49 ± 4.05. It showed that the hospital type, grade, pharmacist's education, professional title and years of experience had effect on the pharmacist's knowledge level about antimicrobial drugs (P < 0.05). Multivariable logistic regression analysis showed that hospital grade and pharmacist's education were the main influencing factors (P < 0.05).

CONCLUSION

Pharmacists have insufficient knowledge about the rational use of antibacterial drugs. It is essential to strengthen the training in management regulations and application of antibacterial drugs.

[Clinical characteristics and long-term follow-up results of radiofrequency ablation for the treatment of ventricular tachycardia in patients with arrhythmogenic left ventricular cardiomyopathy]

Objective: To investigate the acute and long-term outcome of catheter ablation for the treatment of ventricular tachycardia (VT) in patients with arrhythmogenic left ventricular cardiomyopathy (ALVC). Methods: This retrospective, cross-sectional study enrolled ALVC patients undergoing radiofrequency ablation for the treatment of VT at the First Affiliated Hospital of Nanjing Medical University from January 2011 to December 2018 and collected their clinical characteristics and intraoperative electrophysiological examination. Patients were followed up every 6 months after radiofrequency ablation until August 2021. Echocardiographic results and VT recurrence post radiofrequency ablation were analysed. Results: Totally 12 patients were enrolled (mean age: (42±15) years, 11 males(11/12)). The mean of left ventricular end diastolic diameter (LVDd) and left ventricular ejection fraction (LVEF) were (51±5)mm and (65±5)%, respectively. Twelve VTs were induced in 10 patients during the electrophysiological study, and the mean tachycardia cycle length was (293±65) ms. Three-dimensional substrate mapping revealed the diseased area at endocardial site in one patient, at epicardial sites in the other 11 patients (involved endocardial sites in 2 cases) with the basal part near the mitral annulus being the predilection for the substrate (10/11). After the catheter ablation at the endocardial and epicardial sites respectively, the complete procedure endpoint was achieved in all patients (VT cannot be induced post ablation). The median follow-up time was 65 (25, 123) months. One patient was lost to follow-up, and the other 11 patients survived without VT. No significant cardiac function deterioration was detected by the echocardiographic examination ((51±5)mm vs. (52±5)mm, P>0.05 for LVDd, (65±5)% vs. (60±6)%, P>0.05 for LVEF) at the end of follow-up. Conclusion: After radiofrequency ablation, the complete procedure endpoint is achieved in ALVC patients, and the catheter ablation provides long-term ventricular tachycardia control during the long-term follow-up.

Probing ^{93m}Mo Isomer Depletion with an Isomer Beam

The isomer depletion of ^{93m}Mo was recently reported [Chiara et al., Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483] as the first direct observation of nuclear excitation by electron capture (NEEC). However, the measured excitation probability of 1.0(3)% is far beyond the theoretical expectation. In order to understand the inconsistency between theory and experiment, we produce the ^{93m}Mo nuclei using the ^{12}C(^{86}Kr,5n) reaction at a beam energy of 559 MeV and transport the reaction residues to a detection station far away from the target area employing a secondary beam line. The isomer depletion is expected to occur during the slowdown process of the ions in the stopping material. In such a low γ-ray background environment, the signature of isomer depletion is not observed, and an upper limit of 2×10^{-5} is estimated for the excitation probability. This is consistent with the theoretical expectation. Our findings shed doubt on the previously reported NEEC phenomenon and highlight the necessity and feasibility of further experimental investigations for reexamining the isomer depletion under low γ-ray background.

Potentially tunable ratiometric electrochemiluminescence sensing based on conjugated polymer nanoparticle for organophosphorus pesticides detection

In general, suitable double luminophores and their coreactants are necessary for constructing electrochemiluminescence (ECL) ratio strategy. However, the complexity of matching double luminophores and the stability and repeatability problem suffered by introducing exogenous coreactant would greatly limit the application of ratio detection. An original single-luminophore-based ECL ratio sensing was developed excluding any exogenous coreactants in this work. The poly [9,9-bis(3'-(N,N-dimethylamino)propyl)- 2,7-fluorene]-alt-2,7-(9,9-dioctylfluorene)] nanoparticles (PFN NPs) were explored to emit two anodic ECL signals. One centered at + 1.25 V (ECL-1) with the scanning potential of 0 ~ + 1.25 V and the other at + 1.95 V (ECL-2) with the scanning potential of 0 ~ + 1.95 V. ECL-1 showed a very strong emission without any exogenous coreactant. Importantly, hydrogen peroxide (H₂O₂) was able to efficiently weaken ECL-1 but strengthen ECL-2. When organophosphorus pesticides (OPs) were absent, the immobilized acetylcholinesterase-choline oxidase (AChE-ChOx) would catalyze the substrate acetylthiocholine chloride (ATCl) to produce H₂O₂, resulting in a quenched ECL-1 and an enhanced ECL-2. With the introduction of OPs, ECL-1 increased while ECL-2 accordingly decreased as OPs prohibited production of H₂O₂ by inhibiting activity of AChE. Highly sensitive ECL ratio detection for OPs was realized based on the change of the ratio of two signals. The dual anode emission properties of PFN NPs coupled with the opposite regulation of H₂O₂ on the two signals paved a new avenue for potentially tunable ECL ratio sensing strategy, and showed enormous potential applications for OPs analysis.

[Safety and efficacy evaluation of laparoscopic and open hepatectomy for hepatolithiasis: a propensity score matched analysis]

Objective: To compare the safety and efficacy of laparoscopic and open hepatectomy for hepatolithiasis. Methods: Between January 2014 and May 2020, the clinicopathological data of 254 patients with hepatolithiasis who underwent laparoscopic or open hepatectomy at the First Department of Hepatobiliary Surgery,Affiliated Hospital of North Sichuan Medical College were collected retrospectively. There were 74 males and 180 females with age of (56±8) years (range: 38 to 77 years). Of the 254 patients, 162 underwent laparoscopic surgery (laparoscopic group) and 92 underwent open surgery (open group). Propensity score matching(PSM) was performed to match baseline characteristics of the two groups,and then the perioperative results and follow-up efficacy were compared between the two groups. The t-test, Mann-Whitney U test, χ² test or Fisher's exact probability method was used to compare the perioperative data and follow-up results of the two groups after matching, respectively. Results: Each group had 63 patients after PSM with well-balanced baseline characteristics. There was no statistic difference in the type of hepatectomy,combined common bile duct exploration rate,T tube drainage placement rate,operation time,intraoperative transfusion rate,intraoperative accidental injury rate,initial and final stone clearance rate,and stone recurrence rate between the two groups. However,compared with the open hepatectomy group, the laparoscopic group had significantly lower intraoperative blood loss (M(IQR))(300(175)ml vs. 350(145)ml, Z=3.227,P=0.001),shorter postoperative hospital stay((10.6±4.1)days vs. (14.0±4.0)days,t=4.634,P<0.01),shorter time to postoperative oral intake ((1.8±1.1)days vs. (2.9±1.6)days, t=4.556, P<0.01), and lower postoperative complication rate (25.4%(16/63) vs. 49.2%(31/63), χ²=7.635, P=0.006). Conclusion: Laparoscopic hepatectomy is safe and effective for hepatolithiasis with the advantages of less intraoperative blood loss,lower postoperative complications and faster postoperative recovery.

Dynamic 3D DNA Rolling Walkers via Directional Movement on a Lipid Bilayer Supported by Au@Fe3O4 Nanoparticles for Sensitive Detection of MiRNA-16

Currently reported polyfluorene-based fluorescence detection usually shows high background signal and low detection sensitivity. This work developed a novel three-dimensional (3D) DNA rolling walker via directional movement on a lipid bilayer (LB) supported by Au@Fe₃O₄ nanoparticles (NPs) in a polyfluorene-based fluorescence system so that it could achieve significantly improved detection sensitivity and almost zero-background signal detection for miRNA-16. First, the carboxyl-functionalized poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(1,4-benzo-{2,1',3}-thiadazole)] polymer nanoparticles (c-PFBT PNPs) covalently bonded with amino-labeled single-strand CP and further hybridized with single-strand AP to prepare AP-CP-coupled c-PFBT PNP probes. Meanwhile, Au@Fe₃O₄ NPs were developed as efficient fluorescence quenchers and served as the matrix for assembling the LB. The resulting Au@Fe₃O₄@LB assembled cholesterol-labeled orbital DNA L1 and L2 and further assembled hairpins H1 and AP-CP-coupled c-PFBT PNP probes to construct DNA nanomachines. Then, the target miRNA-16 was introduced to initiate the rolling circle amplification (RCA) reaction and form dynamic DNA rolling walkers, thus releasing single-strand CP-coupled c-PFBT PNP probes. The magnetic separation effect of Au@Fe₃O₄ NPs made it possible to detect the fluorescence signal from the released probes, thus achieving almost zero-background signal detection for miRNA-16 with a low detection limit of 95 aM. The flexible interfaces provided by the LB endowed the DNA rolling walkers with high binding efficiency and low derailment probability, thus achieving significantly improved detection sensitivity. The developed strategy provided an attractive polyfluorene-based fluorescence platform with high-sensitivity and low-background signals.

Solvent-free synthesis of oleic acid-based wax esters using recyclable acidic deep eutectic solvent

Wax esters have been widely used in cosmetics and pharmaceutical products. Oleic acid wax esters can be used to replace spermaceti oil or jojoba oil. In this work, the acidic deep eutectic solvent (DES) composed of choline chloride and p-toluenesulfonic acid (1:4, mol/mol) was used as an efficient recyclable catalyst for the synthesis of oleic acid-based liquid wax esters through an esterification reaction. The esterification conversion of cetyl alcohol reached 99.1% under the following optimal reaction conditions: 5% DES as catalyst, molar ratio of fatty acid to alcohol of 1.3:1 and reaction temperature of 70 oC for 3h. The catalyst recovery experiments showed that this low-price acidic DES catalyst could be reused five times with uniform activity. Moreover, DES-catalyzed solvent-free esterification could be applied in the preparation of other oleic acid-based wax esters and excellent conversions (> 96%) could be obtained under such mild conditions.

Dlx3 Ubiquitination by Nuclear Mdm2 Is Essential for Dentinogenesis in Mice

Dentin is a major mineralized component of teeth. Odontoblasts are responsible for synthesis and secretion of dentin matrix. Previously, it has been demonstrated in a cell culture system that the E3 ubiquitin ligase, murine double minute 2 (Mdm2), promotes odontoblast-like differentiation of mouse dental papilla cells (mDPCs) by ubiquitinating p53 and the odontoblast-specific substrate Dlx3. However, whether Mdm2 plays an essential role in vivo in odontoblast differentiation and dentin formation remains unknown. In this study, we investigated the in vivo functions of Mdm2 using Dmp1-Cre;Mdm2 flox/flox mice combined with multiple histological and molecular biological methods. The results showed that Mdm2 deletion in the odontoblast layer led to defects in odontoblast differentiation and dentin formation. Unexpectedly, specific inhibition of the Mdm2-p53 axis in wild-type mice by injection of a small-molecule inhibitor Nutlin-3a indicated that the role of Mdm2 in dentinogenesis was p53 independent, which was inconsistent with the previous in vitro study. In situ proximity ligation assay (PLA) showed that Mdm2 interacted with and ubiquitinated Dlx3 in the odontoblast nucleus of mouse molars. Dlx3 promoted the translocation of Mdm2 to the nucleus, and in turn, the nuclear Mdm2 mediated ubiquitination of Dlx3 and promoted the odontoblast-like differentiation of mDPCs. Dlx3 interacted with Mdm2 through its C-terminal domain. Deletion of the C-terminal domain of Dlx3 reversed the enhanced odontoblast-like differentiation and the activation of Dspp promoter mediated by overexpression of wild-type or nuclear Mdm2. Our findings suggest that nuclear Mdm2 mediates ubiquitination of the transcription factor Dlx3, which is essential for Dlx3 transcriptional activity on Dspp as well as subsequent odontoblast differentiation and dentin formation.

TRPM7 Elicits Proliferation and Differentiation of Human Lens Epithelial Cells through the TGF-β/Smad Pathways

Epithelial-mesenchymal transition (EMT) plays a crucial role in the development of cataract. This study aimed to explore the effects of TRPM7 on the proliferation and differentiation of human lens epithelial cells. TRPM7 was over-expressed in LECs treated with TGF-β2. Down-regulation of TRPM7 attenuated the increase in cell viability and cell proliferation induced by TGF-β2. The LEC migration induced by TGF-β2 was also repressed by down-regulation of TRPM7. Epithelial-specific protein E-cadherin was up-regulated through knock-down of TRPM7. EMT-specific proteins, α-SMA, fibronectin and vimentin, were down-regulated through knockdown of TRPM7. Moreover, phosphorylation of Smad2 and Smad3 was also prevented by inhibition of TRPM7. Therefore, TRPM7 elicited LEC proliferation and EMT through enhancing activation of the TGF-β/Smad pathways, implying a new therapeutic target for cataract.

[Related factors for hyperkalemia and its recurrence in maintenance hemodialysis patients]

Objective: To investigate the prevalence of hyperkalemia and recurrent hyperkalemia in maintenance hemodialysis patients, and identify the related factors. Methods: The general information and clinical data of maintenance hemodialysis patients in the hemodialysis center of the First Affiliated Hospital of Nanjing Medical University from January to December 2020 were collected. According to the level of serum potassium, the patients were divided into normokalemia group and hyperkalemia group. Patients in the hyperkalemia group were further divided into single hyperkalemia group and recurrent hyperkalemia group according to the number of occurrences of hyperkalemia. Then, the prevalence of different serum potassium abnormalities and the related factors were explored. Results: Among the 352 patients included in the final analysis, 129 cases (36.6%) were in the normokalemia group [mean age: (62±15) years, 99 males] and 223 cases (63.4%) were in the hyperkalemia group [mean age: (60±14) years, 153 males]. Multivariate logistic regression analysis demonstrated that, compared with the normokalemia group, night-time dialysis (OR=4.012, 95%CI: 1.519-10.601, P=0.005), concurrent diabetes (OR=1.947, 95%CI: 1.148-3.304, P=0.013) and the number of serum potassium tested before hemodialysis (OR=1.561, 95%CI:1.292-1.885, P<0.001) were independent risk factors for hyperkalemia. Among 223 patients with hyperkalemia, 78 cases (35.0%) were in single hyperkalemia group and 145 cases (65.0%) were in recurrent hyperkalemia group. Multivariate logistic regression analysis demonstrated that, serum calcium (OR=21.885, 95%CI: 3.740-128.077, P=0.001), peak value of serum potassium before hemodialysis (OR=63.157, 95%CI: 25.265-157.876, P<0.001) and the number of serum potassium tested before hemodialysis (OR=1.814, 95%CI: 1.378-2.388, P<0.001) were the independent risk factors for the recurrence of hyperkalemia. Conclusions: The prevalence of hyperkalemia is high in maintenance hemodialysis patients, especially in those with diabetes or night-time dialysis. It is necessary to monitor serum potassium regularly. In addition, high serum calcium and peak value of serum potassium before hemodialysis are related factors for recurrent hyperkalemia.

[Exploration and practice of periodontal specialist training system]

The standardized training of specialist doctors is an important part of medical education after graduation and it is the only way to train clinicians to diagnose and treat the specialist diseases independently by using a standardized and high-quality way. The prevalence of periodontal disease and the proportion of patienets with severe and advanced periodontitis in our country are high and the diagnosis and treatment process for the periodontal disease are complicated. There is an urgent need to expand the team of periodontal specialists capable of the specialized treatment. The training of periodontal specialists in our country has just started. The present article summarizes the exploration and practice of periodontal specialist training in Peking University School and Hospital of Stomatology in the past five years, including the establishment of training bases, formulation of clear training goals, strict implementation of training rules, strengthening of process quality control to ensure the trainees could reach the expected standard of periodontal specialist after training. Through the summary of the previous stage practice, the authors hope to explore and establish a periodontal specialist training system in line with our country's national conditions and further to promote and accelerate the pace of nationwide periodontal specialist training system.

The detection of SAS1B in serum provides clues for early diagnosis of thyroid cancer

OBJECTIVE

The incidence of thyroid cancer is rising globally. Most patients progress slowly, but some patients develop lymph node and distant metastasis earlier, and their prognosis is poor. Therefore, early diagnosis and warning of malignancy are very meaningful for such patients. SAS1B gene is a newly discovered protein expressed on the surface of mature egg cells and has metalloendopeptidase activity. We aimed at exploring whether SAS1B is involved in the occurrence of thyroid cancer, and at providing evidence for early diagnosis and targeted therapy of thyroid cancer.

PATIENTS AND METHODS

In this study, a rabbit anti-human SAS1B polyclonal antibody was prepared by gene recombination technology. The indirect ELISA method was used to detect the SAS1B protein expression in the serum of 69 patients with thyroid cancer and 55 normal controls, and the relevant pathological factors were analyzed. Immunohistochemistry and PCR technology were used to investigate the expression levels of SAS1B protein and mRNA in 30 thyroid cancer tissues and 23 control thyroid tissues.

RESULTS

The titer of SAS1B recombinant antibody was 1:51200. The expression of SAS1B in the serum of patients with thyroid cancer was higher than that in the normal control group (p<0.01). The antibody had a good sensitivity in serum detection of cancer patients (p=0.008<0.01), the linear regression analysis result was that the expression of SAS1B gene was related to tumor envelope invasion and lymph node metastasis (p=0.003<0.01, p=0.003<0.01), and it was irrelevant to the patient's gender, age, tumor mass size, number of cancer foci, pathological stage, etc. (p>0.05). The results of immunohistochemistry showed that SAS1B protein was mainly located in the cytoplasm and membrane of thyroid cancer cells. The expression intensity in thyroid cancer tissues was higher than that in control tissues (p<0.05), but it was not expressed in normal thyroid tissues. Antibodies showed a good sensitivity that was used to detect thyroid cancer tissues (p=0.000<0.01). The results of ordinary PCR detection using thyroid cancer tissue and control thyroid tissue showed that the amplification products of the three domains (N-terminal, C-terminal and catalytic domain) of the SAS1B gene showed high expression in thyroid cancer tissue. q-PCR results showed that the expression of SAS1B gene in thyroid cancer and control thyroid tissue was higher than that in control group (p<0.05), and the genes of Aurora A and BARD1 related to centrosome replication and DNA replication forks protection during the proliferation were highly expressed in thyroid cancer tissue. The study results suggested that SAS1B was involved in the carcinogenesis of thyroid cancer. The Hum_mPLoc.2.0 software, PSORT Ⅱ software and UniProt software were used to predict that SAS1B protein had secretory protein properties.

CONCLUSIONS

The above data indicate that the SAS1B gene is closely related to the process of thyroid cancer and can serve as a good tumor marker that can be used for early diagnosis and early warning of thyroid malignancy.