Instrument separation is a critical complication during root canal therapy, impacting treatment success and long-term tooth preservation. The etiology of instrument separation is multifactorial, involving the intricate anatomy of the root canal system, instrument-related factors, and instrumentation techniques. Instrument separation can hinder thorough cleaning, shaping, and obturation of the root canal, posing challenges to successful treatment outcomes. Although retrieval of separated instrument is often feasible, it carries risks including perforation, excessive removal of tooth structure and root fractures. Effective management of separated instruments requires a comprehensive understanding of the contributing factors, meticulous preoperative assessment, and precise evaluation of the retrieval difficulty. The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes. The current manuscript provides a framework for understanding the causes, risk factors, and clinical management principles of instrument separation. By integrating effective strategies, endodontists can enhance decision-making, improve endodontic treatment success and ensure the preservation of natural dentition.
Humans ; Root Canal Therapy/adverse effects* ; Consensus ; Root Canal Preparation/adverse effects*

The important studies in the field of extracorporeal life support (ECLS) in 2024 focused on the application of cardiac support technologies in acute myocardial infarction (AMI) with cardiogenic shock (CS): veno-arterial extracorporeal membrane oxygenation (V-A ECMO) has not shown advantages in either short- or long-term outcomes and may increase the risk of bleeding and vascular complications; in contrast, micro-axial flow pumps demonstrate potential in improving mortality. The effects of veno-venous extracorporeal membrane oxygenation (V-V ECMO) combined with prone positioning on severe acute respiratory distress syndrome (ARDS) remain uncertain. The survival benefit of extracorporeal cardiopulmonary resuscitation (ECPR) in out-of-hospital cardiac arrest (OHCA) patients has been further validated. The potential benefits of extracorporeal carbon dioxide removal (ECCO2R) require further investigation. Additionally, new guidelines released in 2024 focus on Neurological monitoring and management during ECMO, as well as the Definition and management of right ventricular injury during veno-venous ECMO. ECMO management requires more refined strategies, including optimized oxygenation targets, anticoagulation, blood transfusion, and weaning strategies to improve patient outcomes.
Humans ; Extracorporeal Membrane Oxygenation/methods* ; Shock, Cardiogenic/therapy* ; Cardiopulmonary Resuscitation ; Myocardial Infarction/therapy*

Objective:To investigate the role and related mechanisms of the LiaSR two-component system in acid tolerance and biofilm formation abilities of Streptococcus mutans (Sm) 593. Methods:The growth curves of various Sm strains in pH=5.5 brian heart infusion (BHI) medium were analyzed. And colony forming unit (CFU) was also performed to evaluate the acid tolerance of Sm. Laurdan probe, H +-K +adenosine triphosphate (ATP)ase activity analysis kit, proton permeability assay and real-time fluorescence quantitative PCR (RT-qPCR) were conducted to detect the acid tolerant mechanisms of LiaSR two-component system in Sm. Crystal violet staining, CFU, SYTOX probe and anthrone-sulfuric method were used to analyze the properties and structures of the Sm biofilms. RT-qPCR was conducted to detect the expression levels of underlying regulated genes. Results:The growth of mutants in acidic BHI were inhibited ( P<0.05). The acid tolerance of mutants significantly decreased compared to the wild-type strain ( P<0.05). In mutants, the activity of H +-ATPase (917.06±59.53 and 469.53±47.65) were elevated by 7.22-folds and 3.70-folds compared to the wild-type strain (127.00±50.71) ( P<0.001, P<0.001) and the encoded gene atpD (3.39±0.21 and 1.94±0.17) were also elevated by 3.39-folds and 1.94-folds compared to the wild-type strain (1.00±0.15) ( P<0.001, P=0.001). The Laurdan generalized polarization of mutants (0.18±0.04 and 0.18±0.05) increased significantly compared to the wild-type strain (0.08±0.05) ( P=0.006, P=0.003) and the expression levels of fabM gene were decreased in mutants (0.52±0.11 and 0.57±0.05) by 1/2 ( P=0.014, P=0.022). In liaR deletion mutant, the reduced terminal pH (4.76±0.01) can also be observed ( P<0.001). The total amount of the biofilms of three Sm didn't show significant differences ( P>0.05). But the number of viable bacteria of mutants′ biofilms were decreased [Sm 593: (12.00±2.80)×10 7 CFU/ml; Sm ΔliaS: (2.95±1.13)×10 7 CFU/ml; Sm ΔliaR: (7.25±1.60)×10 7 CFU/ml] ( P=0.001, P=0.024). The extracellular DNA were increased by 18.00-folds and 6.50-folds in mutants′ biofilms (128.73±15.65 and 46.38±5.52) compared to the wild-type strain (7.16±3.62) ( P<0.001, P=0.003). Water-soluble exopolysaccharides could be found up-regulated in liaS deletion mutant [(138.73±10.12) μg/ml] ( P=0.003) along with the expression level of gtfC gene (1.65±0.39) ( P=0.014). The expression level of gtfD were elevated by 47.43-folds and 16.90-folds in mutants ( P<0.001, P=0.010). Conclusions:The LiaSR two-component system can promote the expression of fabM gene and increase the fluidity of Sm which contributes to acid tolerance. The LiaR can also decrease the proton permeability and restrict the entrance of H +. The LiaSR two-component system can negatively regulate the production of the extracellular matrix in Sm biofilm.

OBJECTIVE To characterize paclitaxel nanoparticles （PTX-PLGA-NPs） and evaluate their in vitro inhibitory effect on Lewis lung cancer cells. METHODS The PTX-PLGA-NPs prepared by the emulsion-solvent evaporation method were characterized in terms of particle size， polydispersity index （PDI）， Zeta potential， microscopic morphology， encapsulation efficiency， drug loading， ultraviolet-visible absorption characteristics and stability. Using mouse Lewis lung cancer cells as the subjects and paclitaxel reference substance as the control， the cytotoxicity and in vitro killing activity of PTX-PLGA-NPs were detected using CCK-8 method and Calcein-AM/PI double staining method， respectively. The effects of PTX-PLGA-NPs on cell apoptosis and cell cycle were assessed by Annexin Ⅴ-FITC/PI staining method and PI staining method， respectively. RESULTS PTX-PLGA-NPs were spherical with an average particle size of （172.03±0.95） nm， PDI of 0.098±0.012， and Zeta potential of （－1.76±0.02） mV. The encapsulation efficiency and drug loading were （52.32±0.66）% and （7.07±0.18）%， respectively， and the ultraviolet-visible absorption characteristics were not affected by the carrier polylactic-co-glycolic acid. When stored in the dark at 4 °C for 7 days， no significant change was noted in particle size， and the average PDI （after 1， 2， 4 and 7 days of storage） was under 0.3. Compared with the paclitaxel reference substance group， the PTX-PLGA-NPs group had more cells in a state of death， the survival rate （at the PTX concentration of 11.2 μg/mL） was significantly decreased， and both the apoptosis rate and the proportion of G2 phase cells were significantly increased （P＜0.05）. CONCLUSIONS The prepared PTX-PLGA-NPs indicate homogeneity in particle size， uniform dispersion， stable properties， and stronger in vitro killing effect on lung cancer cells than PTX.

Objective:To explore the clinical and genetic characteristics of three children with Leguis syndrome.Methods:Three children suspected as Legius syndrome at the Henan Children′s Hospital for precocious puberty or short stature from June 6, 2019 to August 25, 2022 were selected as the study subjects. Clinical data of the children were collected. All children were subjected to whole exome sequencing, and candidate variants were verified by Sanger sequencing.Results:All of the children (including 2 females and 1 male, and aged 4 years and 6 months, 8 years, and 14 years and 8 months, respectively) had typical café de lait spots. Child 1 also had precocious puberty, and children 2 and 3 had short statures. Genetic testing revealed that all of them had harbored heterozygous variants of the SPRED1 gene, including c. 751C>T (p.Arg251Ter194) in child 1, c. 229A>T (p.Lys77Ter368) in child 2, and c. 1044_1046delinsC (p.R349fs *11) in child 3. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the c. 751C>T (p.Arg251Ter194) variant was predicted to be likely pathogenic, whilst the other two were known pathogenic variants. Conclusion:All of the three children were diagnosed with Leguis syndrome due to variants of the SPRED1 gene, which had manifested as multiple café de lait spots in conjunct with precocious puberty or short statures.

ObjectiveTo compare the effects of different doses and withdrawal time of 4-vinylcyclohexene diepoxide （VCD） on the reproductive endocrine levels of female rats， and to explore the effective， stable， and safe dosage of VCD for constructing a premature ovarian insufficiency （POI） rat model. MethodSD rats with regular estrous cycles were randomly divided into three groups： blank group， low-dose VCD group （80 mg·kg^-1·d^-1）， and high-dose VCD group （160 mg·kg^-1·d^-1）， with 24 rats in each group. After drug intervention， samples were collected on the 15th day （D15） and the 45th day （D45） after intervention. The general condition， rate of estrous cycle disturbance， serum hormone levels， ovarian histomorphology， follicle count， pregnancy outcome， and the protein and mRNA expression of transforming growth factor （TGF）-β and Smad2/3 were assessed. ResultCompared with the blank group， the low-dose VCD group showed no significant differences in the rate of estrous cycle disturbance or serum follicle-stimulating hormone （FSH）， luteinizing hormone （LH）， and estradiol （E₂） levels. Ovarian tissue was damaged. Specifically， the number of primordial and primary follicles decreased on D15 （P<0.01）， and the number of secondary follicles （P<0.01） and antral follicles （P<0.05） further decreased on D45. The litter number decreased on D15 （P<0.05）， but there was no significant difference on D45. Furthermore， TGF-β protein levels increased on D15 （P<0.05） and D45 （P<0.01）. The Smad2/3 levels increased on D45 （P<0.01）， and TGF-β and Smad2/3 mRNA levels increased on D45 （P<0.05）. Compared with the results in the blank group， the disturbance rate of the estrous cycle increased on D45 in the high-dose VCD group （P<0.01）. The serum of FSH and LH increased （P<0.01）， while E₂ decreased （P<0.05）. Ovarian tissue was damaged， and the downward trend of follicles at all levels was similar to that in the low-dose VCD group. The litter number significantly decreased on D15 and D45. TGF-β and Smad2/3 protein levels increased （P<0.05，P<0.01）， and TGF-β mRNA increased on D45 （P<0.05）. ConclusionHigh-dose VCD is an ideal method for constructing a POI rat model， being effective， stable， and safe.

Fear memory contextualization is critical for selecting adaptive behavior to survive. Contextual fear conditioning (CFC) is a classical model for elucidating related underlying neuronal circuits. The primary visual cortex (V1) is the primary cortical region for contextual visual inputs, but its role in CFC is poorly understood. Here, our experiments demonstrated that bilateral inactivation of V1 in mice impaired CFC retrieval, and both CFC learning and extinction increased the turnover rate of axonal boutons in V1. The frequency of neuronal Ca²⁺ activity decreased after CFC learning, while CFC extinction reversed the decrease and raised it to the naïve level. Contrary to control mice, the frequency of neuronal Ca²⁺ activity increased after CFC learning in microglia-depleted mice and was maintained after CFC extinction, indicating that microglial depletion alters CFC learning and the frequency response pattern of extinction-induced Ca²⁺ activity. These findings reveal a critical role of microglia in neocortical information processing in V1, and suggest potential approaches for cellular-based manipulation of acquired fear memory.
Mice ; Animals ; Primary Visual Cortex ; Extinction, Psychological/physiology* ; Learning/physiology* ; Fear/physiology* ; Hippocampus/physiology*

OBJECTIVE To investigate the clinical efficacy and safety of rituximab （RTX） followed by belimumab （BLM） in patients with severe systemic lupus erythematosus（SSLE）. METHODS Nine SSLE patients， who were treated with RTX followed by BLM for more than 6 months in the Department of Rheumatology and Immunology of the First Affiliated Hospital of Zhengzhou University from October 2020 to June 2021， were enrolled. Baseline clinical data of patients， laboratory examination results and basic treatment status at weeks 0， 4， 12， and 24 of medication were collected retrospectively. The patients’ systemic lupus erythematosus disease activity index （SLEDAI） score， glucocorticoid dosage and serological indicators （complement C3， complement C4， serum albumin， and 24-hour urine protein quantification） level were analyzed. At the same time， the occurrence of adverse drug reaction was collected. RESULTS All 9 patients completed more than 24 weeks of RTX followed by BLM therapy. All patients suffered from renal impairment， of which 7 （77.8%） had renal pathology support， 3（33.3%） had blood system damage and 2 （22.2%） had nervous system damage. During treatment， with the prolongation of treatment time， the SLEDAI score， 24- hour urinary protein quantification， and glucocorticoid dosage of patients showed a significant downward trend， and ultimately decreased to the normal index level （P＜0.05）； serum albumin， complement C3 and complement C4 all showed a significant upward trend， eventually rose to the normal index level （P＜0.05）. During treatment and follow-up， 1 patient developed herpes zoster， 1 patient developed upper respiratory tract virus infection， and 1 patient developed urinary system bacterial infection. All patients recovered after symptomatic treatment. CONCLUSIONS In sequential use of RTX followed by BLM for SSLE， early administration of RTX can quickly stabilizethe condition， significantly alleviate clinical symptoms， and gradually normalize specific serological indicators； subsequent administration of BLM can reduce the type and dosage of basic treatment drugs； there is no increase in the incidence of adverse drug reactions.

Objective:To analyze the fail mode of neoadjuvant therapy combined with surgery for locally advanced esophageal squamous cell carcinoma (ESCC) after long-term follow-up.Methods:Clinical data of consecutive 238 patients with locally advanced resectable ESCC who underwent neoadjuvant therapy combined with surgery in Zhejiang Cancer Hospital from September 2012 to October 2019 were retrospectively analyzed. The failure mode in the whole cohort was analyzed after long-term follow-up. The overall survival (OS) and disease free survival (DFS) rates were analyzed by Kaplan-Meier method. Survival differences were determined by log-rank test.Results:The pathological complete response (pCR) rate was 42.0% in 238 patients. After a median follow-up of 46.1 months, tumor progression occurred in 96 patients (40.3%), including 25 patients (10.5%) with local recurrence, 61 patients (25.6%) with distant metastases, and 10 patients (4.2%) with simultaneous local recurrence and distant metastases. The median OS and DFS were 64.7 months and 49.9 months. And the 3-, 5-, and 7-year OS and DFS rates were 70.0%, 52.8%, 36.4% and 63.5%, 42.5%, and 30.0%, respectively. The 3-, 5-, and 7-year locoregional recurrence-free survival rates and distant metastasis-free survival rates were 86.0%, 71.4%, 61.2% and 70.6%, 55.9%, 43.0%. Compared with non-pCR patients, the overall progression rate and distant metastasis rate of pCR patients were lower (26.0% vs. 50.7%, 16.0% vs. 32.6%, both P<0.05). And the 3-, 5-, and 7-year OS (83.0% vs. 60.2%, 69.7% vs. 41.7%, 50.4% vs. 27.7%, all P<0.001) and DFS rates (80.4% vs. 51.4%, 63.9% vs. 31.2%, 45.9% vs. 20.3%, all P<0.001) were significantly better in pCR patients. Conclusions:Distant metastasis is the main failure mode of patients with locally advanced ESCC after neoadjuvant therapy. Patients with postoperative pCR can achieve better long-term survival.

The rapid progress on immunotherapy and targeted therapy has brought long-term survival benefits for locally advanced non-small cell lung cancer (NSCLC). The oncology community has also paid more attention to the local treatment for advanced NSCLC, especially for patients with limited metastatic lesions, also known as oligo-metastasis. Many studies have reported that oligo-metastatic NSCLC patients could benefit from the combination of local and systematic treatment, and even to be cured. In recent years, with the advances in radiation technology, stereotactic body radiation therapy (SBRT) has achieved precise high-dose radiotherapy for small target tumors. Currently, SBRT has been widely applied in the treatment of inoperable early lung cancer, and its application value and safety in patients with advanced lung cancer are also being actively explored. In this article, the research status, progress and future development direction of SBRT in the treatment of oligo-metastatic NSCLC were discussed.