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*

OBJECTIVE: To evaluate the effect and safety of Chinese medicine (CM) Fuzheng Huazhuo Decoction (FHD) in treating patients with coronavirus disease 2019 (COVID-19) who persistently tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: This retrospective cohort study was conducted at Shanghai New International Expo Center shelter hospital in China between April 1 and May 30, 2022. Patients diagnosed as COVID-19 with persistently positive SARS-CoV-2 reverse transcription-polymerase chain reaction (RT-PCR) test results for ⩾8 days after diagnosis were enrolled. Patients in the control group received conventional Western medicine (WM) treatment, while those in the FHD group received conventional WM plus FHD for at least 3 days. The primary outcome was viral clearance time. Secondary outcomes included negative conversion rate within 14 days, length of hospital stay, cycle threshold (Ct) values of the open reading frame 1ab (ORF1ab) and nucleocapsid protein (N) genes, and incidence of new-onset symptoms during hospitalization. Adverse events (AEs) that occurred during the study period were recorded. RESULTS: A total of 1,765 eligible patients were enrolled in this study (546 in the FHD group and 1,219 in the control group). Compared with the control group, patients receiving FHD treatment showed shorter viral clearance time for nucleic acids [hazard ratio (HR): 1.500, 95% confidence interval (CI): 1.353-1.664, P<0.001] and hospital stays (HR: 1.371, 95% CI: 1.238-1.519, P<0.001), and a higher negative conversion rate within 14 days (96.2% vs. 82.6%, P<0.001). The incidence of new-onset symptoms was 59.5% in the FHD group, similar to 57.8% in the control group (P>0.05). The Ct values of ORF1ab and N genes increased more rapidly over time in the FHD group than those in the control group post-randomization (ORF1ab gene: β =0.436±0.053, P<0.001; N gene: β =0.415 ±0.053, P<0.001). The incidence of AEs in the FHD group was lower than that in the control group (24.2% vs. 35.4%, P<0.001). No serious AEs were observed. CONCLUSION FHD was effective and safe for patients with persistently positive SARS-CoV-2 PCR tests. (Registration No. ChiCTR2200063956).
Humans ; Drugs, Chinese Herbal/adverse effects* ; Retrospective Studies ; Male ; Female ; Middle Aged ; COVID-19 Drug Treatment ; SARS-CoV-2/drug effects* ; COVID-19/virology* ; Adult ; Aged ; Treatment Outcome

Objective To establish a stable,reliable,and clinically relevant porcine model of endotoxin-induced acute respiratory distress syndrome(ARDS).Methods Ten 8-month-old male Bama minipigs were deeply sedated,followed by invasive mechanical ventilation and electrocardiographic monitoring.Lipopolysaccharide(LPS)was intravenously pumped at 600 μg/(kg·h)for 3 hours,then maintained at 15 μg/(kg·h)thereafter.Dynamic monitoring was performed at five time points after LPS injection(LPS 0,1,3,5,and 8 h),including arterial blood gas analysis and chest computed tomography(CT)scans.Pathological examination of lung tissues obtained via bronchoscopic biopsy(HE staining and transmission electron microscopy)was conducted.These indicators were comprehensively used to evaluate the success of the animal model.Results At 5 hours after LPS administration,8 minipigs developed symptoms such as skin cyanosis,elevated body temperature,and respiratory distress.The oxygenation index decreased to<300 mmHg.Chest CT scans showed diffuse pulmonary infiltrates.Histopathology revealed alveolar edema and hyaline membrane formation.Transmission electron microscopy demonstrated disruption of pulmonary blood-air barrier,depletion of lamellar bodies in type Ⅱ pneumocytes,inflammatory cell infiltration,and exudation of plasma proteins and fibrin.Compared with LPS 0 h,at LPS 8 h,the oxygenation index and arterial blood pH were significantly decreased(P<0.001),while blood lactic acid and serum potassium were significantly increased(P<0.05);serum calcium and base excess were significantly decreased(P<0.05),and the lung injury score based on HE-stained lung sections was significantly increased(P<0.01).Conclusion The porcine ARDS model established by continuous LPS injection can dynamically simulate the pathophysiological characteristics and typical pathological manifestations of clinical septic ARDS,making it an effective tool to study the pathogenesis,prevention,and treatment strategies of septic ARDS.

Objective To investigate the effect of up-regulating tumor necrosis factor alpha induced protein 3(TNFAIP3)expression on hippocampal neurons in mice with cerebral ischemia-reperfusion.Methods The mice were randomly divided into 6 groups:sham group,sham empty vector group(sham-),sham TNFAIP3 high expression group(sham+),model group,model empty vector group(model-),model TNFAIP3 high expression group(model+).A mouse model of middle cerebral artery occlusion and cerebral ischemia-reperfusion was established using the suture method.After the successful establishment of the model,lentivirus was injected into the hippocampus 24 hours later.Two weeks later,samples were collected and Western blotting was used to detect the expressions of TNFAIP3 and ERK signaling pathway proteins.The changes in ischemic area were observed by 2,3,5-triphenyltetrazolium chloride(TTC)staining;HE staining was used to observe the morphological changes of hippocampal neurons,and ELISA was used to detect the expressions of lipoprotein-associated phospholipase A2(Lp-PLA2)and interleukin(IL)-8.Results The results of Western blotting indicated that the TNFAIP3 expression in the model group decreased significantly compared with the sham group(P＜0.05);Compared with the model group,there was no significant change in TNFAIP3 expression in the model-group(P＞0.05);The TNFAIP3 expression in the model+group increased significantly compared with the model group and model-group(P＜0.05).Compared with the sham group,the results of the sham+group showed that the ischemic area had no significant changes in TTC staining,and there were no significant changes in hippocampal neuronal morphology,and the expressions ERK signaling pathway proteins,Lp-PLA2 and IL-8(P＞0.05);Compared with the sham-and sham+groups,the model group showed an increase in ischemic area,significant damage to hippocampal neurons,a decrease in the number of Nissl bodies,and a significant increase in the expressions of ERK signaling pathway proteins,Lp-PLA2,and IL-8(P＜0.05);Compared to the model-group,the model+group showed a decrease in ischemic area,an increase in the number of neurons in the hippocampus and the number of Nissl bodies,and a significant decrease in the expressions of ERK signaling pathway proteins,Lp-PLA2,and IL-8(P＜0.05).Conclusion Up-regulation of TNFAIP3 may be one of the methods for repairing hippocampal neuronal damage caused by cerebral ischemia reperfusion.

Objective:To investigate the regulative effects of Streptococcus mutans (Sm) antisense vicK RNA (ASvicK) on the multi-species biofilm formed by three common oral streptococci (Sm, Streptococcus sanguinis, and Streptococcus gordonii) (Sm+Ss+Sg). Methods:ASvicK over-expression strain was constructed by using a recombinant plasmid, and three-species biofilm UA159+Ss+Sg and ASvicK+Ss+Sg were cultured. The phenotypes of biofilms were detected by scanning electron microscopy (SEM). Crystal violet (CV) assay was used to detect biofilm biomass. Lactate kit and anthrone-sulfuric acid colorimetric assay were used to determine the abilities of lactic acid and exopolysaccharides production, respectively. The proportions of three-species and expression levels of the cariogenic-related genes in biofilms were detected by TaqMan fluorescence quantitative PCR and real-time fluorescence quantitative PCR. A biofilm demineralization model of human enamel slabs was further constructed, and the hardness of enamel surface was detected.Results:Compared to UA159+Ss+Sg, over-expression of ASvicK could inhibit biofilm formation and lactic acid production in ASvicK+Ss+Sg biofilm significantly decreased by 78.93% ( P<0.001) and 62.23% ( P<0.001), respectively. With ASvicK over-expression, the amounts of water-insoluble and-soluble glucoses in ASvicK+Ss+Sg biofilm were reduced respectively by 39.13% ( P<0.001) and 68.00% ( P<0.001). Compared to the UA159+Ss+Sg Group, the proportion of Sm, the cariogenic bacteria, showed 33.00% reduction ( P<0.01) in Sm+Ss+Sg biofilm, and the gene expressions of cariogenic-relative genes vicK/X, gtfB/C/D, and ftf significantly decreased ( P<0.05). The micro-hardness value of enamel slabs after demineralization by ASvicK+Ss+Sg biofilm was significantly increased to 183.84% ( P<0.001). Conclusions:ASvicK over-expression could reduce the Sm proportion and weaken the cariogenicity of oral Streptococcus biofilm, thereby possibly slowing down the progression of caries.

Objective To propose a Q factor-based fatigue vibration evaluation method of the ultrasonic knife tip.Methods Firstly,an ultrasonic cutter fatigue testing table was established to realize repeated cutting,which was composed of a power supply module,a three-axis moving module,an ultrasonic cutter clamping module and a control module.Secondly,10 ultrasonic knives of some brand underwent fatigue testing with the table,during which non-contact measurement of the ultrasonic knife tip vibration was carried out and the Q factors were calculated at the five periods of the fatigue test,including the periods before cutting,after 500 times of cutting,after 1 000 times of cutting,after 2 000 times of cutting and after 3 000 times of cutting.Finally,the average cutting speed and burst pressure for coagulated vessels were computed at each period to validata the effectiveness of the method proposed.Results It's indicated that Q factor could effectively reflect the fatigue degradation of the ultrasonic knife tip,while the average cutting speed and burst pressure for coagulated vessels were difficult to efficiently evaluate the fatigue degradation level of the ultrasonic knife tip due to the uncertainty factors in the measurement process.Conclusion The proposed Q factor-based evaluation method can directly evaluate fatigue vibration of the ultrasonic knife tip in an accurate and quantitative manner.[Chinese Medical Equipment Journal,2024,45(6):17-22]

Objective To carry out accurate quantative evaluation of MRI scanning noise based on laser vibrometry technology.Methods Skull and spine MRI was performed with mute and conventional sequences.A laser vibrometry device was used to sample the surface vibration noise at the outer edge of the inspection hole of MRI system according to GB/T 16539-1996 Acoustics—Determination of sound power levels of noise sources using vibration velocity—Measurement for seal machinery,and the indicators of sound power level,sound pressure level and perceived noise level obtained by the three calculation methods(LPN1,LPN2 and LPN3)were analyzed with some dedicated MRI noise analysis software.Results The peak sound pressure levels for conventional and mute sequences of skull scanning were 81 and 63 dB(A),respectively,and mute sequence reduced the noise level significantly;the peak sound pressure levels for conventional and mute sequences of spine scanning were 79 and 75 dB(A),respectively,and the noise reduction level was significantly lower than that of skull scanning.Significant differences in noise reduction were not found in spine scanning sequences,while were found in skull scanning sequences.During spine and skull scanning LPN1,LPN2 and LPN3 obtained by the three calculation methods of conventional and mute sequences were all higher than the overall sound power and overall pressure levels obviously.Conclusion Mute sequence can not realize linear noise reduction for the whole frequency band,the perceived noise of the human ear during MRI scanning is related directly to the scanning sequence,and there may be some bias when only one physical indicator is involved in the noise evaluation of MRI system.[Chinese Medical Equipment Journal,2024,45(10):20-24]

Objective:To analyze the effects of highdose methotrexate(HD-MTX)and lenalidomide as central nervous system(CNS)prophylaxis strategies in patients with diffuse large B-cell lymphoma(DLBCL).Methods:The data of DLBCL patients with high risk of CNS recurrence who were initially treated in Fujian Provincial Hospital and Fujian Cancer Hospital from January 2012 to June 2022 were analyzed retrospectively.The patients were divided into HD-MTX group and lenalidomide group according to different prophylaxis strategies.Each group was further divided into high-risk group and medium-risk group based on CNS-IPI score and/or testicular involvement.The CNS relapse-free survival(CRFS)rate,adverse effects,and the effects of different prophylaxis strategies on overall survival(OS)rate and progression-free survival(PFS)rate were evaluated in different groups and subgroups.Results:There were 200 patients enrolled in this study,80 cases in lenalidomide group and 120 cases in HD-MTX group.According to the delivery timing of prophylactic HD-MTX,the patients in HD-MTX group were further divided into two groups:80 cases at the end of induction chemotherapy and 40 cases during chemotherapy interval.At a median follow-up of 48(14-133)months,the 4-year CRFS rate,4-year PFS rate,and 4-year OS rate of the HD-MTX group was 93.6％,57.2％,and 68.8％,respectively,while that of the lenalidomide group was 90.4％,69.4％and 75.6％.There were no significant differences in 4-year CRFS rate,4-year PFS rate,and 4-year OS rate between HD-MTX group and lenalidomide group(all P＞0.05),but lenalidomide group showed a trend of improvement in PFS.Further subgroup analysis showed that there was no significant difference in 4-year CRFS rate between high-risk patients of the two groups(91.7％vs 83.4％,P＞0.05),while 4-year PFS rate showed difference(49.5％vs 64.2％,P＜0.05).A total of 248 cycles were collected for adverse reaction analysis in the HD-MTX group,and 25 cycles occurred neutropenia accompanied with infection(10.1％),while in lenalidomide group 240 cycles were collected in which 20 cycles occurred neutropenia accompanied with infection(8.3％).Both the two groups had no treatment-related deaths.Conclusion:Compared with HD-MTX,lenalidomide combined with immunochemotherapy can prevent CNS relapse,at the same time,improve prognosis,which is a safe and well tolerated central prophylaxis strategy.

Metabolic dysfunction-associated steatotic liver disease(MASLD)is the most prevalent chronic liver disease globally,with only one Food and Drug Administration(FDA)-approved drug for its treatment.Given MASLD's complex pathophysiology,ther-apies that simultaneously target multiple pathways are highly desirable.One promising approach is dual-modulation of the famesoid X receptor(FXR),which regulates lipid and bile acid metabolism.However,FXR agonists alone are insufficient due to their limited anti-inflammatory effects.This study aimed to dto identify natural products capable of both FXR activation and inflammation inhibition to provide a comprehensive therapeutic approach for MASLD.Potential FXR ligands from the Natural Product Library were predicted via virtual screening using the Protein Preparation Wizard module in Schrodinger(2018)for molecular docking.Direct binding and regulation of candidate compounds on FXR were analyzed using surface plasmon resonance(SPR)binding assay,reporter gene ana-lysis,and reverse transcription-polymerase chain reaction(RT-PCR).The anti-inflammatory properties of these compounds were eval-uated in AML12 cells treated with tumor necrosis factor-alpha(TNF-α).Dual-function compounds with FXR agonism and inflamma-tion inhibition were further identified in cells transfected with Fxr siRNA and treated with TNF-α.The effects of these dual-function compounds on lipid accumulation and inflammation were evaluated in cells treated with palmitic acid.Results revealed that 17 natural products were predicted via computational molecular docking as potential FXR agonists,with 15 exhibiting a strong affinity for FXR recombinant protein.Nine isoflavone compounds significantly enhanced FXR reporter luciferase activity and the mRNA expressions of Shp and Ostb.Structure-activity relationship analysis indicated that introducing isopropyl or methoxy groups at the C7 position or a methoxy group at the C6 position could enhance the agonistic efficacy of isoflavones.Three compounds(2,6,and 8)were identified as dual-function natural products functioning as FXR agonists and inflammatory inhibitors,while one compound(12)acted as an FXR agonist to inhibit inflammation.These natural products protected hepatocytes against palmitic acid-induced lipid accumulation and in-flammation.In conclusion,compounds 2,6,and 8(genistein,biochanin A,and 7-methoxyisoflavone,respectively)were identified as dual-function bioactive products that transactivate FXR and inhibit inflammation,serving as potential candidates or lead compounds for MASLD therapy.

OBJECTIVE: To assess the effect and safety of Reyanning Mixture (RYN) in treating asymptomatic or mild severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in children and adolescents. METHODS: This is a prospective, open-label, randomized controlled trial. Patients aged 1-17 years and diagnosed with asymptomatic or mild coronavirus disease-2019 (COVID-19) were assigned to an intervention group (RYN plus standard care) and a control group (standard care) according to a randomization list. The primary outcomes were SARS-CoV-2 negative conversion time. Secondary outcomes included negative conversion rate on days 3 and 7, hospital length of stay, symptom relief rate, new-onset symptoms of asymptomatic infected patients, and progressive disease rate. The cycle threshold (Ct) values of ORF1ab or N genes were also tested. RESULTS: A total of 214 patients in the intervention group and 217 in the control group were analyzed. The SARS-CoV-2 negative conversion time was significantly shortened in the intervention group [5 days (interquartile range (IQR): 5-6) vs. 7 days (IQR: 6-7), P<0.01]. By days 3 and 7, the negative conversion rates were significantly higher in the intervention group (day 3: 32.7% vs. 21.2%, P=0.007; day 7: 75.2% vs. 60.8%, P=0.001). Ct values significantly increase on day 2 [ORF1ab gene: 35.62 (IQR: 29.17-45.00) vs. 34.22 (IQR: 28.41-39.41), P=0.03; N gene: 34.97 (IQR: 28.50-45.00) vs. 33.51 (IQR: 27.70-38.25), P=0.024] and day 3 [ORF1ab gene: 38.00 (IQR: 32.72-45.00) vs. 35.81 (IQR: 29.96-45.00), P=0.003; N gene: 37.16 (IQR: 32.01-45.00) vs. 35.26 (IQR: 29.09-45.00), P=0.01]. No significant difference was found in hospital length of stay between the two groups (P>0.05). Symptoms of cough were significantly improved (82.2% vs. 70.0%, P=0.02) and wheezing was significantly reduced (0.7% vs. 12.9%, P<0.01) in the intervention group compared with the control group. During the trial, no disease progression or serious adverse events were reported. CONCLUSION Adding RYN to standard care may be a safe and effective treatment for children with asymptomatic and mild SARS-CoV-2 infection. (Registration No. ChiCTR2200060292).