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*

OBJECTIVES: To investigate the prognostic value of molecular minimal residual disease (Mol-MRD) monitored before and after allogeneic hematopoietic stem cell transplantation (HSCT) in pediatric acute myeloid leukemia (AML). METHODS: Clinical data of 71 pediatric AML patients who underwent HSCT between August 2016 and December 2023 were analyzed. Mol-MRD levels were dynamically monitored in MRD-positive patients, and survival outcomes were evaluated. RESULTS: No significant difference in the 3-year overall survival (OS) rate was observed between patients with pre-HSCT Mol-MRD ≥0.01% and <0.01% (77.3% ± 8.9% vs 80.4% ± 7.9%, P=0.705). However, patients with pre-HSCT Mol-MRD <1.75% had a significantly higher 3-year OS rate than those with Mol-MRD ≥1.75% (86.6% ± 5.6% vs 44.4% ± 16.6%, P=0.020). The median Mol-MRD level in long-term survivors was significantly lower than in non-survivors [0.61% (range: 0.04%-51.58%)] vs 10.60% (range: 1.90%-19.75%), P=0.035]. Concurrent flow cytometry-based MRD positivity was significantly higher in non-survivors (80% vs 24%, P=0.039). There was no significant difference in the 3-year overall survival rate between patients with Mol-MRD ≥0.01% and those with <0.01% at 30 days post-HSCT (P=0.527). For children with Mol-MRD <0.22% at 30 days post-HSCT, the 3-year overall survival rate was 80.4% ± 5.9%, showing no significant difference compared to those with molecular negativity (87.0% ± 7.0%) (P=0.523). CONCLUSIONS Patients with pre-HSCT Mol-MRD <1.75% or post-HSCT Mol-MRD <0.22% may achieve long-term survival outcomes comparable to Mol-MRD-negative cases through HSCT and targeted interventions.
Humans ; Hematopoietic Stem Cell Transplantation ; Neoplasm, Residual ; Leukemia, Myeloid, Acute/genetics* ; Child ; Male ; Female ; Child, Preschool ; Prognosis ; Adolescent ; Infant ; Transplantation, Homologous

BACKGROUND:Spinal cord injury often leads to neurogenic bladder with hyperreflexia of the forced urethral muscle,but there is a lack of clear understanding of its pathogenesis and treatment,and establishing a stable and reliable animal model has an important impact on revealing its pathomechanisms and exploring therapeutic approaches.OBJECTIVE:To investigate the effect of the number of times to urinate on neurogenic model rats after complete spinal cord transection in order to improve the postoperative survival and modeling rate of neurogenic model rats.METHODS:Out of 46 female Sprague-Dawley rats,6 were selected as the sham-operated group using the random number table method,and the remaining 40 rats were randomly divided into 0,1,3,and 5 times daily urination groups after complete spinal cord transection modeling,with 10 rats in each group.The residual urine volume was measured every 3 days within 19 postoperative days,and the survival and modeling were observed on the 19th day after the operation,and urodynamics tests and contraction experiments of isolated forced urethra muscle strips were performed.RESULTS AND CONCLUSION:(1)Survival and modeling rate:there was 10%survival rate and 10%modeling rate in the group of 0 times daily urination;20%survival rate and 10%modeling rate in the group of 1 time daily urination;70%survival rate and 70%modeling rate in the groups of 3 and 5 times daily urination.(2)Residual urine volume:compared with the sham-operated group,the residual urine volume of the groups of 3 and 5 times daily urination was significant increased on postoperative days 3,6,9,12,and 15(P<0.01);the residual urine volume of the groups of 3 and 5 times daily urination was increased on the 18th day after surgery(P<0.05).Compared with the 3 times daily urination group,the residual urine volume was decreased in the 5 times daily urination group on the 6th day after surgery(P<0.05),while there was no significant difference in the residual urine volume between the 3 and 5 times daily urination groups on the 3rd,9th,12th,15th,and 18th days after surgery.(3)Urodynamics:Compared with the sham-operated group,the differential pressure at the point of leakage was significantly reduced(P<0.01)and the maximal volume was significantly increased(P<0.01)in the 3 and 5 times daily urination groups.There was no statistical difference in the differential pressure at the point of leakage and the maximal volume between the 3 and 5 times daily urination groups.(4)Muscle-strip contraction test of isolated detrusor muscles:Compared with the sham-operated group,the contraction amplitude and frequency of detrusor muscle strips were significantly reduced in the 3 and 5 times daily urination groups(P<0.01).There was no statistically significant difference in the contraction amplitude and frequency of detrusor muscle strips between the 3 and 5 times daily-urination groups.In conclusion,assisted urination is one of the keys to establish a successful neurogenic model of urethral reflexes,and there is no significant difference in the effects of urinating 3 or 5 times a day on the neurogenic model.It is recommended to urinate at least 3 times a day based on the actual workload and the modeling rate.

Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Objective To observe the effects of electroacupuncture(EA)on TGF-β1/Smads signaling pathway and epithelial-mesenchymal transition(EMT)related proteins in rats with neurogenic bladder(NB)after spinal cord injury;To explore the possible mechanism of EA in improving NB fibrosis.Methods Totally 36 female SD rats were randomly selected,with 10 rats in the sham-operation group and the remaining 26 rats undergoing complete transection of the spinal cord beneath the T8 vertebrae to establish a NB rat model.The modeling rats were randomly divided into model group and EA group,with 10 rats in each group.EA group was applied to"Ciliao","Zhongji"and"Sanyinjiao",20 min per time,once a day for 7 days.The general condition of the rats in each group was observed,the ultrasound index of the bladder was detected by ultrasound technique,the bladder function of the rats was detected by urodynamics,the body mass of the rats and the wet weight of the bladder were recorded,and the bladder index was calculated.HE staining was used to observe bladder tissue morphology,the degree of bladder tissue fibrosis and bladder wall thickness were detected by Masson staining.The positive expressions of E-cadherin,N-cadherin and Vimentin in bladder tissue were detected by immunohistochemistry.The protein expressions of TGF-β1,p-Smad2/3,E-cadherin,N-cadherin and Vimentin were detected by Western blot.Results Compared with the sham-operation group,the upper and lower diameter,anteroposterior diameter,transverse diameter,bladder volume of the model group significantly increased(P<0.001),the maximum bladder pressure,leak point pressure difference,perfusion time and maximum bladder capacity significantly increased(P<0.001),the bladder index increased significantly(P<0.001),the bladder epithelial cells were thickened and arranged irregularly,the bladder collagen volume fraction and bladder wall thickness significantly increased(P<0.001),the expressions of TGF-β1,p-Smad2/3,N-cadherin and Vimentin in bladder tissue increased(P<0.01),and the expression of E-cadherin decreased(P<0.001).Compared with the model group,the upper and lower diameter,anteroposterior diameter,transverse diameter,bladder volume of the EA group decreased significantly(P<0.05),the maximum bladder pressure,leak point pressure difference,perfusion time and maximum bladder capacity significantly decreased(P<0.05),the bladder index significantly decreased(P<0.05),the thickness of the bladder epithelial cell layer became thinner and arranged more neatly,and the bladder collagen volume fraction and bladder wall thickness of the bladder were significantly reduced(P<0.05),the expressions of TGF-β1,p-Smad2/3,N-cadherin and Vimentin in bladder tissue significantly decreased(P<0.05),and the expression of E-cadherin significantly increased(P<0.05).Conclusion EA may reduce the EMT of bladder epithelial cells and decrease the degree of bladder tissue fibrosis by inhibiting the activation of the TGF-β1/Smads signaling pathway,thereby improving bladder function in NB rats after spinal cord injury.

BACKGROUND:Spinal cord injury often leads to neurogenic bladder with hyperreflexia of the forced urethral muscle,but there is a lack of clear understanding of its pathogenesis and treatment,and establishing a stable and reliable animal model has an important impact on revealing its pathomechanisms and exploring therapeutic approaches.OBJECTIVE:To investigate the effect of the number of times to urinate on neurogenic model rats after complete spinal cord transection in order to improve the postoperative survival and modeling rate of neurogenic model rats.METHODS:Out of 46 female Sprague-Dawley rats,6 were selected as the sham-operated group using the random number table method,and the remaining 40 rats were randomly divided into 0,1,3,and 5 times daily urination groups after complete spinal cord transection modeling,with 10 rats in each group.The residual urine volume was measured every 3 days within 19 postoperative days,and the survival and modeling were observed on the 19th day after the operation,and urodynamics tests and contraction experiments of isolated forced urethra muscle strips were performed.RESULTS AND CONCLUSION:(1)Survival and modeling rate:there was 10%survival rate and 10%modeling rate in the group of 0 times daily urination;20%survival rate and 10%modeling rate in the group of 1 time daily urination;70%survival rate and 70%modeling rate in the groups of 3 and 5 times daily urination.(2)Residual urine volume:compared with the sham-operated group,the residual urine volume of the groups of 3 and 5 times daily urination was significant increased on postoperative days 3,6,9,12,and 15(P<0.01);the residual urine volume of the groups of 3 and 5 times daily urination was increased on the 18th day after surgery(P<0.05).Compared with the 3 times daily urination group,the residual urine volume was decreased in the 5 times daily urination group on the 6th day after surgery(P<0.05),while there was no significant difference in the residual urine volume between the 3 and 5 times daily urination groups on the 3rd,9th,12th,15th,and 18th days after surgery.(3)Urodynamics:Compared with the sham-operated group,the differential pressure at the point of leakage was significantly reduced(P<0.01)and the maximal volume was significantly increased(P<0.01)in the 3 and 5 times daily urination groups.There was no statistical difference in the differential pressure at the point of leakage and the maximal volume between the 3 and 5 times daily urination groups.(4)Muscle-strip contraction test of isolated detrusor muscles:Compared with the sham-operated group,the contraction amplitude and frequency of detrusor muscle strips were significantly reduced in the 3 and 5 times daily urination groups(P<0.01).There was no statistically significant difference in the contraction amplitude and frequency of detrusor muscle strips between the 3 and 5 times daily-urination groups.In conclusion,assisted urination is one of the keys to establish a successful neurogenic model of urethral reflexes,and there is no significant difference in the effects of urinating 3 or 5 times a day on the neurogenic model.It is recommended to urinate at least 3 times a day based on the actual workload and the modeling rate.

Objective To observe the effects of electroacupuncture(EA)on TGF-β1/Smads signaling pathway and epithelial-mesenchymal transition(EMT)related proteins in rats with neurogenic bladder(NB)after spinal cord injury;To explore the possible mechanism of EA in improving NB fibrosis.Methods Totally 36 female SD rats were randomly selected,with 10 rats in the sham-operation group and the remaining 26 rats undergoing complete transection of the spinal cord beneath the T8 vertebrae to establish a NB rat model.The modeling rats were randomly divided into model group and EA group,with 10 rats in each group.EA group was applied to"Ciliao","Zhongji"and"Sanyinjiao",20 min per time,once a day for 7 days.The general condition of the rats in each group was observed,the ultrasound index of the bladder was detected by ultrasound technique,the bladder function of the rats was detected by urodynamics,the body mass of the rats and the wet weight of the bladder were recorded,and the bladder index was calculated.HE staining was used to observe bladder tissue morphology,the degree of bladder tissue fibrosis and bladder wall thickness were detected by Masson staining.The positive expressions of E-cadherin,N-cadherin and Vimentin in bladder tissue were detected by immunohistochemistry.The protein expressions of TGF-β1,p-Smad2/3,E-cadherin,N-cadherin and Vimentin were detected by Western blot.Results Compared with the sham-operation group,the upper and lower diameter,anteroposterior diameter,transverse diameter,bladder volume of the model group significantly increased(P<0.001),the maximum bladder pressure,leak point pressure difference,perfusion time and maximum bladder capacity significantly increased(P<0.001),the bladder index increased significantly(P<0.001),the bladder epithelial cells were thickened and arranged irregularly,the bladder collagen volume fraction and bladder wall thickness significantly increased(P<0.001),the expressions of TGF-β1,p-Smad2/3,N-cadherin and Vimentin in bladder tissue increased(P<0.01),and the expression of E-cadherin decreased(P<0.001).Compared with the model group,the upper and lower diameter,anteroposterior diameter,transverse diameter,bladder volume of the EA group decreased significantly(P<0.05),the maximum bladder pressure,leak point pressure difference,perfusion time and maximum bladder capacity significantly decreased(P<0.05),the bladder index significantly decreased(P<0.05),the thickness of the bladder epithelial cell layer became thinner and arranged more neatly,and the bladder collagen volume fraction and bladder wall thickness of the bladder were significantly reduced(P<0.05),the expressions of TGF-β1,p-Smad2/3,N-cadherin and Vimentin in bladder tissue significantly decreased(P<0.05),and the expression of E-cadherin significantly increased(P<0.05).Conclusion EA may reduce the EMT of bladder epithelial cells and decrease the degree of bladder tissue fibrosis by inhibiting the activation of the TGF-β1/Smads signaling pathway,thereby improving bladder function in NB rats after spinal cord injury.

Objective:To explore the safety and efficacy of intraosseous regional administration (IORA) of vancomycin for preventing infection in primary total knee arthroplasty (TKA).Methods:A total of 124 patients with knee osteoarthritis undergoing TKA between February 2024 and May 2024 at nine hospitals were enrolled. Preoperative infection prophylaxis involved either IORA (0.5 g vancomycin administered via intraosseous regional infusion before incision) or intravenous infusion (1 g vancomycin via peripheral vein). The IORA group included 15 males and 47 females with a median age of 66.5 years (range, 60.0-70.0 years), while the intravenous group included 14 males and 48 females with a median age of 66.0 years (range, 61.8-70.3 years) years. Intraoperative samples were collected including fat and synovium tissues after incision, before prosthesis placement, and after tourniquet release; distal femoral cancellous bone during femoral osteotomy; proximal tibial cancellous bone during tibial osteotomy; proximal intercondylar cancellous bone before prosthesis placement; and peripheral blood from non-infused arms at surgery initiation and after tourniquet release. Vancomycin concentrations were measured using liquid chromatography-tandem mass spectrometry. Vital sign changes were recorded from admission to 5~10 minutes post-IORA (IORA group) or post-incision (intravenous group). Follow-ups were conducted on postoperative day 1 and 3, and at 1 and 3 months, to document complications including IORA-related adverse events, periprosthetic joint infections, surgical site infections, red man syndrome, acute kidney injury, deep vein thrombosis and so on.Results:Vancomycin concentrations in bone, fat, and synovial tissue samples were significantly higher in the IORA group than in the intravenous group ( P<0.05), while vancomycin concentrations in blood samples were significantly lower in the IORA group than in the intravenous group ( P<0.05). Only 7.3%(41/558) of tissue samples in the IORA group had vancomycin concentrations below 2.0 μg/g (the minimum inhibitory concentration of vancomycin against coagulase-negative staphylococcus), compared to 59.3%(331/558) in the intravenous group (χ 2=11.285, P<0.001). In the intravenous group, 16.9%(21/124) of blood samples had vancomycin concentrations exceeding 15.0 mg/L (the threshold associated with a significantly increased risk of nephrotoxicity), while all concentrations in the IORA group were below this threshold, the difference was statistically significant (χ 2=22.943, P<0.001). There were no statistically significant difference ( P>0.05) in vital signs changes before and after vancomycin administration between the two groups. Two patients in the intravenous group experienced incision exudate, while no other related complications occurred in either group. Conclusions:Compared to the traditional intravenous infusion of 1 g vancomycin, intraosseous injection of a low dose (0.5 g) of vancomycin achieves higher local tissue concentrations in the knee joint with a lower incidence of adverse reactions and is safe for infection prophylaxis. Despite guidelines not recommending the routine use of vancomycin for preventing infection after primary TKA, intraosseous injection of 0.5 g vancomycin may be considered intraoperatively for primary TKA in the following scenarios: patients in medical institutions with a high prevalence of methicillin-resistant staphylococcus aureus (MRSA) infections, patients with potential preoperative MRSA colonization, or patients with cephalosporin allergy.

Objective To develop a time-resolved fluorescent immunoassay kit for the rapid,accurate and quantitative detection of S100B protein in serum and to evaluate its performance.Methods The test strip was prepared using time-resolved fluorescent microsphere-labeled anti-S100B polyclonal antibody and rabbit IgG antibody,labeling pads,sample pads,S100B nitrocellulose films and absorbent paper,and an S100B time-resolved fluorescence immunoassay kit was obtained by assembling the cartridge.The performance of the kit developed was evaluated by standard curve,accuracy,minimum detection limit,linear interval,specificity,reproducibility and stability.The reference intervals of 199 pieces of healthy human serum and plasma samples from a certain region were detected with the kit,and the clinical performance of the kit and Roche Elecsys S100 kit was tested by synchronous blind method to assess the consistency of the results of the two kits for 142 samples.Results The S100B time-resolved fluorescence immunoassay kit had the standard curve beingy=(1.133 02+1.752 24)/[1+(x/1.082 20)×(-0.603 52)]-1.752 24,R2=0.999 08 and the linear range being[0.05,30]ng/mL,which met the requirements of the relative deviation of the accuracy within±15％,the minimum detection limit not hgier than 0.05 ng/mL,the relative deviation of specificity within±15％and the coefficient of variation of intra-and inter-batch difference less than 15％.The stability test results indicated that the kit was valid for 12 months at 2-30 ℃ conditions.The reference intervals of serum and plasma samples measured by the kit were both lower than 0.3 ng/mL.Clinical trials showed that the results by the kit and Roche Elecsys S100 Assay Kit were in high agreement(Kappa=0.906 1＞0.80)and met the requirements.Conclusion The kit developed detects the concentration of S100B protein in serum quickly,accurately and quantitatively,and provides references for the diagnosis and treatment of neurological diseases,autoimmune diseases,cerebrovascular diseases and etc.[Chinese Medical Equipment Journal,2024,45(1):47-55]

Objective:To investigate the effect and mechanism of Grifola frondosa extract on inflammatory response of colon tissue in rats with ulcerative colitis(UC)by regulating interleukin-6(IL-6)/Janus kinase 2(JAK2)/signal transducer and activator of transcription 3(STAT3)signaling pathway.Methods:Forty SD rats were randomly divided into blank control group,UC model group,Grifola frondosa treatment group,western medicine treatment group and combined treatment group,with 8 rats in each group.After UC rats were established by free drinking 3%DSS for 7 days,the treatment group were given Grifola frondosa extract 10 mg/(kg·d),sulfasalazine 0.3 g/(kg·d),and the same amount of two drugs,for 14 consecutive days.During the experiment,general state of rats were observed,and the disease activity index(DAI)score was calculated;pathological changes of rats colon tissue were observed by HE staining;protein expression levels of IL-6,JAK2,STAT3 and p-STAT3 in rats colon tissue were detected by Western blot;content of IL-6 in rats serum was detected by ELISA;protein contents and expressions of IL-6R and MPO in rats colon tissue were determined by immunohistochemistry.Results:Compared with blank control group,general state of rats in UC model group was poor,DAI score was increased,obvious tissue mucosal defects and inflammatory cell infiltration were observed by HE staining;protein expression levels of IL-6,JAK2,STAT3 and p-STAT3 in rats colon tissue and contents of IL-6R and MPO were significantly increased(P<0.01);content of IL-6 in rats serum was significantly increased(P<0.01),the difference was statistically significant.Compared with UC model group,general condition of rats in each treatment group was improved,DAI score was decreased,HE staining showed that mucosal defects were improved to varying degrees,and occasionally inflammatory cell infiltration was observed;protein expression levels of IL-6,JAK2,STAT3 and p-STAT3 in colon tissue were significantly decreased(P<0.01),contents of IL-6R and MPO in colon tissue and content of IL-6 in serum were significantly decreased(P<0.01 or P<0.05),the differences were statistically significant.Conclusion:Grifola frondosa extract can reduce the inflammatory response in colon tissue of UC rats by regulating expressions of IL-6/JAK2/STAT3 signaling pathway related factors.