OBJECTIVE: To evaluate the filling quality of single cone obturation in root canal model with irregular structure (Hus&Kim Ⅴ, Yin Ⅱ-type isthmus) which established by 3D printing technology using slices and radiographic methods, in order to provide reference for clinical practice. METHODS: (1) Extracted fresh premolars with Hus&Kim Ⅴ and Yin-type Ⅱ isthmus were collected and scanned by cone-beam computed tomography (CBCT), then standard root canal models were designed and printed. Rhodamine B staining and bias fitting were used to verify the availability of the models. (2) 30 root canal models were randomly divided into 3 groups according to different filling methods (n=10). CONTROL GROUP: vertical compaction obturation; Experimental group 1: single cone obturation with 0.06-taper cone (30#); Experimental group 2: single cone obturation with 0.04-taper cone (35#), GuttaFlow 2 as canal sealers. Slices were taken at 2, 4, 6, and 8 mm from the root apex in the direction perpendicular to the long axis of the root and observed under a stereomicroscope to calculate the percentage of filling area (PAV), percentage of gutta-percha-filled area (PGFA), percentage of sealer filled area (PSFA). (3) On the basis of the above results, two groups (n=4) were selected to further analyze the filling quality by micro-computed tomography (Micro-CT), the filling volume of main root canal and the isthmus were obtained, and the percentage of filling volume (PFV) was calculated. Two-way ANOVA was used to evaluate the differences between the groups, and Tukey' s multiple comparison was used to compare the data between the groups and within the groups. RESULTS: (1) Rhodamine B staining solution could overflow the apical foramen, and the main root canal system and the isthmus area were stained, showed no remnants of support material. The 3D standard deviation of the printed model data was 0.03 mm, and the average fitting distance was 0.02 mm. (2) The PFA of the two experimental groups were both significantly lower than that of the control group (F=45.04, P < 0.01). There was no statistical difference of the PFA at apical 2 and 4 mm between the two experimental groups (P>0.01), but at the middle and coronal portions of the root canal (6, 8 mm), the PFA of the experimental group 1 was higher than that of the experimental group 2 (P < 0.01). PFA in the apical 2, 4 mm of the two experimental groups were both lower than that in the middle and coronal portions 6, 8 mm of the canal (P < 0.01). There was no difference in the PGFA and PSFA between the two experimental groups at the apical 2, 4 mm (F=2.383, P>0.01). (3) The results of Micro-CT showed that the PFV of the experimental group 1 was statistically different with the control group (F=47.33, P < 0.01). The PFV of the experimental group 1 was 54.33%±4.35% in the isthmus and 78.31%±4.21% in the main root canal, which were both lower than the PFV of the control group of 76.48%±4.89% (isthmus) and 86.90%±3.29% (main root canal, P < 0.01). The PFV of the main root canal in the experimental group 1 was higher than that in the isthmus (P < 0.01), while there was no difference between the isthmus and the main root canal in the control group (P>0.01). CONCLUSION In the irregular root canal structure with isthmus, using large-taper gutta-percha can improve the filling quality of the middle and upper part of the canal, but the percentage of filling volume in the isthmus is lower than that of the main canal, and more technical improvements are needed.
Humans ; Root Canal Obturation/methods* ; Cone-Beam Computed Tomography ; Root Canal Filling Materials ; Dental Pulp Cavity/diagnostic imaging* ; Printing, Three-Dimensional ; In Vitro Techniques ; Gutta-Percha ; Bicuspid

Mannheimia varigena(M.varigena)is a significant pathogen causing bovine respiratory disease.Transferrin binding protein B(TbpB)is a lipoprotein directly exposed to the outer mem-brane of the cell,which is not only involved in the bacterial iron metabolism pathway,but also an important virulence factor.This study aims to lay the groundwork for developing novel subunit vaccines by conducting site-directed mutagenesis on M.varigena TbpB binding-related residues and evaluating their immunogenicity.Based on whole-genome sequencing of a bovine M.varigena i-solate,its iron uptake pathway was predicted.Key amino acid residues of M.varigena TbpB that play a role for binding to bovine transferrin(bTf)was identified by bioinformatics.We constructed two M.varigena TbpB mutants(Y205A and Y258A)and assessed their bTf binding activity and immunogenicity through dot blot assays and mouse immunization studies.Dot blot assays result showed that the Y258A mutation caused TbpB to lose its ability to bind to bTf.Mouse immuniza-tion studies showed that,compared to wild-type TbpB,the mutants of TbpB induced higher levels of specific antibodies.In challenge experiments,mice immunized with mutant TbpB exhibited high-er survival rates.These results demonstrate that site-directed mutagenesis can enhance the immu-nogenicity of TbpB.This study provides a novel approach for developing new subunit vaccines a-gainst M.varigena.

Acute symptomatic osteoporotic thoracolumbar compression fracture (ASOTLF) can lead to chronic low back pain, kyphosis deformity, pulmonary dysfunction, loss of mobility, and even life-threatening complications. Vertebral augmentation is currently the mainstream treatment method for this condition. In 2019, the Editorial Board of Chinese Journal of Trauma and the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association collaboratively led the development of Clinical guideline for vertebral augmentation for acute symptomatic osteoporotic thoracolumbar compression fractures. Six years later, with advances in clinical diagnosis and treatment techniques as well as accumulating evidence in related fields, the 2019 guideline requires updating. To this end, the Spinal Trauma Group of Orthopedic Surgeons Branch of Chinese Medical Doctor Association, the Spinal Health Professional Committee of China Human Health Science and Technology Promotion Association, and the Minimally Invasive Orthopedics Professional Committee of Shaanxi Medical Doctor Association have organized experts in the field to develop the Clinical guideline for vertebral augmentation of acute symptomatic osteoporotic thoracolumbar compression fractures ( version 2025) , based on the latest evidence-based medical researches. This guideline incorporates 3 recommendations retained from the 2019 version with updated strength of evidence, along with 12 new recommendations. It provides recommendations from six aspects of diagnosis, pain management, treatment option selection, prevention of postoperative complications, anti-osteoporosis therapy, and postoperative rehabilitation, aiming to provide a reference for standard treatment of vertebral augmentation for ASOTLF in hospitals at all levels.

Objective:To evaluate the efficacy of eculizumab in treating hematopoietic stem cell transplantation-associated thrombotic microangiopathy (TA-TMA) .Methods:This retrospective study included 11 patients who developed TA-TMA after allogeneic hematopoietic stem cell transplantation and subsequently received eculizumab treatment at Peking University People′s Hospital between June 2018 and May 2024. The incidence of TA-TMA, treatment details, and clinical outcomes were analyzed.Results:Among the 11 included patients [4 males, 7 females; median age: 29 years (range: 9-56) ], underlying diseases were severe aplastic anemia (SAA) in 5 patients, acute lymphoblastic leukemia (ALL) in 3 patients, and acute myeloid leukemia (AML) in 3 patients. The median time to TA-TMA diagnosis was 48 days post-transplantation (range: 4-213 days), and all patients met the diagnostic criteria for high-risk TA-TMA. The median interval from TA-TMA diagnosis to the initiation of eculizumab treatment was 12 days (range: 1-56 days). Patients received a median of 3 doses of eculizumab (range: 1-14). Ten of the 11 patients were assessed as having no response (NR) to eculizumab at the end of treatment or at death. One patient achieved a partial response (PR) but subsequently died after TA-TMA relapsed due to infection. At the last follow-up, all patients were either lost to follow-up or had died. The median follow-up duration was 88 days (range: 33-326 days), and the median time from TA-TMA diagnosis to the last follow-up was 31 days (range: 21-113 days) .Conclusion:Eculizumab demonstrated poor efficacy in this TA-TMA cohort. This might be attributable to the critical and complex condition of the patients, delayed initiation of eculizumab treatment, and insufficient dosage.

Objective:To observe any effect of dynamic instability training on the balance and posture control of persons with chronic ankle instability (CAI).Methods:Thirty persons with CAI were divided at random into a control group and an observation group, each of 15. Both groups received routine rehabilitation interventions (including ankle strength training, kinesio taping, and vibration training), while the observation group additionally underwent 20 minutes of dynamic instability training daily, 5 days a week for 4 consecutive weeks. Before and after the treatment, everyone′s balance was evaluated using the Berg balance scale (BBS) and the star moving balance test (SEBT). Surface electromyography (sEMG) was used to collect electromyograms of the affected peroneus longus, tibialis anterior, rectus femoris and medialis femoris muscles of both groups within 100ms before and after landing in the jump-landing test. The intensity of muscle activation was thus analyzed.Results:After the treatment there was significant improvement in the average BBS scores, anterior medial SEBT, medial SEBT and posterior medial SEBT results of both groups. On average, all three SEBT results [(80.27±4.06)cm, (90.27±4.06)cm and (97.73±3.47)cm respectively] were significantly better in the observation group than in the control group. The standardized integrated electromyographs of the peroneus longus, tibialis anterior, rectus femoris and medialis femoris muscles on the affected sides showed significant improvement compared with before the treatment, but there too the observation group′s results were significantly better than those of the control group.Conclusions:Combining dynamic instability training with conventional rehabilitation can further improve the balance and postural control of persons with chronic ankle instability.

Objective To explore the value of diffusion kurtosis imaging(DKI)in the diagnosis of Parkinson's disease with mild cognitive impairment(PD-MCI)patients.Methods A total of 18 patients with Parkinson's disease cognitive normal(PDN),22 patients with PD-MCI,and 24 healthy controls(HC)were prospectively included.All participants underwent DKI,and regions of interest(ROI)were selected in the substantia nigra,red nucleus,striatum,and posterior cingulate gyrus for post-processing.The diagnostic efficacy of DKI parameters on PD patients' cognitive status was analyzed by the receiver operating characteristic(ROC)curve.Results Compared with the PDN group,the PD-MCI group had a longer disease duration and a higher H-Y stage.Compared with the HC group,the PD-MCI group showed significantly lower mean kurtosis(MK),radial kurtosis(RK),axial kurtosis(AK),and fractional anisotropy(FA)values in the substantia nigra and posterior cingulate gyrus.In the PDN group,FA and MK values in the substantia nigra were significantly decreased,while FA values in the striatum and posterior cingulate gyrus were significantly increased(P＜0.05).Compared with the PDN group,the PD-MCI group showed significantly decreased DKI parameter values in the substantia nigra and posterior cingulate gyrus,and significantly decreased RK,AK,and FA values in the striatum(P＜0.05).The FA values of striatum,posterior cingulate gyrus and joint predictors were the most effective in the diagnosis of PD-MCI and the area under the curve(AUC)were 0.826,0.853 and 0.960,respectively.Conclusion DKI can detect microstructural changes in PD patients.Microstructural alterations in the striatum and posterior cingulate gyrus have an impact on early cognitive function changes in PD patients.FA demonstrate high sensitivity and specificity in the diagnosis of PD-MCI,and the combined diagnostic efficacy across multiple regions is even higher.

Objective:To evaluate the filling quality of single cone obturation in root canal model with irregular structure(Hus&Kim Ⅴ,Yin Ⅱ-type isthmus)which established by 3D printing technology using slices and radiographic methods,in order to provide reference for clinical practice.Methods:(1)Extracted fresh premolars with Hus&Kim Ⅴ and Yin-type Ⅱ isthmus were collected and scanned by cone-beam computed tomography(CBCT),then standard root canal models were designed and printed.Rhodamine B staining and bias fitting were used to verify the availability of the models.(2)30 root canal models were randomly divided into 3 groups according to different filling methods(n=10).Control group:vertical compaction obturation;Experimental group 1:single cone obturation with 0.06-taper cone(30#);Experimental group 2:single cone obturation with 0.04-taper cone(35#),GuttaFlow 2 as canal sealers.Slices were taken at 2,4,6,and 8 mm from the root apex in the direction perpendicular to the long axis of the root and observed under a stereomicroscope to calculate the percentage of filling area(PAV),percentage of gutta-percha-filled area(PGFA),percentage of sealer filled area(PSFA).(3)On the basis of the above results,two groups(n=4)were selected to further analyze the filling quality by micro-computed tomography(Micro-CT),the filling volume of main root canal and the isthmus were obtained,and the percentage of filling volume(PFV)was calculated.Two-way ANOVA was used to evaluate the differences between the groups,and Tukey's multiple comparison was used to compare the data between the groups and within the groups.Results:(1)Rhodamine B staining solution could over-flow the apical foramen,and the main root canal system and the isthmus area were stained,showed no remnants of support material.The 3D standard deviation of the printed model data was 0.03 mm,and the average fitting distance was 0.02 mm.(2)The PFA of the two experimental groups were both significant-ly lower than that of the control group(F=45.04,P＜0.01).There was no statistical difference of the PFA at apical 2 and 4 mm between the two experimental groups(P＞0.01),but at the middle and coro-nal portions of the root canal(6,8 mm),the PFA of the experimental group 1 was higher than that of the experimental group 2(P＜0.01).PFA in the apical 2,4 mm of the two experimental groups were both lower than that in the middle and coronal portions 6,8 mm of the canal(P＜0.01).There was no difference in the PGFA and PSFA between the two experimental groups at the apical 2,4 mm(F=2.383,P＞0.01).(3)The results of Micro-CT showed that the PFV of the experimental group 1 was statistically different with the control group(F=47.33,P＜0.01).The PFV of the experimental group 1 was 54.33％±4.35％in the isthmus and 78.31％±4.21％in the main root canal,which were both lower than the PFV of the control group of 76.48％±4.89％(isthmus)and 86.90％±3.29％(main root canal,P＜0.01).The PFV of the main root canal in the experimental group 1 was higher than that in the isthmus(P＜0.01),while there was no difference between the isthmus and the main root canal in the control group(P＞0.01).Conclusion:In the irregular root canal structure with isthmus,using large-taper gutta-percha can improve the filling quality of the middle and upper part of the canal,but the percentage of filling volume in the isthmus is lower than that of the main canal,and more technical im-provements are needed.

Objective:To evaluate the filling quality of single cone obturation in root canal model with irregular structure(Hus&Kim Ⅴ,Yin Ⅱ-type isthmus)which established by 3D printing technology using slices and radiographic methods,in order to provide reference for clinical practice.Methods:(1)Extracted fresh premolars with Hus&Kim Ⅴ and Yin-type Ⅱ isthmus were collected and scanned by cone-beam computed tomography(CBCT),then standard root canal models were designed and printed.Rhodamine B staining and bias fitting were used to verify the availability of the models.(2)30 root canal models were randomly divided into 3 groups according to different filling methods(n=10).Control group:vertical compaction obturation;Experimental group 1:single cone obturation with 0.06-taper cone(30#);Experimental group 2:single cone obturation with 0.04-taper cone(35#),GuttaFlow 2 as canal sealers.Slices were taken at 2,4,6,and 8 mm from the root apex in the direction perpendicular to the long axis of the root and observed under a stereomicroscope to calculate the percentage of filling area(PAV),percentage of gutta-percha-filled area(PGFA),percentage of sealer filled area(PSFA).(3)On the basis of the above results,two groups(n=4)were selected to further analyze the filling quality by micro-computed tomography(Micro-CT),the filling volume of main root canal and the isthmus were obtained,and the percentage of filling volume(PFV)was calculated.Two-way ANOVA was used to evaluate the differences between the groups,and Tukey's multiple comparison was used to compare the data between the groups and within the groups.Results:(1)Rhodamine B staining solution could over-flow the apical foramen,and the main root canal system and the isthmus area were stained,showed no remnants of support material.The 3D standard deviation of the printed model data was 0.03 mm,and the average fitting distance was 0.02 mm.(2)The PFA of the two experimental groups were both significant-ly lower than that of the control group(F=45.04,P＜0.01).There was no statistical difference of the PFA at apical 2 and 4 mm between the two experimental groups(P＞0.01),but at the middle and coro-nal portions of the root canal(6,8 mm),the PFA of the experimental group 1 was higher than that of the experimental group 2(P＜0.01).PFA in the apical 2,4 mm of the two experimental groups were both lower than that in the middle and coronal portions 6,8 mm of the canal(P＜0.01).There was no difference in the PGFA and PSFA between the two experimental groups at the apical 2,4 mm(F=2.383,P＞0.01).(3)The results of Micro-CT showed that the PFV of the experimental group 1 was statistically different with the control group(F=47.33,P＜0.01).The PFV of the experimental group 1 was 54.33％±4.35％in the isthmus and 78.31％±4.21％in the main root canal,which were both lower than the PFV of the control group of 76.48％±4.89％(isthmus)and 86.90％±3.29％(main root canal,P＜0.01).The PFV of the main root canal in the experimental group 1 was higher than that in the isthmus(P＜0.01),while there was no difference between the isthmus and the main root canal in the control group(P＞0.01).Conclusion:In the irregular root canal structure with isthmus,using large-taper gutta-percha can improve the filling quality of the middle and upper part of the canal,but the percentage of filling volume in the isthmus is lower than that of the main canal,and more technical im-provements are needed.

Mannheimia varigena(M.varigena)is a significant pathogen causing bovine respiratory disease.Transferrin binding protein B(TbpB)is a lipoprotein directly exposed to the outer mem-brane of the cell,which is not only involved in the bacterial iron metabolism pathway,but also an important virulence factor.This study aims to lay the groundwork for developing novel subunit vaccines by conducting site-directed mutagenesis on M.varigena TbpB binding-related residues and evaluating their immunogenicity.Based on whole-genome sequencing of a bovine M.varigena i-solate,its iron uptake pathway was predicted.Key amino acid residues of M.varigena TbpB that play a role for binding to bovine transferrin(bTf)was identified by bioinformatics.We constructed two M.varigena TbpB mutants(Y205A and Y258A)and assessed their bTf binding activity and immunogenicity through dot blot assays and mouse immunization studies.Dot blot assays result showed that the Y258A mutation caused TbpB to lose its ability to bind to bTf.Mouse immuniza-tion studies showed that,compared to wild-type TbpB,the mutants of TbpB induced higher levels of specific antibodies.In challenge experiments,mice immunized with mutant TbpB exhibited high-er survival rates.These results demonstrate that site-directed mutagenesis can enhance the immu-nogenicity of TbpB.This study provides a novel approach for developing new subunit vaccines a-gainst M.varigena.

Objective To explore the value of diffusion kurtosis imaging(DKI)in the diagnosis of Parkinson's disease with mild cognitive impairment(PD-MCI)patients.Methods A total of 18 patients with Parkinson's disease cognitive normal(PDN),22 patients with PD-MCI,and 24 healthy controls(HC)were prospectively included.All participants underwent DKI,and regions of interest(ROI)were selected in the substantia nigra,red nucleus,striatum,and posterior cingulate gyrus for post-processing.The diagnostic efficacy of DKI parameters on PD patients' cognitive status was analyzed by the receiver operating characteristic(ROC)curve.Results Compared with the PDN group,the PD-MCI group had a longer disease duration and a higher H-Y stage.Compared with the HC group,the PD-MCI group showed significantly lower mean kurtosis(MK),radial kurtosis(RK),axial kurtosis(AK),and fractional anisotropy(FA)values in the substantia nigra and posterior cingulate gyrus.In the PDN group,FA and MK values in the substantia nigra were significantly decreased,while FA values in the striatum and posterior cingulate gyrus were significantly increased(P＜0.05).Compared with the PDN group,the PD-MCI group showed significantly decreased DKI parameter values in the substantia nigra and posterior cingulate gyrus,and significantly decreased RK,AK,and FA values in the striatum(P＜0.05).The FA values of striatum,posterior cingulate gyrus and joint predictors were the most effective in the diagnosis of PD-MCI and the area under the curve(AUC)were 0.826,0.853 and 0.960,respectively.Conclusion DKI can detect microstructural changes in PD patients.Microstructural alterations in the striatum and posterior cingulate gyrus have an impact on early cognitive function changes in PD patients.FA demonstrate high sensitivity and specificity in the diagnosis of PD-MCI,and the combined diagnostic efficacy across multiple regions is even higher.