Objective:To evaluate the effect of polyetheretherketone (PEEK) periodontal splints and splints made from other materials under static loading on stress distributions in periodontal tissues, cement layer, and splints themselves.Methods:A finite element model based on cone-beam CT imaging data of a 25-year-old male patient (treated at the Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University in October 2021 for a cracked maxillary molar) with a healthy and intact mandibular dentition and periodontal health was constructed. The finite element model included anterior mandible dentition, mandibular bone model without bone resorption (WBR group), a periodontally compromised mandible model (control group), and three types of periodontal splints: a PEEK periodontal splint (0.7 mm thick, Young′s modulus: 4.1 MPa), a fiber-reinforced resin (FRC) splint (1.0 mm thick, Young′s modulus: 37.0 MPa), and a titanium splint (1.2 mm thick, Young′s modulus: 110.0 MPa). The bone resorption models fixed with different periodontal splints constituted the experimental groups (PEEK group, FRC group and titanium group). Loading of 100 N was applied on the midpoint of the incisal edge of tooth 41. The direction was set at 0°, which was parallel to the long axis of the tooth and downward. The buccal to lingual and downward angles were 30°and 60°, respectively, perpendicular to the long axis of the tooth and 90° to the lingual side. The finite element analysis software was utilized to analyze the stress distribution characteristics of the periodontal tissues, adhesive layer, and the splint itself in the anterior mandibular teeth among the different group.Results:Under the different loading simulation, in the control group, the maximal von Mises stresses of periodontal ligament and bone were 15.7-50.2 MPa and 38.8-130.3 MPa, respectively, and in the WBR group, the maximal von Mises stresses of periodontal ligament and bone were 3.6-6.4 MPa and 16.5-42.7 MPa, respectively. Under the same loading conditions, the magnitude of maximal von Mises stresses in periodontal tissues in the PEEK group was 4.6-6.2 MPa, and the magnitude of stresses in the periodontal ligament of 41 teeth in the WBR group was similar to that in the PEEK group, but higher than that in the FRC and titanium groups. The maximal von Mises stresses of each group is primarily distributed in the periodontal ligament and alveolar bone at the cervical area of the tooth. The higher the elastic modulus of the splint, the higher its own maximal von Mises stresses, and the smaller the maximal principal stresses transmitted to the adhesive layer. In the PEEK group and titanium group, the stress distribution area in the adhesive layer and the splint was near the splint connection adjacent to tooth 41.Conclusions:Periodontal splints fabricated from three types of materials, are effective in distributing stress within the periodontal tissues of the abutment teeth. Compared to FRC and titanium group, the higher PEEK splint stress value was obtained, and the smaller the stress value was transmitted to its adhesive layer.

Objective To investigate the role of macrophages in the process of fine particulate matter (PM2.5)exposure induced damage to pulmonary blood-air barrier.Methods Eighteen male BALB/C mice (aged of 10 weeks,weighing 24～27 g)were randomly divided into control group and low-and high-dose PM2.5 exposure groups (receiving 1 .8 and 16.2 mg/kg,respectively),with 6 mice in each group.The control group received tracheal instillations of normal saline on days 1,4,and 7,whereas the exposure groups were administered corresponding dose of PM2.5 exposure at the same time points.In 24 h after last exposure,pathological changes in the lung tissues were observed,and the contents of total protein (TP ),lactate dehydrogenase (LDH ),and alkaline phosphatase (AKP ) in bronchoalveolar lavage fluid (BALF ),and F4/80 protein level in lung tissue were measured to evaluate the blood-air barrier damage and macrophage infiltration within the lung tissues.Additionally,an in vitro model of the blood-air barrier was established using A549 alveolar epithelial cells and EA.hy926 vascular endothelial cells.In combination with a THP-1 macrophage model,the supernatant PM2.5 supernatant,macrophage supernatant,and PM2.5-macrophage supernatant were incubated with the barrier model for 24 h,respectively.Transmembrane electrical resistance (TEER),sodium fluorescein permeability of the barrier model,and LDH release from the barrier cells were measured to ascertain the extent of macrophage-mediated enhancement in barrier damage induced by PM2.5 exposure.Furthermore,the expression of inflammatory cytokines,such as TNF-α,IL-1β,IL-6,and IL-8 in the macrophages after PM2.5 exposure was analyzed with quantitative real-time PCR (qPCR)and enzyme-linked immunosorbent assay (ELISA).Results PM2.5 exposure induced lung tissue damage in mice in a dose-dependent manner,significantly elevated the contents of TP,LDH and AKP in the BALF and caused marked infiltration of macrophages into the lung tissue,especially the high-dose exposure when compared with the mice from the control group (P<0.01 ).In vitro barrier model exposure experiments showed that in comparison with the treatment of 150 and 300 μg/mL PM2.5 and macrophage supernatant,the same doses of PM2.5-macrophage supernatant resulted in notably decreased TEER and significantly enhanced permeability in the barrier model (P<0.01 ),and markedly increased LDH release from epithelial and endothelial barrier cells (P<0.01 ).Additionally,the exposure of 150 and 300μg/mL PM2.5 led to a significant up-regulation of TNF-α,IL-1β,IL-6,and IL-8 in the macrophages (P<0.01 ).Conclusion Macrophages deteriorate PM2.5-induced functional impairment of the pulmonary blood-air barrier.

Background/Aims: Four-week treatment of linvencorvir (RO7049389) was generally safe and well tolerated, and showed anti-viral activity in chronic hepatitis B (CHB) patients. This study evaluated the efficacy, safety, and pharmacokinetics of 48-week treatment with linvencorvir plus standard of care (SoC) in CHB patients. Methods: This was a multicentre, non-randomized, non-controlled, open-label phase 2 study enrolling three cohorts: nucleos(t)ide analogue (NUC)-suppressed patients received linvencorvir plus NUC (Cohort A, n=32); treatment-naïve patients received linvencorvir plus NUC without (Cohort B, n=10) or with (Cohort C, n=30) pegylated interferon-α (Peg-IFN-α). Treatment duration was 48 weeks, followed by NUC alone for 24 weeks. Results: 68 patients completed the study. No patient achieved functional cure (sustained HBsAg loss and unquantifiable HBV DNA). By Week 48, 89% of treatment-naïve patients (10/10 Cohort B; 24/28 Cohort C) reached unquantifiable HBV DNA. Unquantifiable HBV RNA was achieved in 92% of patients with quantifiable baseline HBV RNA (14/15 Cohort A, 8/8 Cohort B, 22/25 Cohort C) at Week 48 along with partially sustained HBV RNA responses in treatment-naïve patients during follow-up period. Pronounced reductions in HBeAg and HBcrAg were observed in treatment-naïve patients, while HBsAg decline was only observed in Cohort C. Most adverse events were grade 1–2, and no linvencorvir-related serious adverse events were reported. Conclusions 48-week linvencorvir plus SoC was generally safe and well tolerated, and resulted in potent HBV DNA and RNA suppression. However, 48-week linvencorvir plus NUC with or without Peg-IFN did not result in the achievement of functional cure in any patient.

Objective:To compare the efficacy of 2 fixation modes [dynamic hip screw (DHS) plus anti-rotation screw versus 3 cannulated compression screws (CCS)] in the treatment of femoral neck fractures complicated with comminuted posterior wall.Methods:The data were analyzed retrospectively of the 109 patients who had been treated for femoral neck fractures complicated with comminuted posterior wall at Department of Orthopaedics, Shenzhen Hospital, University of Chinese Academy of Sciences from February 2017 to December 2019. They were divided into 2 groups according to 2 fixation modes. There were 42 males and 16 females with an age of 48.5 (40.0, 55.3) years in CCS group of 58 cases subjected to fixation with 3 CCSs; there were 31 males and 20 females with an age of 47.0 (38.0, 53.0) years in DHS group of 51 cases subjected to fixation with DHS plus anti-rotation screw. The length of incision, operation time, intraoperative bleeding, weight-bearing time for the affected limb, visual analog scale (VAS), hip Harris score, and incidence of postoperative complications were compared between the 2 groups.Results:The comparison of preoperative general data between the 2 groups was not statistically significant, showing comparability between groups ( P>0.05). In the CCS group, the incision length [3.0 (2.9, 4.5) cm] and operation time [90.0 (73.8, 125.0) min] were significantly shorter than those in the DHS group [10.0 (9.0, 12.0) cm and 135.0 (110.0, 165.0) min], the intraoperative bleeding [40.0 (10.0, 100.0) mL] was significantly less than that in the DHS group [200.0 (150.0, 300.0) mL], the partial and complete weight-bearing durations of the affected limb [12.0 (12.0, 13.0) weeks and 24.0 (21.0, 25.0) weeks] were significantly longer than those in the DHS group [11.0 (10.0, 12.0) weeks and 19.0 (18.0, 20.0) weeks], and the perioperative VAS pain score [2.0 (2.0, 3.0) points] was significantly lower than that in the DHS group [5.0 (4.0, 6.0) points], but the incidence of follow-up complications [56.9% (33/58)] was significantly higher than that in the DHS group [33.3% (17/51)] (all P<0.05). There was no significant difference between the DHS group and the CCS group in the excellent and good rate of Harris hip score at one year after operation [94.1% (48/51) versus 91.4% (53/58)] ( P>0.05). Conclusions:In the treatment of femoral neck fractures complicated with comminuted posterior wall, DHS plus anti-rotation screw and 3 CCSs can both result in fine therapeutic outcomes but a relatively high incidence of complications at late follow-up. However, the former fixation mode can shorten the weight-bearing time for the affected limb and reduce complications but is more invasive than the latter fixation mode.

Tooth root morphogenesis involves two biological processes, root elongation and dentinogenesis, which are guaranteed by downgrowth of Hertwig's epithelial root sheath (HERS) and normal odontoblast differentiation. Ubiquitin-dependent protein degradation has been reported to precisely regulate various physiological processes, while its role in tooth development is still elusive. Here we show ubiquitin-specific protease 34 (USP34) plays a pivotal role in root formation. Deletion of Usp34 in dental mesenchymal cells leads to short root anomaly, characterized by truncated roots and thin root dentin. The USP34-deficient dental pulp cells (DPCs) exhibit decreased odontogenic differentiation with downregulation of nuclear factor I/C (NFIC). Overexpression of NFIC partially restores the impaired odontogenic potential of DPCs. These findings indicate that USP34-dependent deubiquitination is critical for root morphogenesis by stabilizing NFIC.
Cell Differentiation ; Female ; Morphogenesis ; NFI Transcription Factors ; Odontogenesis ; Tooth Root

Objective: To identify the risk factors for early fluid overload(FO)following repair in the pediatric patients with anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) complicated with moderate or severe left ventricular dysfunction (left ventricular ejection fraction [LVEF]<50%) and evaluate the effect on clinical outcomes. Methods: Forty-three pediatric patients with ALCAPA complicated with moderate or severe left ventricular dysfunction, aged 2-128 months, weighing 4.5-34.5 kg, with New York Heart Association Ⅲ or Ⅳ, undergoing ALCAPA repair, were enrolled in this study.The pediatric patients were divided into FO≥5% group (n=14) and FO<5% group (n=29) according to the FO developed within 24 h after operation. The pediatric Risk, Injury, Failure, Loss, and End-Stage Renal Disease criterion was used to diagnose acute kidney injury developed after operation. Factors including age, height, weight, preoperative LVEF, preoperative biomarkers, operative data, postoperative ventilation time, duration of intensive care unit(ICU)stay and related postoperative clinical outcome parameters were recorded.The risk factors of which P values were less than 0.05 would enter the multivariate logistic regression analysis to stratify the risk factors for FO≥5% developed within 24 h after operation.The effect of FO≥5% on postoperative severe acute kidney injury (Injury and Failure), ventilation time, duration of ICU stay and etc. was assessed. Results: Fourteen cases developed early postoperative FO≥5%, and the incidence was 33%.The results of the logistic regression analysis showed that lower preoperative LVEF was an independent risk factor for early postoperative FO≥5% (P<0.05). Compared with FO<5% group, the postoperative ventilation time and duration of ICU stay were significantly prolonged, the number of pediatric patients who developed pulmonary infection and required reintubation was increased, the number of pediatric patients in whom duration of ICU stay was more than 14 days was increased (P<0.05), and no significant change was found in the other parameters of clinical outcomes in FO≥5% group (P>0.05). Conclusion Lower preoperative LVEF is a risk factor for early postoperative FO in pediatric patients with ALCAPA complicated with a moderate or severe left ventricular dysfunction undergoing repair, and it is not helpful for clinical outcomes in pediatric patients when postoperative early FO≥5% occurs.

Objective To evaluate the feasibility of utilizing dose-volume histogram (DVH) prediction models of organs at risk (OARs) to deliver automatic treatment planning of prostate cancer.Methods The training set included 30 cases randomly selected from a database of 42 cases of prostate cancer receiving treatment planning.The bladder and rectum were divided into sub-volumes (Ai) of 3 mm in layer thickness according to the spatial distance from the boundary of planning target volume (PTV).A skewed normal Gaussian function was adopted to fit the differential DVH of Ai,and a precise mathematical model was built after optimization.Using the embedded C++ subroutine of Pinnacle scripa,ahe volume of each Ai of the remaining validation set for 12 patients was obtained to predict the DVH parameters of these OARa,ahich were used as the objective functions to create personalized Pinnacle script.Finalla,automatic plans were generated using the script.The dosimetric differences among the original clinical plannina,aredicted value and the automatic treatment planning were statistically compared with paired t-test.Results DVH residual analysis demonstrated that predictive volume fraction of the bladder and rectum above 6 000 cGy were lower than those of the original clinical planning.The automatic treatment planning significantly reduced the V70,V60,V50 of the bladder and the V70 and V60 of the rectum than the original clinical planning (all P＜0.05),the coverage and conformal index (CI) of PTV remained unchangea,and the homogeneity index (HI) was slightly decreased with no statistical significance (P＞ 0.05).Conclusion The automatic treatment planning of the prostate cancer based on the DVH prediction models can reduce the irradiation dose of OARs and improve the treatment planning efficiency.

Objective To observe the effect of a walking correcting tape on the kinematics and temporal-spatial indicators of gait after a stroke. Methods Thirty hemiplegic stroke survivors were randomly divided into a control group ( n=15) and a correcting tape group ( n=15) . In addition to their routine rehabilitation program, the control group received 30 minutes of walking training five times a week for 3 weeks with any necessary oral guidance and posture correction. The correcting tape group performed the same walking training assisted by a self-made walking correcting tape. Before and after the treatment, the kinematics and temporal-spatial indicators of both groups were quantified using three-dimensional gait analysis. Results After the treatment, the peak angles of hip and knee flex-ion were significantly higher in the taped group than in the control group and in the taped group before the treatment ( P≤0.05) . After the treatment, the walking speeds, stride frequencies and stride lengths of both groups were signifi-cantly better than before the treatment, but those of the former group were all significantly better than the latter ( P≤0.05 for both) . Conclusions Correcting tape can improve the peak angles of hip and knee flexion of hemiplegic legs and improve the walking capacity of stroke patients.

Aim This was to study the effects of hydroxysafflor yellow A(HYSA)on iNOS expression in rats following focal cerebral ischemia. Methods Rat cerebral ischemia-reperfusion injury was induced by middle cerebral artery occlusion. The expression levels of iNOS were examined using immunohistochemical method. The neurological outcome and the cerebral infarct area were evaluated. Results The expression levels of iNOS in HYSA groups were significantly lower than those in ischemic model group. Treatment with HYSA also decreased the cerebral infarct area and the neurological deficit score. Conclusion HYSA induced down regulation of iNOS expression, which may mediate the protective effect of HYSA on cerebral ischemia.