[Clinical and pathological features and differential diagnosis of fibro-osseous tumors and dysplasias]

Fibro-osseous lesions is a class of diseases with obvious similarities in clinical manifestations and pathological features, which has been attracting the attention of clinicians and pathologists. The latest WHO 2022 Classification (5th edition) included six of these diseases (cemento-osseous dysplasia, segmental odontomaxillary dysplasia, fibrous dysplasia, juvenile trabecular ossifying fibroma, psammomatoid ossifying fibroma and familial gigantiform cementoma) in the " fibro-osseous tumours and dysplasias ", and put forward new ideas on the diagnosis and treatment of these diseases. According to the latest WHO 2022 Classification (5th edition), the clinical and pathological features, diagnosis and differential diagnosis of these six diseases were described.

[Building world leading surgical oncology for gastric cancer in China]

This century has seen significant advances in the treatment and research of gastric cancer in China. Chinese scholars have made a series of key technological breakthroughs in minimally invasive surgery, perioperative treatment and artificial intelligence diagnosis. These world-leading clinical researches have improved treatment outcomes and reduced surgical trauma. Global surveillance of trends in cancer survival 2000-14 reported that survival of gastric cancer in China has significantly improved during the last 20 years. This paper reviews the research history of surgical oncology for gastric cancer in China, summarises the experience and attempts to explore the future direction.

Improved oxidation stability and crosslink density of chemically crosslinked ultrahigh molecular weight polyethylene using the antioxidant synergy for artificial joints

Vitamin E (VE) is currently an approved antioxidant to improve the oxidation stability of highly crosslinked ultrahigh molecular weight polyethylene (UHMWPE) insert used commercially in total joint arthroplasty. However, the decrease in crosslink density caused by VE reduces wear resistance of UHMWPE, showing an uncoordinated challenge. In this work, we hypothesized that D-sorbitol (DS) as a secondary antioxidant can improve the antioxidant efficacy of VE on chemically crosslinked UHMWPE. The combined effect of VE and DS on oxidation stability of UHMWPE was investigated at a set of controlled hybrid antioxidant content. The hybrid antioxidant strategy showed significantly synergistic enhancement on the oxidation stability of chemically crosslinked UHMWPE compared with the single VE strategy. More strikingly, the crosslink density of the blends with hybrid antioxidants stayed at a high level since DS is not sensitive to crosslinking. The relationships between oxidation stability, mechanical properties, crosslink density, and crystallinity were investigated, by which the clinically relevant overall performance of UHMWPE was optimized. This work provides a leading-edge design mean for the development of joint bearings.

Flexible Polydimethylsiloxane Composite with Multi-Scale Conductive Network for Ultra-Strong Electromagnetic Interference Protection

Highlights

A multi-scale conductive network was constructed in flexible PDMS/Ag@PLASF/CNT composite with micro-size Ag@PLASF and nano-size CNT. The PDMS/Ag@PLASF/CNT composite showed outstanding electrical conductivity of 440 S m-1 and superior electromagnetic interference shielding effectiveness of up to 113 dB. The PDMS/Ag@PLASF/CNT composites owned good retention (> 90%) of electromagnetic interference shielding performance even after subjected to a simulated aging strategy or 10,000 bending-releasing cycles.

Abstract

Highly conductive polymer composites (CPCs) with excellent mechanical flexibility are ideal materials for designing excellent electromagnetic interference (EMI) shielding materials, which can be used for the electromagnetic interference protection of flexible electronic devices. It is extremely urgent to fabricate ultra-strong EMI shielding CPCs with efficient conductive networks. In this paper, a novel silver-plated polylactide short fiber (Ag@PLASF, AAF) was fabricated and was integrated with carbon nanotubes (CNT) to construct a multi-scale conductive network in polydimethylsiloxane (PDMS) matrix. The multi-scale conductive network endowed the flexible PDMS/AAF/CNT composite with excellent electrical conductivity of 440 S m−1 and ultra-strong EMI shielding effectiveness (EMI SE) of up to 113 dB, containing only 5.0 vol% of AAF and 3.0 vol% of CNT (11.1wt% conductive filler content). Due to its excellent flexibility, the composite still showed 94% and 90% retention rates of EMI SE even after subjected to a simulated aging strategy (60 °C for 7 days) and 10,000 bending-releasing cycles. This strategy provides an important guidance for designing excellent EMI shielding materials to protect the workspace, environment and sensitive circuits against radiation for flexible electronic devices.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40820-022-00990-7.

[Diagnosis and differentiation diagnosis of primary temporomandibular joint cartilage and giant cell related tumor lesions]

Cartilage and giant cell-related neoplastic lesions originating in the temporomandibular joint region have similar clinical, imaging and pathological manifestations, making the diagnosis of these disorders challenging to varying degrees. Diagnostic findings can influence treatment procedures and a definitive pathological diagnosis is important for the prognosis of these conditions. In this article, we discuss the pathological diagnosis and differentiation of four benign cartilage and giant cell related tumors and tumor-like lesions that occur in the temporomandibular joint, namely synovial chondromatosis, tumoral calcium pyrophosphate deposition disease, pigmented villonodular synovitis and chondroblastoma, taking into account their clinical features and histological manifestations, with a view to providing a basis for clinical management.

[The impact of different comprehensive treatment models on patients with adenocarcinoma of esophagogastric junction based on propensity score matching: a single center cohort study]

Objective: To compare the prognostic influence and postoperative pathology of different comprehensive treatment models for adenocarcinoma of esophagogastric junction. Methods: Between January 2012 and December 2017, a total of 219 patients with adenocarcinoma of esophagogastric junction underwent surgery in Gastrointestinal Cancer Center, Peking University Cancer Hospital & Institute and were enrolled in this study. The clinicopathological data of these patients were collected. The patients were categorized into 3 groups according to different treatment models: surgery-first group, neoadjuvant chemotherapy (NAC) group and neoadjuvant chemoradiotherapy (nCRT) group. A trimatch propensity score analysis was applied to control potential confounders among the three groups by using R language software. A total of 7 covariates including gender, age, comorbidity, body mass index, clinical T stage, clinical N stage and Siewert type were included, and the caliper value was taken as 0.2. After matching, a total of 87 patients were included for analysis with 27 patients for each group. There were 82 males and 5 females, with a median age of 63 years (range: 38 to 76 years). The effect of preoperative treatment on postoperative tumor pathology among the three different comprehensive treatment models was explored by χ² test, ANOVA or Wilcoxon rank sum test. Mann-Whitney U test or χ² test were used to undergo pairwise comparisons. Kaplan-Meier method and Log-rank test were used to analyze the overall survival and progression-free survival. Results: The proportion of vascular embolism in the surgery-first group was 72.4% (21/29), which was significantly higher than NAC group (37.9% (11/29), χ²=6.971, P=0.008) and nCRT group (6.9% (2/29), χ²=26.696, P<0.01). The proportions of pathological T3-4 stage in nCRT group and NAC group were 55.2% (16/29) and 62.1% (18/29), respectively, which were significantly lower than the surgery-first group (93.1% (27/29), χ²=10.881, P=0.001; χ²=8.031, P=0.005). Compared with the NAC group (55.2% (16/29), χ²=6.740, P=0.009) and nCRT group (31.0% (9/29), χ²=18.196, P<0.01), the proportion of lymph node positivity 86.2% (25/29) were significantly higher in the surgery-first group. The 5-year overall survival rates were 62.1%, 68.6% and 41.4% for the surgery-first group, NAC group and nCRT group, respectively (χ²=4.976, P=0.083). The 5-year progression-free survival rates were 61.7%, 65.1% and 41.1% for the surgery-first group, NAC group and nCRT group, respectively. The differences in overall survival (χ²=4.976, P=0.083) and progression-free survival (χ²=4.332, P=0.115) among the three groups were nonsignificant. Conclusions: Postoperative pathology is significantly different among the three groups. Neoadjuvant chemotherapy and neoadjuvant chemoradiotherapy could decrease the proportions of vascular embolism, pathological T3-4 stage and lymph node positivity to achieve local tumor control. The prognosis of overall survival and progression-free survival are not significantly different among the three groups.

Propagation rules of shock waves in confined space under different initial pressure environments

In this paper, an initial pressure adjustable explosion vessel was developed, and the effect of negative pressure, positive pressure (0.2–1.8 atm) different initial ambient pressure on the explosive shock wave generated by the explosion of explosives was studied. The relationships between the specific impulse, shock wave velocity, the amount of explosive gas products and the ambient pressure were analyzed for different initial pressure environments. It was found that: the overpressure of the blast shock wave decreases with the initial ambient pressure of the explosion, and there exists a negative pressure environment with a dramatic pressure decrease near 0.6 atm, defined as the super-sensitive negative pressure P_cr. The propagation velocity of an explosive wave increases with a decrease in the ambient pressure, and the propagation velocity at a pressure of 1.8 atm is four times less than the velocity at a pressure of 0.2 atm. The production of explosive gas products did not change. The greater the initial pressure of the environment where the explosive is located, the smaller the ratio of the gas generated by the explosion to the initial force gas in the explosion vessel is, and the greater the impact on the propagation of shock waves is. The maximum attenuation of the first specific impulse i₁ is 72.97% and the maximum attenuation of the second specific impulse i₂ is 72.39%. The experiments provide reference data for high-altitude military confrontation, high-altitude weapons and ammunition development, and deep-earth protection engineering.

Reorganization of Hydrogen Bonding in Biobased Polyamide 5,13 under the Thermo-Mechanical Field: Hierarchical Microstructure Evolution and Achieving Excellent Mechanical Performance

The hierarchical microstructure evolution of an emerging biobased odd-odd polyamide 5,13 (PA5,13) films under the thermo-mechanical field, stepping from hydrogen bond (H-bond) arrangement to the crystalline morphology, has been investigated systematically. It is found that the reorganization of H-bonds under the thermo-mechanical field plays a crucial role in the crystallization of PA5,13. Especially, it is revealed that the crystallization process under the thermo-mechanical field develops along the chain axis direction, while lamellar fragmentation occurs perpendicular to the chain axis. Consequently, a stable and well-organized H-bond arrangement and lengthened lamellae with significant orientation have been constructed. Laudably, an impressive tensile strength of about 500 MPa and modulus of about 4.7 GPa are thus achieved. The present study could provide important guidance for the industrial-scale manufacture of high-performance biobased odd-odd PAs with long polymethylene segment in the dicarboxylic unit combined with a large difference between the polymethylene segments in the dicarboxylic and diamine units.

Nanotopographical 3D-Printed Poly(ε-caprolactone) Scaffolds Enhance Proliferation and Osteogenic Differentiation of Urine-Derived Stem Cells for Bone Regeneration

3D-printing technology can be used to construct personalized bone substitutes with customized shapes, but it cannot regulate the topological morphology of the scaffold surface, which plays a vital role in regulating the biological behaviors of stem cells. In addition, stem cells are able to sense the topographical and mechanical cues of surface of scaffolds by mechanosensing and mechanotransduction. In our study, we fabricated a 3D-printed poly(ε-caprolactone) (PCL) scaffold with a nanotopographical surface and loaded it with urine-derived stem cells (USCs) for application of bone regeneration. The topological 3D-printed PCL scaffolds (TPS) fabricated by surface epiphytic crystallization, possessed uniformly patterned nanoridges, of which the element composition and functional groups of nanoridges were the same as PCL. Compared with bare 3D-printed PCL scaffolds (BPS), TPS have a higher ability for protein adsorption and mineralization in vitro. The proliferation, cell length, and osteogenic gene expression of USCs on the surface of TPS were significantly higher than that of BPS. In addition, the TPS loaded with USCs exhibited a good ability for bone regeneration in cranial bone defects. Our study demonstrated that nanotopographical 3D-printed scaffolds loaded with USCs are a safe and effective therapeutic strategy for bone regeneration.

[The long-term efficacy of left cardiac sympathetic denervation in long QT syndrome]

Objective: To investigate the long-term efficacy and safety of left cardiac sympathetic denervation(LCSD) for long QT syndrome(LQTS) patients with either recurrence on drug therapy intolerance/refusal. Methods: This study was a retrospective cohort study. The cases selected from 193 patients with LQTS who were enrolled in the Chinese Channelopathy Registry Study from November 1999 to November 2012. This study selected 28 LQTS patients with either recurrence on drug therapy intolerance/refusal and underwent LCSD surgery in the Peking University People's Hospital or Beijing Tongren Hospital. The patients were allocated into 3 groups: high-risk group(n=13, baseline QTc ≥550 ms or symptomatic in the first year of life or highly malignant genetics); intermediate-risk group(n=10, 500 ms≤baseline QTc<550 ms, symptomatic after the first year and without highly malignant genetics); low-risk group(n=5, baseline QTc<500 ms, symptomatic after the first year and without highly malignant genetics). LCSD was performed with the traditional supraclavicular approach or video assisted thoracoscopic surgery (VATS). Patients were regularly followed up until 20 years after the surgery. Data were collected before and 1 year after surgery and at the last follow-up. Patients' electrocardiograph(ECG), cardiac events and surgery-related complications were recorded. Kaplan-Meier survival analysis was used to determine the cardiac event-free survival based on different risk stratification and genotypes. Results: A total of 28 LQTS patients, aged 20.5 (15.0, 37.5) and underwent LCSD surgery, were enrolled in this study, including 23(82.1%) women. There were 11(39.3%) patients treated with traditional approach while 17(60.7%) with VATS-LCSD. There were 19(67.9%) patients had positive genetic test results, including 4 LQT1, 12 LQT2, 1 LQT1/LQT2 mixed type, and 2 Jervell-Lange-Nielsen (JLN) syndrome. The median follow-up period was 189.3(138.7, 204.9) months. The dropout rate was 10.7%(3/28) while 3 patients in the intermediate-risk group were lost to follow-up. Horner syndrome occurred in 1 patient (in the high-risk group). Sudden cardiac deaths were observed in 3 (12.0%) patients (all in the high-risk group), and 12 patients (48.0%) had syncope recurrences (2 in low-risk group, 3 in intermediate-risk group and 7 in high-risk group). A significant reduction in the mean yearly episodes of cardiac events was observed, from (3.5±3.3) before LCSD to(0.2±0.1) at one year after LCSD and (0.5±0.8) at last follow up(P<0.001). The mean QTc was shortened from (545.7±51.2)ms before the surgery to (489.0±40.1)ms at the last follow-up (P<0.001). Among the 20 patients with basic QTc ≥500 ms and completing the follow-up, the QTc intervals of 11(55.0%) patients were shortened to below 500 ms. The event free survival rates for any cardiac events after LCSD decreased sequentially in the low-, intermediate- and high-risk groups, and the difference was statistically significant (χ²=7.24, log-rank P=0.026). No difference was found in the event free survival rates among LQT1, LQT2 and undefined gene patients (χ²=5.20, log-rank P>0.05). Conclusions: LCSD surgery can reduce the incidence of cardiac events and shorten the QTc interval in patients with LQTS after the long-term follow-up. LCSD surgery is effective and safe for patients with LQTS ineffective or intolerant to drug therapy. However, high-risk patients are still at a high risk of sudden death after surgery and should be actively monitored and protected by combined therapies.