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Effective management of malignant tumor-induced bone defects remains challenging due to severe systemic side effects, substantial tumor recurrence, and long-lasting bone reconstruction post tumor resection. Magnesium and its alloys have recently emerged in clinics as orthopedics implantable metals but mostly restricted to mechanical devices. Here, by deposition of calcium-based bilayer coating on the surface, a Mg-based composite implant platform is developed with tailored degradation characteristics, simultaneously integrated with chemotherapeutic (Taxol) loading capacity. The delicate modulation of Mg degradation occurring in aqueous environment is observed to play dual roles, not only in eliciting desirable osteoinductivity, but allows for modification of tumor microenvironment (TME) owing to the continuous release of degradation products. Specifically, the sustainable H2 evolution and Ca2+ from the implant is distinguished to cooperate with local Taxol delivery to achieve superior antineoplastic activity through activating Cyt-c pathway to induce mitochondrial dysfunction, which in turn leads to significant tumor-growth inhibition in vivo. In addition, the local chemotherapeutic delivery of the implant minimizes toxicity and side effects, but markedly fosters osteogenesis and bone repair with appropriate structure degradation in rat femoral defect model. Taken together, a promising intraosseous administration strategy with biodegradable Mg-based implants to facilitate tumor-associated bone defect is proposed.

Abstract Background Osteonecrosis of the femoral head (ONFH) often leads to the collapse of the femoral head, ultimately resulting in patients undergoing premature total hip arthroplasty (THA). The surgical hip dislocation (SHD) technique is a type of hip-preserving surgery aimed at delaying or avoiding THA. This study aims to evaluate the clinical efficacy of SHD techniques through femoral head fovea fenestration and impaction bone grafting for the treatment of non-traumatic ONFH. Methods A retrospective analysis was conducted on the clinical data of 39 patients (39 hips) with non-traumatic ONFH who underwent SHD for treatment from 2016 to 2017. The Harris hip score (HHS) and the minimum clinically important difference (MCID) are used to evaluate clinical outcomes, while radiographic evaluations are conducted using X-rays. Kaplan-Meier survival analysis defined clinical failure as further THA, and conducted univariate survival analysis and Cox regression analysis. Any complications were recorded. Results All patients were followed up for 24–72 months, with an average of (60 ± 13.0) months. At the last follow-up, based on the HHS, 25 patients (64.1%) reported excellent and good clinical outcomes. 29 patients (74.3%) achieved MCID. Imaging evaluation of the postoperative femoral head status showed that 6 cases improved, 20 cases remained stable, and 13 cases showed progressed. Out of 39 hips, 12 hips had postoperative clinical failure, resulting in a clinical success rate of 69.2%. Association Research Circulation Osseous (ARCO) stage, China-Japan Friendship Hospital (CJFH) classification, and postoperative crutch-bearing time are risk factors for clinical failure. Postoperative crutch-bearing time of less than 3 months is an independent risk factor for clinical failure. After surgery, there was one case of sciatic nerve injury and one case of heterotopic ossification. There were no infections or non-union of the greater trochanter osteotomy. Conclusion The SHD technique through the femoral head fovea fenestration and impaction bone grafting provides a safe and effective method for treating non-traumatic ONFH, with good mid-term clinical outcomes. ARCO staging, CJFH classification, and postoperative crutch-bearing time are risk factors that affect clinical outcomes after surgery and lead to further THA. Insufficient postoperative crutch-bearing time is an independent risk factor for clinical failure.

Osteoporotic fractures have become a common public health problem and are usually accompanied by chronic pain. Mg and Mg-based alloys are considered the next-generation orthopedic implants for their excellent osteogenic inductivity, biocompatibility, and biodegradability. However, Mg-based alloy can initiate aberrant activation of osteoclasts and modulate sensory innervation into bone callus resulting in postoperative pain at the sequential stage of osteoporotic fracture healing. Its mechanism is going to be investigated. Strontium hydrogen phosphate (SrHPO4) coating to delay the Mg-based alloy degradation, can reduce the osteoclast formation and inhibit the growth of sensory nerves into bone callus, dorsal root ganglion hyperexcitability, and pain hypersensitivity at the early stage. Liquid chromatography-mass spectrometry (LC-MS) metabolomics analysis of bone marrow-derived macrophages (BMMs) treated with SrHPO4-coated Mg alloy extracts shows the potential effect of increased metabolite levels of AICAR (an activator of the AMPK pathway). We demonstrate a possible modulated secretion of AICAR and osteoclast differentiation from BMMs, which inhibits sensory innervation and postoperative pain through the AMPK/mTORc1/S6K pathway. Importantly, supplementing with AICAR in Mg-activated osteoclasts attenuates postoperative pain. These results suggest that Mg-induced postoperative pain is related to the osteoclastogenesis and sensory innervation at the early stage in the osteoporotic fractures and the SrHPO4 coating on Mg-based alloys can reduce the pain by upregulating AICAR secretion from BMMs or preosteoclasts.

Brain alpha-tocopherol (αT) concentration was previously reported to be inversely associated with neurofibrillary tangle (NFT) counts in specific brain structures from centenarians. However, the contribution of natural or synthetic αT stereoisomers to this relationship is unknown. In this study, αT stereoisomers were quantified in the temporal cortex (TC) of 47 centenarians in the Georgia Centenarian Study (age: 102.2 ± 2.5 years, BMI: 22.1 ± 3.9 kg/m2) and then correlated with amyloid plaques (diffuse and neuritic plaques; DPs, NPs) and NFTs in seven brain regions. The natural stereoisomer, RRR-αT, was the primary stereoisomer in all subjects, accounting for >50% of total αT in all but five subjects. %RRR was inversely correlated with DPs in the frontal cortex (FC) (ρ = −0.35, p = 0.032) and TC (ρ = −0.34, p = 0.038). %RSS (a synthetic αT stereoisomer) was positively correlated with DPs in the TC (ρ = 0.39, p = 0.017) and with NFTs in the FC (ρ = 0.37, p = 0.024), TC (ρ = 0.42, p = 0.009), and amygdala (ρ = 0.43, p = 0.008) after controlling for covariates. Neither RRR- nor RSS-αT were associated with premortem global cognition. Even with the narrow and normal range of BMIs, BMI was correlated with %RRR-αT (ρ = 0.34, p = 0.021) and %RSS-αT (ρ = −0.45, p = 0.002). These results providing the first characterization of TC αT stereoisomer profiles in centenarians suggest that DP and NFT counts, but not premortem global cognition, are influenced by the brain accumulation of specific αT stereoisomers. Further study is needed to confirm these findings and to determine the potential role of BMI in mediating this relationship.

Modular multilevel converters (MMCs) are widely applied to medium and high voltage occasions. The total power consumption of the submodule (SM) and the maximum power consumption of power devices in the SM are related to the operating costs and lifetime of the MMC. Existing literature only considers total power loss optimization or maximal power consumption optimization in MMC’s SM. In this article, a reduced loss and extended lifetime power loss optimum control (RLEL-PLOC) is introduced to inject the first-best second harmonic circulation into the MMC’s arm current. Compared with the conventional power loss optimization control, the proposed control could decrease the maximal power consumption of the semiconductor devices without increasing the total loss of the SM. According to study results of the MMC, compared with the circulating current suppression control (CCSC) method, the total power consumption of the SM could be reduced by 4.2% and the maximal power dissipation in the SM could be reduced by 5.4% with RLEL-PLOC. PSCAD simulation and MMC prototype experiment are also carried out, and the research results verified the availability of the put forward RLEL-PLOC for MMCs.

Spermidine, a polyamine reported to extend lifespan and reduce the risk of age-related diseases, serves as a substrate for the post-translational modification hypusination. Here the authors report that EIF5A hypusination, which regulates mitochondrial protein synthesis, is reduced during non-alcoholic steatohepatitis (NASH), which can be prevented by spermidine to inhibit the progression of NASH in mice.

本研究旨在探討臺灣與馬來西亞教保服務人員，對幼兒性不當對待防治認知與實踐的表現及差異。首先訪談 2 位臺灣教保服務人員，根據訪談結果與相關文獻，初擬問卷 24 題，接著請 2 位臺灣、4 位馬來西亞學術與實務工作者進行專家審核以建立效度。隨後對 51位臺灣與 53 位馬來西亞教保服務人員進行預試，以項目分析、雙變數相關分析、信度分析、因素分析進行刪題，以 Cronbach α 進行信度考驗，形成 24 題正式問卷，之後對471 位臺灣與 353 位馬來西亞教保服務人員進行正式施測。研究結果發現：兩國教保服務人員，在幼兒性不當對待防治的認知與實踐存在差異；且臺灣的認知與實踐皆優於馬來西亞。根據研究結果，事後訪談 4 位教保服務人員，補充造成該結果的原因。本研究提出相關建議，供教育行政單位與未來相關研究參考。 This study examined the performances and differences between Taiwanese and Malaysian preschool educators in their cognition and practice of prevention and treatment of child sexual abuse, especially for preschoolers. We initially interviewed two Taiwanese preschool educators. Based on the interview results and related literature, a preliminary 24-item questionnaire was drafted, and then two Taiwanese and four Malaysian academics and practitioners were invited to participate in expert validity. A preliminary test was conducted on 51 Taiwanese and 53 Malaysian preschool educators. Through an item analysis, bivariate correlation analysis, reliability analysis, and factor analysis, some items in the questionnaire were deleted. A formal 24-item questionnaire was developed using Cronbach’s alpha tests for further reliability verification. Subsequently, a formal survey was conducted on 471 Taiwanese and 353 Malaysian preschool educators. The research results reveal that preschool educators in both countries showed differences between their cognition and practice in the prevention and treatment regarding child sexual abuse. In addition, Taiwanese preschool educators demonstrated a better performance than their Malaysian counterparts in both cognition and practice. According to the results of the study, four preschool educators were interviewed afterward to add to the reasons of such results. Suggestions for the promotion of preventing children’s sexual abuse were offered in terms of subjects, the combination of teaching and researching for university teachers, and future research.