Fine particulate matter (FPM) is a major component of air pollution and has emerged as a significant global health concern owing to its adverse health effects. Previous studies have investigated the correlation between bone health and FPM through cohort or review studies. However, the effects of FPM exposure on bone health are poorly understood. This study aimed to investigate the effects of FPM on bone health and elucidate these effects in vitro and in vivo using mice. Micro-CT analysis in vivo revealed FPM exposure decreased bone mineral density, trabecular bone volume/total volume ratio, and trabecular number in the femurs of mice, while increasing trabecular separation. Histological analysis showed that the FPM-treated group had a reduced trabecular area and an increased number of osteoclasts in the bone tissue. Moreover, in vitro studies revealed that low concentrations of FPM significantly enhanced osteoclast differentiation. These findings further support the notion that short-term FPM exposure negatively impacts bone health, providing a foundation for further research on this topic.

Atherosclerosis is a major contributor to cardiovascular disease, characterized by inflammation and lipid accumulation in arterial walls, leading to plaque formation. Elevated low-density lipoprotein cholesterol is a primary risk factor for atherosclerosis. All-trans retinoic acid (ATRA), a metabolite of vitamin A, has demonstrated anti-inflammatory effects and potential in regulating vascular injury. 9-cisretinoic acid (9cRA) is an active metabolite of vitamin A and activates the retinoid X receptor. This study investigates whether potassium retinoate (PA9RA), a synthetic combination of ATRA and 9cRA, offers superior efficacy in treating atherosclerosis compared to established treatments such as clopidogrel and atorvastatin. Male ApoE -/- mice were fed a Western-type diet and treated with PA9RA, clopidogrel, or atorvastatin for 10 weeks. The body weight, organ weight, serum biochemistry, and histopathology, including atherosclerotic lesion area and liver steatosis were assessed. PA9RA treatment led to a significant reduction in body weight and inguinal fat, with the 45 mg/kg/day dose showing marked efficacy in decreasing atherosclerotic lesion size and ameliorating liver steatosis. Histopathological evaluation revealed decreased foam cell formation and improved liver histology in PA9RA-treated groups compared to controls. Notable side effects included epidermal hyperplasia and gastric hyperplasia at high doses of PA9RA. PA9RA exhibits superior efficacy over clopidogrel and atorvastatin in ameliorating atherosclerosis and fatty liver in ApoE –/–mice. This study highlights PA9RA's potential as a promising therapeutic agent for atherosclerosis. Further research is needed to elucidate its mechanisms of action and assess long-term safety and efficacy.

Purpose: Persistent postoperative stiffness is a common complication after arthroscopic rotator cuff repair (ARCR).We hypothesized that a subacromial steroid injection (SAI) may improve the early outcomes in patients with persistent stiffness without increasing steroid-associated complications. Therefore, we evaluated the effectiveness and safety of SAI in patients with persistent stiffness 3 months after ARCR. Methods: We retrospectively analyzed 300 ARCR cases performed between January 2012 and May 2014, in which repair integrity was confirmed at postoperative 3 months. Patients were divided into SAI and control groups. The SAI group received a single SAI (triamcinolone 40 mg and ropivacaine 52.5 mg) to address postoperative stiffness, with no additional SAI thereafter. The control group did not receive any injections until the final follow-up. Functional and radiological outcomes were compared between the two groups. Results: The mean follow-up period was 18.1±4.7 months (range, 12.1–37.2 months), with no difference between groups (p=0.731). At the time of injection, the range of motion was significantly lower in the SAI (all p＜0.001). However, functional outcomes were comparable between the two groups at 3 months after injection and the final follow-up (all p＞ 0.05). The healing failure rate at the final follow-up also did not differ between the SAI and control groups (14.9% vs. 13.2%, p=0.671). Conclusion This short-term follow-up study suggests that the administration of a single SAI to treat persistent stiffness at 3 months after ARCR may improve functional recovery without increasing the risk of healing failure.

Fine particulate matter (FPM) is a major component of air pollution and has emerged as a significant global health concern owing to its adverse health effects. Previous studies have investigated the correlation between bone health and FPM through cohort or review studies. However, the effects of FPM exposure on bone health are poorly understood. This study aimed to investigate the effects of FPM on bone health and elucidate these effects in vitro and in vivo using mice. Micro-CT analysis in vivo revealed FPM exposure decreased bone mineral density, trabecular bone volume/total volume ratio, and trabecular number in the femurs of mice, while increasing trabecular separation. Histological analysis showed that the FPM-treated group had a reduced trabecular area and an increased number of osteoclasts in the bone tissue. Moreover, in vitro studies revealed that low concentrations of FPM significantly enhanced osteoclast differentiation. These findings further support the notion that short-term FPM exposure negatively impacts bone health, providing a foundation for further research on this topic.

Atherosclerosis is a major contributor to cardiovascular disease, characterized by inflammation and lipid accumulation in arterial walls, leading to plaque formation. Elevated low-density lipoprotein cholesterol is a primary risk factor for atherosclerosis. All-trans retinoic acid (ATRA), a metabolite of vitamin A, has demonstrated anti-inflammatory effects and potential in regulating vascular injury. 9-cisretinoic acid (9cRA) is an active metabolite of vitamin A and activates the retinoid X receptor. This study investigates whether potassium retinoate (PA9RA), a synthetic combination of ATRA and 9cRA, offers superior efficacy in treating atherosclerosis compared to established treatments such as clopidogrel and atorvastatin. Male ApoE -/- mice were fed a Western-type diet and treated with PA9RA, clopidogrel, or atorvastatin for 10 weeks. The body weight, organ weight, serum biochemistry, and histopathology, including atherosclerotic lesion area and liver steatosis were assessed. PA9RA treatment led to a significant reduction in body weight and inguinal fat, with the 45 mg/kg/day dose showing marked efficacy in decreasing atherosclerotic lesion size and ameliorating liver steatosis. Histopathological evaluation revealed decreased foam cell formation and improved liver histology in PA9RA-treated groups compared to controls. Notable side effects included epidermal hyperplasia and gastric hyperplasia at high doses of PA9RA. PA9RA exhibits superior efficacy over clopidogrel and atorvastatin in ameliorating atherosclerosis and fatty liver in ApoE –/–mice. This study highlights PA9RA's potential as a promising therapeutic agent for atherosclerosis. Further research is needed to elucidate its mechanisms of action and assess long-term safety and efficacy.

Purpose: Persistent postoperative stiffness is a common complication after arthroscopic rotator cuff repair (ARCR).We hypothesized that a subacromial steroid injection (SAI) may improve the early outcomes in patients with persistent stiffness without increasing steroid-associated complications. Therefore, we evaluated the effectiveness and safety of SAI in patients with persistent stiffness 3 months after ARCR. Methods: We retrospectively analyzed 300 ARCR cases performed between January 2012 and May 2014, in which repair integrity was confirmed at postoperative 3 months. Patients were divided into SAI and control groups. The SAI group received a single SAI (triamcinolone 40 mg and ropivacaine 52.5 mg) to address postoperative stiffness, with no additional SAI thereafter. The control group did not receive any injections until the final follow-up. Functional and radiological outcomes were compared between the two groups. Results: The mean follow-up period was 18.1±4.7 months (range, 12.1–37.2 months), with no difference between groups (p=0.731). At the time of injection, the range of motion was significantly lower in the SAI (all p＜0.001). However, functional outcomes were comparable between the two groups at 3 months after injection and the final follow-up (all p＞ 0.05). The healing failure rate at the final follow-up also did not differ between the SAI and control groups (14.9% vs. 13.2%, p=0.671). Conclusion This short-term follow-up study suggests that the administration of a single SAI to treat persistent stiffness at 3 months after ARCR may improve functional recovery without increasing the risk of healing failure.

Background and Objectives: Cigarette smoking is a major risk factor for atherosclerosis.Nicotine, a crucial constituent of tobacco, contributes to atherosclerosis development and progression. However, evidence of the association between nicotine and neointima formation is limited. We aimed to evaluate whether nicotine enhances neointimal hyperplasia in the native epicardial coronary arteries of pigs after percutaneous coronary intervention (PCI) with drug-eluting stents (DES). Methods: After coronary angiography (CAG) and quantitative coronary angiography (QCA), we implanted 20 DES into 20 pigs allocated to 2 groups: no-nicotine (n=10) and nicotine (n=10) groups. Post-PCI CAG and QCA were performed immediately. Follow-up CAG, QCA, optical coherence tomography (OCT), and histopathological analyses were performed 2 months post-PCI. Results: Despite intergroup similarities in the baseline QCA findings, OCT analysis showed that the nicotine group had a smaller mean stent and lumen areas, a larger mean neointimal area, greater percent area stenosis, and higher peri-strut fibrin and inflammation scores than the no-nicotine group. In immunofluorescence analysis, the nicotine group displayed higher expression of CD68 and α-smooth muscle actin but lower CD31 expression than the no-nicotine group. Conclusions Nicotine inhibited re-endothelialization and promoted inflammation and NIH after PCI with DES in a porcine model.