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991.
Zichen Hao Jun Li Bo Li Kareme D Alder Sean V Cahill Alana M Munger Inkyu Lee Hyuk-Kwon Kwon JungHo Back Shuogui Xu Min-Jong Kang Francis Y Lee 《Journal of bone and mineral research》2021,36(1):186-198
Smokers are at a higher risk of delayed union or nonunion after fracture repair. Few specific interventions are available for prevention because the molecular mechanisms that result in these negative sequelae are poorly understood. Murine models that mimic fracture healing in smokers are crucial in further understanding the local cellular and molecular alterations during fracture healing caused by smoking. We exposed three murine strains, C57BL/6J, 129X1/SvJ, and BALB/cJ, to cigarette smoke for 3 months before the induction of a midshaft transverse femoral osteotomy. We evaluated fracture healing 4 weeks after the osteotomy using radiography, micro-computed tomography (μCT), and biomechanical testing. Radiographic analysis demonstrated a significant decrease in the fracture healing capacity of smoking 129X1/SvJ mice. μCT results showed delayed remodeling of fracture calluses in all three strains after cigarette smoke exposure. Biomechanical testing indicated the most significant impairment in the functional properties of 129X1/SvJ in comparison with C57BL/6J and BALB/cJ mice after cigarette smoke exposure. Thus, the 129X1/SvJ strain is most suitable in simulating smoking-induced impaired fracture healing. Furthermore, in smoking 129X1/SvJ murine models, we investigated the molecular and cellular alterations in fracture healing caused by cigarette smoking using histology, flow cytometry, and multiplex cytokine/chemokine analysis. Histological analysis showed impaired chondrogenesis in cigarette smoking. In addition, the important reparative cell populations, including skeletal stem cells and their downstream progenitors, demonstrated decreased expansion after injury as a result of cigarette smoking. Moreover, significantly increased pro-inflammatory mediators and the recruitment of immune cells in fracture hematomas were demonstrated in smoking mice. Collectively, our findings demonstrate the significant cellular and molecular alterations during fracture healing impaired by smoking, including disrupted chondrogenesis, aberrant skeletal stem and progenitor cell activity, and a pronounced initial inflammatory response. © 2020 American Society for Bone and Mineral Research (ASBMR). 相似文献
992.
993.
Xiurong Kang Qinghu Wang Suriguga Ao Moxiyele Wenlin Bao Chaoliang zhao a 《中草药(英文版)》2023,15(2):337-342
Objective: To establish a high-performance liquid chromatographic method (HPLC) for the simultaneous determination of sixteen compounds from Artemisia ordosica.
Methods: HPLC was used to analyze 16 quality indicators of A. ordosica. The HPLC conditions were as follows: Agilent Eclipse Plus C18 column (250 mm × 4.6 mm, 5 μm) with acetonitrile (A)-water (B) as mobile phase, gradient elution: 0?10 min, 75%?65% B; 10?30 min, 65%?35 % B; and finally 30?40 min, 35%?15% B. The flow rate was 1.0 mL/min, the column temperature was 40 °C, the injection volume was 10 μL, and monitored by absorbance at 285 nm for compounds 1?10, 12 and 225 nm for compounds 11, 13?16.
Results: Under the selected experimental chromatographic conditions, compounds 1?16 showed good linearity (r > 0.9993) in a wide concentration range. Their average recoveries were 99.50%, 95.38%, 97.75%, 96.00%, 98.20%, 97.50%, 95.50%, 99.33%, 96.75%, 96.50%, 98.50%, 97.83%, 99.20%, 95.33%, 97.33% and 96.30%, respectively, and the RSD were 1.99%, 1.81%, 1.63%, 1.98%, 1.67%, 1.92%, 1.74%, 1.67%, 1.90%, 1.72%, 1.88%, 1.83%, 1.79%, 1.76%, 1.81% and 1.96%, respectively.
Conclusion: Based on the results of the HPLC analysis, it was concluded that p-hydroxycinnamic acid (1), O-hydroxycinnamic acid (2), coniferyl alcohol (5), 5,4''-dihydroxy-7,3''-dimethoxyflavanone (8), 5,4''-dihydroxy-7-methoxyflavanone (9), 5-hydroxy-7,4''-dimethoxyflavanone (12), dehydrofalcarindiol (13), arteordoyn A (14), dehydrofalcarinol (15) and capillarin (16) are best suited for the role of quality indicators of A. ordosica grown in different ecological environments. 相似文献
994.
Chun-xia Tian Ming-yue Li Xin-xin Shuai Feng Jiang Ya-lan Dong Yang Gui Zi-li Zhang Ren-jie Qin Zhen-yu Kang Lan Lin Alexey Sarapultsev Bin Wu Shan-shan Luo De-sheng Hu 《Phytotherapy research : PTR》2023,37(1):50-61
Myocardial infarction (MI) is one of the diseases with high fatality rate. Berberine (BBR) is a monomer compound with various biological functions. And some studies have confirmed that BBR plays an important role in alleviating cardiomyocyte injury after MI. However, the specific mechanism is unclear. In this study, we induced a model of MI by ligation of the left anterior descending coronary artery and we surprisingly found that BBR significantly improved ventricular remodeling, with a minor inflammatory and oxidative stress injury, and stronger angiogenesis. Moreover, BBR inhibited the secretion of Wnt5a/β-catenin pathway in macrophages after MI, thus promoting the differentiation of macrophages into M2 type. In summary, BBR effectively improved cardiac function of mice after MI, and the potential protective mechanism was associated with the regulation of inflammatory responses and the inhibition of macrophage Wnt5a/β-catenin pathway in the infarcted heart tissues. Importantly, these findings supported BBR as an effective cardioprotective drug after MI. 相似文献
995.
目的:对比分析两种髋关节镜技术治疗股骨髋臼撞击征(femoroacetabular impingement,FAI)的临床疗效和并发症。方法:回顾性分析2016年6月至2019年6月采用髋关节镜手术治疗并获得随访的48例FAI患者。根据手术方式的不同分为两组,Inside-out组,由中央到外周;Outside-in组,由外周到中央。Inside-out组24例,男14例,女10例,年龄(39.8±7.6)岁;Outside-in组24例,男13例,女11例,年龄(39.5±9.1)岁。两组患者年龄、性别、体质量指数、侧别、撞击类型、病程、随访时间比较差异无统计学意义。对两组术后髋关节改良Harris (modified Harris hip score,mHHS),非骨关节炎髋关节(nonarthritic hip score,NAHS)评分和术后并发症发生率进行比较。结果:两组患者术后髋关节功能评分mHHS和NAHS评分均较术前提高,但组间比较差异无统计学意义(P>0.05)。Inside-out组术后4例出现神经牵拉伤,3例医源性损伤;而Outside-in组仅1例神经牵拉伤。Inside-out组并发症发生率高于Outside-in组(16.7% vs 4.2%,χ2=5.400,P=0.020)。结论:Inside-out和Outside-in两种髋关节镜技术治疗FAI均可取得良好的临床效果,但相对于Inside-out技术,Outside-in技术术后并发症发生率低,针对符合适应证的患者可以优先选择。 相似文献
996.
997.
998.
Xuan-Mei Piao Ho Won Kang Pildu Jeong Young Joon Byun Hee Youn Lee Kyeong Kim Sung Phil Seo Won Tae Kim Jong-Young Lee Yun-Sok Ha Yung Hyun Choi Sung-Kwon Moon Seok Joong Yun Wun-Jae Kim 《Urologic oncology》2021,39(4):237.e21-237.e29
BackgroundThere is an increasing demand for prognostic immune biomarkers of cancer. The prognostic significance of immune markers has been shown for various cancers, but biomarkers of bladder cancer (BCa) have not been fully evaluated. To clarify the role of human leukocyte antigen DR alpha chain (HLA-DRA) in BCa development, we examined expression of HLA-DRA mRNA in tissue samples of non-muscle invasive bladder cancer (NMIBC) and muscle invasive bladder cancer (MIBC).Materials and MethodsTissues of 96 NMIBC, 43 MIBC and 59 controls comprising noncancerous BCa surrounding tissues were used to examine the expression of HLA-DRA gene by real-time polymerase chain reaction. The expression of up-stream genes regulating HLA-DRA were also measured to explain the role of HLA-DRA in BCa.ResultsPatients with high grade NMIBC showed higher expression of HLA-DRA than those with low grade NMIBC (P < 0.05). In addition, NMIBC patients who progressed to MIBC showed high expression of HLA-DRA mRNA. Kaplan-Meier analysis showed that NMIBC patients with low expression of HLA-DRA had better progression-free survival than those with high expression (P = 0.004). Moreover, the expression of genes regulating HLA-DRA varied in NMIBC and MIBC, indicating a different immunoregulation effect of HLA-DRA in both cancers.ConclusionsHigh expression of HLA-DRA in NMIBC patients has implications for patient stratification strategies, as well as for BCa tumor immunology. 相似文献
999.
1000.