纳米磷酸钙/氧化锆骨组织工程支架体内降解的实验研究

目的研究纳米磷酸钙/氧化锆骨组织工程支架材料体内降解特性,为进一步构建组织工程化纳米人工骨提供研究依据。方法制作兔股部肌袋,将灭菌的纳米磷酸钙/氧化锆骨组织工程支架材料植入肌袋内,在植入4周、8周、12周、16周时取材通过大体、组织学、扫描电镜观察材料降解情况,同时将材料取出后煅烧,测量残余无机物含量,判断降解的量,同时进行X线衍射实验,测量残余材料的组成。结果材料植入8周内降解较慢,生物力学强度减低不明显,12周时降解加速,材料强度明显减低,16周时新骨形成明显,降解残余材料分布于新形成的骨组织内部,X线衍射发现12周时材料内有羟基磷灰石成分出现,提示有新骨形成,16周时羟基磷灰石成分明显增多。结论纳米磷酸钙/氧化锆骨组织工程支架材料具有较好的降解性和生物相容性,具有诱导成骨作用,可作为骨组织工程的支架材料。     

Relationships between Dairy and Calcium Intake and Mental Health Measures of Higher Education Students in the United States: Outcomes from Moderation Analyses

Background: The prevalence of mental health concerns among university students in the United States (U.S.) continues to increase, while current treatments, including medication and counseling, present shortcomings. Higher dairy and calcium intakes are associated with protective effects on mental health; however, previous studies have focused on investigating singular relationships between dairy and calcium intakes and mental health measures. A more complex exploration of these relationships is warranted to better examine whether increasing dairy and calcium intakes could serve as an intervention to improve mental health. The present study sought to further characterize the relationships between dairy and calcium intake, perceived stress, and a variety of mental health measures using linear regression and moderation analyses. Methods: The present cross-sectional study involved students studying at three large U.S. universities, and data collection occurred from April to May 2020 when students were learning remotely due to the COVID-19 pandemic. An online survey comprising validated tools was distributed among students to assess dairy and calcium intake, perceived stress, anxiety, negative and positive moods, rumination, and resilience, sleep quality and duration, dietary risk, and physical activity. Results: A total of 1233 students completed the study. Higher dairy and calcium intake was coincident with lower perceived stress and higher positive mood scores, while higher calcium intake was also coincident with lower anxiety, rumination, and higher resilience scores. Additionally, as calcium intake increased, the relationship between perceived stress and anxiety and the relationship between perceived stress and negative mood weakened. Dairy intake did not have this effect. Conclusions: Based on the results, and considering that calcium is a shortfall nutrient, universities should consider initiating programs and public health campaigns to promote dairy and calcium intake among this population.     

基于回顾性队列的阿托伐他汀钙仿制药与原研药安全性和经济性评价及危险因素评估

目的:比较真实世界患者人群使用阿托伐他汀钙仿制药与原研药的安全性和经济性,评估影响阿托伐他汀钙安全性的危险因素。方法:回顾性收集某三甲医院2020年5月至2021年4月在急诊药房使用阿托伐他汀钙的所有患者的病例数据及药品费用数据,根据所用阿托伐他汀钙药物品种分为原研药及仿制药组进行统计分析。结果:原研药组与仿制药组患者肌酸激酶升高(2.45%vs.2.91%),以及丙氨酸氨基转移酶和/或门冬氨酸氨基转移酶升高的不良反应发生率(3.67%vs.5.83%),差异均无统计学意义(P>0.05)。多因素Logistic回归分析显示,高龄(OR=0.285,P=0.036)与肌酸激酶升高相关,感染(OR=0.366,P=0.026)、心梗(OR=0.303,P=0.048)与丙氨酸氨基转移酶和/或门冬氨酸氨基转移酶升高相关。仿制药的用药频度较原研药大幅提高(P<0.01),使用成本仅为原研药的1/30。结论:阿托伐他汀钙仿制药比原研药经济性更好,且安全性无显著差异。高龄、感染、心梗可能是服用阿托伐他汀患者发生相关不良反应的重要危险因素。     

硝苯地平对人牙龈成纤维细胞内Ca2+含量影响的激光共聚焦显微观察

目的:探讨硝苯地平对牙龈成纤维细胞内Ca2 含量的影响。方法:体外培养人牙龈成纤维细胞,钙离子指示剂F luo-3染色,激光扫描共聚焦显微镜下观察加入不同浓度硝苯地平(NIF终浓度分别为1200、32.4 ng/mL)后荧光亮度的变化。结果:硝苯地平能抑制DHP类钙通道激动剂Bay K8644引起的牙龈成纤维细胞内钙离子含量增加(P<0.05),不同浓度硝苯地平的作用之间没有剂量-效应关系。结论:硝苯地平引起牙龈增生可能与抑制牙龈成纤维细胞内Ca2 含量有关。     

Chaga mushroom-induced oxalate nephropathy that clinically manifested as nephrotic syndrome: A case report

RationaleThe Chaga mushroom (Hymenochaetaceae, Inonotus obliquus) is a fungus belonging to the Hymenochaetaceae family. It is parasitic on birch and other tree species. Chaga mushrooms are rich in various vitamins, minerals, and nutrients. Some people consider these mushrooms medicinal as they have been reported to suppress cancer progression through anti-inflammatory and antioxidant effects. However, recent studies have reported that excessive ingestion of Chaga mushrooms can cause acute oxalate nephropathy.Patient concernsA 69-year-old man who ingested Chaga mushroom powder (10–15 g per day) and vitamin C (500 mg per day) for the past 3 months developed acute kidney injury (AKI) with the clinical manifestations of nephrotic syndrome (NS).DiagnosisPathological findings showed focal acute tubular injury and the deposition of calcium oxalate crystals in the tubules. Light microscopy showed interstitial fibrosis and tubular atrophy, and electron microscopy showed the effacement of the foot processes in podocytes. Based on these results, the diagnosis was acute oxalate nephropathy accompanied by minimal change disease (MCD).InterventionsThe patient''s kidney function did not improve with supportive care, such as hydration and blood pressure control. Thus, we recommended hemodialysis and the administration of a high dose of steroids (intravenous hydrocortisone 500 mg twice a day for 3 days and oral prednisolone at 1 mg/kg).OutcomesThe patient''s kidney function recovered just 1 month after the start of treatment, and the MCD was completely remitted.LessonsIn cases of AKI with an unknown cause, it is important to closely observe the patient''s medication history, and it is recommended to perform kidney biopsy. Furthermore, this study showed that active dialysis and high-dose steroid treatment can restore kidney function in patients with AKI caused by acute oxalate nephropathy with MCD.     

A Sustainable Reuse of Agro-Industrial Wastes into Green Cement Bricks

The fabrication of bricks commonly consumes relatively high natural resources. To reduce the carbon footprint in the brick production industry, repurposing industrial wastes in the making of sustainable bricks is a recent trend in research and application. Local wastes, such as oil palm shell (OPS), palm oil fuel ash (POFA), and quarry dust (QD), are massively produced annually in the palm oil-exporting countries. Moreover, QD from mining industries is hazardous to both water and air quality. For better waste management in marching towards sustainability, these wastes should be given their second life as construction materials. Therefore, this paper investigates the possibility of incorporating agro-industrial wastes into the brick mixture by examining their properties by means of several standardized tests. For the mix design, a 100% replacement of coarse aggregate with OPS, 20% replacement of cement with POFA, 20% cement weight of limestone as admixture, and 0 to 50% replacements of fine aggregate with QD are experimentally considered. The optimum mix of these wastes is preliminarily determined by focusing on high compressive strength as an indicator. Other examinations include splitting tensile, flexural strength, water absorption, and efflorescence tests. Although the agro-industrial waste cement brick is 18% lower in the strength to weight ratio compared to that of conventional, it is observed that it has better late strength development due to its POFA pozzolanic properties. Moreover, the proposed green cement brick is further checked for compliance with several standards for feasible use in the construction industry. Financially, the cost for the brick with the new mix design is almost equivalent to that of conventional. Hence, this green cement brick is reasonable to be employed in the construction industry to promote material sustainability for better waste management.     

Investigation of Self-Healing Mortars with and without Bagasse Ash at Pre- and Post-Crack Times

Cracks in typical mortar constructions enhance water permeability and degrade ions into the structure, resulting in decreased mortar durability and strength. In this study, mortar samples are created that self-healed their cracks by precipitating calcium carbonate into them. Bacillus subtilus bacterium (10⁻⁷, 10⁻⁹ cells/mL), calcium lactate, fine aggregate, OPC-cement, water, and bagasse ash were used to make self-healing mortar samples. Calcium lactates were prepared from discarded eggshells and lactic acid to reduce the cost of self-healing mortars, and 5% control burnt bagasse ash was also employed as an OPC-cement alternative. In the presence of moisture, the bacterial spores in mortars become active and begin to feed the nutrient (calcium lactate). The calcium carbonate precipitates and plugs the fracture. Our experimental results demonstrated that cracks in self-healing mortars containing bagasse ash were largely healed after 3 days of curing, but this did not occur in conventional mortar samples. Cracks up to 0.6 mm in self-healing mortars were filled with calcite using 10⁻⁷ and 10⁻⁹ cell/mL bacteria concentrations. Images from an optical microscope, X-ray Diffraction (XRD), and a scanning electron microscope (SEM) were used to confirm the production of calcite in fractures. Furthermore, throughout the pre- and post-crack-development stages, self-healing mortars have higher compressive strength than conventional mortars. The precipitated calcium carbonates were primed to compact the samples by filling the void spaces in hardened mortar samples. When fissures developed in hardened mortars, bacteria became active in the presence of moisture, causing calcite to precipitate and fill the cracks. The compressive strength and flexural strength of self-healing mortar samples are higher than conventional mortars before cracks develop in the samples. After the healing process of the broken mortar parts (due to cracking), self-healing mortars containing 5% bagasse ash withstand a certain load and have greater flexural strength (100 kPa) than conventional mortars (zero kPa) at 28 days of cure. Self-healing mortars absorb less water than typical mortar samples. Mortar samples containing 10⁻⁷ bacteria cells/mL exhibit greater compressive strength, flexural strength, and self-healing ability. XRD and SEM were used to analyze mortar samples with healed fractures. XRD, FTIR, and SEM images were also used to validate the produced calcium lactate. Furthermore, the durability of mortars was evaluated using DTA-TGA analysis and water absorption tests.     

电压门控钙通道编码基因在孤独症谱系障碍中的研究进展

孤独症谱系障碍(ASD)是一类以社交障碍和兴趣狭窄为共同症状的广泛性神经发育障碍,发病机制主要与遗传因素有关,研究ASD易感基因是现今国内外医学领域的热点.电压门控钙离子通道(VGCC)对调控神经元动作电位的产生和神经递质的释放等至关重要.目前VGCC的10种亚型均被发现与ASD相关.本文主要综述了编码VGCC的10种...     

Experimental Study on Subgrade Material of Calcium Silicate Slag

Calcium silicate slag (CSS) is used as a secondary solid waste produced by aluminum extraction technology from high alumina fly ash, and its resource utilization has always been a key issue to be solved. In this study, CSS was used to replace a portion of fly ash (FA) to prepare a new inorganic binder stabilized material for road base. The unconfined compressive strength (UCS), phase composition, microstructure, durability and performance index of the base of the test section of the CSS pavement base material were studied. The results showed that with the increase in CSS content, the UCS of pavement base materials gradually increased. Under standard curing conditions, the UCS increased 6.90~17.24% after 7 days, and 7.90~28.95% after 28 days. The main reason was that as the hydration time increased from 7 d to 28 d, the hydration products C-A-S-H gel and C-S-H gel increased, the [SiO₄] polymerization degree increased, the crystal type changed, and the structure denser, which supported the good development of mechanical strength of CSS pavement base material. In addition, the research has been successfully applied to a pilot test in Hohhot, China. The freeze–thaw resistance, water stability and UCS of the CSS pavement base material were tested to meet the requirements of Chinese road construction standards, indicating that the application of CSS in pavement base is feasible.     

阿托伐他汀钙治疗老年脑动脉硬化的效果及对患者TC、TG、HDL-C、LDL-C水平的影响观察

目的 分析阿托伐他汀钙治疗老年脑动脉硬化的效果及对患者总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)水平的影响.方法 70例老年脑动脉硬化患者,随机分为对照组和观察组,各35例.对照组患者采取常规药物治疗,观察组在对照组基础上增加阿托伐他汀钙治疗.比较两组开始用药...