Selenium modulates β‐cyfluthrin‐induced liver oxidative toxicity in rats

This study was designed to investigate the possibility of β‐cyfluthrin to induce oxidative stress and biochemical perturbations in rat liver and the role of selenium in alleviating its toxic effects. Male Wister rats were randomly divided into four groups of seven each, group I served as control, group II treated with selenium (200 µg/kg BW), group III received β‐cyfluthrin (15 mg/kg BW, 1/25 LD₅₀), and group IV treated with β‐cyfluthrin plus selenium. Rats were orally administered their respective doses daily for 30 days. The administration of β‐cyfluthrin caused elevation in lipid peroxidation (LPO) and reduction in the activities of antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD), glutathione S‐transferase (GST), glutathione peroxidase (GPx), and glutathione reductase (GR). A decrease in reduced glutathione (GSH) content was also observed. Liver aminotransferases (AST and ALT) and alkaline phosphatase (ALP) were decreased, whereas lactate dehydrogenase (LDH) was increased. Selenium in β‐cyfluthrin‐induced liver oxidative injury of the rats modulated LPO, CAT, SOD, GSH, GST, GPx, and GR. Also, liver AST, ALT, ALP, and LDH were maintained near normal level due to selenium treatment. It is concluded that selenium scavenges reactive oxygen species and render a protective effect against β‐cyfluthrin toxicity. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1323–1329, 2014.     

Temporal delimitation of the healing phases via monitoring of fracture callus stiffness in rats

The healing process consists of at least three phases: inflammatory, repair, and remodeling phase. Because callus stiffness correlates with the healing phases, it is suitable for evaluating the fracture healing process. Our aim was to develop a method which allows determination of callus stiffness in vivo, the healing time and the duration of the repair phase. The right femurs of 16 Wistar rats were osteotomized and stabilized with either more rigid or more flexible external fixation. Fixator deformation was measured using strain gauges during gait analysis. The strains were recalculated as the callus stiffness over the time course of healing, and the healing phases were identified based on stiffness thresholds. Our hypothesis was that stabilization with more flexible external fixation prolongs the repair phase, therefore resulting in an extended healing time. Confirming our hypothesis, the duration of the repair phase (rigid: approximately 15 days, flexible: approximately 41 days) and the healing time (rigid: approximately 27 days, flexible: approximately 62 days) were significantly longer for more flexible external fixation. Our method allows the quantitative detection of differences in the healing time and duration of the repair phase without multiple time‐point sacrifices, which reduces the number of animals in experimental studies. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:1589–1595, 2014.     

Carotid Artery Doppler Flow Pattern After Deep Hypothermic Circulatory Arrest in Neonatal Piglets

The mechanisms of cerebral injury after cardiac surgery in neonates are not clear. The aim of the study was the analysis of flow changes in the carotid artery of neonatal piglets after deep hypothermic circulatory arrest (DHCA). Eight neonatal piglets were connected to cardiopulmonary bypass (CPB) and underwent (i) cooling to 18°C core temperature within 30 min, (ii) DHCA for 90 min, and finally (iii) rewarming to 37°C after cross‐clamp release (60 min of reperfusion). The blood flow was measured in the left carotid artery by an ultrasonic flow probe before CPB (baseline; T₀), immediately after termination of reperfusion on CPB (T₁), 30 min later (T₂), and 60 min later (T₃). Additionally, the pulsatility index and the resistance index were calculated and compared. Finally, the relationship between the carotid artery flow and the corresponding pressure at each time‐point was compared. After termination of CPB (T₁), the mean carotid artery flow was reduced from 45.26 ± 2.58 mL/min at baseline to 23.29 ± 2.58 mL/min (P < 0.001) and remained reduced 30 and 60 min later (P < 0.001 vs. baseline). Both the pulsatility index and the resistance index were increased after termination of reperfusion, with the maximum occurring 30 min after CPB end. In conclusion, the carotid artery Doppler flow in neonatal piglets was reduced after DHCA, while the indices of pulsatility and resistance increased.     

天津市公立医疗卫生机构新生儿病房护士人力资源现状分析

目的：分析天津市公立医疗卫生机构新生儿病房护士人力资源现状。 方法：采用自行编制的天津市公立医疗卫生机构新生儿病 房护理人力资源调查问卷,对天津市二级及以上公立医疗卫生机构新生儿病房的护理管理者进行问卷调查。 结果：天津市共 21 所医 院开设新生儿病房,其中独立新生儿病房 13 个、新生儿病室 8 个。 独立新生儿病房共开设普通床位数 347 张、NICU 床位数 75 张,配 备护士 300 名;新生儿病室共开设普通床位 42 张,配备护士 59 名。 独立新生儿病房中,普通病房床护比和护患比分别为 1:0.37~1:1和 1:4.5~1:9,NICU 的床护比和护患比分别为 1:0.45~1:1.3、1:1.75~1:4.3。 独立新生儿病房护士和新生儿病室护士的职称、学历、工龄、年 龄等结构配置比较差异无统计学意义（P＞0.05）,主要以主管护师、本科学历、工龄 6~20 年、年龄 25~40 岁为主。 独立新生儿病房对院 内培训、院外线上培训及院外线下培训的重视程度优于新生儿病室（P<0.05）;独立新生儿病房论文发表篇数多于新生儿病室（ χ2 = 6.812,P=0.033）,两者课题完成项数比较差异无统计学意义（ χ2 =3.180,P=0.204）。结论：天津市公立医疗卫生机构新生儿病房护士人力 资源配置有待完善,其结构配置较为合理,但人员缺口较大,新生儿病房护士对新生儿护理相关培训及科研的重视程度有待提高,特 别是新生儿病室护士。 新生儿护理管理者应关注 NICU 护士和新生儿专科护士的培养,可从加大护理人才引入力度、优化新生儿专科 护理能力培训、重视新生儿专科护士培养等方面综合提升新生儿病房护士岗位胜任力,以促进天津市新生儿护理学科的高质量发展。     

硫氧还蛋白还原酶 TrxR2在颅脑损伤大鼠皮质的表达变化

目的：探究硫氧还蛋白还原酶2（TrxR2）在颅脑损伤大鼠皮质的动态表达变化。方法54只雄性 SD 大鼠,随机分为正常对照组（n =6）和颅脑损伤组（n =48）。颅脑损伤组采用改良的 Freeny＆#39;s 自由落体装置制作颅脑损伤大鼠模型,正常对照组不做处理。伤后1 h、3 h、6 h、12 h、24 h、3 d、7 d、14 d,采用实时荧光定量 PCR （quantitative real-time PCR,qRT-PCR）和Western blot 检测挫伤区周围皮质 TrxR2 mRNA 和蛋白的表达变化情况。结果 qRT-PCR 结果显示：皮质中 TrxR2 mRNA 颅脑损伤后1 h 表达增加,24 h 达到高峰,7 d 恢复正常;颅脑损伤组伤后1 h~3 d 各时间点 TrxR2 mRNA 表达明显高于正常对照组（均 P ＜0.05）。Western blot 检测显示：TrxR2蛋白在颅脑损伤后1 h 表达增加,24 h 达到高峰,14 d 恢复正常;颅脑损伤组1 h~7 d 各时间点 TrxR2蛋白表达高于正常对照组（均 P ＜0.05）。结论颅脑损伤后 TrxR2表达增多,提示 TrxR2作为一种急性应激反应蛋白参与颅脑损伤早期抗氧化应激反应。     

The Protective Effect of Rhizoma Dioscoreae Extract against Alveolar Bone Loss in Ovariectomized Rats via Regulating Wnt and p38 MAPK Signaling

Aim: The aim of this study was to evaluate the osteoprotective effect of aqueous Rhizoma Dioscoreae extract (RDE) on the alveolar bone of rats with ovariectomy-induced bone loss. Methods: Female Wistar rats were subjected to either ovariectomy or a sham operation (SHAM). The ovariectomized (OVX) rats were treated with vehicle (OVX) or RDE by oral gavage or with 17β-estradiol (E2) subcutaneously. After treatments, the bone mineral density (BMD), the three-dimensional bone architecture of the alveolar bone and the plasma biomarkers of bone turnover were analyzed to assess bone metabolism, and the histomorphometry of the alveolar bone was observed. Microarrays were used to evaluate gene expression profiles in alveolar bone from RDE-treated and OVX rats. The differential expression of genes was further analyzed using Ingenuity Pathway Analysis (IPA). The key findings were verified using real-time quantitative RT-PCR (qRT-PCR). Results: Our results showed that RDE inhibited alveolar bone loss in OVX rats. Compared to the OVX rats, the RDE-treated rats showed upregulated expression levels of 207 genes and downregulated expression levels of 176 genes in the alveolar bone. The IPA showed that several genes had the potential to code for proteins that were involved in the Wnt/β-catenin signaling pathway (Wnt7a, Fzd2, Tcf3, Spp1, Frzb, Sfrp2 and Sfrp4) and the p38 MAPK signaling pathway (Il1rn and Mapk14). Conclusion: These experiments revealed that RDE could inhibit ovariectomy-induced alveolar bone loss in rats. The mechanism of this anti-osteopenic effect in alveolar bone may be involved in the reduced abnormal bone remodeling, which is associated with the modulation of the Wnt/β-catenin and the p38 MAPK signaling pathways via gene regulation.