高效液相色谱-串联质谱法测定猪肉中可的松和氢化可的松残留量的不确定度评价

评定超高效液相色谱-串联质谱法测定猪肉中可的松和氢化可的松残留量的不确定度。以本单位自建方法XCZY-051《动物源食品中克仑特罗等51种兴奋剂的检测方法液相色谱-串联质谱法》为基础,结合CNAS-GL006《化学分析中的不确定度评估指南》,建立数学模型,以猪肉中检出率最高的内源性兴奋剂可的松和氢化可的松为例分析不确定度来源并计算各不确定度得到的合成标准不确定度。当样品中可的松含量为3.386 μg/kg时,其扩展不确定度为0.4374 μg/kg(k=2);当氢化可的松含量为7.866 μg/kg时,其扩展不确定度为0.9690 μg/kg(k=2)。本方法的不确定度来源主要来自样品回收率、重复性、标准溶液配制和曲线拟合。     

Protective effect of low dose of hydrocortisone on the liver in LPS attack rats

AIM:To study the effect of different dosage of hydrocortisone on the liver in lipopolysaccharides(LPS) attack rats.METHODS:The model of LPS attack rats was established,and different doses of hydrocortisone were given to the rats. ALT and AST levels in rat plasma were tested,and the histology of rat liver was observed by microscope. RESULTS:ALT and AST levels were high in LPS group and had significant difference compared with the normal control group. ALT level in low dose(LD) group had no significant difference compared with the normal control group. The pathological change in the liver was obviously congested in high dose(HD) group and LPS group,many inflammatory cells were infiltrated. The change of liver in LD group was slight. CONCLUSION:Low dose hydrocortisone may have the protectiive effect on liver in LPS attack rats. High dose and middle dose of hydrocortisone have no effects.     

高效液相色谱测定复方聚维碘凝胶中氢化可的松的含量

采用高效液相色谱法（HPLC）测定复方聚维酮碘凝胶中氢化可的松的含量。以C18（4.6mm×250mm，5μm）为色谱柱，乙腈-甲醇-醋酸铵（20：45：35）为流动相，流速1mL／min，检测波长240nm，柱温37℃。结果显示：氢化可的松在0．025～0．122mg／mL范围内呈良好的线性关系（r=0．9993），回收率为96．06％，相对标准偏差（RSD）为0．45％。试验表明，采用高效液相色谱法测定复方聚维酮碘凝胶中氢化可的松的含量灵敏、快速、准确，可用于该复方制剂的质量控制或检验分析。     

桑椹素对氢化可的松致老龄阳虚模型小鼠的影响

桑椹素是以桑椹为主要成分的保健药品。将ICR雄性老龄小鼠随机分为正常组、模型组,以及桑椹素低、中、高剂量组(0.1,0.2,0.4 g/kg)和补肾填精丸组(0.35 g/kg),除正常组外各组均肌注氢化可的松造模,21 d后测定小鼠肝组织三磷酸原苷酶(Na+-K+-ATPase,Ca2+-Mg2+-ATPase)、超氧化物歧化酶(SOD)活性,以及还原型谷胱甘肽(GSH)、丙二醛(MDA)、丙酮酸、甘油三酯(TG)含量和血清SOD、GSH、MDA的水平变化情况,同时通过光镜观察小鼠肝脏组织结构病理变化。结果表明,以0.2、0.4 g/kg剂量桑椹素灌胃可显著提高模型小鼠肝组织ATP酶活性和降低丙酮酸、TG含量,还可提高抗氧化剂SOD、GSH水平,降低脂质过氧化物MDA含量,减轻氢化可的松引起的肝细胞浊肿、脂肪变性等病理变化。桑椹素对老龄阳虚模型小鼠肝脏具有明显的保护作用,其作用机制可能是通过促进糖、脂的氧化代谢提供充足的ATP,提高肝组织ATP酶活性;同时还可提高阳虚模型小鼠血清和肝脏中的SOD、GSH水平,清除体内自由基,以减轻其对肝细胞的损害,降低能量代谢障碍。     

氢化可的松对小鼠T淋巴细胞增殖的抑制作用

[目的]探讨氢化可的松对小鼠T淋巴细胞增殖功能的影响。[方法]用淋巴细胞分离液无菌制备小鼠脾淋巴细胞,于RPMI1640的完全培养基中加入ConA后进行转化。用流式细胞仪检测T细胞活化分子CD25和CD69及其共表达率。将转化的淋巴细胞分成不加氢化可的松的对照组和加入不同浓度的氢化可的松组,在各时间点取样计数,绘制其生长曲线。[结果]经ConA刺激3 d的T细胞上CD25和CD69分子及其共表达率最高,分别达73.5%、58%和32%。生长曲线显示,各组细胞在加氢化可的松后第2 d达到对数生长期,10-5、10-6、10-7mol/L浓度的氢化可的松对活化小鼠T淋巴细胞增殖都有抑制作用,但各浓度组间无显著差异（P〉0.05）,而与对照组相比有显著差异（P〈0.05）。[结论]在一定的浓度范围内氢化可的松对小鼠T淋巴细胞的增殖具有抑制作用,这为细胞移植免疫耐受的诱导提供了试验依据。     

酒精阳性乳牛血清皮质醇含量变化及其与代谢关系的探讨

本文通过酒精阳性乳牛与阴性乳牛血清中皮质醇，蛋白质及其代谢产物尿素氮，血糖和游离脂酸（ＦＦＡ）的测定，发现在阳性牛血中皮质醇含量的消涨规律的同时，出现阳性牛血糖升高，蛋白质降低，尿素氮升高，ＦＦＡ升高。结果表明，酒精阳性乳牛体内糖，脂质和蛋白质代谢发生了变化。这个变化与皮质醇等激素消涨有直接关系，为研究酒精阳性乳的发生机理提供了可靠的依据。     

Evaluation of pressor sensitivity to norepinephrine infusion in dogs with iatrogenic hyperadrenocorticism. Pressor sensitivity in dogs with hyperadrenocorticism

Hypertension is a common complication of canine hyperadrenocorticism. Increased pressor sensitivity to endogenous catecholamines is currently believed to be the main mechanism involved in the development of hypertension in human hyperadrenocorticism. The aim of this study was to evaluate pressor sensitivity to norepinephrine in dogs after induction of iatrogenic hyperadrenocorticism (I-HAC) by serial arterial blood pressure measurements during infusions of increasing dose rates of norepinephrine (0.1, 0.15, 0.2, 0.3, 0.4, 0.6, and 0.8 microg/kg/min) in eight dogs with I-HAC and eight control dogs. Systolic, diastolic, mean blood pressure and heart rate measurements were recorded. The changes in these parameters between the two groups of dogs were compared. Dogs in the I-HAC group had a more pronounced pressor response to norepinephrine infusions than control dogs since the infusions had to be stopped in seven of the dogs due to severe hypertension (>240 mmHg). The mean maximum tolerated dose rate in the control group was 0.6 microg/kg/min with a standard error of 0.0 and 0.34 microg/kg/min with a standard error of 0.08 in the I-HAC group. The study demonstrated the presence of increased pressor sensitivity to norepinephrine in dogs with I-HAC.     

Changes of cortisol content in plasma and hippocampus after focal cerebral ischemia-reperfusion in rats

AIM: To investigate the relationship between glucocorticoid (Gc) and injury of hippocampus neurons and the effect of Gc on dementia episode after cerebral ischemia-reperfusion. METHODS: The rat model of middle cerebral artery occlusion (MACO) was established. Cortisol contents in hippocampus and plasma of the model rats were examined by means of the radioimmunoassay at 2 h, 6 h, 12 h, 24 h after reperfusion. RESULTS: The levels of cortisol content in model group were significantly higher than those in sham group and normal group both in hippocampus and plasma. The highest cortisol content was observed at 6 hours after reperfusion. HE staining showed that the impairment of hippocampus neurons was aggravated progressively with reperfusion interval elongating. CONCLUSION: The increased cortisol in hippocampus and plasma, after 2 h cerebral ischemia and 24 h reperfusion, could aggravate the injury of hippocampus neurons and lead to dementia post stroke.     

The influence of anesthesia and means of postoperative pain control on T lymphocyte subtypes of blood in patients with rectal cancer

AIM: To evaluate the influence of anesthesia and different means of postoperative pain control on the T-lymphocyte during the perioperative period in patients with rectal cancer.METHODS: 40 adult patients, aged 65 or older, of American Society of Anesthesiologists (ASA) class 2-3 were divided into two groups according to the type and means of postoperative pain managements. Group Ⅰ (n=20) received intravenous anesthesia and patient controlled analgesia(PCA), fentanyl (13 μg/kg) for post pain; group Ⅱ (n=20) received intravenous anesthesia plus lumber epidural anesthesia and epidural PCA of morphine 5 mg plus ropivacaine 100 mg for post operative pain. Blood samples from internal jugular vein were obtained before surgery, at the completion of surgery and 24, 48, and 120 h post surgery for detecting CD3⁺, CD4⁺, CD4/CD8 counts of peripheral T-lymphocytes. In addition, blood cortisol level and pain intensity were assessed by visual analogue score (VAS)at each time point. RESULTS: Baseline(before anesthesia) values of CD3⁺,CD4⁺, CD4/CD8 in patients were messured and there was a significant decrease of all these values from completion of surgery to 48 h after surgery in both groups (P<0.01). However, group Ⅱ showed a higher CD4⁺ at 48 h, higher CD3⁺,CD4⁺, CD4/CD8 at 120 h post surgery than group Ⅰ (P<0.05). Patients in both groups obtained good pain relief post surgery,but VAS in group Ⅱ were significantly lower than those in group Ⅰ at 24 and 48 h post surgery (P<0.01). Compared with baseline, blood cortisol levels in both groups increased markedly at completion of surgery, and at 24, 48 h after surgery (P<0.01),while the increased cortisol level in group Ⅱ at completion of surgery and 24 h after surgery was less than that in group Ⅰ (P<0.05).CONCLUSION: Combined intravenous anesthesia with lumber epidural anesthesia appears to reduce the perioperative stress response and exerts less negative effects on the T-lymphocytes, suggesting that such a means of anesthesia might be more suitable to the elderly patients with rectal cancer.     

Effects of hypoxia inhalation therapy on the number of eosinophil and CD4+T-lymphocyte in remission stage in asthmatic guinea pigs

AIM:To explore the mechanism underlying the therapeutic effects of hypoxia inhalation on asthma. METHODS:Guinea pigs were randomized into the normal group(NG), asthmatic group(AG) and the hypoxia inhalation-treated group(HITG). The model of asthma was established in the latter two groups through sensitization and induction with 10% ovalbumin(OA) and 1% OA, respectively. The animals in HITG were treated with hypoxia inhalation (13.0%±0.5% O₂/N₂ mixed gas). The content of serum cortisol, the number of eosinophils(EOS) and percentage of hypodense eosinophils(HEOS) in bronchoalveolar lavage fluid(BALF),the number of CD₄⁺T-lymphocyte in peripheral blood(PB) and the tension of airway muscle were determined. RESULTS:(1)The content of serum cortisol was significantly higher in NG and HITG than in AG(P＜0.01); (2)The number of EOS and percentage of HEOS in BALF was significantly lower in HITG than in AG(P＜0.01); (3) The number of CD₄⁺T-lymphocyte in PB was significantly higher in AG than in HITG(P＜0.01).CONCLUSION:After treatment with hypoxia inhalation, the content of serum cortisol in asthmatic guinea pigs was significantly increased to result in marked decreased of the number of EOS, the percentage of HEOS in BALF, and the number of CD₄⁺T-lymphocyte in PB, thus result in the tension of airway muscle and alleviation of the airway hyperresponsiveness. All these may be beneficial to preventing the relapse of asthma.