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101.
Background and Purpose
To determine the minimally effective dose of cannabidiolic acid (CBDA) that effectively reduces lithium chloride (LiCl)-induced conditioned gaping reactions (nausea-induced behaviour) in rats and to determine if these low systemic doses of CBDA (5–0.1 μg·kg−1) relative to those of CBD could potentiate the anti-nausea effects of the classic 5-hydroxytryptamine 3 (5-HT3) receptor antagonist, ondansetron (OND).Experimental Approach
We investigated the efficacy of low doses of CBDA to suppress acute nausea, assessed by the establishment of conditioned gaping to a LiCl-paired flavour in rats. The potential of threshold and subthreshold doses of CBDA to enhance the reduction of nausea-induced conditioned gaping by OND were then determined.Key Results
CBDA (at doses as low as 0.5 μg·kg−1) suppressed nausea-induced conditioned gaping to a flavour. A low dose of OND (1.0 μg·kg−1) alone reduced nausea-induced conditioned gaping, but when it was combined with a subthreshold dose of CBDA (0.1 μg·kg−1) there was an enhancement in the suppression of LiCl-induced conditioned gaping.Conclusions and Implications
CBDA potently reduced conditioned gaping in rats, even at low doses and enhanced the anti-nausea effect of a low dose of OND. These findings suggest that combining low doses of CBDA and OND will more effectively treat acute nausea in chemotherapy patients. 相似文献102.
Andrea LA?TOVKOVá Pavlina KLUSá?KOVá Zdenka FENCLOVá Vincent BONNETERRE Daniela PELCLOVá 《Industrial health》2015,53(6):562-568
The objective of this study is to describe a case-series of potassium aluminium
tetrafluoride (KAlF4)-induced occupational asthma (OA) and/or occupational
rhinitis (OR). The study involves five patients from a heat-exchanger production line who
were examined (including specific inhalation challenge tests) for suspected OA and/or OR
caused by a flux containing almost 100% KAlF4 − with fluorides’ workplace air
concentrations ranging between 1.7 and 2.8 mg/m3. No subject had a previous
history of asthma. All five patients had a positive specific challenge test (three
patients were diagnosed with OA alone, one with OR and one with both OR and OA). At the
follow-up visit, after three years on average, all patients needed permanent
corticosteroid therapy (four topical, one oral). After elimination from the exposure, only
one of the observed subjects gave an indication of an improvement, two subjects stabilized
and two worsened. Our case series focuses on the correlation between patients’ exposure to
fluorides in air-conditioner production and the subsequent occurrence of OR/OA. Currently,
it is uncertain whether these OR/OA were caused by hypersensitivity or irritation. 相似文献
103.
104.
目的:探讨加味桂枝人参汤(MGD)溶液对胰岛素抵抗(IR)HpeG-2细胞模型的保护作用及机理。方法:成功复制HepG2细胞IR模型后,采用MGD溶液进行干预,并与罗格列酮进行对照,观察细胞形态学变化、各孔细胞的葡萄糖消耗量、细胞的数目与活力。结果:MGD对模型细胞的增殖并无明显影响(P0.05),但可以增加其葡萄糖消耗量(P0.01),与西药组比较无显著性差异(P0.05)。结论:中药MGD与罗格列酮具有同等的改善模型细胞IR的作用,可能与其增加HepG2细胞的葡萄糖消耗量,促进葡萄糖的摄取有关。 相似文献
105.
目的:建立UPLC-MS-MS同时测定大鼠血浆中2,3,5,4'-四羟基二苯乙烯-2-O-β-D-葡萄糖苷,1-脱氧野尻霉素和决明子苷、红镰霉素龙胆二糖苷、橙黄决明素、甲基钝叶决明素、白藜芦醇的分析方法,研究大鼠服用滋肾清肝代平方后的药代动力学特征。方法:采用Waters Acquity UPLC BEH C18色谱柱,流动相0.1%甲酸水溶液-乙腈梯度洗脱,采用电喷雾电离源,扫描方式为多反应离子监测。结果:7种成分在大鼠血浆中线性关系良好,提取回收率94.83%~106.58%,日内、日间精密度和准确度良好。7种成分在模型组大鼠中的药时曲线下面积、末端半衰期、达峰时间、清除率、表观分布容积、药峰浓度分别为(326.65±26.66)μg·L-1·h-1,(3.64±1.69)h,0.33 h,(60.56±5.32)L·h-1·kg-1,(325.13±167.18)L·kg-1,(169.25±18.02)μg·L-1。结论:该方法特异、快速、准确、灵敏,可用于滋肾清肝代平方在大鼠体内的药动学研究。 相似文献
106.
目的: 研究通莲汤对胃癌MGC803细胞形态、生长周期的调节作用及细胞核转录因子κB(NF-κB)信号通路的影响,以探讨该方抑制胃癌细胞增殖的机制。 方法: 将MGC803细胞以1×104个细胞/孔的密度接种于96孔细胞培养板,以含5%胎牛血清DMEM培养液培养,37 ℃,5%饱和湿度的CO2培养箱孵育,细胞贴壁24 h,分别加入浓度为25~800 mg·L-1倍比梯度的通莲汤提取液,以10~160 mg·L-1倍比浓度的氟脲嘧啶为阳性对照组,孵育48 h后,倒置显微镜下观察细胞形态,MTT比色法检测细胞增殖变化,曲线拟合法计算通莲汤和氟脲嘧啶50%抑制浓度(IC50);以两者48 h IC50浓度处理细胞48 h,流式细胞技术(FCM)测定细胞周期,Western blot法测定细胞IκB激酶β(IKKβ),NF-κB,phosph-NF-κB蛋白水平。 结果: 通莲汤和氟脲嘧啶48 h IC50值分别为192.74 mg·L-1,23.61 mg·L-1;与空白对照组相比,通莲汤显著影响MGC803细胞周期中G2期,氟脲嘧啶显著影响MGC803细胞周期中G1期(P<0.05);通莲汤和氟脲嘧啶均能显著抑制IKKβ与NF-κB的蛋白表达。 结论: 通莲汤抑制MGC803细胞生长与抑制细胞于G2期,下调NF-κB通路中IKKβ,NF-κB蛋白的表达有关。 相似文献
107.
目的 探讨上海市社区居民中心性肥胖与打鼾对血脂异常的交互作用。方法 利用2017年上海市慢性病及其危险因素监测数据(SHCR-2017),通过多阶段分层抽样,合计纳入研究对象20 259人,应用多因素logistic回归评价中心性肥胖与打鼾对血脂异常患病的影响。采用相乘交互、相加交互作用模型评估中心性肥胖和打鼾对血脂异常患病的交互作用。结果 上海市血脂异常检出率为35.5%,高甘油三酯血症(18.2%)和低高密度脂蛋白胆固醇血症(15.8%)为主要特征。经混杂因素调整后,中心性肥胖(OR=1.74,95%CI:1.63~1.85)与打鼾(OR=1.16,95%CI:1.09~1.24)均与血脂异常相关。交互作用分析表明,中心性肥胖与打鼾对血脂异常患病无显著相乘交互作用(OR=0.98,95%CI:0.87~1.11)。两者对血脂异常患病存在相加交互作用(RERI=2.21,95%CI:1.61~2.81;SI=3.40,95%CI:3.07~3.78;AP=0.54,95%CI:0.49~0.58)。血脂异常四种临床类型中,研究对象对高甘油三酯血症、低高密度脂蛋白胆固醇血症患病的相加交... 相似文献
108.
BACKGROUND AND PURPOSE
Conditioned gaping reactions reflect nausea-induced behaviour in rats. Cannabinoid 1 receptor (CB1) agonists interfere with the establishment of nausea-induced conditioned gaping; however, it is not known if their effects are mediated by an action at peripheral or central CB1 receptors.EXPERIMENTAL APPROACH
We utilized the conditioned gaping model of nausea to evaluate the effect of peripheral and central administration of the peripherally restricted CB1 agonist, CB13, on the establishment of LiCl-induced gaping in rats. We further evaluated the ability of HU-210 administered to the gustatory insular cortex (GIC) or visceral insular cortex (VIC) to interfere with LiCl-induced conditioned gaping and determined if this effect was mediated by CB1 receptors.KEY RESULTS
Central, but not peripheral, CB13 suppressed LiCl-induced conditioned gaping. Central administration of the potent CB1 agonist, HU-210, delivered to the VIC, but not the GIC, suppressed the establishment of LiCl-induced gaping reactions, but not LiCl-induced suppression of hedonic reactions or conditioned taste avoidance. This pattern of results suggests that HU-210 delivered to the VIC prevented LiCl-induced nausea, but not learning per se. The suppression of LiCl-induced conditioned gaping by HU-210 was mediated by CB1 receptors because it was prevented by co-administration of CB1 antagonist/inverse agonist, AM-251, into the VIC. A high dose of AM-251 (20 µg) administered alone into the VIC did not produce conditioned gaping reactions.CONCLUSIONS AND IMPLICATIONS
The nausea-relieving effects of CB1 agonists, but not the nausea-inducing effects of CB1 inverse agonists, are mediated, at least in part, by their action at the VIC in rats. 相似文献109.
目的了解广州市荔湾区青少年脊柱侧凸的患病率。方法 2011年7月~2012年1月对荔湾区8351名7~15岁在校中小学生进行了脊柱侧凸普查,应用脊柱侧凸两检法(体检、X线照片),体检阳性或可疑阳性者到医院照脊柱全长正侧位X片,采用Cobb法测量,Cobb角≥10°诊断为脊柱侧凸。结果一检阳性结果 175名(2.1%),二检阳性为85名(1.02%),男性31名,女性54名,男∶女患病率比为1∶1.76,其中特发性脊柱侧凸81名,占95.3%,先天性侧凸3名,神经肌肉源性1名。结论荔湾区中小学生脊柱侧凸发病率为1.02%,通过普查,可以早发现、早诊断青少年脊柱侧凸,及时选择适当方法进行治疗。 相似文献
110.
目的: 观察五子降糖方对2型糖尿病模型大鼠血糖及骨骼肌葡萄糖转运蛋白4(GLUT4)表达的影响,初步探讨其改善糖代谢的分子机制。 方法: 采用高脂饮食喂养6周联合ip小剂量链脲佐菌素(STZ)的方法建立2型糖尿病大鼠模型,随机分为模型组、二甲双胍(0.1 g·kg-1)组、五子降糖方低、中、高剂量组(3.5,7.0,14.0 g·kg-1),另设正常组,各组大鼠分别ig相应的药物,容量为7.5 mL·kg-1。模型组及正常组ig纯净水;二甲双胍组ig盐酸二甲双胍混悬液;五子降糖方低、中、高剂量组ig五子降糖方混悬液,干预6周。分别在ig前、ig后2周、4周、6周测空腹血糖及餐后2 h血糖。ig后6周处死大鼠,取其左后肢大腿股直肌组织,检测GLUT4蛋白的表达。 结果: 与正常组比较,模型组T2DM大鼠空腹和餐后2 h血糖升高,骨骼肌GLUT4蛋白表达水平降低,差异均具有统计学意义(P<0.05);五子降糖方能够降低T2DM大鼠空腹血糖及餐后2 h血糖水平,提高T2DM大鼠骨骼肌GLUT4蛋白表达水平,差异均具有统计学意义(P<0.05)。 结论: 五子降糖方可降低T2DM模型大鼠空腹及餐后2 h血糖,作用机制可能与提高骨骼肌GLUT4蛋白表达水平有关。 相似文献