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51.

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   
52.
The neurotransmitters serotonin and dopamine both have a critical role in the underlying neurobiology of different behaviors. With focus on the interplay between dopamine and serotonin, it has been proposed that dopamine biases behavior towards habitual responding, and with serotonin offsetting this phenomenon and directing the balance toward more flexible, goal-directed responding. The present focus paper stands in close relationship to the publication by Worbe et al. (2015), which deals with the effects of acute tryptophan depletion, a neurodietary physiological method to decrease central nervous serotonin synthesis in humans for a short period of time, on the balance between hypothetical goal-directed and habitual systems. In that research, acute tryptophan depletion challenge administration and a following short-term reduction in central nervous serotonin synthesis were associated with a shift of behavioral performance towards habitual responding, providing further evidence that central nervous serotonin function modulates the balance between goal-directed and stimulus-response habitual systems of behavioral control. In the present focus paper, we discuss the findings by Worbe and colleagues in light of animal experiments as well as clinical implications and discuss potential future avenues for related research.  相似文献   
53.
Introduction: Hepatocellular carcinoma (HCC) is one of the most common and lethal cancers. Progress has been made in treatment of HCC; however, improved outcomes are much needed. The increased metabolic needs of cancer cells underscore the importance of metabolic pathways in cancer cell survival. Lipid metabolism has a role in HCC development; aberrant overexpression of several key enzymes is seen in many solid human tumors.

Areas covered: We discuss aberrant lipid metabolism and the promise of multiple targets, in particular related to HCC treatment. We searched PubMed and clinicaltrials.gov for published and unpublished studies from 2000 to 2019. These terms were used: lipids, fatty acid metabolism, lipid metabolism, liver cancer, HCC, de novo fatty acid synthesis, ATP citrate lyase, stearoyl CoA denaturase, fatty acid synthase, acetyl coenzyme A carboxylase, CD147, KLF4, monoglyceride lipase, AMP activated protein kinase.

Expert opinion: The importance of dysregulation of fatty acid synthesis in cancer is a growing area of research. HCC demonstrates significant alteration in lipid metabolism, representing great potential as a target for novel therapeutics. Various agents have demonstrated promising anti-neoplastic activity. This strategy deserves further development for improved outcomes.  相似文献   

54.
One hundred fifty-one consecutive patients scheduled for double-contrast barium enema studies were assigned randomly to insufflation with either air or carbon dioxide (CO2) in a double-blind, prospective trial. Within 24 hours after the enema study, the patients were contacted by telephone by an interviewer, who completed a standard questionnaire. Radiographs from the enema studies were assessed for quality by two radiologists. Pain experienced after the procedure was graded from 0 (none) to 4 (severe). Clinically relevant (grades 2-4) pain was experienced by 30% of patients after insufflation with room air, compared with 11% of patients in whom CO2 was used for insufflation (P = .005). The mean pain score for CO2 was 0.4, and for room air, 1.2 (P less than .005). Although five patients experienced grade 4 pain after insufflation with air, no patient reported severe pain after CO2 insufflation. Post-evacuation films confirmed there was significantly less residual gas in the CO2 group. The quality of radiographs was equal in the two groups. CO2 has advantages for use in the double-contrast barium enema examination.  相似文献   
55.
56.
目的:植入材料、靶血管病变特征、术前状态、炎症因子及急性期蛋白均对急性冠状动脉综合征接受支架材料介入治疗后的效果有影响,为验证紫杉醇涂层支架临床应用后材料及宿主的相关反应,实验观察了接受紫杉醇涂层支架介入治疗的急性冠状动脉综合征患者的外周血热休克蛋白70水平变化,并分析其临床意义。方法:①连续性入选2004-12/2006-03在江苏大学附属人民医院行经皮冠状动脉介入治疗的78例急性冠状动脉综合征患者,全部病例均置入紫杉醇药物涂层支架。采用流式细胞仪测定症状发作平均(34.1±16.2)h的外周血单核细胞热休克蛋白70阳性表达水平。②所有患者随访至术后6个月,出现心源性死亡、再次心肌梗死、再发心绞痛、再次血运重建术和继发心衰等主要心脏不良事件者为近期预后不良组,无上述情况者判定为近期预后良好组,用logistic多元回归法分析术前状态、靶血管病变特征、植入支架的各项参数及外周血热休克蛋白70水平与主要心脏不良事件发生率的关系,并以同期健康体检者20例为正常对照组。结果:68例患者完成随访进入结果分析。①外周血热休克蛋白70水平:急性心肌梗死患者和不稳定型心绞痛患者比较差异无统计学意义(P>0.05),但均显著高于正常对照组(P<0.05)。②在多变量的logistic回归分析中,外周血热休克蛋白70独立于其危险因素,能预测急性冠状动脉综合征患者经皮冠状动脉介入治疗后近期主要心脏不良事件发生率(OR值为0.904,P<0.05)。结论:回归分析结果提示,应用紫杉醇涂层支架临床治疗近期效果评估中,外周血热休克蛋白70水平高的急性冠状动脉综合征患者近期心脏事件发生率较高,说明外周血热休克蛋白70可能成为判断紫杉醇涂层支架介入治疗后不良事件发生率的独立因素之一。  相似文献   
57.
目的:骨唾液酸蛋白在骨矿化形成方面扮演重要角色,实验观察其是否能诱导体外培养的人骨髓间充质干细胞向成骨细胞分化。方法:实验于2005—10/2006—12在解放军广州军区广州总医院医学实验科完成。①材料来源:选取在本院体检的健康志愿者2人,对本实验均知情同意。采用Ni-NTA亲和纯化技术,从本室构建的毕赤酵母GS115/pPICZaA-hbsp发酵上清中纯化重组人骨唾液酸蛋白。②实验方法:对健康志愿者进行髂骨穿刺抽取骨髓液,采用贴壁法培养得到骨髓间充质干细胞。设立4组:骨唾液酸蛋白组添加0.1nmol/L骨唾液酸蛋白;成骨诱导液组添加10nmol/L地塞米松、10mmol/L磷酸甘油、50mg/L抗坏血酸;联合组添加上述两组的所有试剂;空白对照组不添加任何处理因素;各组均处理细胞12d。⑧实验评估:光镜及电镜观察培养的细胞形态;以细胞计数法测定生长曲线,应用流式细胞仪分析细胞周期,采用免疫荧光细胞化学法和流式细胞分析检测干细胞标志物STRO-1的表达;生化试剂盒测定碱性磷酸酶活性;von Kossa染色法检测钙沉积。结果:①单个骨髓间充质干细胞为长梭形,经骨唾液酸蛋白处理后细胞大而扁平,原来密集的克隆分散开。②与空白对照组比较,骨唾液酸蛋白组引起细胞生长曲线右移,细胞Go/G,期比例平均增加12.09%(P〈0.01),S期比例减少65.92%(P〈0.01),STRO-1阳性细胞百分率下降26.54%(P〈0.01)。⑧与空白对照组比较,骨唾液酸蛋白组细胞碱性磷酸酶活性增加50.0%,成骨诱导液组增加59.5%,联合组增加71.43%,并且随着处理时间的延长,活性增加越显著。④空白对照组细胞vonKossa染色呈阴性,其余各组均呈阳性。其中联合组的黑色矿化结节体积最大、数目最多;骨唾液酸蛋白组的结节体积较小、数目较少;成骨诱导液组居中。结论:骨唾液酸蛋白对人骨髓间充质干细胞有促进成骨分化和矿化作用,且与成骨诱导液联用效果更佳。  相似文献   
58.
目的:为保护濒死心肌提供机会窗口,对比观察经冠脉移植自体骨髓单个核细胞或间充质干细胞后,实验性急性心肌梗死动物心功能变化及心肌组织核转录因子кB、心肌细胞凋亡情况。方法:实验于2005-03/2006-11在河北省人民医院实验中心完成。选用24只雄性冀中白猪,随机数字表法分为4组:正常对照组、模型组、单个核细胞组、间充质干细胞组,6只/组。①24只猪均以盐酸氯胺酮200mg臀部肌肉注射麻醉后,分别于各自右侧股骨抽取骨髓20mL,采用Fercoll法分离获得骨髓单个核细胞,加入胶体金溶液,培养12~16h待用。分离过程中取出含有骨髓单个核细胞成分的细胞层,常规培养传代,每3d换液1次,贴壁生长细胞即为骨髓间充质干细胞,加入胶体金溶液,培养24h待用。②除正常对照组外,其余各组均经导管球囊封闭第一对角支以远的前降支,复制猪急性心肌梗死模型。单个核细胞组、间充质干细胞组均于造模后立即开通前降支,分别经球囊注入预先分离的骨髓单个核细胞6×108个、间充质干细胞6×108个。模型组造模后于梗死1h开通前降支,经球囊注入磷酸盐缓冲液10mL。③各组分别于术前及术后4周经心脏超声检测心功能,取材行病理学检查、心肌组织核转录因子кB的免疫组织化学检测及心肌细胞凋亡检测。结果:24只雄性白猪均进入结果分析。①心功能变化:术前各组左心室收缩末内径、左心室舒张末内径、左心室射血分数、短轴缩短率基本相似。移植术后4周,正常对照组、单个核细胞组、间充质干细胞组左心室舒张末内径均明显低于模型组(F=4.68,P=0.01),左心室射血分数及短轴缩短率均明显高于模型组(F=5.14,P=0.01;F=3.32,P=0.04),各组左心室收缩末内径差异无显著性意义(F=1.64,P=0.21)。②心肌组织病理学改变:电镜下单个核细胞组、间充质干细胞组在梗死边缘区可见有胶体金颗粒的不成熟的心肌细胞,胞质中散在肌丝结构,肌丝排列紊乱不规则。③心肌组织核转录因子кB阳性率表达:与模型组比较,单个核细胞组、间充质干细胞组的梗死边缘区核转录因子кB阳性率明显降低(F=25.59,P=0.0001);正常心肌区核转录因子кB阳性率亦明显降低(F=18.20,P=0.0001)。④心肌细胞凋亡检测结果:与模型组比较,单个核细胞组、间充质干细胞组在心肌梗死区细胞凋亡率均明显降低(F=6.63,P=0.0027),梗死边缘区细胞凋亡率亦明显降低(F=36.07,P=0.0001)。正常心肌区单个核细胞组细胞凋亡率与模型组基本相似(F=9.69,P=0.004),但间充质干细胞组有所降低。⑤心功能与心肌细胞凋亡及心肌组织NF-кB的相关性:急性心肌梗死4周时,左心室射血分数与心肌细胞凋亡、心肌组织核转录因子кB均呈负相关(r=0.613,P=0.001;r=-0.437,P=0.033)。心肌细胞凋亡与心肌组织核转录因子кB呈正相关(r=0.672,P=0.002)。结论:经冠脉移植骨髓单个核细胞和间充质干细胞均可改善实验性急性心肌梗死动物的心功能,与梗死边缘区核转录因子кB表达降低及心肌细胞凋亡减少有关。骨髓单个核细胞移植的促血管增生作用优于间充质干细胞移植。  相似文献   
59.
目的:为健美运动员补充蛋白质提供科学的饮食方法,以期增加其肌肉体积,达到发展肌肉力量的同时健美体形,对健美运动员补充蛋白质研究作一综述。资料来源:应用计算机检索http://www.chkd.cnki.net/index.htm/,http://www.highwire.org/1994/2007有关补充蛋白质和增加肌肉力量相关的论文,英文检索词为"protein,strength",并限定语种为English;中文检索词为"补充蛋白质,肌肉力量",并限定语种为中文;另外手工查找与补充蛋白质和增加肌肉力量有关的资料和书籍。资料选择:对资料进行初审,选取与补充蛋白质和增加肌肉力量相关的文献,所选择的文献为研究原著,排除重复研究。资料提炼:共收集到200篇补充蛋白质和增加肌肉力量的文献,在选择、分析的基础上,排除重复或类似研究,最终提炼出29篇文献进行分类整理用于综述。资料综合:①运动与蛋白质关系非常密切。当运动强度加大时,使运动员尿氮排出增加并出现尿负氮平衡,因此要适当的补充蛋白质。②补充蛋白质,可以增加肌肉生理横断面,肌纤维增粗,增加肌红蛋白、血红蛋白、酶和蛋白类激素的合成,有利于增加肌肉力量。结论:健美运动员高强度训练期间,为了恢复运动中的消耗、修复损伤的组织、提高健美训练效果,应给予高蛋白类膳食。同时,还需要保持均衡膳食,适当增加矿物质和维他命以及其他营养补剂的补充。  相似文献   
60.
Although parental volubility, or amount of talk, has received considerable recent attention, infant volubility has received comparatively little attention despite its potential significance for communicative risk status and later linguistic and cognitive outcomes. Volubility of 16 typically developing infants from 2 to 11 months of age was longitudinally investigated in the present study across three social circumstances: parent talking to infant, parent not talking to infant and parent talking to interviewer while the infant was in the room. Results indicated that volubility was least in the Interview circumstance. There were no significant differences in volubility between the parent Talk and No Talk circumstances. Volubility was found to reduce with age. These results suggest that infants vocalise in a variety of circumstances, even when no one talks to or interacts with them. The presence of a stranger or perhaps overhearing adults speaking to each other, however, may significantly reduce infant volubility.  相似文献   
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