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1.
利用判别分析方法通过对测量的12个阿尔茨海默氏症(Alzheimer’s disease,AD)患者和12个健康者的尿液样本中儿茶酚胺(Catecholamines,CA)含量的测定及浓度作为训练集建立判别函数,进行疾病的诊断,交叉验证错误率为4.2%。采用随机余下的4个数据带入判别函数,进行预测,结果表明具有很好的预测能力,正确率达到了100%。此方法可以通过测量人体尿液中CA含量测定及浓度来诊断AD,对AD的尽早检测和早期治疗非常重要。2组线性判别函数分别为-19.91024+0.21873*E+0.23742*NE+0.11155*DOA+0.41789*L-DOPA-0.12661*DOPAC;-2.24864+0.03070*E+0.04914*NE+0 06892*DOA+0.01704*L-DOPA+0.01598*DOPAC。  相似文献   
2.
The authors used the acute phenylalanine-tyrosine depletion (APTD) method to test the effect of transient catecholamine precursor depletion on cocaine craving, euphoria, and self-administration. Eight nondependent, nontreatment-seeking cocaine users self-administered 3 doses of cocaine (0.6, 1.5, 3.0 mg/kg, taken intranasally) following ingestion of (a) a nutritionally balanced amino acid mixture, (b) APTD, and (c) APTD followed by L-dopa/carbidopa (2 × 100 mg/25 mg). APTD decreased both cue and cocaine-induced drug craving but not euphoria or self-administration. APTD + L-dopa also decreased drug craving, possibly reflecting the ability of L-dopa to transiently decrease dopamine cell firing. Together, these preliminary results suggest that the craving elicited by cocaine and cocaine cues is related to changes in catecholamine neurotransmission. Euphoria and the self-administration of freely available drugs by regular users, in comparison, might be better accounted for by other mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
《Planning》2019,(6)
嗜铬细胞瘤/副神经节瘤(pheochromocytoma and paranganglioma,PPGL)患者由于过度分泌儿茶酚胺,因而有较高的继发性高血压发生率和死亡率。大约1/4的PPGL具有侵袭转移性,这类不能切除的转移性病灶的治疗方案包括131I-间碘苄胍核素治疗、放疗和化疗,但此类治疗也只能控制肿瘤生长和抑制激素水平。过去10年,PPGL的临床和分子机制研究均取得了诸多进展,然而预后判断和治疗仍然是临床实践中最大的挑战。转移性PPGL患者的自然病史往往未知,其预后也不尽相同,目前诊断依然依赖于转移灶的存在,因此通常诊断时已是晚期。有研究对患者的临床和分子特征、导致转移性PPGL的特定信号通路的改变进行了探索,以期随着核素治疗、放疗联合分子靶向治疗的发展,提高该病的临床预后。  相似文献   
4.
目的: 观察川芎嗪对儿茶酚胺诱导大鼠心肌损伤时心肌细胞Bcl-2 和Fas 蛋白表达的影响。方法: 采用皮下多点注射异丙肾上腺素(ISO,5 mg·kg-1) 每天1 次, 连续3 d, 诱导大鼠心肌损伤,采用免疫组化方法检测Bcl-2 和Fas 蛋白的水平, 并利用图像分析系统分析蛋白阳性表达区域平均光密度值。结果: 损伤组和川芎嗪保护组心肌细胞Bcl-2蛋白表达较对照组均显著升高(P<0.01), 损伤组Fas 蛋白水平较对照组也显著升高(P<0.01), 川芎嗪保护组的Fas 蛋白水平较损伤组显著下降(P<0.01), 且Bcl-2 Fas 比值也较损伤组和对照组明显增加。川芎嗪保护组的病理损伤程度明显低于损伤组。结论: 川芎嗪可抑制儿茶酚胺诱导的心肌损伤时心肌细胞中促凋亡基因Fas 的表达, 提高心肌细胞中Bcl-2 Fas 比值。  相似文献   
5.
通过氨基甲基化的方法用碳-11甲基标记了N-甲基苯乙胺、N-甲基间羟基苯乙胺和N-甲基酪胺三种化合物,评价了放射性核素标记的三种化合物在昆明小鼠体内的生物分布特征。合成结果显示,[11 C]-N-甲基苯乙胺合成包括HPLC分离总耗时约30min,放化产率为25%、放化纯度98%,[11 C]-N-甲基间羟基苯乙胺合成包括HPLC分离总耗时约25min,放化产率为13%、放化纯度97%,[11 C]-N-甲基酪胺合成包括HPLC分离总耗时约25min,放化产率为28%、放化纯度98%;小鼠体内生物分布结果显示:三个标记物在各测定时间点小鼠靶器官心肌的摄取均比肺、肝、脾、肾等非靶器官的摄取低,心肌摄取与肌肉摄取相近。注射后10min时[11 C]-N-甲基苯乙胺的心与肺放射性摄取比为1/2.08、心与肝为1/2.94,[11 C]-N-甲基间羟基苯乙胺的心与肺放射性摄取比为1/2.56、心与肝为1/2.76,[11 C]-N-甲基酪胺的心与肺放射性摄取比为1/1.85、心与肝为1/5。以上结果提示,碳-11甲基标记N-甲基苯乙胺、N-甲基间羟基苯乙胺和N-甲基酪胺的合成方法虽然简单,但是心肌靶向性差,不适用于核素心肌显像。  相似文献   
6.
Propionic acid is a cell nutrient but also a stimulus for cellular signaling. Free fatty acid receptor (FFAR)-3, also known as GPR41, is a Gi/o protein-coupled receptor (GPCR) that mediates some of the propionate’s actions in cells, such as inflammation, fibrosis, and increased firing/norepinephrine release from peripheral sympathetic neurons. The regulator of G-protein Signaling (RGS)-4 inactivates (terminates) both Gi/o- and Gq-protein signaling and, in the heart, protects against atrial fibrillation via calcium signaling attenuation. RGS4 activity is stimulated by β-adrenergic receptors (ARs) via protein kinase A (PKA)-dependent phosphorylation. Herein, we examined whether RGS4 modulates cardiac FFAR3 signaling/function. We report that RGS4 is essential for dampening of FFAR3 signaling in H9c2 cardiomyocytes, since siRNA-mediated RGS4 depletion significantly enhanced propionate-dependent cAMP lowering, Gi/o activation, p38 MAPK activation, pro-inflammatory interleukin (IL)-1β and IL-6 production, and pro-fibrotic transforming growth factor (TGF)-β synthesis. Additionally, catecholamine pretreatment blocked propionic acid/FFAR3 signaling via PKA-dependent activation of RGS4 in H9c2 cardiomyocytes. Finally, RGS4 opposes FFAR3-dependent norepinephrine release from sympathetic-like neurons (differentiated Neuro-2a cells) co-cultured with H9c2 cardiomyocytes, thereby preserving the functional βAR number of the cardiomyocytes. In conclusion, RGS4 appears essential for propionate/FFAR3 signaling attenuation in both cardiomyocytes and sympathetic neurons, leading to cardioprotection against inflammation/adverse remodeling and to sympatholysis, respectively.  相似文献   
7.
Phenylpropanolamine (PPA) is an appetite suppressant. Repeated treatment with PPA can decrease food intake on initial days, but on subsequent days, food intake gradually returns to normal (tolerant effect). In an attempt to investigate the underlying mechanisms of PPA tolerance, the authors examined the roles of catecholamine (CAT) and hypothalamic neuropeptide Y (NPY) genome. Results revealed that pretreatment with either bupropion, a CAT transporter inhibitor, or α-methylparatyrosine, a tyrosine hydroxylase inhibitor, modulated the effect of PPA tolerance. Moreover, results also revealed that the alteration in NPY messenger RNA level coincided with the change of feeding behavior during PPA treatment and that infusions of NPY antisense oligonucleotide into the cerebroventicle abolished the effect of PPA tolerance. These findings suggest that cerebral CAT and hypothalamic NPY genome are involved in the development of tolerance to PPA-induced appetite suppression. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
Using a chronically placed jugular catheter and a silver electrode, it was possible to monitor short-term changes in the plasma concentration of cortisol and catecholamine in the marsupial sugar glider (Petaurus breviceps) and to monitor both heart and respiration rates. Males judged to be low in the social hierarchy of a particular group were exposed to the whole-body odor of a dominant male from the same social group, a foreign dominant male, or a castrate male. While there was no evidence of a change in any of the physiological parameters when a male was exposed to either a castrate male or a female, a rapid increase occurred in heart rate and plasma concentrations of cortisol, glucose and catecholamine when the donor was a dominant male from the same or a different social group.  相似文献   
9.
This study examined whether catecholamine-mediated signals in the anterior cingulate cortex (ACC) contribute to effort-based decision making. Rats were tested after 6-hydroxydopamine or vehicle infusions into the ACC in a T maze cost-benefit task in which the rats could choose either to climb a barrier to obtain a high reward in one arm or run into the other arm without a barrier to obtain a low reward. Results demonstrate that infusions of 6-hydroxydopamine induced a near total loss of tyrosine hydroxylase-positive fibers in the ACC. Unlike sham-lesioned rats, 6-hydroxydopamine-lesioned rats exhibited a reduced preference for the high-cost-high-reward response option when given the choice of obtaining a low reward with little effort. Thus, catecholamine-mediated signals in the ACC could play a role in effort-based decision making. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
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