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1.
痛情绪是指因疼痛引发的情绪和情感体验,是疾病过程中最常见的一种情绪。痛情绪相关神经机制非常复杂,但主要与单胺类神经递质、神经肽和某些神经环路有关,笔者将结合目前研究现状分别从以上两方面展开,就痛情绪相关单胺类神经递质和神经肽在受体分类、脑区通路、共疾病以及各神经递质之间的联系和痛情绪相关神经环路中各个蛋白的作用机制等方面进行探讨。  相似文献   
2.
《Neuropsychopharmacology》2019,85(11):936-945
BackgroundDisruptions in the decision-making processes that guide action selection are a core feature of many psychiatric disorders, including addiction. Decision making is influenced by the goal-directed and habitual systems that can be computationally characterized using model-based and model-free reinforcement learning algorithms, respectively. Recent evidence suggests an imbalance in the influence of these reinforcement learning systems on behavior in individuals with substance dependence, but it is unknown whether these disruptions are a manifestation of chronic drug use and/or are a preexisting risk factor for addiction.MethodsWe trained adult male rats on a multistage decision-making task to quantify model-free and model-based processes before and after self-administration of methamphetamine or saline.ResultsIndividual differences in model-free, but not model-based, learning prior to any drug use predicted subsequent methamphetamine self-administration; rats with lower model-free behavior took more methamphetamine than rats with higher model-free behavior. This relationship was selective to model-free updating following a rewarded, but not unrewarded, choice. Both model-free and model-based learning were reduced in rats following methamphetamine self-administration, which was due to a decrement in the ability of rats to use unrewarded outcomes appropriately. Moreover, the magnitude of drug-induced disruptions in model-free learning was not correlated with disruptions in model-based behavior, indicating that drug self-administration independently altered both reinforcement learning strategies.ConclusionsThese findings provide direct evidence that model-free and model-based learning mechanisms are involved in select aspects of addiction vulnerability and pathology, and they provide a unique behavioral platform for conducting systems-level analyses of decision making in preclinical models of mental illness.  相似文献   
3.
ObjectiveMany young adults are affected by attention deficit hyperactivity disorder (ADHD) and often desire non-pharmacological treatment options. Mind-body techniques might serve as complementary therapies to first-line stimulant medications, but studies are limited. Tai Chi is an increasingly popular practice that integrates movement with cognitive skills relevant to ADHD. We performed a feasibility trial of Tai Chi training in undergraduates to inform the design of a fully powered randomized controlled trial (RCT).MethodUndergraduates with ADHD were recruited, screened, enrolled, and assessed at baseline. They were assigned to three parallel seven-week intervention arms, Tai Chi, Active Control (cardio-aerobic fitness), and Inactive Control (no contact), with follow-up assessments. Feasibility of a larger clinical trial was evaluated, especially with respect to enrollment and retention. Additionally, potential clinical outcome measures were examined for practicality and reliability.Results21 participants were assessed at baseline and 19 at follow-up (90 % retention). The primary clinical outcome measure, self-reported inattention symptoms (Conners' CAARS-S:L DSM-IV Inattentive Symptoms subscale), exhibited good test-retest reliability in controls (r = 0.87, n = 10) and correlated with reduced mindfulness (FFMQ acting with awareness subscale) at baseline (r = -0.74, n = 20). Class attendance and self-reported daily practice time were variable. Randomization to group classes was hindered by the college students' restricted schedules.ConclusionThe high retention rate and good data quality suggest that an RCT of Tai Chi for ADHD is feasible. Further measures are identified to improve enrollment rates, adherence, and randomization procedures. Future work might extend to other young adult populations and high school students.  相似文献   
4.
5.
目的:观察多巴胺联合硝普钠治疗老年重症心力衰竭患者的临床疗效及对患者心功能、胱抑素(CysC)、同型半胱氨酸(Hcy)、血浆脑钠肽(BNP)水平的影响。方法:本院的108例老年重症心力衰竭患者被随机均分为硝普钠组(给予常规治疗及硝普钠治疗)与联合治疗组(在硝普钠组基础上联合应用多巴胺治疗);治疗7d后,对比两组临床疗效,观察两组治疗前后的心功能指标和血清CysC、Hcy、血浆BNP水平变化,及治疗期间的不良反应。结果:联合治疗组总有效率显著高于常规治疗组(94.44%比77.78%,P=0.012)。治疗后,与硝普钠组比较,联合治疗组左室射血分数(LVEF)[(42.86±9.23)%比(55.06±9.64)%]、每搏指数(SI)[(29.04±5.36)比(35.48±5.71)]显著提高,左室舒张末期内径(LVEDd)[(60.73±6.38)mm比(55.41±6.04)mm]、左室收缩末期内径(LVESd)[(42.91±4.36)mm比(37.18±4.18)mm]显著缩小,血清CysC[(1.42±0.24)mg/L比(1.07±0.18)mg/L]、Hcy[(19.38±3.38)μmol/L比(17.09±2.97)μmol/L],血浆BNP[(1968.74±159.76)pg/ml比(1105.96±118.53)pg/ml]水平显著降低(P均=0.001)。两组不良反应发生率无显著差异(P=0.781)。结论:多巴胺联合硝普钠治疗老年重症心衰患者的疗效显著优于硝普钠,可显著改善心功能,并可降低血清CysC、Hcy、血浆BNP水平,对预防病情恶化有积极意义。  相似文献   
6.
Abstract

Objectives: Overlapping decreases in extrastriatal dopamine D2/D3-receptor availability and glucose metabolism have been reported in subjects with schizophrenia. It remains unknown whether these findings are physiologically related or coincidental.

Methods: To ascertain this, we used two consecutive 18F-fluorodeoxyglucose and 18F-fallypride positron emission tomography scans in 19 healthy and 25 unmedicated schizophrenia subjects. Matrices of correlations between 18F-fluorodeoxyglucose uptake and 18F-fallypride binding in voxels at the same xyz location and AFNI-generated regions of interest were evaluated in both diagnostic groups.

Results: 18F-fluorodeoxyglucose uptake and 18F-fallypride binding potential were predominantly positively correlated across the striatal and extrastriatal grey matter in both healthy and schizophrenia subjects. In comparison to healthy subjects, significantly weaker correlations in subjects with schizophrenia were confirmed in the right cingulate gyrus and thalamus, including the mediodorsal, lateral dorsal, anterior, and midline nuclei. Schizophrenia subjects showed decreased D2/D3-receptor availability in the hypothalamus, mamillary bodies, thalamus and several thalamic nuclei, and increased glucose uptake in three lobules of the cerebellar vermis.

Conclusions: Dopaminergic system may be involved in modulation of grey matter metabolism and neurometabolic coupling in both healthy human brain and psychopathology. Hyperdopaminergic state in untreated schizophrenia may at least partly account for the corresponding decreases in grey matter metabolism.  相似文献   
7.
BackgroundThe feeling of body ownership relies on the binding of multisensory body-related signals. Various sensory abnormalities have been described in Parkinson's disease (PD).ObjectiveTo assess the rubber hand illusion (RHI) in patients with PD (PwPD) and age-matched healthy controls (CTRL). To evaluate the influence of the dopaminergic system in a PwPD subgroup OFF medication.MethodsThe RHI paradigm was applied to 42 PwPD and 48 CTRL. In this experimental setup, stroking a visible plastic hand simultaneously with the covered real hand elicits the feeling of ownership over the seen hand. Asynchronous stroking served as a control condition. Proprioceptive bias and an illusion score based on a questionnaire were used as measures of the RHI. Seventeen PwPD additionally underwent the experiments “OFF medication”.ResultsCompared to CTRL, PwPD showed higher proprioceptive bias independent of the stroking condition (p = 0.015), and had higher illusion scores in the asynchronous condition (p < 0.05). In PwPD, there were no significant differences between ON- and OFF-medication state.ConclusionIn PwPD, responses to the RHI are less specific with respect to the degree of synchronicity of brushstrokes. This might be attributed to a less stable body representation, internal “noise” during multisensory integration, or a blur of temporal discrimination in PD. The fact that RHI measures did not differ between ON- and OFF-medication states indicates an involvement of non-dopaminergic transmitter systems in this finding.  相似文献   
8.
Objective: To evaluate the effect of dopamine on thyroid hormone tests and prolactin (PRL) and to assess requirement for L-thyroxin (LT4).

Methods: The infants (n?=?102) were divided into three groups (Group 1; received no dopamine, Group 2 received ≤25?mg/kg cumulative dose and Group 3; received >25?mg/kg cumulative dose). Blood samples were taken at 6–8 days (timepoint 1), 13–15 days (timepoint 2), and 4–6 weeks of life (timepoint 3).

Results: Respiratory distress syndrome was higher in group 2 and 3. Patnet ductus arteriosus was higher in group 3 than in groups 1 and 2. Duration and cumulative dose in group 3 were higher than group 2. There was no difference between thyroid hormones that were taken after stopping infusion at timepoint 3 among all groups. No therapy with LT4 was needed. PRL levels were higher at timepoint 1 in group 1 than compared to group 2 and 3 (p?p?>?0.05). This difference was disappeared at following timepoints.

Conclusions: The release of TSH, FT3, FT4 and PRL were not inhibited and prophylactic thyroid hormone treatment was not required in VLBW infants receiving dopamine infusions.  相似文献   
9.
Sunitinib (SUN) is a multi-targeted receptor tyrosine kinase inhibitor (TKI) that may lead to drug resistance and metastasis because of increased cancer stem-like cells (CSCs) due to the induction of hypoxia. Our group has proved that dopamine (DA) can specifically reduce CSC frequency and enhance the response of SUN in drug-resistant breast cancerand non-small cell lung cancer (NSCLC). In this study, DA and SUN combination therapy was investigated in the treatment of pancreatic cancer, a malignant tumor with high mortality rate and very limited therapies. The cytotoxicity assay, clone formation assay and wound healing assay in two pancreatic cancer cell line PANC-1 and SW1990 showed that DA could significantly increase the effect of SUN on cell survival, clone formation ability and migration ability. Besides, SW1990 cell-derived xenograft model and a pancreatic cancer patient-derived xenograft (PDX) model were constructed, further proving that DA could increase the in vivo anti-tumor efficacy of SUN, and could be reversed by SCH23390, a D1 dopamine receptor (D1DR) antagonist. Moreover, the CSC frequency of the combination groups was lower than the control groups or SUN monotherapy groups. In addition, the body weight, H&E staining and blood routine test results showed that the combination therapy was safe. In summary, DA and SUN combination therapy could be a promising strategy for the treatment of pancreatic cancer.  相似文献   
10.
ObjectivesHyperechogenicity of the substantia nigra (SN) and abnormal dopamine transporter-single-photon emission computed tomography (DAT-SPECT) are biomarkers commonly used in the assessment of prodromal synucleinopathy. Our goals were as follows: (1) to compare echogenicity of SN in idiopathic rapid eye movement (REM) behavior disorder (iRBD), Parkinson's disease (PD) without RBD (PD-noRBD), PD with RBD (PD + RBD), and control subjects; and (2) to examine association between SN degeneration assessed by DAT-SPECT and SN echogenicity.Patients/methodsA total of 61 subjects with confirmed iRBD were examined using Movement Disorders Society-unified PD rating scale (MDS-UPDRS), TCS (transcranial sonography) and DAT-SPECT. The results were compared with 44 patients with PD (25% PD + RBD) and with 120 age-matched healthy subjects.Results and conclusionThe abnormal SN area was found in 75.5% PD, 23% iRBD and 7.3% controls. Median SN echogenicity area in PD (0.27 ± 0.22 cm2) was higher compared to iRBD (0.07 ± 0.07 cm2; p < 0.0001) and controls (0.05 ± 0.03 cm2; p < 0.0001). SN echogenicity in PD + RBD was not significantly different from PD-noRBD (0.30 vs. 0.22, p = 0.15).Abnormal DAT-SPECT was found in 16 iRBD (25.4%) and 44 PD subjects (100%). No correlation between the larger SN area and corresponding putaminal binding index was found in iRBD (r = −0.13, p = 0.29), nor in PD (r = −0.19, p = 0.22).The results of our study showed that: (1) SN echogenicity area in iRBD was higher compared to controls, but the hyperechogenicity was present only in a minority of iRBD patients; (2) SN echogenicity and DAT-SPECT binding index did not correlate in either group; and (3) SN echogenicity does not differ between PD with/without RBD.  相似文献   
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