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71.
Early life is a sensitive period, in which enhanced neural plasticity allows the developing brain to adapt to its environment. This plasticity can also be a risk factor in which maladaptive development can lead to long-lasting behavioral deficits. Here, we test how early-life exposure to the selective-serotonin-reuptake-inhibitor (SSRI), fluoxetine, affects motivation, and dopaminergic signaling in adulthood. We show for the first time that mice exposed to fluoxetine in the early postnatal period exhibit a reduction in effort-related motivation. These mice also show blunted responses to amphetamine and reduced dopaminergic activation in a sucrose reward task. Interestingly, we find that the reduction in motivation can be rescued in the adult by administering bupropion, a dopamine-norepinephrine reuptake inhibitor used as an antidepressant and a smoke cessation aid but not by fluoxetine. Taken together, our studies highlight the effects of early postnatal exposure of fluoxetine on motivation and demonstrate the involvement of the dopaminergic system in this process.SIGNIFICANCE STATEMENT The developmental period is characterized by enhanced plasticity. During this period, environmental factors have the potential to lead to enduring behavioral changes. Here, we show that exposure to the SSRI fluoxetine during a restricted period in early life leads to a reduction in adult motivation. We further show that this reduction is associated with decreased dopaminergic responsivity. Finally, we show that motivational deficits induced by early-life fluoxetine exposure can be rescued by adult administration of bupropion but not by fluoxetine.  相似文献   
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There is substantial evidence documenting the effects of behavioural interventions on weight loss (WL). However, behavioural approaches to initial WL are followed by some degree of longer-term weight regain, and large trials focusing on evidence-based approaches to weight loss maintenance (WLM) have generally only demonstrated small beneficial effects. The current state-of-the-art in behavioural interventions for WL and WLM raises questions of (i) how we define the relationship between WL and WLM, (ii) how energy balance (EB) systems respond to WL and influence behaviours that primarily drive weight regain, (iii) how intervention content, mode of delivery and intensity should be targeted to keep weight off, (iv) which mechanisms of action in complex interventions may prevent weight regain and (v) how to design studies and interventions to maximise effective longer-term weight management. In considering these issues a writing team within the NoHoW Consortium was convened to elaborate a position statement, and behaviour change and obesity experts were invited to discuss these positions and to refine them. At present the evidence suggests that developing the skills to self-manage EB behaviours leads to more effective WLM. However, the effects of behaviour change interventions for WL and WLM are still relatively modest and our understanding of the factors that disrupt and undermine self-management of eating and physical activity is limited. These factors include physiological resistance to weight loss, gradual compensatory changes in eating and physical activity and reactive processes related to stress, emotions, rewards and desires that meet psychological needs. Better matching of evidence-based intervention content to quantitatively tracked EB behaviours and the specific needs of individuals may improve outcomes. Improving objective longitudinal tracking of energy intake and energy expenditure over time would provide a quantitative framework in which to understand the dynamics of behaviour change, mechanisms of action of behaviour change interventions and user engagement with intervention components to potentially improve weight management intervention design and evaluation.  相似文献   
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The International Journal of Cardiovascular Imaging - There is conflicting evidence regarding the significance of iatrogenic atrial septal defects (iASDs) after transseptal puncture during...  相似文献   
74.
Postexercise blood pressure reduction in elderly hypertensive patients   总被引:2,自引:0,他引:2  
OBJECTIVES: We sought to study: 1) the impact of hemodynamic and left ventricular function on short-term postexercise blood pressure reduction in elderly hypertensive patients; and 2) the 22-h postexercise effects on ambulatory blood pressure in elderly hypertensive patients. BACKGROUND: Although early exercise provokes postexercise blood pressure reduction, the mechanisms underlying this response are not completely understood. Besides, it is unclear whether the reduction in blood pressure after exercise lasts long enough to have clinical relevance in elderly hypertensive patients. METHODS: We studied 24 elderly hypertensive patients (age 68.9 +/- 1.5 years) and 18 age-matched normotensive control subjects (age 68.1 +/- 1.2 years). Cardiac output (carbon dioxide rebreathing) and blood pressure (auscultatory) were measured at rest and after a 45-min period of low-intensity bicycle exercise (50% maximal oxygen uptake) and at 15, 30, 60 and 90 min after exercise. Left ventricular function (by Doppler echocardiography) was also evaluated. Ambulatory blood pressure monitoring was evaluated after 45 min of exercise or 45 min of rest, in a randomized order. RESULTS: In the hypertensive patients, exercise provoked a significant reduction in blood pressure, cardiac output, stroke volume and left ventricular end-diastolic volume. It also provoked a significant reduction in systolic, mean and diastolic blood pressure during a 22-h period, at daytime and nighttime. CONCLUSIONS: The short-term reduction in blood pressure after exercise in elderly hypertensive patients is associated with a decrease in stroke volume and left ventricular end-diastolic volume. The 22-h postexercise reduction in blood pressure demonstrates the clinical relevance of low-intensity exercise in elderly hypertensive patients.  相似文献   
75.
The growing use of dermal fillers, specifically the use of hyaluronic acid, can be explained by their effectiveness and versatility as well as their favorable safety profiles. Nevertheless, early and late complications with varying levels of severity may occur. The incidence of complications is low and the majority of adverse events are mild (edema, erythema, and local ecchymosis) and of limited duration. However, more severe events, such as ischemia and necrosis, may occur. The symptoms of ischemia can occur immediately after the injection or several hours after the procedure. Here, the authors report three cases of necrosis after hyaluronic acid injection with the first symptoms presenting only several hours after the procedure. The patients were treated immediately after the diagnosis. The aim of this review is to communicate the possibility of the delayed-type presentation of necrosis, present the signs and symptoms that lead to early diagnosis, and review the treatment possibilities of this severe complication.Dermal fillers have been injected with increasing frequency over the past three decades for soft-tissue augmentation by volume expansion in the management of the aging face. In 2012, there were about two million procedures using dermal fillers, according to the American Society of Plastic Surgeons, five percent more than in 2011 and 205 percent more than in 2000, second only to botulinum toxin type A. These minimally invasive and nonsurgical cosmetic procedures were the two most commonly performed in this range of time studied.1,2The growing use of dermal fillers, specifically the use of hyaluronic acid (HA), can be explained by their effectiveness and versatility as well as their favorable safety profiles. Nevertheless, early and late complications with varying levels of severity may occur. The incidence of complications is low and the majority of adverse events are mild (edema, erythema, and local ecchymosis) and of limited duration. However, more severe events, such as ischemia and necrosis, may occur.Injection necrosis is a rare, but important, complication associated with dermal fillers. Necrosis can be attributed to one of two factors—an interruption of vascular supply due to compression or frank obstruction of vessels by direct injection of the material into a vessel itself. The glabella is the injection site commonly believed to be at greater risk for necrosis, but it can also occur at the nasolabial fold.3 Risk factors for intravascular injection include site of application (deep injection of filler products at or near the site of named vessels), volume applied (larger amounts of product can cause a proportionally greater degree of arterial obstruction), and previous scarring (deep tissue scars may stabilize and fix arteries in place, making them easier to penetrate with small sharp needles).4The initial presentation of vascular events may include pain and discomfort disproportionate to what is typically experienced following filler treatments and clinical findings, including blanching, livedo pattern, or violaceous discoloration.4 Although many cases report this immediate post-injection presentation as the typical background seen in a necrosis event, there are few reports with the first symptom presenting only hours after augmentation. See Figures 1 through through3,3, where the authors present three cases of vascular compromise after soft-tissue augmentation with delayed-type presentation. Open in a separate windowOpen in a separate windowFigures 2Aand 2B.Case 2: Necrosis and secondary infection 48 hours after the HA injection (a). Discrete scars in the affected area after treatment (b). Open in a separate windowOpen in a separate windowFigures 1Aand 1B.Case 1: Edema, erythema, and progressive violaceous reticulated patch, livedoid area were observed on the left cheek 36 hours after the injection (a). Complete healing five days after hyaluronidase application and nine days after the HA injection (b). Open in a separate windowOpen in a separate windowFigures 3Aand 3B.Case 3: Necrosis and secondary infection 48 hours after the HA injection (a). Erythema, hipercromia, and discreet scars in the affected area after treatment (b).  相似文献   
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OBJECTIVE:

Transarterial chemoembolization is the treatment of choice for intermediate-stage hepatocellular carcinoma. However, there are no clear data supporting transarterial chemoembolization vs. transarterial embolization or regarding the best chemotherapeutic agent, which may suggest a preponderant role of ischemia over chemotherapeutic action. This study sought to evaluate the radiological response and outcome of transarterial chemoembolization modified by n-butyl cyanoacrylate addition compared to conventional transarterial chemoembolization in hepatocellular carcinoma patients.

MATERIALS AND METHODS:

A retrospective review identified forty-seven patients who underwent modified chemoembolization and thirty-three who underwent conventional chemoembolization between June 2006 and December 2011. The radiological response was reassessed using the modified Response Evaluation Criteria in Solid Tumors. The sustained complete response, time to progression and overall survival rates were also analyzed.

RESULTS:

Complete response rates were significantly higher in patients who had undergone modified chemoembolization compared to those who had undergone conventional treatment (61.7% and 24.3%, respectively; p<0.001). The rate of sustained complete response was significantly higher in the modified chemoembolization group compared to the conventional chemoembolization group (median of 236 and 37 days, respectively; p<0.001). Time to progression was significantly higher in the modified chemoembolization group compared to the conventional chemoembolization group (median of 424 and 201 days, respectively; p=0.042). Overall survival rates revealed no difference between patients who received modified chemoembolization and conventional chemoembolization (median of 483 and 399 days, respectively; p=0.316).

CONCLUSION:

Transarterial chemoembolization modified by n-butyl cyanoacrylate addition was superior to conventional transarterial chemoembolization in terms of the radiological response in the first imaging control. Although the sustained complete response and time to progression rates were higher for the modified chemoembolization group, no differences in overall survival rates were observed.  相似文献   
80.
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