Hyperemic response of the brachial artery during the second half of pregnancy

OBJECTIVE

To determine if women who developed preeclampsia had measurable differences in the vascular response postrelease of a 1-minute blood flow occlusion.

METHODS

A total of 33 nulliparous patients were enrolled in this study during the second half of the pregnancy. All had baseline Doppler flow velocities while resting in the left lateral decubitus. Subsequently, a blood pressure cuff was inflated for 60 seconds in the forearm so as to occlude blood flow. Doppler waveforms were analyzed immediately after the release of the blood pressure cuff and on a single beat occurring at 15 second intervals for a total of five readings. After a rest period, patients were asked to squeeze a handheld manometer at maximum strength as long as possible. Doppler waveforms were analyzed as above. The Doppler waveforms of all enrolled patients who subsequently developed preeclampsia any time after the study were compared to those who remained normotensive.

RESULTS

1) The "hyperemic response" that occurred immediately after release of the blood pressure occlusion of the forearm was significantly different between patients who subsequently developed preeclampsia compared with those who remained normotensive, 2) the hyperemic response that occurred after the isometric handgrip exercise was not significantly different between the two groups, and 3) sensitivity, specificity, and negative predictive values were high, but positive predictive values were low.

CONCLUSION

There was a significant difference in the hyperemic response of the brachial artery to a short period of ischemia of the forearm (blood pressure occlusion) between normotensive patients and a group of patients who subsequently developed preeclampsia.

The influence of drug class on reward in substance use disorders

In the United States, the societal costs associated with drug use surpass $500 billion annually. The rewarding and reinforcing properties that drive the use of these addictive substances are typically examined concerning the neurobiological effects responsible for their abuse potential. In this review, terms such as "abuse potential," "drug," and "addictive properties" are used due to their relevance to the methodological, theoretical, and conceptual framework for understanding the phenomenon of drug-taking behavior and the associated body of preclinical and clinical literature. The use of these terms is not intended to cast aspersions on individuals with substance use disorders (SUD). Understanding what motivates substance use has been a focus of SUD research for decades. Much of this corpus of work has focused on the shared effects of each drug class to increase dopaminergic transmission within the central reward pathways of the brain, or the "reward center." However, the precise influence of each drug class on dopamine signaling, and the extent thereof, differs considerably. Furthermore, the aforementioned substances have effects on several neurobiological targets that mediate and modulate their addictive properties. The current manuscript sought to review the influence of drug class on the rewarding effects of each of the major pharmacological classes of addictive drugs (i.e., psychostimulants, opioids, nicotine, alcohol, and cannabinoids). Our review suggests that even subtle differences in drug effects can result in significant variability in the subjective experience of the drug, altering rewarding and other reinforcing effects. Additionally, this review will argue that reward (i.e., the attractive and motivational property of a stimulus) alone is not sufficient to explain the abuse liability of these substances. Instead, abuse potential is best examined as a function of both positive and negative reinforcing drug effects (i.e., stimuli that the subject will work to attain and stimuli that the subject will work to end or avoid, respectively). Though reward is central to drug use, the factors that motivate and maintain drug taking are varied and complex, with much to be elucidated.

Impulsivity and Cognitive Functioning in Inpatients with Concurrent Disorders: A Comparative Study with Healthy Controls and Evaluation of Treatment-Related Changes: Impulsivité et fonctionnement cognitif chez les patients hospitalisés présentant des troubles concomitants : étude comparative avec des témoins sains et évaluation des changements liés au traitement

OBJECTIVE

This study investigated impulsivity and working memory among CD inpatients across treatment and compared to controls.

METHODS

Patients (N = 56, Mage = 38.2, SD = 11.7, 17F) and healthy controls (N = 50, Mage = 31.9, SD = 10.0, 25F) completed a battery of self-report questionnaires and behavioural tasks assessing working memory and impulsivity (response inhibition, delay discounting, reflection, decision-making). Patients were assessed within 2 weeks of admission (baseline) and at 6 months (follow-up). Controls completed a single session at baseline. Patient demographics, diagnostic status, and treatment outcome (discharge with or without medical advice) were retrieved from medical records.

RESULTS

Group differences in demographics were probed for inclusion as covariates. At baseline, patients had greater self-reported impulsivity on the UPPS-P (negative and positive urgency) and BIS (motor and non-planning), and greater delay discounting than controls. Among patients, there was no association between treatment adherence and working memory, self-report, or behavioural impulsivity, and no change in behavioural impulsivity was observed from baseline to follow-up.

CONCLUSIONS

This is the first study to assess impulsivity and working memory in the context of CD treatment. Patients exhibited greater impulsivity on choice-based and various self-report measures. The absence of treatment-related changes in impulsivity and working memory outcomes suggests that conventional treatments may be neglecting to target potentially key areas of functioning. Further research is needed to examine how treatment affects impulsivity and related functions in individuals with CD, and their impact on clinical outcomes.