Examining the Structure of Distress Tolerance: Are Behavioral and Self-Report Indicators Assessing the Same Construct?

Distress tolerance, or the ability to tolerate physically and emotionally aversive experiences, is a target of psychological intervention in contextual behavioral science. It has been conceptualized as a self-reported ability, as well as a behavioral tendency, and operationalized with a wide variability of questionnaires and behavioral tasks. The current study aimed to investigate whether behavioral tasks and self-report assessments of distress tolerance measure the same underlying dimension, two correlated dimensions, or whether method factors accounted for covariation above and beyond a general content dimension. A university student sample (N = 288) completed behavioral tasks associated with distress tolerance and self-report distress tolerance measures. Confirmatory factor analysis indicated that behavioral and self-report assessments of distress tolerance do not comprise a single dimension of distress tolerance, or two correlated dimensions of self-report or behavioral distress tolerance. Results also failed to support a bifactor conceptualization with a general distress tolerance dimension and domain-specific method dimensions for behavioral and self-report assessments. Findings suggest that more precision and attention to contextual factors are required in the operationalization and conceptualization of distress tolerance.

Feasibility of Computerized Cognitive-Behavioral Therapy Combined With Bifrontal Transcranial Direct Current Stimulation for Treatment of Major Depression.

BACKGROUND: Cognitive behavioral therapy (CBT) is effective in the treatment of major depressive disorder (MDD). Transcranial Direct Current Stimulation (tDCS) has demonstrated preliminary antidepressant effects and beneficial effects on cognitive function. OBJECTIVE: We investigated the feasibility and acceptability of using tDCS to enhance the effects of computer-based CBT for treatment of MDD. MATERIALS AND METHODS: In a randomized, double-blind, sham-controlled study, 14 patients with MDD on stable or no pharmacotherapy received active or sham bifrontal tDCS for four weeks with concurrent CBT. RESULTS: Ten participants completed the protocol. Three withdrew from the study because of lack of efficacy or dislike of the eCBT program. One was discontinued from the protocol by the investigators. Treatment was well tolerated, and most side-effects were mild and consistent with prior tDCS research. Pooled data from both groups showed significant baseline to endpoint improvement in depression (p = 0.008). Overall percent change on the HAMD-21 was 28.98%. The study was underpowered to detect differences in tDCS treatment groups. CONCLUSIONS: Combining tDCS with computer-based CBT is feasible for MDD. Further work is needed to evaluate potential synergistic effects of combined tDCS and CBT.

Agreement between blood draw techniques for assessing platelet activation by flow cytometry.

It is widely believed that assays of platelet activation are susceptible to preanalytical variables related to blood draw technique. We assessed platelet activation by whole blood flow cytometry and investigated the effects of: (1) drawing blood into vacuum tubes or manually aspirated syringes, and (2) discarding the first drawn blood sample (discard tube). Platelet P-selectin expression and platelet-monocyte complexes were measured by flow cytometry under both basal conditions and following stimulation with 0.1, 1, or 10 µM ADP. Bland-Altman plots demonstrated agreement between results for vacuum tube and syringe-aspirated samples with an a priori-defined clinically relevant agreement limit of 5%. Agreement of results was also observed between discard tube and second draw samples for both vacuum-driven and manually aspirated blood. We conclude that a vacuum tube or a manually-aspirated syringe can be used when assessing platelet activation by flow cytometry and that there is no need for a discard tube.

5 Hz Repetitive transcranial magnetic stimulation for posttraumatic stress disorder comorbid with major depressive disorder.

BACKGROUND: Standard clinical protocols for repetitive transcranial magnetic stimulation (rTMS) for major depressive disorder (MDD) apply 10 Hz pulses over left prefrontal cortex, yet little is known about the effects of rTMS in more diagnostically complex depressed patients. OBJECTIVE/HYPOTHESIS: Posttraumatic stress disorder (PTSD) is commonly comorbid with MDD, and while rTMS has been shown to alleviate PTSD symptoms in preliminary studies, ideal parameters remain unclear. We conducted a prospective, open-label study of 5 Hz rTMS for patients with comorbid PTSD + MDD and hypothesized stimulation would reduce symptoms of both disorders. METHODS: Outpatients (N = 40) with PTSD + MDD and at least moderate global severity were enrolled. 5 Hz rTMS included up to 40 daily sessions followed by a 5-session taper. Symptoms were measured using the PTSD Checklist (PCL-5) and Inventory of Depressive Symptomatology, Self-Report (IDS-SR). Baseline-to-endpoint changes were analyzed. RESULTS: The intent-to-treat population included 35 participants. Stimulation significantly reduced PTSD symptoms (PCL-5 baseline mean ±â€¯SD score 52.2 ±â€¯13.1 versus endpoint 34.0 ±â€¯21.6; p < .001); 23 patients (48.6%) met a pre-defined categorical PTSD response criteria. MDD symptoms also improved significantly (IDS-SR, baseline 47.8 ±â€¯11.9 to endpoint 30.9 ±â€¯18.9; p < .001); 15 patients (42.9%) demonstrated categorical response and 12 (34.3%) remitted. PTSD and MDD symptom change was highly correlated (r = 0.91, p < .001). LIMITATIONS: Unblinded single-arm study, with modest sample size. CONCLUSION: Significant and clinically meaningful reductions in both MDD and PTSD symptoms were observed following stimulation. The preliminary efficacy of 5 Hz rTMS for both symptom domains in patients with comorbid disorders supports future controlled studies.

Ethical decision-making regarding infant viability: A discussion.

BACKGROUND:: There are no universally agreed rules of healthcare ethics. Ethical decisions and standards tend to be linked to professional codes of practice when dealing with complex issues. OBJECTIVES:: This paper aims to explore the ethical complexities on who should decide to give infants born on the borderline of viability lifesaving treatment, parents or the healthcare professionals. METHOD:: The paper is a discussion using the principles of ethics, professional codes of practice from the UK, Nursing Midwifery Council and UK legal case law and statute. Healthcare professionals' experiences that influence parental decision are also considered. FINDINGS & DISCUSSION:: There are considerable barriers to an effective discussion taking place in an environment where clinical decisions have to be made quickly once the baby is born. This is compounded by the need and respect for parental autonomy and the difficulties they face when making a best interest's decision knowing that this could cause more harm than good for their infant child and balancing any decision they make with quality of life. CONCLUSION:: On deciding whether to give lifesaving treatment born at the borderline of viability, it should be a joint decision between the parents and the neonatal team.

Spatial Dependence of DNA Damage in Bacteria due to Low-Temperature Plasma Application as Assessed at the Single Cell Level.

Low temperature plasmas (LTPs) generate a cocktail of reactive nitrogen and oxygen species (RNOS) with bactericidal activity. The RNOS however are spatially unevenly distributed in the plasma. Here we test the hypothesis that this distribution will affect the mechanisms underpinning plasma bactericidal activity focussing on the level of DNA damage in situ. For the first time, a quantitative, single cell approach was applied to assess the level of DNA damage in bacteria as a function of the radial distance from the centre of the plasma jet. Salmonella enterica on a solid, dry surface was treated with two types of LTP: an atmospheric-pressure dielectric barrier discharge plasma jet (charged and neutral species) and a radio-frequency atmospheric-pressure plasma jet (neutral species). In both cases, there was an inverse correlation between the degree of DNA damage and the radial distance from the centre of the plasma, with the highest DNA damage occurring directly under the plasma. This trend was also observed with Staphylococcus aureus. LTP-generated UV radiation was eliminated as a contributing factor. Thus valuable mechanistic information can be obtained from assays on biological material, which can inform the development of LTP as a complementary or alternative therapy for (topical) bacterial infections.

Internal carotid arterial canal size and scaling in Euarchonta: Re-assessing implications for arterial patency and phylogenetic relationships in early fossil primates.

Primate species typically differ from other mammals in having bony canals that enclose the branches of the internal carotid artery (ICA) as they pass through the middle ear. The presence and relative size of these canals varies among major primate clades. As a result, differences in the anatomy of the canals for the promontorial and stapedial branches of the ICA have been cited as evidence of either haplorhine or strepsirrhine affinities among otherwise enigmatic early fossil euprimates. Here we use micro X-ray computed tomography to compile the largest quantitative dataset on ICA canal sizes. The data suggest greater variation of the ICA canals within some groups than has been previously appreciated. For example, Lepilemur and Avahi differ from most other lemuriforms in having a larger promontorial canal than stapedial canal. Furthermore, various lemurids are intraspecifically variable in relative canal size, with the promontorial canal being larger than the stapedial canal in some individuals but not others. In species where the promontorial artery supplies the brain with blood, the size of the promontorial canal is significantly correlated with endocranial volume (ECV). Among species with alternate routes of encephalic blood supply, the promontorial canal is highly reduced relative to ECV, and correlated with both ECV and cranium size. Ancestral state reconstructions incorporating data from fossils suggest that the last common ancestor of living primates had promontorial and stapedial canals that were similar to each other in size and large relative to ECV. We conclude that the plesiomorphic condition for crown primates is to have a patent promontorial artery supplying the brain and a patent stapedial artery for various non-encephalic structures. This inferred ancestral condition is exhibited by treeshrews and most early fossil euprimates, while extant primates exhibit reduction in one canal or another. The only early fossils deviating from this plesiomorphic condition are Adapis parisiensis with a reduced promontorial canal, and Rooneyia and Mahgarita with reduced stapedial canals.

Alterations of Mitochondrial DNA Copy Number and Telomere Length With Early Adversity and Psychopathology.

BACKGROUND: Telomere shortening and alterations of mitochondrial biogenesis are involved in cellular aging. Childhood adversity is associated with telomere shortening, and several investigations have shown short telomeres in psychiatric disorders. Recent studies have examined whether mitochondria might be involved in neuropsychiatric conditions; findings are limited and no prior work has examined this in relation to stress exposure. METHODS: Two-hundred ninety healthy adults provided information on childhood parental loss and maltreatment and completed diagnostic interviews. Participants were categorized into four groups based upon the presence or absence of childhood adversity and the presence or absence of lifetime psychopathology (depressive, anxiety, and substance use disorders). Telomere length and mitochondrial DNA (mtDNA) copy number were measured from leukocyte DNA by quantitative polymerase chain reaction. RESULTS: Childhood adversity and lifetime psychopathology were each associated with shorter telomeres (p < .01) and higher mtDNA copy numbers (p < .001). Significantly higher mtDNA copy numbers and shorter telomeres were seen in individuals with major depression, depressive disorders, and anxiety disorders, as well as those with parental loss and childhood maltreatment. A history of substance disorders was also associated with significantly higher mtDNA copy numbers. CONCLUSIONS: This study provides the first evidence of an alteration of mitochondrial biogenesis with early life stress and with anxiety and substance use disorders. We replicate prior work on telomere length and psychopathology and show that this effect is not secondary to medication use or comorbid medical illness. Finally, we show that early life stress and psychopathology are each associated with these markers of cellular aging.

Pavlovian contextual and instrumental biconditional discrimination learning in mice.

Genetically-modified animal models are a powerful tool for investigating the link between neurological and behavioral changes and for the development of therapeutic interventions. Executive function deficits are symptomatic of many human clinical disorders but few tasks exist for studying executive functions in mice. To address this need, we describe procedures for establishing Pavlovian contextual and instrumental biconditional discriminations (BCDs) in C57BL/6J mice. In the first experiment, contextual cues disambiguated when two short duration stimulus targets would be followed by food pellets. In the second experiment, discrete visual cues signaled when lever press or nose poke responses would be continuously reinforced with food pellets. Mice learned both BCDs as evidenced by differential responding in each cue during training and, more critically, during extinction testing. The implications of these findings for using BCD tasks to analyze the neural substrates of executive processing in animal models are discussed.