Background: Stressful life events can both trigger development of psychiatric disorders and promote positive behavioral changes in response to adversities. The relationship between stress and cognitive flexibility is complex, and conflicting effects of stress manifest in both humans and laboratory animals.
Objective: To mirror the clinical situation where stressful life events impair mental health or promote behavioral change, we examined the post-exposure effects of stress on cognitive flexibility in mice.
Psychedelic-assisted psychotherapy holds great promise in the treatment of mental health disorders. Research into 5-hydroxytryptamine 2A receptor (5-HTR) agonist psychedelic compounds has increased dramatically over the past two decades. In humans, these compounds produce drastic effects on consciousness, and their therapeutic potential relates to changes in the processing of emotional, social, and self-referential information.
View Article and Find Full Text PDFOptimal foraging models predict that individual animals will optimize net energy gain by intensifying forage activity and/or reducing forage energy cost. Then, the free distribution model predicts an animal's distribution in a patchy landscape will match the distribution of the resources. If not modified by other factors, such patterns may be expected to be particularly explicit in variable and extreme, forage-limited, and patchy environments, notably alpine and Arctic environments during winter.
View Article and Find Full Text PDFPsychedelic 5-hydroxytryptamine 2A receptor (5-HT2AR) agonists are showing promise in the treatment of psychiatric disorders, such as treatment-resistant depression and anxiety. Human studies suggest that enhanced cognitive flexibility may contribute to their clinical efficacy. Both improvement and impairment of cognitive flexibility has been reported with 5-HT2AR ligands, making the link between 5-HT2AR pharmacology and cognitive flexibility equivocal.
View Article and Find Full Text PDFPsychedelic drugs acting as 5-hydroxyptryptamine 2A receptor (5-HTR) agonists have shown promise as viable treatments of psychiatric disorders, including obsessive-compulsive disorder. The marble burying test is a test of compulsive-like behavior in mice, and psychedelics acting as 5-HTR agonists can reduce digging in this test. We assessed the 5-HTR contribution to the mechanisms of two 5-HT agonists on digging behavior in female NMRI mice, using citalopram as a reference compound.
View Article and Find Full Text PDFPsychopharmacology (Berl)
February 2021
Rationale: The widespread deficits in cognitive flexibility observed across psychiatric disorders call for improved rodent tests to understand the biology of cognitive flexibility and development of better psychotherapeutics. Current reversal learning paradigms have a forced-choice setup that challenges the interpretation of results.
Objectives: We aimed at developing a free-choice reversal learning test, where images are presented sequentially and animals are free to move, to enable investigation of the cognitive sub-processes that occur during reversal.
The boundary between the boreal and arctic biomes in northwest Europe has been a matter of debate for many years. Some authors consider that the boundary is marked by the northern limit of tree growth in the northernmost Norwegian mainland. In this study we have collected air and soil temperature data from 37 heath stands from northern Finnmark (71°N), the northernmost part of the Norwegian mainland, through Bear Island (74°N) in the Barents sea, to Adventsdalen (78)°N (in Spitsbergen) in Svalbard archipelago.
View Article and Find Full Text PDFThe remarkable effects exhibited by classical psychedelics in recent clinical trials have spawned considerable interest in 5-HT receptor (5-HTR) activation as a treatment strategy for several psychiatric/cognitive disorders. In this study we have continued our development of 25CN-NBOH, one of the most 5-HTR-selective agonists reported to date, as a pharmacological tool for exploration of 5-HTR expression and functions. The importance of the 2' and 3' positions in 25CN-NBOH as structural hotspots for its 5-HTR activity was investigated by synthesis and pharmacological characterization of six novel analogs at 5-HTR and 5-HTR in binding and functional assays.
View Article and Find Full Text PDFTidsskr Nor Laegeforen
March 2020
Background: Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) syndrome is an immune-mediated, treatable and inflammatory CNS disease first reported by Pittock et al. (2010).
Case Presentation: We describe a 66-year-old man with previous history of diabetes, atrial fibrillation and hypertension, who was admitted to hospital with reduced general condition.
Lysergic acid diethylamide (LSD) is a prototypical serotonergic psychedelic drug and the subject of many clinical investigations. In recent years, a range of lysergamides has emerged with the production of some being inspired by the existing scientific literature. Others, for example various 1-acyl substituted lysergamides, did not exist before their appearance as research chemicals.
View Article and Find Full Text PDFBackground: The aim of this study was to investigate changes in structural magnetic resonance imaging (MRI) according to the RANO criteria and perfusion- and permeability related metrics derived from dynamic contrast-enhanced MRI (DCE) and dynamic susceptibility contrast MRI (DSC) during radiochemotherapy for prediction of progression and survival in glioblastoma.
Methods: Twenty-three glioblastoma patients underwent biweekly structural and perfusion MRI before, during, and two weeks after a six weeks course of radiochemotherapy. Temporal trends of tumor volume and the perfusion-derived parameters cerebral blood volume (CBV) and blood flow (CBF) from DSC and DCE, in addition to contrast agent capillary transfer constant (K) from DCE, were assessed.
5-Hydroxytryptamine 2A receptor (5-HTR) agonist psychedelics are increasingly recognized as potentially useful treatments of psychiatric disorders, such as obsessive-compulsive disorder, depression, anxiety, and drug dependence. There is limited understanding of the way they exert their therapeutic action, but inhibition of rigid behavior and cognition has been suggested as a key factor. To examine the role of 5-HTRs in modulating repetitive behavior, we tested two 5-HTR agonists, DOI, and the selective 25CN-NBOH, in two mouse tests of compulsive-like behavior.
View Article and Find Full Text PDFRodents exhibit natural exploratory behaviors, which can be measured by the spontaneous alternation behavior (SAB) test. Perseverance in this test induced by the 5-hydroxytryptamine 1A receptor (5-HTR) agonist, 8-hydroxy-2-dipropylaminotetralin (8-OH-DPAT), resembles compulsive behaviors observed in humans and manifests as reduced alternation ratio. This study characterized 8-OH-DPAT-induced perseverance in the SAB test in C57BL/6JOlaHsd male mice by coadministration of WAY100635, citalopram and the 5-HT releasing agent, 3,4-methylenedioxymethamphetamine (MDMA), to deepen the understanding of 5-HT-dependent mechanisms.
View Article and Find Full Text PDFFracture of the tibial tray is a rarely observed complication of total knee arthroplasty (TKA), predominately in implants placed greater than a decade ago. This case highlights a case of baseplate fracture in a contemporary prosthesis. The patient presented 1 year after TKA with medial knee pain consistent with pes bursitis.
View Article and Find Full Text PDFGlobally accelerating trends in societal development and human environmental impacts since the mid-twentieth century are known as the Great Acceleration and have been discussed as a key indicator of the onset of the Anthropocene epoch . While reports on ecological responses (for example, changes in species range or local extinctions) to the Great Acceleration are multiplying , it is unknown whether such biotic responses are undergoing a similar acceleration over time. This knowledge gap stems from the limited availability of time series data on biodiversity changes across large temporal and geographical extents.
View Article and Find Full Text PDFMammalian herbivores have important top-down effects on ecological processes and landscapes by generating vegetation changes through grazing and trampling. For free-ranging herbivores on large landscapes, trampling is an important ecological factor. However, whereas grazing is widely studied, low-intensity trampling is rarely studied and quantified.
View Article and Find Full Text PDFBackground: The use of a trabecular metal revision shell with metal augmentation to fill segmental or irregular defects during complex revision hip arthroplasty has been shown to provide good short-term results in prior published series. Longer-term results of the several cup-augment constructs used clinically are not known. The objective of this study was to report, with minimum 5-year radiographic and clinical follow-up, the outcome of these various constructs in revision total hip arthroplasty.
View Article and Find Full Text PDFObjective: The current study investigated expert beliefs and practices as they relate to neuropsychological validity testing.
Methods: North American neuropsychologists with expertise in neuropsychological validity testing (n = 24) were surveyed on numerous items related to validity testing. Results were analyzed and compared to findings from a prior expert survey and a recent survey of a general sample of neuropsychological practitioners.
Patients who suffer acute ischaemic stroke can be treated with thrombolysis if therapy is initiated early. Radiological evaluation of the intracranial tissue before such therapy can be given is mandatory. In this review current radiological diagnostic strategies are discussed for this patient group.
View Article and Find Full Text PDFObjective: The current study investigated changes in neuropsychologists' validity testing beliefs and practices since publication of the last North American survey targeting these issues in 2007 and explored emerging issues in validity testing that had not been previously addressed in the professional survey literature.
Methods: Licensed North American neuropsychologists (n = 316), who primarily evaluate adults, were surveyed in regard to the following topics: (1) comparison of objective validity testing, qualitative data, and clinical judgment; (2) approaches to validity test administration; (3) formal communication in cases of suspected malingering; (4) reporting of validity test results; (5) suspected causes of invalidity; (6) integration of stand-alone, embedded, and symptom-report validity measures; (7) multiple performance validity test interpretation; (8) research practices; and (9) popularity of specific validity instruments.
Results: Overall, findings from the current survey indicated that all but a small minority of respondents routinely utilize validity testing in their examinations.
Background: Up to 25% of stroke patients wake up with a neurological deficit, so called wake-up stroke (WUS). Different imaging approaches that may aid in the selection of patients likely to benefit from reperfusion therapy are currently under investigation. The magnetic resonance imaging (MRI) diffusion weighted imaging - fluid attenuated inversion recovery (DWI-FLAIR) mismatch concept is one proposed method for identifying patients presenting within 4.
View Article and Find Full Text PDFMonte Carlo simulations were utilized to determine the proportion of the normal population expected to have scale elevations on the MMPI-2-RF when multiple scores are interpreted. Results showed that when all 40 MMPI-2-RF scales are simultaneously considered, approximately 70% of normal adults are likely to have at least one scale elevation at or above 65 T, and as many as 20% will have five or more elevated scales. When the Restructured Clinical (RC) Scales are under consideration, 34% of normal adults have at least one elevated score.
View Article and Find Full Text PDFAlthough dual-mobility sockets have been in clinical use for decades in other parts of the world, they recently gained popularity in the United States as an option for primary and revision total hip arthroplasty (THA). Improvements in dual-mobility socket technology include articulation with a metal insert impacted into a metal shell and a femoral head made of highly cross-linked polyethylene. The results and complications associated with the use of dual-mobility sockets employing these technologic advancements are not known.
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