Hallucinatory experiences can occur in both clinical and nonclinical groups. However, in previous studies of the general population, investigations of the cognitive mechanisms underlying ...hallucinatory experiences have yielded inconsistent results. We ran a large-scale preregistered multisite study, in which general-population participants (N = 1,394 across 11 data-collection sites and online) completed assessments of hallucinatory experiences, a measure of adverse childhood experiences, and four tasks: source memory, dichotic listening, backward digit span, and auditory signal detection. We found that hallucinatory experiences were associated with a higher false-alarm rate on the signal detection task and a greater number of reported adverse childhood experiences but not with any of the other cognitive measures employed. These findings are an important step in improving reproducibility in hallucinations research and suggest that the replicability of some findings regarding cognition in clinical samples needs to be investigated.
Hallucinatory experiences can occur in both clinical and nonclinical groups. However, in previous studies of the general population, investigations of the cognitive mechanisms underlying ...hallucinatory experiences have yielded inconsistent results. We ran a large-scale preregistered multisite study, in which general-population participants ( N = 1,394 across 11 data-collection sites and online) completed assessments of hallucinatory experiences, a measure of adverse childhood experiences, and four tasks: source memory, dichotic listening, backward digit span, and auditory signal detection. We found that hallucinatory experiences were associated with a higher false-alarm rate on the signal detection task and a greater number of reported adverse childhood experiences but not with any of the other cognitive measures employed. These findings are an important step in improving reproducibility in hallucinations research and suggest that the replicability of some findings regarding cognition in clinical samples needs to be investigated.
Hallucinatory experiences can occur in both clinical and nonclinical groups. However, in previous studies of the general population, investigations of the cognitive mechanisms underlying ...hallucinatory experiences have yielded inconsistent results. We ran a large-scale preregistered multisite study, in which general-population participants ( N = 1,394 across 11 data-collection sites and online) completed assessments of hallucinatory experiences, a measure of adverse childhood experiences, and four tasks: source memory, dichotic listening, backward digit span, and auditory signal detection. We found that hallucinatory experiences were associated with a higher false-alarm rate on the signal detection task and a greater number of reported adverse childhood experiences but not with any of the other cognitive measures employed. These findings are an important step in improving reproducibility in hallucinations research and suggest that the replicability of some findings regarding cognition in clinical samples needs to be investigated.
Hallucinatory experiences (HEs) can be pronounced in psychosis, but similar experiences also occur in nonclinical populations. Cognitive mechanisms hypothesized to underpin HEs include dysfunctional ...source monitoring, heightened signal detection, and impaired attentional processes. Using data from an international multisite study on non-clinical participants (N = 419), we described the overlap between two sets of variables - one measuring cognition and the other HEs - at the level of individual items. We used a three-step method to extract and examine item-specific signal, which is typically obscured when summary scores are analyzed using traditional methodologies. The three-step method involved: (1) constraining variance in cognition variables to that which is predictable from HE variables, followed by dimension reduction, (2) determining reliable HE items using split-halves and permutation tests, and (3) selecting cognition items for interpretation using a leave-one-out procedure followed by repetition of Steps 1 and 2. The results showed that the overlap between HEs and cognition variables can be conceptualized as bi-dimensional, with two distinct mechanisms emerging as candidates for separate pathways to the development of HEs: HEs involving perceptual distortions on one hand (including voices), underpinned by a low threshold for signal detection in cognition, and HEs involving sensory overload on the other hand, underpinned by reduced laterality in cognition. We propose that these two dimensions of HEs involving distortions/liberal signal detection, and sensation overload/reduced laterality may map onto psychosis-spectrum and dissociation-spectrum anomalous experiences, respectively.
Hallucinations are often seen as a serious symptom of mental illness. Nonetheless, recent decades have produced a body of evidence that documented the presence of hallucinations even in non-clinical ...samples. Therefore, focusing on these samples is critical for improving understanding of processes underlying auditory hallucinations. The present study examines cognitive mechanisms that have been proposed to influence proneness to auditory hallucinations. A battery of experimental measures is implemented to assess some of the mechanisms implicated in the aetiology of hallucinations. Source monitoring, cognitive inhibition, bottom-up processes, working memory and traumatic experiences were measured in a laboratory study of 52 participants. Findings suggest that proneness to hallucinations is associated with impaired top-down processing and early traumatic experiences. No association between other cognitive mechanisms and hallucination proneness, contrary to previous evidence, has been found. This indicates that impaired source memory, working memory and bottom-up processing impairments might distinguish clinical and non-clinical hallucinators. An alternative implication of these findings points at issues with reproducibility in the hallucination research. Keywords: Auditory verbal hallucinations,...
Polycystic kidney diseases (PKDs) are genetic disorders that can cause renal failure and death in children and adults. Lowering cAMP in cystic tissues through the inhibition of the type-2 vasopressin ...receptor (V2R) constitutes a validated strategy to reduce disease progression. We identified a peptide from green mamba venom that exhibits nanomolar affinity for the V2R without any activity on 155 other G-protein–coupled receptors or on 15 ionic channels. Mambaquaretin-1 is a full antagonist of the V2R activation pathways studied: cAMP production, beta-arrestin interaction, and MAP kinase activity. This peptide adopts the Kunitz fold known to mostly act on potassium channels and serine proteases. Mambaquaretin-1 interacts selectively with the V2R through its first loop, in the same manner that aprotinin inhibits trypsin. Injected in mice, mambaquaretin-1 increases in a dose-dependent manner urine outflow with concomitant reduction of urine osmolality, indicating a purely aquaretic effect associated with the in vivo blockade of V2R. CD1-pcy/pcy mice, a juvenile model of PKD, daily treated with 13 μg of mambaquaretin-1 for 99 d, developed less abundant (by 33%) and smaller (by 47%) cysts than control mice. Neither tachyphylaxis nor apparent toxicity has been noted. Mambaquaretin-1 represents a promising therapeutic agent against PKDs.
Aldosterone effects are mediated by the mineralocorticoid receptor (MR), a transcription factor highly expressed in the distal nephron. Given that MR expression level constitutes a key element ...controlling hormone responsiveness, there is much interest in elucidating the molecular mechanisms governing MR expression. To investigate whether hyper- or hypotonicity could affect MR abundance, we established by targeted oncogenesis a novel immortalized cortical collecting duct (CCD) cell line and examined the impact of osmotic stress on MR expression. KC3AC1 cells form domes, exhibit a high transepithelial resistance, express 11β-hydroxysteroid dehydrogenase 2 and functional endogenous MR, which mediates aldosterone-stimulated Na+ reabsorption through the epithelial sodium channel activation. MR expression is tightly regulated by osmotic stress. Hypertonic conditions induce expression of tonicity-responsive enhancer binding protein, an osmoregulatory transcription factor capable of binding tonicity-responsive enhancer response elements located in MR regulatory sequences. Surprisingly, hypertonicity leads to a severe reduction in MR transcript and protein levels. This is accompanied by a concomitant tonicity-induced expression of Tis11b, a mRNA-destabilizing protein that, by binding to the AU-rich sequences of the 3′-untranslated region of MR mRNA, may favor hypertonicity-dependent degradation of labile MR transcripts. In sharp contrast, hypotonicity causes a strong increase in MR transcript and protein levels. Collectively, we demonstrate for the first time that optimal adaptation of CCD cells to changes in extracellular fluid composition is accompanied by drastic modification in MR abundance via transcriptional and posttranscriptional mechanisms. Osmotic stress-regulated MR expression may represent an important molecular determinant for cell-specific MR action, most notably in renal failure, hypertension, or mineralocorticoid resistance.
Osmotic stress regulates mineralocorticoid receptor expression in cortical collecting duct cells.
This study aimed to describe the clinical characteristics of maternal deaths associated with COVID-19 registered in a collaborative Latin-American multi-country database.
This was an observational ...study implemented from March 1st 2020 to November 29th 2021 in eight Latin American countries. Information was based on the Perinatal Information System from the Latin American Center for Perinatology, Women and Reproductive Health. We summarized categorical variables as frequencies and percentages and continuous variables into median with interquartile ranges.
We identified a total of 447 deaths. The median maternal age was 31 years. 86·4% of women were infected antepartum, with most of the cases (60·3%) detected in the third trimester of pregnancy. The most frequent symptoms at first consultation and admission were dyspnea (73·0%), fever (69·0%), and cough (59·0%). Organ dysfunction was reported in 90·4% of women during admission. A total of 64·8% women were admitted to critical care for a median length of eight days. In most cases, the death occurred during the puerperium, with a median of seven days between delivery and death. Preterm delivery was the most common perinatal complication (76·9%) and 59·9% were low birth weight.
This study describes the characteristics of maternal deaths in a comprehensive multi-country database in Latin America during the COVID-19 pandemic. Barriers faced by Latin American pregnant women to access intensive care services when required were also revealed. Decision-makers should strengthen severity awareness, and referral strategies to avoid potential delays.
Latin American Center for Perinatology, Women and Reproductive Health.
Significance Polycystic kidney diseases (PKDs) are genetic disorders in which multiple cysts grow in kidneys, leading to end-stage renal failure. Vasopressin antagonists (vaptans) currently used to ...treat PKDs have side effects due to liver toxicity. We report the characterization of Mambaquaretin-1, a Kunitz-fold polypeptide isolated from mamba venom that selectively and fully inhibits three major signaling pathways of the vasopressin type-2 receptor. Mambaquaretin-1 induces a purely aquaretic effect on mice and reduces cyst development in a mouse model. We produced mambaquaretin-1 by peptide synthesis and determined its X-ray structure, its binding mode, and functional properties. With high selectivity and without toxic metabolic byproducts associated with its peptidic nature, mambaquaretin-1 could become the preferential treatment for these disorders.
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