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Testicular Adrenal Rest Tumors: Current Insights on Prevalence, Characteristics, Origin, and Treatment
Abstract
This review provides the reader with current insights on testicular adrenal rest tumors (TARTs), a complication in male patients with congenital adrenal hyperplasia (CAH). In recent studies, an overall TART prevalence of 40% (range, 14% to 89%) in classic patients with CAH is found. Reported differences are mainly caused by the method of detection and the selected patient population. Biochemically, histologically, and molecularly, TARTs exhibit particular adrenal characteristics and were therefore thought to originate from aberrant adrenal cells. More recently, TARTs have been found to also exhibit testicular characteristics. This has led to the hypothesis of pluripotent cells as the origin of TARTs. High concentrations of ACTH could cause hyperplasia of these pluripotent cells, as TARTs appear to be associated with poor hormonal control with concomitant elevated ACTH. Unfortunately, as yet there are no methods to prevent the development of TARTs, nor are there guidelines to treat patients with TARTs. Intensified glucocorticoid treatment could improve fertility status in some cases, although studies report contradicting results. TARTs can also lead to irreversible testicular damage, and therefore semen cryopreservation could be offered to patients with TARTs. Further research should focus on the etiology and pharmacological treatment to prevent TART development or to treat TARTs and improve the fertility status of patients with TARTs.
Journal Article
Induction of altered states of consciousness during Floatation-REST is associated with the dissolution of body boundaries and the distortion of subjective time
Floatation-REST (Reduced Environmental Stimulation Therapy) minimizes stimulation of the nervous system by immersing subjects in an environment without sound or light while they effortlessly float in thermoneutral water supersaturated with Epsom salt. Here we investigated the relationship between altered states of consciousness (ASC) and its association with the affective changes induced by Floatation-REST. Using a within-subject crossover design, 50 healthy subjects were randomized to 60 min of Floatation-REST or 60 min of Bed-REST (an active control condition that entailed lying supine on a warm waterbed in a dark and quiet room). Following Floatation-REST, subjects felt significantly more relaxed, less anxious, and less tired than after Bed-REST. Floatation-REST also induced significantly more pronounced ASC characterized by the dissolution of body boundaries and the distortion of subjective time. The loss of body boundaries mediated the loss of anxiety, revealing a novel mechanism by which Floatation-REST exerts its anxiolytic effect.
Journal Article
Rest : why you get more done when you work less
\"For most of us, overwork is the new normal and rest is an afterthought. In our busy lives, rest is defined as the absence of work: late-night TV binges, hours spent trawling the internet, something to do once we've finished everything else on our to-do lists. But dismissing rest stifles our ability to think creatively and truly recharge. In Rest, Silicon Valley consultant Alex Pang argues that we can be more successful in all areas of our lives by recognizing the importance of rest: working better does not mean working more, it means working less and resting better. Treating rest as a passive activity secondary to work undermines our chances for a rewarding and meaningful life. Whether by making space for daily naps, as Winston Churchill did during World War II; going on hours-long strolls like Charles Darwin; or spending a week alone in a cabin like Bill Gates, pursuing what Pang calls \"deliberate rest\" is the true key to fulfillment and creative success. Drawing on rigorous scientific evidence and revelatory historical examples, Rest overturns everything our culture has taught us about work and shows that only by resting better can we start living better\"-- Provided by publisher.
BOOK
Reduced default mode network functional connectivity in patients with recurrent major depressive disorder
Major depressive disorder (MDD) is common and disabling, but its neuropathophysiology remains unclear. Most studies of functional brain networks in MDD have had limited statistical power and data analysis approaches have varied widely. The REST-meta-MDD Project of resting-state fMRI (R-fMRI) addresses these issues. Twenty-five research groups in China established the REST-meta-MDD Consortium by contributing R-fMRI data from 1,300 patients with MDD and 1,128 normal controls (NCs). Data were preprocessed locally with a standardized protocol before aggregated group analyses. We focused on functional connectivity (FC) within the default mode network (DMN), frequently reported to be increased in MDD. Instead, we found decreased DMN FC when we compared 848 patients with MDD to 794 NCs from 17 sites after data exclusion. We found FC reduction only in recurrent MDD, not in first-episode drug-naïve MDD. Decreased DMN FC was associated with medication usage but not with MDD duration. DMN FC was also positively related to symptom severity but only in recurrent MDD. Exploratory analyses also revealed alterations in FC of visual, sensory-motor, and dorsal attention networks in MDD. We confirmed the key role of DMN in MDD but found reduced rather than increased FC within the DMN. Future studies should test whether decreased DMN FC mediates response to treatment. All R-fMRI indices of data contributed by the REST-meta-MDD consortium are being shared publicly via the R-fMRI Maps Project.
Journal Article
Why we dream : the transformative power of our nightly journey
Science journalist and lucid dreamer Alice Robb examines why we dream and how we can improve our dream life.
Book
Intermittent versus continuous enteral nutrition attenuates increases in insulin and leptin during short-term bed rest
PurposeTo compare endocrine responses to intermittent vs continuous enteral nutrition provision during short-term bed rest.MethodsTwenty healthy men underwent 7 days of bed rest, during which they were randomized to receive enteral nutrition (47%E as carbohydrate, 34%E as fat, 16%E as protein and 3%E as fibre) in a continuous (CONTINUOUS; n = 10; 24 h day−1 at a constant rate) or intermittent (INTERMITTENT; n = 10; as 4 meals per day separated by 5 h) pattern. Daily plasma samples were taken every morning to assess metabolite/hormone concentrations.ResultsDuring bed rest, plasma leptin concentrations were elevated to a lesser extent with INTERMITTENT vs CONTINUOUS (iAUC: 0.42 ± 0.38 vs 0.95 ± 0.48 nmol L−1, respectively; P = 0.014) as were insulin concentrations (interaction effect, P < 0.001) which reached a peak of 369 ± 225 pmol L−1 in CONTINUOUS, compared to 94 ± 38 pmol L−1 in INTERMITTENT (P = 0.001). Changes in glucose infusion rate were positively correlated with changes in fasting plasma GLP-1 concentrations (r = 0.44, P = 0.049).ConclusionIntermittent enteral nutrition attenuates the progressive rise in plasma leptin and insulinemia seen with continuous feeding during bed rest, suggesting that continuous feeding increases insulin requirements to maintain euglycemia. This raises the possibility that hepatic insulin sensitivity is impaired to a greater extent with continuous versus intermittent feeding during bed rest. To attenuate endocrine and metabolic changes with enteral feeding, an intermittent feeding strategy may, therefore, be preferable to continuous provision of nutrition.This trial was registered on clinicaltrials.gov as NCT02521025.
Journal Article
Exercise-induced changes in brain activity during memory encoding and retrieval after long-term bed rest
Episodic memory depends decisively on the hippocampus and the parahippocampal gyrus, brain structures that are also prone to exercise-induced neuroplasticity and cognitive improvement. We conducted a randomized controlled trial to investigate the effects of a high-intensity exercise program in twenty-two men resting in bed for 60 days on episodic memory and its neuronal basis. All participants were exposed to 60 days of uninterrupted bed rest. Eleven participants were additionally assigned to a high-intensity interval training that was performed five to six times weekly for 60 days. Episodic memory and its neural basis were determined four days prior to and on the 58th day of bed rest using functional magnetic resonance imaging (fMRI). We found increased BOLD signal in the left hippocampus and parahippocampal gyrus in the non-exercising group compared to the exercising bed rest group whereas the mnemonic performance did not differ significantly. These findings indicate a higher neuronal efficiency in the training group during memory encoding and retrieval and may suggest a dysfunctional mechanism in the non-exercising bed rest group induced by two months of physical inactivity. Our results provide further support for the modulating effects of physical exercise and adverse implications of a sedentary lifestyle and bedridden patients.
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Journal Article
Sensory-motor cortices shape functional connectivity dynamics in the human brain
Large-scale biophysical circuit models provide mechanistic insights into the micro-scale and macro-scale properties of brain organization that shape complex patterns of spontaneous brain activity. We developed a spatially heterogeneous large-scale dynamical circuit model that allowed for variation in local synaptic properties across the human cortex. Here we show that parameterizing local circuit properties with both anatomical and functional gradients generates more realistic static and dynamic resting-state functional connectivity (FC). Furthermore, empirical and simulated FC dynamics demonstrates remarkably similar sharp transitions in FC patterns, suggesting the existence of multiple attractors. Time-varying regional fMRI amplitude may track multi-stability in FC dynamics. Causal manipulation of the large-scale circuit model suggests that sensory-motor regions are a driver of FC dynamics. Finally, the spatial distribution of sensory-motor drivers matches the principal gradient of gene expression that encompasses certain interneuron classes, suggesting that heterogeneity in excitation-inhibition balance might shape multi-stability in FC dynamics.
Spontaneous fluctuations in brain activity exhibit complex spatiotemporal patterns across animal species. Here the authors show that sensory-motor regions and spatial heterogeneity in excitation-inhibition balance might shape multi-stability in brain dynamics.
Journal Article