Differential effects of high-fat diet on endocrine, metabolic and depressive-like behaviors in male and female rats.

The complications of obesity extend beyond the periphery to the central nervous system (CNS) and include an increased risk of developing neuropsychiatric co-morbidities like depressive illness. Preclinical studies support this concept, including studies that have examined the effects of a high-fat diet (HFD) on depressive-like behaviors. Although women are approximately two-fold more likely to develop depressive illness compared to men, most preclinical studies have focused on the effects of HFD in male rodents. Accordingly, the goal of this study was to examine depressive-like behaviors in male and female rats provided access to a HFD. In agreement with prior studies, male and female rats provided a HFD segregate into an obesity phenotype (i.e., diet-induced obesity; DIO) or a diet resistant (DR) phenotype. Upon confirmation of the DR and DIO phenotypes, behavioral assays were performed in control chow, DR, and DIO rats. In the sucrose preference test, male DIO rats exhibited significant decreases in sucrose consumption (i.e., anhedonia) compared to male DR and male control rats. In the forced swim test (FST), male DIO rats exhibited increases in immobility and decreases in climbing behaviors in the pre-test sessions. Interestingly, male DR rats exhibited these same changes in both the pre-test and test sessions of the FST, suggesting that consumption of a HFD, even in the absence of the development of an obesity phenotype, has behavioral consequences. Female rats did not exhibit differences in sucrose preference, but female DIO rats exhibited increases in immobility exclusively in the test session of the FST, behavioral changes that were not affected by the stage of the estrous cycle. Collectively, these studies demonstrate that access to a HFD elicits different behavioral outcomes in male and female rats.

Pyridostigmine bromide and stress interact to impact immune function, cholinergic neurochemistry and behavior in a rat model of Gulf War Illness.

Gulf War Illness (GWI) is characterized by a constellation of symptoms that includes cognitive dysfunction. While the causes for GWI remain unknown, prophylactic use of the acetylcholinesterase inhibitor pyridostigmine bromide (PB) in combination with the stress of deployment has been proposed to be among the causes of the cognitive dysfunction in GWI. Mechanistically, clinical studies suggest that altered immune function may be an underlying factor in the neurochemical and neurobehavioral complications of GWI. Accordingly, the goal of this study was to determine how responses to an immune challenge (lipopolysaccharide; LPS) or stress impacts inflammation, acetylcholine (ACh) neurochemistry and behavior in an experimental model of GWI. Rats with a history of PB treatment exhibited potentiated increases in C-reactive protein levels in response to a submaximal LPS challenge compared to control rats, indicating that prior treatment with this cholinesterase inhibitor leads to exacerbated inflammatory responses to a subsequent immune challenge. ACh responses to LPS administration were decreased in the hippocampus, but not prefrontal cortex (PFC), in rats with a prior history of PB treatment or stress exposure. Additionally, ACh release in response to acute immobilization stress was attenuated in the PFC and hippocampus in these groups. These attenuated cholinergic responses were accompanied by impairments in contextual and cue-based fear learning. The results of this study suggest that stress and LPS challenges adversely affect central ACh neurochemistry in a rodent model of GWI and support the hypothesis that dysregulated immune responses are mechanistically linked to the neurological complications of GWI.

Carbohydrate Loading Practice in Bodybuilders: Effects on Muscle Thickness, Photo Silhouette Scores, Mood States and Gastrointestinal Symptoms.

A common practice among bodybuilders is the use of carbohydrate loading to improve physical appearance during competition, while limited documented data is available about this issue. The aim of the present study was to evaluate muscle thickness, mood states, gastrointestinal symptoms and subjective silhouette assessment following carbohydrate loading in bodybuilders. Twenty-four male bodybuilders were evaluated at the weighing period following three days of carbohydrate depletion (M1), and 24h of carbohydrate loading leading up to the competition (M2), stratified into: no carbohydrate load (NC, n = 9) and carbohydrate loading (CL, n =1 5). The silhouette scale, Brunel mood scale (BRUMS), muscle thickness (ultrasound), circumferences, and gastrointestinal symptoms (GIS) were evaluated at M1 and M2. The NC displayed no differences in muscle thickness and circumferences between M1 and M2. Body mass, muscle thickness (elbow flexors, a combination of biceps brachii/ brachialis muscle, and triceps brachii) and circumferences (chest, hip, thigh, arm, calves, and forearm) increased significantly (p < 0.05) in the CL at M2. There was a significant increase in photo silhouette scores (p < 0.05) in the CL at M2. There was no significant difference in mood states between groups or time. The most reported GIS was constipation: 7/9 (NC) and 9/15 (CL) during M1 and 6/9 (NC), and 5/15 (CL) at M2 with symptoms described as 'moderate' or 'severe'. Diarrhea was reported by 7/15 CL (4/15 as severe). These data suggest that carbohydrate loading may contribute to an acute increase in muscle volume and physical appearance, however, it needs to be better planned to minimize gastrointestinal symptoms in bodybuilders.

Characteristics of CA1 place fields in a complex maze with multiple choice points.

For the sake of rigorous control of task variables, hippocampal place cells have been usually studied in relatively simple environments. To approach the situation of real-life navigation in an urban-like environment, we recorded CA1 place cells while rats performance a memory task in a "Townmaze" with two start locations, three alternate paths in the maze midsection, followed by a two-way choice that determined the trial outcome, access to a goal compartment. Further, to test the ability of place cells to update their spatial representation upon local changes in the environment while maintaining the integrity of the overall spatial map to allow effective navigation, we occasionally introduced barriers in the maze mid-section to force the rat to select a nonpreferred route. The "Townmaze" revealed many new interesting features of CA1 neurons. First, we found neurons with 3-5 fields that appear to represent segments on a single common route through the maze. Second, we found neurons with 3-5 fields similarly aligned along the longitudinal or transverse maze axis. Responses to the barriers were assessed separately near and far from the barriers. Appearance of new fields in response to the barriers took place almost exclusively only locally near the barrier, whereas in-field firing rate changes occurred throughout the maze. Further, field location changes did not correlate with the task performance, whereas firing rate changes did. These findings suggest that in a complex environment with blocked distal views, CA1 neurons code for the environment as sequences of significant nodes but are also capable of extracting and associating common elements across these sequences.

Leptin resistance elicits depressive-like behaviors in rats.

There is a growing appreciation that the complications of obesity extend to the central nervous system (CNS) and include increased risk for development of neuropsychiatric co-morbidities such as depressive illness. The neurological consequences of obesity may develop as a continuum and involve a progression of pathological features which is initiated by leptin resistance. Leptin resistance is a hallmark feature of obesity, but it is unknown whether leptin resistance or blockage of leptin action is casually linked to the neurological changes which underlie depressive-like phenotypes. Accordingly, the aim of the current study was to examine whether chronic administration of a pegylated leptin receptor antagonist (Peg-LRA) elicits depressive-like behaviors in adult male rats. Peg-LRA administration resulted in endocrine and metabolic features that are characteristic of an obesity phenotype. Peg-LRA rats also exhibited increased immobility in the forced swim test, depressive-like behaviors that were accompanied by indices of peripheral inflammation. These results demonstrate that leptin resistance elicits an obesity phenotype that is characterized by peripheral immune changes and depressive-like behaviors in rats, supporting the concept that co-morbid obesity and depressive illness develop as a continuum resulting from changes in the peripheral endocrine and metabolic milieu.

Shot-noise-limited monitoring and phase locking of the motion of a single trapped ion.

We perform a high-resolution real-time readout of the motion of a single trapped and laser-cooled Ba+ ion. By using an interferometric setup, we demonstrate a shot-noise-limited measurement of thermal oscillations with a resolution of 4 times the standard quantum limit. We apply the real-time monitoring for phase control of the ion motion through a feedback loop, suppressing the photon recoil-induced phase diffusion. Because of the spectral narrowing in the phase-locked mode, the coherent ion oscillation is measured with a resolution of about 0.3 times the standard quantum limit.

Validation of and Normative Data of the DVAQ-30, a New Video-Naming Test for Assessing Verb Anomia.

OBJECTIVE: Anomia is usually assessed using picture-naming tests. While many tests evaluate anomia for nouns, very few tests have been specifically designed for verb anomia. This article presents the DVAQ-30, a new naming test for detecting verb anomia in adults and elderly people. METHOD: The article describes three studies. Study 1 focused on the DVAQ-30 development phase. In Study 2, healthy participants and individuals with post-stroke aphasia, mild cognitive impairment, Alzheimer's disease, or primary progressive aphasia were assessed using the DVAQ-30 to establish its convergent and discriminant validity, test-retest reliability, and internal consistency. In Study 3, a group of adults and elderly Quebec French-speaking adults were assessed to obtain normative data. RESULTS: The DVAQ-30 had good convergent validity and distinguished the performance of healthy participants from that of participants with pathological conditions. The test also had good internal consistency, and the test-retest analysis showed that the scores had good temporal stability. Furthermore, normative data were collected on the performance of 244 participants aged 50 years old and over. CONCLUSIONS: The DVAQ-30 fills an important gap and has the potential to help clinicians and researchers better detect verb anomia associated with pathological aging and post-stroke aphasia.

Adaptations to water stress and pastoralism in the Turkana of northwest Kenya.

The Turkana people inhabit arid regions of east Africa-where temperatures are high and water is scarce-and they practice subsistence pastoralism, such that their diet is primarily composed of animal products. Working with Turkana communities, we sequenced 367 genomes and identified 8 regions putatively involved in adaptation to water stress and pastoralism. One of these regions includes a putative enhancer for STC1-a kidney-expressed gene involved in the response to dehydration and the metabolism of purine-rich foods such as red meat. We show that STC1 is induced by antidiuretic hormone in humans, is associated with urea levels in the Turkana themselves, and is under strong selection in this population (s∼0.041). This work highlights that partnerships with subsistence-level groups can lead to new models of human physiology with biomedical relevance.

The role of semantic memory in the recognition of emotional valence conveyed by written words.

The main goal of this study was to examine the role of semantic memory in the recognition of emotional valence conveyed by words. Eight participants presenting with the semantic variant of primary progressive aphasia (svPPA) and 33 healthy control participants were administered three tasks designed to investigate the formal association between the recognition of emotional valence conveyed by words and the lexical and semantic processing of these words. Results revealed that individuals with svPPA showed deficits in the recognition of negative emotional valence conveyed by words. Moreover, results evidenced that their performance in the recognition of emotional valence was better for correctly than for incorrectly retrieved lexical entries of words, while their performance was comparable for words that were correctly or incorrectly associated with semantic concepts. These results suggest that the recognition of emotional valence conveyed by words relies on the retrieval of lexical, but not semantic, representations of words.

Training Programs Designed for Muscle Hypertrophy in Bodybuilders: A Narrative Review.

Bodybuilding is a sport that requires adequate training strategies in order to maximize skeletal muscle hypertrophy. The purpose of the present review was to perform a narrative assessment of the training routines designed for muscle hypertrophy used by bodybuilders. A search was carried out in the databases Pubmed/MEDLINE, Scielo, EBSCO, LILACS, SportDiscus, Web of Science, and CINAHL with the words "Resistance training" and "hypertrophy" in bodybuilders and their variations that involve the respective outcomes. Fourteen studies were identified that investigated the long-term training routines of bodybuilders. These studies demonstrate a pattern in the training organization, whereby there is a separation of training into four distinct periods: off-season, pre-contest, peak week, and post-contest. Each period has a specific spectrum of intensity load, total training volume, and exercise type (multi- or single-joint). We conclude that bodybuilding competitors employed a higher intensity load, lower number of repetitions, and longer rest intervals in the off-season than pre-contest.

Disturbance and ecologic succession in an upper ordovician cobble-dwelling hardground fauna.

An Ordovician hardground fauna in northern Kentucky provides an example from the fossil record of the maintenance of species diversity by periodic disturbance of an autogenic ecologic succession. The marine invirtebrates found encrusting limestone cobbles show an order of community development from a low-diversity pioneer assemblage through a high-diversity association to a monospecific stable fauna. All species, including the late successional dominants, were present in the early stages of colonization. Periodic overturning of the cobbles killed the encrusters and opened up new spaces on which succession was reinitiated. These disturbances maintained high diversity within the encrusting community by limiting the spatial distribution of the most efficient space competitors.

Reactivation of hippocampal ensemble memories during sleep.

Simultaneous recordings were made from large ensembles of hippocampal "place cells" in three rats during spatial behavioral tasks and in slow-wave sleep preceding and following these behaviors. Cells that fired together when the animal occupied particular locations in the environment exhibited an increased tendency to fire together during subsequent sleep, in comparison to sleep episodes preceding the behavioral tasks. Cells that were inactive during behavior, or that were active but had non-overlapping spatial firing, did not show this increase. This effect, which declined gradually during each post-behavior sleep session, may result from synaptic modification during waking experience. Information acquired during active behavior is thus re-expressed in hippocampal circuits during sleep, as postulated by some theories of memory consolidation.

Dynamics of the hippocampal ensemble code for space.

Ensemble recordings of 73 to 148 rat hippocampal neurons were used to predict accurately the animals' movement through their environment, which confirms that the hippocampus transmits an ensemble code for location. In a novel space, the ensemble code was initially less robust but improved rapidly with exploration. During this period, the activity of many inhibitory cells was suppressed, which suggests that new spatial information creates conditions in the hippocampal circuitry that are conducive to the synaptic modification presumed to be involved in learning. Development of a new population code for a novel environment did not substantially alter the code for a familiar one, which suggests that the interference between the two spatial representations was very small. The parallel recording methods outlined here make possible the study of the dynamics of neuronal interactions during unique behavioral events.

Diurnal rhythm of cytoplasmic estrogen receptors in the rat brain in the absence of circulating estrogens.

The concentration of cytoplasmic estrogen receptors in the brain of ovariectomized female rats varies during the light-dark cycle. There is no variation in the affinity of the receptors for estradiol, and the rhythm is not due to estrogens from nonovarian sources. Pentobarbital reverses the reduction of receptors that occurs in the dark, and melatonin injection in the light partially mimics the action of darkness in reducing receptor levels. The factors that cause this rhythm is brain estrogen receptors may be one means by which light affects reproductive function.

Blind man living in normal society has circadian rhythms of 24.9 hours.

A psychologically normal blind man, living and working in normal society, suffered from a severe cyclic sleep-wake disorder. Investigations showed that he had circadian rhythms of body temperature, alertness, performance, cortisol secretion, and urinary electrolyte excretion which were desynchronized from the 24-hour societal schedule. These rhythms all had periods which were longer than 24 hours and indistinguishable from the period of the lunar day.

Comparative genomics of BCG vaccines by whole-genome DNA microarray.

Bacille Calmette-Guérin (BCG) vaccines are live attenuated strains of Mycobacterium bovis administered to prevent tuberculosis. To better understand the differences between M. tuberculosis, M. bovis, and the various BCG daughter strains, their genomic compositions were studied by performing comparative hybridization experiments on a DNA microarray. Regions deleted from BCG vaccines relative to the virulent M. tuberculosis H37Rv reference strain were confirmed by sequencing across the missing segment of the H37Rv genome. Eleven regions (encompassing 91 open reading frames) of H37Rv were found that were absent from one or more virulent strains of M. bovis. Five additional regions representing 38 open reading frames were present in M. bovis but absent from some or all BCG strains; this is evidence for the ongoing evolution of BCG strains since their original derivation. A precise understanding of the genetic differences between closely related Mycobacteria suggests rational approaches to the design of improved diagnostics and vaccines.

Vinegar (acetic acid) intake on glucose metabolism: A narrative review.

Vinegar intake is considered a food item that improves blood glucose in humans. This review aimed to discuss studies that investigated the impact of vinegar intake on the glycemic profile in humans and the putative mechanistic cellular pathways in both human and animal models. A search of literature was performed on the Cochrane, MEDLINE and Web of Science databases for articles published between 1995 and 2018. There is considerable support for vinegar having a positive acute effect on blood glucose levels when combined with carbohydrate-rich meals. Conversely, there are few chronic interventions analyzing the impact of vinegar intake on blood glucose. Based on available evidence, we hypothesize three pathways by which vinegar may improve blood glucose: The inhibition of α-amylase action; increased glucose uptake; and mediation by transcription factors. When evaluating the current body of literature, daily vinegar intake in amounts of ∼10-30 mL (∼2-6 tablespoons) appear to improve the glycemic response to carbohydrate-rich meals; however, there is a paucity of studies investigating chronic effects of vinegar intake.

Temporally structured replay of awake hippocampal ensemble activity during rapid eye movement sleep.

Human dreaming occurs during rapid eye movement (REM) sleep. To investigate the structure of neural activity during REM sleep, we simultaneously recorded the activity of multiple neurons in the rat hippocampus during both sleep and awake behavior. We show that temporally sequenced ensemble firing rate patterns reflecting tens of seconds to minutes of behavioral experience are reproduced during REM episodes at an equivalent timescale. Furthermore, within such REM episodes behavior-dependent modulation of the subcortically driven theta rhythm is also reproduced. These results demonstrate that long temporal sequences of patterned multineuronal activity suggestive of episodic memory traces are reactivated during REM sleep. Such reactivation may be important for memory processing and provides a basis for the electrophysiological examination of the content of dream states.

Coordinated interactions between hippocampal ripples and cortical spindles during slow-wave sleep.

Sleep is characterized by a structured combination of neuronal oscillations. In the hippocampus, slow-wave sleep (SWS) is marked by high-frequency network oscillations (approximately 200 Hz "ripples"), whereas neocortical SWS activity is organized into low-frequency delta (1-4 Hz) and spindle (7-14 Hz) oscillations. While these types of hippocampal and cortical oscillations have been studied extensively in isolation, the relationships between them remain unknown. Here, we demonstrate the existence of temporal correlations between hippocampal ripples and cortical spindles that are also reflected in the correlated activity of single neurons within these brain structures. Spindle-ripple episodes may thus constitute an important mechanism of cortico-hippocampal communication during sleep. This coactivation of hippocampal and neocortical pathways may be important for the process of memory consolidation, during which memories are gradually translated from short-term hippocampal to longer-term neocortical stores.

Experience-dependent asymmetric shape of hippocampal receptive fields.

We propose a novel parameter, namely, the skewness, or asymmetry, of the shape of a receptive field to characterize two properties of hippocampal place fields. First, a majority of hippocampal receptive fields on linear tracks are negatively skewed, such that during a single pass the firing rate is low as the rat enters the field but high as it exits. Second, while the place fields are symmetric at the beginning of a session, they become highly asymmetric with experience. Further experiments suggest that these results are likely to arise due to synaptic plasticity during behavior. Using a purely feed forward neural network model, we show that following repeated directional activation, NMDA-dependent long-term potentiation/long-term depotentiation (LTP/LTD) could result in an experience-dependent asymmetrization of receptive fields.