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Osteocytes' mechano-regulation of bone formation and resorption is key to maintaining appropriate bone health. Although extensive in vitro studies have explored osteocyte mechanobiology using the well-established MLO-Y4 cell model, the low amount of sclerostin secreted by this cell line renders it inadequate for studying cross-talk between osteocytes and osteoblasts under mechanical loading. Here, we investigated the potential of the sclerostin-expressing OCY454 osteocyte cell model in fulfilling this role. Fully differentiated OCY454 cells were tested for mechano-sensitivity by measuring changes in protein secretion, total adenosine triphosphate (ATP) content, and intracellular calcium in response to oscillatory fluid flow. Increases in sclerostin expression and total ATP content were observed. However, very low levels of receptor activator of the nuclear factor κ-B ligand were detected, and there was a great inconsistency in calcium response. Conditioned medium (CM) from OCY454 cells was then used to culture osteoblast and osteoclast precursors. Osteoblast activity was quantified with alkaline phosphatase (ALP) and Alizarin Red S stain, while osteoclast differentiation was quantified with tartrate-resistant acid phosphatase (TRAP) staining. We demonstrated that mechanically stimulated OCY454 cells released soluble factors that increased osteoblasts' ALP activity (p < 0.05) and calcium deposition (p < 0.05). There was also a significant decrease of large-sized TRAP-positive osteoclasts when osteoclast precursors were treated with CM from flow-stimulated OCY454 cells (p < 0.05). Results from this study suggest that OCY454 cells respond to mechanical loading with the release of key factors such as sclerostin to regulate downstream bone cells, thus demonstrating its potential as a novel cell model for in vitro osteocyte mechanobiology studies. [ABSTRACT FROM AUTHOR]

Abstract: The generation of the most abundant neurons of the cerebellum, the granule cells, relies on a balance between clonal expansion and apoptosis during the first 10days after birth in the external germinal layer (EGL). The amino acid glutamate controls such critical phases of cell development in other systems through specific receptors such as metabotropic glutamate receptor 5 (mGlu5R). However, the function of mGlu5Rs on the proliferation and survival of granule cell precursors (GCPs) remains elusive. We found mGlu5R mRNA transcripts in EGL using RT-PCR and observed mGlu5R-mediated Ca2+ responses in GCPs in acute slices as early as postnatal day (P) 2–3. Using in vivo injections of the selective non-competitive mGlu5R antagonist 2-methyl-6-(phenylethynyl)pyridine (MPEP) in P7–P9 mice, we found a 20% increase in the number of proliferative GCPs labeled at P7 with the S-phase marker bromodeoxyuridine (BrdU), but no increase in cell proliferation examined 2h following a BrdU injection. Furthermore, similar treatments led to a significant 70% decrease in the number of apoptotic GCPs in the EGL as determined by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. In contrast, in vivo treatment with the mGlu5R agonist (RS)-2-chloro-5-hydroxyphenylglycine (CHPG) resulted in a ∼60% increase in the number of TUNEL-labeled GCPs compared to control. These findings identify a unique role for glutamate acting at mGlu5Rs as a functional switch regulating GCP survival in the EGL, thus controlling the total number of cerebellar granule cells produced. [Copyright &y& Elsevier]

We investigated longitudinal relations between internalizing, externalizing, and total behaviors that challenge in young children on the autism spectrum and mothers' parenting stress. Participants included 93 mothers of children on the autism spectrum aged 27.89-65.84 months, who completed questionnaires on maternal parenting stress, and children's internalizing (anxiety), externalizing (disruptive), and total behaviors that challenge. Data were collected on early intervention program intake and approximately one year later. Cross-sectional findings indicated small to medium effect size associations between internalizing and externalizing behavior and parenting stress. However, cross-lagged structural equation models found that neither internalizing nor externalizing behavior predicted later parenting stress, nor the reverse. Significant stability effects were found for measures of child internalizing (anxiety), externalizing (disruptive), and total behaviors, and parenting stress. Relations between behaviors that challenge and parenting stress over time were non-significant in our models that controlled for stability of behaviors and parenting stress over time. Implications for research and clinical practice, in understanding and targeting the persistence of behaviors that challenge and parenting stress, are discussed., (© 2024. The Author(s).)

Introduction: As social animals, our health depends in part on interactions with other human beings. Yet millions suffer from chronic social isolation, including those in nursing/assisted living facilities, people experiencing chronic loneliness as well as those in enforced isolation within our criminal justice system. While many historical studies have examined the effects of early isolation on the brain, few have examined its effects when this condition begins in adulthood. Here, we developed a model of adult isolation using mice (C57BL/6J) born and raised in an enriched environment., Methods: From birth until 4 months of age C57BL/6J mice were raised in an enriched environment and then maintained in that environment or moved to social isolation for 1 or 3 months. We then examined neuronal structure and catecholamine and brain derived neurotrophic factor (BDNF) levels from different regions of the brain, comparing animals from social isolation to enriched environment controls., Results: We found significant changes in neuronal volume, dendritic length, neuronal complexity, and spine density that were dependent on brain region, sex, and duration of the isolation. Isolation also altered dopamine in the striatum and serotonin levels in the forebrain in a sex-dependent manner, and also reduced levels of BDNF in the motor cortex and hippocampus of male but not female mice., Conclusion: These studies show that isolation that begins in adulthood imparts a significant change on the homeostasis of brain structure and chemistry., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Heng, Zigmond and Smeyne.)

The neuropsychological symptoms associated with chemotherapy treatment remain a major challenge with their prevention hampered by insufficient understanding of pathophysiology. While long-term neuroimmune changes have been identified as a hallmark feature shared by neurological symptoms, the exact timeline of mechanistic events preceding neuroinflammation, and the relationship between the glial cells driving this neuroinflammatory response, remain unclear. We therefore aimed to longitudinally characterize the neuroimmunological changes following systemic 5-fluorouracil (5-FU) treatment to gain insight into the timeline of events preceding the well-documented chronic neuroinflammation seen following chemotherapy. Eighteen female C57Bl/6 mice received a single intraperitoneal dose of 5-FU and groups were killed at days 1 and 2 (acute timepoint), days 4 and 8 (subacute timepoint), and days 16 and 32 (chronic timepoint). A further six mice were administered with vehicle control with tissues collected from three mice on day 1 and day 32 of the study. The expression of key genes of interest, BCL2, BDNF, TIMP1, MMP-9, MMP-2, TNFα, IL-1β, and IL-6R were assessed using real time polymerase chain reaction. Levels of neurogenesis were determined through immunofluorescent staining of doublecortin (DCX). The density of microglia and astrocytes were assessed using immunofluorescence staining of Iba1 and GFAP respectively. 5-FU treatment caused significant decreases to DCX staining at acute timepoints (p = 0.0030) which was positively correlated with BCL2 expression levels. An increase to microglial density was observed in the prefrontal cortex (p = 0.0256), CA3 region (p = 0.0283), and dentate gyrus (p = 0.0052) of the hippocampus at acute timepoints. 5-FU caused increases to astrocyte density, across multiple brains regions, at subacute and chronic timepoints which were positively correlated with TNFα, TIMP-1, MMP-2, and IL-6R expression. This study has identified acute objective neuroinflammatory changes suggesting that the role of early intervention should be explored to prevent the development of neuropsychological deficits in the longer-term following chemotherapy., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: As interest in evaluating sex differences in nonhuman animals grows, the finding that male and female monkeys have toy preferences that differ, and that parallel those documented in human children, has garnered significant attention and is leveraged as an argument in favor of a biological contribution for human sex differences. To date, however, only two studies have investigated sex differences in monkeys' toy preferences, both documenting that males prefer toys considered to be "masculine" (such as vehicles) and females prefer toys considered to be "feminine" (such as dolls). Monkeys in these studies were tested in their social groups, making it hard to determine if the sex differences reported reflect actual individual preferences or result from social dynamics present at the time of testing., Method: Here, we assessed the preferences of 14 rhesus macaques (N = 7 males; N = 7 females) who were singly tested in a choice test with a variety of toys characterized as masculine (hard non-zoomorphic wheeled toys), feminine (zoomorphic soft toys), neutral (hard non-zoomorphic toys) and ambiguous (zoomorphic or plush vehicles) based on criteria from previous studies., Results: Males and females showed similar preferences for neutral and "masculine" toys and preferred them (i.e., were more likely to interact with them) to "feminine" and sex-ambiguous toys. When they interacted with the toys, both males and females interacted more with neutral than with "masculine" toys. Females, but not males, interacted more with neutral and "masculine" toys than with "feminine" toys. The highest frequency of interaction for any single toy for the male monkeys was with the doll-standing is stark contrast to previous findings., Conclusions: Our results contrast greatly with the previous study in rhesus monkeys, as well as findings in human children, suggesting that the previously documented sex differences are likely context dependent, and question the existence of a strong biological basis to sex differences in toy preferences., (© 2023. The Author(s).)

The "replication crisis" is a methodological problem in which many scientific research findings have been difficult or impossible to replicate. Because the reproducibility of empirical results is an essential aspect of the scientific method, such failures endanger the credibility of theories based on them and possibly significant portions of scientific knowledge. An instance of the replication crisis, analytic replication, pertains to reproducing published results through computational reanalysis of the authors' original data. However, direct replications are costly, time-consuming, and unrewarded in today's publishing standards. We propose that bioinformatics and computational biology students replicate recent discoveries as part of their curriculum. Considering the above, we performed a pilot study in one of the graduate-level courses we developed and taught at our University. The course is entitled Intro to R Programming and is meant for students in our Master's and PhD programs who have little to no programming skills. As the course emphasized real-world data analysis, we thought it would be an appropriate setting to carry out this study. The primary objective was to expose the students to real biological data analysis problems. These include locating and downloading the needed datasets, understanding any underlying conventions and annotations, understanding the analytical methods, and regenerating multiple graphs from their assigned article. The secondary goal was to determine whether the assigned articles contained sufficient information for a graduate-level student to replicate its figures. Overall, the students successfully reproduced 39% of the figures. The main obstacles were the need for more advanced programming skills and the incomplete documentation of the applied methods. Students were engaged, enthusiastic, and focused throughout the semester. We believe that this teaching approach will allow students to make fundamental scientific contributions under appropriate supervision. It will teach them about the scientific process, the importance of reporting standards, and the importance of openness., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Karathanasis et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The INTRABEAM system (Carl Zeiss Meditec AG, Jena, Germany) is an electronic brachytherapy (eBT) device designed for intraoperative radiotherapy applications. To date, the INTRABEAM x-ray source has not been characterized according to the AAPM TG-43 specifications for brachytherapy sources. This restricts its modelling in commercial treatment planning systems (TPSs), with the consequence that the doses to organs at risk are unknown. The aim of this work is to characterize the INTRABEAM source according to the TG-43 brachytherapy dosimetry protocol. The dose distribution in water around the source was determined with Monte Carlo (MC) calculations. For the validation of the MC model, depth dose calculations along the source longitudinal axis were compared with measurements using a soft x-ray ionization chamber (PTW 34013) and two synthetic diamond detectors (microDiamond PTW TN60019). In our results, the measurements in water agreed with the MC model calculations within uncertainties. The use of the microDiamond detector yielded better agreement with MC calculations, within estimated uncertainties, compared to the ionization chamber at points of steeper dose gradients. The radial dose function showed a steep fall-off close to the INTRABEAM source ([Formula: see text]10 mm) with a gradient higher than that of commonly used brachytherapy radionuclides ( 192 Ir, 125 I and 103 Pd), with values of 2.510, 1.645 and 1.232 at 4, 6 and 8 mm, respectively. The radial dose function partially flattens at larger distances with a fall-off comparable to that of the Xoft Axxent® (iCAD, Inc., Nashua, NH) eBT system. The simulated 2D polar anisotropy close to the bare probe walls showed deviations from unity of up to 55% at 10 mm and 155°. This work presents the MC calculated TG-43 parameters for the INTRABEAM, which constitute the necessary data for the characterization of the source as required by a TPS used in clinical dose calculations.

Introduction: Trajectory-based volumetric modulated arc therapy (tr-VMAT) treatment plans enable the option for noncoplanar delivery yielding steeper dose gradients and increased sparing of critical structures compared to conventional treatment plans. The addition of translational couch motion to shorten the effective source-to-axis distance (SAD) may result in improved delivery precision and an increased effective dose rate. In this work, tr-VMAT treatment plans using a noncoplanar "baseball stitch" trajectory were implemented, applied to patients presented with cranial targets, and compared to the clinical treatment plans., Methods: A treatment planning workflow was implemented: (a) beamlet doses were calculated for control points defined along a baseball stitch trajectory using a collapsed-cone convolution-superposition algorithm; (b) VMAT treatment plans were optimized using the column generation approach; (c) a final dose distribution was calculated in Varian Eclipse using the analytical anisotropic algorithm by importing the optimized treatment plan parameters. Tr-VMAT plans were optimized for ten patients presented with cranial targets at both standard and shortened SAD, and compared to the clinical treatment plans through isodose distributions, dose-volume histograms, and dosimetric indices. The control point specifications of the optimized tr-VMAT plans were used to estimate the delivery time., Results: The optimized tr-VMAT plans with both shortened and standard SAD delivery yielded a comparable plan quality to the clinical treatment plans. A statistically significant benefit was observed for dose gradient index and monitor unit efficiency for shortened SAD tr-VMAT plans, while improved target volume conformity was observed for the clinical treatment plan (P ≤ 0.05). A clear dosimetric benefit was not demonstrated between tr-VMAT delivery at shortened SAD compared to standard SAD, but shortened SAD delivery yielded a fraction size-dependent reduction in the estimated delivery time., Conclusion: The implementation of "baseball stitch" tr-VMAT treatment plans to patients presented with cranial targets demonstrated comparable plan quality to clinical treatment plans. The delivery at shortened SAD produced a fraction size-dependent decrease in estimated delivery time., (© 2020 American Association of Physicists in Medicine.)

Improved nature provision in urban environments offers great potential for achieving both biodiversity conservation and public health objectives. Yet there are few experimental studies that address links between specific natural environments and physiological and/or psychological changes that could contribute to the health and wellbeing co-benefits of urban nature. In addition, relative to green space, the salutogenic impact of aquatic environments are understudied. Here, we present a feasibility study examining the use of low-cost wearable technology to quantify the psychophysiological effects of short-term exposure to urban wetlands. The study took place at the WWT London Wetland Centre, which is characterized by its contrasting biodiverse wetland habitat and surrounding urban setting. Thirty-six healthy participants experienced counterbalanced exposures to an indoor space, a wetland, an urban site. We continuously recorded electroencephalographic (EEG) data and real-time physiological stress responses; with additional monitoring of post-exposure self-reported mood states. We found a significant effect of site on mean resting heart rate (HR), with increased HR in the urban setting, although this was only observed in participants with pre-existing high stress. We found no significant differences in other measures of physiological stress responses (heart rate variability and electrodermal activity). The EEG data showed modulation of high beta band activity only in the wetland setting, potentially related to changes in attention. However, the EEG findings were confounded by low quality signals and artifacts caused by movement and environmental interference. Assessments of self-reported mood states demonstrated an increase in positive feelings in the wetland setting. A pronounced decrease in negative feelings in the wetland setting was observed in stressed individuals only. Our results suggest that pre-existing stress levels may be an important modulator of the salutogenic effect of blue-green space. We provide partial support for the hypothesis that exposure to blue-green space promotes stress recovery and for the use of low-cost psychophysiological measurements to quantify the potential stress-reducing effects of blue-green space exposure in urban dwellers. Further technological refinement is required for this approach to become a viable tool to support evidence-based decision-making for public health and green/blue space provision.

The contribution of angiotensin II (Ang II) to the pathophysiology of hypertension is established based on facts that high levels of circulating Ang II increase vasoconstriction of peripheral arteries causing a rise in blood pressure (BP). In addition, circulating Ang II has various effects on the central nervous system, including the osmosensitive neurons in the organum vasculosum of the lamina terminalis (OVLT). Osmosensitive neurons in the OVLT transduce hypertonicity via the activation of the nonselective cation channel known as transient receptor potential vanilloid 1 (TRPV1), causing membrane depolarization, followed by increased action potential discharge. This effect is absent in mice lacking expression of the TRPV1 gene. Most observations related to the importance of the OVLT in cardiovascular control are mainly based on models of lesion of the entire preoptic periventricular tissue. However, it remains unclear whether neuronal activity and TRPV1 protein expression levels alter in the OVLT of Cyp1a1-Ren2 transgenic rats with inducible Ang II-dependent malignant hypertension. C-fos was used as a marker of neuronal activity. Immunostaining was used to demonstrate distribution of c-fos positive neurons in the OVLT of Cyp1a1Ren2 transgenic rats. Western blot analysis showed increased c-fos and TRPV1 total protein expression levels in the OVLT of hypertensive rats. The present findings demonstrate increased c-fos and TRPV1 expression levels in the OVLT of Cyp1a1-Ren2 transgenic rats with Ang II-dependent malignant hypertension., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)