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Chronic social isolation (SI) stress, which became more prevalent during the COVID‐19 pandemic, contributes to abnormal behavior, including mood changes and cognitive impairment. Known as a functional nutrient, betaine has potent antioxidant and anti‐inflammatory properties in vivo. However, whether betaine can alleviate the abnormal behavior induced by chronic SI in mice remains unknown. In this study, we investigated the efficacy of betaine in the treatment of behavioral changes and its underlying mechanism. Three‐week‐old male mice were randomly housed for 8 weeks in either group housing (GH) or SI. The animals were divided into normal saline‐treated GH, normal saline‐treated SI, and betaine‐treated SI groups in the sixth week. The cognitive and depression‐like behavior was determined in the eighth week. We found that long‐term betaine administration improved cognitive behavior in SI mice but failed to prevent depression‐like behavior. Moreover, long‐term betaine administration inhibited hippocampal microglia over‐activation and polarized microglia toward the M2 phenotype, which effectively inhibited the expression of inflammatory factors in SI mice. Finally, the protective effect of betaine treatment in SI mice might not be due to altered activity of the hypothalamic–pituitary–adrenal axis. Collectively, our findings reveal that betaine can improve SI‐induced cognitive impairment, thus providing an alternative natural source for the prevention of memory loss caused by SI or loneliness. [ABSTRACT FROM AUTHOR]

Background: In highly complex social settings, an animal's motivational drive to pursue an object depends not only on the intrinsic properties of the object, but also on whether the decision-making animal perceives an object as being the most desirable among others. Mimetic desire refers to a subject's preference for objects already possessed by another subject. To date, there are no appropriate animal models for studying whether mimetic desire is at play in guiding the decision-making process. Furthermore, the neuropharmacological bases of decision-making processes are not well understood. In this study, we used an animal model (rat) to investigate a novel food-foraging paradigm for decision-making, with or without a mimetic desire paradigm.Results: Faced with the choice of foraging in a competitive environment, rats preferred foraging for the desirable object, indicating the rats' ability for decision-making. Notably, treatment with the non-competitive N-methyl-D-aspartate receptor antagonist MK-801, but not with the dopamine D1 or D2 receptor antagonists, SCH23390 and haloperidol, respectively, suppressed the food foraging preference when there was a competing resident rat in the cage. None of these three antagonists affected the food-foraging preference for palatable food. Moreover, MK-801 and SCH23390, but not haloperidol, were able to abolish the desirable environment effect on standard food-foraging activities in complex social settings.Conclusions: These results highlight the concept that mimetic desire exerts a powerful influence on food-foraging decision-making in rats and, further, illustrate the various roles of the glutamatergic and dopaminergic systems in mediating these processes. [ABSTRACT FROM AUTHOR]

Opioid addiction is a major social, economic, and medical problem worldwide. Long-term adverse consequences of chronic opiate exposure not only involve the individuals themselves but also their offspring. Adolescent maternal morphine exposure results in behavior and morphologic changes in the brain of their adult offspring. However, few studies investigate the effect of adult opiate exposure on their offspring. Furthermore, the underlying molecular signals regulating the intergenerational effects of morphine exposure are still elusive. We report here that morphine exposure of adult male and female rats resulted in anxiety-like behavior and dendritic retraction in the dentate gyrus (DG) region of the hippocampus in their adult offspring. The behavior and morphologic changes were concomitant with the downregulation of insulin-like growth factor (IGF)-2 signaling in the granular zone of DG. Overexpression of hippocampal IGF-2 by bilateral intra-DG injection of lentivirus encoding the IGF-2 gene prevented anxiety-like behaviors in the offspring. Furthermore, exposure to an enriched environment during adolescence corrected the reduction of hippocampal IGF-2 expression, normalized anxiety-like behavior and reversed dendritic retraction in the adult offspring. Thus, parental morphine exposure can lead to the downregulation of hippocampal IGF-2, which contributed to the anxiety and hippocampal dendritic retraction in their offspring. An adolescent-enriched environment experience prevented the behavior and morphologic changes in their offspring through hippocampal IGF-2 signaling. IGF-2 and an enriched environment may be a potential intervention to prevention of anxiety and brain atrophy in the offspring of parental opioid exposure. [ABSTRACT FROM AUTHOR]

Abstract: Previous studies have indicated involvement of the mitogen-activated protein kinase (MAPK) pathway in heterosexual interactions among rats. Very few studies, however, have focused its role in isosexual social interactions. We studied the male rat′s isosexual social interactional behavior using (i) the three-chambered social interaction box and (ii) phosphorylated extracellular signal-regulated kinase 1 and 2 (pERK1/2) to localize the brain regions that are activated during isosexual behavior. When faced with the social target side of the box versus the inanimate side, all rats preferred the social target side. Within 10min, isosexual social interactions induced a rapid increase in pERK1/2 expression in the brain, especially the main olfactory epithelial (MOE)-related brain regions. After ZnSO4-induced olfactory deprivation, rats showed no preference for either the social target or inanimate side, with a concomitant decrease in pERK1/2 expression in MOE-related brain regions. Additionally, to determine the role of pERK1/2 in isosexual social interactional behavior, rats were injected intraperitoneally with SL327 (30mg/kg, a MAPK kinase inhibitor). Although SL327 dramatically down-regulated expression of brain pERK1/2, experimental animals also spent significantly more time in the social target side. These results indicate that (i) A brief interacting with a male partner induced rapidly phosphorylated ERK1/2 in the rat′s brain. (ii) Destroy the function of MOE abolished the rats′ isosexual social interactional behavior. (iii) Suppressed the phosphorylated ERK1/2 in the rats′ brain disrupt their normal social behaviour. [Copyright &y& Elsevier]

The electroluminescence (EL) and photoluminescence (PL) spectra of InGaN/GaN multiple quantum wells (MQWs) with a prestrained InGaN interlayer in a laser diode structure are investigated. When the injection current increases from 5 mA to 50 mA, the blueshift of the EL emission peak is 1 meV for the prestrained sample and 23 meV for a control sample with the conventional structure. Also, the internal quantum efficiency and the EL intensity at the injection current of 20 mA are increased by 71% and 65% respectively by inserting the prestrained InGaN interlayer. The reduced blueshift and the enhanced emission are attributed mainly to the reduced quantum-confined Stark effect (QCSE) in the prestrained sample. Such attributions are supported by the theoretical simulation results, which reveal the smaller piezoelectric field and the enhanced overlap of electron and hole wave functions in the prestrained sample. Therefore, the prestrained InGaN interlayer contributes to strain relaxation in the MQW layer and enhancement of light emission due to the reduction of QCSE. [ABSTRACT FROM AUTHOR]

We investigate the mechanism for the improvement of p-type doping efficiency in Mg-Al0.14Ga0.86N/GaN superlattices (SLs). It is shown that the hole concentration of SLs increases by nearly an order of magnitude, from 1.1✕1017 to 9.3✕1017 cm-3, when an AlN interlayer is inserted to modulate the strains. Schrodinger-Poisson self-consistent calculations suggest that such an increase could be attributed to the reduction of donor-like defects caused by the strain modulation induced by the AlN interlayer. Additionally, the donor-acceptor pair emission exhibits a remarkable decrease in intensity of the cathodoluminescence spectrum for SLs with an AlN interlayer. This supports the theoretical calculations and indicates that the strain modulation of SLs could be beneficial to the donor-like defect suppression as well as the p-type doping efficiency improvement. [ABSTRACT FROM AUTHOR]

Introducing a thin InGaN interlayer with a relatively lower indium content between the quantum well (QW) and barrier results in a step-like InxGa1−xN/GaN potential barrier on one side of the QW. This change in the active region leads to a significant shift in photoluminescence (PL) and electroluminescence (EL) emissions to a longer wavelength compared with the conventional QW based light-emitting diodes. More importantly, an improvement against efficiency droop and an enhancement in light output power at the high-current injection are observed in the modified light-emitting diode structures. The role of the inserted layer in these improvements is investigated by simulation in detail, which shows that the creation of more sublevels in the valence band and the increase of hole concentration inside QWs are the main reasons for these improvements. [ABSTRACT FROM AUTHOR]

• Acute restrain stress changes food foraging behavior in both social or nonsocial settings. • Acute restrain stress affects the social-based more than value-based food foraging decision-making behavior. • Acute restrain stress enhances Social agonistic, but not social interaction behavior. • The neuronal activation of ACC caused by acute restrain stress could be the reason of inhibited food foraging. Stress can influence decision-making in humans from many cognitive perspectives, while the underlying neurobiological mechanism remains incompletely understood. Food-foraging is a rodent behavior involving strategic possessing of nutritional supply in social context; experimental model of this behavior could help explore the effect of stress on decision-making and the brain mechanism thereof. In the present study, the influence of stress on food-foraging behavior was assessed in rats using an open field choosing paradigm wherein food collection (standard food or sweet food) were associated with social competition (with or without a rat in the cage). Acute restraint stress (ARS) was induced by placing the rat in a plastic restrainer for 2 h before food-foraging behavioral tests, with the effect of stress also determined biochemically and immunohistochemically. Restraint stressed rats showed anxiety-like behavior and elevation of serum corticosterone (CORT) and epinephrine (EPI) relative to controls. Both restraint and control animals preferred sugared food. However, the former group tended to forage food from a cage not occupied by a conspecific rat, whereas the control rats preferred to obtain food from the cage with a social competitor. Thus, the total amount of food foraged and eaten are reduced in the restrained rats than in controls. While the restraint animals had normal social interaction with other rats, they displayed enhanced social agonistic behavior. In brain examination, ARS attenuated the increase in immunolabeling and protein levels of c-fos, p-CREB, p-ERK1/2 in the anterior cingulate cortex (ACC) observed in control animals in association with food-foraging. These results indicate that restraint stressed rats tend to forage food by taking the advantage of a less competitive opportunity. Mechanistically, this decision-making alternative appears to be mediated through a neuronal deactivation in the ACC. The current findings provide novel insights into neuronal processing of decision-making behavior under the influence of stress. [ABSTRACT FROM AUTHOR]

Background: Digital subtraction angiography (DSA), the gold standard for the diagnosis of intracranial arteriovenous malformations (AVMs), can show clean nidus resection, leading to a perceived cure. Most cases of intracranial AVM recurrence have been reported in pediatric patients. The conventional understanding indicates that AVMs arise when abnormal blood vessels develop between the fourth and eighth weeks of embryonic development, which coincides with the typical period of blood vessel formation in the brain. As such, recurrent ectopic AVM are rare in adults., Case Summary: Herein, we present the case of a 31-year-old adult with a history of an intracranial AVM originally diagnosed with a symptomatic de novo cerebellar AVM formation. Recurrence was observed five years following angiographically-confirmed excision of the initial AVM. DSA performed prior to initial AVM resection indicated no cerebellar abnormalities. Moreover, the recurrent arteries exhibited differences in arteries and draining veins. In addition to reporting this case, we analyzed six previously-reported adult patients with similar ectopic recurrent AVMs. These cases are summarized to review and explore the potential causes of ectopic AVM recurrence in adults, which increase the likelihood of acquired AVM., Conclusion: The clinical course of the reported patients demonstrated the possibility of ectopic AVM recurrence in adults. The median time between the diagnosis of the initial AVM and the occurrence of ectopic recurrent AVM in adults was 11 years (range: 5-20 years). Magnetic resonance imaging follow-up for more than 10 years may be required in adult AVM-treated patients., Competing Interests: Conflict-of-interest statement: All the authors declare that they have no competing interests., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: The rare co-occurrence of oligodendroglioma and arteriovenous malformation (AVM) in the same intracranial location., Case Summary: In a 61-year-old man presenting with progressive headaches, is described in this case study. Preoperative multimodal imaging techniques (computed tomography, magnetic resonance imaging, magnetic resonance spectroscopy, digital subtraction angiography, and computed tomography angiography) were employed to detect hemorrhage, cystic and solid lesions, and arteriovenous shunting in the right temporal lobe. The patient underwent right temporal craniotomy for lesion removal, and postoperative pathological analysis confirmed the presence of oligodendroglioma (World Health Organization grade II, not otherwise specified) and AVM., Conclusion: The preoperative utilization of multimodal imaging examination can help clinicians reduce the likelihood of misdiagnosis or oversight of these conditions, and provides important information for subsequent treatment. This case supports the feasibility of craniotomy for the removal of glioma with AVM., Competing Interests: Conflict-of-interest statement: The authors declare that they have no conflicts of interest concerning this article., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Background: In highly complex social settings, an animal's motivational drive to pursue an object depends not only on the intrinsic properties of the object, but also on whether the decision-making animal perceives an object as being the most desirable among others. Mimetic desire refers to a subject's preference for objects already possessed by another subject. To date, there are no appropriate animal models for studying whether mimetic desire is at play in guiding the decision-making process. Furthermore, the neuropharmacological bases of decision-making processes are not well understood. In this study, we used an animal model (rat) to investigate a novel food-foraging paradigm for decision-making, with or without a mimetic desire paradigm., Results: Faced with the choice of foraging in a competitive environment, rats preferred foraging for the desirable object, indicating the rats' ability for decision-making. Notably, treatment with the non-competitive N-methyl-D-aspartate receptor antagonist MK-801, but not with the dopamine D1 or D2 receptor antagonists, SCH23390 and haloperidol, respectively, suppressed the food foraging preference when there was a competing resident rat in the cage. None of these three antagonists affected the food-foraging preference for palatable food. Moreover, MK-801 and SCH23390, but not haloperidol, were able to abolish the desirable environment effect on standard food-foraging activities in complex social settings., Conclusions: These results highlight the concept that mimetic desire exerts a powerful influence on food-foraging decision-making in rats and, further, illustrate the various roles of the glutamatergic and dopaminergic systems in mediating these processes.