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Recent observations indicate that >99% of the small bodies in the solar system reside in its outer reaches-in the Kuiper Belt and Oort Cloud. Kuiper Belt bodies are probably the best-preserved representatives of the icy planetesimals that dominated the bulk of the solid mass in the early solar system. They likely contain preserved materials inherited from the protosolar cloud, held in cryogenic storage since the formation of the solar system. Despite their importance, they are relatively underrepresented in our extraterrestrial sample collections by many orders of magnitude (~1013 by mass) as compared with the asteroids, represented by meteorites, which are composed of materials that have generally been strongly altered by thermal and aqueous processes. We have only begun to scratch the surface in understanding Kuiper Belt objects, but it is already clear that the very limited samples of them that we have in our laboratories hold the promise of dramatically expanding our understanding of the formation of the solar system. Stardust returned the first samples from a known small solar system body, the Jupiter-family comet 81P/Wild 2, and, in a separate collector, the first solid samples from the local interstellar medium. The first decade of Stardust research resulted in more than 142 peer-reviewed publications, including 15 papers in Science. Analyses of these amazing samples continue to yield unexpected discoveries and to raise new questions about the history of the early solar system. We identify nine high-priority scientific objectives for future Stardust analyses that address important unsolved problems in planetary science. [ABSTRACT FROM AUTHOR]

We studied the participation of GABA neurotransmission in the medial preoptic area ( mPOA) with respect to the onset of the pup retrieval response and nest building. Pregnant female rats were implanted with bilateral cannulae in the mPOA on day 12 of pregnancy and, on day 16, the females were hysterectomised and ovariectomised and given 200 μg/kg of oestradiol benzoate. Two days later, the females received one of the following intracerebral drug treatments: GABAB agonist baclofen (200 ng); GABAB antagonist phaclofen (1 μg); GABAA antagonist bicuculline (60 ng); or physiological saline. Five minutes after intracerebral infusion, three foster pups were introduced into the females' home cage. The subjects were observed for pup grouping (retrieval) during 15 min, after which the pups were left with the female. During the next 12 h, an observation was made every 1 h to determine whether the pups had been grouped (retrieved) or not. The GABAB agonist baclofen reduced the proportion of females retrieving pups from 4 to 8 h following pup introduction. By contrast, both the GABAA antagonist bicuculline and the GABAB antagonist phaclofen enhanced the proportion of females retrieving pups during the first 3 h of observation. The latency to pup retrieval in subjects treated with the GABAB agonist baclofen was significantly longer than that in subjects given any of the antagonists. All females built a nest but baclofen reduced nest quality. These data show that activation of GABAB receptors in the mPOA has an inhibitory effect on basic maternal behaviours, whereas blockade of either the GABAA or GABAB receptor facilitates pup retrieval. It is possible that reduced GABAergic tone in the mPOA is a key element in the initiation of maternal behaviours in postparturient rats. [ABSTRACT FROM AUTHOR]

Cocaine- and amphetamine-regulated transcript (CART) peptides are regulated neuropeptides that play a role in a variety of physiological processes. CART mRNA is also highly regulated as its levels change in response to psychostimulant drugs and leptin. To understand the mechanisms involved in regulating CART mRNA levels, the mouse CART 5′-flanking regulatory region was studied. The sequence of 3.4 kb of the mouse CART 5′-flanking region revealed a proximal promoter that contains a cluster of transcription factor binding sites, including an overlapping STAT/CRE/AP1 site. In addition, the 5′-most 320 bp of the CART promoter shares 83% nucleotide identity between mouse and human. Three luciferase expressing constructs containing varying amounts of CART 5′ upstream sequence were generated and tested for promoter activity. Transient transfection of GH3 cells with constructs containing 641 and 3451 bp of upstream sequence displayed strong promoter activity, producing 29-fold and 51-fold stimulation, respectively, while, a construct containing 102 bp of upstream sequence displayed a 5.4-fold increase in activity. A␣construct containing the composite STAT/CRE/AP1 site was responsive to cyclic AMP induction by forskolin in GH3 cells. Forskolin treatment also resulted in a 4.5-fold increase in CART mRNA levels after 6 h and the addition of H89, an inhibitor of protein kinase A, reduced the levels by 50%. These studies indicate that the CART proximal promoter lies within the 5′-most 641 bp and that in GH3 cells the CART gene is regulated via a cyclic AMP-dependent pathway. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate intergenerational breastfeeding practices according to parental sex and age at delivery in the 1993 Pelotas (Brazil) birth cohort study. This is a prospective birth cohort study, and at the 22-year follow-up, a substudy with all children of the cohort members who had become parents was conducted (93Cohort-II). First generation breastfeeding data were collected at 3 months and 4-year-old follow-ups. In the 93Cohort-II, parents answered a questionnaire about their children's breastfeeding practices. Adjusted Tobit and Poisson regression models with robust variance were applied to estimate the association between predominant parental breastfeeding duration and exclusive breastfeeding duration of the children at 3 and 6 months. Out of 3,810 cohort participants, 955 (25%) had delivered at least one live-born infant, and 1,222 children were assessed. Fifty-four percent of parents were ≤19 years old. Direct effects of predominant parental breastfeeding duration on exclusive breastfeeding duration of their children were only observed when data were stratified by parental age: children born to parents aged ≥20 years old and who were predominantly breastfed for at least 3 months presented higher exclusive breastfeeding duration and higher prevalence of being exclusively breastfed for at least 3 months. When analyses were stratified by mothers and fathers, the result remained significant only among mothers. Longer predominant breastfeeding duration in the first generation was associated with longer exclusive breastfeeding duration in the second generation, but only among older mothers. Education and social support surrounding breastfeeding should be intensified among fathers and younger parents to create a positive environment supportive of breastfeeding., (© 2020 The Authors. Maternal & Child Nutrition published by John Wiley & Sons, Ltd.)

This study intends to determine whether long-lasting glucocorticoids (GCs) dysregulation in the prefrontal cortex (PFC) or the dorsal hippocampus (dHPC) play a causal role in the maintenance of working memory (WM) deficits observed after alcohol withdrawal. Here, we report that C57/BL6 male mice submitted to 6 months alcohol consumption (12 percent v/v) followed by 1 (1W) or 6 weeks (6W) withdrawal periods exhibit WM deficits in a spatial alternation task and an exaggerated corticosterone rise during and after memory testing in the PFC but not the dHPC. In contrast, emotional reactivity evaluated in a plus-maze is altered only in the 1W group. No behavioral alterations are observed in mice still drinking alcohol. To determine the causal role of corticosterone in the withdrawal-associated long-lasting WM deficits, we further show that a single intraperitoneal injection injection of metyrapone (an inhibitor of corticosterone synthesis) 30 minutes before testing, prevents withdrawal-associated WM deficits and reestablishes PFC activity, as assessed by increased phosphorylated C-AMP Response Element-binding protein (CREB) immunoreactivity in withdrawn mice. Finally, we show that intra-PFC blockade of mineralocorticoid receptors by infusion of spironolactone and, to a lesser extent, of GCs receptors by injection of mifepristone reverses the WM deficits induced by withdrawal whereas the same injections into the dHPC do not. Overall, our study evidences that long-lasting GCs dysfunction selectively in the PFC is responsible for the emergence and maintenance of WM impairments after withdrawal and that blocking prefrontal mineralocorticoid receptors receptors restores WM in withdrawn animals., (© 2016 Society for the Study of Addiction.)