The propensity to exhibit social behaviors during interactions with same-sex and opposite-sex conspecifics is modulated by various neurotransmitters, including dopamine. Dopamine is a conserved ...neurotransmitter among vertebrates and dopaminergic receptors are also highly conserved among taxa. Activation of D1 and D2 dopamine receptor subtypes has been shown to modulate social behaviors, especially in mammalian and avian studies. However, the specific behavioral functions of these receptors vary across taxa. In reptiles there have been few studies examining the relationship between dopaminergic receptors and social behaviors. We therefore examined the effects of D1 and D2 agonists and antagonists on sexual and aggressive behaviors in the male green anole lizard (Anolis carolinensis). Treatment with high doses of both D1 and D2 agonists was found to impair both sexual and aggressive behaviors. However, the D1 agonist treatment was also found to impair motor function, suggesting that those effects were likely nonspecific. Lower doses of both agonists and antagonists failed to affect social behaviors. These findings provide some evidence for D2 receptor regulation of social behaviors, but in contrast with previous research, these effects are all inhibitory and no effects were found for manipulations of D1 receptors. A potential reason for the lack of more widespread effects on social behaviors using moderate or low drug doses is that systemic injection of drugs resulted in effects throughout the whole brain, thus affecting counteracting circuits which negated one another, making measurable changes in behavioral output difficult to detect. Future studies should administer drugs directly into brain regions known to regulate sexual and aggressive behaviors.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We present the final Sloan Digital Sky Survey IV (SDSS-IV) quasar catalog from Data Release 16 of the extended Baryon Oscillation Spectroscopic Survey (eBOSS). This catalog comprises the largest ...selection of spectroscopically confirmed quasars to date. The full catalog includes two subcatalogs (the current versions are DR16Q_v4 and DR16Q_Superset_v3 at https://data.sdss.org/sas/dr16/eboss/qso/DR16Q/): a "superset" of all SDSS-IV/eBOSS objects targeted as quasars containing 1,440,615 observations and a quasar-only catalog containing 750,414 quasars, including 225,082 new quasars appearing in an SDSS data release for the first time, as well as known quasars from SDSS-I/II/III. We present automated identification and redshift information for these quasars alongside data from visual inspections for 320,161 spectra. The quasar-only catalog is estimated to be 99.8% complete with 0.3%-1.3% contamination. Automated and visual inspection redshifts are supplemented by redshifts derived via principal component analysis and emission lines. We include emission-line redshifts for H , Hβ, Mg ii, C iii, C iv, and Ly . Identification and key characteristics generated by automated algorithms are presented for 99,856 broad absorption-line quasars and 35,686 damped Lyman alpha quasars. In addition to SDSS photometric data, we also present multiwavelength data for quasars from the Galaxy Evolution Explorer, UKIDSS, the Wide-field Infrared Survey Explorer, FIRST, ROSAT/2RXS, XMM-Newton, and Gaia. Calibrated digital optical spectra for these quasars can be obtained from the SDSS Science Archive Server.
We characterized polysubstance use burden and associations with mental health problems across demographic subgroups of PWH. In 2018-2020, as part of a primary care-based intervention study, PWH in ...care at three medical centers in Kaiser Permanente Northern California were screened for depression (PHQ-9≥10), anxiety (GAD-2≥3), and substance use (Tobacco, Alcohol, Prescription medication, and other Substance use TAPS≥1 per substance). We used Poisson regression to estimate prevalence ratios (PRs) comparing polysubstance use prevalence (TAPS≥1 for ≥2 substances) between PWH with positive screens for depression or anxiety vs. neither, among all PWH, and stratified by race/ethnicity and age (restricted to men), adjusting for sociodemographics, CD4, and HIV load. Screened PWH (N = 2865) included 92% men, 56% White, 19% Black, and 15% Hispanic PWH, with a median age of 55 years. Overall, polysubstance use prevalence was 26.4% (95% CI 24.9%-28.1%). PWH with depression or anxiety (n = 515) had an adjusted polysubstance use PR of 1.26 (1.09-1.46) vs. PWH with neither (n = 2350). Adjusted PRs were 1.47 (1.11-1.96), 1.07 (0.74-1.54), and 1.10 (0.85-1.41) among Black, Hispanic, and White men, respectively. Adjusted PRs did not differ by age group. Interventions should consider jointly addressing mental health and substance use problems and potential drivers, e.g. stigma or socioeconomic factors.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The recreational use of fentanyl in combination with xylazine (i.e., "tranq-dope") represents a rapidly emerging public health threat characterized by significant toxicity and mortality. This study ...quantified the interactions between these drugs on lethality and examined the effectiveness of potential rescue medications to prevent a lethal overdose.
Male and female mice were administered acute doses of fentanyl, xylazine, or their combination via intraperitoneal injection, and lethality was determined 0.5, 1.0, 1.5, 2.0, and 24 h after administration. Both fentanyl and xylazine produced dose-dependent increases in lethality when administered alone.
A nonlethal dose of fentanyl (56 mg/kg) produced an approximately 5-fold decrease in the estimated LD50 for xylazine (i.e., the dose estimated to produce lethality in 50% of the population). Notably, a nonlethal dose of xylazine (100 mg/kg) produced an approximately 100-fold decrease in the estimated LD
for fentanyl. Both drug combinations produced a synergistic interaction as determined via isobolographic analysis. The opioid receptor antagonist, naloxone (3 mg/kg), but not the alpha-2 adrenergic receptor antagonist, yohimbine (3 mg/kg), significantly decreased the lethality of a fentanyl-xylazine combination. Lethality was rapid, with death occurring within 10 min after a high dose combination and generally within 30 min at lower dose combinations. Males were more sensitive to the lethal effects of fentanyl-xylazine combinations under some conditions suggesting biologically relevant sex differences in sensitivity to fentanyl-xylazine lethality.
These data provide the first quantification of the lethal effects of "tranq-dope" and suggest that rapid administration of naloxone may be effective at preventing death following overdose.
Glioblastoma (GBM) is the most common and aggressive primary brain tumor resulting in high rates of morbidity and mortality. A strategy to increase the efficacy of available drugs and enhance the ...delivery of chemotherapeutics through the blood brain barrier (BBB) is desperately needed. We investigated the potential of Cisplatin conjugated gold nanoparticle (GNP-UP-Cis) in combination with MR-guided Focused Ultrasound (MRgFUS) to intensify GBM treatment. Viability assays demonstrated that GNP-UP-Cis greatly inhibits the growth of GBM cells compared to free cisplatin and shows marked synergy with radiation therapy. Additionally, increased DNA damage through γH2AX phosphorylation was observed in GNP-UP-Cis treated cells, along with enhanced platinum concentrations. In vivo, GNP-UP-Cis greatly reduced the growth of GBM tumors and MRgFUS led to increased BBB permeability and GNP-drug delivery in brain tissue.
Our studies suggest that GNP-Cis conjugates and MRgFUS can be used to focally enhance the delivery of targeted chemotherapeutics to brain tumors.
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Epidemiological studies report a high concordance rate of drug use within groups, suggesting an interplay between drug reinforcement and social cohesion. Preclinical studies reveal that (a) ...contingent access to a social partner increases cocaine intake and (b) experimenter-delivered cocaine increases the reinforcing effects of social contact. The purpose of this study was to determine if response-contingent cocaine increases the reinforcing effectiveness of social contact. Male rats were implanted with intravenous catheters and trained on a fixed ratio (FR1) schedule for 30-s access to a social partner. The reinforcing effectiveness of social contact was then determined using a progressive ratio (PR) schedule. After the PR test, rats were divided into two groups in which each response on an FR1 schedule produced social access and either response-contingent cocaine (0.5 mg/kg/infusion) or saline. After 9 days, the reinforcing effectiveness of social contact in the absence of infusions was determined again on the PR schedule. The cocaine and saline reinforcers were then switched between groups and the latter procedures were repeated. Recent exposure to response-contingent cocaine increased the reinforcing effectiveness of social contact on the PR schedule. This effect was transient, and the reinforcing effectiveness of social contact returned to baseline levels once response-contingent cocaine was replaced with saline. These data indicate that recent exposure to response-contingent cocaine transiently increases the reinforcing effectiveness of social contact and suggest that cocaine use may strengthen social cohesion by increasing the reinforcing effects of social contact with other individuals.
Public Health Significance
One of the most reliable predictors of drug use is whether an individual's peers use drugs. This study examined whether response-dependent cocaine increases the motivation for social contact. We report that response-dependent cocaine transiently increases the motivation for social contact, suggesting that cocaine use may increase social cohesion under some conditions.
Human induced pluripotent stem cell (hiPSC) technologies offer a unique resource for modeling neurological diseases. However, iPSC models are fraught with technical limitations including abnormal ...aggregation and inefficient maturation of differentiated neurons. These problems are in part due to the absence of synergistic cues of the native extracellular matrix (ECM). We report on the use of three artificial ECMs based on peptide amphiphile (PA) supramolecular nanofibers. All nanofibers display the laminin-derived IKVAV signal on their surface but differ in the nature of their non-bioactive domains. We find that nanofibers with greater intensity of internal supramolecular motion have enhanced bioactivity toward hiPSC-derived motor and cortical neurons. Proteomic, biochemical, and functional assays reveal that highly mobile PA scaffolds caused enhanced β1-integrin pathway activation, reduced aggregation, increased arborization, and matured electrophysiological activity of neurons. Our work highlights the importance of designing biomimetic ECMs to study the development, function, and dysfunction of human neurons.
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•ECM-mimetic PAs with distinct non-bioactive domains show different molecular motion•Culturing hiPSC-neurons on highly mobile IKVAV-PA2 nanofibers enhances ITGB1 activation•IKVAV-PA2 coatings reduce neuronal aggregation, increase functional maturity•IKVAV-PA2 coatings facilitate modeling of neurodegenerative pathology in vitro
The utilization of iPSC technologies to model neurological diseases in vitro is challenging due to the inherent tendency of neurons to aggregate and their immature profile. Kiskinis and colleagues developed artificial extracellular matrix biomimetic molecules exhibiting unprecedented molecular motion that promote advanced functional neuronal maturation and facilitate modeling of neurodegeneration.
Approximately 30% of elderly adults are cognitively unimpaired at time of death despite the presence of Alzheimer's disease neuropathology at autopsy. Studying individuals who are resilient to the ...cognitive consequences of Alzheimer's disease neuropathology may uncover novel therapeutic targets to treat Alzheimer's disease. It is well established that there are sex differences in response to Alzheimer's disease pathology, and growing evidence suggests that genetic factors may contribute to these differences. Taken together, we sought to elucidate sex-specific genetic drivers of resilience. We extended our recent large scale genomic analysis of resilience in which we harmonized cognitive data across four cohorts of cognitive ageing, in vivo amyloid PET across two cohorts, and autopsy measures of amyloid neuritic plaque burden across two cohorts. These data were leveraged to build robust, continuous resilience phenotypes. With these phenotypes, we performed sex-stratified n (males) = 2093, n (females) = 2931 and sex-interaction n (both sexes) = 5024 genome-wide association studies (GWAS), gene and pathway-based tests, and genetic correlation analyses to clarify the variants, genes and molecular pathways that relate to resilience in a sex-specific manner. Estimated among cognitively normal individuals of both sexes, resilience was 20-25% heritable, and when estimated in either sex among cognitively normal individuals, resilience was 15-44% heritable. In our GWAS, we identified a female-specific locus on chromosome 10 rs827389, β (females) = 0.08, P (females) = 5.76 × 10-09, β (males) = -0.01, P(males) = 0.70, β (interaction) = 0.09, P (interaction) = 1.01 × 10-04 in which the minor allele was associated with higher resilience scores among females. This locus is located within chromatin loops that interact with promoters of genes involved in RNA processing, including GATA3. Finally, our genetic correlation analyses revealed shared genetic architecture between resilience phenotypes and other complex traits, including a female-specific association with frontotemporal dementia and male-specific associations with heart rate variability traits. We also observed opposing associations between sexes for multiple sclerosis, such that more resilient females had a lower genetic susceptibility to multiple sclerosis, and more resilient males had a higher genetic susceptibility to multiple sclerosis. Overall, we identified sex differences in the genetic architecture of resilience, identified a female-specific resilience locus and highlighted numerous sex-specific molecular pathways that may underly resilience to Alzheimer's disease pathology. This study illustrates the need to conduct sex-aware genomic analyses to identify novel targets that are unidentified in sex-agnostic models. Our findings support the theory that the most successful treatment for an individual with Alzheimer's disease may be personalized based on their biological sex and genetic context.
We investigated relationships among immune, metabolic, and sleep abnormalities in mice with non-metastatic mammary cancer. Tumor-bearing mice displayed interleukin-6 (IL-6)-mediated peripheral ...inflammation, coincident with altered hepatic glucose processing and sleep. Tumor-bearing mice were hyperphagic, had reduced serum leptin concentrations, and enhanced sensitivity to exogenous ghrelin. We tested whether these phenotypes were driven by inflammation using neutralizing monoclonal antibodies against IL-6; despite the reduction in IL-6 signaling, metabolic and sleep abnormalities persisted. We next investigated neural populations coupling metabolism and sleep, and observed altered activity within lateral-hypothalamic hypocretin/orexin (HO) neurons. We used a dual HO-receptor antagonist to test whether increased HO signaling was causing metabolic abnormalities. This approach rescued metabolic abnormalities and enhanced sleep quality in tumor-bearing mice. Peripheral sympathetic denervation prevented tumor-induced increases in serum glucose. Our results link metabolic and sleep abnormalities via the HO system, and provide evidence that central neuromodulators contribute to tumor-induced changes in metabolism.
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•Tumors promote IL-6 driven inflammation and changes in metabolism and sleep•This is associated with aberrant activity of hypocretin/orexin (HO) neurons•Blocking HO signaling attenuated metabolic abnormalities and enhanced sleep quality•Reduced leptin and sensitivity to ghrelin may contribute to altered HO activity
Cancer patients with metabolic and sleep dysfunction have worse prognoses. Using a mouse model of breast cancer, Borniger, Walker II, et al. provide evidence that tumors deregulate satiety hormones, which likely alters the activity of hypocretin/orexin neurons. Aberrant activity in these cells impairs sleep and alters glucose metabolism via the sympathetic nervous system.
A return to cocaine use following abstinence frequently occurs in a social context, and the presence of other individuals using cocaine may contribute to the likelihood of use. Previous studies have ...reported that chronic d-amphetamine treatment decreases cocaine self-administration in laboratory animals and reduces a return to cocaine use following abstinence in humans.
The purpose of this study was to examine the effects of chronic d-amphetamine treatment on the reacquisition of cocaine use in rats self-administering cocaine in different social contexts.
Male and female rats were implanted with intravenous catheters and trained to self-administer cocaine during daily 6-hr sessions. After 14 days, cocaine self-administration was extinguished by substituting saline for the cocaine stimulus. At this time, rats were randomized to receive chronic treatment with either d-amphetamine or saline. After 9 days of extinction, cocaine was again made available during daily 6-hr sessions. At this time, rats were further randomized into three social conditions: (1) rats continued self-administering cocaine in isolation, (2) rats self-administered cocaine in the presence of a same-sex partner that also self-administered cocaine, or (3) rats self-administered cocaine in the presence of a same-sex partner that did not have access to cocaine. Daily treatment with d-amphetamine or saline continued for the duration of reacquisition testing.
Chronic treatment with d-amphetamine decreased cocaine intake during reacquisition, but these effects were not influenced by the social context. No sex differences were observed.
These data support previous studies reporting that d-amphetamine decreases cocaine intake and demonstrate its efficacy across social contexts.
•D-amphetamine and social context were examined on cocaine self-administration.•Cocaine self-administration was established prior to extinction and reacquisition.•Chronic d-amphetamine decreased the reacquisition of cocaine self-administration.•The effects of d-amphetamine were independent of social context.
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