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Aims: Blood biomarkers can improve drug development for Alzheimer’s disease (AD) and its treatment. Neuron-derived extracellular vesicles (NDEVs) in plasma offer a minimally invasive platform for developing novel biomarkers that may be used to monitor the diverse pathogenic processes involved in AD. However, NDEVs comprise only a minor fraction of circulating extracellular vesicles (EVs). Most published studies have leveraged the L1 cell adhesion molecule (L1CAM) for NDEV immunocapture. We aimed to develop and optimize an alternative, highly specific immunoaffinity method to enrich blood NDEVs for biomarker development. Methods: After screening multiple neuronal antigens, we achieved NDEV capture with high affinity and specificity using antibodies against Growth-Associated Protein (GAP) 43 and Neuroligin 3 (NLGN3). The EV identity of the captured material was confirmed by electron microscopy, western blotting, and proteomics. The specificity for neuronal origin was demonstrated by showing enrichment for neuronal markers (proteins, mRNA) and recovery of spiked neuronal EVs. We performed NDEV isolation retrospectively from plasma samples from two cohorts of early AD patients (N = 19 and N = 40) and controls (N = 20 and N = 19) and measured p181-Tau, amyloid-beta (Aβ) 42, brain-derived neurotrophic factor (BDNF), precursor brain-derived neurotrophic factor (proBDNF), glutamate receptor 2 (GluR2), postsynaptic density protein (PSD) 95, GAP43, and syntaxin-1. Results: p181-Tau, Aβ42, and NRGN were elevated in AD samples, whereas proBDNF, GluR2, PSD95, GAP43, and Syntaxin-1 were reduced. Differences for p181-Tau, proBDNF, and GluR2 survived multiple-comparison correction and were correlated with cognitive scores. A model incorporating biomarkers correctly classified 94.7% of AD participants and 61.5% of control participants. The observed differences in NDEVs-associated biomarkers are consistent with previous findings. Conclusion: NDEV isolation by GAP43 and NLGN3 immunocapture offers a robust novel platform for biomarker development in AD, suitable for large-scale validation.

Aberrant neuronal translation is implicated in the etiology of numerous brain disorders. Although mTORC1-p70 ribosomal S6 kinase 1 (S6K1) signaling is critical for translational control, pharmacological manipulation in vivo has targeted exclusively mTORC1 due to the paucity of specific inhibitors to S6K1. However, small molecule inhibitors of S6K1 could potentially ameliorate pathological phenotypes of diseases, which are based on aberrant translation and protein expression. One such condition is fragile X syndrome (FXS), which is considered to be caused by exaggerated neuronal translation and is the most frequent heritable cause of autism spectrum disorder (ASD). To date, potential therapeutic interventions in FXS have focused largely on targets upstream of translational control to normalize FXS-related phenotypes. Here we test the ability of two S6K1 inhibitors, PF-4708671 and FS-115, to normalize translational homeostasis and other phenotypes exhibited by FXS model mice. We found that although the pharmacokinetic profiles of the two S6K1 inhibitors differed, they overlapped in reversing multiple disease-associated phenotypes in FXS model mice including exaggerated protein synthesis, inappropriate social behavior, behavioral inflexibility, altered dendritic spine morphology, and macroorchidism. In contrast, the two inhibitors differed in their ability to rescue stereotypic marble-burying behavior and weight gain. These findings provide an initial pharmacological characterization of the impact of S6K1 inhibitors in vivo for FXS, and have therapeutic implications for other neuropsychiatric conditions involving aberrant mTORC1-S6K1 signaling.

A gap exists between the expanding space of technological innovations to aid those affected by autism spectrum disorders, and the actual impact of those technologies on daily lives. This gap can be addressed through a very practical path of commercialization. However, the path from a technological innovation to a commercially viable product is fraught with challenges. These challenges can be mitigated through small business funding agencies, which are, more and more, catalyzing the dissemination of innovation by fostering social entrepreneurship through capital support and venture philanthropy. This letter describes the differences and nature of these agencies, and their importance in facilitating the translational and real-world impact of technological and scientific discoveries.

The central melanocortin (MC) system has been widely studied for its effects on food intake and sexual behavior. However, the MC system, and more specifically the MC4 receptor (MC4R), also interacts with neurochemical systems that regulate socioemotional behaviors, including oxytocin (OT) and dopamine. In monogamous prairie voles, OT and dopamine interact to promote partner preference formation, a laboratory measure of an enduring social bond between mates. Here we investigated the effects of MC receptor activation on partner preference formation in prairie voles, as well as the interaction between the MC and OT systems during this process. Peripheral administration of the brain penetrant MC3/4R receptor peptide agonist, Melanotan II (MTII), and the highly selective, small-molecule MC4R agonist, Pf-446687, enhanced partner preference formation in the prairie vole, but not in the non-monogamous meadow vole. MTII-induced partner preferences were enduring, as they were present 1 week after drug manipulation. The prosocial effects of MCR agonists may be mediated, in part, through modulation of OT, as coadministration of an OT receptor antagonist prevented MTII-induced partner preferences. MTII also selectively activated hypothalamic OT neurons and potentiated central OT release. As OT has been shown to enhance some aspects of social cognition in humans, our data suggest that the MC4R may be a viable therapeutic target for enhancing social function in psychiatric disorders, including autism spectrum disorders and schizophrenia, potentially through activation of the OT system.

A novel series of trans-1,3-cyclohexyl diamides was discovered and characterized as mGluR5 negative allosteric modulators (NAMs) lacking an alkyne moiety. Conformational constraint of one of the amide bonds in the diamide template led to a spirooxazoline template. A representative compound (24d) showed good in vitro potency, high CNS penetration and, upon subcutaneous dosing, demonstrated efficacy in the mouse marble burying test, generally used as indicative of potential anxiolytic activity.

Background Autism spectrum disorder (ASD) is a clinically and biologically heterogeneous condition characterized by social, repetitive, and sensory behavioral abnormalities. No treatments are approved for the core diagnostic symptoms of ASD. To enable the earliest stages of therapeutic discovery and development for ASD, robust and reproducible behavioral phenotypes and biological markers are essential to establish in preclinical animal models. The goal of this study was to identify electroencephalographic (EEG) and behavioral phenotypes that are replicable between independent cohorts in a mouse model of ASD. The larger goal of our strategy is to empower the preclinical biomedical ASD research field by generating robust and reproducible behavioral and physiological phenotypes in animal models of ASD, for the characterization of mechanistic underpinnings of ASD-relevant phenotypes, and to ensure reliability for the discovery of novel therapeutics. Genetic disruption of the SHANK3 gene, a scaffolding protein involved in the stability of the postsynaptic density in excitatory synapses, is thought to be responsible for a relatively large number of cases of ASD. Therefore, we have thoroughly characterized the robustness of ASD-relevant behavioral phenotypes in two cohorts, and for the first time quantified translational EEG activity in Shank3B null mutant mice. Methods In vivo physiology and behavioral assays were conducted in two independently bred and tested full cohorts of Shank3B null mutant (Shank3B KO) and wildtype littermate control (WT) mice. EEG was recorded via wireless implanted telemeters for 7 days of baseline followed by 20 min of recording following pentylenetetrazol (PTZ) challenge. Behaviors relevant to the diagnostic and associated symptoms of ASD were tested on a battery of established behavioral tests. Assays were designed to reproduce and expand on the original behavioral characterization of Shank3B KO mice. Two or more corroborative tests were conducted within each behavioral domain, including social, repetitive, cognitive, anxiety-related, sensory, and motor categories of assays. Results Relative to WT mice, Shank3B KO mice displayed a dramatic resistance to PTZ seizure induction and an enhancement of gamma band oscillatory EEG activity indicative of enhanced inhibitory tone. These findings replicated in two separate cohorts. Behaviorally, Shank3B KO mice exhibited repetitive grooming, deficits in aspects of reciprocal social interactions and vocalizations, and reduced open field activity, as well as variable deficits in sensory responses, anxiety-related behaviors, learning and memory. Conclusions Robust animal models and quantitative, replicable biomarkers of neural dysfunction are needed to decrease risk and enable successful drug discovery and development for ASD and other neurodevelopmental disorders. Complementary to the replicated behavioral phenotypes of the Shank3B mutant mouse is the new identification of a robust, translational in vivo neurophysiological phenotype. Our findings provide strong evidence for robustness and replicability of key translational phenotypes in Shank3B mutant mice and support the usefulness of this mouse model of ASD for therapeutic discovery.

The melanin-concentrating hormone 1 (MCH1) receptors play an important role in home-cage food consumption in rodents, but their role in operant high-fat food-reinforced responding or reinstatement of food seeking in animal models is unknown. Here, we used the MCH1 receptor antagonist SNAP 94847 to explore these questions.In experiment 1, we trained food-restricted rats (16 g/day of nutritionally balanced rodent diet) to lever press for high-fat (35%) pellets (3-h/day, every other day) for 14 sessions. We then tested the effect of SNAP 94847 (3-30 mg/kg, intraperitoneal (i.p.)) on food-reinforced operant responding. In experiments 2 and 3, we trained rats to lever press for the food pellets (9 to 14 3-h sessions) and subsequently extinguished the food-reinforced lever responding by removing the food (10 to 17 sessions). We then tested the effect of SNAP 94847 on reinstatement of food seeking induced by MCH (20 microg, intracerebroventricular), noncontingent delivery of three pellets during the first minute of the test session (pellet-priming), contingent tone-light cues previously associated with pellet delivery (cue), or the pharmacological stressor yohimbine (2 mg/kg, i.p.).Systemic injections of SNAP 94847 decreased food-reinforced operant responding and MCH-induced reinstatement of food seeking. SNAP 94847 had no effect on pellet-priming-, cue-, or yohimbine-induced reinstatement.Results indicate that MCH1 receptors are involved in food-reinforced operant responding but not in reinstatement induced by acute exposure to high-fat food, food cues, or the stress-like state induced by yohimbine. These results suggest that different mechanisms mediate food-reinforced operant responding and reinstatement of food seeking.

Melanin-concentrating hormone (MCH) is an orexigenic and dipsogenic neuropeptide that has been reported to mediate acute behavioral and neuroendocrine stress-related responses via MCH 1 receptor activation in rodents. The purpose of the present investigation was to use the MCH 1 receptor antagonist SNAP 94847 ( N -(3-{1-[4-(3,4-difluoro-phenoxy)-benzyl]-piperidin-4-yl}-4-methyl-phenyl)-isobutyramide) to determine the effects of MCH 1 receptor blockade on MCH-evoked adrenocorticotropic hormone (ACTH) release, chronic mild stress-induced anhedonia, stress-induced hyperthermia and forced swim stress-induced immobility. The appropriate dose range for testing SNAP 94847 was determined by measuring MCH-evoked water drinking. The corresponding occupancy of MCH 1 receptors in rat striatum was also measured across a broad dose range. Orally administered (p.o.) SNAP 94847 (1–10 mg/kg) corresponds to 30–60% occupancy at MCH 1 receptors and significantly blocks water drinking induced by the intracerebroventricular (i.c.v.) injection of MCH. MCH (i.c.v.) significantly elevates plasma levels of ACTH in rats, and SNAP 94847 (2.5 mg/kg, p.o.) blocks MCH-evoked ACTH release. Using the chronic mild stress paradigm, we show that repeated daily exposure to environmental stressors for 5 weeks significantly suppresses sucrose intake in rats, and that SNAP 94847 (1 mg/kg, BID) for 1–5 weeks restores baseline sucrose intake. Moreover, a single administration of SNAP 94847 attenuates stress-induced hyperthermia and the behavioral effects of forced swim stress with minimal effective doses of 2.5 and 30 mg/kg (p.o.), respectively. The regulation of ACTH release and reversal of the effects of chronic and acute stress by SNAP 94847 are suggestive of a role for MCH 1 receptor blockade in the treatment of disorders characterized by high allostatic load.

The melanin-concentrating hormone (MCH) system is anatomically and functionally interlaced with the mesocorticolimbic dopamine system. Therefore, we investigated whether MCH1 receptor knockout (KO) mice are more susceptible than wild-type (WT) mice to psychostimulant-induced locomotor stimulation and sensitization, dopamine receptor-mediated phosphorylation events and c-fos expression within the frontal cortex and ventral striatum. MCH1 receptor KO mice have 20% higher basal locomotor activity, are hypersensitive to the locomotor activating effects of d-amphetamine (1 mg/kg), and develop behavioral sensitization to a regimen of repeated d-amphetamine administration that does not induce sensitization in WT mice. In addition, d-amphetamine-mediated regulation of p44-mitogen activated protein kinase (MAPK) phosphorylation within the frontal cortex was significantly enhanced in MCH1 receptor KO mice, when compared with WT mice. No significant genotype difference in the effects of d-amphetamine on MAPK phosphorylation events within the ventral striatum, phosphorylation at Ser897 of the NR1 subunit of the NMDA receptor or Ca2+ and cyclic AMP response-element binding-protein (CREB) at Ser133 in the frontal cortex was detected. d-Amphetamine (3 mg/kg) increased c-fos expression within the frontal cortex in MCH1 receptor KO mice, but not WT mice. There were no d-amphetamine-induced changes in c-fos expression within the ventromedial striatum in KO or WT mice. Overall, MCH1 receptor KO mice are hypersensitive to the behavioral and molecular effects of the dopaminergic psychostimulant d-amphetamine. Increased frontal cortical MAPK phosphorylation and c-fos expression in MCH1 receptor KO mice indicates that the MCH1 receptor may be an important target for treating neuropsychiatric disorders characterized by frontal cortex dysfunction, including depression, attention deficit hyperactivity disorder (ADHD) and schizophrenia. Synapse 62:128–136, 2008. © 2007 Wiley-Liss, Inc.

The Nikon Metrology Laser Radar system focuses a beam from a fiber to a target object and receives the light scattered from the target through the same fiber. The system can, among other things, make highly accurate measurements of the position of a tooling ball by locating the angular position of peak signal quality, which is related to the fiber coupling efficiency. This article explores the relationship between fiber coupling efficiency and focus condition.

Psychogenic stress may be associated with the development of mood disorders and schizophrenia. The frontal cortex (FC) regulates stress responses, and its dysfunction contributes to certain neuropsychiatric disorders. We tested the effects of exposure to predator odor stress (POS), a psychogenic stressor, on the concurrent efflux of four major neurotransmitters within the FC in mice in comparison to immobilization stress (IMS), a physical/systemic stressor. POS and IMS significantly increased efflux of acetylcholine (ACh), serotonin (5-HT) and dopamine (DA), but not norephinephrine, within the FC. POS produced a somewhat longer-lasting efflux of 5-HT, as compared to IMS. The effects of POS and IMS on ACh, 5-HT and DA were blocked by chlordiazepoxide. Overall, we demonstrate a novel method to measure the effects of distinctly different stress modalities on FC neurotransmission and suggest that FC responsivity to stressors may be an important marker for evaluating anxiolytic drugs.

Melanin-concentrating hormone (MCH) neurons and MCH-1 receptors (MCH1r) densely populate mesolimbic dopaminergic brain regions such as the nucleus accumbens (NAc). The regulation of dopamine by MCH1r was suggested to be an important mechanism underlying the hyperactive phenotype of MCH1r knock-out (ko) mice. However, MCH1r modulation of monoamine neurotransmission has yet to be examined. We tested whether dopamine, norepinephrine, and serotonin function is dysregulated in MCH1r ko and wild-type (wt) mice. MCH1r ko mice exhibited robust hyperactivity in a novel or familiar environment and were super-sensitive to the locomotor activating effects ofd-amphetamine and the D1agonist 2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benazepine HCl. The D2agonist, quinpirole, decreased locomotion similarly in both ko and wt mice. Tissue contents of dopamine within the NAc and caudate-putamen were not significantly different in ko compared with wt mice. Basal and amphetamine-evoked NAc dopamine, norepinephrine, and serotonin efflux, as measured usingin vivomicrodialysis, were not significantly different between genotypes. In contrast, D1-like and D2-like receptor binding were significantly higher within the olfactory tubercle, ventral tegmental area, and NAc core and shell of ko mice. Norepinephrine transporter (NET) binding was significantly elevated within the NAc shell and globus pallidus of ko mice, whereas serotonin transporter binding was decreased in the NAc shell. Thus, deletion of MCH1r results in an upregulation of mesolimbic dopamine receptors and NET, indicating that MCH1r may negatively modulate mesolimbic monoamine function. MCH1r may be an important therapeutic target for neuropsychiatric disorders involving dysregulation of limbic monoamine systems.

The [ 14 C]-2-deoxyglucose ([ 14 C]-2-DG) quantitative autoradiographic technique was used to determine rates of local cerebral glucose utilization (LCGU) in discrete brain regions of adult, male alcohol-preferring (P) rats after 2 weeks of ethanol deprivation (E-D), 3 and 14 days of ethanol-relapse drinking (E-R3; E-R14), and in P rats, which were chronically drinking ethanol (E-C) for 8 weeks during daily 3-h scheduled-access sessions to 15% (vol./vol.) ethanol and water, or were ethanol-naive (E-N). The hypothesis to be tested was that ethanol-relapse drinking is initiated to restore changes in functional activity back to their chronic ethanol–exposed state. The LCGU rates were measured 1 h before the scheduled-access session. Mean ethanol intake did not differ among the groups. The LCGU rates were decreased in 41 of 57 regions or subregions examined in E-C rats compared with findings for E-N rats, including subregions of the cerebral cortex, hippocampus, and structures in the mesocorticolimbic and nigrostriatal systems. After 2 weeks of deprivation, LCGU values tended to return toward control values (E-N) in most CNS regions and did not differ significantly from control values in 12 regions or subregions (e.g., parts of the limbic system, cerebral cortex). Compared with LCGU values that recovered toward control levels in the E-D group, ethanol-relapse drinking was associated with decreased LCGU values in (1) 4 of 10 limbic structures, (2) all 6 cerebral cortical regions, (3) 1 of 4 basal ganglia regions, (4) 2 of 7 hippocampus subregions, and (5) 1 of 6 thalamic nuclei. The present results indicate that ethanol-relapse drinking was associated with reduced LCGU rates in most CNS regions that recovered toward control values and suggested to us that ethanol-relapse drinking may be initiated to restore neuronal function to its prior chronic ethanol–exposure state.

Illumination has been a critical factor to producing good imaging in microlithography since the beginning. Early lithographers used very simple illumination schemes, but as they improved their understanding of how the illumination influences image fidelity and resolution they moved into more complex partially coherent illumination conditions. Today, lithographers deploy many tricks with coherence and polarization that are tightly coupled with the patterns being imaged to help achieve seemingly impossible resolutions well below the classical definition. In this talk we review the progress of illumination engineering in microlithography up to the present.

Background: The present study compared baseline local cerebral glucose utilization (LCGU) values within reward-relevant brain regions in alcohol-naive, adult male high–alcohol-drinking (HAD) and low–alcohol-drinking (LAD) rats from replicate lines 1 and 2. Methods: 2-[14C]Deoxyglucose ([14C]2-DG) was injected (125 μCi/kg) intravenously during the rats’ dark cycle. Timed arterial blood samples were collected over 45 min and assayed for glucose as well as [14C]2-DG content. Rats were then decapitated; their brains quickly removed and frozen in isopentane at −50°C. Coronal sections from each brain were apposed to film and exposed for 2 days. Image densities were analyzed using quantitative autoradiography. Results: Data were collected from several key limbic (nucleus accumbens, ventral tegmental area, olfactory tubercle, amygdala, hippocampus, ventral pallidum, and septum), basal ganglia, cortical (medial prefrontal, frontal, parietal, temporal, occipital, entorhinal, pyriform, and cingulate), and subcortical (thalamus, habenula, and superior colliculus) structures. Because there were no significant differences between the replicates within each drinking line, data from the two replicates were combined to determine drinking line differences. When both replicate lines were combined, there were trends toward higher (approximately 15%) LCGU rates in HAD (n= 15) versus LAD (n= 16) rats within the parietal and occipital cortices, but neither of these line differences reached statistical significance (p < 0.01). Conclusions: The findings suggested that, within the HAD and LAD replicate rat lines, the selection for alcohol preference did not lead to differences in functional brain activity, as measured with the 2-DG method.

Objectives: Determining the source of human immunodeficiency virus 1 in the female genital tract and identifying factors that influence the amount of virus shed are important in the understanding of heterosexual human immunodeficiency virus 1 transmission. Study Design: Cervicovaginal human immunodeficiency virus 1 ribonucleic acid shedding was quantified before and after treatment of cervical squamous intraepithelial lesions in 14 women. Genotypic analysis was performed on peptide HIV-1 env gp120 of the major human immunodeficiency virus 1 species in plasma and cervicovaginal lavage of selected samples. Results: At 2 to 4 weeks after treatment, when cervices were inflamed and ulcerated, human immunodeficiency virus 1 ribonucleic acid in lavage samples increased 1.0 to 4.4 log 10. Genotypic analysis showed significant differences between the predominant human immunodeficiency virus 1 species in paired plasma and lavage samples from 2 of 4 women, suggesting that the increase in human immunodeficiency virus 1 was the result of local viral replication. Conclusions: Cervical inflammation and ulceration are associated with local human immunodeficiency virus 1 expression, which increases as much as 10,000-fold the amount of human immunodeficiency virus 1 shed into genital secretions. This may explain why sexually transmitted diseases are important risk factors for human immunodeficiency virus transmission. (Am J Obstet Gynecol 2001;184:279-85.)

This excerpt gives a succinct explanation of principle of linear superposition and complex notation.

This excerpt gives a succinct explanation of incoherent transfer function and the optical transfer function.

This excerpt gives a succinct explanation of Sommerfeld radiation and Kirchhoff boundary conditions.

This excerpt gives a succinct explanation of increasing versus decreasing phase convention.

This excerpt gives a succinct explanation of on-axis irradiance behind a circular aperture.

This excerpt gives a succinct explanation of the phase difference between parallel reflections.

This excerpt gives a succinct explanation of Poynting vector, irradiance, and optical admittance.

This excerpt gives a succinct explanation of the reflectance and transmittance of thin films.