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Maxwell KN, Breslow JL
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Antibodies to PCSK9 A Superior Way to Lower LDL Cholesterol?

CIRCULATION RESEARCH 2012 JUL 20; 111(3):274-277
Hubel D, Wiesel T
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David Hubei and Torsten Wiesel

NEURON 2012 JUL 26; 75(2):182-184
While attending medical school at McGill, David Hubel developed an interest in the nervous system during the summers he spent at the Montreal Neurological Institute. After heading to the United States in 1954 for a Neurology year at Johns Hopkins, he was drafted by the army and was assigned to the Neuropsychiatry Division at the Walter Reed Hospital, where he began his career in research and did his first recordings from the visual cortex of sleeping and awake cats. In 1958, he moved to the lab of Stephen Kuffler at Johns Hopkins, where he began a long and fruitful collaboration with Torsten Wiesel. Born in Sweden, Torsten Wiesel began his scientific career at the Karolinska Institute, where he received his medical degree in 1954. After spending a year in Carl Gustaf Bernhard's laboratory doing basic neurophysiological research, he moved to the United States to be a postdoctoral fellow with Stephen Kuffler. It was at Johns Hopkins where he met David Hubel in 1958, and they began working together on exploring the receptive field properties of neurons in the visual cortex. Their collaboration continued until the late seventies. Hubel and Wiesel's work provided fundamental insight into information processing in the visual system and laid the foundation for the field of visual neuroscience. They have had many achievements, including-but not limited to-the discovery of orientation selectivity in visual cortex neurons and the characterization of the columnar organization of visual cortex through their discovery of orientation columns and ocular-dominance columns. Their work earned them the Nobel Prize for Physiology or Medicine in 1981, which they shared with Roger Sperry.
Nielsen DA, Ho A, Bahl A, Varma P, Kellogg S, Borg L, Kreek MJ
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Former heroin addicts with or without a history of cocaine dependence are more impulsive than controls

DRUG AND ALCOHOL DEPENDENCE 2012 JUL 1; 124(1-2):113-120
Background: Personality traits such as impulsivity and sensation seeking may contribute to the initiation and maintenance of illicit drug use. Since studies have reported higher impulsivity and sensation seeking traits in cocaine dependent subjects, we were interested in determining whether former heroin addicts in methadone pharmacotherapy with comorbid cocaine addiction have greater impulsivity than those without. Methods: Instruments to assess impulsivity (Barratt Impulsiveness Scale version 11) and sensation seeking (Sensation Seeking Scale version V) were administered to former severe heroin addicts meeting Federal criteria for methadone maintenance pharmacotherapy with (n = 71) or without cocaine dependence (n = 31) and to 145 normal healthy (non-methadone-maintained) volunteers. Results: The methadone-maintained without cocaine dependence and the methadone-maintained with cocaine dependence groups, both scored higher than did the normal volunteer group on the Barratt Impulsiveness Scale total score (p < 0.001). On the Barratt Impulsiveness Scale Attentional, Nonplanning, and Motor subscales, the methadone-maintained and methadone-maintained with cocaine dependence groups scored higher than did normal volunteers with no history of drug abuse or dependence (p < 0.001). There was no difference among groups on total score or any subscale of the Sensation Seeking Scale. However, males in all groups overall scored higher than did females on Disinhibition and Thrill and Adventure seeking subscales of the Sensation Seeking Scale version V (p < 0.001). Conclusions: This study demonstrates higher impulsivity in former severe heroin addicts meeting criteria for or currently in stable methadone maintenance pharmacotherapy, irrespective of a positive or negative history of cocaine dependence. (C) 2012 Elsevier Ireland Ltd. All rights reserved.
Johnson-Huang LM, Lowes MA, Krueger JG
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Putting together the psoriasis puzzle: an update on developing targeted therapies

DISEASE MODELS & MECHANISMS 2012 JUL; 5(4):423-433
Psoriasis vulgaris is a chronic, debilitating skin disease that affects millions of people worldwide. There is no mouse model that accurately reproduces all facets of the disease, but the accessibility of skin tissue from patients has facilitated the elucidation of many pathways involved in the pathogenesis of psoriasis and highlighted the importance of the immune system in the disease. The pathophysiological relevance of these findings has been supported by genetic studies that identified polymorphisms in genes associated with NF kappa B activation, IL-23 signaling and T helper 17 (Th17)-cell adaptive immune responses, and in genes associated with the epidermal barrier. Recently developed biologic agents that selectively target specific components of the immune system are highly effective for treating psoriasis. In particular, emerging therapeutics are focused on targeting the IL-23-Th17-cell axis, and several agents that block IL-17 signaling have shown promising results in early-phase clinical trials. This review discusses lessons learned about the pathogenesis of psoriasis from mouse- and patient-based studies, emphasizing how the outcomes of clinical trials with T-cell-targeted and cytokine-blocking therapies have clarified our understanding of the disease.
West AP, Diskin R, Nussenzweig MC, Bjorkman PJ
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Structural basis for germ-line gene usage of a potent class of antibodies targeting the CD4-binding site of HIV-1 gp120

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2012 JUL 24; 109(30):E2083-E2090
A large number of anti-HIV-1 antibodies targeting the CD4-binding site (CD4bs) on the envelope glycoprotein gp120 have recently been reported. These antibodies, typified by VRC01, are remarkable for both their breadth and their potency. Crystal structures have revealed a common mode of binding for several of these antibodies; however, the precise relationship among CD4bs antibodies remains to be defined. Here we analyze existing structural and sequence data, propose a set of signature features for potent VRC01-like (PVL) antibodies, and verify the importance of these features by mutagenesis. The signature features explain why PVL antibodies derive from a single germ-line human V-H gene segment and why certain gp120 sequences are associated with antibody resistance. Our results bear on vaccine development and structure-based design to improve the potency and breadth of anti-CD4bs antibodies.
Kawashima SA, Takemoto A, Nurse P, Kapoor TM
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Analyzing Fission Yeast Multidrug Resistance Mechanisms to Develop a Genetically Tractable Model System for Chemical Biology

CHEMISTRY & BIOLOGY 2012 JUL 27; 19(7):893-901
Chemical inhibitors can help analyze dynamic cellular processes, particularly when probes are active in genetically tractable model systems. Although fission yeast has served as an important model system, which shares more cellular processes (e.g., RNAi) with humans than budding yeast, its use for chemical biology has been limited by its multidrug resistance (MDR) response. Using genomics and genetics approaches, we identified the key transcription factors and drug-efflux transporters responsible for fission yeast MDR and designed strains sensitive to a wide-range of chemical inhibitors, including commonly used probes. We used this strain, along with acute chemical inhibition and high-resolution imaging, to examine metaphase spindle organization in a "closed" mitosis. Together, our findings suggest that our fission yeast strains will allow the use of several inhibitors as probes, discovery of new inhibitors, and analysis of drug action.
Tang AC, Reeb-Sutherland BC, Romeo RD, McEwen BS
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Reducing Behavioral Inhibition to Novelty via Systematic Neonatal Novelty Exposure: The Influence of Maternal Hypothalamic-Pituitary-Adrenal Regulation

BIOLOGICAL PSYCHIATRY 2012 JUL 15; 72(2):150-156
Background: Behavioral inhibition (BI) to novelty is thought to be a stable temperament type that appears early in life and is a major risk factor for anxiety disorders. In the rat, habituation of such inhibition can be facilitated via neonatal novelty exposure (NNE), thus reducing BI to novelty. Here, we tested the hypothesis that this early intervention effect is modulated by the context of maternal self-stress regulation. Methods: The NNE was carried out during postnatal days 1-21, in which one half of each litter was exposed to a relatively novel nonhome environment for 3-min daily while the remaining one half stayed in the home cage. After weaning, BI to novelty was assessed in an open field with a measure of disinhibition defined as a greater increase in exploration across two brief trials. Maternal context was characterized by trait measures of hypothalamic-pituitary-adrenal (HPA) axis reactivity, including basal and stress-evoked corticosterone (CORT) responses. Results: Family-to-family variations in the NNE effect were associated with variations in maternal HPA function-a low-basal CORT and high-evoked CORT response profile constituting the context for a novelty-induced facilitation of disinhibition (i.e., a greater increase in exploratory activity over repeated trials) and an opposite HPA profile constituting the context for a novelty-induced reduction of disinhibition. Conclusions: This result is consistent with the hypothesis that maternal self-stress regulation modulates the effect of early life intervention on BI to novelty and suggests that effective interventions should include strategies to help mothers improve their self-stress regulation.
Lu CP, Polak L, Rocha AS, Pasolli HA, Chen SC, Sharma N, Blanpain C, Fuchs E
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Identification of Stem Cell Populations in Sweat Glands and Ducts Reveals Roles in Homeostasis and Wound Repair

CELL 2012 JUL 6; 150(1):136-150
Sweat glands are abundant in the body and essential for thermoregulation. Like mammary glands, they originate from epidermal progenitors. However, they display few signs of cellular turnover, and whether they have stem cells and tissue-regenerative capacity remains largely unexplored. Using lineage tracing, we here identify in sweat ducts multipotent progenitors that transition to unipotency after developing the sweat gland. In characterizing four adult stem cell populations of glandular skin, we show that they display distinct regenerative capabilities and remain unipotent when healing epidermal, myoepithelial-specific, and lumenal-specific injuries. We devise purification schemes and isolate and transcriptionally profile progenitors. Exploiting molecular differences between sweat and mammary glands, we show that only some progenitors regain multipotency to produce de novo ductal and glandular structures, but that these can retain their identity even within certain foreign microenvironments. Our findings provide insight into glandular stem cells and a framework for the further study of sweat gland biology.
Langston LD, O'Donnell M
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Subunit sharing among high- and low-fidelity DNA polymerases

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2012 JUL 31; 109(31):12268-12269
Warner-Schmidt JL, Schmidt EF, Marshall JJ, Rubin AJ, Arango-Lievano M, Kaplitt MG, Ibanez-Tallon I, Heintz N, Greengard P
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Cholinergic interneurons in the nucleus accumbens regulate depression-like behavior

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2012 JUL 10; 109(28):11360-11365
A large number of studies have demonstrated that the nucleus accumbens (NAC) is a critical site in the neuronal circuits controlling reward responses, motivation, and mood, but the neuronal cell type(s) underlying these processes are not yet known. Identification of the neuronal cell types that regulate depression-like states will guide us in understanding the biological basis of mood and its regulation by diseases like major depressive disorder. Taking advantage of recent findings demonstrating that theserotonin receptor chaperone, p11, is an important molecular regulator of depression-like states, here we identify cholinergic interneurons (CINs) as a primary site of action for p11 in the NAC. Depression-like behavior is observed in mice after decrease of p11 levels in NAC CINs. This phenotype is recapitulated by silencing neuronal transmission in these cells, demonstrating that accumbal cholinergic neuronal activity regulates depression-like behaviors and suggesting that accumbal CIN activity is crucial for the regulation of mood and motivation.