National Institutes of Health

About: National Institutes of Health is a government organization based out in Bethesda, Maryland, United States. It is known for research contribution in the topics: Population & Gene. The organization has 149298 authors who have published 297896 publications receiving 21337431 citations. The organization is also known as: NIH & U.S. National Institutes of Health.

A haplotype map of the human genome

Abstract: Inherited genetic variation has a critical but as yet largely uncharacterized role in human disease. Here we report a public database of common variation in the human genome: more than one million single nucleotide polymorphisms (SNPs) for which accurate and complete genotypes have been obtained in 269 DNA samples from four populations, including ten 500-kilobase regions in which essentially all information about common DNA variation has been extracted. These data document the generality of recombination hotspots, a block-like structure of linkage disequilibrium and low haplotype diversity, leading to substantial correlations of SNPs with many of their neighbours. We show how the HapMap resource can guide the design and analysis of genetic association studies, shed light on structural variation and recombination, and identify loci that may have been subject to natural selection during human evolution.

Validation of the five-factor model of personality across instruments and observers.

Abstract: Two data sources--self-reports and peer ratings--and two instruments--adjective factors and questionnaire scales--were used to assess the five-factor model of personality. As in a previous study of self-reports (McCrae & Costa, 1985b), adjective factors of neuroticism, extraversion, openness to experience, agreeableness-antagonism, and conscientiousness-undirectedness were identified in an analysis of 738 peer ratings of 275 adult subjects. Intraclass correlations among raters, ranging from .30 to .65, and correlations between mean peer ratings and self-reports, from .25 to .62, showed substantial cross-observer agreement on all five adjective factors. Similar results were seen in analyses of scales from the NEO Personality Inventory. Items from the adjective factors were used as guides in a discussion of the nature of the five factors. These data reinforce recent appeals for the adoption of the five-factor model in personality research and assessment.

Effectiveness of Antipsychotic Drugs in Patients with Chronic Schizophrenia

Abstract: background The relative effectiveness of second-generation (atypical) antipsychotic drugs as compared with that of older agents has been incompletely addressed, though newer agents are currently used far more commonly. We compared a first-generation antipsychotic, perphenazine, with several newer drugs in a double-blind study. methods A total of 1493 patients with schizophrenia were recruited at 57 U.S. sites and randomly assigned to receive olanzapine (7.5 to 30 mg per day), perphenazine (8 to 32 mg per day), quetiapine (200 to 800 mg per day), or risperidone (1.5 to 6.0 mg per day) for up to 18 months. Ziprasidone (40 to 160 mg per day) was included after its approval by the Food and Drug Administration. The primary aim was to delineate differences in the overall effectiveness of these five treatments. results Overall, 74 percent of patients discontinued the study medication before 18 months (1061 of the 1432 patients who received at least one dose): 64 percent of those assigned to olanzapine, 75 percent of those assigned to perphenazine, 82 percent of those assigned to quetiapine, 74 percent of those assigned to risperidone, and 79 percent of those assigned to ziprasidone. The time to the discontinuation of treatment for any cause was significantly longer in the olanzapine group than in the quetiapine (P<0.001) or risperidone (P=0.002) group, but not in the perphenazine (P=0.021) or ziprasidone (P=0.028) group. The times to discontinuation because of intolerable side effects were similar among the groups, but the rates differed (P=0.04); olanzapine was associated with more discontinuation for weight gain or metabolic effects, and perphenazine was associated with more discontinuation for extrapyramidal effects. conclusions The majority of patients in each group discontinued their assigned treatment owing to inefficacy or intolerable side effects or for other reasons. Olanzapine was the most effective in terms of the rates of discontinuation, and the efficacy of the conventional antipsychotic agent perphenazine appeared similar to that of quetiapine, risperidone, and ziprasidone. Olanzapine was associated with greater weight gain and increases in measures of glucose and lipid metabolism.

Regional studies of catecholamines in the rat brain. I. The disposition of [3H]norepinephrine, [3H]dopamine and [3H]dopa in various regions of the brain.

Abstract: NOREPINEPHRINE is found in appreciable amounts in mammalian brain tissue. VOGT (1954) showed that this amine was unequally distributed in various regions of the cat brain, the highest concentrations being found in the hypothalamus. Similar findings were reported for other animal species (BERTLER and ROSENGREN, 1959a; MCGEER, MCGEER and WADA, 1963) and man (SANO, GAMO, KAKIMOTO, TANAGUCHI, TAKE~ADA and NISHINUMA, 1959). Dopamine is also present in the brain in comparable amounts to norepinephrine (MONTAGU, 1957 ; CARLSSON, LINDQVIST, MAGNUSSON and WALDECK, 1958) but with a different regional distribution, the highest concentrations being in the corpus striatum of both animals and man (BERTLER and ROSENGREN, 1959a; SANO et al., 1959; EHRINGER and HORNYKIEWICZ, 1960; BERTLER, 1961). The anatomical distribution of these two catecholamines in the brain was confirmed by the use of fluorescent histochemical techniques which allow a precise description of the cellular localization of the amines in brain tissue (CARLSSON, FALK and HILLARP, 1962; DAHLSTROM and FUXE, 1964; FUXE, 1965). These techniques revealed that norepinephrine and dopamine are specifically localized in complex systems of neurons in the brain, a finding which lends support to the hypothesis that both amines may be neurotransmitters in the central nervous system. The metabolism of catecholamines in the rat brain was studied by introducing small amounts of radioactive norepinephrine or dopamine directly into the lateral ventricle (MILHAUD and GLOWINSKI, 1962, 1963; GLOWINSKI, KOPIN and AXELROD, 1965; GLOWINSKI, IVERSEN and AXELROD, 1966). By this approach the blood-brain barrier to catecholamines can be circumvented, penetration of the radioactive catecholamines into the brain being allowed. The disposition of PHInorepinephrine in the whole brain indicates that [3H]norepinephrine introduced into the lateral ventricle of the brain mixes with the endogenous amine and can be used as a tracer to study the biochemical behaviour of norepinephrine in the brain (GLOWINSKI and AXELROD, 1966). PHIDopamine, which is also taken up and retained in the brain, is rapidly metabolized and converted to norepinephrine (GLOWINSKI et a!., 1966). The unequal regional distribution of the endogeneous catecholamines in the brain led us to undertake a study of the disposition of radioactive norepinephrine and dopamine in various brain regions after intraventricular injection. The regional

The Endophenotype Concept in Psychiatry: Etymology and Strategic Intentions

Abstract: Endophenotypes, measurable components unseen by the unaided eye along the pathway between disease and distal genotype, have emerged as an important concept in the study of complex neuropsychiatric diseases. An endophenotype may be neurophysiological, biochemical, endocrinological, neuroanatomical, cognitive, or neuropsychological (including configured self-report data) in nature. Endophenotypes represent simpler clues to genetic underpinnings than the disease syndrome itself, promoting the view that psychiatric diagnoses can be decomposed or deconstructed, which can result in more straightforward-and successful-genetic analysis. However, to be most useful, endophenotypes for psychiatric disorders must meet certain criteria, including association with a candidate gene or gene region, heritability that is inferred from relative risk for the disorder in relatives, and disease association parameters. In addition to furthering genetic analysis, endophenotypes can clarify classification and diagnosis and foster the development of animal models. The authors discuss the etymology and strategy behind the use of endophenotypes in neuropsychiatric research and, more generally, in research on other diseases with complex genetics.