293 research outputs found
A missense variant (P10L) of the melanopsin (OPN4) gene in seasonal affective disorder
Background: Melanopsin, a non-visual photopigment, may play a role in aberrant responses to low winter light levels in Seasonal Affective Disorder (SAD). We hypothesize that functional sequence variation in the melanopsin gene could contribute to increasing the light needed for normal functioning during winter in SAD. Methods: Associations between alleles, genotypes, and haplotypes of melanopsin in SAD participants (n = 130) were performed relative to controls with no history of psychopathology (n = 90). Results: SAD participants had a higher frequency of the homozygous minor genotype (T/T) for the missense variant rs2675703 (P10L) than controls, compared to the combined frequencies of C/C and C/T. Individuals with the T/T genotype were 5.6 times more likely to be in the SAD group than the control group, and all 7 (5%) of individuals with the T/T genotype at P10L were in the SAD group. Limitations: The study examined only one molecular component of the non-visual light input pathway, and recruitment methods for the comparison groups differed. Conclusion: These findings support the hypothesis that melanopsin variants may predispose some individuals to SAD. Characterizing the genetic basis for deficits in the non-visual light input pathway has the potential to define mechanisms underlying the pathological response to light in SAD, which may improve treatment. © 2008 Elsevier B.V
Ex vivo expansion of immature 4-hydroperoxycyclophosphamide-resistant progenitor cells from G-CSF-mobilized peripheral blood
AbstractThe application of ex vivo expansion to cell products pharmacologically purged in vitro may provide sufficient numbers of cells for rapid engraftment in a product with reduced tumor burden. To pursue this possibility we evaluated the effect of 4-hydroperoxycyclophosphamide (4-HC) treatment on granulocyte colony-stimulating factor-mobilized peripheral blood stem cells (G-PBSC) and their subsequent expansion potential. A small number of G-PBSC CD34+ cells are resistant to 4-HC and are phenotypically and functionally immature. 4-HC-resistant G-PBSC cells are CD34+ bright, CD38+/-, DR(lo), CD13(lo), CD33-, CD71-, and rhodamine dull. In six experiments, treating G-PBSC with 60 microg/mL of 4-HC at 37 degrees C for 30 minutes reduced the number of colony-forming units (CFUs) per 5000 CD34+ cells by 96.3% (from 1333 +/- 137 to 46.5 +/- 11). This purging also reduced the frequency of 5-week long-term culture initiating cells (LTC-ICs) from 1/39 (range 1/27 to 1/62) to <1/1680 (range 1/1180 to 1/2420). Ex vivo expansion cultures were used to compare the proliferative potential of treated and untreated CD34+ cells. These cells were cultured with either the HS-5 stromal cell line serum-deprived conditioned media supplemented with 10 ng/mL kit ligand (HS-5CM/KL) or a recombinant growth factor mix (GFmix) containing 10 ng/mL each of interleukin (IL)-1, IL-3, IL-6, KL, granulocyte colony-stimulating factor, granulocyte-macrophage colony-stimulating factor, and 3 U/mL of erythropoietin. Culturing untreated CD34+ G-PBSC with 10% HS-5CM/KL increased total nucleated cells by 460-fold after 15 days. Progenitors, which were measured as CFUs, also increased by 47-fold over the same period. More significantly, culturing the 4-HC-treated CD34+ cells with HS-5/KL increased CFUs 98-fold and the nucleated cells increased 4573-fold. The absolute number of CFUs present after expansion of the 4-HC-resistant cells with HS-5CM/KL was threefold higher than that detected before purging and significantly higher than that obtained with GFmix. These data indicate that G-PBSC contain a very immature pool of cells not detectable using the 5-week LTC-IC assay, but have extremely high proliferative potential. Additionally, pharmacological purging of G-PBSC greatly reduces mature cells while retaining an immature population. Also significant is the finding that supernatant from the HS-5 bone marrow stromal cell line plus KL can fully regenerate progenitors from the 4-HC-resistant CD34+ G-PBSC.Biol Blood Marrow Transplant 1998;4(2):61-8
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Proceedings of the Third International Workshop on the implementation of ALARA at nuclear power plants
This report contains the papers presented and the discussions that took place at the Third International Workshop on ALARA Implementation at Nuclear Power Plants, held in Hauppauge, Long Island, New York from May 8--11, 1994. The purpose of the workshop was to bring together scientists, engineers, health physicists, regulators, managers and other persons who are involved with occupational dose control and ALARA issues. The countries represented were: Canada, Finland, France, Germany, Japan, Korea, Mexico, the Netherlands, Spain, Sweden, the United Kingdom and the United States. The workshop was organized into twelve sessions and three panel discussions. Individual papers have been cataloged separately
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An RS Motif within the Epstein-Barr Virus BLRF2 Tegument Protein Is Phosphorylated by SRPK2 and Is Important for Viral Replication
Epstein-Barr virus (EBV) is a gammaherpesvirus that causes infectious mononucleosis, B cell lymphomas, and nasopharyngeal carcinoma. Many of the genes required for EBV virion morphogenesis are found in all herpesviruses, but some are specific to gammaherpesviruses. One of these gamma-specific genes, BLRF2, encodes a tegument protein that has been shown to be essential for replication in other gammaherpesviruses. In this study, we identify BLRF2 interacting proteins using binary and co-complex protein assays. Serine/Arginine-rich Protein Kinase 2 (SRPK2) was identified by both assays and was further shown to phosphorylate an RS motif in the BLRF2 C-terminus. Mutation of this RS motif (S148A+S150A) abrogated the ability of BLRF2 to support replication of a murine gammaherpesvirus 68 genome lacking the BLRF2 homolog (ORF52). We conclude that the BLRF2 RS motif is phosphorylated by SRPK2 and is important for viral replication
Replication of Bone Marrow Differentiation Niche: Comparative Evaluation of Different Three‐Dimensional Matrices
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97450/1/1008_ftp.pd
Genetic Risk Score Predicts Late-Life Cognitive Impairment
Introduction. A family history of Alzheimer's disease is a significant risk factor for its onset, but the genetic risk associated with possessing multiple risk alleles is still poorly understood. Methods. In a sample of 95 older adults (Mean age = 75.1, 64.2% female), we constructed a genetic risk score based on the accumulation of risk alleles in BDNF, COMT, and APOE. A neuropsychological evaluation and consensus determined cognitive status (44 nonimpaired, 51 impaired). Logistic regression was performed to determine whether the genetic risk score predicted cognitive impairment above and beyond that associated with each gene. Results. An increased genetic risk score was associated with a nearly 4-fold increased risk of cognitive impairment (OR = 3.824, P = .013) when including the individual gene polymorphisms as covariates in the model. Discussion. A risk score combining multiple genetic influences may be more useful in predicting late-life cognitive impairment than individual polymorphisms
Cognitive and behavioral predictors of light therapy use
Objective: Although light therapy is effective in the treatment of seasonal affective disorder (SAD) and other mood disorders, only 53-79% of individuals with SAD meet remission criteria after light therapy. Perhaps more importantly, only 12-41% of individuals with SAD continue to use the treatment even after a previous winter of successful treatment. Method: Participants completed surveys regarding (1) social, cognitive, and behavioral variables used to evaluate treatment adherence for other health-related issues, expectations and credibility of light therapy, (2) a depression symptoms scale, and (3) self-reported light therapy use. Results: Individuals age 18 or older responded (n = 40), all reporting having been diagnosed with a mood disorder for which light therapy is indicated. Social support and self-efficacy scores were predictive of light therapy use (p's<.05). Conclusion: The findings suggest that testing social support and self-efficacy in a diagnosed patient population may identify factors related to the decision to use light therapy. Treatments that impact social support and self-efficacy may improve treatment response to light therapy in SAD. © 2012 Roecklein et al
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