1. |
- Abdo, A. A., et al.
(author)
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Gamma-ray emission concurrent with the nova in the symbiotic binary V407 cygni
- 2010
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In: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 329:5993, s. 817-821
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Journal article (peer-reviewed)abstract
- Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable γ-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce π0 decay γ-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.
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2. |
- Falchi, M., et al.
(author)
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Low copy number of the salivary amylase gene predisposes to obesity
- 2014
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In: Nature Genetics. - : Nature Publishing Group. - 1061-4036 .- 1546-1718. ; 46:5, s. 492-497
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Journal article (peer-reviewed)abstract
- Common multi-allelic copy number variants (CNVs) appear enriched for phenotypic associations compared to their biallelic counterparts. Here we investigated the influence of gene dosage effects on adiposity through a CNV association study of gene expression levels in adipose tissue. We identified significant association of a multi-allelic CNV encompassing the salivary amylase gene (AMY1) with body mass index (BMI) and obesity, and we replicated this finding in 6,200 subjects. Increased AMY1 copy number was positively associated with both amylase gene expression (P = 2.31 × 10-14) and serum enzyme levels (P < 2.20 × 10-16), whereas reduced AMY1 copy number was associated with increased BMI (change in BMI per estimated copy =-0.15 (0.02) kg/m 2; P = 6.93 × 10-10) and obesity risk (odds ratio (OR) per estimated copy = 1.19, 95% confidence interval (CI) = 1.13-1.26; P = 1.46 × 10-10). The OR value of 1.19 per copy of AMY1 translates into about an eightfold difference in risk of obesity between subjects in the top (copy number > 9) and bottom (copy number < 4) 10% of the copy number distribution. Our study provides a first genetic link between carbohydrate metabolism and BMI and demonstrates the power of integrated genomic approaches beyond genome-wide association studies. © 2014 Nature America, Inc. All rights reserved.
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3. |
- Hochberg, Z., et al.
(author)
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Child health, developmental plasticity, and epigenetic programming
- 2011
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In: Endocrine reviews. - : The Endocrine Society. - 0163-769X .- 1945-7189. ; 32:2, s. 159-224
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Research review (peer-reviewed)abstract
- Plasticity in developmental programming has evolved in order to provide the best chances of survival and reproductive success to the organism under changing environments. Environmental conditions that are experienced in early life can profoundly influence human biology and long-term health. Developmental origins of health and disease and life-history transitions are purported to use placental, nutritional, and endocrine cues for setting long-term biological, mental, and behavioral strategies in response to local ecological and/or social conditions. The window of developmental plasticity extends from preconception to early childhood and involves epigenetic responses to environmental changes, which exert their effects during life-history phase transitions. These epigenetic responses influence development, cell- and tissue-specific gene expression, and sexual dimorphism, and, in exceptional cases, could be transmitted transgenerationally. Translational epigenetic research in child health is a reiterative process that ranges from research in the basic sciences, preclinical research, and pediatric clinical research. Identifying the epigenetic consequences of fetal programming creates potential applications in clinical practice: the development of epigenetic biomarkers for early diagnosis of disease, the ability to identify susceptible individuals at risk for adult diseases, and the development of novel preventive and curative measures that are based on diet and/or novel epigenetic drugs.
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4. |
- Bolam, Kate A, et al.
(author)
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The relationship between BPAQ-derived physical activity and bone density of middle-aged and older men
- 2014
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In: Osteoporosis International. - : Springer Science and Business Media LLC. - 0937-941X .- 1433-2965. ; 25:11, s. 2663-2668
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Journal article (peer-reviewed)abstract
- The bone-specific physical activity questionnaire (BPAQ) accounts for activities that affect bone but has not been used in studies with older adults. Relationships exist between the BPAQ-derived physical activity and bone density in healthy middle-aged and older men but not men with prostate cancer. Disease-related treatments detrimental to bone should be considered when administering the BPAQ.INTRODUCTION:The bone-specific physical activity questionnaire (BPAQ) was developed to account for bone-specific loading. In this retrospective study, we examined the relationship between BPAQ-derived physical activity and bone mineral density (BMD) in middle-aged and older men with and without prostate cancer.METHODS:Two groups, 36 healthy men and 69 men with prostate cancer receiving androgen suppression therapy (AST), completed the BPAQ and had whole body, total hip, femoral (FN) and lumbar spine BMD assessed by dual-energy X-ray absorptiometry.RESULTS:Past (pBPAQ), current (cBPAQ) and total BPAQ (tBPAQ) scores for the healthy men were related to FN BMD (pBPAQ r = 0.36, p = 0.030; cBPAQ r s = 0.35, p = 0.034; tBPAQ r = 0.41, p = 0.014), and pBPAQ and tBPAQ were related to total hip (r s = 0.35, p = 0.035 and r s = 0.36, p = 0.029, respectively) and whole body BMD (r s = 0.44, p = 0.007 and r s = 0.45, p = 0.006, respectively). In men with prostate cancer, the BPAQ was not significantly associated with BMD. In stepwise regression analyses, body mass and tBPAQ predicted 30 % of the variance in total hip BMD (p = 0.003), cBPAQ predicted 14 % of the variance in FN BMD (p = 0.002), and body mass, age and tBPAQ predicted 47% of the variance in whole body BMD (p < 0.001) in healthy men. In men with prostate cancer, the BPAQ was not an independent predictor of BMD.CONCLUSIONS:Although BPAQ-derived estimates of physical activity are related to bone status in healthy middle-aged and older men, the adverse effect of AST on bone appears to obscure this relationship in men with prostate cancer.
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5. |
- Warren, Wesley C, et al.
(author)
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The genome of a songbird
- 2010
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 464:7289, s. 757-762
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Journal article (peer-reviewed)abstract
- The zebra finch is an important model organism in several fields with unique relevance to human neuroscience. Like other songbirds, the zebra finch communicates through learned vocalizations, an ability otherwise documented only in humans and a few other animals and lacking in the chicken-the only bird with a sequenced genome until now. Here we present a structural, functional and comparative analysis of the genome sequence of the zebra finch (Taeniopygia guttata), which is a songbird belonging to the large avian order Passeriformes. We find that the overall structures of the genomes are similar in zebra finch and chicken, but they differ in many intrachromosomal rearrangements, lineage-specific gene family expansions, the number of long-terminal-repeat-based retrotransposons, and mechanisms of sex chromosome dosage compensation. We show that song behaviour engages gene regulatory networks in the zebra finch brain, altering the expression of long non-coding RNAs, microRNAs, transcription factors and their targets. We also show evidence for rapid molecular evolution in the songbird lineage of genes that are regulated during song experience. These results indicate an active involvement of the genome in neural processes underlying vocal communication and identify potential genetic substrates for the evolution and regulation of this behaviour.
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6. |
- Baskin, Berivan, et al.
(author)
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TMEM43 mutations associated with arrhythmogenic right ventricular cardiomyopathy in non-Newfoundland populations
- 2013
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In: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 132:11, s. 1245-1252
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Journal article (peer-reviewed)abstract
- Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a myocardial disease characterized by fibro-fatty replacement of right ventricular free wall myocardium and life-threatening ventricular arrhythmias. A missense mutation, c.1073C>T (p.S358L) in the transmembrane protein 43 (TMEM43) gene, has been genetically identified to cause ARVC type 5 in a founder population from Newfoundland. It is unclear whether this mutation occurs in other populations outside of this founder population or if other variants of TMEM43 are associated with ARVC disease. We sought to identify non-Newfoundland individuals with TMEM43 variants among patient samples sent for genetic assessment for possible ARVC. Of 195 unrelated individuals with suspected ARVC, mutation of desmosomal proteins was seen in 28 and the p.S358L TMEM43 mutation in six. We identified a de novo p.S358L mutation in a non-Newfoundland patient and five separate rare TMEM43 (four novel) sequence variants in non-Newfoundland patients, each occurring in an evolutionarily conserved amino acid. TMEM43 mutations occur outside of the founder population of the island of Newfoundland where it was originally described. TMEM43 sequencing should be incorporated into clinical genetic testing for ARVC patients.
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7. |
- Berk, John L., et al.
(author)
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Repurposing Diflunisal for Familial Amyloid Polyneuropathy : A Randomized Clinical Trial
- 2013
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In: Journal of the American Medical Association (JAMA). - : American Medical Association (AMA). - 0098-7484 .- 1538-3598. ; 310:24, s. 2658-2667
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Journal article (peer-reviewed)abstract
- IMPORTANCE Familial amyloid polyneuropathy, a lethal genetic disease caused by aggregation of variant transthyretin, induces progressive peripheral nerve deficits and disability. Diflunisal, a nonsteroidal anti-inflammatory agent, stabilizes transthyretin tetramers and prevents amyloid fibril formation in vitro. OBJECTIVE To determine the effect of diflunisal on polyneuropathy progression in patients with familial amyloid polyneuropathy. DESIGN, SETTING, AND PARTICIPANTS International randomized, double-blind, placebo-controlled study conducted among 130 patients with familial amyloid polyneuropathy exhibiting clinically detectable peripheral or autonomic neuropathy at amyloid centers in Sweden (Umea), Italy (Pavia), Japan (Matsumoto and Kumamoto), England (London), and the United States (Boston, Massachusetts; New York, New York; and Rochester, Minnesota) from 2006 through 2012. INTERVENTION Participants were randomly assigned to receive diflunisal, 250 mg (n=64), or placebo (n=66) twice daily for 2 years. MAIN OUTCOMES AND MEASURES The primary end point, the difference in polyneuropathy progression between treatments, was measured by the Neuropathy Impairment Score plus 7 nerve tests (NIS+7) which ranges from 0 (no neurological deficits) to 270 points (no detectable peripheral nerve function). Secondary outcomes included a quality-of-life questionnaire (36-Item Short-Form Health Survey [SF-36]) and modified body mass index. Because of attrition, we used likelihood-based modeling and multiple imputation analysis of baseline to 2-year data. RESULTS By multiple imputation, the NIS+7 score increased by 25.0 (95% CI, 18.4-31.6) points in the placebo group and by 8.7 (95% CI, 3.3-14.1) points in the diflunisal group, a difference of 16.3 points (95% CI, 8.1-24.5 points; P < .001). Mean SF-36 physical scores decreased by 4.9 (95% CI, -7.6 to -2.2) points in the placebo group and increased by 1.5 (95% CI, -0.8 to 3.7) points in the diflunisal group (P < .001). Mean SF-36 mental scores declined by 1.1 (95% CI, -4.3 to 2.0) points in the placebo group while increasing by 3.7 (95% CI, 1.0-6.4) points in the diflunisal group (P = .02). By responder analysis, 29.7% of the diflunisal group and 9.4% of the placebo group exhibited neurological stability at 2 years (<2-point increase in NIS+7 score; P = .007). CONCLUSIONS AND RELEVANCE Among patients with familial amyloid polyneuropathy, the use of diflunisal compared with placebo for 2 years reduced the rate of progression of neurological impairment and preserved quality of life. Although longer-term follow-up studies are needed, these findings suggest benefit of this treatment for familial amyloid polyneuropathy.
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8. |
- Berk, John L, et al.
(author)
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The diflunisal trial : study accrual and drug tolerance
- 2012
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In: Amyloid. - : Informa UK Limited. - 1350-6129 .- 1744-2818. ; 19:S1, s. 37-38
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Journal article (peer-reviewed)abstract
- Familial amyloidotic polyneuropathy (FAP) is a protein folding disorder that induces neuropathy and cardiomyopathy, leading to death within 7-15 years after onset of clinical disease. In vitro, small ligands binding the thyroid hormone docking site stabilize tetrameric transthyretin, inhibiting amyloid fibril formation. We undertook a randomized, placebo-controlled clinical trial to determine whether diflunisal, a well-known non-steroidal anti-inflammatory drug (NSAID) alters neurologic disease progression in FAP. We enrolled 130 subjects with wide age and FAP mutation representation. To date, few recognized complications of NSAIDs have occurred in the study cohort. Data collection will be completed by November 2012.
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9. |
- Berk, J.L., et al.
(author)
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The diflunisal trial : update on study drug tolerance and disease progression
- 2011
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In: Amyloid : the international journal of experimental and clinical investigation : the official journal of the International Society of Amyloidosis. - : Informa UK Limited. - 1744-2818. ; 18:Suppl. 1, s. 191-192
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Journal article (peer-reviewed)abstract
- Abstract: Familial amyloidotic polyneuropathy (FAP) is a lethal genetic disorder that affects the peripheral and autonomic nervous systems, heart, gastro-intestinal (GI) tract, and soft tissues. Disease progression is increasingly reported following liver transplantation, the only proven treatment for FAP. Small molecule thyroxine mimetics stabilize transthyretin, inhibiting FAP amyloid fibril formation under stringent in vitro conditions. We report on the progress of an international, randomized placebo-controlled study designed to determine the effect of diflunisal, a thyroxine mimetic, on neurologic disease progression in patients with active FAP. Our experience to date indicates diflunisal is well tolerated by this study cohort and that neurologic disease advances more rapidly in FAP than it does in diabetes mellitus.Background: Transthyretin-related familial amyloidotic polyneuropathy (FAP) is a lethal autosomal dominant genetic disorder that predominantly affects the peripheral nervous system. FAP amyloid fibrils result from the misfolding of transthyretin, a transport protein predominantly produced by the liver. Although liver transplantation effectively treats patients with certain FAP mutations and limited disease, reports increasingly document progressive amyloid deposition following transplantation [1,2]. Alternative treatments are needed. In vitro investigations and a phase I clinical trial have demonstrated that thyroxine and small molecule mimetics, e.g. diflunisal, inhibit tetrameric transthyretin dissociation and suppress amyloid fibril formation [3,4].Methods: To examine the effect of diflunisal on disease progression in FAP, we designed a randomized, placebo controlled, double blind, multicenter international study employing the validated diabetic (DM) polyneuropathy metric, Neurologic Impairment Score + 7 attributes (NIS+7®), as the primary endpoint. A two-point change in NIS+7 correlates with clinically detectable progression of peripheral neuropathy among diabetics [5]. Entry criteria include proven FAP genotype, biopsy-proven amyloid deposits, and peripheral or autonomic neuropathy. Patients with alternate causes of neuropathy, other NSAID use, severe heart or kidney dysfunction, or previous liver transplantion are excluded. Study evaluations occur at entry, 6, 12, and 24 months. Adverse are collected by monthly telephone interviews, diary entries, and study site visit interactions. Relatedness of adverse events to study drug is assigned according to documentation in the investigational brochure, the protocol, the informed consent form; or at the investigator's discretion.Results: To date, 90 subjects have enrolled – 62 men and 28 women with median age 63 years (range 27–76 years). Adverse events tabulated by affected organ systems predominantly involved gastrointestinal events, more often attributed to disease complications than study drug side effects (Table 1). Although rare events, congestive heart failure in two subjects and GI bleeding in another prompted study drug discontinuation. Two disease-related deaths have occurred, both off study drug. Aggregate data from all study subjects (placebo and active drug arms) followed for at least 12 months identified a 3.2 point increase in median NIS+7 summated scores. In contrast, Dyck et al. [6] reported an annual 0.85 point increase in NIS+7 median scores in a large cohort of diabetics with polyneuropathy. Taken together, NIS+7 detected neurologic disease progression in this FAP cohort after 12 months observation. Additionally, NIS+7 measured disease advanced 3.5 times faster in our aggregate FAP study population than previously reported in DM.Conclusions: Diflunisal is well tolerated in FAP patients participating in the study. NIS+7, a composite scoring system, appears to be an effective study instrument for ATTR neuropathy, detecting significant change over 12 months observation. Neurologic disease progresses more rapidly in FAP than DM cohorts. The exact rate of disease progression in untreated FAP subjects detected by NIS+7 awaits unblinding of the data. These data will provide basis for future study design in FAP patients.
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10. |
- Kern, Jan, et al.
(author)
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Taking snapshots of photosynthetic water oxidation using femtosecond X-ray diffraction and spectroscopy
- 2014
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In: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 5, s. 4371-
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Journal article (peer-reviewed)abstract
- The dioxygen we breathe is formed by light-induced oxidation of water in photosystem II. O-2 formation takes place at a catalytic manganese cluster within milliseconds after the photosystem II reaction centre is excited by three single-turnover flashes. Here we present combined X-ray emission spectra and diffraction data of 2-flash (2F) and 3-flash (3F) photosystem II samples, and of a transient 3F' state (250 mu s after the third flash), collected under functional conditions using an X-ray free electron laser. The spectra show that the initial O-O bond formation, coupled to Mn reduction, does not yet occur within 250 mu s after the third flash. Diffraction data of all states studied exhibit an anomalous scattering signal from Mn but show no significant structural changes at the present resolution of 4.5 angstrom. This study represents the initial frames in a molecular movie of the structural changes during the catalytic reaction in photosystem II.
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