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Li Y, Huang TT, Carlson EJ, Melov S, Ursell PC, Olson JL, Noble LJ, Yoshimura MP, Berger C, Chan PH, Wallace DC, Epstein CJ. Dilated cardiomyopathy and neonatal lethality in mutant mice lacking manganese superoxide dismutase. Nat Genet 1995; 11:376-81. [PMID: 7493016 DOI: 10.1038/ng1295-376] [Citation(s) in RCA: 1283] [Impact Index Per Article: 42.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The Sod2 gene for Mn-superoxide dismutase (MnSOD), an intramitochondrial free radical scavenging enzyme that is the first line of defense against superoxide produced as a byproduct of oxidative phosphorylation, was inactivated by homologous recombination. Homozygous mutant mice die within the first 10 days of life with a dilated cardiomyopathy, accumulation of lipid in liver and skeletal muscle, and metabolic acidosis. Cytochemical analysis revealed a severe reduction in succinate dehydrogenase (complex II) and aconitase (a TCA cycle enzyme) activities in the heart and, to a lesser extent, in other organs. These findings indicate that MnSOD is required for normal biological function of tissues by maintaining the integrity of mitochondrial enzymes susceptible to direct inactivation by superoxide.
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MESH Headings
- Acidosis/enzymology
- Animals
- Animals, Newborn
- Base Sequence
- Cardiomyopathy, Dilated/enzymology
- Cardiomyopathy, Dilated/genetics
- Electron Transport Complex IV/analysis
- Gene Targeting
- Genes, Lethal
- Homozygote
- Lipid Peroxidation
- Lipids/analysis
- Liver/chemistry
- Mice
- Mice, Mutant Strains
- Mitochondria, Heart/enzymology
- Mitochondria, Heart/ultrastructure
- Mitochondria, Muscle/enzymology
- Mitochondria, Muscle/ultrastructure
- Molecular Sequence Data
- Muscle, Skeletal/chemistry
- Sequence Deletion
- Succinate Dehydrogenase/analysis
- Superoxide Dismutase/genetics
- Superoxide Dismutase/metabolism
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1283 |
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Edelson R, Berger C, Gasparro F, Jegasothy B, Heald P, Wintroub B, Vonderheid E, Knobler R, Wolff K, Plewig G. Treatment of cutaneous T-cell lymphoma by extracorporeal photochemotherapy. Preliminary results. N Engl J Med 1987; 316:297-303. [PMID: 3543674 DOI: 10.1056/nejm198702053160603] [Citation(s) in RCA: 847] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Systemically disseminated cutaneous T-cell lymphoma is generally resistant to chemotherapy and radiotherapy. We tested a treatment involving the extracorporeal photoactivation of biologically inert methoxsalen (8-methoxypsoralen) by ultraviolet A energy to a form that covalently cross-links DNA. After oral administration of methoxsalen, a lymphocyte-enriched blood fraction was exposed to ultraviolet A (1 to 2 J per square centimeter) and then returned to the patient. The combination of ultraviolet A and methoxsalen caused an 88 +/- 5 percent loss of viability of target lymphocytes, whereas the drug alone was inactive. Twenty-seven of 37 patients with otherwise resistant cutaneous T-cell lymphoma responded to the treatment, with an average 64 percent decrease in cutaneous involvement after 22 +/- 10 weeks (mean +/- SD). The responding group included 8 of 10 patients with lymph-node involvement, 24 of 29 with exfoliative erythroderma, and 20 of 28 whose disease was resistant to standard chemotherapy. Side effects that often occur with standard chemotherapy, such as bone marrow suppression, gastrointestinal erosions, and hair loss, did not occur. Although the mechanism of the beneficial effect is uncertain, an immune reaction to the infused damaged cells may have restricted the activity of the abnormal T cells. This preliminary study suggests that extracorporeal photochemotherapy is a promising treatment for widespread cutaneous T-cell lymphoma.
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847 |
3
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Bevan M, Bancroft I, Bent E, Love K, Goodman H, Dean C, Bergkamp R, Dirkse W, Van Staveren M, Stiekema W, Drost L, Ridley P, Hudson SA, Patel K, Murphy G, Piffanelli P, Wedler H, Wedler E, Wambutt R, Weitzenegger T, Pohl TM, Terryn N, Gielen J, Villarroel R, De Clerck R, Van Montagu M, Lecharny A, Auborg S, Gy I, Kreis M, Lao N, Kavanagh T, Hempel S, Kotter P, Entian KD, Rieger M, Schaeffer M, Funk B, Mueller-Auer S, Silvey M, James R, Montfort A, Pons A, Puigdomenech P, Douka A, Voukelatou E, Milioni D, Hatzopoulos P, Piravandi E, Obermaier B, Hilbert H, Düsterhöft A, Moores T, Jones JD, Eneva T, Palme K, Benes V, Rechman S, Ansorge W, Cooke R, Berger C, Delseny M, Voet M, Volckaert G, Mewes HW, Klosterman S, Schueller C, Chalwatzis N. Analysis of 1.9 Mb of contiguous sequence from chromosome 4 of Arabidopsis thaliana. Nature 1998; 391:485-8. [PMID: 9461215 DOI: 10.1038/35140] [Citation(s) in RCA: 545] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The plant Arabidopsis thaliana (Arabidopsis) has become an important model species for the study of many aspects of plant biology. The relatively small size of the nuclear genome and the availability of extensive physical maps of the five chromosomes provide a feasible basis for initiating sequencing of the five chromosomes. The YAC (yeast artificial chromosome)-based physical map of chromosome 4 was used to construct a sequence-ready map of cosmid and BAC (bacterial artificial chromosome) clones covering a 1.9-megabase (Mb) contiguous region, and the sequence of this region is reported here. Analysis of the sequence revealed an average gene density of one gene every 4.8 kilobases (kb), and 54% of the predicted genes had significant similarity to known genes. Other interesting features were found, such as the sequence of a disease-resistance gene locus, the distribution of retroelements, the frequent occurrence of clustered gene families, and the sequence of several classes of genes not previously encountered in plants.
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545 |
4
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Glover TW, Berger C, Coyle J, Echo B. DNA polymerase alpha inhibition by aphidicolin induces gaps and breaks at common fragile sites in human chromosomes. Hum Genet 1984; 67:136-42. [PMID: 6430783 DOI: 10.1007/bf00272988] [Citation(s) in RCA: 476] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Aphidicolin, a specific inhibitor of DNA polymerase alpha, is known to induce chromosomal aberrations. At concentrations that did not greatly affect mitotic index, aphidicolin induced a striking number of chromosome gaps and breaks distributed in a highly nonrandom manner in cultured human lymphocytes. Specific chromosome bands, especially 2q31, 3p14, 6q26, 7q32, 16q23, and Xp22 were preferentially damaged in lymphocytes from each of 12 subjects studied. Total and site-specific damage was dose dependent and greatly increased when folic acid was removed from the medium. The sites most sensitive to aphidicolin damage include the "hot spots" seen under conditions of thymidylate stress and in studies of spontaneous chromosomal damage. The fragile X site, which can also be induced by thymidylate stress, was not induced by aphidicolin in lymphocytes, suggesting a separate mechanism for its induction. Aphidicolin represents a novel tool for detection of hot spots on human chromosomes through the mechanism of DNA polymerase alpha inhibition. The hot spots induced by aphidicolin represent a new class of fragile sites which we term common fragile sites.
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Berger C, Fiorelli M, Steiner T, Schäbitz WR, Bozzao L, Bluhmki E, Hacke W, von Kummer R. Hemorrhagic transformation of ischemic brain tissue: asymptomatic or symptomatic? Stroke 2001; 32:1330-5. [PMID: 11387495 DOI: 10.1161/01.str.32.6.1330] [Citation(s) in RCA: 357] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND AND PURPOSE The term symptomatic hemorrhage secondary to ischemic stroke implies a clear causal relationship between clinical deterioration and hemorrhagic transformation (HT) regardless of the type of HT. The aim of this study was to assess which type of HT independently affects clinical outcome. METHODS We used the data set of the European Cooperative Acute Stroke Study (ECASS) II for a post hoc analysis. All patients had a control CT scan after 24 to 96 hours or earlier in case of rapid and severe clinical deterioration. HT was categorized according to radiological criteria: hemorrhagic infarction type 1 and type 2 and parenchymal hematoma type 1 and type 2. The clinical course was prospectively documented with the National Institutes of Health Stroke Scale and the modified Rankin Scale: The independent risk of each type of HT was calculated for clinical deterioration at 24 hours and disability and death at 3 months after stroke onset and adjusted for possible confounding factors such as age, severity of stroke syndrome at baseline, and extent of the ischemic lesion on the initial CT. RESULTS Compared with absence of HT, only parenchymal hematoma type 2 was associated with an increased risk for deterioration at 24 hours after stroke onset (adjusted odds ratio, 18; 95% CI, 6 to 56) and for death at 3 months (adjusted odds ratio, 11; 95% CI, 3.7 to 36). All other types of HT did not independently increase the risk of late deterioration. CONCLUSIONS Only parenchymal hematoma type 2 independently causes clinical deterioration and impairs prognosis. It has a distinct radiological feature: it is a dense homogeneous hematoma >30% of the ischemic lesion volume with significant space-occupying effect.
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357 |
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Steiner M, Steinberg S, Stewart D, Carter D, Berger C, Reid R, Grover D, Streiner D. Fluoxetine in the treatment of premenstrual dysphoria. Canadian Fluoxetine/Premenstrual Dysphoria Collaborative Study Group. N Engl J Med 1995; 332:1529-34. [PMID: 7739706 DOI: 10.1056/nejm199506083322301] [Citation(s) in RCA: 275] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
BACKGROUND Premenstrual dysphoria shares certain features with depression and anxiety states, which have been linked to serotonergic dysregulation. We evaluated the efficacy and safety of fluoxetine (which selectively inhibits the reuptake of serotonin) in the treatment of premenstrual dysphoria. METHODS The trial consisted of a single-blind, placebo washout period lasting two menstrual cycles, followed by a randomized, double-blind, placebo-controlled trial of fluoxetine at a dose of either 20 mg or 60 mg per day or placebo for six menstrual cycles. Healthy women meeting criteria for what was then called late-luteal-phase dysphoric disorder were recruited at seven university-affiliated women's health clinics in Canada. The primary outcome measure consisted of visual-analogue scales for tension, irritability, and dysphoria during the late luteal phase of each cycle. RESULTS Of 405 women enrolled in the placebo washout period, 313 subsequently entered the randomized phase of the study, which lasted six menstrual cycles, and 180 completed it. Fluoxetine at a dose of 20 or 60 mg per day was significantly superior to placebo in reducing symptoms of tension, irritability, and dysphoria, as measured by the visual-analogue scales (P < 0.001). The women who received 60 mg of fluoxetine per day reported significantly more side effects than those who received 20 mg per day or placebo (P < 0.001). CONCLUSIONS Fluoxetine is useful in the treatment of premenstrual dysphoria. Treatment with fluoxetine at a dose of 20 mg per day reduces the potential for side effects while maximizing therapeutic efficacy.
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30 |
275 |
7
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Schäbitz WR, Berger C, Kollmar R, Seitz M, Tanay E, Kiessling M, Schwab S, Sommer C. Effect of Brain-Derived Neurotrophic Factor Treatment and Forced Arm Use on Functional Motor Recovery After Small Cortical Ischemia. Stroke 2004; 35:992-7. [PMID: 14988579 DOI: 10.1161/01.str.0000119754.85848.0d] [Citation(s) in RCA: 233] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Both the administration of growth factors and physical therapy such as forced arm use (FAU) are promising approaches to enhance recovery after stroke. We explored the effects of these therapies on behavioral recovery and molecular markers of regeneration after experimental ischemia. METHODS Rats were subjected to photothrombotic ischemia: sham (no ischemia), control (ischemia), brain-derived neurotrophic factor (BDNF; ischemia plus BDNF, 20 microg), and FAU (ischemia plus FAU, 1-sleeve plaster cast ipsilateral limb). Animals survived 1 or 6 weeks and underwent behavioral testing (Rotarod, beam balance, adhesive removal, plantar test, neuroscore). After the rats were killed, brain sections were immunostained for semiquantitative analysis of MAP1B, MAP2, synaptophysin, GFAP expression, and quantification of infarct volumes. RESULTS Infarct volumes were not different between the groups 1 or 6 weeks after ischemia. BDNF-treated animals had better functional motor recovery (Rotarod, beam balance, neuroscore) compared with all other groups (P<0.05). There was no significant adverse effect of early FAU treatment on motor recovery, although sensorimotor function (adhesive removal test) was impaired (P<0.05). There were no differences between groups as measured by nociception of the left and right forepaw (plantar test). BDNF treatment transiently induced MAP1B expression in the ischemic border zone and synaptophysin expression within the contralateral cortex 6 weeks after ischemia (P<0.05). Both BDNF and FAU reduced astrogliosis compared with controls (P<0.05). CONCLUSIONS Postischemic intravenous BDNF treatment improves functional motor recovery after photothrombotic stroke and induces widespread neuronal remodeling. Early FAU treatment after stroke does not increase infarct size, impairs sensorimotor function, but leaves motor function unchanged. Postischemic astrogliosis was reduced by both treatments.
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Mayer K, Schüller C, Wambutt R, Murphy G, Volckaert G, Pohl T, Düsterhöft A, Stiekema W, Entian KD, Terryn N, Harris B, Ansorge W, Brandt P, Grivell L, Rieger M, Weichselgartner M, de Simone V, Obermaier B, Mache R, Müller M, Kreis M, Delseny M, Puigdomenech P, Watson M, Schmidtheini T, Reichert B, Portatelle D, Perez-Alonso M, Boutry M, Bancroft I, Vos P, Hoheisel J, Zimmermann W, Wedler H, Ridley P, Langham SA, McCullagh B, Bilham L, Robben J, Van der Schueren J, Grymonprez B, Chuang YJ, Vandenbussche F, Braeken M, Weltjens I, Voet M, Bastiaens I, Aert R, Defoor E, Weitzenegger T, Bothe G, Ramsperger U, Hilbert H, Braun M, Holzer E, Brandt A, Peters S, van Staveren M, Dirske W, Mooijman P, Klein Lankhorst R, Rose M, Hauf J, Kötter P, Berneiser S, Hempel S, Feldpausch M, Lamberth S, Van den Daele H, De Keyser A, Buysshaert C, Gielen J, Villarroel R, De Clercq R, Van Montagu M, Rogers J, Cronin A, Quail M, Bray-Allen S, Clark L, Doggett J, Hall S, Kay M, Lennard N, McLay K, Mayes R, Pettett A, Rajandream MA, Lyne M, Benes V, Rechmann S, Borkova D, Blöcker H, Scharfe M, Grimm M, Löhnert TH, Dose S, de Haan M, Maarse A, Schäfer M, et alMayer K, Schüller C, Wambutt R, Murphy G, Volckaert G, Pohl T, Düsterhöft A, Stiekema W, Entian KD, Terryn N, Harris B, Ansorge W, Brandt P, Grivell L, Rieger M, Weichselgartner M, de Simone V, Obermaier B, Mache R, Müller M, Kreis M, Delseny M, Puigdomenech P, Watson M, Schmidtheini T, Reichert B, Portatelle D, Perez-Alonso M, Boutry M, Bancroft I, Vos P, Hoheisel J, Zimmermann W, Wedler H, Ridley P, Langham SA, McCullagh B, Bilham L, Robben J, Van der Schueren J, Grymonprez B, Chuang YJ, Vandenbussche F, Braeken M, Weltjens I, Voet M, Bastiaens I, Aert R, Defoor E, Weitzenegger T, Bothe G, Ramsperger U, Hilbert H, Braun M, Holzer E, Brandt A, Peters S, van Staveren M, Dirske W, Mooijman P, Klein Lankhorst R, Rose M, Hauf J, Kötter P, Berneiser S, Hempel S, Feldpausch M, Lamberth S, Van den Daele H, De Keyser A, Buysshaert C, Gielen J, Villarroel R, De Clercq R, Van Montagu M, Rogers J, Cronin A, Quail M, Bray-Allen S, Clark L, Doggett J, Hall S, Kay M, Lennard N, McLay K, Mayes R, Pettett A, Rajandream MA, Lyne M, Benes V, Rechmann S, Borkova D, Blöcker H, Scharfe M, Grimm M, Löhnert TH, Dose S, de Haan M, Maarse A, Schäfer M, Müller-Auer S, Gabel C, Fuchs M, Fartmann B, Granderath K, Dauner D, Herzl A, Neumann S, Argiriou A, Vitale D, Liguori R, Piravandi E, Massenet O, Quigley F, Clabauld G, Mündlein A, Felber R, Schnabl S, Hiller R, Schmidt W, Lecharny A, Aubourg S, Chefdor F, Cooke R, Berger C, Montfort A, Casacuberta E, Gibbons T, Weber N, Vandenbol M, Bargues M, Terol J, Torres A, Perez-Perez A, Purnelle B, Bent E, Johnson S, Tacon D, Jesse T, Heijnen L, Schwarz S, Scholler P, Heber S, Francs P, Bielke C, Frishman D, Haase D, Lemcke K, Mewes HW, Stocker S, Zaccaria P, Bevan M, Wilson RK, de la Bastide M, Habermann K, Parnell L, Dedhia N, Gnoj L, Schutz K, Huang E, Spiegel L, Sehkon M, Murray J, Sheet P, Cordes M, Abu-Threideh J, Stoneking T, Kalicki J, Graves T, Harmon G, Edwards J, Latreille P, Courtney L, Cloud J, Abbott A, Scott K, Johnson D, Minx P, Bentley D, Fulton B, Miller N, Greco T, Kemp K, Kramer J, Fulton L, Mardis E, Dante M, Pepin K, Hillier L, Nelson J, Spieth J, Ryan E, Andrews S, Geisel C, Layman D, Du H, Ali J, Berghoff A, Jones K, Drone K, Cotton M, Joshu C, Antonoiu B, Zidanic M, Strong C, Sun H, Lamar B, Yordan C, Ma P, Zhong J, Preston R, Vil D, Shekher M, Matero A, Shah R, Swaby IK, O'Shaughnessy A, Rodriguez M, Hoffmann J, Till S, Granat S, Shohdy N, Hasegawa A, Hameed A, Lodhi M, Johnson A, Chen E, Marra M, Martienssen R, McCombie WR. Sequence and analysis of chromosome 4 of the plant Arabidopsis thaliana. Nature 1999; 402:769-77. [PMID: 10617198 DOI: 10.1038/47134] [Show More Authors] [Citation(s) in RCA: 228] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The higher plant Arabidopsis thaliana (Arabidopsis) is an important model for identifying plant genes and determining their function. To assist biological investigations and to define chromosome structure, a coordinated effort to sequence the Arabidopsis genome was initiated in late 1996. Here we report one of the first milestones of this project, the sequence of chromosome 4. Analysis of 17.38 megabases of unique sequence, representing about 17% of the genome, reveals 3,744 protein coding genes, 81 transfer RNAs and numerous repeat elements. Heterochromatic regions surrounding the putative centromere, which has not yet been completely sequenced, are characterized by an increased frequency of a variety of repeats, new repeats, reduced recombination, lowered gene density and lowered gene expression. Roughly 60% of the predicted protein-coding genes have been functionally characterized on the basis of their homology to known genes. Many genes encode predicted proteins that are homologous to human and Caenorhabditis elegans proteins.
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Hass J, Varchon F, Millán-Otoya JE, Sprinkle M, Sharma N, de Heer WA, Berger C, First PN, Magaud L, Conrad EH. Why multilayer graphene on 4H-SiC(0001[over ]) behaves like a single sheet of graphene. PHYSICAL REVIEW LETTERS 2008; 100:125504. [PMID: 18517883 DOI: 10.1103/physrevlett.100.125504] [Citation(s) in RCA: 216] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2007] [Indexed: 05/13/2023]
Abstract
We show experimentally that multilayer graphene grown on the carbon terminated SiC(0001[over ]) surface contains rotational stacking faults related to the epitaxial condition at the graphene-SiC interface. Via first-principles calculation, we demonstrate that such faults produce an electronic structure indistinguishable from an isolated single graphene sheet in the vicinity of the Dirac point. This explains prior experimental results that showed single-layer electronic properties, even for epitaxial graphene films tens of layers thick.
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Tenenhouse A, Joseph L, Kreiger N, Poliquin S, Murray TM, Blondeau L, Berger C, Hanley DA, Prior JC. Estimation of the prevalence of low bone density in Canadian women and men using a population-specific DXA reference standard: the Canadian Multicentre Osteoporosis Study (CaMos). Osteoporos Int 2000; 11:897-904. [PMID: 11199195 DOI: 10.1007/s001980070050] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The Canadian Multicentre Osteoporosis Study (CaMos) is a prospective cohort study which will measure the incidence and prevalence of osteoporosis and fractures, and the effect of putative risk factors, in a random sample of 10,061 women and men aged > or = 25 years recruited in approximately equal numbers in nine centers across Canada. In this paper we report the results of studies to establish peak bone mass (PBM) which would be appropriate reference data for use in Canada. These reference data are used to estimate the prevalence of osteoporosis and osteopenia in Canadian women and men aged > or = 50 years. Participants were recruited via randomly selected household telephone listings. Bone mineral density (BMD) of the lumbar spine and femoral neck were measured by dual-energy X-ray absorptiometry using Hologic QDR 1000 or 2000 or Lunar DPX densitometers. BMD results for lumbar spine and femoral neck were converted to a Hologic base. BMD of the lumbar spine in 578 women and 467 men was constant to age 39 years giving a PBM of 1.042 +/- 0.121 g/cm2 for women and 1.058 +/- 0.127 g/cm2 for men. BMD at the femoral neck declined from age 29 years. The mean femoral neck BMD between 25 and 29 years was taken as PBM and was found to be 0.857 +/- 0.125 g/cm2 for women and 0.910 +/- 0.125 g/cm2 for men. Prevalence of osteoporosis, as defined by WHO criteria, in Canadian women aged > or = 50 years was 12.1% at the lumbar spine and 7.9% at the femoral neck with a combined prevalence of 15.8%. In men it was 2.9% at the lumbar spine and 4.8% at the femoral neck with a combined prevalence of 6.6%.
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199 |
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Varchon F, Feng R, Hass J, Li X, Nguyen BN, Naud C, Mallet P, Veuillen JY, Berger C, Conrad EH, Magaud L. Electronic structure of epitaxial graphene layers on SiC: effect of the substrate. PHYSICAL REVIEW LETTERS 2007; 99:126805. [PMID: 17930540 DOI: 10.1103/physrevlett.99.126805] [Citation(s) in RCA: 190] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2006] [Indexed: 05/14/2023]
Abstract
A strong substrate-graphite bond is found in the first all-carbon layer by density functional theory calculations and x-ray diffraction for few graphene layers grown epitaxially on SiC. This first layer is devoid of graphene electronic properties and acts as a buffer layer. The graphene nature of the film is recovered by the second carbon layer grown on both the (0001) and (0001[over]) 4H-SiC surfaces. We also present evidence of a charge transfer that depends on the interface geometry. Hence the graphene is doped and a gap opens at the Dirac point after three Bernal stacked carbon layers are formed.
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Heald P, Rook A, Perez M, Wintroub B, Knobler R, Jegasothy B, Gasparro F, Berger C, Edelson R. Treatment of erythrodermic cutaneous T-cell lymphoma with extracorporeal photochemotherapy. J Am Acad Dermatol 1992; 27:427-33. [PMID: 1401279 DOI: 10.1016/0190-9622(92)70212-x] [Citation(s) in RCA: 186] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND This original cohort of patients with erythrodermic cutaneous T-cell lymphoma (CTCL) was reported to have clinical improvement with photopheresis during the 12 months of the original study. No long-term follow-up data have been available to examine the impact of this therapy on the disease. OBJECTIVE Our purpose was to provide long-term follow-up on the original 29 erythrodermic CTCL patients treated with photopheresis and to compare these results with historical controls. METHODS Files of patients from the original photopheresis study centers were reviewed and their current status was documented. RESULTS The median survival of the treated patients was 60.33 months from the date of diagnosis and 47.9 months from the date of the start of photopheresis therapy. A complete remission has been maintained in four of the six patients who achieved complete responses in the original study. The best responses were seen in patients with a lower CD4/CD8 ratio in the peripheral blood at the start of therapy. CONCLUSION Photopheresis can influence the natural history of erythrodermic CTCL by inducing remissions and prolonging survival with minimal toxicity.
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MESH Headings
- CD4-CD8 Ratio
- Dermatitis, Exfoliative/drug therapy
- Dermatitis, Exfoliative/immunology
- Dermatitis, Exfoliative/mortality
- Dermatitis, Exfoliative/pathology
- Follow-Up Studies
- Humans
- Lymphoma, T-Cell, Cutaneous/drug therapy
- Lymphoma, T-Cell, Cutaneous/immunology
- Lymphoma, T-Cell, Cutaneous/mortality
- Lymphoma, T-Cell, Cutaneous/pathology
- Methoxsalen/therapeutic use
- Photochemotherapy
- Skin/pathology
- Skin Neoplasms/drug therapy
- Skin Neoplasms/immunology
- Skin Neoplasms/mortality
- Skin Neoplasms/pathology
- Survival Rate
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Adachi JD, Loannidis G, Berger C, Joseph L, Papaioannou A, Pickard L, Papadimitropoulos EA, Hopman W, Poliquin S, Prior JC, Hanley DA, Olszynski WP, Anastassiades T, Brown JP, Murray T, Jackson SA, Tenenhouse A. The influence of osteoporotic fractures on health-related quality of life in community-dwelling men and women across Canada. Osteoporos Int 2001; 12:903-8. [PMID: 11804016 DOI: 10.1007/s001980170017] [Citation(s) in RCA: 183] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Health-related quality of life (HRQL) was examined in relation to prevalent fractures in 4816 community-dwelling Canadian men and women 50 years and older participating in the Canadian Multicentre Osteoporosis Study (CaMos). Fractures were of three categories: clinically recognized main fractures, subclinical vertebral fractures and fractures at other sites. Main fractures were divided and analyzed at the hip, spine, wrist/forearm, pelvis and rib sites. Baseline assessments of anthropometric data, medical history, therapeutic drug use, spinal radiographs and prevalent fractures were obtained from all participants. The SF-36 instrument was used as a tool to measure HRQL. A total of 652 (13.5%) main fractures were reported. Results indicated that hip, spine, wrist/forearm, pelvis and rib fractures had occurred in 78 (1.6%), 40 (0.8%), 390 (8.1%), 19 (0.4%) and 125 (2.6%) individuals, respectively (subjects may have had more than one main fracture). Subjects who had experienced a main prevalent fracture had lower HRQL scores compared with non-fractured participants. The largest differences were observed in the physical functioning (-4.0; 95% confidence intervals (CI): -6.0, -2.0) and role-physical functioning domains (-5.8; 95% CI: -9.5, -2.2). In women, the physical functioning domain was most influenced by hip (-14.9%; 95% CI: -20.9, -9.0) and pelvis (-18.1; 95% CI: -27.6, -8.6) fractures. In men, the role-physical domain was most affected by hip fractures (-35.7; 95% CI: -60.4, -11.1). Subjects who experienced subclinical vertebral fractures had lower HRQL scores than those without prevalent fractures. In conclusion, HRQL was lower in the physical functioning domain in women and the role-physical domain in men who sustained main fractures at the hip. Subclinical vertebral fractures exerted a moderate effect on HRQL.
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183 |
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Kortunov P, Vasenkov S, Kärger J, Valiullin R, Gottschalk P, Elía MF, Perez M, Stöcker M, Drescher B, McElhiney G, Berger C, Gläser R, Weitkamp J. The Role of Mesopores in Intracrystalline Transport in USY Zeolite: PFG NMR Diffusion Study on Various Length Scales. J Am Chem Soc 2005; 127:13055-9. [PMID: 16159301 DOI: 10.1021/ja053134r] [Citation(s) in RCA: 182] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
PFG NMR has been applied to study intracrystalline diffusion in USY zeolite as well as in the parent ammonium-ion exchanged zeolite Y used to produce the USY by zeolite steaming. The diffusion studies have been performed for a broad range of molecular displacements and with two different types of probe molecules (n-octane and 1,3,5-triisopropylbenzene) having critical molecular diameters smaller and larger than the openings of the zeolite micropores. Our experimental data unambiguously show that, in contrast to what is usually assumed in the literature, the intracrystalline mesopores do not significantly affect intracrystalline diffusion in USY. This result indicates that the intracrystalline mesopores of USY zeolite do not form a connected network, which would allow diffusion through crystals only via mesopores.
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Kojima Y, Berger C, Vallee BL, Kägi JH. Amino-acid sequence of equine renal metallothionein-1B. Proc Natl Acad Sci U S A 1976; 73:3413-7. [PMID: 1068454 PMCID: PMC431125 DOI: 10.1073/pnas.73.10.3413] [Citation(s) in RCA: 172] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The amino-acid sequence of a metallothionein is reported. Metallothionein is a widely distributed, extremely cysteine-rich, low-molecular-weight protein containing large amounts of cadmium and/or zinc. Metallothionein-1B is one of the two prinicipal variants occurring in equine kidney cortex. The single-chain protein contains 61 amino acids and has the composition Cys20 Ser8Lys7Arg1Ala7Gly5Val3Asp2Asn1-Glu1Gln2Pro2Thr1Met1(Cd + Zn)7. Its amino-terminal residue is N-acetylmethionine. The sequence shows distinct clustering of the twenty cysteinyl residues into seven groups separated by stretches of at least three other residues. Within these groups the cysteines occur seven times in alternating Cys-X-Cys sequences and three times each in Cys-Cys and Cys-X-X-Cys sequences, where X is an amino acid other than cysteine. Another unique feature is the close association of serine and the basic amino acids with cysteine, as manifested by the occurrence of seven Ser-Cys, four Cys-Lys, one Cys-Arg, and three Lys-Cys sequences. These findings are in agreement with the previous suggestion that metallothionein has structurally defined metal-binding sites, most of which contain three cysteinyl residues as the principal metal-binding ligands. The charge difference between the metal-free and the metal-containing protein is consistent with the formation of negatively charged trimercaptide complexes with cadmium and/or zinc ions. The possible additional involvement of serine and the basic amino acids in metal binding is discussed.
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Sprinkle M, Ruan M, Hu Y, Hankinson J, Rubio-Roy M, Zhang B, Wu X, Berger C, de Heer WA. Scalable templated growth of graphene nanoribbons on SiC. NATURE NANOTECHNOLOGY 2010; 5:727-31. [PMID: 20890273 DOI: 10.1038/nnano.2010.192] [Citation(s) in RCA: 155] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Accepted: 08/31/2010] [Indexed: 05/18/2023]
Abstract
In spite of its excellent electronic properties, the use of graphene in field-effect transistors is not practical at room temperature without modification of its intrinsically semimetallic nature to introduce a bandgap. Quantum confinement effects can create a bandgap in graphene nanoribbons, but existing nanoribbon fabrication methods are slow and often produce disordered edges that compromise electronic properties. Here, we demonstrate the self-organized growth of graphene nanoribbons on a templated silicon carbide substrate prepared using scalable photolithography and microelectronics processing. Direct nanoribbon growth avoids the need for damaging post-processing. Raman spectroscopy, high-resolution transmission electron microscopy and electrostatic force microscopy confirm that nanoribbons as narrow as 40 nm can be grown at specified positions on the substrate. Our prototype graphene devices exhibit quantum confinement at low temperatures (4 K), and an on-off ratio of 10 and carrier mobilities up to 2,700 cm(2) V(-1) s(-1) at room temperature. We demonstrate the scalability of this approach by fabricating 10,000 top-gated graphene transistors on a 0.24-cm(2) SiC chip, which is the largest density of graphene devices reported to date.
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Kristen KH, Berger C, Stelzig S, Thalhammer E, Posch M, Engel A. The SCARF osteotomy for the correction of hallux valgus deformities. Foot Ankle Int 2002; 23:221-9. [PMID: 11934064 DOI: 10.1177/107110070202300306] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The authors report their experience with a modified SCARF osteotomy with three years follow-up. Correction of moderate to severe hallux valgus deformities was achieved using a Z step osteotomy cut to realign the first metatarsal bone. A retrospective analysis was undertaken in 89 consecutive patients (111 feet). Results were analyzed by clinical examination, a questionnaire including the AOFAS forefoot score, and plain roentgenograms. Hallux valgus and intermetatarsal angle improved at mean 19.1 degrees and 6.6 degrees, respectively. Mean forefoot score improved from 50.1 to 91 points out of 100 possible points. Satisfactory healing time was expressed by an average return back to work of 5.8 weeks and back to sport of 8.3 weeks. Persistence or recurrence of hallux valgus was seen in seven patients (6%). The complication rate was 5.4% including superficial wound infection, traumatic dislocation of the distal fragment, and hallux limitus. The presented technique provides predictable correction of moderate to severe hallux valgus deformities.
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Berger C, de Muret A, Garaud P, Chapet S, Bourlier P, Reynaud-Bougnoux A, Dorval E, de Calan L, Huten N, le Folch O, Calais G. Preoperative radiotherapy (RT) for rectal cancer: predictive factors of tumor downstaging and residual tumor cell density (RTCD): prognostic implications. Int J Radiat Oncol Biol Phys 1997; 37:619-27. [PMID: 9112461 DOI: 10.1016/s0360-3016(96)00577-9] [Citation(s) in RCA: 145] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
PURPOSE To determine predictive factors and prognostic value of tumor downstaging and tumor sterilization after preoperative RT for rectal cancer. METHODS AND MATERIALS Between 1977 and 1994, 167 patients with a histologically proven adenocarcinoma (70 T2, 65 T3, 29 T4, and 3 local recurrences) underwent preoperative RT. Median dose was 44 Gy (5-73 Gy). Surgery was performed in a mean time of 5 weeks after RT. Pathologic specimens have been reviewed by the same pathologist in order to specify the modified Astler Coller classification (MAC), and to quantify the residual tumor cell density (RTCD). RESULTS According to the MAC, there was 9 stage 0 (5%), 10 stage A (6%), 103 stage B1-B3 (62%), and 45 stage C1-C3 (27%) tumors. Seventeen percent and 56% of the patients who received a dose > or = 44 Gy had respectively a 0-A and a B tumor, compared to 4 and 69% in those who received a dose < 44 Gy (p = 0.04). Tumor differentiation and a longer interval before surgery were significantly associated with a more frequent downstaging, and preoperative staging correlated well to the postoperative pathological findings. According to the RTCD, 62 tumors (37%) showed no or only rare foci of residual tumor cells (Group 1); 62 (37%) showed an intermediate RTCD (Group 2); and 43 (26%) a high RTCD (Group 3). No predictive factor of RTCD was statistically significant. In univariate analysis, postoperative staging was a significant prognostic factor, with corresponding 5-year overall survival rates in 0-A, B, and C stages of 92, 67, and 26% (p < 0.01). RTCD was not a prognostic factor. However, overall and disease-free survival rates for patients with complete pathologic response of 83% at 2 and 5 years suggested a better outcome in this subgroup of patients. CONCLUSION The favorable influence of higher doses of preoperative RT on pathologic stage has been observed. Tumor differentiation, preoperative classification and time before surgery were the other predictive factors of tumor downstaging. However, there was no predictive factor of complete pathologic response. Even after preoperative RT, postoperative staging remained a prognostic factor.
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Fraser LA, Langsetmo L, Berger C, Ioannidis G, Goltzman D, Adachi JD, Papaioannou A, Josse R, Kovacs CS, Olszynski WP, Towheed T, Hanley DA, Kaiser SM, Prior J, Jamal S, Kreiger N, Brown JP, Johansson H, Oden A, McCloskey E, Kanis JA, Leslie WD. Fracture prediction and calibration of a Canadian FRAX® tool: a population-based report from CaMos. Osteoporos Int 2011; 22:829-37. [PMID: 21161508 PMCID: PMC5101064 DOI: 10.1007/s00198-010-1465-1] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Accepted: 09/03/2010] [Indexed: 10/18/2022]
Abstract
UNLABELLED A new Canadian WHO fracture risk assessment (FRAX®) tool to predict 10-year fracture probability was compared with observed 10-year fracture outcomes in a large Canadian population-based study (CaMos). The Canadian FRAX tool showed good calibration and discrimination for both hip and major osteoporotic fractures. INTRODUCTION The purpose of this study was to validate a new Canadian WHO fracture risk assessment (FRAX®) tool in a prospective, population-based cohort, the Canadian Multicentre Osteoporosis Study (CaMos). METHODS A FRAX tool calibrated to the Canadian population was developed by the WHO Collaborating Centre for Metabolic Bone Diseases using national hip fracture and mortality data. Ten-year FRAX probabilities with and without bone mineral density (BMD) were derived for CaMos women (N = 4,778) and men (N = 1,919) and compared with observed fracture outcomes to 10 years (Kaplan-Meier method). Cox proportional hazard models were used to investigate the contribution of individual FRAX variables. RESULTS Mean overall 10-year FRAX probability with BMD for major osteoporotic fractures was not significantly different from the observed value in men [predicted 5.4% vs. observed 6.4% (95%CI 5.2-7.5%)] and only slightly lower in women [predicted 10.8% vs. observed 12.0% (95%CI 11.0-12.9%)]. FRAX was well calibrated for hip fracture assessment in women [predicted 2.7% vs. observed 2.7% (95%CI 2.2-3.2%)] but underestimated risk in men [predicted 1.3% vs. observed 2.4% (95%CI 1.7-3.1%)]. FRAX with BMD showed better fracture discrimination than FRAX without BMD or BMD alone. Age, body mass index, prior fragility fracture and femoral neck BMD were significant independent predictors of major osteoporotic fractures; sex, age, prior fragility fracture and femoral neck BMD were significant independent predictors of hip fractures. CONCLUSION The Canadian FRAX tool provides predictions consistent with observed fracture rates in Canadian women and men, thereby providing a valuable tool for Canadian clinicians assessing patients at risk of fracture.
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Leslie WD, Lix LM, Langsetmo L, Berger C, Goltzman D, Hanley DA, Adachi JD, Johansson H, Oden A, McCloskey E, Kanis JA. Construction of a FRAX® model for the assessment of fracture probability in Canada and implications for treatment. Osteoporos Int 2011; 22:817-27. [PMID: 21161509 DOI: 10.1007/s00198-010-1464-2] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/09/2010] [Accepted: 08/31/2010] [Indexed: 11/27/2022]
Abstract
UNLABELLED We describe the creation of a FRAX® model for the assessment of fracture probability in Canadian men and women, calibrated from national hip fracture and mortality data. This FRAX tool was used to examine possible thresholds for therapeutic intervention in Canada in two large complementary cohorts of women and men. OBJECTIVE To evaluate a Canadian World Health Organization (WHO) fracture risk assessment (FRAX®) tool for computing 10-year probabilities of osteoporotic fracture. METHODS Fracture probabilities were computed from national hip fracture data (2005) and death hazards (2004) for Canada. Probabilities took account of age, sex, clinical risk factors (CRFs), and femoral neck bone mineral density (BMD). Treatment implications were studied in two large cohorts of individuals age 50 years and older: the population-based Canadian Multicentre Osteoporosis Study (4,778 women and 1,919 men) and the clinically referred Manitoba BMD Cohort (36,730 women and 2,873 men). RESULTS Fracture probabilities increased with age, decreasing femoral neck T-score, and number of CRFs. Among women, 10.1-11.3% would be designated high risk based upon 10-year major osteoporotic fracture probability exceeding 20%. A much larger proportion would be designated high risk based upon 10-year hip fracture probability exceeding 3% (25.7-28.0%) or osteoporotic BMD (27.1-30.9%), and relatively few from prior hip or clinical spine fracture (1.6-4.2%). One or more criteria for intervention were met by 29.2-34.0% of women excluding hip fracture probability (35.3-41.0% including hip fracture probability). Lower intervention rates were seen among CaMos (Canadian Multicentre Osteoporosis Study) men (6.8-12.9%), but in clinically referred men from the Manitoba BMD Cohort, one or more criteria for high risk were seen for 26.4% excluding hip fracture probability (42.4% including hip fracture probability). CONCLUSIONS The FRAX tool can be used to identify intervention thresholds in Canada. The FRAX model supports a shift from a dual X-ray absorptiometry (DXA)-based intervention strategy, towards a strategy based on fracture probability for a major osteoporotic fracture.
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Wendt H, Berger C, Baici A, Thomas RM, Bosshard HR. Kinetics of folding of leucine zipper domains. Biochemistry 1995; 34:4097-107. [PMID: 7696274 DOI: 10.1021/bi00012a028] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Leucine zippers are short coiled coils frequently found in transcription factors where they serve as dimerization domains. The basic features contributing to the thermodynamic stability of leucine zippers are well understood, but very little is known about their folding kinetics. Leucine zippers have a simple and well defined structure and are, therefore, excellent models for the study of the concerted folding and assembly of polypeptide chains. Here we report on a fluorescence stopped flow investigation of the kinetics of association and dissociation of a series of model leucine zippers based on the common sequence Xzero-EYEALEKKLAAX1EAKX2QALEKKLEALEHG-amide (Xzero = N alpha-acetyl, N alpha-fluorescein-GGG, or N alpha-dimethylaminocoumarin-GGG; Xl = Leu or Ala; X2 = Leu, Ala, or Asn). When Xzero is fluorescein, self-quenching between adjacent fluorophores leads to a decrease in fluorescence emission intensity whereas unfolding of the coiled coil leads to an increase. In a heteromeric coiled coil containing both fluorophores, resonance energy transfer between the donor coumarin and the acceptor fluorescein is observed, and the mixing of labeled and nonlabeled peptides allows the measurement of the rates of strand exchange between leucine zippers. Exchange rates do not depend on peptide concentration, indicating that strand exchange is governed by the rate of dissociation of the coiled coil. Strand exchange between leucine zippers with X1 and X2 = Leu occurs with a half-time of approximately 30 min. A single Leu/Ala substitution at X1 or X2 decreases the half-time to approximately 1 s. Folding was also studied in a relaxation experiment in which a preexisting equilibrium between monomeric chains and coiled coils was rapidly disturbed by dilution with buffer, and the relaxation to the new equilibrium was followed by the increase in fluorescence. In peptides with X1, X2 = Ala or X1 = Ala, X2 = Asn the folding process can be described by a simple two-state monomer<-->dimer equilibrium with k(on) approximately 4 x 10(6) M-1 s-1 and k(off) approximately 10 s-1. Kd = k(off)/k(on) approximately 2.5 microM is in good agreement with the value of Kd obtained from equilibrium measurements. The peptides with a single Ala at X1 or X2 exhibit biphasic folding kinetics. One phase is concentration dependent and the other apparently concentration independent. This behavior can be interpreted as a monomer<-->dimer equilibrium coupled to an equilibrium between different conformational isomers. Leu to Ala and Leu to Asn substitutions in the hydrophobic core alter the folding kinetics in a position-dependent manner.(ABSTRACT TRUNCATED AT 400 WORDS)
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Sprinkle M, Siegel D, Hu Y, Hicks J, Tejeda A, Taleb-Ibrahimi A, Le Fèvre P, Bertran F, Vizzini S, Enriquez H, Chiang S, Soukiassian P, Berger C, de Heer WA, Lanzara A, Conrad EH. First direct observation of a nearly ideal graphene band structure. PHYSICAL REVIEW LETTERS 2009; 103:226803. [PMID: 20366119 DOI: 10.1103/physrevlett.103.226803] [Citation(s) in RCA: 126] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Indexed: 05/29/2023]
Abstract
Angle-resolved photoemission and x-ray diffraction experiments show that multilayer epitaxial graphene grown on the SiC(0001) surface is a new form of carbon that is composed of effectively isolated graphene sheets. The unique rotational stacking of these films causes adjacent graphene layers to electronically decouple leading to a set of nearly independent linearly dispersing bands (Dirac cones) at the graphene K point. Each cone corresponds to an individual macroscale graphene sheet in a multilayer stack where AB-stacked sheets can be considered as low density faults.
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Bosset JF, Calais G, Daban A, Berger C, Radosevic-Jelic L, Maingon P, Bardet E, Pierart M, Briffaux A. Preoperative chemoradiotherapy versus preoperative radiotherapy in rectal cancer patients: assessment of acute toxicity and treatment compliance. Eur J Cancer 2004; 40:219-24. [PMID: 14728936 DOI: 10.1016/j.ejca.2003.09.032] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The European Organisation for Research and Treatment of Cancer (EORTC) 22921 four-arm randomised trial questioned the value of preoperative chemoradiation (XRT-CT) versus preoperative radiation (XRT) and the value of additional postoperative chemotherapy (CT) versus none in T3-T4 M0 resectable rectal cancer patients. We report on the preoperative toxicity, treatment compliance and early deaths (all deaths up to 30 days after surgery) of the two treatment modalities in patients who were entered into trial before January 2001. In the XRT Group (group A), patients received 45 Gy, 25 fractions over 5 weeks. In the XRT-CT Group (group B), two 5-day courses of CT were added to the first and fifth weeks of XRT. For each CT course: 5-fluorouracil (5-FU) 350 mg/m2/day and Leucovorin (LV) 20 mg/m2/day were given. 398 and 400 patients started treatment in groups A and B, respectively. Grade 2+acute diarrhoea occurred in 17.3 and 34.3% of patients in groups A and B, respectively (P<0.005). The other side-effects remained unchanged or were only marginally increased. The compliance with RT was 98.5 and 95.5% in groups A and B, respectively. In group B, 78.7 and 71.1% of the patients received 95-105% of the planned CT doses at the first and second courses, respectively. 6 patients died preoperatively, 2 from toxicity in group B. 8 patients (1%) died within the 30 days after surgery in both groups. At the doses recommended in the protocol, the addition of 5-FU-LV to preoperative XRT slightly increased the amount of acute toxicity. However, the compliance with the radiation protocol or the feasibility of surgery did not decrease.
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Greene-Finestone LS, Berger C, de Groh M, Hanley DA, Hidiroglou N, Sarafin K, Poliquin S, Krieger J, Richards JB, Goltzman D. 25-Hydroxyvitamin D in Canadian adults: biological, environmental, and behavioral correlates. Osteoporos Int 2011; 22:1389-99. [PMID: 20730415 PMCID: PMC5102696 DOI: 10.1007/s00198-010-1362-7] [Citation(s) in RCA: 120] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2010] [Accepted: 07/13/2010] [Indexed: 12/15/2022]
Abstract
SUMMARY We assessed vitamin D status and its correlates in the population-based Canadian Multicentre Osteoporosis Study (CaMos). Results showed that serum 25-hydroxyvitamin D levels <75 nmol/L were common. Given Canada's high latitude, attention should be given to strategies for enhancing vitamin D status in the population. INTRODUCTION Inadequate vitamin D has been implicated as a risk factor for several clinical disorders. We assessed, in a Canadian cohort, vitamin D status and its correlates, based on serum 25-hydroxyvitamin D [25(OH)D], the best functional indicator of vitamin D status. METHODS We studied 577 men and 1,335 women 35+ years from seven cities across Canada in the randomly selected, population-based Canadian Multicentre Osteoporosis Study (CaMos). Participants completed a comprehensive questionnaire. Serum 25(OH)D was measured by immunoassay. Multivariate linear regression modeling assessed the association between 25(OH)D and determinants of vitamin D status. RESULTS Participants (2.3%) were deficient in 25(OH)D (<27.5 nmol/L); a further 18.1% exhibited 25(OH)D insufficiency (27.5-50 nmol/L). Levels <75 nmol/L were evident in 57.5% of men and 60.7% of women and rose to 73.5% in spring (men) and 77.5% in winter (women); 25(OH)D <50 nmol/L was ≤10% year round for those supplementing with ≥400 IU vitamin D/day but was 43.9% among those not supplementing in winter and spring. The strongest predictors of reduced 25(OH)D for both men and women were winter and spring season, BMI ≥30, non-white ethnicity, and lower vitamin D supplementation and its modification by fall and winter. CONCLUSIONS In this national Canadian cohort, vitamin D levels <75 nmol/L were common, particularly among non-white and obese individuals, and in winter and spring. Vitamin D intake through diet and supplementation and maintenance of normal weight are key modifiable factors for enhancing vitamin D status and thus potentially influencing susceptibility to common chronic diseases.
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Hanley DA, Brown JP, Tenenhouse A, Olszynski WP, Ioannidis G, Berger C, Prior JC, Pickard L, Murray TM, Anastassiades T, Kirkland S, Joyce C, Joseph L, Papaioannou A, Jackson SA, Poliquin S, Adachi JD. Associations among disease conditions, bone mineral density, and prevalent vertebral deformities in men and women 50 years of age and older: cross-sectional results from the Canadian Multicentre Osteoporosis Study. J Bone Miner Res 2003; 18:784-90. [PMID: 12674340 DOI: 10.1359/jbmr.2003.18.4.784] [Citation(s) in RCA: 117] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
This cross-sectional cohort study of 5566 women and 2187 men 50 years of age and older in the population-based Canadian Multicentre Osteoporosis Study was conducted to determine whether reported past diseases are associated with bone mineral density or prevalent vertebral deformities. We examined 12 self-reported disease conditions including diabetes mellitus (types 1 or 2), nephrolithiasis, hypertension, heart attack, rheumatoid arthritis, thyroid disease, breast cancer, inflammatory bowel disease, neuromuscular disease, Paget's disease, and chronic obstructive pulmonary disease. Multivariate linear and logistic regression analyses were performed to determine whether there were associations among these disease conditions and bone mineral density of the lumbar spine, femoral neck, and trochanter, as well as prevalent vertebral deformities. Bone mineral density measurements were higher in women and men with type 2 diabetes compared with those without after appropriate adjustments. The differences were most notable at the lumbar spine (+0.053 g/cm2), femoral neck (+0.028 g/cm2), and trochanter (+0.025 g/cm2) in women, and at the femoral neck (+0.025 g/cm2) in men. Hypertension was also associated with higher bone mineral density measurements for both women and men. The differences were most pronounced at the lumbar spine (+0.022 g/cm2) and femoral neck (+0.007 g/cm2) in women and at the lumbar spine (+0.028 g/cm2) in men. Although results were statistically inconclusive, men reporting versus not reporting past nephrolithiasis appeared to have clinically relevant lower bone mineral density values. Bone mineral density differences were -0.022, -0.015, and -0.016 g/cm2 at the lumbar spine, femoral neck, and trochanter, respectively. Disease conditions were not strongly associated with vertebral deformities. In summary, these cross-sectional population-based data show that type 2 diabetes and hypertension are associated with higher bone mineral density in women and men, and nephrolithiasis may be associated with lower bone mineral density in men. The importance of these associations for osteoporosis case finding and management require further and prospective studies.
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