342 research outputs found

    The role of obesity, different fat compartments and sleep apnea severity in circulating leptin levels: the Icelandic Sleep Apnea Cohort study.

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    To access publisher's full text version of this article. Please click on the hyperlink in Additional Links field.To assess whether sleep apnea severity has an independent relationship with leptin levels in blood after adjusting for different measures of obesity and whether the relationship between obstructive sleep apnea (OSA) severity and leptin levels differs depending on obesity level.Cross-sectional study of 452 untreated OSA patients (377 males and 75 females), in the Icelandic Sleep Apnea Cohort (ISAC), age 54.3±10.6 (mean±s.d.), body mass index (BMI) 32.7±5.3 kg m(-2) and apnea-hypopnea index 40.2±16.1 events per h. A sleep study and magnetic resonance imaging of abdominal visceral and subcutaneous fat volume were performed, as well as fasting serum morning leptin levels were measured.Leptin levels were more highly correlated with BMI, total abdominal and subcutaneous fat volume than visceral fat volume per se. No relationship was found between sleep apnea severity and leptin levels, assessed within three BMI groups (BMI or =35 kg m(-2)). In a multiple linear regression model, adjusted for gender, BMI explained 38.7% of the variance in leptin levels, gender explained 21.2% but OSA severity did not have a significant role and no interaction was found between OSA severity and BMI on leptin levels. However, hypertension had a significant effect on the interaction between OSA severity and obesity (P=0.04). In post-hoc analysis for nonhypertensive OSA subjects (n=249), the association between leptin levels and OSA severity explained a minor but significant variance (3.2%) in leptin levels. This relationship was greatest for nonobese nonhypertensive subjects (significant interaction with obesity level). No relationship of OSA severity and leptin levels was found for hypertensive subjects (n=199).Obesity and gender are the dominant determinants of leptin levels. OSA severity is not related to leptin levels except to a minor degree in nonhypertensive nonobese OSA subjects.NIH/HL72067/HL94307, Eimskip Fund of the University of Iceland, Landspitali University Hospital Research Fun

    Cladribine with cyclophosphamide and prednisone in the management of low-grade lymphoproliferative malignancies

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    The feasibility of combining cladribine with cyclophosphamide and prednisone in the management of indolent lymphoid malignancies was determined. Nineteen patients [nine chronic lymphocytic leukaemia (CLL), seven non-Hodgkin's lymphoma (NHL) and three macroglobulinaemia (M))] received cladribine 0.1 mg kg−1 per day as a subcutaneous bolus injection on days 1–3 (up to 5 injections) with intravenous cyclophosphamide 500 mg m−2 on day 1 and oral prednisone 40 mg m−2 on days 1–5 at 4-weekly intervals up to a maximum of six courses. A total of 80 courses were given. Overall response rate was 88%, with four patients achieving a complete clinical and haematological response and 12 achieving a partial response. Neutropenia WHO grade 4 in two patients and WHO grade 3 infection in one patient were the limiting toxicities on treatment. During the follow-up, WHO grade ≥3 haematological complications occurred in five patients and WHO grade ≥3 non-haematological complications in five patients. There were no treatment-related deaths. This study demonstrates the feasibility of the cladribine/cyclophosphamide/prednisone (CCP) combination that appears highly active and safe in the management of indolent lymphoid malignancies. © 1999 Cancer Research Campaig

    Long-Term Effectiveness and Safety of Childhood Growth Hormone Treatment in Noonan Syndrome

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    Introduction: Few data exist on long-term growth hormone (GH) treatment in patients with Noonan syndrome (NS). Objective: To evaluate the effectiveness and safety of GH treatment in NS in clinical practice. Methods: Height gain, near-adult height (NAH), and safety were assessed in 2 complementary non-interventional studies: NordiNet® IOS and ANSWER. The safety analysis included 412 patients, and the effectiveness analysis included 84 GH-treated patients (male, n = 67) with ≥4 years’ height standard deviation score (HSDS) data. HSDS was determined using national reference (NR) and NS-specific (NSS) data. Results: The mean (SD) baseline age was 8.38 (3.57) years; HSDS, −2.76 (1.03); GH dose, 41.6 (11.1) µg/kg/day. The mean (SD) HSDS increase from baseline (ΔHSDS) was 0.49 (0.37) (first year), 0.79 (0.58) (second year), and 1.01 (0.60) (third year) (NR). The mean (SD) HSDS at year 3 was −1.66 (1.00) (NR; 1.06 [1.12] [NSS]). Twenty-four patients achieved NAH. The mean (SD) NAH SDS (NR) was −1.51 (0.60) (154.90 [3.21] cm) in females and −1.79 (1.09) (165.61 [7.19] cm) in males; 70.8% (17/24) had NAH SDS ≥ −2. Adverse drug reactions and GH-unrelated serious adverse events (n = 34) were reported in 22/412 (5.3%) patients. Four neoplasms and 3 cases of scoliosis were reported; no cardiovascular adverse events occurred. Conclusions: GH-treated children with NS achieved substantial height gain during the first 3 years of follow-up. Overall, 24 patients achieved NAH, with 70.8% having NAH SDS ≥ –2. There was no evidence to support a higher prevalence of neoplasm, or cardiac or other comorbidities.publishedVersio

    The Composition of Cosmic Rays at the Knee

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    The observation of a small change in spectral slope, or 'knee' in the fluxes of cosmic rays near energies 10^15 eV has caused much speculation since its discovery over 40 years ago. The origin of this feature remains unknown. A small workshop to review some modern experimental measurements of this region was held at the Adler Planetarium in Chicago, USA in June 2000. This paper summarizes the results presented at this workshop and the discussion of their interpretation in the context of hadronic models of atmospheric airshowers.Comment: 36 pages, 10 figure

    A study on the sharp knee and fine structures of cosmic ray spectra

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    The paper investigates the overall and detailed features of cosmic ray (CR) spectra in the knee region using the scenario of nuclei-photon interactions around the acceleration sources. Young supernova remnants can be the physical realities of such kind of CR acceleration sites. The results show that the model can well explain the following problems simultaneously with one set of source parameters: the knee of CR spectra and the sharpness of the knee, the detailed irregular structures of CR spectra, the so-called "component B" of Galactic CRs, and the electron/positron excesses reported by recent observations. The coherent explanation serves as evidence that at least a portion of CRs might be accelerated at the sources similar to young supernova remnants, and one set of source parameters indicates that this portion mainly comes from standard sources or from a single source.Comment: 13 pages, 4 figures, accepted for publication in SCIENCE CHINA Physics, Mechanics & Astronomy

    Islands of change vs. islands of disaster: Managing pigs and birds in the Anthropocene of the North Atlantic

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    The offshore islands of the North Atlantic were among some of the last settled places on earth, with humans reaching the Faroes and Iceland in the late Iron Age and Viking period. While older accounts emphasizing deforestation and soil erosion have presented this story of island colonization as yet another social–ecological disaster, recent archaeological and paleoenvironmental research combined with environmental history, environmental humanities, and bioscience is providing a more complex understanding of long-term human ecodynamics in these northern islands. An ongoing interdisciplinary investigation of the management of domestic pigs and wild bird populations in Faroes and Iceland is presented as an example of sustained resource management using local and traditional knowledge to create structures for successful wild fowl management on the millennial scale

    On the knee in the energy spectrum of cosmic rays

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    The knee in the all-particle energy spectrum is scrutinized with a phenomenological model, named poly-gonato model, linking results from direct and indirect measurements. For this purpose, recent results from direct and indirect measurements of cosmic rays in the energy range from 10 GeV up to 1 EeV are examined. The energy spectra of individual elements, as obtained by direct observations, are extrapolated to high energies using power laws and compared to all-particle spectra from air shower measurements. A cut-off for each element proportional to its charge Z is assumed. The model describes the knee in the all-particle energy spectrum as a result of subsequent cut-offs for individual elements, starting with the proton component at 4.5 PeV, and the second change of the spectral index around 0.4 EeV as due to the end of stable elements (Z=92). The mass composition, extrapolated from direct measurements to high energies, using the poly-gonato model, is compatible with results from air shower experiments measuring the electromagnetic, muonic, and hadronic components. But it disagrees with the mass composition derived from X_max measurements using Cerenkov and fluorescence light detectors.Comment: 30 pages, 21 figures, 9 tables, accepted by Astroparticle Physic

    Cosmic-ray composition and its relation to shock acceleration by supernova remnants

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    An overview is given on the present status of the understanding of the origin of galactic cosmic rays. Recent measurements of charged cosmic rays and photons are reviewed. Their impact on the contemporary knowledge about the sources and acceleration mechanisms of cosmic rays and their propagation through the Galaxy is discussed. Possible reasons for the knee in the energy spectrum and scenarios for the end of the galactic cosmic-ray component are described.Comment: Invited talk given at the 36th COSPAR Scientific Assembly Beijing, China, 16 -- 23 July 2006 - submitted to Advances in Space Research - comments are welcom

    PAPSS2‐related brachyolmia : clinical and radiological phenotype in 18 new cases

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    Brachyolmia is a skeletal dysplasia characterized by short spine‐short stature, platyspondyly, and minor long bone abnormalities. We describe 18 patients, from different ethnic backgrounds and ages ranging from infancy to 19 years, with the autosomal recessive form, associated with PAPSS2. The main clinical features include disproportionate short stature with short spine associated with variable symptoms of pain, stiffness, and spinal deformity. Eight patients presented prenatally with short femora, whereas later in childhood their short‐spine phenotype emerged. We observed the same pattern of changing skeletal proportion in other patients. The radiological findings included platyspondyly, irregular end plates of the elongated vertebral bodies, narrow disc spaces and short over‐faced pedicles. In the limbs, there was mild shortening of femoral necks and tibiae in some patients, whereas others had minor epiphyseal or metaphyseal changes. In all patients, exome and Sanger sequencing identified homozygous or compound heterozygous PAPSS2 variants, including c.809G>A, common to white European patients. Bi‐parental inheritance was established where possible. Low serum DHEAS, but not overt androgen excess was identified. Our study indicates that autosomal recessive brachyolmia occurs across continents and may be under‐recognized in infancy. This condition should be considered in the differential diagnosis of short femora presenting in the second trimester
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