bluuebunny/crossref_metadata_2025_split huggingface dataset:
Insulin Reciprocally Regulates Glucagon Secretion in Humans
Authors: Cooperberg Benjamin A. , Cryer Philip E. 
Published: September 2010

OBJECTIVE
We tested the hypothesis that an increase in insulin per se, i.e., in the absence of zinc, suppresses glucagon secretion during euglycemia and that a decrease in insulin per se stimulates glucagon secretion during hypoglycemia in humans.

RESEARCH DESIGN AND METHODS
We measured plasma glucagon concentrations in patients with type 1 diabetes infused with the zinc-free insulin glulisine on three occasions. Glulisine was infused with clamped euglycemia (∼95 mg/dl [5.3 mmol/l]) from 0 to 60 min on all three occasions. Then, glulisine was discontinued with clamped euglycemia or with clamped hypoglycemia (∼55 mg/dl [3.0 mmol/l]) or continued with clamped hypoglycemia from 60 to 180 min.

RESULTS
Plasma glucagon concentrations were suppressed by −13 ± 3, −9 ± 3, and −12 ± 2 pg/ml (−3.7 ± 0.9, −2.6 ± 0.9, and −3.4 ± 0.6 pmol/l), respectively, (all P &lt; 0.01) during zinc-free hyperinsulinemic euglycemia over the first 60 min. Glucagon levels remained suppressed following a decrease in zinc-free insulin with euglycemia (−14 ± 3 pg/ml [−4.0 ± 0.9 pmol/l]) and during sustained hyperinsulinemia with hypoglycemia (−14 ± 2 pg/ml [−4.0 ± 0.6 pmol/l]) but increased to −3 ± 3 pg/ml (−0.9 ± 0.9 pmol/l) (P &lt; 0.01) following a decrease in zinc-free insulin with hypoglycemia over the next 120 min.

CONCLUSIONS
These data indicate that an increase in insulin per se suppresses glucagon secretion and a decrease in insulin per se, in concert with a low glucose concentration, stimulates glucagon secretion. Thus, they document that insulin is a β-cell secretory product that, in concert with glucose and among other signals, reciprocally regulates α-cell glucagon secretion in humans.
Evidence of past migration of the ice divide between the Shirase and Sôya drainage basins derived from chemical characteristics of the marginal ice in the Sôya drainage basin, East Antarctica
Authors: Iizuka Yoshinori , Miura Hideki , Iwasaki Shogo , Maemoku Hideaki , Sawagaki Takanobu , Greve Ralf , Satake Hiroshi , Sasa Kimikazu , Matsushi Yuki 
Published: September 2010

AbstractIce originating near the inland ice divide of the ice sheet can reappear as marginal ice at the surface near the ice terminal in the ablation area. We have analyzed δ18O values and ion concentrations of the Skallen, Skarvsnes and Hamna terminal ice sections, located along the estuary line in the Sôya drainage basin, East Antarctica. The data suggest that the upper part of the Skallen terminal ice section could have originated from inland precipitation on the Shirase drainage basin during marine isotope stage (MIS) 5e, while the upper part of Skarvsnes and Hamna terminal ice sections could have originated from inland precipitation on the Sôya drainage basin. We calculate past elevation maps for the Antarctic ice sheet using the three-dimensional model, SICOPOLIS. This model suggests that the upstream portion of the Sôya drainage basin during the glacial period (MIS 2, 3 or 4) was located to the northeast of its present location. A flow history is proposed wherein ice from the inland Shirase drainage area flowed over the present ice-divide line from the Shirase to the Sôya drainage basin during the glacial period. The ice in the Sôya drainage basin then flowed to the marginal part of the sheet after the ice divide had assumed its present position.
Effects of debris on ice-surface melting rates: an experimental study
Authors: Reznichenko Natalya , Davies Tim , Shulmeister James , McSaveney Mauri 
Published: September 2010

AbstractHere we report a laboratory study of the effects of debris thickness, diurnally cyclic radiation and rainfall on melt rates beneath rock-avalanche debris and sand (representing typical highly permeable supraglacial debris). Under continuous, steady-state radiation, sand cover >50 mm thick delays the onset of ice-surface melting by >12 hours, but subsequent melting matches melt rates of a bare ice surface. Only when diurnal cycles of radiation are imposed does the debris reduce the longterm rate of ice melt beneath it. This is because debris >50 mm thick never reaches a steady-state heat flux, and heat acquired during the light part of the cycle is partially dissipated to the atmosphere during the nocturnal part of the cycle, thereby continuously reducing total heat flux to the ice surface underneath. The thicker the debris, the greater this effect. Rain advects heat from high-permeability supraglacial debris to the ice surface, thereby increasing ablation where thin, highly porous material covers the ice. In contrast, low-permeability rock-avalanche material slows water percolation, and heat transfer through the debris can cease when interstitial water freezes during the cold/night part of the cycle. This frozen interstitial water blocks heat advection to the ice–debris contact during the warm/day part of the cycle, thereby reducing overall ablation. The presence of metre-deep rock-avalanche debris over much of the ablation zone of a glacier can significantly affect the mass balance, and thus the motion, of a glacier. The length and thermal intensity of the diurnal cycle are important controls on ablation, and thus both geographical location and altitude significantly affect the impact of debris on glacial melting rates; the effect of debris cover is magnified at high altitude and in lower latitudes.
Greenland flow variability from ice-sheet-wide velocity mapping
Authors: Joughin Ian , Smith Ben E. , Howat Ian M. , Scambos Ted , Moon Twila 
Published: September 2010

AbstractUsing RADARSAT synthetic aperture radar data, we have mapped the flow velocity over much of the Greenland ice sheet for the winters of 2000/01 and 2005/06. These maps provide a detailed view of the ice-sheet flow, including that of the hundreds of glaciers draining the interior. The focused patterns of flow at the coast suggest a strong influence of bedrock topography. Differences between our two maps confirm numerous early observations of accelerated outlet glacier flow as well as revealing previously unrecognized changes. The overall pattern is one of speed-up accompanied by terminus retreat, but there are also several instances of surge behavior and a few cases of glacier slowdown. Comprehensive mappings such as these, at regular intervals, provide an important new observational capability for understanding ice-sheet variability.
Ice friction: the effect of thermal conductivity
Authors: Kietzig Anne-Marie , Hatzikiriakos Savvas G. , Englezos Peter 
Published: September 2010

AbstractThe effect of thermal conductivity on ice friction is studied systematically for different metallic slider materials over a wide range of temperatures, and sliding velocities. By thermally insulating the slider with fiberglass, the isolated effect of thermal conductivity on ice friction is investigated. A decrease of the friction coefficient in the boundary friction regime and an earlier onset of the mixed friction regime in terms of sliding velocity are found. Furthermore, the dependence of the ice friction coefficient on sliding velocity is compared for different sliding materials. It is found that the influence and importance of thermal conductivity decreases with increasing sliding velocity.
Snow grain-size profiles deduced from microwave snow emissivities in Antarctica
Authors: Brucker Ludovic , Picard Ghislain , Fily Michel 
Published: September 2010

AbstractSpaceborne microwave radiometers are an attractive tool for observing Antarctic climate because their measurements are related to the snow temperature. However, the conversion from microwave emission to snow temperature is not simple and strongly depends on the emissivity through snow properties. This difficulty in predicting the snow property profile for Antarctic conditions is the main bottleneck in the retrieval of accurate climate information from microwave radiometers. We attempt to explain the vertically polarized emissivity at 19.3 and 37 GHz derived from brightness temperatures acquired by the Special Sensor Microwave/Imager (SSM/I) and physical temperature from the ERA-40 re-analysis. In Antarctica the snow emissivities at 19.3 and 37 GHz are nearly equal, although a decrease with frequency is expected. To explain this, we consider various profiles of snow grain size and density and predict their emissivity using a dense-medium radiative transfer (DMRT) model. The results show that the emissivities cannot be explained by constant profiles of grain size and density. Heterogeneous snowpacks need to be considered. We first test random variations of snow density and grain radius with depth and then monotonic and continuous variations in the snow grain radius. In both cases, we show that an overall increase of the snow grain radius with depth is required to match the observed emissivity in Antarctica. In addition, two parameters characterizing the snow grain profiles are retrieved and compared with (1) in situ measurements of grain size at various locations in East Antarctica, (2) grain size estimated using visible spaceborne radiometers and (3) a semi-empirical relationship for grain growth.
Grounding-line basal melt rates determined using radar-derived internal stratigraphy
Authors: Catania Ginny , Hulbe Christina , Conway Howard 
Published: September 2010

AbstractWe use ice-penetrating radar data across grounding lines of Siple Dome and Roosevelt Island, Antarctica, to measure the spatial pattern, magnitude and duration of sub-ice-shelf melting at these locations. Stratigraphic layers across the grounding line show, in places, a large-amplitude downwarp at, or slightly downstream of, the grounding line due to sub-ice-shelf basal melting. Localized downwarping indicates that melting is transient; melt rates, or the grounding line position, have changed within a few hundred years in order to produce the observed stratigraphy. Elsewhere, no melt-related stratigraphic signature is preserved. In part, heterogeneity in the amount of sub-ice-shelf melt is due to regional circulation patterns in the sub-shelf cavity, but local (on the order of tens of kilometers) heterogeneity in the melt pattern may reflect small differences in the shape of the ice-shelf base at the grounding line. We find that all of the grounding lines crossed have been in place for at most ∼400 years.
The Association Between Disease Activity and Duration in Systemic Sclerosis
Authors: WALKER JENNIFER G. , STEELE RUSSELL J. , SCHNITZER MIREILLE , TAILLEFER SUZANNE , BARON MURRAY ,   Canadian Scleroderma Research Group, HUDSON MARIE 
Published: September 2010

Objective.The absence of a standardized disease activity index has been an important barrier in systemic sclerosis (SSc) research. We applied the newly derived Valentini Scleroderma Disease Activity Index (SDAI) among our cohort of patients with SSc to document changes in disease activity over time and to assess possible differences in activity between limited and diffuse disease.Methods.Cross-sectional study of a national cohort of patients enrolled in the Canadian Scleroderma Research Group Registry. Disease activity was measured using the SDAI. Depression scores were measured using the Centre for Epidemiologic Studies Depression Scale (CES-D).Results.A total of 326 out of 639 patients had complete datasets at the time of this analysis; 87% were female, of mean age 55.6 years, with mean disease duration 14.1 years. SDAI declined steeply in the first 5 years after disease onset and patients with diffuse disease had 42% higher SDAI scores than patients with limited disease with the same disease duration and depression scores (standardized relative risk 1.42, 95% CI 1.21, 1.65). Patients with higher CES-D scores had higher SDAI scores relative to patients with the same disease duration and disease subset (standardized RR 1.22, 95% CI 1.14, 1.31). Among the 10 components that make up the SDAI, only skin score (standardized OR 0.59, 95% CI 0.43, 0.82) and patient-reported change in skin (standardized OR 0.64, 95% CI 0.45, 0.92) decreased with increasing disease duration. High skin scores (standardized OR 32.2, 95% CI 15.8, 72.0) were more likely and scleredema (standardized OR 0.58, 95% CI 0.37, 0.92) was less likely to be present in patients with diffuse disease. High depression scores were associated with positive responses for patient-reported changes in skin and cardiopulmonary function.Conclusion.Disease activity declined with time and patients with diffuse disease had consistently higher SDAI scores. Depression was found to be associated with higher patient activity scores and strongly associated with patient self-response questions. The role of depression should be carefully considered in future applications of the SDAI, particularly as several components of the score rely upon patient recall.
Ultrasonographic Measurements of Joint Cartilage Thickness in Healthy Children: Age- and Sex-Related Standard Reference Values
Authors: SPANNOW ANNE HELENE , PFEIFFER-JENSEN MOGENS , ANDERSEN NIELS T. , HERLIN TROELS , STENBØG ELISABETH 
Published: September 2010

Objective.Loss of joint cartilage may be an early feature of chronic inflammatory joint diseases like juvenile idiopathic arthritis (JIA). Conventional radiography usually detects only late changes such as joint space narrowing and bone erosion rather than early inflammatory changes. Joint cartilage is easily visualized with high-frequency ultrasonography (US), but age- and gender-related normal standard reference values should be established before US measurement of cartilage thickness becomes standard procedure in the clinic.Methods.A cross-sectional study of bilateral grey-scale US cartilage thickness of the knee, ankle, wrist, and second metacarpophalangeal (MCP) and second proximal interphalangeal (PIP) joints was performed in 394 (215 boys/179 girls) healthy Danish Caucasian children aged between 7 and 16 years.Results.Cartilage thickness differed significantly between sexes (p < 0.001 for all joints), boys having thicker cartilage than girls. Cartilage thickness clearly decreased with increasing age in both sexes. A formula for calculating sex-specific cartilage thickness at different ages in childhood is suggested. No difference between the right and left side of the investigated joints was observed.Conclusion.Using US, we established age- and sex-related normal reference intervals for cartilage thickness of the knee, ankle, wrist, and MCP and PIP joints in 7- to 16-year-old children, and designed a formula for calculating hyaline cartilage thickness in all age groups throughout childhood.
Increased Production of a Proliferation-inducing Ligand (APRIL) by Peripheral Blood Mononuclear Cells Is Associated with Antitopoisomerase I Antibody and More Severe Disease in Systemic Sclerosis
Authors: BIELECKI MAREK , KOWAL KRZYSZTOF , LAPINSKA ANNA , BERNATOWICZ PAWEL , CHYCZEWSKI LECH , KOWAL-BIELECKA OTYLIA 
Published: September 2010

Objective.A proliferation-inducing ligand (APRIL), a member of the tumor necrosis factor (TNF) family, plays a crucial role in the survival of peripheral B cells, and may contribute to the pathogenesis of systemic sclerosis (SSc) through upregulation of autoantibody production and maintenance of autoimmune phenomena. We evaluated the capacity of peripheral blood mononuclear cells from patients with SSc (SSc-PBMC) to produce APRIL; and investigated correlations between production of APRIL by SSc-PBMC and clinical and laboratory features of the disease.Methods.PBMC from 20 patients with SSc and 14 healthy subjects were incubated in fetal calf serum-supplemented RPMI medium. APRIL levels were determined in cell culture supernatants by ELISA.Results.PBMC from patients with SSc produced significantly more APRIL (961 ± 151 pg/ml/105cells) than control PBMC (798 ± 219 pg/ml/105cells; p < 0.01). In patients with SSc, increased production of APRIL was associated with the presence of diffuse skin involvement, scleroderma lung disease, peripheral vasculopathy, greater capillary damage on capillaroscopy, and presence of anti-topoisomerase I (anti-topo I) antibodies. Multivariate regression analysis revealed anti-topo I antibodies as the only independent predictor of high production of APRIL by PBMC.Conclusion.Production of APRIL is increased in SSc-PBMC and is associated with the presence of anti-topo I antibodies and more severe disease. Targeting the APRIL pathway might represent a therapeutic possibility for treatment of patients with SSc, in particular those with anti-topo I antibodies.
Un pragmatisme ambigu ? « L'en tant que » herméneutique au regard des Recherches philosophiques
Authors: Monod Jean-Claude 
Published: September 2010

Résumé Si l’on trouve dans Être et Temps comme dans les Recherches philosophiques un souci commun visant à rendre compte d’un rapport d’usage quotidien aux choses, que la tradition philosophique aurait eu tendance à méconnaître au profit de leur saisie « objective », cette similitude de surface est plutôt vue ici comme le point de départ d’une discussion : cette saisie pré-objective des choses doit-elle être approchée par une généralisation de l’idée d’interprétation-explicitation, ou bien faut-il maintenir une distinction forte entre « voir » et « voir comme » ?
Qui représentent les élus de la « diversité » ?
Authors: Avanza Martina 
Published: September 2010

Résumé À l’exception de l’extrême droite, tous les partis politiques disent aujourd’hui vouloir mieux représenter la « diversité » de la société française et ce, à travers l’augmentation d’élus de la « diversité ». Mais pourquoi cette nécessité apparaît-elle aujourd’hui comme une évidence ? S’agit-il de conquérir l’électorat que ces élus sont censés représenter ? Et quel électorat représentent-ils ? À l’inverse, si ces élus sont des élus comme les autres qui n’ont pas vocation à représenter un segment précis de l’électorat, s’agirait-il plutôt de défendre l’égalité d’accès aux fonctions ? Cet article explorera ces différents registres de légitimation. Le succès de la « diversité » étant en grande partie fondé sur le flou de cette catégorie, il s’agira de voir les usages qui en sont faits par les partis mais aussi par les élus ainsi labellisés, et ce, afin d’interroger ce qui se joue, via la « diversité », dans le lien entre représentants et représentés au sein d’un système républicain et universaliste a priori peu enclin à la représentation des minorités.
Latent Membrane Protein 1, the EBV-Encoded Oncogenic Mimic of CD40, Accelerates Autoimmunity in B6.Sle1 Mice
Authors: Peters Anna L. , Stunz Laura L. , Meyerholz David K. , Mohan Chandra , Bishop Gail A. 
Published: September 2010

Abstract
EBV infection is associated with development of the autoimmune disease systemic lupus erythematosus (SLE), and EBV can reactivate during SLE flares. Latent membrane protein 1 (LMP1) is an EBV-encoded oncogenic mimic of CD40 that can be re-expressed in PBMCs during SLE flares, as &gt;90% of humans are latently EBV-infected. Whether LMP1 signaling exacerbates SLE is unknown. The phenotype of mice expressing a chimeric molecule with the mouse CD40 extracellular domain and the LMP1 intracellular signaling regions (mCD40-LMP1 transgenic [tg]) includes enhanced autoreactivity, yet these mice do not develop fatal autoimmune disease. We hypothesized that LMP1-mediated activation signals cooperate with and/or amplify events that predispose individuals to development of autoimmunity. To determine which aspects of autoimmunity may be exacerbated by LMP1, we bred mCD40-LMP1tg mice to two lupus-prone strains, B6.Sle1 and B6.Sle3, and analyzed autoimmunity parameters. LMP1+Sle1+/+ mice developed enlarged lymphoid organs containing increased frequencies of germinal center, B cells, CD86+ B cells, and activated and memory T cells compared with non-tg littermates. Anti-histone Abs were elevated in serum of LMP1+Sle1+/+ mice, and they had signs of kidney pathology. LMP1+Sle1+/+ B cells produced increased IL-6 and upregulated CD86 to a higher degree following CD40 stimulation in vitro, suggesting that the in vivo autoimmune exacerbation is B cell intrinsic. In contrast, the LMP1 transgene has no additional effects on autoimmunity on the B6.Sle3 background. These data indicate that LMP1-induced effects can cooperate with distinct subsets of host genes that predispose to autoimmunity and can thus be an exacerbating factor in autoimmune disease via multiple mechanisms.
Surfactant Protein-A Inhibits Mycoplasma-Induced Dendritic Cell Maturation through Regulation of HMGB-1 Cytokine Activity
Authors: Ledford Julie G. , Lo Bernice , Kislan Michele M. , Thomas Joseph M. , Evans Katherine , Cain Derek W. , Kraft Monica , Williams Kristi L. , Wright Jo Rae 
Published: September 2010

Abstract
During pulmonary infections, a careful balance between activation of protective host defense mechanisms and potentially injurious inflammatory processes must be maintained. Surfactant protein A (SP-A) is an immune modulator that increases pathogen uptake and clearance by phagocytes while minimizing lung inflammation by limiting dendritic cell (DC) and T cell activation. Recent publications have shown that SP-A binds to and is bacteriostatic for Mycoplasma pneumoniae in vitro. In vivo, SP-A aids in maintenance of airway homeostasis during M. pneumoniae pulmonary infection by preventing an overzealous proinflammatory response mediated by TNF-α. Although SP-A was shown to inhibit maturation of DCs in vitro, the consequence of DC/SP-A interactions in vivo has not been elucidated. In this article, we show that the absence of SP-A during M. pneumoniae infection leads to increased numbers of mature DCs in the lung and draining lymph nodes during the acute phase of infection and, consequently, increased numbers of activated T and B cells during the course of infection. The findings that glycyrrhizin, a specific inhibitor of extracellular high-mobility group box-1 (HMGB-1) abrogated this effect and that SP-A inhibits HMGB-1 release from immune cells suggest that SP-A inhibits M. pneumoniae-induced DC maturation by regulating HMGB-1 cytokine activity.
The Class A Scavenger Receptor, Macrophage Receptor with Collagenous Structure, Is the Major Phagocytic Receptor for Clostridium sordellii Expressed by Human Decidual Macrophages
Authors: Thelen Tennille , Hao Yibai , Medeiros Alexandra I. , Curtis Jeffrey L. , Serezani Carlos H. , Kobzik Lester , Harris Lisa H. , Aronoff David M. 
Published: September 2010

Abstract
Clostridium sordellii is an emerging pathogen associated with highly lethal female reproductive tract infections following childbirth, abortion, or cervical instrumentation. Gaps in our understanding of the pathogenesis of C. sordellii infections present major challenges to the development of better preventive and therapeutic strategies against this problem. We sought to determine the mechanisms whereby uterine decidual macrophages phagocytose this bacterium and tested the hypothesis that human decidual macrophages use class A scavenger receptors to internalize unopsonized C. sordellii. In vitro phagocytosis assays with human decidual macrophages incubated with pharmacological inhibitors of class A scavenger receptors (fucoidan, polyinosinic acid, and dextran sulfate) revealed a role for these receptors in C. sordellii phagocytosis. Soluble macrophage receptor with collagenous structure (MARCO) receptor prevented C. sordellii internalization, suggesting that MARCO is an important class A scavenger receptor in decidual macrophage phagocytosis of this microbe. Peritoneal macrophages from MARCO-deficient mice, but not wild-type or scavenger receptor AI/II–deficient mice, showed impaired C. sordellii phagocytosis. MARCO-null mice were more susceptible to death from C. sordellii uterine infection than wild-type mice and exhibited impaired clearance of this bacterium from the infected uterus. Thus, MARCO is an important phagocytic receptor used by human and mouse macrophages to clear C. sordellii from the infected uterus.