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The correct derivation of paleotemperatures from ice cores requires exact knowledge of all processes involved before and after the deposition of snow and the subsequent formation of ice. At the Antarctic deep ice core drilling site Dome C, a unique data set of daily precipitation amount, type, and stable water isotope ratios is available that enables us to study in detail atmospheric processes that influence the stable water isotope ratio of precipitation. Meteorological data from both automatic weather station and a mesoscale atmospheric model were used to investigate how different atmospheric flow patterns determine the precipitation parameters. A classification of synoptic situations that cause precipitation at Dome C was established and, together with back-trajectory calculations, was utilized to estimate moisture source areas. With the resulting source area conditions (wind speed, sea surface temperature, and relative humidity) as input, the precipitation stable isotopic composition was modeled using the so-called Mixed Cloud Isotope Model (MCIM). The model generally underestimates the depletion of 18O in precipitation, which was not improved by using condensation temperature rather than inversion temperature. Contrary to the assumption widely used in ice core studies, a more northern moisture source does not necessarily mean stronger isotopic fractionation. This is due to the fact that snowfall events at Dome C are often associated with warm air advection due to amplification of planetary waves, which considerably increases the site temperature and thus reduces the temperature difference between source area and deposition site. In addition, no correlation was found between relative humidity at the moisture source and the deuterium excess in precipitation. The significant difference in the isotopic signal of hoarfrost and diamond dust was shown to disappear after removal of seasonality. This study confirms the results of an earlier study carried out at Dome Fuji with a shorter data set using the same methods.

Past temperature reconstructions from Antarctic ice cores require a good quantification and understanding of the relationship between snow isotopic composition and 2 m air or inversion (condensation) temperature. Here, we focus on the French–Italian Concordia Station, central East Antarctic plateau, where the European Project for Ice Coring in Antarctica (EPICA) Dome C ice cores were drilled. We provide a multi-year record of daily precipitation types identified from crystal morphologies, daily precipitation amounts and isotopic composition. Our sampling period (2008–2010) encompasses a warmer year (2009, +1.2 °C with respect to 2 m air temperature long-term average 1996–2010), with larger total precipitation and snowfall amounts (14 and 76 % above sampling period average, respectively), and a colder and drier year (2010, −1.8 °C, 4 % below long-term and sampling period averages, respectively) with larger diamond dust amounts (49 % above sampling period average). Relationships between local meteorological data and precipitation isotopic composition are investigated at daily, monthly and inter-annual scale, and for the different types of precipitation. Water stable isotopes are more closely related to 2 m air temperature than to inversion temperature at all timescales (e.g. R2 = 0.63 and 0.44, respectively for daily values). The slope of the temporal relationship between daily δ18O and 2 m air temperature is approximately 2 times smaller (0.49 ‰ °C−1) than the average Antarctic spatial (0.8 ‰ °C−1) relationship initially used for the interpretation of EPICA Dome C records. In accordance with results from precipitation monitoring at Vostok and Dome F, deuterium excess is anti-correlated with δ18O at daily and monthly scales, reaching maximum values in winter. Hoar frost precipitation samples have a specific fingerprint with more depleted δ18O (about 5 ‰ below average) and higher deuterium excess (about 8 ‰ above average) values than other precipitation types. These datasets provide a basis for comparison with shallow ice core records, to investigate post-deposition effects. A preliminary comparison between observations and precipitation from the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis and the simulated water stable isotopes from the Laboratoire de Météorologie Dynamique Zoom atmospheric general circulation model (LMDZiso) shows that models do correctly capture the amount of precipitation as well as more than 50 % of the variance of the observed δ18O, driven by large-scale weather patterns. Despite a warm bias and an underestimation of the variance in water stable isotopes, LMDZiso correctly captures these relationships between δ18O, 2 m air temperature and deuterium excess. Our dataset is therefore available for further in-depth model evaluation at the synoptic scale.

At the East Antarctic deep ice core drilling site Dome C, daily precipitation measurements were initiated in 2006 and are being continued until today. The amounts and stable isotope ratios of the precipitation samples as well as crystal types are determined. Within the measuring period, the two years 2009 and 2010 showed striking contrasting temperature and precipitation anomalies, particularly in the winter seasons. The reasons for these anomalies are analysed using data from the mesoscale atmospheric model WRF (Weather Research and Forecasting Model) run under the Antarctic Mesoscale Prediction System (AMPS). 2009 was relatively warm and moist due to frequent warm air intrusions connected to amplification of Rossby waves in the circumpolar westerlies, whereas the winter of 2010 was extremely dry and cold. It is shown that while in 2010 a strong zonal atmospheric flow was dominant, in 2009 an enhanced meridional flow prevailed, which increased the meridional transport of heat and moisture onto the East Antarctic plateau and led to a number of high-precipitation/warming events at Dome C. This was also evident in a positive (negative) SAM (Southern Annular Mode) index and a negative (positive) ZW3 (zonal wave number three) index during the winter months of 2010 (2009). Changes in the frequency or seasonality of such event-type precipitation can lead to a strong bias in the air temperature derived from stable water isotopes in ice cores.

Antarctic surface snow has been studied by means of continuous measurements and observations over a period of 3 yr at Dome C. Snow observations include solid deposits in form of precipitation, diamond dust, or hoar, snow temperatures at several depths, records of deposition and erosion on the surface, and snow profiles. Together with meteorological data from automatic weather stations, this forms a unique dataset of snow conditions on the Antarctic Plateau. Large differences in snow amounts and density exist between solid deposits measured 1 m above the surface and deposition at the surface. We used the snow-cover model SNOWPACK to simulate the snow-cover evolution for different deposition parameterizations. The main adaptation of the model described here is a new event-driven deposition scheme. The scheme assumes that snow is added to the snow cover permanently only during periods of strong winds. This assumption followed from the comparison between observations of solid deposits and daily records of changes in snow height: solid deposits could be observed on tables 1 m above the surface on 94 out of 235 days (40%) while deposition at the surface occurred on 59 days (25%) during the same period, but both happened concurrently on 33 days (14%) only. This confirms that precipitation is not necessarily the driving force behind non-temporary snow height changes. A comparison of simulated snow height to stake farm measurements over 3 yr showed that we underestimate the total accumulation by at least 33%, when the total snow deposition is constrained by the measurements of solid deposits on tables 1 m above the surface. During shorter time periods, however, we may miss over 50% of the deposited mass. This suggests that the solid deposits measured above the surface and used to drive the model, even though comparable to ECMWF forecasts in its total magnitude, should be seen as a lower boundary. As a result of the new deposition mechanism, we found a good agreement between model results and measurements of snow temperatures and recorded snow profiles. In spite of the underestimated deposition, the results thus suggest that we can obtain quite realistic simulations of the Antarctic snow cover by the introduction of event-driven snow deposition.

We have previously reported that serum levels of soluble HLA-A, -B, -C and -G antigens are elevated in HIV-infected subjects and decrease after antiretroviral theraphy. In this study we measured soluble HLA-G serum levels in patients with AIDIS affected by different AIDIS-defining conditions before and during antiretroviral therapy and correlated them with virological and immunological parameters. Soluble HLA-G levels were significantly higher in AIDIS patients before treatment as compared to healthy controls and signifacantly decreased after 36 months of theraphy, correlating with the decrease of plasma HIV-RNA level and CD8+ T-lymphocytes number and with the increase of CD4+ T-lymphocytes number. Soluble HLA-G levels were significantly higher in patients with opportunistic infections and Kaposi's sarcoma as compared with those with wasting syndrome. These data suggest that infections and neoplasms may trigger the shedding of soluble HLA-G in serum might represent a surrogate marker to monitor virological response and immune reconstitution in HIV-positive subjects.

Aim. Human major histocompatibility complex class I antigens (HLA-A, -B, and -C) are heterodimetric molecules composed of a heavy chain non covalently associated with an invariant protein known as B2-microglobulin. Besides being expressed on the membrane of the large majority of nucleated cells, HLA class I antigens are found in serum (sHLA-I). We have previously detected a significant increase in the serum level of B2-microglobulin-associated HLA-I antigens in HIV-infected patients as compared to HIV-negative controls. Materials and methods. The introduction of the Highly Active Antiretroviral Theraphy (HAART) has modified the clinical course of the disease and decreased the AIDS-related morbidity and mortality. Therefore, we measured the levels of sHLA-I antigens in 64 HIV-infected patients before and during HAART treatment and correlated them with the imunological and virological response to the antiretroviral treatment. Result and conclusions. Serum sHLA-I antigen level was elevaed in all HIV-infected subjects before and significantly decreased after 36 months of HAART treatment correlated with the decrease of plasma HIV-RNA level and with the increased od CD4+ T-lymphocyte number. These results suggest that the measurement of sHLA-I antigens serum level might represent a useful surrogate marker to monitor HIV-positive subjects undergoing HAART treatment.

Objectives: During the last decade many new biological immune modulators have entered the market as new therapeutic principles. Tumor necrosis factor (TNF)-α is a pro-inflammatory cytokine known to a have a key role in the pathogenic mechanisms of various immune-mediated or inflammatory diseases. However, TNF-α also plays a key role in endothelial dysfunction and, thus, in the development and progression of atherosclerosis. What, then, is the potential therapeutic role of TNF-α inhibitors?, Methods: We analysed the current literature concerning the administration of TNF-α inhibitors and their potential benefits upon endothelial function., Results: TNF-α inhibitors decrease the serum levels of inflammatory markers such as TNF-α itself, CRP, IL-6, and increased the tissue expression of endothelial NO synthase and the vasodilatory response to bradykinin., Discussion: TNF-α inhibitors may change the progression of endothelial dysfunction and, thus, slow down the atherosclerotic process.

Rheumatic autoimmune diseases have been associated with accelerated atherosclerosis and various types of vasculopathies. Atherosclerosis is an inflammatory condition which starts as a "response to injury" favoring endothelial dysfunction which is associated with increased expression of adhesion molecules, pro-inflammatory cytokines, pro-thrombotic factors, oxidative stress upregulation and abnormal vascular tone modulation. Endothelial dysfunction in rheumatic autoimmune diseases involves innate immune responses, including macrophages and dendritic cells expression of scavenger and toll-like receptors for modified or native LDL as well as neutrophil and complement activation, and dysregulation of adaptive immune responses, including proliferation of autoreactive T-helper-1 lymphocytes and defective function of dendritic and regulatory T cells. Specific differences for endothelial function among different disorders include: a) increased amounts of pro-atherogenic hormones, decreased amounts of anti-atherogenic hormones and increased insulin resistance in rheumatoid arthritis; b) autoantibodies production in systemic lupus erythematosus and antiphospholipid syndrome; c) smooth muscle cells proliferation, destruction of internal elastic lamina, fibrosis and coagulation and fibrinolytic system dysfunction in systemic sclerosis. Several self-antigens (i.e. high density lipoproteins, heat shock proteins, β2-glycoprotein1) and self-molecules modified by oxidative events (i.e. low density lipoproteins and oxidized hemoglobin) have been identified as targets of autoimmune responses. Endothelial dysfunction leads to accelerated atherosclerosis in rheumatoid arthritis, systemic lupus erythematosus and spondyloarthropaties whereas obliterative vasculopathy is associated with systemic sclerosis. In this paper, we will briefly review the most relevant information upon endothelial dysfunction and inflammatory mechanisms in atherosclerosis and we will summarize the similarities and differences in vascular disease patterns underlying different rheumatic autoimmune diseases., (Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.)

Lymphedema is a chronic, progressive, and often debilitating condition. Primary lymphedema is a lymphatic malformation developing during the later stage of lymphangiogenesis. Secondary lymphedema is the result of obstruction or disruption of the lymphatic system, which can occur as a consequence of tumors, surgery, trauma, infection, inflammation, and radiation therapy. In this review, we report an update upon the diagnostic approach and the medical and surgical therapy for both primary and secondary lymphedema., (Copyright © 2012 Elsevier Inc. All rights reserved.)

We have previously reported that the serum levels of soluble human leukocyte antigen (HLA)-A, -B, -C, and -G antigens are elevated in human immunodeficiency virus (HIV)-infected subjects and decrease after antiretroviral therapy. In this study, we measured soluble HLA-G serum levels in patients with acquired immune deficiency syndrome (AIDS) affected by different AIDS-defining conditions before and during antiretroviral therapy and correlated them with virologic and immunologic parameters of response to treatment. Soluble HLA-G levels were significantly higher in AIDS patients before treatment as compared with healthy controls and significantly decreased after 36 months of therapy. The decrease of soluble HLA-G correlated with the decrease of plasma HIV-RNA level and CD8(+) T-lymphocytes number and with the increase of CD4(+) T-lymphocytes number. Soluble HLA-G levels were significantly higher in patients with opportunistic infections and Kaposi's sarcoma compared with patients with the wasting syndrome. These data suggest that infections and neoplasms may trigger the shedding of soluble HLA-G molecules, and confirm that the level of soluble HLA-G in serum might represent a surrogate marker to monitor virologic response and immune reconstitution in HIV-positive individuals., (Copyright © 2011 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)

We have reported that serum level of soluble HLA-A, -B, -C (sHLA-A,-B,-C) antigens is elevated in HIV-infected subjects and decreases after antiretroviral therapy (HAART). In this study, we measured the levels of soluble HLA-G (sHLA-G) antigens in a cohort of HIV-infected patients before and during HAART. sHLA-G and sHLA-A, -B, -C levels were significantly elevated in HIV-infected subjects as compared with controls before antiretroviral treatment and significantly decreased after 36 months of HAART. sHLA-G levels were correlated with sHLA-A, -B, -C levels, the decrease of plasma HIV-RNA level, the increase of CD4+ T-lymphocyte number and the decrease of CD8+ T-lymphocyte number. These results suggest that the measurement of sHLA-G and sHLA-A, -B, -C antigen serum levels might represent a useful surrogate marker to monitor virological response and immune reconstitution in HIV-positive subjects undergoing HAART treatment.

Human major histocompatibility complex class I antigens (HLA-A, -B, and -C) are heterodimeric molecules composed of a alpha heavy chain noncovalently associated with an invariant protein known as beta(2)-microglobulin. Beside being expressed on the membrane of the large majority of nucleated cells, HLA class I antigens are evident in serum (sHLA-I). We have previously detected a significant increase in the serum level of beta(2)-microglobulin-associated HLA-I antigens in human immunodeficiency virus (HIV)-infected patients compared with HIV-negative controls. The introduction of highly active antiretroviral therapy (HAART) modified the clinical course of the disease and decreased the acquired immunodeficiency syndrome-related morbidity and mortality. Therefore, we measured the levels of sHLA-I antigens in 64 HIV-infected patients before and during HAART treatment and correlated them with the immunological and virological response to antiretroviral treatment. Serum sHLA-I antigen level was elevated in all HIV-infected patients before and significantly decreased after 36 months of HAART treatment, correlating with the decrease of plasma HIV-RNA level and with the increase of CD4+ T-lymphocyte number. These results suggest that the measurement of sHLA-I antigens serum level might represent a useful surrogate marker to monitor HIV-positive patients undergoing HAART treatment.