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The protection strategy adopted for the European DEMOnstration (EU-DEMO) fusion power reactor foresees the use of sacrificial components–referred to as limiters–dealing with plasma-wall contacts. Their aim is to protect the first wall (FW) against the huge amount of plasma energy (up to GigaJoules) released in a few milliseconds during disruptive events, which might lead to melting and/or vaporization of the foreseen plasma-facing tungsten armor. The current limiter design concepts rely on actively water-cooled plasma-facing components (PFCs) made of tungsten. As water is not allowed inside the main chamber, limiter’s PFCs must be designed to preserve the cooling system integrity under any scenario, therefore the estimate of the thickness of material undergoing any phase change is crucial. Given the initial assessment of plasma magnetic configurations during off-normal events, this article describes the procedure followed for designing the limiter’s PFC, which includes a novel approach for estimating the molten thickness of material under high heat flux. A simplified 1-D model has been implemented in MATLAB, which deals with multiphase moving boundary problems, hence its name Thermal Analysis foR Tracking InterFaces under meLting&vaporizaTion-induced plasma Transient Events (TARTIFL&TTE). This model takes its inspiration from the way phase change interface tracking problems are tackled in food industry (i.e., freeze-drying processes) and solute concentration diffusion-controlled problems. It overcomes the complexity of solving a strongly coupled non-linear system of partial and ordinary differential equations in moving spatial domains by adopting a change of coordinate system based on the Landau transformation. As a result, an equivalent and fixed spatial coordinate system is defined where the spatial domain boundaries of the different phases are constrained, and the systems of governing equations are easy to solve. Both the solid and liquid phases are modeled, while the vapor is assumed to be removed once formed. Its benchmark against computational results found in the literature has shown a very good agreement, which paves the way to further development of it. For phase change interface tracking problems in 2-D/3-D and more complex geometries, a commercial Multiphysics software adopting the Lagrangian–Eulerian approach in moving mesh frames will be used for tackling problems where material is removed following a phase change. Although the vapor domain is not simulated, a set of gas kinetics boundary conditions couples the interface between vapor and liquid phases, driving its position over time. This will be detailed described in a future companion article.

Stem cells might provide unlimited supply of transplantable cells for β-cell replacement therapy in diabetes. The human limbus is a highly specialized region hosting a well-recognized population of epithelial stem cells, which sustain the continuous renewal of the cornea, and the recently identified stromal fibroblast-like stem cells (f-LSCs), with apparent broader plasticity. However, the lack of specific molecular markers for the identification of the multipotent limbal subpopulation has so far limited the investigation of their differentiation potential. In this study we show that the human limbus contains uncommitted cells that could be potentially harnessed for the treatment of diabetes. Fourteen limbal biopsies were obtained from patients undergoing surgery for ocular diseases not involving the conjunctiva or corneal surface. We identified a subpopulation of f-LSCs characterized by robust proliferative capacity, expressing several pluripotent stem cell markers and exhibiting self-renewal ability. We then demonstrated the potential of f-LSCs to differentiate in vitro into functional insulin-secreting cells by developing a four-step differentiation protocol that efficiently directed f-LSCs towards the pancreatic endocrine cell fate. The expression of specific endodermal, pancreatic, islet, and β-cell markers, as well as functional properties of f-LSC-derived insulin-producing cells, were evaluated during differentiation. With our stage-specific approach, up to 77% of f-LSCs eventually differentiated into cells expressing insulin (also assessed as C-peptide) and exhibited phenotypic features of mature β-cells, such as expression of critical transcription factors and presence of secretory granules. Although insulin content was about 160-fold lower than what observed in adult islets, differentiated cells processed ~98% of their proinsulin content, similar to mature β-cells. Moreover, they responded in vitro in a regulated manner to multiple secretory stimuli, including glucose. In conclusion, f-LSCs represent a possible relevant source of autologous, transplantable, insulin-producing cells that could be tested for the reversal of diabetes.

Objective: It is well known that hyperandrogenism and insulin-resistance with or without compensatory hyperinsulinism are closely associated, but the Rotterdam Consensus has concluded that principally obese women with polycystic ovary syndrome (PCOS) should be evaluated for the metabolic syndrome. Our aim was to study insulin sensitivity in PCOS women with hirsutism regardless of obesity.Methods: Clinical characteristics, sex hormones and fasting- and after OGTT-glycemia and insulinemia, homeostatic model of insulin resistance (HOMA IR), and Matsuda index of insulin sensitivity were analyzed in 130 women with PCOS. Hirsutism has been evaluated through the Ferriman–Gallwey (FG) map scoring system.Results: PCOS women with hirsutism (57.7% of participants) showed significant higher values of total testosterone levels (P= 0.016), free testosterone (P= 0.027), DHEA sulfate (P= 0.017), and Δ4androstenedione (P= 0.018). They had similar body mass index (BMI) (P= 0.073) and were significantly less insulin sensitive (P= 0.002) than those without hirsutism (42.3% of participants). In women with PCOS and hirsutism, there was a significant correlation between FG score and insulin-sensitivity indexes (HOMA IR, ρ = 0.33, P= 0.005; Matsuda index, ρ = −0.34, P= 0.003) but not with the androgen levels. Moreover, women with hirsutism showed a significantly greater insulin (P= 0.019), C-peptide (P= 0.002), and glucose (P= 0.024) areas under the curve (auc2h).Conclusions: Our study suggests that the increased responsiveness of the pilo-sebaceous unit to androgens seems to be influenced by insulin sensitivity and that insulin resistance should be assessed in all hirsute women with PCOS regardless of their BMI, as insulin resistance was found in hirsute women irrespective of whether they were overweight or obese.

Offers advice to therapists on how to achieve the meditative effects of massage. Amount of concentration required to perceive light emanating from the hands to provide the focus needed to turn massage into meditation; Zen tea ceremony meditation; Massaging the surfaces of hands. INSET: A job of service.

Dysregulation of apoptosis is associated with the pathogenesis of organ-specific autoimmune diseases, through altered target organ susceptibility. Apoptosis signaling pathways can be initiated through activation of death receptors such as Fas. A comparative analysis of the expression of Fas and FasL, the antiapoptotic molecule Bcl-2, and apoptosis in both thyrocytes and thyroid-infiltrating lymphocytes (TILs) from patients with either Graves' disease (GD) or Hashimoto's thyroiditis (HT) was performed. GD thyrocytes expressed less Fas than HT thyrocytes, whereas GD TILs had higher levels of Fas and FasL than HT TILs. GD thyrocytes expressed higher levels of Bcl-2 compared with HT thyrocytes. The opposite pattern was observed in GD (low Bcl-2) and HT (high Bcl-2) TILs. Consistently, thyrocyte apoptosis was marked in HT and poor in GD thyroids, and TIL apoptosis was marked in GD and poor in HT. Our findings suggest that in GD thyroid the regulation of FasFasLBcl-2 favors apoptosis of infiltrating lymphocytes. Moreover, the reduced levels of FasFasL and increased levels of Bcl-2 should favor thyrocyte survival and hypertrophy associated with stimulatory thyroid-stimulating hormone receptor antibodies. In contrast, the regulation of FasFasLBcl-2 expression in HT can promote thyrocyte apoptosis via homophylic Fas-FasL interactions, and a gradual reduction in thyrocyte numbers leading to hypothyroidism. Fas-mediated apoptosis may be a general mechanism of cell damage in destructive organ-specific autoimmunity.

Several mechanisms are probably involved in determining the evolution of autoimmune thyroid disease (AITD) towards either hypothyroidism and the clinical syndrome known as Hashimoto's thyroiditis (HT) or toward hyperthyroidism and the symptoms of Graves' disease (GD). To gain further insight into such mechanisms we performed an exhaustive comparative analysis of the expression of key molecules regulating cell death (Fas, Fas ligand FasL, Bcl-2) and apoptosis in both thyrocytes and thyroid infiltrating lymphocytes (TILs) from patients with either GD or HT. GD thyrocytes expressed less Fas/FasL than HT thyrocytes, whereas GD TILs had higher levels of Fas/FasL than HT TILs. GD thyrocytes expressed increased levels of the antiapoptotic molecule Bcl-2 compared to the low levels detected in HT thyrocytes. The opposite pattern was observed in GD (low Bcl-2) and HT (high Bcl-2) TILs. The patterns of apoptosis observed were consistent with the regulation of Fas, FasL, and Bcl-2 described above. Our findings suggest that in GD thyroid the regulation of Fas/FasL/Bcl2 favors apoptosis of infiltrating lymphocytes, possibly limiting their autoreactive potential and impairing their ability to mediate tissue damage. Moreover, the reduced levels of Fas/FasL and increased levels of Bcl-2 should favor thyrocyte survival and favor the thyrocyte hypertrophy associated with immunoglobulins stimulating the thyrotropin (TSH) receptor. In contrast, the regulation of Fas/FasL/Bcl2 expression in HT promotes thyrocyte apoptosis, tissue damage, and a gradual reduction in thyrocyte numbers leading to hypothyroidism. These findings help define key molecular mechanisms contributing to the clinical outcome of thyroid autoimmunity.

Thyroid follicular cells (TFC) abundantly express a variety of immunologically relevant surface molecules in Hashimoto's thyroiditis (HT), for example, MHC antigens and adhesion molecules such as ICAM-1. Cytokines produced by infiltrating type 1 helper and cytotoxic T cells are importantly involved in de novoexpression or up-regulation of such molecules. We recently demonstrated that TFC from HT patients almost invariably bear on their surface two additive functional molecules: FasApo1CD95, an important participant in apoptosis, and B7.1, a member of a family of "co-stimulatory" molecules that are crucial for efficient antigen presentation. To date, 12 out of 14 surgical HT thyroid specimens that we studied by immunohistochemistry showed B7.1-positive TFC, and all showed Fas-positive TFC, different from Graves' disease (GD) or nonautoimmune specimens. We have investigated the role of a number of cytokines (IL-1?, TNF-?, IL-4, IL-6, IL-10, IL-12, TGF-?1, IFN-?) in regulating B7.1 and Fas expression. The experiments were performed by immunofluorescence flow cytometry on TFC purified from nontoxic goiter specimens which were Fas- and B7.1-negative at baseline, and one B7.1Fas-positive HT specimen. IFN-? (500 UmL) and TNF-? (200 ngmL) were unable to induce de novoexpression of B7.1 or Fas on cultured TFC. At higher doses (2000 UmL and 800 ngmL, respectively), they were unable to induce B7.1, but potentiated the spontaneous expression of Fas. Type 2 cytokines (IL-4 and IL-10) were unable to induce Fas or B7.1 on TFC at all, or to down-regulate Fas or B7.1 when expressed. On the other hand, IL-1? was the only cytokine able to induce Fas expression on Fas-negative TFC at doses ranging from 100 to 1000 pgmL. Moreover, at a dose of 400 pgmL, it was also able to induce B7.1. We demonstrated by immunohistochemistry that IL-1? is abundantly present on HT thyroids, including follicular structures. It is conceivable that IFN-?, or other cytokines secreted by infiltrating T-lymphocytes, are able to promote IL-1? secretion by TFC. In conclusion, a crucial role of IL-1? in "destructive" organ-specific autoimmunity may be suggested both for the perpetuation of the autoimmune reaction (induction of efficient autoantigen presentation by TFC, via co-stimulatory molecules) and in induction of tissue damage via "suicide" FasFasL-mediated TFC interaction.

Triggering of CD95 (Fas/APO-1) cell surface receptors regulates the elimination of autoreactive T and B lymphocytes through a mechanism of cell suicide called apoptosis. Three different mutations involving CD95 or its ligand are responsible for induction of autoimmunity in susceptible mouse strains. To determine whether a defect involving the CD95 receptor is associated with human insulin-dependent diabetes mellitus (IDDM), we have studied the expression of CD95 on peripheral blood mononuclear cells from IDDM patients at different stages of the disease. Three-colour flow cytometry and mean fluorescence analysis showed that T and B lymphocytes from newly diagnosed IDDM and patients with long-standing disease, and subjects at high risk of developing the disease were highly defective in CD95 expression (p<0.001), whereas monocytes from all the groups studied expressed normal amounts of CD95 molecules on their cell surface. T-cell subset analysis showed that the impairment of CD95 expression in IDDM patients and high-risk subjects involved both CD3+CD4+(p<0.001) and CD3+CD8+cells (prange: <0.01–0.001), suggesting that this alteration concerns both helper and cytotoxic T cells. Moreover, after activation in vitro with anti-CD3 monoclonal antibody, T cells from newly diagnosed IDDM patients maintained a reduced CD95 expression during the entire cell culture period (24–72 h) in comparison to the control population (p<0.001). In conclusion, we found a reduced expression of the apoptosis-inducing CD95 receptor on T and B lymphocytes of individuals with clinical and preclinical IDDM. We hypothesize that this defective expression may impair the capacity of autoreactive lymphocytes to undergo CD95-mediated apoptosis, contributing to the lack of control on beta-cell specific B- and T-cell clones.

The bcl-2 gene product has been shown to regulate apoptotic cell death, and its dysregulation has been shown to induce several abnormalities in the immune system. No data exist regarding bcl-2 expression in autoimmune diseases, such as human insulin-dependent diabetes mellitus (IDDM). We investigated bcl-2 protein expression by testing T lymphocytes from 15 newly-diagnosed (<3 weeks) IDDM patients in comparison to 10 age-matched control subjects. The expression of bcl-2 on CD3+lymphocyte subsets was investigated after membrane permeabilization by two- or three-colour immunofluorescence. When the percentage and mean fluorescence intensity (MFI) of bcl-2+/CD3+cells from normal individuals and patients were compared, we found that bcl-2 expression within the CD3+and CD4+CD45R0+T-cell populations was reduced significantly in IDDM patients (46.8±15.4 vs 79.6±11.7; 25.7±3.8 vs 47.15±5.7, respectively; p<0.001). To establish whether low bcl-2 expression in T cells from newly-diagnosed patients reflects their susceptibility to death by an apoptotic process, we also evaluated DNA staining with propidium iodide in CD3+lymphocyte suspension after a (24–72 h) culture period (spontaneous apoptosis). We found that IDDM patients have higher levels of spontaneous apoptosis (mean±SEM: 24 h=4.6±0.8; 48 h=9.9±1; 72 h=12.8±1.1) than control subjects (24 h=1.8±0.4; 48 h=4.6±0.4; 72 h=5.7±0.3; p<0.02–0.001). Our study suggests that recent onset IDDM is characterised by reduced bcl-2 expression, which in turn may be associated with the increased spontaneous apoptosis we observed.

In Type I diabetes the observation of a decreased release of interleukin-2 (IL-2) and soluble IL-2 receptors by means of stimulated lymphocytesin vitro indicates that a primary immunoregulatory defect may be involved. To confirm this hypothesis we investigated the T-cell activation trend, evaluating the surface expression of IL-2 receptor (CD25), transferrin (CD71), HLA class II (DR), and CD69 phenotypes afterin vitro stimulation with phytohemagglutinin (PHA; 1 and 10 µg/ml) and concanavalin A (12.5 µg/ml) in six newly diagnosed Type I diabetics and six islet cell- and insulin autoantibody-positive first-degree relatives. As controls were studied six long-standing Type I diabetics and six healthy subjects. T-cell cultures from the four groups were performed on the same day and examined at 0, 24, 48, 96, 120, and 144 hr. Cytometric analysis was performed, keeping PBMC gating constant on the basis of physical parameters (scatter and volume). Using both PHA concentrations, a lower level of CD25, CD71, CD69, and DR antigen expression was found in newly diagnosed patients at all observation times with respect to control cultures (P<0.001). Unexpectedly, pre-Type I diabetic subjects, after 1 µg/ml of PHA, showed a significantly reduced expression of CD69 (P<0.001) and CD71 (P<0.001). The levels remained low, also with high PHA, at the different observation periods, while CD25 expression was found to be reduced in prediabetics only after 1 µg/ml of PHA (P<0.001). The long-standing patients showed a T cell activation trend very close to the latter. Our data show that in Type I diabetes and in the early phases of the disease, the initial activation signal(s) appears to be affected, particularly with one or more subsequent events necessary to initiate the appearance of “activation antigens.” This study suggests that the natural history of immunoregulation in pre-Type I and Type I diabetes is characterized by a primary defect in this system, which also persists in patients with long-standing disease.

No Abstract

Interferon (IFN)-γ, interleukin (IL)-10, IL-6, and tumor necrosis factor (TNF)-α were significantlyincreased in sera from Sicilian patients with acute boutonneuse fever (BF) compared with those ofhealthy controls. IFN-γ levels dropped sharply within the second week after infection. IL-6, IL-10,and TNF-α levels gradually declined; in convalescent patients only were they in the normal range.In contrast, peripheral blood mononuclear cells (PBMC) stimulated in vitro with phytohemagglutinin(PHA) produced low levelsof IL-10 and IFN-γ in acute BF that were compatible with the reductionin the levels of CD4+, CD4+/CD45RO+, and CD4+ICD45RA+ cells. In vitro production of TNF-α and IL-6 from PBMC stimulated with PHA was not significantly modified during the various phases of the infection compared with control PBMC, which could be due to the persistence of high levels of CD14+ monocytes compensating for the decrease in CD20+ B cells.

Sera and urine samples from 115 Sicilian patients with boutonneuse fever (BF), obtained at thetime of diagnosis and after clinical recovery, were analyzed for concentrations of interleukin (IL)-2 and soluble IL-2 receptor (sIL-2R). There were significantly high levels of sIL-2R in the urine and sera of patients with acute BF compared with healthy controls, and the values returned to normal following successful chemotherapy. The data indicate that the sIL-2R urine concentrations correlated directly with the sIL-2R sera levels. In contrast, in all tested sera and urine samples, IL-2 levels were normal. Furthermore, a reduction in IL-2 production by peripheral blood mononuclear cells from acute BF patients was also observed. sIL-2R represents an unspecific marker useful to monitor the evolution of BF.