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Familial paraganglioma is a dominantly inherited disorder characterised by the development of highly vascular tumours in the head and neck. Recently, a relationship between hereditary tumours derived from the autonomic nervous system and germline mutations in the gene encoding succinate dehydrogenase complex subunit D (SDHD) is increasingly a subject of study. Familial paraganglioma syndrome is embryologically related to phaeochromocytoma, another neuroendocrine tumour that shows great aetiological and genetic heterogeneity. Some hereditary phaeochromocytomas may be associated with germline mutations in VHL, RET and NF1 genes in genetic disorders such as yon Hippel-Lindau disease (VHL), multiple endocrine neoplasia type 2 (MEN 2) and neurofibromatosis type 1 (NF 1), respectively. However, there are many cases that cannot be explained by mutations in these genes. In this report, we describe two previously unreported mutations in two patients from 25 unrelated kindreds with phaeochromocytoma and/or paraganglioma disorders and with or without familial antecedents: a mutation featuring the change of tryptophan to a termination codon in exon 2, and a 4-bp deletion in exon 4 that results in a truncated protein. We also describe one missense substitution of uncertain significance. The patients had previously tested negative for germline mutations in VHL and RET genes and had not been previously selected. The involvement of SDHD mutations in familial phaeochromocytoma and/or paraganglioma predisposition is of considerable interest since other studies have shown these alterations to be associated with highly expressed angiogenic factors. [ABSTRACT FROM AUTHOR]

Abstract: Background: There is no consensus about the impact of thresholds of complement-fixing antibody assays. Recently, a C1q-SAB assay has been developed to identify complement-fixing HLA antibodies with high sensitivity and specificity. Our aim was to determine the correlation between IgG single antigens beads (SAB) and C1q-SAB assay results among patients on the renal waiting list. Patients and Methods: Serum samples from immunized renal waiting list patients as well as negative and positive controls were valided by Luminex (LMX). These sera, which were positive for 166 antibody specificities, were tested for HLA class I in parallel by LMX-IgG and LMX-C1q. Results: Comparison of antibody detection revealed no correlation based on median fluorescent intensity (MFI), levels between the IgG SAB and the C1qSAB assay (P > .05). IgG-positive sera with MFIs as low as 700 were able to fix C1q, whereas other sera with MFIs as high 14,500 did not. Furthermore, there appeared to be disparities in the profiles of class I antigens able to fix C1q-SAB. In our series, only 34% class I IgG SAB antibodies were also C1qSAB+. In several patients, we detected C1qSAB+ against IgGSAB- that was surely due to IgM antibodies. So, the C1qSAB assay detected IgM antibodies that fix complement. Conclusion: These data suggested that the C1q-SAB assay could be an important method to evaluate pretransplant virtual crossmatch and to define nonpermitted specificities (C1q-fixing) in kidney transplantation. [Copyright &y& Elsevier]

Abstract: A Reset observer (ReO) is a novel sort of observer consisting of an integrator, and a reset law that resets the output of the integrator depending on a predefined switching condition. For SISO systems, the switching condition is defined in such a manner that the ReO is reset when the output estimation error and the reset term have different sign. However, the way to define the reset condition to deal with MIMO systems has not been analyzed previously. As contributions, we provide a formulation to handle ReO for MIMO systems, and an algorithm to compute its gain for performance purposes. Additionally, the effectiveness of our proposed MIMO ReO is analyzed by simulations. [Copyright &y& Elsevier]

The problem of group delay distortion in last generation LFM radars has been identified as an important handicap for the development of high performance broadband systems. A simple digital calibration technique is now proposed to overcome this problem. Although it has been developed for pulsed synthetic aperture radars it can be easily applied to other LFM systems. [ABSTRACT FROM AUTHOR]

A closed-form solution is derived for the equivalent impedance of a planar winding with cylindrical symmetry placed between two half-spaces. This is basically the structure of a domestic induction heating appliance comprised of a planar winding, a metallic vessel, and a lossless magnetic substrate. The first matter addressed is the impedance of a sandwiched single-turn coil, obtained by using the vector potential Helmholtz equation solution, and the result is generalized to n-turn coils. The real part of this impedance represents power dissipated in the form of heat. The proposed model includes geometry dependence, frequency of excitation currents, and electromagnetic properties of both top and bottom media. Enhancement of power dissipation in the conducting media as a result of the inclusion of a magnetic substrate is also explored. Experimental results are presented in order to validate the theoretical model. [ABSTRACT FROM AUTHOR]

The design of domestic cooking stoves is usually optimized by performing time-consuming cooking experiments, often using frying of pancakes as a standard. Simulation of cooking processes may reduce the number of experiments used in the development of the cooking stoves, saving time and resources. In this work we propose a model of contact frying of pancakes in domestic cookers, particularly in induction hobs and radiant cookers, in which the heating of the cooking vessels can be non-uniform. This non-uniformity is unavoidable in practice, but it can be reduced by optimizing the design of the cooker. The proposed model combines heat and mass transfer phenomena, and also includes the correlation between the browning development and the temperature distribution, the local water content and the cooking time. The model has been also validated through experiments using a commercial induction hob and a radiation stove. With this model the color of the cooked pancakes can be predicted, taking into account also uneven heating, and through simulations the design of the cooker can be improved. [ABSTRACT FROM AUTHOR]

This work focuses on determining the switching limits in temperature for Reverse Conducting IGBTs and compares them to “conventional” IGBTs based on Trench technologies, all them belonging to 600 V–50 A application scenario. After, their leakage current under blocking state is tested at several working temperatures, in order to study the leakage current that limits the blocking safe operating area with temperature. Next, overcurrent tests have been performed. This investigation deals with understanding the overcurrent induced failures due to thermal effects using short circuit tests adapted to our needs. As a result, we observe that RC-IGBTs integrating a free-wheeling diode show the highest leakage losses in blocking state, whereas it presents the best ruggedness under short circuit tests. [ABSTRACT FROM AUTHOR]

Background Acute rejection (AR) remains a significant cause of graft loss. Better approaches to predict AR are being investigated. Surface CD28 protein is essential for T-cell proliferation and survival as well as cytokine production. Patients and Methods Pretransplant CD4 + CD28 + peripheral T cells were examined in 30 liver recipients (LRs) and 31 kidney recipients (KRs) by flow cytometry. Results Pretransplant CD4 + CD28 + T cells in LRs were significantly lower in rejectors than nonrejectors ( P = .002). Furthermore, the total number of CD28 molecules per cell in LRs ( P = .02) as well as KRs ( P = .047) was significantly lower in rejectors than nonrejectors. The healthy group did not display differences when compared with patients with end-stage liver disease or renal failure; however, stratification analysis displayed higher levels of CD4 + CD28 + when compared with rejected LRs ( P = .04) but not KRs. CD28 levels <41.94% were able to discriminate LRs at high risk of AR ( P = .003). Similarly, a total number of CD28 molecules ≤8359 ( P = .031) in LRs and ≤7669 ( P = .046) in KRs correlated with high risk of AR. Conclusion The preliminary results presented herein exhibit a fast and noninvasive method that assists clinicians to prevent AR by monitoring CD4 + CD28 + peripheral T cells. [ABSTRACT FROM AUTHOR]

: ObjectiveThe objective of this study is to assess a Simulect (basiliximab) regimen in routine clinical practice in the Spanish kidney transplantation units to evaluate efficacy and safety.: MethodsIn this prospective, observational study, data on demographics, parameters of efficacy, and safety in patients who under with kidney transplantation treated with Simulect (basiliximab) were collected through an on-line collection system.: ResultsOne hundred sixty three patients at 18 kidney transplant units included 12 months follow-up. The patient mean age was 52 years (DS 13,67) including 96 (58.90%) men and 67 (41.10%) women. Cold ischemia time was 19 hours (DS 6,79). Only 2 patients presented with PRA >50%. For prophylactic immunosuppression, 67.13% of patients received triple therapy with CNI (cyclosporine 49.65% or tacrolimus 17.48%), MMF (66.43%) or AZA (10.49%), and steroids. Incidence of acute rejection (AR) at 12 months was 12.27% (1.84% steroid-resistant). In subgroup analysis, AR was 13.5% in nondiabetics and 4.5% in diabetics, including 3 steroid-resistant episodes (1.84%) in nondiabetics and none in diabetics. In relation to donor age, AR was incidence 10.3% in patients with kidneys from donors aged 50 years or younger and 10.6% when donors were older than 50 years, including 1 (1.73%) and 2 (1.93%) steroid-resistant episodes, respectively. The graft and patient survival rates at 12 months were 90% and 98%, respectively.: ConclusionsSimulect (basiliximab) used in routine clinical practice provided good prophylaxis against acute rejection in several kidney transplant patient populations, similar to that observed in randomized clinical studies with excellent tolerability and safety. [Copyright &y& Elsevier]

Abstract: A significant relationship between hematocrit values and serum parameters such as the insulin like growth factor (IGF-1) and calcium was observed in patients with posttransplant erythrocytosis (PTE). Since angiotensin-converting enzyme inhibitors (ACEI) decrease hematocrit (Ht) levels in these patients, ACE genotype should play an important role. We designed this study to investigate whether ACE genotype or baseline concentrations of IGF-1, IGF-blood binding protein 3 (BP3), growth hormone (GH), or Ca influenced the response of Ht to ACEI treatment. Twenty-one kidney graft recipients with PTE were treated with enalapril (2.5 to 5 mg/d) for 1 year. IGF-1, BP3, GH, Ca, and Ht were determined before as well as 15, 30, 90, 180, and 365 days after enalapril treatment. ACE polymorphism was also determined. Enalapril treatment significantly decreased Ht levels. Only IGF-1 baseline levels showed a positive correlation to the decreased Ht (P < .025). ACE genotype as determined in 18 patients, showed no correlation with the response to enalapril. Patients with ACE genotype II showed a tendency to an earlier display of PTE. We conclude that low doses of enalapril decrease Ht levels in PTE patients; that PTE begins earlier in patients with II ACE genotype; and that only IGF-1 baseline levels influence the Ht decrease after treatment. These observations suggest that ACEI decrease the Ht via an inhibitory effect on IGF-1, which has a stimulary effect on erythropoiesis. [Copyright &y& Elsevier]