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The work presents a research on preparation and physical and electrochemical characterisation of dc magnetron sputtered Pd films envisaged for application as hydrogen storage in a chip-integrated hydrogen microenergy system. The influence of the changes in the sputtering pressure on the surface structure, morphology, and roughness was analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AMF). The electrochemical activity towards hydrogen adsorption/desorption and formation of PdH were investigated in 0.5 M H2SO4 using the methods of cyclic voltammetry and galvanostatic polarisation. The changes in the electrical properties of the films as a function of the sputtering pressure and the level of hydrogenation were evaluated before and immediately after the electrochemical charging tests, using a four-probe technique. The research resulted in establishment of optimal sputter regime, ensuring fully reproducible Pd layers with highly developed surface, moderate porosity, and mechanical stability. Selected samples were integrated as hydrogen storage in a newly developed unitized microenergy system and tested in charging (water electrolysis) and discharging (fuel cell) operative mode at ambient conditions demonstrating a stable recycling performance.

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Polyomaviruses, including BK and JC viruses, have been associated with graft failure, but have not commonly been associated with malignancy. We present a case of renal cell carcinoma arising in an allograft kidney, in which the tumor and metastasis contain viral DNA. Tumor and biopsy specimens from this patient were examined with hematoxylin & eosin, immunohistochemistry (IHC) and in situ hybridization (ISH). The results were confirmed by real-time polymerase chain reaction (PCR) analysis with BKV primers. Other viruses including herpes simplex 1-2, cytomegalovirus (CMV), Epstein-Barr virus (EBV), and varicella zoster were not detected. The presence of BKV DNA in a renal cell carcinoma, including a metastatic focus, adds to the evidence that this virus may play a role in cancers of the kidney and urinary tract.

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BACKGROUND: Cytotoxic T-lymphocyte antigen 4 (CTLA4) has been shown to play a critical role in the down-regulation of the immune response. We retrospectively examined the association between acute rejection and two polymorphisms in the CTLA4 gene, the dinucleotide (AT)n repeat polymorphism in exon 3 and the single nucleotide polymorphism A/G at position 49 in exon 1, in a cohort of liver and kidney transplant recipients. METHODS AND RESULTS: A total of 207 liver and 167 renal transplant recipients were analyzed. In the case of the (AT)n repeat polymorphism we found an increased incidence of acute rejection in association with allele 3 and 4 in both liver and kidney (P=0.002 and 0.05, respectively). In addition, in liver transplant recipients, allele 7 was associated with acute rejection independent of ethnicity (P<0.05). Allele 1 was less frequently observed in African American as compared with Caucasian liver and kidney transplant recipients, with a frequency of 33.8% and 69%, respectively (P<0.0001). Those patients with allele 1 had a tendency toward a lower rate of rejection at 42% versus 57.8% (P=0.058), suggesting a potential protective effect of allele 1. Analysis of the A/G single nucleotide polymorphism demonstrated no association between either allele and the incidence of acute rejection in the patients studied. CONCLUSION: These initial observations provide the necessary basis to further investigate the risk stratification of transplant recipients based on specific CTLA4 gene polymorphisms.

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The changes in the immune status of the calves infected with bovine herpes virus-1 inducing infectious rhinotracheitis were studied. The virus was introduced by intratracheal inoculation of 5 cm3 suspension with minimal concentration of 10(-7) CPU50 per 1 cm2 from the Cervena voda strain cultivated in calf kidney culture. An infection of moderate seriousness and characteristic clinical manifestations was caused. On the 2nd, 5th, 10th and 15th day after the infection lung lavage was carried out and samples were taken from the peripheral blood. The number, viability and differential distribution of the alveolar macrophages and phagocytic and microbicidal ability showed a tendency to decrease during the acute phase of the infection (the 2nd-5th day) followed by a slow restoration in the period of convalescence (the 15th day). Some parameters of the systemic immunity--number of the plaque-forming and the rosette-forming cells, differential and absolute number of leucocytes in the peripheral blood--also had similar dynamics. The changes in the local and in the systemic, in the cell and humoral immunity were connected to the pathogenesis of the infection and the immune suppressive properties of the agent. The rhinotracheitis infection is indicative of the character of changes in the immune status at herpes virus infections and, on the other hand, it can be used as a model for testing immunostimulators of recovery effect.

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The immunomodulating effect on mice of three products glucomacropeptides obtained from whey with different carbohydrate and peptide components has been studied. After the preliminary application of the preparations at several doses the protective effect in infections with Salmonella typhimurium and Klebsiella pneumoniae increases to different extent. At lower doses fraction 3 increases in vitro the mitogen-induced proliferation of the thymus cells. The phagocytosis of the polymorphonuclear cells on the 24th hour after application of the three preparations is activated. The influence of the structurally different fractions on the immunoprotective effect is discussed.

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The stimulating properties of three fractions of a glucomacropeptide consisting of different carbohydrate and peptide components were studied. The phagocytic activity of polymorphonuclears was increased on the 24th hour and of macrophages on the 3rd day after application of the preparations to mice. In vitro fraction 3 stimulates the lysozyme activity and the synthesis of proteins and Clq of the macrophages complement. These properties of the cells are collaborated by the established ultrastructural changes. The different composition of the fractions determines their immunostimulating effect.

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