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Eu3+ complex with 1-(2,6-dihydroxyphenyl)ethanone in the solid state has been synthesized and characterized by elemental analysis, UV-visible, FT-IR and FT-Raman spectroscopies, powder X-ray diffraction, electron emission under femtosecond laser excitation. The stoichiometry and the formula of the studied complex have been proposed. Its physicochemical properties have been analyzed in terms of the structure and DFT calculations performed for the ligand. The luminescence and dynamics of the excited states depopulation have been studied using femtosecond laser excitation. Spectral and energetic transformation of femtosecond light impulses has been studied and possibility of the energy transfer between the ligand and the Eu3+ electron levels has been analyzed.

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The electron absorption and emission spectra were measured for the pyramidal LnPc(OAc) complexes in the solid state and co-doped in silica glass, where Ln=Er, Eu and Ho. The theoretical electron spectra were determined from the quantum chemical DFT calculation using four approximations CAM-B3LYP/LANL2DZ, CAM-B3LYP/CC-PVDZ, B3LYP/LANL2DZ and B3LYP/CC-PVDZ. It was shown that the best agreement between the calculated and experimental structural parameters and spectroscopic data was reached for the CAM-B3LYP/LANL2DZ model. The emission spectra were measured using the excitations both in the ligand and lanthanide absorption ranges. The possibility of energy transfer between the phthalocyanine ligand and excited states of lanthanide ions was discussed. It was shown that the back energy transfer from metal states to phthalocyanine state is responsible for the observed emission of the studied complexes both in the polycrystalline state and silica glass.

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Luminescence phenomena following femtosecond pulse excitation in UV and IR of Ce(3+) + Sm(3+) and Ce(3+) + Dy(3+) systems in Lu(2)SiO(5) - Gd(2)SiO(5) single crystals are investigated. Effect of excitation wavelength in the UV on Ce(3+) luminescence is interpreted assuming selective excitation of weakly interacting Ce1 and Ce2 sites. IR-excited up-converted spectra differ as compared to UV-excited spectra in that the contribution of Sm(3+) or Dy(3+) luminescence is higher and the Ce(3+) luminescence originates essentially in Ce1 sites. It has been concluded that excitation mechanism of up-conversion involves energy transfer from free electrons created in conduction band of the host.

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We report an efficient room-temperature operation of a resonantly pumped Er3+:GdVO4 laser at 1598.5 nm. The maximum continuous wave (CW) output power of 3.5 W with slope efficiency of 56% was achieved with resonant pumping by an Er-fiber laser at 1538.6 nm. With pumping by a commercial laser diode bar stack, a quasi-CW (QCW) output of 7.7 W and maximum slope efficiency of ~53% versus absorbed pump power were obtained. This is believed to be the first resonantly (in-band) pumped, room-temperature Er3+:GdVO4 laser.

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We report a highly efficient cryo-cooled eye-safe laser operation of a resonantly-pumped (in-band) Er³âº:GdVO4 single crystal. The maximum continuous wave (CW) power of 10.3 W with 84% slope efficiency was achieved at 1598.7 with pumping at 1538.6 nm by a spectrally-narrowed Er-fiber laser. Under the 1529 nm resonant pumping by a commercially available diode bar stack operating in a quasi-CW (QCW) mode, the laser delivered 37 W of output power with 68% slope efficiency. This is believed to be the first reported cryo-cooled Er³âº:GdVO4 laser, resonantly-pumped into the 4I15/2 →4I13/2 transition.

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Nearly quantum-defect-limited laser operation of a resonantly pumped Er(3+):YVO4 at 1593.5 nm is demonstrated. Maximum slope efficiency of ~85% and true CW power of ~13 W at 1593.5 nm were achieved with a beam propagation factor of M2 ~ 1.05. This slope efficiency is, to the best of our knowledge, the highest efficiency ever reported for a crystalline Er-doped laser.

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Correlation between structure and optical properties of rare earth ions in lead borate glasses and glass-ceramics was evidenced by X-ray-diffraction, Raman, FT-IR and luminescence spectroscopy. The rare earths were limited to Eu(3+) and Er(3+) ions. The observed BO(3)↔BO(4) conversion strongly depends on the relative PbO/B(2)O(3) ratios in glass composition, giving important contribution to the luminescence intensities associated to (5)D(0)-(7)F(2) and (5)D(0)-(7)F(1) transitions of Eu(3+). The near-infrared luminescence and up-conversion spectra for Er(3+) ions in lead borate glasses before and after heat treatment were measured. The more intense and narrowing luminescence lines suggest partial incorporation of Er(3+) ions into the orthorhombic PbF(2) crystalline phase, which was identified using X-ray diffraction analysis.

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Percutaneous coronary intervention (PCI) has revolutionized the management of and outcomes in patients with ST-segment elevation myocardial infarction (STEMI). The role of insulin-like growth factor-I (IGF-I) and tumor necrosis factor-alpha (TNF-alpha) in restenosis has been intensively studied. We aimed to investigate the power of serum IGF-I and TNF-alpha concentrations to predict restenosis in patients who had previously undergone PCI for STEMI. Thirty-seven patients were enrolled in the study. Twelve months prior to the study they underwent successful PCI with stent placement for STEMI. The patients were divided into two groups: group 1 - patients with in-stent restenosis in the infarct-related artery (N=9); group 2 - patients without in-stent restenosis in the infarct-related artery (N=28). Baseline profile was similar in both groups. The mean diameter and length of placed stents were similar in both groups. Smaller minimal lumen diameter (MLD) and greater lumen loss (LL) were observed in group 1. Median IGF-I concentrations were substantially higher in patients with ISR compared to those without ISR (170 ng/mL vs 115 ng/mL, p=0.004). Strikingly, median TNF-alpha levels were lower in group 1 (2.4 pg/mL vs 4.1 pg/mL, p=0.05). Correlation analysis showed that serum IGF-I levels were significantly associated with diameter stenosis (R=0.29 p=0.05), LL (R=0.37 p=0.02), MLD (R= -0.38 p=0.03), and stent length (R=0.30 p=0.05). The cut-off value to predict restenosis for IGF-I was less than 158 ng/mL (sensitivity 55 percent, specificity 93 percent, positive predictive value 71 percent, negative predictive value 87 percent). IGF-I detected twelve months after stent placement during the acute phase of AMI may be a late determinant of restenosis. High concentrations of IGF-I could play a permissive role in the progression of NIH and subsequently restenosis. It seems that as far as TNF-alpha is concerned, diagnostic value remains inconclusive.

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OBJECTIVES: The increasing incidence of overweight and obesity in modern societies, and the demonstration that adipose tissue produces numerous cytokines, increases interest of investigators in the associations between adipose tissue, adipokines, CRP and insulin resistance in rheumatoid arthritis (RA) and their possible role in the pathogenesis of this disease.The purpose of the study was to investigate serum levels of visfatin, resistin, hsCRP and insulin resistance in relation to abdominal obesity in patients with RA. METHODS: Serum levels of visfatin, resistin, hsCRP and glucose metabolism parameters were measured in 46 women with RA - 22 without abdominal obesity and 24 with abdominal obesity. RESULTS: Patients with RA and abdominal obesity showed significant lower visfatin levels (1.00+/-0.93 vs. 1.44+/-0.85 ng/ml; p<0.05) in comparison to those without abdominal obesity. We found significant correlations between levels of visfatin and resistin (r=0.41; p<0.01); and between resistin levels and hsCRP levels (r=0.41; p<0.01); resistin levels and leucocytes count (r=0.36; p<0.05); and resistin levels and ESR (r=0.30; p<0.05), in the whole investigated group. Visfatin as well as resistin did not correlate with anthropometric parameters or insulin resistance in whole patients with RA. CONCLUSIONS: In patients with RA and abdominal obesity, in comparison to patients without abdominal obesity, significantly lower visfatin levels have been demonstrated. Resistin was associated with laboratory markers of inflammation. Positive correlation between levels of visfatin and resistin may suggest that visfatin plays a role in inflammation in RA.

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Despite high efficacy of percutaneous coronary intervention (PCI), in-stent restenosis proves to be a significant problem of therapy. Restenosis concerns around 30 percent of patients. Studies have suggested that restenosis is initiated by cells which participate in intense inflammatory reaction caused by stent implantation. Atherosclerotic plaque rupture during stent implantation and PCI-associated injury of the vessel wall lead to hemorrhage and release of various cytokines. They are probably responsible for quick recurrence of vascular lumen stenosis (restenosis). Interleukin-6 (IL-6) is known as a main pro-inflammatory cytokine, whereas Transformig Growth Factor-beta1 (TGF-beta1) has anti-inflammatory properties. The study population comprised 36 patients with myocardial infarction treated with PCI with stent implantation. They underwent control coronary angiography after 12 months. At this time plasma concentration of IL-6 and TGF-beta was measured in peripheral blood. Serum IL-6 concentration in the analyzed population correlates with lumen loss (p<0.01) and the severity of stenosis (p<0.001). No such correlation was found between serum TGF-beta1 concentration and lumen loss (p=NS) or the severity of stenosis (p=NS). The IL-6 plasma concentration may be a marker of in-stent restenosis in patients after PTCA, while the concentration of TGF-beta1 is not associated with the occurrence of restenosis at one year of follow-up.

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Spectroscopic features of Eu3+, Nd3+ and Er3+ in nanocrystalline samples of gallium gadolinium garnet prepared by a modified sol-gel method were investigated in order to assess the structural compatibility of the material with a single crystal counterpart. Emission spectra and decay curves of luminescent admixtures were recorded and analysed. Observed distribution of spectral line intensities and single exponential time dependence of luminescence decay curves indicate strongly that the static disorder in the neighbourhood of luminescent ions is not significant, hence structural peculiarities of the garnet lattice encountered in bulk crystals are maintained. It has been concluded that the method of preparation applied is able to furnish good structural quality GGG nanocrystals.

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UNLABELLED: Statins, HMG-CoA reductase inhibitors are drugs with a potent lipid-lowering effect. They are also able to inhibit proliferation of smooth muscle cells, T-lymphocytes, to restore endothelial activity and to inhibit inflammatory responses. These effects have been called the pleiotropic effect of statins. Statins have demonstrated contrast to the inflammatory activity of macrophages. The aim of the study was to assess the influence of simvastatin on serum levels of proinflammatory cytokines such as IL-2 and TNFalpha in hypercholesterolemic patients. METHODS: In 58 non-smoking men with total cholesterol (TC) >7.8 mmol/L, LDL-cholesterol>5.5 mmol/L and fasting triglycerides<4.6 mmol/L serum IL-2 and TNFalpha were determined at the beginning of the study, after 3 months diet and after 3 months of simvastatin therapy (20 mg/day). The control group was composed of 10 healthy volunteers with correct lipid values: TC<5.2 mmol/L, LDL-cholesterol <2.3 mmol/L, HDL-cholesterol >1.5 mmol/L and triglycerides<2.3 mmol/L. RESULTS: There were significant reductions in IL-2 concentration after 3 months diet (p=0.0059) and significant (p=0.0003) decrease of IL-2 after 3 months of simvastatin therapy. Meanwhile we observed a significant decrease of TNFalpha concentration after 3 months diet (p=0.0001) and no significant decrease after 3 months of simvastatin therapy.

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UNLABELLED: TNF alpha receptors participate in programmed cell death. TNF R2 efficiently assists TNF R7 effects by ligand passing. Structure of TNF alpha receptors influences TNF activity in vivo and the structure of TNF R2 gene may suggest post-transcription modification based on alternative splicing. The aim of the study was to analyse the expression of gene coding TNF alpha receptors R2 and R7 by estimation of mRNA expression of differentiated thyroid carcinomas in comparison to surrounding tissue free from neoplastic infiltration and search for differently spliced TNF alpha R2/R7 isophorms. The study included seven patients with histopathologically confirmed follicular thyroid cancer. Tissue samples removed from tumor region were obtained from the follicular thyroid cancer patients undergoing surgical treatment. The samples were divided into two parts. The first one was routinely examined histopathologically, the second was used for RNA extraction and the number of TNF and its receptors mRNA copies were subsequently quantified. RESULTS: 1) The presence of TNF alpha expression was observed in all examined samples, in contrast to TNF R1 expression; 2) The high level of TNF alpha expression was noted both for typical and sought TNF R2/R7 isoforms and 3) A considerable number of samples displayed higher levels of TNF R2 isoforms than TNF R2/R7 mRNA expression. Genetic disregulation observed in neoplastic disease usually concerns dysfunction of cytokines receptor genes.

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The authors have described the connections between nervous and immune systems. Endogenous opioids are one of the factors linking both systems. Endogenous and exogenous opioids can modify the function of interferons, humoral factors, antibody production and lymphocytes' activation. Concurrently, some cytokines can modify the endogenous opioid system. The aim of this study was to asses whether the subcutaneous administration of IL-2 influences the Met-Enkephalins concentration in serum after IL-2 single administration due to renal cancer. The Met-Enk level was estimated with RIA method. The IL-2 single administration results in a significant decrease of Met-Enk in serum.

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At the Poznan Rheumatology Center in Srema synovectomy of the knee joint is one of the treatment methods applied in cases where "rheumatoid granules" occur in the knee, or in recurrent exudative infections. One of the essential elements of therapy is to begin post-operative rehabilitation with active exercises as soon as 48 hours after surgery. This method is used to eliminate adhesions in the operating field and achieve a full range of movement in the joint without the need to apply painful and injurious redressing of the joint. The procedure used with the patient after surgery and the choice of kinesitherapeutic methods is the result of many years of experience. Post-operative procedures are concluded within 2-3 weeks when the range of movement achieved in the joint is greater than or equal to pre-operative.

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The aim of our study was to assess Polish women's attitudes and possible acceptance of genetic tests for breast cancer susceptibility. The research was carried out in 1995-1996 and enrolled 200 women of different age, education and professional status who were asked to answer the questions included in a questionnaire. We estimate the percentage of women presenting different attitudes towards breast cancer genetic testing: 77% of women accepted genetic tests for breast cancer (BRCA) and 48% of women accepted informing their close relatives of the genetic tests results.

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Tumour Necrosis Factor alpha (TNF alpha) immunotherapy, in addition to that of Interleukin-2 immunotherapy, represents one of the most promising biotherapies for human neoplasms. In order to identify immunological parameters of prognostic value we studied changes in immune response during first cycle of treatment with hree TNF alpha. The study included 21 locally advanced or metastatic solid tumor patients (M/F:12/9 median age: 57 years, range 38-65) for whom no other standard therapy was available. TNF alpha was administered before midday by a 20-minute intravenous infusion at a dose of 75 microg/day for 5 consecutive days corresponding to one cycle. In the absence of progression two further cycles of TNF alpha were given at 14 day intervals during which the dose was increased by 50 microg/day i.e. 2nd cycle- 100 microg/day, 3rd cycle- 150 microg/day. Of 21 patients evaluated for both clinical and immunological responses, 4 had complete response and 4 patients had partial response. The present study suggests that TNF alpha biotherapy is not associated with an increase in the number of circulating lymphocytes. Regarding lymphocyte subtype, a slight increase has been observed as far as T lymphocyte subsets are concerned. The CD4/CD8 ratio in cancer patients treated with hree TNF alpha showed significantly lower values than before treatment. On the basis of in vitro experiments an increase in NK cell activation in tissue culture, in addition to an increase of LAK cells, was observed.

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Tumor Necrosis Factor alpha administered in the therapy of advanced cancer influences certain hormones and cytokines secretion. In turn, these also modulate the biological activity of Tumor Necrosis Factor alpha. It has been shown in several studies that the cytokine Interleukin -6 (IL)-6 is produced in response to various hormones and other cytokines eg. Tumor Necrosis Factor (TNF alpha). In our study we focused on the Interleukin-6 (IL-6) secretion in response to TNF alpha administration in 12 patients undergoing TNF alpha biotherapy due to advanced neoplastic disease. Plasma IL-6 was estimated prior and at various time points (2, 3, 5 a,d 12 hours) after TNF alpha intravenous infusion. IL-6 level was estimated with ELISA method. In conclusion, we suggest the stimulating influence of hrec TNF alpha administered as therapy for advanced cancer on IL-6 secretion.

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