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541.
The aim of our study was to estimate the cholesterol concentrations in high density lipoprotein subfractions (HDL2 i HDL3) in plasma of patients with normocholesterolemia and atherosclerosis of coronary arteries and in patients with myeloproliferative diseases. Blood samples from patients with normal plasma cholesterol levels were analyzed in spite of the fact that atherosclerosis of coronary arteries usually exist with hypercholesterolemia and myeloproliferative diseases usually coexist with hypocholesterolemia. In this way we wanted to determine changes in HDL2 i HDL3 metabolism which occur independently from changes of cholesterol levels in other lipoproteins. Our results showed that in patients suffering from atherosclerosis of coronary arteries with normolipemia the lowering of plasma cholesterol level in subfractions HDL2 and HDL3 was observed. In patients with myeloproliferative disease with normocholesterolemia the slight lowering of cholesterol level in subfraction HDL3 may be connected with moderate hypertriglyceridemia. In both groups of patients the lowering of HDL cholesterol in plasma was accompanied with the increased lipid peroxidation.  相似文献   
542.

Objectives

Current studies concentrate on the cytokine network and its role in the pathogenesis of spondyloarthritis (SpA). In this study, we analyzed whether the serum cytokine profile (interleukins: IL-10, IL-11, IL-12, IL-15, IL-17, IL-23 and IL-33) correlates with demographic data, clinical manifestations, disease activity and treatment outcome in a group of patients with axial spondyloarthritis.

Material and methods

Forty-nine patients with an established diagnosis of axial spondyloarthritis (aSpA) and 19 healthy volunteers as controls were enrolled in the study. Clinical evaluation included patient''s medical history, 44 joint count, back pain intensity and global disease activity in the preceding week (VAS), the duration of morning stiffness and blood tests. Disease activity was assessed using BASDAI and ASDAS-CRP. Serum concentration of IL-10, IL-11, IL-12, IL-15, IL-17, IL-23 and IL-33 was determined.

Results

In patients with aSpA, elevated serum concentration of IL-10, IL-15, IL-17 and IL-23 was detected. In the aSpA group we detected higher values of serum concentration of IL-23 and IL-33 in the subgroup with anterior uveitis (83.1 ±184.0 pg/ml vs. 14.0 ±17.1 pg/ml, p < 0.0001 and 45.5 ±71.9 pg/ml vs. 18.4 ±14.3 pg/ml, p < 0.0001, respectively). Additionally, in the subgroup with peripheral arthritis, elevation of serum concentration of IL-12 (249.3 ±246.9 pg/ml vs. 99.9 ±105.9 pg/ml, p = 0.0001) was detected. Patients with preradiological SpA had higher serum concentration of IL-17 than patients with established diagnosis of AS (6.37 ±8.50 pg/ml vs. 2.04 ±2.98 pg/ml, p = 0.0295). No differences in serum concentration of analyzed cytokines were found between the subgroup with low to moderate disease activity and the subgroup with high to very high disease activity.

Conclusions

We report that in aSpA patients, compared to controls, elevated serum concentrations of IL-10, IL-15, IL-17 and IL-23 were observed. Some cytokines may predispose to a more severe course of aSpA.  相似文献   
543.
Endocannabinoids contract, relax or do not affect vessels with different calibre and tone in the pulmonary circulation in four species. The aim of the present study was to determine the mechanisms involved in the anandamide-induced relaxation of human pulmonary arteries (hPAs). Studies were performed in the isolated hPAs pre-constricted with the prostanoid TP receptor agonist, U-46619. To detect fatty acid amide hydrolase (FAAH) expression, Western blots were used. Anandamide concentration dependently relaxed the endothelium-intact hPAs pre-constricted with U-46619. The anandamide-induced relaxation was virtually abolished by removal of the endothelium and strongly attenuated by inhibitors of cyclooxygenases (indomethacin, COX-1/COX-2, and nimesulide, COX-2), nitric oxide synthase (N G -nitro-l-arginine methyl ester) given separately or in combination, FAAH (URB597), and the prostanoid IP receptor antagonist, RO1138452. The anandamide-evoked relaxation in the endothelium-intact vessels was attenuated in KCl pre-constricted preparations or by the inhibitor of large-conductance Ca2+-activated K+ channels, iberiotoxin. In experiments performed in the presence of URB597 to exclude effects of anandamide metabolites, the antagonist of the endothelial cannabinoid receptor, O-1918, diminished the anandamide-evoked relaxation whereas the antagonists of cannabinoid CB1, CB2 and vanilloid TRPV1 receptors, AM251, SR144528 and capsazepine, respectively, had no effect. Western blot studies revealed the occurrence of FAAH protein in the hPAs. The present study shows that anandamide breakdown products, cyclooxygenase pathways, nitric oxide, potassium channels and the O-1918-sensitive cannabinoid receptor play a role in the anandamide-induced relaxation of the hPAs with intact endothelium.  相似文献   
544.
Superabsorbent polymers (SAPs) are used in agriculture and environmental engineering to increase soil water retention. Under such conditions, the swelling pressure of the SAP in soil affects water absorption by SAP, and soil structure. The paper presents the results of swelling pressure of three cross-linked copolymers of acrylamide and potassium acrylate mixed at the ratios of 0.3%, 0.5% and 1.0% with coarse sand and loamy sand. The highest values of swelling pressure were obtained for the 1% proportion, for coarse sand (79.53 kPa) and loamy sand (78.23 kPa). The time required to reach 90% of swelling pressure for each type of SAP differs. Samples of coarse sand mixed with SAP K2 in all concentrations reached 90% of total swelling pressure in 100 min, while the loamy sand mixtures needed only about 60 min. The results were the basis for developing a model for swelling pressure of the superabsorbent and soil mixtures, which is a fully stochastic model. The conducted research demonstrated that the course of pressure increase depends on the available pore capacity and the grain size distribution of SAPs. The obtained results and the proposed model may be applied everywhere where mixtures of SAPs and soils are used to improve plant vegetation conditions.  相似文献   
545.
Polylactide-based composites filled with waste fillers due to their sustainability are a subject of many current papers, in which their structural, mechanical, and thermal properties are evaluated. However, few studies focus on their behavior in low temperatures. In this paper, dynamic and quasi-static mechanical properties of polylactide-based composites filled with 10 wt% of linseed cake (a by-product of mechanical oil extraction from linseed) were evaluated at room temperature and at −40 °C by means of dynamic mechanical analysis (DMA), Charpy’s impact strength test and uniaxial tensile test. It was found that the effect of plasticization provided by the oil contained in the filler at room temperature is significantly reduced in sub-zero conditions due to solidification of the oil around −18 °C, as it was shown by differential scanning calorimetry (DSC) and DMA, but the overall mechanical performance of the polylactide-based composites was sufficient to enable their use in low-temperature applications.  相似文献   
546.
The article presents changeability of renal resistive index (RRI) in various cardiovascular diseases and considers the usefulness of the marker and interpretational difficulties of the index. The values of RRI are not specific to an individual disease, but in a selected group of patients, it seems to be a perfect marker of cardiovasculorenal changes and a predictor of rapid loss of a renal function. The RRI usually does not reflect the vascular resistance, but is dependent on total and local vascular bed compliance changing with age, in the course of consecutive diseases and the influence of drugs. Under specific conditions, RRI appears to be a good marker of vascular damage. This review summarizes current concepts in RRI interpretation against the cardiovascular pathologies, focusing on the vascular damage association with regard to the complex nature of RRI value variability.  相似文献   
547.

Background

Melanoma of unknown primary site (MUP) is not a completely understood entity with nodal metastases as the most common first clinical manifestation. The aim of this multicentric study was to assess frequency and type of oncogenic BRAF/NRAS/KIT mutations in MUP with clinically detected nodal metastases in relation to clinicopathologic features and outcome.

Materials and Methods

We analyzed series of 103 MUP patients (period: 1992–2010) after therapeutic lymphadenectomy (LND): 40 axillary, 47 groin, 16 cervical, none treated with BRAF inhibitors. We performed molecular characterization of BRAF/NRAS/KIT mutational status in nodal metastases using direct sequencing of respective coding sequences. Median follow-up time was 53 months.

Results

BRAF mutations were detected in 55 cases (53 %) (51 V600E, 93 %; 4 others, 7 %), and mutually exclusive NRAS mutations were found in 14 cases (14 %) (7 p.Q61R, 4 p.Q61K, 2 p.Q61H, 1 p.Q13R). We have not detected any mutations in KIT. The 5-year overall survival (OS) was 34 %; median was 24 months. We have not found significant correlation between mutational status (BRAF/NRAS) and OS; however, for BRAF or NRAS mutated melanomas we observed significantly shorter disease-free survival (DFS) when compared with wild-type melanoma patients (p = .04; 5-year DFS, 18 vs 19 vs 31 %, respectively). The most important factor influencing OS was number of metastatic lymph nodes >1 (p = .03).

Conclusions

Our large study on molecular characterization of MUP with nodal metastases showed that MUPs had molecular features similar to sporadic non-chronic-sun-damaged melanomas. BRAF/NRAS mutational status had negative impact on DFS in this group of patients. These observations might have potential implication for molecular-targeted therapy in MUPs.  相似文献   
548.
The cytotoxic and antitumor activity of DIMIQ (5,11-dimethyl-5H-indolo[2,3-b]quinoline), synthetic analog of neocryptolepine, makes this compound a potential antitumor agent. An attempt to obtain liposomal form of DIMIQ·HCl was undertaken in the present study. Standard experimental conditions were chosen and information on the physicochemical parameters of the liposome dispersion containing studied indoloquinoline agent was collected. The effective and efficient encapsulation of DIMIQ·HCl (66.6%) in conventional liposomes (FAT-MLV, DMPC:DMPG 7:3 w/w at pH 7.0), uniformity of the size of liposomal vesicles, and high stability at pH 6.5 were demonstrated. Hemolysis of sheep erythrocytes induced by free form of DIMIQ·HCl was dramatically decreased after addition of liposome-entrapped DIMIQ·HCl. Treatment of hepatoma Morris 5123 cells for 24 hr with different concentrations of both free and its liposomal formulation of DIMIQ·HCl resulted in significant changes in cell morphology accompanied by reduction of cell viability.  相似文献   
549.
550.
A case of a 75-year-old female with a giant left atrial myxoma (54 x 42 mm in transthoracic echocardiography) is presented. She remained in a stable condition, however, developed a low cardiac output syndrome shortly after echocardiographic examination. This was caused by tumour displacement from the atrial wall into the left ventricle. The patient underwent urgent surgery during which the tumour was successfully removed. Histopathological examination confirmed the diagnosis of myxoma. Six months after surgery the patient is doing well.  相似文献   
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