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1.
Background: Ehlers-Danlos syndrome (EDS) is a common non-inflammatory, congenital connective tissue disorder. Classical type (cEDS) EDS is one of the more common forms, typically caused by mutations in the COL5A1 and COL5A2 genes, though causative mutations in the COL1A1 gene have also been described. Material and methods: The study group included 59 patients of Polish origin, diagnosed with cEDS. The analysis was performed on genomic DNA (gDNA) with NGS technology, using an Illumina sequencer. Thirty-five genes related to connective tissue were investigated. The pathogenicity of the detected variants was assessed by VarSome. Results: The NGS of 35 genes revealed variants within the COL5A1, COL5A2, COL1A1, and COL1A2 genes for 30 of the 59 patients investigated. Our panel detected no sequence variations for the remaining 29 patients. Discussion: Next-generation sequencing, with an appropriate multigene panel, showed great potential to assist in the diagnosis of EDS and other connective tissue disorders. Our data also show that not all causative genes giving rise to cEDS have been elucidated yet.  相似文献   
2.
Secondary amyloid A (AA) amyloidosis is an important complication of some chronic inflammatory diseases, primarily rheumatoid arthritis (RA). It is a serious, potentially life‐threatening disorder caused by the deposition of AA fibrils, which are derived from the circulatory, acute‐phase‐reactant, serum amyloid A protein (SAA). Recently, a specific interaction between SAA and the ubiquitous inhibitor of cysteine proteases—human cystatin C (hCC)—has been proved. Using a combination of selective proteolytic excision and high‐resolution mass spectrometry, the binding sites in the SAA and hCC sequences were assessed as SAA(86–104) and hCC(96–102), respectively. Here, we report further details concerning the hCC–SAA interaction. With the use of affinity tests and florescent ELISA‐like assays, the amino acid residues crucial for the protein interaction were determined. It was shown that all amino acid residues in the SAA sequence, essential for the formation of the protein complex, are basic ones, which suggests an electrostatic interaction character. The idea is corroborated by the fact that the most important residues in the hCC sequence are Ser‐98 and Tyr‐102; these residues are able to form hydrogen bonds via their hydroxyl groups. The molecular details of hCC–SAA complex formation might be helpful for the design of new compounds modulating the biological role of both proteins. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
3.
The photodynamic response of the anthraquinone anticancer drug aclarubicin (ACL) was investigated in vitro and compared with that of mitoxantrone (MTX). Cultured immortalized rodent B14 and NIH 3T3 cells were used in the experiments as a model for cells with neoplastic phenotype. Long-term cytotoxicity and inhibition of cell proliferation assayed by the clonal growth and MTT-tetrazolium methods were estimated to compare the efficacy of aclarubicin and mitoxantrone in photosensitizing cells and their death after non-thermal exposure to monochromatic laser light. Green He-Ne (543.5 nm) or red semiconductor (670 nm) low-power laser (LPL) irradiations were applied. Different dose-responses of both cell lines to aclarubicin and mitoxantrone were found so that the cytotoxicity of MTX was considerably greater than the cytotoxicity of ACL. Phototherapy response (P < 0.0001) was observed only for B14 cells after sensitisation with aclarubicin. Under the same conditions no significant effect of red light irradiation (semiconductor 670 nm laser) on survival of both cell lines treated with mitoxantrone was found.  相似文献   
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Background

Prostate cancer (PCa) and colorectal cancer (CRC) are the most commonly diagnosed cancers and cancer-related causes of death in Poland. To date, numerous single nucleotide polymorphisms (SNPs) associated with susceptibility to both cancer types have been identified, but their effect on disease risk may differ among populations.

Methods

To identify new SNPs associated with PCa and CRC in the Polish population, a genome-wide association study (GWAS) was performed using DNA sample pools on Affymetrix Genome-Wide Human SNP 6.0 arrays. A total of 135 PCa patients and 270 healthy men (PCa sub-study) and 525 patients with adenoma (AD), 630 patients with CRC and 690 controls (AD/CRC sub-study) were included in the analysis. Allele frequency distributions were compared with t-tests and χ2-tests. Only those significantly associated SNPs with a proxy SNP (p<0.001; distance of 100 kb; r2>0.7) were selected. GWAS marker selection was conducted using PLINK. The study was replicated using extended cohorts of patients and controls. The association with previously reported PCa and CRC susceptibility variants was also examined. Individual patients were genotyped using TaqMan SNP Genotyping Assays.

Results

The GWAS selected six and 24 new candidate SNPs associated with PCa and CRC susceptibility, respectively. In the replication study, 17 of these associations were confirmed as significant in additive model of inheritance. Seven of them remained significant after correction for multiple hypothesis testing. Additionally, 17 previously reported risk variants have been identified, five of which remained significant after correction.

Conclusion

Pooled-DNA GWAS enabled the identification of new susceptibility loci for CRC in the Polish population. Previously reported CRC and PCa predisposition variants were also identified, validating the global nature of their associations. Further independent replication studies are required to confirm significance of the newly uncovered candidate susceptibility loci.  相似文献   
7.
Airborne fungal spore concentrations in Szczecin, Poland, were studied between 2004 and 2006 with the objective of determining a seasonal variation in the concentrations of selected fungal spore types in relation to meteorological parameters. The presence of spores of five taxa, namely, Cladosporium, Ganoderma, Alternaria, Leptosphaeria and Didymella, was recorded using a volumetric method (Hirst type). Fungal spores were present in the air in large numbers during the summer, with the highest concentrations recorded mainly in June, July and August. The peak concentrations of two of the studied spore types, Ganoderma and Alternaria, occurred in August, while the concentrations of Cladosporium, Leptosphaeria and Didymella spores were the highest in July. Multiple regression analysis was performed for three fungal seasons—2004, 2005 and 2006. Spore concentration was found to be positively correlated with the minimum temperature. For some spore types, there was also a significant correlation between concentrations, relative humidity and rain.  相似文献   
8.
Recent human and animal studies have demonstrated that in severe end-stage heart failure (HF), the cardiac muscle switches to a more fetal metabolic phenotype, characterized by downregulation of free fatty acid (FFA) oxidation and an enhancement of glucose oxidation. The goal of this study was to examine myocardial substrate metabolism in a model of moderate coronary microembolization-induced HF. We hypothesized that during well-compensated HF, FFA oxidation would predominate as opposed to a more fetal metabolic phenotype of greater glucose oxidation. Cardiac substrate uptake and oxidation were measured in normal dogs (n = 8) and in dogs with microembolization-induced HF (n = 18, ejection fraction = 28%) by infusing three isotopic tracers ([9,10-(3)H]oleate, [U-(14)C]glucose, and [1-(13)C]lactate) in anesthetized open-chest animals. There were no differences in myocardial substrate metabolism between the two groups. The total activity of pyruvate dehydrogenase, the key enzyme regulating myocardial pyruvate oxidation (and hence glucose and lactate oxidation) was not affected by HF. We did not observe any difference in the activity of carnitine palmitoyl transferase I (CPT-I) and its sensitivity to inhibition by malonyl-CoA between groups; however, malonyl-CoA content was decreased by 22% with HF, suggesting less in vivo inhibition of CPT-I activity. The differences in malonyl-CoA content cannot be explained by changes in the Michaelis-Menten constant and maximal velocity for malonyl-CoA decarboxylase because neither were affected by HF. These results support the concept that there is no decrease in fatty acid oxidation during compensated HF and that the downregulation of fatty acid oxidation enzymes and the switch to carbohydrate oxidation observed in end-stage HF is only a late-stage phenomenon.  相似文献   
9.
Grass pea (Lathyrus sativus L.) is a legume crop known from its tolerance to various abiotic stresses, especially drought. In this study, we investigated: (1) the response of grass pea seedlings to osmotic stress generated in vitro by polyethylene glycol (PEG); (2) potential drought acclimatization mechanisms of two polish grass pea cultivars. Grass pea seeds of two cultivars were sown on media containing different PEG concentrations (0, 5.5, 11.0 mM) and cultivated for 14 days in controlled conditions. Plants’ dry matter increased under osmotic stress (regardless of PEG concentration). In turn, the highest dose of PEG caused a reduction in seedling growth in both cultivars. Furthermore, PEG caused the peroxidase activity increase in whole seedlings and catalase (CAT) activity in roots. However, differences between cultivars were noted in: CAT activity in shoots; while phenols and anthocyanin content as well as electrolyte leakage in shoots and roots. In turn, in both tested genotypes, accumulation of proline increased in shoots under osmotic stress. Obtained results indicate that the examined plants, although belonging to the same species, differ in acclimatization processes leading to elevated tolerance to osmotic stress.  相似文献   
10.
Seed size and shape, seed coat surface pattern, seed coat thickness, and endosperm structure were investigated in Androsace septentrionalis, Cortusa matthioli, Hottonia palustris, Primula elatior, Soldanella carpatica (Primulaceae), Anagallis arvensis, A. minima, Cyclamen purpurascens, Glaux maritima, Lysimachia nemorum, L. vulgaris, Trientalis europaea (Myrsinaceae), and Samolus valerandi (Theophrastaceae). Three seed size categories were distinguished on the basis of biometric measurements. Almost all seeds examined were found to be small with an angular shape classified as sectoroid or polyhedral. A new type of seed shape, suboval, was identified for H. palustris. Cyclamen purpurascens seeds differed from seeds of all other species examined because of their large size, subglobose shape, and concave hilar area. Despite the different shape types, the length/width ratio of the seeds examined was constant, while their hilum length/width ratio was a highly variable feature. Three types of seed surface patterns were observed: (1) reticulate, (2) tuberculate with secondary striations, and (3) poroid-alveolate with the presence of a spongy outer layer. For seeds of Anagallis arvensis, A. minima, Cortusa matthioli, Lysimachia nemorum, and Soldanella carpatica, secondary seed sculpture was described. The seed coats of all species examined were two-layered, and great differences in testa thickness were found (9.9?C128.6???m). In general, seeds of the Myrsinaceae species were more often characterized by thick testa. Different proportions in thickness of the inner and outer testa layers were observed. In seeds with reticulate seed patterns, the inner testa layer was twice to several times thicker than the outer layer, while the opposite proportions were observed in seeds with the tuberculate or poroid-alveolate seed sculpture pattern. In seeds of all species examined, oxalate crystals were present on the surface of the inner testa layer. Thus, the presence or absence of oxalate crystals in testa is not a feature distinguishing species with angular or subglobose seeds. Four types of endosperm structure were identified according to the thickness of the endosperm cell walls and the relief of their inner surface: (1) with evenly thickened and smooth cell walls, (2) with evenly thickened cell walls and circular or helical thickenings on their inside surfaces, (3) with very thick, but not evenly thickened cell walls with constrictions (??pitted??), and (4) with very thin papery and undulate cell walls. There is no rule concerning the seed shape, type of the seed sculpture, testa thickness, or endosperm structure that corresponds to the family affiliation of the species examined.  相似文献   
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