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931.
Alzheimer's disease (AD) is the most frequent form of dementia among elderly. Despite the vast amount of literature on non-specific immune mechanisms in AD there is still little information about the potential antigen-specific immune response in this pathology. It is known that early stages of AD include β-amyloid (Aβ)- reactive antibodies production and inflammatory response. Despite some evidence gathered proving cellular immune response background in AD pathology, the specific reactions of CD4(+) and CD8(+) cells remain unknown as the previous investigations yielded conflicting results. Here we investigated the CD4(+)CD28(+) population of human peripheral blood T cells and showed that soluble β-amyloids alone were unable to stimulate these cells to proliferate significantly, resulting only in minor, probably antigen-specific, proliferative response. On the other hand, the exposure of in vitro pre-stimulated lymphocytes to soluble Aβ peptides significantly enhanced the proliferative response of these cells which had also lead to increased levels of TNF, IL-10 and IL-6. We also proved that Aβ peptide-enhanced proliferative response of CD4(+)CD28(+) cells is autonomous and independent from disease status while being associated with the initial, ex vivo activation status of the CD4(+) cells. In conclusion, we suggest that the effect of Aβ peptides on the immune system of AD patients does not depend on the specific reactivity to Aβ epitope(s), but is rather a consequence of an unspecific modulation of the cell cycle dynamics and cytokine production by T cells, occurring simultaneously in a huge proportion of Aβ peptide-exposed T lymphocytes and affecting the immune system performance. 相似文献
932.
Gaj P Maryan N Hennig EE Ledwon JK Paziewska A Majewska A Karczmarski J Nesteruk M Wolski J Antoniewicz AA Przytulski K Rutkowski A Teumer A Homuth G Starzyńska T Regula J Ostrowski J 《PloS one》2012,7(4):e35307
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933.
Andrzej Wuczyński Bartosz Smyk Paweł Kołodziejczyk Wiesław Lenkiewicz Grzegorz Orłowski Andrzej Pola 《Central European Journal of Biology》2012,7(3):495-506
South-western Poland belongs to the key staging areas for geese in Europe, supporting some 100000 birds in recent years. We
compared goose counts conducted in the 1970s, 1990s and during 2009–2011 in this region, and linked the findings to the recent
assessments of trends in the flyway-populations. Numbers increased several dozen times between the first two counts and have
stabilized to the present. More than 14% of the flyway Tundra Bean Goose (Anser fabalis rossicus) stopped over in SW Poland on passage. Smaller numbers of White-fronted Goose (A. albifrons), Greylag Goose (A. anser), and four other rarer species, have all increased since the 1970s. The likely factors responsible for these changes are
mild weather conditions, increased availability of large water bodies and shifts in winter ranges of particular species. Temporal
mismatch between SW Poland and the total flyways in Bean and White-fronted Geese was recorded when we compared the long-term
and the short-term population trends. Increasing reports of other species in SW Poland match the general tendencies in Europe.
These data document that regional trends are not a simple reflection of those in flyways as a whole. To understand changes
in goose populations a re-established international count network is desired. 相似文献
934.
Joanna Czarnecka Grzegorz Orłowski Jerzy Karg 《Central European Journal of Biology》2012,7(5):895-901
The role of frugivorous birds in dispersal of the seeds of fleshy-fruited plants is well understood, but other groups of birds
like granivores and omnivores can also act as vectors, especially in the process of non-standard dispersal. In this study
we examined the role of two widely distributed birds (the Eurasian Blackbird, Turdus merula, and the Black Redstart, Phoenicurus ochruros) in seed dispersal. We analyzed the content of 279 droppings of the Black Redstart collected between July and October and
85 droppings of the Eurasian Blackbird collected during January. In total we found 366 seeds, representing 11 plant taxa,
in the faecal samples; 93% of the seeds belonged to fleshy-fruited species. The most numerous were two native taxa, Sambucus racemosa/nigra, in summer and autumn, Crataegus monogyna in winter, and one alien species Morus alba, which is dispersed in summer. We also found seeds of four dry-fruited species; the most interesting of which was the presence
of anemochorous seeds of Solidago gigantea (a highly invasive alien species). The seeds were found only in droppings of the Eurasian Blackbird. Considering the obtained
results the need for further studies on bird-plant interactions should be a priority. 相似文献
935.
Malgorzata Szczepańska Przemyslaw Wirstlein Jana Skrzypczak Pawe? P Jagodziński 《Reproductive biology and endocrinology : RB&E》2012,10(1):1
Background
A decrease in HOXA11 expression in eutopic mid-secretory endometrium has been found in women with endometriosis-associated infertility. 相似文献936.
Witold Kycler Bronisława Szarzyńska Cezary Łoziński Konstanty Korski Katarzyna Lamperska 《Reports of Practical Oncology and Radiotherapy》2012,17(1):13-18
Background/aimThe aim of our study was to check how MGMT methylation status together with known factors influenced the risk of colon cancer development.Materials and methodsWe examined patients with colon polyps. Information concerning gender, age, lifestyle, diet, anthropometry and medical information, including cancer and family history of cancer, was analyzed. Polymorphism variety of MGMT gene was investigated in another study. Genetic analysis for MGMT methylation assessment was performed for polyp tissue samples from 143 patients.ResultsPositive methylation MGMT status was found in 55 patients. There was no correlation between gender and MGMT methylation status (p = 0.43). We did not find correlation between patients younger and older than 60 (p = 0.87). There was no correlation between smoking and MGMT methylation status (p = 0.36). We did not find correlation between BMI and MGMT methylation status (p = 0.86). We did not find correlation between MGMT methylation status and colon cancer in familial history (p = 0.45).ConclusionOur study showed no correlations between methylation status of MGMT polymorphisms and clinical features like age, gender, polyp localization, smoking status, or obesity. It has been shown previously that MGMT methylation status may show nonspecific methylation in colon polyps. Gene methylation status in adenoma tissues has also been associated by other authors with the adenoma's size, histology, and degree of atypia. In our study, we evaluated the gene methylation status in colon polyps and found no association with adenoma characteristics. The present study showed no correlation for MGMT methylation in polyps in different regions of colon. 相似文献
937.
Anna Mucha-Małecka Bogdan Gliński Marcin Hetnał Magdalena Jarosz Jacek Urbański Beata Frączek-Błachut Paweł Dymek Krzysztof Małecki Agnieszka Chrostowska 《Reports of Practical Oncology and Radiotherapy》2012,17(3):141-145
AimTo report the long-term follow-up of a cohort of adult patients with LGG post-operatively irradiated in one institution, and to identify prognostic factors for progression free survival.BackgroundThere is little consensus about the optimal treatment for low-grade glioma (LGG), and the clinical management of LGG is one of the most controversial areas in neurooncology. Radiation therapy is one option for treatment of patients with LGG, whereas other options include postoperative observation.Materials and methodsBetween 1975 and 2005, 180 patients with LGG (WHO II) received postoperative irradiation after non radical (subtotal or partial) excision. Patients had to be 18 years of age or older, and have histologic proof of supratentorial fibrillary (FA), protoplasmic (PA) or gemistocytic astrocytoma (GA). Radiotherapy was given within 3–10 weeks after surgery. Treatment fields were localized and included the preoperative tumor volume, with a 1–2 cm margin, treated to a total dose of 50–60 Gy in 25–30 fractions over 5–6 weeks.ResultsActuarial ten-year progression free survival (APFS) in the whole group was 19%. The worse prognosis was observed in patients with GA. Ten-year APFS rates for GA, PA and FA were 10%, 18% and 22%, respectively.ConclusionThe findings from our long-term cohort of 180 patients with LGG confirmed by uni- and multivariate analysis demonstrated that only astrocytoma histology significantly determined the prognosis. The best survival was observed in patients with the fibrillary variant, and the worst for the gemistocytic one. 相似文献
938.
Aleksandra Kładna Paweł Berczyński Irena Kruk Teresa Michalska Hassan Y. Aboul‐Enein 《Luminescence》2012,27(6):473-477
The direct effects of the four catecholamines (CATs), adrenaline (A), noradrenaline (NA), dopamine (D) and isoproterenol (I), on free radicals were investigated using the free radical 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH?) and hydroxyl radial (HO?). The CATs examined were found to inhibit the ESR signal intensity of DPPH? in a dose‐dependent manner over the range 0.1–2.5 mmol/L in the following order: NA > A > I > D, with IC50 = 0.30 ± 0.03 for noradrenaline and IC50 = 0.86 ± 0.02 for dopamine. Hydroxyl radicals were produced using a Fenton reaction in the presence of the spin trap 5,5‐dimethyl‐1‐pyrroline N‐oxide (DMPO), and ESR technique was applied to detect the CATs reactivity toward the radicals. The reaction rates constant (kr) of CATs with HO? were found to be in the order of 109 L/mol/s, and the kr value for noradrenaline was the highest (kr = 8.4 × 109 L/mol/s). The CATs examined exhibited also a strong decrease in the light emission (62–73% at 1 mmol/L concentration and 79–89% at 2 mmol/L concentration) from a Fenton‐like reaction. These reactions may be relevant to the biological action of these important polyphenolic compounds. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
939.
Vivian V. Costa Caio T. Fagundes Deborah F. Valad?o Daniel Cisalpino Ana Carolina F. Dias K��tia D. Silveira Lucas M. Kangussu Thiago V. ��vila Maria Rosa Q. Bonfim Daniela Bonaventura Tarc��lia A. Silva Lirlandia P. Sousa Milene A. Rachid Leda Q. Vieira Gustavo B. Menezes Ana Maria de Paula Alena Atrasheuskaya George Ignatyev Mauro M. Teixeira Danielle G. Souza 《PLoS neglected tropical diseases》2012,6(5)
940.