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31.
Dorota?S?owińska-KlenckaEmail author Martyna?Wojtaszek-Nowicka Stanis?aw?Sporny Ewa?Wo?niak-Ose?a Bo?ena?Popowicz Mariusz?Klencki 《BMC endocrine disorders》2016,16(1):69
Background
To determine the diagnostic efficacy of ultrasonographic malignancy risk features (UMRFs) in follicular lesions (FL) in a population with low risk of malignancy in FL and to compare it with a similar analysis in a group of patients with unequivocal cytology (UC): benign lesion (BL) or malignant neoplasm (MN).Methods
Presence of UMRFs (hypoechogenicity, solid echostructure, taller-than-wide shape, pathological vascularization, irregular margins, microcalcifications and macrocalcifications) and their sets were assessed in 322 FL: 202 follicular lesions of undetermined significance (FLUS) and 120 suspicious for follicular neoplasm (SFN) and 300 nodules with UC: 200 BL and 100 MN, subsequently evaluated histopathologically.Results
Cancers were confirmed in 100% nodules in MN group (89.0% of them were papillary carcinomas - PTC), in 6.4% FLUS nodules (69.2% PTC), and in 10.8% SFN nodules (30.8% PTC). In the UC group all UMRFs occurred more frequently in cancers than in benign lesions. In the FL group only calcifications were found in cancers more frequently – macro and microcalcifications together: 34.6 vs. 11.5% (p?=?0.001) and isolated macrocalcifications: 26.0 vs. 6.8% (p?=?0.001); the presence of those features increased the basic risk of malignancy in FL more than 2 times. The presence of at least 2 of the following URMFs: hypoechogenicity, solid echostructure, any type of calcifications and suspected shape, additionally improved sensitivity.Conclusions
Evaluation of UMRFs in FLs is less effective than in nodules with UC, and its effectiveness decreases parallel to the decrease in percentage of PTCs among malignant neoplasms and to the increase of the percentage of adenomas among benign nodules. The presence of macrocalcifications in such FLs significantly increases the basic risk of malignancy in these nodules.32.
33.
Łukasz Mokros Michał Seweryn Karbownik Katarzyna Nowakowska-Domagała Janusz Szemraj Łukasz Wieteska Karol Woźniak 《Biological Rhythm Research》2016,47(6):865-871
Background: There is barely any evidence of antipsychotic drugs affecting the molecular clockwork in human, yet it is suggested that clock genes are associated with dopaminergic transmission, i.e. the main target of this therapeutics. We decided to verify if haloperidol and olanzapine affect expression of CLOCK, BMAL1, PER1 and CRY1 in a human central nervous system cell line model. Methods: U-87MG human glioblastoma cell line was used as an experimental model. The cells were incubated with or without haloperidol and olanzapine in the concentration of 5 and 20 μM for 24 h. Real-time quantitative polymerase chain reaction with the ΔCT analysis was used to examine the effect of haloperidol and olanzapine on the mRNA expression of the genes. Results: At 5 μM, haloperidol decreased expression of CRY1 almost 20-fold. There was nearly a 1.5-fold increase in expression of PER1. Considering the 20 μM haloperidol concentration and both olanzapine concentrations, no other statistically significant effect was observed. Conclusions: At certain concentration, haloperidol seems to affect expression of particular clock genes in a human central nervous system cell line model, yet mechanism underlying this phenomenon remains elusive. 相似文献
34.
Marzec-Wróblewska Urszula Kamiński Piotr Łakota Paweł Szymański Marek Wasilow Karolina Ludwikowski Grzegorz Jerzak Leszek Stuczyński Tomasz Woźniak Alina Buciński Adam 《Biological trace element research》2019,188(2):251-260
Biological Trace Element Research - We analyzed cobalt (Co), chromium (Cr), and lead (Pb) concentrations in human semen and catalase CAT activity in seminal plasma and the effects of their... 相似文献
35.
Re-aeration-induced oxidative stress and antioxidative defenses in hypoxically pretreated lupine roots 总被引:1,自引:0,他引:1
The level of free radicals and activities of antioxidative enzymes were examined in roots of lupine seedlings (Lupinus luteus L.) that were deprived of oxygen by subjecting them to root hypoxia for 48 and 72 h and then re-aerated for up to 24 h. Using electron paramagnetic resonance (EPR), we found that the exposure of previously hypoxically grown roots to air caused the increase in free radicals level, irrespective of duration of hypoxic pretreatment. Immediately after re-aeration the level of free radicals was two times higher than in aerated control. The EPR signal with the g-values at the maximum absorption of 2.0057 and 2.0040 implied that the paramagnetic radicals are derived from a quinone. Directly after re-aeration of hypoxically pretreated roots, the activity of superoxide dismutase (SOD, EC 1.15.1.1) increased to its highest value, followed by a decline below the initial level, whereas activities of catalase (CAT, EC 1.11.1.6) and peroxidase (POX, EC 1.11.1.7) were diminished or only slightly influenced during re-aeration. The electrophoretic patterns of the soluble extracts show 4 isozymes of SOD, 4 isozymes of POX and 1 isozyme of CAT. The level of H2O2 was enhanced or lowered by re-aeration, depending on the previous duration of hypoxia. At the onset of re-aeration products of lipid peroxidation were present at a three-fourth of the levels found in aerobic control. Their levels increased after prolonged exposure to air but remained lower than those in aerobic control even after 24 h of re-aeration. Re-admission of oxygen resulted in about 20% rise in oxygen uptake by root axes segments immediately after transfer of roots from hypoxia and the high uptake rates were observed over whole re-aeration period. Oxygen consumption by root tips was significantly reduced just after transfer from hypoxic conditions as compared to aerated control but after 24 h of re-aeration even approached the control level. The results are discussed in relation to the ability of lupine roots to cope with oxidative stress caused by re-aeration following hypoxic pretreatment. 相似文献
36.
In previous clinical studies, dilation of afferent lymphatics and enlargement of inguinal lymph nodes (LN) were observed in lymphoscintigrams from patients with persistent posttraumatic edema of lower extremities after fractures and trauma of soft tissues. In this study, changes in rat popliteal and iliac lymph nodes draining lymph from the site of tibial fracture and adjacent soft tissue injury were investigated. The observed parameters were lymph node weight, cell number, phenotype frequency, cell cytokine expression, and reactivity to mitogens. The key observations included: a) increase in the weight and total cell number of the lymph nodes; b) increased autotransformation rate and responsiveness of lymph node cells to mitogen; c) decreased frequency of ED1 macrophages and activated OX8 cytotoxic cells in flow cytometry analysis; d) high expression of OX6 class II-positive, OX7 (stem cells), OX62 (migrating dendritic cells), ED1 (macrophages), and OX12 (B cells) on immunohistochemical sections of LNs with some few HIS48 (granulocytes); e) high expression of NOS3 and TGF beta by lymph node lymphocytes and endothelial cells. In summary, local lymph nodes reacted to internal wounds, such as bone fracture and injury to adjacent tissues, through mobilization of cells from the blood circulation, along with activation of cellular subsets. The molecular mechanism that provides the signal for this reaction remains unknown. The absence of major changes in the frequency of lymph node cell subpopulations indicates that lymph nodes are constitutively prepared for influx of antigens from damaged tissues and react only with increase in cell number and cell activation. The nature of the reaction, including lack of immunization against autoantigens, remains unclear. Further elucidation will require studies on the mechanism of cross-tolerance to self-antigens during wound healing. 相似文献
37.
38.
De novo methylation of MMLV provirus in embryonic stem cells: CpG versus non-CpG methylation 总被引:7,自引:0,他引:7
Nuclear factor Y (NF-Y) is a highly conserved trimeric activator that recognizes with high specificity and affinity the widespread CCAAT box promoter element. We previously cloned the genes of 23 NF-Y genes of Arabidopsis thaliana (Gene 264 (2001) 173). Now that the Arabidopsis genome sequencing project is complete, we present the cloning, alignments and expression profiles of the remaining six genes coding for the three NF-Y subunits. Consistent with our previous reports, most of the new members of the three subunits show a unique tissue-specific pattern, while another AtNF-YC9 is rather ubiquitous. 相似文献
39.
Rottbauer W Saurin AJ Lickert H Shen X Burns CG Wo ZG Kemler R Kingston R Wu C Fishman M 《Cell》2002,111(5):661-672
Organ size is precisely regulated during development, but the control mechanisms remain obscure. We have isolated a mutation in zebrafish, liebeskummer (lik), which causes development of hyperplastic embryonic hearts. lik encodes Reptin, a component of a DNA-stimulated ATPase complex. The mutation activates ATPase activity of Reptin complexes and causes a cell-autonomous proliferation of cardiomyocytes to begin well after progenitors have fashioned the primitive heart tube. With regard to heart growth, beta-catenin and Pontin, a DNA-stimulated ATPase that is often part of complexes with Reptin, are in the same genetic pathways. Pontin reduction phenocopies the cardiac hyperplasia of the lik mutation. Thus, the Reptin/Pontin ratio serves to regulate heart growth during development, at least in part via the beta-catenin pathway. 相似文献
40.
Jarzabek K Laudański P Dziecioł J Dabrowska M Wołczyński S 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2002,40(2):193-194
Members of protein kinase C (PKC) family have been widely implicated in the regulation of cell proliferation, differentiation and survival. Increased protein C activity in malignant breast tissue and in most aggressive breast cancer cell lines suggests possible role of PKC in the development and progression of breast cancer. PKC may be therefore a target for breast cancer treatment. In our study we attempted to investigate the effect of: phorbol ester (PMA)-PKC activator, and bisindolylmaleimide II (GF II), a highly selective PKC inhibitor, on the proliferation as well as induction of apoptosis and necrosis in breast cancer cell line MDA-MB-231. Our results provide evidence for multidirectional effects of PKC on the proliferation of this type of breast cancer cells. The effects of both compounds were different after short time of exposition (1-3 h). PMA induced proliferation, while GF II showed an opposite effect. After 24 h, however, both compounds exhibited relatively high inhibitory effect on the proliferation and proved to be effective in induction of necrosis and apoptosis. 相似文献