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961.
Mateusz?MolonEmail author Monika?Szajwaj Marek?Tchorzewski Andrzej?Skoczowski Ewa?Niewiadomska Renata?Zadrag-Tecza 《Age (Dordrecht, Netherlands)》2016,38(1):11
Despite many controversies, the yeast Saccharomyces cerevisiae continues to be used as a model organism for the study of aging. Numerous theories and hypotheses have been created for several decades, yet basic mechanisms of aging have remained unclear. Therefore, the principal aim of this work is to propose a possible mechanism leading to increased longevity in yeast. In this paper, we suggest for the first time that there is a link between decreased metabolic activity, fertility and longevity expressed as time of life in yeast. Determination of reproductive potential and total lifespan with the use of fob1Δ and sfp1Δ mutants allows us to compare the “longevity” presented as the number of produced daughters with the longevity expressed as the time of life. The results of analyses presented in this paper suggest the need for a change in the definition of longevity of yeast by taking into consideration the time parameter. The mutants that have been described as “long-lived” in the literature, such as the fob1Δ mutant, have an increased reproductive potential but live no longer than their standard counterparts. On the other hand, the sfp1Δ mutant and the wild-type strain produce a similar number of daughter cells, but the former lives much longer. Our results demonstrate a correlation between the decreased efficiency of the translational apparatus and the longevity of the sfp1Δ mutant. We suggest that a possible factor regulating the lifespan is the rate of cell metabolism. To measure the basic metabolism of the yeast cells, we used the isothermal microcalorimetry method. In the case of sfp1Δ, the flow of energy, ATP concentration, polysome profile and translational fitness are significantly lower in comparison with the wild-type strain and the fob1Δ mutant. 相似文献
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Thaer Khoury MD Carmelo Gaudioso MD PhD Yisheng V. Fang MD Souzan Sanati MD PhD Mateusz Opyrchal MD PhD Mohamed M. Desouki MD PhD Rouzan G. Karabakhtsian MD PhD Zaibo Li MD Dan Wang PhD Li Yan PhD Rebecca Jacobson MD 《The breast journal》2018,24(1):41-50
Breast carcinoma with skin ulceration (SU) is considered a locally advanced disease. The purpose of the study is to investigate if SU is an independent adverse factor. Breast carcinoma patients with SU (n=111) were included in the study. A subset (n=38, study cohort) was matched with cases that had no SU (n=38, matched cohort); the survival analyses were compared between these groups. Then, cases (n=80) were staged independent from SU into stage I, II or III. Disease free survival (DFS) and overall survival (OS) were analyzed. Patients with larger tumors tended to present with distant metastases more often than patients with smaller tumors (P=.004). In the matched cases, the 5‐year DFS probability was 53% for the study cohort and 58% for the matched cohort; and for OS 75% for the study cohort and 84% for the matched cohort with no statistical significant difference. However, there was a trend towards worse DFS for the patients whose tumors had SU. When the cases were staged based on tumor size and node status (I, II or III), the OS was statistically significant (P=.047) but not the DFS (P=.195). Relatively small tumors with SU had an extent of disease similar to that observed in patients with early stages disease. The survival analysis suggests that SU may not be an adverse factor. However, more cases are needed to further examine this finding. 相似文献
964.
Anna Kurek Mateusz Kucharczyk Jan Detka Joanna Ślusarczyk Ewa Trojan Katarzyna Głombik Bartosz Bojarski Agnieszka Ludwikowska Władysław Lasoń Bogusława Budziszewska 《Neurotoxicity research》2016,30(2):225-238
Elevated levels of glucocorticoids exert neurotoxic effects, and the hippocampus is particularly sensitive to the effects of glucocorticoids. Because some data have indicated that an increased action of glucocorticoids in the perinatal period enhances the susceptibility of brain tissue to adverse substances later in life, the main purpose of the present study was to compare necrotic/apoptotic corticosterone action in hippocampal organotypic cultures obtained from control animals with the effect of this steroid in tissue from prenatally stressed rats. Because the adverse effects of glucocorticoid action on nerve cell viability appear to result mainly from an increase in the intensity of the effects of glutamate and changes in growth factor and pro-inflammatory cytokine synthesis, the involvement of these factors in corticosterone action were also determined. In stress-like concentration (1 μM), corticosterone, when added to hippocampal cultures for 1 and 3 days, alone or jointly with glutamate, did not induce necrosis. In contrast, in 3-day cultures, corticosterone (1 μM) increased caspase-3 activity and the mRNA expression of the pro-apoptotic Bax. Moreover, corticosterone’s effect on caspase-3 activity was stronger in hippocampal cultures from prenatally stressed compared to control rats. Additionally, 24 h of exposure to corticosterone and glutamate, when applied separately and together, increased Bdnf, Ngf, and Tnf-α expression. In contrast, after 72 h, a strong decrease in the expression of both growth factors was observed, while the expression of TNF-α remained high. The present study showed that in stress-like concentrations, corticosterone exerted pro-apoptotic but not necrotic effects in hippocampal organotypic cultures. Prenatal stress increased the pro-apoptotic effects of corticosterone. Increased synthesis of the pro-inflammatory cytokine TNF-α may be connected with the adverse effects of corticosterone on brain cell viability. 相似文献
965.
An athlete’s performance depends not only on the shoes they wear but also on the surface used in sports facilities. In addition, it can significantly contribute to reducing injuries, which are easy to get during sports competitions. In the present study, we wanted to investigate whether recycled styrene butadiene rubber (SBR) and ethylene propylene diene monomer (EPDM) could be used in the production of sports surfaces. For this purpose, we designed three different sports surfaces: (1) SBR covered with a thin EPDM spray layer on the top, (2) clean EPDM, and (3) bottom SBR layer with the top layer of EPDM. The test program of these surfaces included in its scope: shock absorption, vertical deformation, tensile strength, abrasion resistance, and slip resistance tests. Our research also involved the influence of the substrate under surface, temperature, and surface conditions. Presented results show that both materials, in the right proportions, can be used in the production of sports surfaces. 相似文献
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Purpose of Review
Here we review potential therapeutic approaches for treating compulsive sexual behaviors (CSB; also known as hypersexual disorder). We present the therapeutic goals of several psychological and, pharmacological treatment approaches, and state of the research on their effectiveness.Recent Findings
To date, no systematic studies with control groups have been conducted in the field of CSB treatment; however, there are documented case studies and small-sample studies indicating potential effectiveness of pharmacological treatment with naltrexone and SSRIs as well as mindfulness, CBT, and 12-step-based treatment approaches.Summary
There is a whole field of CSB treatment waiting for systematic scientific investigation. Future research on CSB treatment should take in account a possibility of individual differences in psychological and neural mechanisms underlying CSB and help inform optimal selection of treatment modality for each patient.970.
Mateusz Siwak Marcin Maślankiewicz Wioletta Rozpędek Radosław Wojtczak Katarzyna Szymanek 《Ophthalmic genetics》2018,39(3):325-331
Background: Primary open-angle glaucoma (POAG) belongs to neurodegenerative diseases. Its etiology is not fully understood. However, a lot of reports have indicated that many biochemical molecules are involved in the retinal ganglion cell damage. Therefore, the purpose of this study was to evaluate a relationship between HDAC6, CXCR3, and SIRT1 genes expression levels with the occurrence risk of POAG and its progression.Materials and methods: The study included 34 glaucoma patients and 32 subjects without glaucoma symptoms. RNA was isolated from peripheral blood lymphocytes. Level of mRNA expression was determined by real-time PCR method.Results: Our results have shown significant association of the HDAC6 and SIRT1 expression levels with progression of POAG according to rim area (RA) value, p = 0.041; p = 0.012. Moreover, the analysis of the CXCR3 expression level showed a correlation with progression of POAG based on RA and cup disc ratio (c/d) value, p = 0.006 and p = 0.012, respectively.Conclusions: The expression level of HDAC6, CXCR3, and SIRT1 genes may be involved in the progression of POAG. 相似文献