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The immunosenescence-related disproportion in T lymphocytes may have important consequences for endothelial dysfunction, which is a key event in vascular aging. The study was designed to assess the prognostic values of the inflammatory-immune profile to better predict and prevent vascular diseases associated with old age. Eighty individuals aged 70.9 ± 5.3 years were allocated to a low- (LGI) or high-grade inflammation (HGI) group based on CRP (<3 or ≥3 mg/L) as a conventional risk marker of cardiovascular diseases. Significant changes in inflammatory and endothelium-specific variables IL-1β, IL-6, TNFα, oxLDL, H2O2, NO, 3-nitrotyrosine, and endothelial progenitor cells (OR 7.61, 95% CI 2.56–29.05, p < 0.0001), confirmed their interplay in vascular inflammation. The flow-cytometry analysis demonstrated a high disproportion in T lymphocytes CD4+ and CD8+ between LGI and HGI groups. CRP was <3 mg/mL for the CD4/CD8 ratio within the reference values ≥ 1 or ≤2.5, unlike for the CD4/CD8 ratio < 1 and >2.5. The odds ratios for the distribution of CD4+ (OR 5.98, 95% CI 0.001–0.008, p < 0.001), CD8+ (OR 0.23, 95% CI 0.08–0.59, p < 0.01), and CD8CD45RO+ T naïve cells (OR 0.27, 95% CI 0.097–0.695, p < 0.01) and CD4/CD8 (OR 5.69, 95% CI 2.07–17.32, p < 0.001) indicated a potential diagnostic value of T lymphocytes for clinical prognosis in aging-related vascular dysfunction.  相似文献   
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Studies have shown differences in TAS2R38 receptor expression in patients with chronic rhinosinusitis (CRS) compared to healthy controls. Known agonists of TAS2R38 stimulate epithelial cells, leading to robust intracellular nitric oxide (NO) production, which damages bacterial membranes, enzymes, and DNA, but also increases ciliary beat frequency. In this study we examined, using qRT-PCR, the expression of TAS2R38 receptor in nasal polyps (NP) of patients with CRS (N = 107) and in inferior turbinate mucosa (ITM) of patients with CRS and controls (N = 39), and confronted it with clinical features and the severity of the disease. The expression was shown in 43 (50.00%) samples of ITM in the study group (N = 107), in 28 (71.79%) in the control group (N = 39) (p = 0.037), and in 43 (46.24%) of NP. There were no differences in levels of the expression in all analyzed tissues. Patients who rated their symptoms at 0–3 showed higher TAS2R38 expression in ITM in comparison to the patients with 8–10 points on the VAS scale (p = 0.020). A noticeable, however not significant, correlation between the TAS2R38 expression in ITM and the Lund–Mackay CT score was shown (p = 0.068; R = −0.28). Patients with coexisting asthma had significantly higher receptor expression in the NP (p = 0.012). Our study is the first to confirm the presence of the TAS2R38 receptor in NP. Expression of the TAS2R38 receptor is reduced in the sinonasal mucosa in patients with more advanced CRS with NP.  相似文献   
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The paper presents a solution of the inverse problem consisting in reconstruction of the heat flux and the distribution of temperature in the process of binary alloy solidification when the temperature measurements in the selected points of the alloy are known. The considered task is mathematically modelled by means of the heat conduction equation with the substitute thermal capacity and with the liquidus and solidus temperatures varying in dependence on the concentration of the alloy component, whereas for describing the concentration the lever arm model is applied. An important part of the procedure consists in minimization of some functional executed with the aid of ACO algorithm.  相似文献   
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The effect of thermal treatment over a wide range of temperature (130–280°C) on the crystallization behavior of nylon 6 was studied by using DSC, FTIR, and polarized light microscope equipped with a hot stage. The crystallization and the subsequent melting behavior of the nylon 6 samples treated at different temperatures (Ts) were classified into four types. When Ts was higher than 236°C or lower than 213°C, the crystallization behavior of nylon 6 was insensitive to the variation of Ts. When Ts was in the range of 213–235°C, the crystallization behavior was sensitive to the change of Ts. The polarized light microscopic experiments have demonstrated that a large amount of tiny ordered nylon 6 segments/cluster persisted when nylon 6 film are heated to 231°C. Consequently, the fastest crystallization speed was observed. As Ts was between 214 and 223°C, both the Tm and the ΔHm were higher than those of the nylon 6 samples treated at other temperature. The polarized light microscopic investigations have also demonstrated that molten nylon 6 crystallizes by using the un‐molten nylon 6 crystals as nucleation center at 220°C. Crystallization at higher temperature produces nylon 6 with thicker crystalline lamella. The above results are helpful for rational design of thermal treatment procedure to obtain nylon 6 with different crystalline features. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42413.  相似文献   
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Both obesity and esophageal adenocarcinoma (EAC) rates have increased sharply in the United States and Western Europe in recent years. EAC is a classic example of obesity-related cancer where the risk of EAC increases with increasing body mass index. Pathologically altered visceral fat in obesity appears to play a key role in this process. Visceral obesity may promote EAC by directly affecting gastroesophageal reflux disease and Barrett’s esophagus (BE), as well as a less reflux-dependent effect, including the release of pro-inflammatory adipokines and insulin resistance. Deregulation of adipokine production, such as the shift to an increased amount of leptin relative to “protective” adiponectin, has been implicated in the pathogenesis of BE and EAC. This review discusses not only the epidemiology and pathophysiology of obesity in BE and EAC, but also molecular alterations at the level of mRNA and proteins associated with these esophageal pathologies and the potential role of adipokines and myokines in these disorders. Particular attention is given to discussing the possible crosstalk of adipokines and myokines during exercise. It is concluded that lifestyle interventions to increase regular physical activity could be helpful as a promising strategy for preventing the development of BE and EAC.  相似文献   
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Chronic wound healing is currently a severe problem due to its incidence and associated complications. Intensive research is underway on substances that retain their biological activity in the wound microenvironment and stimulate the formation of new blood vessels critical for tissue regeneration. This group includes synthetic compounds with proangiogenic activity. Previously, we identified phosphorothioate analogs of nucleoside 5′-O-monophosphates as multifunctional ligands of P2Y6 and P2Y14 receptors. The effects of a series of unmodified and phosphorothioate nucleotide analogs on the secretion of VEGF from keratinocytes and fibroblasts, as well as their influence on the viability and proliferation of keratinocytes, fibroblasts, and endothelial cells were analyzed. In addition, the expression profiles of genes encoding nucleotide receptors in tested cell models were also investigated. In this study, we defined thymidine 5′-O-monophosphorothioate (TMPS) as a positive regulator of angiogenesis. Preliminary analyses confirmed the proangiogenic potency of TMPS in vivo.  相似文献   
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COVID-19 is a respiratory disease caused by newly discovered severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The disease at first was identified in the city of Wuhan, China in December 2019. Being a human infectious disease, it causes high fever, cough, breathing problems. In some cases it can be fatal, especially in people with comorbidities like heart or kidney problems and diabetes. The current COVID-19 treatment is based on symptomatic therapy, so finding an appropriate drug against COVID-19 remains an immediate and crucial target for the global scientific community. Two main processes are thought to be responsible for the COVID-19 pathogenesis. In the early stages of infection, disease is determined mainly by virus replication. In the later stages of infection, by an excessive immune/inflammatory response, leading to tissue damage. Therefore, the main treatment options are antiviral and immunomodulatory/anti-inflammatory agents. Many clinical trials have been conducted concerning the use of various drugs in COVID-19 therapy, and many are still ongoing. The majority of trials examine drug reposition (repurposing), which seems to be a good and effective option. Many drugs have been repurposed in COVID-19 therapy including remdesivir, favipiravir, tocilizumab and baricitinib. The aim of this review is to highlight (based on existing and accessible clinical evidence on ongoing trials) the current and available promising drugs for COVID-19 and outline their characteristics.  相似文献   
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Introduction and purpose of the study: SARS-CoV-2 virus does not only affect the respiratory system. It may cause damage to many organ systems with long-term effects. The latest scientific reports inform that this virus leaves a long-term trace in the nervous, circulatory, respiratory, urinary and reproductive systems. It manifests itself in disturbances in the functioning of the organs of these systems, causing serious health problems. The aim of the study was to review the latest research into the long-term effects of COVID-19 and determine how common these symptoms are and who is most at risk. Based on a literature review using the electronic scientific databases of PubMed and Web of Science on the long-term effects of SARS-CoV-2 infection, 88 studies were included in the analysis. The information contained in the analyzed literature shows that the SARS-CoV-2 virus can cause multi-organ damage, causing a number of long-term negative health complications. Conclusions: There is evidence that the virus can cause long-term complications lasting more than six months. They mainly concern disturbances in the functioning of the nervous, circulatory and respiratory systems. However, these studies are small or short-lasting, and many are speculative.  相似文献   
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