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排序方式: 共有413条查询结果,搜索用时 125 毫秒
21.
Agata Buonacera Benedetta Stancanelli Michele Colaci Lorenzo Malatino 《International journal of molecular sciences》2022,23(7)
Over the last 10 years, the evaluation of the neutrophil-to-lymphocyte ratio (NLR) as an emerging marker of diseases has become a compelling field of bio-medical research. Although a precise and unique cut-off value has not been yet found, its role as a flag of immune system homeostasis is well established. NLR has a well-known prognostic value and independently correlates with mortality in the general population and in several specific subsets of disease (sepsis, pneumonia, COVID-19, cancer, etc.). Moreover, NLR was recently considered as part of the decision-making processes concerning the admission/recovery of patients with COVID-19 pneumonia. This review aims to provide an overview of the main use of this biomarker, focusing on the pathophysiology and the molecular basis underlying its central role as a reliable mirror of inflammatory status and adaptive immunity. 相似文献
22.
Kamil Komider Katarzyna Karska Agata Kozakiewicz Monika Lejman Joanna Zawitkowska 《International journal of molecular sciences》2022,23(7)
Acute lymphoblastic leukemia (ALL) is the most common malignancy among children. Despite the enormous progress in ALL therapy, resulting in achieving a 5-year survival rate of up to 90%, the ambitious goal of reaching a 100% survival rate is still being pursued. A typical ALL treatment includes three phases: remission induction and consolidation and maintenance, preceded by a prednisone prephase. Poor prednisone response (PPR) is defined as the presence of ≥1.0 × 109 blasts/L in the peripheral blood on day eight of therapy and results in significantly frequent relapses and worse outcomes. Hence, identifying risk factors of steroid resistance and finding methods of overcoming that resistance may significantly improve patients’ outcomes. A mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK-ERK) pathway seems to be a particularly attractive target, as its activation leads to steroid resistance via a phosphorylating Bcl-2-interacting mediator of cell death (BIM), which is crucial in the steroid-induced cell death. Several mutations causing activation of MAPK-ERK were discovered, notably the interleukin-7 receptor (IL-7R) pathway mutations in T-cell ALL and rat sarcoma virus (Ras) pathway mutations in precursor B-cell ALL. MAPK-ERK pathway inhibitors were demonstrated to enhance the results of dexamethasone therapy in preclinical ALL studies. This report summarizes steroids’ mechanism of action, resistance to treatment, and prospects of steroids therapy in pediatric ALL. 相似文献
23.
The objective of this study was to evaluate the potential of double wall material combinations, using legume protein (soy protein isolate and pea protein isolate) in combination with wheat dextrin soluble fiber or trehalose, as alternative materials for microencapsulation of flaxseed oil by spray drying. The obtained preparations, with oil content of 35%, were fine and difficult flowing powders, regardless of their composition. The 1% addition of silica to the powders significantly reduced their cohesiveness and improved their flowability. The efficiency of microencapsulation, calculated based on oil fat content, ranged from 62 to 98% and was higher in the powders with trehalose and in the powders containing soy protein. Effective protection against oxidation of microencapsulated oil was achieved in the protein-trehalose matrix, especially in the case of the vacuum-packed powders with pea protein during storage at refrigeration temperature. Replacing trehalose with soluble fiber enabled formation of powders less susceptible to caking under conditions of increased humidity, but it resulted in decreased microencapsulation efficiency. The combination of pea protein/carbohydrate resulted in the formation of microcapsules with porous structure, especially in the system with soluble fiber. With time, the structure of the primary emulsions and those reconstituted from powders containing pea protein changed from liquid to greasy and paste-like. 相似文献
24.
Janusz Blasiak Ewelina Synowiec Antero Salminen Kai Kaarniranta 《International journal of molecular sciences》2012,13(10):13378-13397
The pathogenesis of age-related macular degeneration (AMD) is complex and involves interactions between environmental and genetic factors, with oxidative stress playing an important role inducing damage in biomolecules, including DNA. Therefore, genetic variability in the components of DNA repair systems may influence the ability of the cell to cope with oxidative stress and in this way contribute to the pathogenesis of AMD. However, few reports have been published on this subject so far. We demonstrated that the c.977C>G polymorphism (rs1052133) in the hOGG1 gene and the c.972G>C polymorphism (rs3219489) in the MUTYH gene, the products of which play important roles in the repair of oxidatively damaged DNA, might be associated with the risk of AMD. Oxidative stress may promote misincorporation of uracil into DNA, where it is targeted by several DNA glycosylases. We observed that the g.4235T>C (rs2337395) and c.–32A>G (rs3087404) polymorphisms in two genes encoding such glycosylases, UNG and SMUG1, respectively, could be associated with the occurrence of AMD. Polymorphisms in some other DNA repair genes, including XPD (ERCC2), XRCC1 and ERCC6 (CSB) have also been reported to be associated with AMD. These data confirm the importance of the cellular reaction to DNA damage, and this may be influenced by variability in DNA repair genes, in AMD pathogenesis. 相似文献
25.
Marcin Janecki Micha Graczyk Agata Anna Lewandowska ukasz Pawlak 《International journal of molecular sciences》2022,23(8)
The COVID-19 pandemic caused by the SARS-CoV-2 virus made it necessary to search for new options for both causal treatment and mitigation of its symptoms. Scientists and researchers around the world are constantly looking for the best therapeutic options. These difficult circumstances have also spurred the re-examination of the potential of natural substances contained in Cannabis sativa L. Cannabinoids, apart from CB1 and CB2 receptors, may act multifacetedly through a number of other receptors, such as the GPR55, TRPV1, PPARs, 5-HT1A, adenosine and glycine receptors. The complex anti-inflammatory and antiviral effects of cannabinoids have been confirmed by interactions with various signaling pathways. Considering the fact that the SARS-CoV-2 virus causes excessive immune response and triggers an inflammatory cascade, and that cannabinoids have the ability to regulate these processes, it can be assumed that they have potential to be used in the treatment of COVID-19. During the pandemic, there were many publications on the subject of COVID-19, which indicate the potential impact of cannabinoids not only on the course of the disease, but also their role in prevention. It is worth noting that the anti-inflammatory and antiviral potential are shown not only by well-known cannabinoids, such as cannabidiol (CBD), but also secondary cannabinoids, such as cannabigerolic acid (CBGA) and terpenes, emphasizing the role of all of the plant’s compounds and the entourage effect. This article presents a narrative review of the current knowledge in this area available in the PubMed, Scopus and Web of Science medical databases. 相似文献
26.
Iwona Jóźwik Agata Strojny‐Nędza Marcin Chmielewski Katarzyna Pietrzak Łukasz Kurpaska Szymon Nosewicz 《Microscopy research and technique》2018,81(5):502-508
The performance of the present‐day scanning electron microscopy (SEM) extends far beyond delivering electronic images of the surface topography. Oxide dispersion strengthened (ODS) steel is on of the most promising materials for the future nuclear fusion reactor because of its good radiation resistance, and higher operation temperature up to 750°C. The microstructure of ODS should not exceed tens of nm, therefore there is a strong need in a fast and reliable technique for their characterization. In this work, the results of low‐kV SEM characterization of nanoprecipitates formed in the ODS matrix are presented. Application of highly sensitive photo‐diode BSE detector in SEM imaging allowed for the registration of single nm‐sized precipitates in the vicinity of the ODS alloys. The composition of the precipitates has been confirmed by TEM‐EDS. 相似文献
27.
Karolina Ossowska Agata Motyka-Pomagruk Natalia Kaczyska Agnieszka Kowalczyk Wojciech Sledz Ewa Lojkowska Zbigniew Kaczyski 《International journal of molecular sciences》2022,23(4)
Pectobacterium parmentieri is a pectinolytic plant pathogenic bacterium causing high economic losses of cultivated plants. The highly devastating potential of this phytopathogen results from the efficient production of plant cell wall-degrading enzymes, i.e., pectinases, cellulases and proteases, in addition to the impact of accessory virulence factors such as motility, siderophores, biofilm and lipopolysaccharide (LPS). LPS belongs to pathogen-associated molecular patterns (PAMPs) and plays an important role in plant colonization and interaction with the defense systems of the host. Therefore, we decided to investigate the heterogeneity of O-polysaccharides (OPS) of LPS of different strains of P. parmentieri, in search of an association between the selected genomic and phenotypic features of the strains that share an identical structure of the OPS molecule. In the current study, OPS were isolated from the LPS of two P. parmentieri strains obtained either in Finland in the 1980s (SCC3193) or in Poland in 2013 (IFB5432). The purified polysaccharides were analyzed by utilizing 1D and 2D NMR spectroscopy (1H, DQF-COSY, TOCSY, ROESY, HSQC, HSQC-TOCSY and HMBC) in addition to chemical methods. Sugar and methylation analyses of native polysaccharides, absolute configuration assignment of constituent monosaccharides and NMR spectroscopy data revealed that these two P. parmentieri strains isolated in different countries possess the same structure of OPS with a very rare residue of 5,7-diamino-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic acid (pseudaminic acid) substituted in the position C-8: →3)-β-d-Galf-(1→3)-α-d-Galp-(1→8)-β-Pse4Ac5Ac7Ac-(2→6)-α-d-Glcp-(1→6)-β-d-Glcp-(1→. The previous study indicated that three other P. parmentieri strains, namely IFB5427, IFB5408 and IFB5443, exhibit a different OPS molecule than SCC3193 and IFB5432. The conducted biodiversity-oriented assays revealed that the P. parmentieri IFB5427 and IFB5408 strains possessing the same OPS structure yielded the highest genome-wide similarity, according to average nucleotide identity analyses, in addition to the greatest ability to macerate chicory tissue among the studied P. parmentieri strains. The current research demonstrated a novel OPS structure, characteristic of at least two P. parmentieri strains (SCC3193 and IFB5432), and discussed the observed heterogenicity in the OPS of P. parmentieri in a broad genomic and phenotype-related context. 相似文献
28.
Dagmara Wojcik-Grzybek Magdalena Hubalewska-Mazgaj Marcin Surmiak Zbigniew Sliwowski Anna Dobrut Agata Mlodzinska Adrianna Wojcik Slawomir Kwiecien Marcin Magierowski Agnieszka Mazur-Bialy Jan Bilski Tomasz Brzozowski 《International journal of molecular sciences》2022,23(6)
Inflammatory bowel diseases (IBD) are commonly considered as Crohn’s disease and ulcerative colitis, but the possibility that the alterations in gut microbiota and oxidative stress may affect the course of experimental colitis in obese physically exercising mice treated with the intestinal alkaline phosphatase (IAP) has been little elucidated. Mice fed a high-fat-diet (HFD) or normal diet (ND) for 14 weeks were randomly assigned to exercise on spinning wheels (SW) for 7 weeks and treated with IAP followed by intrarectal administration of TNBS. The disease activity index (DAI), grip muscle strength test, oxidative stress biomarkers (MDA, SOD, GSH), DNA damage (8-OHdG), the plasma levels of cytokines IL-2, IL-6, IL-10, IL-12p70, IL-17a, TNF-α, MCP-1 and leptin were assessed, and the stool composition of the intestinal microbiota was determined by next generation sequencing (NGS). The TNBS-induced colitis was worsened in obese sedentary mice as manifested by severe colonic damage, an increase in DAI, oxidative stress biomarkers, DNA damage and decreased muscle strength. The longer running distance and weight loss was observed in mice given IAP or subjected to IAP + SW compared to sedentary ones. Less heterogeneous microbial composition was noticed in sedentary obese colitis mice and this effect disappeared in IAP + SW mice. Absence of Alistipes, lower proportion of Turicibacter, Proteobacteria and Faecalibacterium, an increase in Firmicutes and Clostridium, a decrease in oxidative stress biomarkers, 8-OHdG content and proinflammatory cytokines were observed in IAP + SW mice. IAP supplementation in combination with moderate physical activity attenuates the severity of murine colitis complicated by obesity through a mechanism involving the downregulation of the intestinal cytokine/chemokine network and oxidative stress, the modulation of the gut microbiota and an improvement of muscle strength. 相似文献
29.
Justyna Sienkiewicz-Gromiuk Liliana Mazur Agata Bartyzel Zofia Rz?czyńska 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(6):1325-1331
The reaction of sodium hydroxide with 2-aminoterephthalic acid leads to the formation of a complex of the general formula: [Na2(atpt)(H2O)5]·H2O, where atpt?=?[NH2C6H3(COO)2]2?. Sodium 2-aminoterephthalate was synthesized and characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, thermal analysis and coupled TG–FT-IR technique. Crystallographic study of the sodium complex reveals that the compound crystallizes in the triclinic system, the space group P-1 with a?=?7.983(3) ?, b?=?8.405(3) ?, c?=?11.311(5) ?, α?=?70.74(3)°, β?=?76.57(3)°, γ?=?83.12(3)° and V?=?696.1(5) ?3. On heating in air atmosphere the compound in question loses all water molecules in two steps in the temperature range 30–205?°C. The anhydrous form of the complex is stable up to 370?°C and then decomposes to sodium carbonate. 相似文献