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排序方式: 共有1097条查询结果,搜索用时 15 毫秒
61.
Barbora Peltanova Marketa Liskova Jaromir Gumulec Martina Raudenska Hana Holcova Polanska Tomas Vaculovic David Kalfert Marek Grega Jan Plzak Jan Betka Michal Masarik 《International journal of molecular sciences》2021,22(4)
Cancer-associated fibroblasts (CAFs) are one of the most abundant and critical components of the tumor stroma. CAFs can impact many important steps of cancerogenesis and may also influence treatment resistance. Some of these effects need the direct contact of CAFs and cancer cells, while some involve paracrine signals. In this study, we investigated the ability of head and neck squamous cell carcinomas (HNSCC) patient-derived CAFs to promote or inhibit the colony-forming ability of HNSCC cells. The effect of cisplatin on this promoting or inhibiting influence was also studied. The subsequent analysis focused on changes in the expression of genes associated with cancer progression. We found that cisplatin response in model HNSCC cancer cells was modified by coculture with CAFs, was CAF-specific, and different patient-derived CAFs had a different “sensitizing ratio”. Increased expression of VEGFA, PGE2S, COX2, EGFR, and NANOG in cancer cells was characteristic for the increase of resistance. On the other hand, CCL2 expression was associated with sensitizing effect. Significantly higher amounts of cisplatin were found in CAFs derived from patients who subsequently experienced a recurrence. In conclusion, our results showed that CAFs could promote and/or inhibit colony-forming capability and cisplatin resistance in HNSCC cells via paracrine effects and subsequent changes in gene expression of cancer-associated genes in cancer cells. 相似文献
62.
Sabina Kdzierska-Mieszkowska Michal Zolkiewski 《International journal of molecular sciences》2021,22(10)
This review focuses on the molecular chaperone ClpB that belongs to the Hsp100/Clp subfamily of the AAA+ ATPases and its biological function in selected bacterial pathogens, causing a variety of human infectious diseases, including zoonoses. It has been established that ClpB disaggregates and reactivates aggregated cellular proteins. It has been postulated that ClpB’s protein disaggregation activity supports the survival of pathogenic bacteria under host-induced stresses (e.g., high temperature and oxidative stress), which allows them to rapidly adapt to the human host and establish infection. Interestingly, ClpB may also perform other functions in pathogenic bacteria, which are required for their virulence. Since ClpB is not found in human cells, this chaperone emerges as an attractive target for novel antimicrobial therapies in combating bacterial infections. 相似文献
63.
Edyta Janik Marcin Niemcewicz Marcin Podogrocki Joanna Saluk-Bijak Michal Bijak 《International journal of molecular sciences》2021,22(11)
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
64.
Michal Kowara Sonia Borodzicz-Jazdzyk Karolina Rybak Maciej Kubik Agnieszka Cudnoch-Jedrzejewska 《International journal of molecular sciences》2021,22(11)
Myocardial infarction is one of the major causes of mortality worldwide and is a main cause of heart failure. This disease appears as a final point of atherosclerotic plaque progression, destabilization, and rupture. As a consequence of cardiomyocytes death during the infarction, the heart undergoes unfavorable cardiac remodeling, which results in its failure. Therefore, therapies aimed to limit the processes of atherosclerotic plaque progression, cardiac damage during the infarction, and subsequent remodeling are urgently warranted. A hopeful therapeutic option for the future medicine is targeting and regulating non-coding RNA (ncRNA), like microRNA, circular RNA (circRNA), or long non-coding RNA (lncRNA). In this review, the approaches targeted at ncRNAs participating in the aforementioned pathophysiological processes involved in myocardial infarction and their outcomes in preclinical studies have been concisely presented. 相似文献
65.
Janusz Blasiak Joanna Szczepanska Michal Fila Elzbieta Pawlowska Kai Kaarniranta 《International journal of molecular sciences》2021,22(13)
Age-related macular degeneration (AMD), the main cause of vision loss in the elderly, is associated with oxidation in the retina cells promoting telomere attrition. Activation of telomerase was reported to improve macular functions in AMD patients. The catalytic subunit of human telomerase (hTERT) may directly interact with proteins important for senescence, DNA damage response, and autophagy, which are impaired in AMD. hTERT interaction with mTORC1 (mTOR (mechanistic target of rapamycin) complex 1) and PINK1 (PTEN-induced kinase 1) activates macroautophagy and mitophagy, respectively, and removes cellular debris accumulated over AMD progression. Ectopic expression of telomerase in retinal pigment epithelium (RPE) cells lengthened telomeres, reduced senescence, and extended their lifespan. These effects provide evidence for the potential of telomerase in AMD therapy. Peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) may be involved in AMD pathogenesis through decreasing oxidative stress and senescence, regulation of vascular endothelial growth factor (VEGF), and improving autophagy. PGC-1α and TERT form an inhibitory positive feedback loop. In conclusion, telomerase activation and its ectopic expression in RPE cells, as well as controlled clinical trials on the effects of telomerase activation in AMD patients, are justified and should be assisted by PGC-1α modulators to increase the therapeutic potential of telomerase in AMD. 相似文献
66.
Michal Fila Jan Chojnacki Elzbieta Pawlowska Joanna Szczepanska Cezary Chojnacki Janusz Blasiak 《International journal of molecular sciences》2021,22(18)
Migraine, the leading cause of disability in the population aged below 50, is associated with functional gastrointestinal (GI) disorders (FGIDs) such as functional nausea, cyclic vomiting syndrome, and irritable bowel syndrome (IBS). Conversely, changes in intestinal GI transit may cause diarrhea or constipation and are a component of the autonomic symptoms associated with pre- and post-dorsal phases of migraine attack. These mutual relationships provoke a question on a common trigger in migraine and FGIDs. The kynurenine (l-kyn) pathway (KP) is the major route for l-tryptophan (l-Trp) metabolism and transforms l-Trp into several neuroactive compounds. Changes in KP were reported in both migraine and FGIDs. Migraine was largely untreatable, but several drugs approved lately by the FDA, including monoclonal antibodies for calcitonin gene-related peptide (CGRP) and its receptor, create a hope for a breakthrough in migraine treatment. Derivatives of l-kyn were efficient in pain relief with a mechanism including CGRP inhibition. KP products are important ligands to the aryl hydrocarbon receptor (AhR), whose activation is implicated in the pathogenesis of GI and migraine. Toll-like receptors (TLRs) may play a role in migraine and IBS pathogeneses, and KP metabolites detected downstream of TLR activation may be an IBS marker. The TLR4 signaling was observed in initiating and maintaining migraine-like behavior through myeloid differentiation primary response gene 88 (MyD88) in the mouse. The aim of this review is to justify the view that KP modulation may provide common triggers for migraine and FGIDs with the involvement of TLR, AhR, and MyD88 activation. 相似文献
67.
Jiří Čulík Marie Jurková Tomáš Horák Pavel Čejka Vladimír Kellner Josef Dvořák Pavel Karásek Michal Roth 《Journal of the Institute of Brewing》2009,115(3):220-225
The EBC method 7.7, currently used for determination of bitter acids in hop products, is a time‐consuming and laborious extraction technique. In this paper, our aim was to propose a new extraction method based on Pressurized Solvent Extraction (PSE) sometimes also called Pressurized Fluid Extraction (PFE) or Accelerated Solvent Extraction (ASE). Compared to conventional extractions, PSE offers a number of important benefits. PSE on OnePSE® automated extractor was used for extraction of α‐ and β‐acids from hops and hop products and the parameters influencing extraction efficiency and the influence of the sample preparation method were studied. The quantitative determination of α‐ and β‐acids in the extracts was accomplished by using an HPLC apparatus equipped with diode array detector. The experimental results were compared with those obtained by the standard EBC 7.7 method and the two methods were found to be fully compatible 相似文献
68.
Partition coefficients of phenol, salicylic acid, and several environmentally important chloro- and nitrophenols in a supercritical CO2-water system were measured using direct cocurrent extraction of aqueous solutions of the individual solutes with CO2. Partitioning data on the nitrophenols and salicylic acid were obtained for the first time. To bypass the troublesome and error-prone analysis of the CO2-rich phase, the present method employed only the solute concentrations in the aqueous phase before and after extraction to determine the partition coefficient. Unlike most previous engineering studies of phenol partitioning in a CO2-water system, the concentrations of phenolic solutes approached infinite dilution in both phases. This makes the results relevant to analytical-scale SFE of environmental water samples with CO2. Because of effective infinite dilution of the solutes, the partition coefficients provide a direct measure of relative CO2-philicity/hydrophilicity of the individual phenols. Compared to the octanol-water partition coefficients of substituted phenols, the CO2-water partition coefficients are more sensitive to substitution in the position neighboring the hydroxyl group. 相似文献
69.
Andrzej Buller Michal Joachimczak Juan Liu Katsunori Shimohara 《Artificial Life and Robotics》2005,9(4):197-201
This article presents the key assumptions and current status of the ATR Artificial Brain Project being undertaken to create
Volitron, a device equipped with circuitry that enables the emergence of thought. Such thought would be recognized from Volitron's
specific communication behaviors. The project consists of three complementary themes: psychodynamic architecture, brain-specific
evolvable hardware, and the management of brain-building. The psychodynamic architecture is designed to develop automatically,
driven by “pleasure” coming from discharges of tension gathered in special tension-accumulating devices. Tension-discharging
patterns come first of all from the robot's interactions with its care giver/provider. For the dedicated hardware, we developed
qcellular-automata (qCA), in which groups of uniform logic primitives (q-cells) serve as spike-train-processing units, as well as pulsed para-neural networks (PPNN) that can be evolved, using fuzzified
signals and a genetic algorithm combined with hill climbing, and converted into qCA. The psychodynamic ideas were tested using three robots: Neko, equipped with a pleasure-driven associator, Miao, equipped with MemeStorms (a special working memory in which conflicting ideas fight for access to the long-term memory and
actuators), and Miao+, whose brain is equipped with a growing neural network.
This work was presented in part at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30,
2004 相似文献
70.
The so-called permutation separability criteria are simple operational conditions that are necessary for separability of mixed
states of multipartite systems: (1) permute the indices of the density matrix and (2) check if the trace norm of at least
one of the resulting operators is greater than one. If it is greater than one then the state is necessarily entangled. A shortcoming
of the permutation separability criteria is that many permutations give rise to equivalent separability criteria. Therefore,
we introduce a necessary condition for two permutations to yield independent criteria called combinatorial independence. This
condition basically means that the map corresponding to one permutation cannot be obtained by concatenating the map corresponding
to the second permutation with a norm-preserving map. We characterize completely combina-torially independent criteria, and
determine simple permutations that represent all independent criteria. The representatives can be visualized by means of a
simple graphical notation. They are composed of three basic operations: partial transpose, and two types of so-called reshufflings.
In particular, for a four-partite system all criteria except one are composed of partial transpose and only one type of reshuffling;
the exceptional one requires the second type of reshuffling. Furthermore, we show how to obtain efficiently a simple representative
for every permutation. This method allows to check easily if two permutations are Combinatorially equivalent or not. 相似文献