Publications by authors named "Jirousek M"

Composting facilities are habitats where biological materials are bio-oxidized. Biological waste represents a source of plant species diaspores and may promote changes in the species composition of the surrounding. The studied composting facility is situated in the Bohemian-Moravian Highlands, Czech Republic.

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An undesired succession of rich fens leads to the formation of dense Sphagnum carpets that outcompete brown mosses and some vascular plants, resulting in biodiversity loss in fen habitats of high conservation importance. Small-scale Sphagnum removal is a rarely implemented conservational measure, whose success may depend on soil alkalinity and fertility (i.e.

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Background/aim: This study aimed at contributing to a better diagnosis of lung cancer by analyzing the patient's symptoms and their linkage to other characteristics.

Patients And Methods: We analyzed the data of 3,322 patients from LUCAS (LUngCAncerfocuS) National Registry of the Czech Republic. Overall survival was assessed using the Kaplan-Meier method.

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Background/aim: LUCAS is a clinical lung cancer registry (ClinicalTrials.gov identifier is NCT04228237), prospectively collecting data from newly diagnosed lung cancer patients in seven pneumooncology centers in the Czech Republic, since June 1, 2018. The aim of the study was to assess the stage of the disease at the time of diagnosis, percentage of morphological types, survival, percentage of driving mutations, eligibility for radical surgery, and percentage of patients who undergo radical surgery, in the non-smoking population in comparison with smokers and former smokers.

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Aim: To investigate potential association between administration of corticosteroids, antibiotics, probiotics, proton pump inhibitors, non-steroidal anti-inflammatory drugs (NSAID), statins and metformin and outcome in patients with non-small cell lung cancer (NSCLC) treated with nivolumab.

Patients And Methods: A total of 224 patients with advanced NSCLC treated at nine comprehensive cancer centers were analyzed in this national retrospective study. Survival statistics were evaluated using Kaplan-Meier method and Cox analysis.

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CAT-2003 is a novel conjugate of eicosapentaenoic acid (EPA) and niacin designed to be hydrolyzed by fatty acid amide hydrolase to release EPA inside cells at the endoplasmic reticulum. In cultured liver cells, CAT-2003 blocked the maturation of sterol regulatory element-binding protein (SREBP)-1 and SREBP-2 proteins and decreased the expression of multiple SREBP target genes, including and . Consistent with proprotein convertase subtilisin/kexin type 9 (PCSK9) reduction, both low-density lipoprotein receptor protein at the cell surface and low-density lipoprotein particle uptake were increased.

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In Duchenne muscular dystrophy (DMD), NF-κB is activated in skeletal muscle from infancy regardless of the underlying dystrophin mutation and drives inflammation and muscle degeneration while inhibiting muscle regeneration. Edasalonexent (CAT-1004) is a bifunctional orally administered small molecule that covalently links 2 compounds known to inhibit NF-κB, salicylic acid and docosahexaenoic acid (DHA). Edasalonexent is designed to inhibit activated NF-κB upon intracellular cleavage to these bioactive components.

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Duchenne muscular dystrophy (DMD) is a devastating muscle disease characterized by progressive muscle deterioration and replacement with an aberrant fatty, fibrous matrix. Chronic upregulation of nuclear factor κB (NF-κB) is implicated as a driver of the dystrophic pathogenesis. Herein, 2 members of a novel class of NF-κB inhibitors, edasalonexent (formerly CAT-1004) and CAT-1041, were evaluated in both mouse and golden retriever muscular dystrophy (GRMD) dog models of DMD.

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This report describes the synthesis and preliminary biological characterization of novel fatty acid niacin conjugates and fatty acid salicylate conjugates. These molecular entities were created by covalently linking two bioactive molecules, either niacin or salicylic acid, to an omega-3 fatty acid. This methodology allows the simultaneous intracellular delivery of two bioactives in order to elicit a pharmacological response that could not be replicated by administering the bioactives individually or in combination.

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We investigated the variation of N:P and N:K ratio in ombrotrophic Sphagnum plants along a gradient of atmospheric N deposition from 1 to 2.5 g m(-2) year(-1) in Central-East Europe. The N:P and N:K ratio in Sphagnum capitula increased significantly along the N deposition gradient.

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SIRT3 is a major mitochondrial NAD(+)-dependent protein deacetylase playing important roles in regulating mitochondrial metabolism and energy production and has been linked to the beneficial effects of exercise and caloric restriction. SIRT3 is emerging as a potential therapeutic target to treat metabolic and neurological diseases. We report the first sets of crystal structures of human SIRT3, an apo-structure with no substrate, a structure with a peptide containing acetyl lysine of its natural substrate acetyl-CoA synthetase 2, a reaction intermediate structure trapped by a thioacetyl peptide, and a structure with the dethioacetylated peptide bound.

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SIRT1 is an NAD(+)-dependent protein deacetylase that appears to produce beneficial effects on metabolic parameters such as glucose and insulin homeostasis. Activation of SIRT1 by resveratrol (1) has been shown to modulate insulin resistance, increase mitochondrial content and prolong survival in lower organisms and in mice on a high fat diet. Herein, we describe the identification and SAR of a series of oxazolo[4,5-b]pyridines as novel small molecule activators of SIRT1 which are structurally unrelated to and more potent than resveratrol.

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Background: Calorie restriction (CR) produces a number of health benefits and ameliorates diseases of aging such as type 2 diabetes. The components of the pathways downstream of CR may provide intervention points for developing therapeutics for treating diseases of aging. The NAD+-dependent protein deacetylase SIRT1 has been implicated as one of the key downstream regulators of CR in yeast, rodents, and humans.

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SIRT3 is a key mitochondrial protein deacetylase proposed to play key roles in regulating mitochondrial metabolism but there has been considerable debate about its actual size, the sequences required for activity, and its subcellular localization. A previously cloned mouse SIRT3 has high sequence similarity with the C-terminus of human SIRT3 but lacks an N-terminal mitochondrial targeting sequence and has no detectable deacetylation activity in vitro. Using 5' rapid amplification of cDNA ends, we cloned the entire sequence of mouse SIRT3, as well as rat and rabbit SIRT3.

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A series of imidazo[1,2-b]thiazole derivatives is shown to activate the NAD(+)-dependent deacetylase SIRT1, a potential new therapeutic target to treat various metabolic disorders. This series of compounds was derived from a high throughput screening hit bearing an oxazolopyridine core. Water-solubilizing groups could be installed conveniently at either the C-2 or C-3 position of the imidazo[1,2-b]thiazole ring.

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A series of triamide derivatives bearing a benzothiazole core is shown to be potent microsomal triglyceride transfer protein (MTP) inhibitors. In order to minimize liver toxicity, these compounds have been optimized to have activity only in the enterocytes and have limited systemic bioavailability. Upon oral administration, selected analogs within this series have been further demonstrated to reduce food intake along with body weight and thereby improve glucose homeostasis and insulin sensitivity in a 28-day mice diet-induced obesity (DIO) model.

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SIRT1 is a prominent member of a family of NAD(+)-dependent enzymes and affects a variety of cellular functions ranging from gene silencing, regulation of the cell cycle and apoptosis, to energy homeostasis. In mature adipocytes, SIRT1 triggers lipolysis and loss of fat content. However, the potential effects of SIRT1 on insulin signaling pathways are poorly understood.

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Sirtuins represent a novel family of enzymes that are collectively well situated to help regulate nutrient sensing and utilization, metabolic rate and ultimately metabolic disease. Activation of one of these enzymes, SIRT1, leads to enhanced activity of multiple proteins, including peroxisome-proliferator activated receptor coactivator-1alpha (PGC-1alpha), which helps to mediate some of the in vitro and in vivo effects of sirtuins. As such, enhanced SIRT1 activity decreases glucose levels, improves insulin sensitivity, increases mitochondrial number and function, decreases adiposity, improves exercise tolerance and potentially lowers body weight.

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Calorie restriction extends lifespan and produces a metabolic profile desirable for treating diseases of ageing such as type 2 diabetes. SIRT1, an NAD+-dependent deacetylase, is a principal modulator of pathways downstream of calorie restriction that produce beneficial effects on glucose homeostasis and insulin sensitivity. Resveratrol, a polyphenolic SIRT1 activator, mimics the anti-ageing effects of calorie restriction in lower organisms and in mice fed a high-fat diet ameliorates insulin resistance, increases mitochondrial content, and prolongs survival.

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Guided by X-ray crystallography, we have extended the structure-activity relationship (SAR) study on an isoxazole carboxylic acid-based PTP1B inhibitor (1) and more potent and equally selective (>20-fold selectivity over the highly homologous T-cell PTPase, TCPTP) PTP1B inhibitors were identified. Inhibitor 7 demonstrated good cellular activity against PTP1B in COS 7 cells.

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Protein tyrosine phosphatase 1B (PTP1B) inhibition increases insulin sensitivity and normalizes blood glucose levels in animals. The molecular events associated with PTP1B inhibition that increase insulin sensitivity remain controversial. Insulin resistant, diabetic ob/ob mice, dosed with PTP1B antisense for 3 weeks exhibited a decrease in PTP1B protein levels and a change in the expression level of p85alpha isoforms in liver, characterized by a reduction in p85alpha and an upregulation of the p50alpha and p55alpha isoforms.

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Monoacid-based PTP1B inhibitors with improved physiochemical properties have been investigated. A (2-hydroxy-phenoxy) acetic acid-based phosphotyrosyl mimetic has been linked with an optimized second arylphosphate binding site ligand to produce compound 20 with low micromolar potency against PTP1B, good selectivity over TCPTP (20-fold) and high cell permeability in the Caco-2 system.

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Using an NMR-based fragment screening and X-ray crystal structure-based assembly, starting with millimolar ligands for both the catalytic site and the second phosphotyrosine binding site, we have identified a small-molecule inhibitor of protein tyrosine phosphatase 1B with low micromolar inhibition constant, high selectivity (30-fold) over the highly homologous T-cell protein tyrosine phosphatase, and good cellular activity in COS-7 cells.

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A salicylate second site binder was linked to three classes of phosphotyrosine mimetics to produce potent protein tyrosine phosphatase 1B (PTP1B) inhibitors which exhibit significant selectivity against other phosphatases including the most homologous member, TCPTP.

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Protein tyrosine phosphatase (PTPase) 1B (PTP1B) has been implicated as a key negative regulator of both insulin and leptin signaling cascades. We identified several salicylic acid-based ligands for the second phosphotyrosine binding site of PTP1B using a NMR-based screening. Structure-based linking with a catalytic site-directed oxalylarylaminobenzoic acid-based pharmacophore led to the identification of a novel series of potent PTP1B inhibitors exhibiting 6-fold selectivity over the highly homologous T-cell PTPase (TCPTP) and high selectivity over other phosphatases.

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