The aim of this study is to evaluate opportunistic pathogenic bacteria of the genus Pseudomonas in anthropogenically impacted bathing waters, primarily focusing on bathing ponds. The findings include the detection of these bacteria, their susceptibility to selected antibiotics, and the determination of the Exotoxin A (exoA) gene using PCR method. P. aeruginosa was present in most samples, albeit in low concentrations (1-14 CFU/100 mL). The presence of P. otitidis, which is associated with ear infection, in this type of bathing water, was not rare (up to 90 CFU/100 mL). This species would not be detected by the standard methods, including tests on acetamid medium, used for P. aeruginosa in water. The isolated strains of P. otitidis lack the exoA gene and exhibited higher resistance to meropenem compared to P. aeruginosa.

• MeSH
• ADP-ribosatransferasy genetika   MeSH
• antibakteriální látky * farmakologie   MeSH
• bakteriální léková rezistence MeSH
• bakteriální proteiny genetika   MeSH
• bakteriální toxiny genetika   MeSH
• exotoxin A z Pseudomonas aeruginosa MeSH
• exotoxiny genetika   MeSH
• faktory virulence genetika   MeSH
• mikrobiální testy citlivosti * MeSH
• mikrobiologie vody * MeSH
• polymerázová řetězová reakce MeSH
• Pseudomonas * genetika   izolace a purifikace   klasifikace   účinky léků   MeSH
• rybníky * mikrobiologie   MeSH
• Publikační typ
• časopisecké články MeSH

Publikace obsahuje úplné znění aktuálních českých zákonů a právních předpisů, které se zaměřují na různé poplatky. Určeno odborné veřejnosti.

• MeSH
• poplatky a výdaje MeSH
• rozhlas MeSH
• soudní vědy MeSH
• televize MeSH
• Geografické názvy
• Česká republika MeSH

• Konspekt
• Veřejné finance
• NLK Obory
• právo, zákonodárství
• ekonomie, ekonomika, ekonomika zdravotnictví
• NLK Publikační typ
• zákony
• právní předpisy

Dolichol is a lipid critical for N-glycosylation as a carrier for activated sugars and nascent oligosaccharides. It is commonly thought to be directly produced from polyprenol by the enzyme SRD5A3. Instead, we found that dolichol synthesis requires a three-step detour involving additional metabolites, where SRD5A3 catalyzes only the second reaction. The first and third steps are performed by DHRSX, whose gene resides on the pseudoautosomal regions of the X and Y chromosomes. Accordingly, we report a pseudoautosomal-recessive disease presenting as a congenital disorder of glycosylation in patients with missense variants in DHRSX (DHRSX-CDG). Of note, DHRSX has a unique dual substrate and cofactor specificity, allowing it to act as a NAD+-dependent dehydrogenase and as a NADPH-dependent reductase in two non-consecutive steps. Thus, our work reveals unexpected complexity in the terminal steps of dolichol biosynthesis. Furthermore, we provide insights into the mechanism by which dolichol metabolism defects contribute to disease.

• MeSH
• 3-oxo-5-alfa-steroid-4-dehydrogenasa metabolismus   genetika   MeSH
• dolichol * metabolismus   biosyntéza   MeSH
• glykosylace MeSH
• lidé MeSH
• membránové proteiny metabolismus   genetika   MeSH
• missense mutace MeSH
• vrozené poruchy glykosylace metabolismus   genetika   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Publikace obsahuje úplné znění aktuálních českých zákonů a právních předpisů, které se zaměřují na různé poplatky. Určeno odborné veřejnosti.

• MeSH
• poplatky a výdaje zákonodárství a právo   MeSH
• veřejný sektor zákonodárství a právo   MeSH
• Geografické názvy
• Česká republika MeSH

• Konspekt
• Veřejné finance
• NLK Obory
• právo, zákonodárství
• ekonomie, ekonomika, ekonomika zdravotnictví
• NLK Publikační typ
• zákony
• právní předpisy

Aldo-keto reductase 1C3 (AKR1C3) catalyzes the reduction of androstenedione to testosterone and reduces the effectiveness of chemotherapeutics. AKR1C3 is a target for treatment of breast and prostate cancer and AKR1C3 inhibition could be an effective adjuvant therapy in the context of leukemia and other cancers. In the present study, steroidal bile acid fused tetrazoles were screened for their ability to inhibit AKR1C3. Four C24 bile acids with C-ring fused tetrazoles were moderate to strong AKR1C3 inhibitors (37-88% inhibition), while B-ring fused tetrazoles had no effect on AKR1C3 activity. Based on a fluorescence assay in yeast cells, these four compounds displayed no affinity for estrogen receptor-α, or the androgen receptor, suggesting a lack of estrogenic or androgenic effects. A top inhibitor showed specificity for AKR1C3 over AKR1C2, and inhibited AKR1C3 with an IC50 of ∼7 μM. The structure of AKR1C3·NADP+ in complex with this C-ring fused bile acid tetrazole was determined by X-ray crystallography at 1.4 Å resolution, revealing that the C24 carboxylate is anchored to the catalytic oxyanion site (H117, Y55); meanwhile the tetrazole interacts with a tryptophan (W227) important for steroid recognition. Molecular docking predicts that all four top AKR1C3 inhibitors bind with nearly identical geometry, suggesting that C-ring bile acid fused tetrazoles represent a new class of AKR1C3 inhibitors.

• Publikační typ
• časopisecké články MeSH

Publikace obsahuje úplné znění aktuálních českých zákonů a předpisů, které se týkají veřejných poplatků. Určeno odborné veřejnosti.; Všechny poplatkové zákony byly od minulého vydání novelizovány: zákon o správních poplatcích má 12 větších i menších novel, zákon o místních poplatcích má 2 novelizace, soudní poplatky se měnily dvakrát. Dále jsou zde předpisy upravující poplatky rozhlasové a televizní, za znečišťování ovzduší, za činnost organizací státního odborného dohledu, za odebíranou přírodní minerální vodu, za znečištění vod a vypouštění odpadních vod, za udržování patentů, puncovní poplatky, zpoplatnění pozemních komunikací a další. Všechny změny jsou vyznačeny tučným písmem.

• MeSH
• místní státní správa MeSH
• poplatky a výdaje zákonodárství a právo   MeSH
• soudní vědy zákonodárství a právo   MeSH
• veřejný sektor zákonodárství a právo   MeSH
• Geografické názvy
• Česká republika MeSH

• Konspekt
• Veřejné finance
• NLK Obory
• právo, zákonodárství
• ekonomie, ekonomika, ekonomika zdravotnictví
• NLK Publikační typ
• zákony
• právní předpisy

Sperm metabolism is fundamental to sperm motility and male fertility. Its measurement is still in its infancy, and recommendations do not exist as to whether or how to standardize laboratory procedures. Here, using the sperm of an insect, the common bedbug, Cimex lectularius, we demonstrate that standardization of sperm metabolism is required with respect to the artificial sperm storage medium and a natural medium, the seminal fluid. We used fluorescence lifetime imaging microscopy (FLIM) in combination with time-correlated single-photon counting (TCSPC) to quantify sperm metabolism based on the fluorescent properties of autofluorescent coenzymes, NAD(P)H and flavin adenine dinucleotide. Autofluorescence lifetimes (decay times) differ for the free and protein-bound state of the co-enzymes, and their relative contributions to the lifetime signal serve to characterize the metabolic state of cells. We found that artificial storage medium and seminal fluid separately, and additively, affected sperm metabolism. In a medium containing sugars and amino acids (Grace's Insect medium), sperm showed increased glycolysis compared with a commonly used storage medium, phosphate-buffered saline (PBS). Adding seminal fluid to the sperm additionally increased oxidative phosphorylation, likely reflecting increased energy production of sperm during activation. Our study provides a protocol to measure sperm metabolism independently from motility, stresses that protocol standardizations for sperm measurements should be implemented and, for the first time, demonstrates that seminal fluid alters sperm metabolism. Equivalent protocol standardizations should be imposed on metabolic investigations of human sperm samples.

• MeSH
• flavinadenindinukleotid * MeSH
• mikroskopie fluorescenční multifotonová MeSH
• motilita spermií MeSH
• NADP * MeSH
• spermie účinky léků   MeSH
• štěnice MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Significance: Mitochondria determine glucose-stimulated insulin secretion (GSIS) in pancreatic β-cells by elevating ATP synthesis. As the metabolic and redox hub, mitochondria provide numerous links to the plasma membrane channels, insulin granule vesicles (IGVs), cell redox, NADH, NADPH, and Ca2+ homeostasis, all affecting insulin secretion. Recent Advances: Mitochondrial redox signaling was implicated in several modes of insulin secretion (branched-chain ketoacid [BCKA]-, fatty acid [FA]-stimulated). Mitochondrial Ca2+ influx was found to enhance GSIS, reflecting cytosolic Ca2+ oscillations induced by action potential spikes (intermittent opening of voltage-dependent Ca2+ and K+ channels) or the superimposed Ca2+ release from the endoplasmic reticulum (ER). The ATPase inhibitory factor 1 (IF1) was reported to tune the glucose sensitivity range for GSIS. Mitochondrial protein kinase A was implicated in preventing the IF1-mediated inhibition of the ATP synthase. Critical Issues: It is unknown how the redox signal spreads up to the plasma membrane and what its targets are, what the differences in metabolic, redox, NADH/NADPH, and Ca2+ signaling, and homeostasis are between the first and second GSIS phase, and whether mitochondria can replace ER in the amplification of IGV exocytosis. Future Directions: Metabolomics studies performed to distinguish between the mitochondrial matrix and cytosolic metabolites will elucidate further details. Identifying the targets of cell signaling into mitochondria and of mitochondrial retrograde metabolic and redox signals to the cell will uncover further molecular mechanisms for insulin secretion stimulated by glucose, BCKAs, and FAs, and the amplification of secretion by glucagon-like peptide (GLP-1) and metabotropic receptors. They will identify the distinction between the hub β-cells and their followers in intact and diabetic states. Antioxid. Redox Signal. 36, 920-952.

• MeSH
• adenosintrifosfát metabolismus   MeSH
• beta-buňky * metabolismus   MeSH
• glukosa metabolismus   MeSH
• inzulin metabolismus   MeSH
• Langerhansovy ostrůvky * metabolismus   MeSH
• mitochondrie metabolismus   MeSH
• NAD metabolismus   MeSH
• NADP metabolismus   MeSH
• sekrece inzulinu MeSH
• sekretagoga metabolismus   MeSH
• vápník metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Sesquiterpene lactone helenalin is used as an antiphlogistic in European and Chinese folk medicine. The pharmacological activities of helenalin have been extensively investigated, yet insufficient information exists about its metabolic properties. The objectives of the present study were (1) to investigate the in vitro NADPH-dependent metabolism of helenalin (5 and 100 μM) using human and rat liver microsomes and liver cytosol, (2) to elucidate the role of human cytochrome P450 (CYP) enzymes in its oxidative metabolism, and (3) to study the inhibition of human CYPs by helenalin. Five oxidative metabolites were detected in NADPH-dependent human and rat liver microsomal incubations, while two reduced metabolites were detected only in NADPH-dependent human microsomal and cytosolic incubations. In human liver microsomes, the main oxidative metabolite was 14-hydroxyhelenalin, and in rat liver microsomes 9-hydroxyhelenalin. The overall oxidation of helenalin was several times more efficient in rat than in human liver microsomes. In humans, CYP3A4 and CYP3A5 followed by CYP2B6 were the main enzymes responsible for the hepatic metabolism of helenalin. The extrahepatic CYP2A13 oxidized helenalin most efficiently among CYP enzymes, possessing the Km value of 0.6 μM. Helenalin inhibited CYP3A4 (IC50 = 18.7 μM) and CYP3A5 (IC50 = 62.6 μM), and acted as a mechanism-based inhibitor of CYP2A13 (IC50 = 1.1 μM, KI = 6.7 μM, and kinact = 0.58 ln(%)/min). It may be concluded that the metabolism of helenalin differs between rats and humans, in the latter its oxidation is catalyzed by hepatic CYP2B6, CYP3A4, CYP3A5, and CYP3A7, and extrahepatic CYP2A13.

• MeSH
• druhová specificita MeSH
• inhibiční koncentrace 50 MeSH
• inhibitory cytochromu P450 aplikace a dávkování   metabolismus   farmakologie   MeSH
• jaterní mikrozomy metabolismus   MeSH
• krysa rodu rattus MeSH
• lidé MeSH
• NADP metabolismus   MeSH
• potkani Wistar MeSH
• seskviterpeny guajanové aplikace a dávkování   metabolismus   farmakologie   MeSH
• systém (enzymů) cytochromů P-450 účinky léků   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

BACKGROUND: Hexokinases (HKs) are well-studied enzymes catalyzing the first step of glycolysis. However, non-canonical regulatory roles of HKs are still incompletely understood. Here, we hypothesized that HKs comprise one of the missing links between high-dose metformin and the inhibition of the respiratory chain in cancer. METHODS: We tested the isoenzyme-specific regulatory roles of HKs in ovarian cancer cells by examining the effects of the deletions of HK1 and HK2 in TOV-112D ovarian adenocarcinoma cells. We reverted these effects by re-introducing wild-type HK1 and HK2, and we compared the HK1 revertant with the knock-in of catalytically dead HK1 p.D656A. We subjected these cells to a battery of metabolic and proliferation assays and targeted GC×GC-MS metabolomics. RESULTS: We found that the HK1 depletion (but not the HK2 depletion) sensitized ovarian cancer cells to high-dose metformin during glucose starvation. We confirmed that this newly uncovered role of HK1 is glycolysis-independent by the introduction of the catalytically dead HK1. The expression of catalytically dead HK1 stimulated similar changes in levels of TCA intermediates, aspartate and cysteine, and in glutamate as were induced by the HK2 deletion. In contrast, HK1 deletion increased the levels of branched amino acids; this effect was completely eliminated by the expression of catalytically dead HK1. Furthermore, HK1 revertants but not HK2 revertants caused a strong increase of NADPH/NADP ratios independently on the presence of glucose or metformin. The HK1 deletion (but not HK2 deletion) suppressed the growth of xenotransplanted ovarian cancer cells and nearly abolished the tumor growth when the mice were fed the glucose-free diet. CONCLUSIONS: We provided the evidence that HK1 is involved in the so far unknown glycolysis-independent HK1-metformin axis and influences metabolism even in glucose-free conditions.

• Publikační typ
• časopisecké články MeSH