Chloride Intracellular Channel (CLIC) family members uniquely transition between soluble and membrane-associated conformations. Despite decades of extensive functional and structural studies, CLICs' function as ion channels remains debated, rendering our understanding of their physiological role incomplete. Here, we expose the function of CLIC5 as a fusogen. We demonstrate that purified CLIC5 directly interacts with the membrane and induces fusion, as reflected by increased liposomal diameter and lipid and content mixing between liposomes. Moreover, we show that this activity is facilitated by acidic pH, a known trigger for CLICs' transition to a membrane-associated conformation, and that increased exposure of the hydrophobic inter-domain interface is crucial for this process. Finally, mutation of a conserved hydrophobic interfacial residue diminishes the fusogenic activity of CLIC5 in vitro and impairs excretory canal extension in C. elegans in vivo. Together, our results unravel the long-sought physiological role of these enigmatic proteins.
- MeSH
- Caenorhabditis elegans * genetika metabolismus MeSH
- chloridové kanály metabolismus MeSH
- chloridy * metabolismus MeSH
- liposomy MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
Analysis of Exhaled breath condensate (EBC) is a re-discovered approach to monitoring the course of the disease and reduce invasive methods of patient investigation. However, the major disadvantage and shortcoming of the EBC is lack of reliable and reproducible standardization of the method. Despite many articles published on EBC, until now there is no clear consensus on whether the analysis of EBC can provide a clue to diagnosis of the diseases. The purpose of this paper is to investigate our own method, to search for possible standardization and to obtain our own initial experience. Thirty healthy volunteers provided the EBC, in which we monitored the density, pH, protein, chloride and urea concentration. Our results show that EBC pH is influenced by smoking, and urea concentrations are affected by the gender of subjects. Age of subjects does not play a role. The smallest coefficient of variation between individual volunteers is for density determination. Current limitations of EBC measurements are the low concentration of many biomarkers. Standardization needs to be specific for each individual biomarker, with focusing on optimal condensate collection. EBC analysis has a potential become diagnostic test, not only for lung diseases.
- MeSH
- biologické markery analýza metabolismus MeSH
- chloridy analýza metabolismus MeSH
- dechové testy metody MeSH
- dospělí MeSH
- koncentrace vodíkových iontů MeSH
- kouření metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- močovina analýza metabolismus MeSH
- odběr biologického vzorku MeSH
- pilotní projekty MeSH
- proteiny analýza metabolismus MeSH
- referenční hodnoty MeSH
- referenční standardy MeSH
- senioři MeSH
- sexuální faktory MeSH
- věkové faktory MeSH
- zdraví dobrovolníci pro lékařské studie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
The effect of potassium (K) concentration gradient on stable caesium (Cs) uptake by Calla palustris was studied under hydroponic conditions after eight-day exposure in a greenhouse experiment. The plants were exposed to two different concentrations of Cs (provided as 0.5 and 1 mM CsCl) and five different concentrations of K (provided as K2SO4 in 0.5, 1, 2, 5, and 10 mM). The results indicate negative dependence of Cs uptake on K concentrations for both Cs treatments. The application of K reduced the transfer of stable Cs from water to plant by about 44-72% for 0.5 mM CsCl and 56-74% for 1 mM CsCl. The highest efficiency of Cs removal from water was observed for plants in K+ deficient solutions (plants starving), with an efficiency 8.0% for plants cultivated in 0.5 mM CsCl and 9.4% for plants in 1 mM CsCl. An increasing concentration of K also supported translocation of Cs from roots to leaves. Higher translocation was observed for the treatments with lower level of Cs, where the concentration of Cs in leaves became higher than that in roots. The Cs uptake and translocations were affected not only by the external concentration of K, but also the external concentration of stable Cs. A high concentration of K in the environment protects the food chain from Cs uptake by plants, but lowers the efficiency of phytoremediation techniques.
- MeSH
- biodegradace MeSH
- biologický transport účinky léků fyziologie MeSH
- Calla (rostlina) metabolismus MeSH
- cesium analýza metabolismus MeSH
- chloridy analýza metabolismus MeSH
- draslík metabolismus farmakologie MeSH
- kořeny rostlin chemie metabolismus MeSH
- listy rostlin chemie metabolismus MeSH
- radioaktivní látky znečišťující půdu MeSH
- radioizotopy cesia analýza metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
The Photosystem II reaction center is vulnerable to photoinhibition. The D1 and D2 proteins, lying at the core of the photosystem, are susceptible to oxidative modification by reactive oxygen species that are formed by the photosystem during illumination. Using spin probes and EPR spectroscopy, we have determined that both O2•- and HO• are involved in the photoinhibitory process. Using tandem mass spectroscopy, we have identified a number of oxidatively modified D1 and D2 residues. Our analysis indicates that these oxidative modifications are associated with formation of HO• at both the Mn4O5Ca cluster and the nonheme iron. Additionally, O2•- appears to be formed by the reduction of O2 at either PheoD1 or QA Early oxidation of D1:332H, which is coordinated with the Mn1 of the Mn4O5Ca cluster, appears to initiate a cascade of oxidative events that lead to the oxidative modification of numerous residues in the C termini of the D1 and D2 proteins on the donor side of the photosystem. Oxidation of D2:244Y, which is a bicarbonate ligand for the nonheme iron, induces the propagation of oxidative reactions in residues of the D-de loop of the D2 protein on the electron acceptor side of the photosystem. Finally, D1:130E and D2:246M are oxidatively modified by O2•- formed by the reduction of O2 either by PheoD1•- or QA•- The identification of specific amino acid residues oxidized by reactive oxygen species provides insights into the mechanism of damage to the D1 and D2 proteins under light stress.
- MeSH
- aminokyseliny chemie metabolismus MeSH
- antioxidancia metabolismus MeSH
- chloridy metabolismus MeSH
- elektronová paramagnetická rezonance MeSH
- fotosystém II - proteinový komplex chemie metabolismus MeSH
- hmotnostní spektrometrie MeSH
- hydroxylový radikál metabolismus MeSH
- kyslík metabolismus MeSH
- molekulární konformace MeSH
- molekulární modely MeSH
- oxidace-redukce * MeSH
- reaktivní formy kyslíku metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
This is the first report describing precipitation of bacteriophage particles with zinc chloride as a method of choice to isolate infectious lytic bacteriophages against Pectobacterium spp. and Dickeya spp. from environmental samples. The isolated bacteriophages are ready to use to study various (ecological) aspects of bacteria-bacteriophage interactions. The method comprises the well-known precipitation of phages from aqueous extracts of the test material by addition of ZnCl2, resuscitation of bacteriophage particles in Ringer's buffer to remove the ZnCl2 excess and a soft agar overlay assay with the host bacterium to isolate infectious individual phage plaques. The method requires neither an enrichment step nor other steps (e. g., PEG precipitation, ultrafiltration, or ultracentrifugation) commonly used in other procedures and results in isolation of active viable bacteriophage particles.
- MeSH
- bakteriofágy izolace a purifikace fyziologie MeSH
- časové faktory MeSH
- chloridy metabolismus MeSH
- Enterobacteriaceae virologie MeSH
- mikrobiologie životního prostředí * MeSH
- Pectobacterium virologie MeSH
- rostliny virologie MeSH
- sloučeniny zinku metabolismus MeSH
- virologie metody MeSH
- Publikační typ
- časopisecké články MeSH
Chronické nefropatie, které jsou spojeny s postupným úbytkem funkčních nefronů, se vyznačují poruchou ledvinové funkce. Ledvinovou funkcí je nejenom glomerulární filtrace, kterou u nemocných běžně vyšetřujeme jako clearance kreatininu nebo kalkulujeme na podkladě sérové koncentrace kreatininu, ale také funkce tubulární, která představuje tubulární resorpci a sekreci solutů. Tubulární transport solutů se v průběhu rozvoje ledvinové nedostatečnosti v důsledku adaptace významně mění a je ovlivněn řadou dalších faktorů, včetně farmakoterapie. Vyšetření tubulárního transportu solutů a správná interpretace výsledků má důležité konsekvence pro klinickou praxi.
Chronic nephropathies, which are associated with the gradual decline of functional nephrons, are characterised by impaired kidney function. Renal function is not only glomerular filtration rate, which we are assessing as creatinine clearance or calculating on the base of serum creatinine, but also a tubular function, which represents tubular resorption and secretion of solutes. Tubular solutes transport is significantly changed during the development of renal impairment as a result of the adaptation and is affected by a number of other factors, including pharmacotherapy. Examination of tubular transport and correct interpretation of results has the important impact on clinical practice.
- Klíčová slova
- (FE) vyšetření frakční exkrece solutů,
- MeSH
- chloridy izolace a purifikace metabolismus MeSH
- chronická renální insuficience * diagnóza metabolismus patofyziologie MeSH
- diagnostické techniky urologické využití MeSH
- draslík izolace a purifikace metabolismus MeSH
- elektrolyty izolace a purifikace metabolismus moč MeSH
- fosfáty izolace a purifikace metabolismus MeSH
- hodnoty glomerulární filtrace fyziologie účinky léků MeSH
- kreatinin izolace a purifikace krev metabolismus MeSH
- ledvinové kanálky fyziologie metabolismus patofyziologie MeSH
- lidé MeSH
- metabolická clearance fyziologie účinky léků MeSH
- moč fyziologie chemie MeSH
- nefrony metabolismus patofyziologie účinky léků MeSH
- sodík izolace a purifikace metabolismus MeSH
- statistika jako téma MeSH
- vyšetření funkce ledvin * metody využití MeSH
- Check Tag
- lidé MeSH
U jedinců s chronickým renálním onemocněním dochází v reziduálních nefronech ke snížení tubulární resorpce sodíku (TNa+) a chloridů (TCl–). Pokles TCl– je relativně menší než pokles TNa+. Tyto změny v tubulárním transportu Na+ a Cl– se podílejí na rozvoji poruch acidobazické rovnováhy u jedinců s poklesem glomerulární filtrace pod 0,5 ml/s/1,73 m2. Klíčová slova: sodík – chloridy – ledviny – tubulární resorpce
Tubular transport of sodium (TNa+) and chloride (TCl–) is decreased in patients with chronic kidney disease. The decrease of TCl– is relatively lower than that of TNa+. These changes of tubular transport of Na+ and Cl– participate on the development of acid base disturbance in patients with chronic kidney disease and with their glomerular filtration rate lower than 0.5 ml/s/1.73 m2. Keywords: sodium – chloride – kidney – tubular reabsorption
- MeSH
- chloridy * krev metabolismus MeSH
- chronické selhání ledvin * diagnóza etiologie krev MeSH
- dospělí MeSH
- hodnoty glomerulární filtrace MeSH
- lidé středního věku MeSH
- lidé MeSH
- poruchy acidobazické rovnováhy etiologie krev MeSH
- renální reabsorpce * fyziologie MeSH
- sodík * krev metabolismus MeSH
- statistika jako téma MeSH
- studie případů a kontrol MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
The analysis of an ionic profile of exhaled breath condensate (EBC) by capillary electrophoresis with contactless conductivity detection and double opposite end injection, is demonstrated. A miniature sampler made from a 2 ml syringe and an aluminium cooling cylinder was used for the fast collection of EBC (under one minute). Analysis of the collected EBC was performed in a 60 mM 2-(N-morpholino)ethanesulfonic acid, 60 mM L-histidine background electrolyte with 30 µM cetyltrimethylammonium bromide and 2 mM 18-crown-6 at pH 6, and excellent repeatability of migration times (RSD <1.3% (n = 7)) and peak areas (RSD < 7% (n = 7)) of 14 ions (inorganic anions, cations and organic acids) was obtained. It is demonstrated that the analysis of EBC samples obtained from patients with various respiratory diseases (chronic obstructive pulmonary disease, asthma, pulmonary fibrosis, sarcoidosis, cystic fibrosis) is possible in less than five minutes and the ionic profile can be compared with the group of healthy individuals. The analysis of the ionic profile of EBC samples provides a set of data in which statistically significant differences among the groups of patients could be observed for several clinically relevant anions (nitrite, nitrate, acetate, lactate). The developed collection system and method provides a highly reproducible and fast way of collecting and analyzing EBC, with future applicability in point-of-care diagnostics.
- MeSH
- acetáty analýza metabolismus MeSH
- amoniové sloučeniny analýza metabolismus MeSH
- bronchiální astma metabolismus MeSH
- butyráty analýza metabolismus MeSH
- chloridy analýza metabolismus MeSH
- chronická obstrukční plicní nemoc metabolismus MeSH
- crown ethery MeSH
- cystická fibróza metabolismus MeSH
- dechové testy přístrojové vybavení metody MeSH
- dospělí MeSH
- draslík analýza metabolismus MeSH
- dusičnany analýza metabolismus MeSH
- dusitany analýza metabolismus MeSH
- elektroforéza kapilární MeSH
- hořčík analýza metabolismus MeSH
- ionty MeSH
- koncentrace vodíkových iontů MeSH
- kyselina mléčná analýza metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- plicní fibróza metabolismus MeSH
- plicní sarkoidóza metabolismus MeSH
- propionáty analýza metabolismus MeSH
- senioři MeSH
- sírany analýza metabolismus MeSH
- sodík analýza metabolismus MeSH
- vápník analýza metabolismus MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A novel approach for diagnosis of cystic fibrosis is presented. A simple and fast procedure to obtain sweat sample was developed. It consists of repeatedly wiping the skin of the forearm with deionized water moisturized cotton swab and extraction in 1mL of deionized water. Double opposite end injection capillary electrophoresis with contactless conductometric detection is used for the analysis of the extract. Chloride, sodium and potassium as the three target ions that participate in the ion transfer across the cellular membranes, and are affected by CF, are simultaneously determined in approximately 3min in a background electrolyte containing 20mM 2-(N-morpholino)ethanesulfonic acid, 20mM l-histidine and 2mM 18-crown-6. By using the target ion ratios rather than the concentrations of each individual ion combined with principal component analysis, the diagnosis of CF can be made more accurately and greatly reduce the number of false positive or negative results as is often the case when single ion (chloride) is analyzed.
- MeSH
- analýza hlavních komponent MeSH
- chloridy metabolismus MeSH
- cystická fibróza diagnóza metabolismus MeSH
- draslík metabolismus MeSH
- elektroforéza kapilární metody MeSH
- falešně pozitivní reakce MeSH
- lidé MeSH
- pot metabolismus MeSH
- sodík metabolismus MeSH
- studie případů a kontrol MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Hydroxyl radical (HO•) production in photosystem II (PSII) was studied by electron paramagnetic resonance (EPR) spin-trapping technique. It is demonstrated here that the exposure of PSII membranes to heat stress (40 °C) results in HO• formation, as monitored by the formation of EMPO-OH adduct EPR signal. The presence of different exogenous halides significantly suppressed the EMPO-OH adduct EPR signal in PSII membranes under heat stress. The addition of exogenous acetate and blocker of chloride channel suppressed the EMPO-OH adduct EPR signal, whereas the blocker of calcium channel did not affect the EMPO-OH adduct EPR signal. Heat-induced hydrogen peroxide (H₂O₂) production was studied by amplex red fluorescent assay. The presence of exogenous halides, acetate and chloride blocker showed the suppression of H₂O₂ production in PSII membranes under heat stress. Based on our results, it is proposed that the formation of HO• under heat stress is linked to uncontrolled accessibility of water to the water-splitting manganese complex caused by the release of chloride ion on the electron donor side of PSII. Uncontrolled water accessibility to the water-splitting manganese complex causes the formation of H₂O₂ due to improper water oxidation, which leads to the formation of HO• via the Fenton reaction under heat stress.
- MeSH
- chloridy metabolismus MeSH
- elektronová paramagnetická rezonance metody MeSH
- fotosystém II - proteinový komplex chemie metabolismus MeSH
- hydroxylový radikál metabolismus MeSH
- oxidace-redukce MeSH
- peroxid vodíku farmakologie MeSH
- spin trapping metody MeSH
- Spinacia oleracea chemie MeSH
- vytápění MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH