Long-term peritoneal dialysis is associated with the development of peritoneal membrane alterations, both in morphology and function. Impaired ultrafiltration (UF) is the most important functional change, and peritoneal fibrosis is the major morphological alteration. Both are caused by the continuous exposure to dialysis solutions that are different from plasma water with regard to the buffer substance and the extremely high-glucose concentrations. Glucose has been incriminated as the major cause of long-term peritoneal membrane changes, but the precise mechanism has not been identified. We argue that glucose causes the membrane alterations by peritoneal pseudohypoxia and by the formation of advanced glycosylation end products (AGEs). After a summary of UF kinetics including the role of glucose transporters (GLUT), and a discussion on morphologic alterations, relationships between function and morphology and a survey of the pathogenesis of UF failure (UFF), it will be argued that impaired UF is partly caused by a reduction in small pore fluid transport as a consequence of AGE-related vasculopathy and - more importantly - in diminished free water transport due to pseudohypoxia, caused by increased peritoneal cellular expression of GLUT-1. The metabolism of intracellular glucose will be reviewed. This occurs in the glycolysis and in the polyol/sorbitol pathway, the latter is activated in case of a large supply. In both pathways the ratio between the reduced and oxidised form of nicotinamide dinucleotide (NADH/NAD+ ratio) will increase, especially because normal compensatory mechanisms may be impaired, and activate expression of hypoxia-inducible factor-1 (HIF-1). The latter gene activates various profibrotic factors and GLUT-1. Besides replacement of glucose as an osmotic agent, medical treatment/prevention is currently limited to tamoxifen and possibly Renin/angiotensis/aldosteron (RAA) inhibitors.

• Klíčová slova
• AGE, GLUT-1, HIF-1, glucose, membrane changes, peritoneal dialysis, pseudohypoxia, ultrafiltration impairment,
• MeSH
• dialyzační roztoky škodlivé účinky   metabolismus   MeSH
• glukosa škodlivé účinky   metabolismus   MeSH
• glykosylace MeSH
• lidé MeSH
• peritoneální dialýza * škodlivé účinky   MeSH
• peritoneum metabolismus   MeSH
• ultrafiltrace MeSH
• voda metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• dialyzační roztoky MeSH
• glukosa MeSH
• voda MeSH

In this study, we investigated the clinical effects of blood ultrafiltration therapy in patients with acute decompensated chronic heart failure. We enrolled 78 patients with acute decompensated chronic heart failure who were admitted to a hospital from September 2017 to December 2021, and divided them into two groups based on the digital randomization method. The FQ-16 heart failure ultrafiltration dehydrating device blood ultrafiltration therapy was administered to the observation group (39 patients) for 8-16 hours, while the control group (39 patients) received the stepped drug therapy. Echocardiography was used to assess the changes in cardiac function of the patients in both groups before and after treatment. The changes in urine volume, N-terminal pro-B-type natriuretic peptide (NT-proBNP), plasma renin, and serum creatinine levels were measured before and after the treatment to compare the overall response rate of the patients in both groups. The differences in left ventricular end-systolic dimension and left ventricular end-diastolic dimension and the ejection fraction between the groups before treatment were not statistically significant (P > 0.05), however, the left ventricular end-diastolic dimension in the observation group was significantly lower and the ejection fraction was significantly higher (P < 0.05) compared with that before treatment; the urine volume, N-terminal pro-B-type natriuretic peptide (NT-proBNP), plasma renin, and serum creatinine were significantly improved in both groups after treatment compared with that before treatment. All indexes in the observation group were better than those in the control group (P < 0.05), 74.36%. The overall response rate of the observation group was 94.87%, x2 = 4.843 and the difference between groups was statistically significant (P < 0.05). Blood ultrafiltration therapy for patients with acute decompensated chronic heart failure can improve their cardiac and renal functions, reduce NT-proBNP, reduce volume load, and enhance efficacy while ensuring high safety.

• MeSH
• biologické markery MeSH
• diuretika terapeutické užití   MeSH
• funkce levé komory srdeční fyziologie   MeSH
• kreatinin MeSH
• lidé MeSH
• natriuretický peptid typu B * MeSH
• peptidové fragmenty MeSH
• renin MeSH
• srdeční selhání * MeSH
• tepový objem fyziologie   MeSH
• ultrafiltrace MeSH
• výsledek terapie MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• biologické markery MeSH
• diuretika MeSH
• kreatinin MeSH
• natriuretický peptid typu B * MeSH
• peptidové fragmenty MeSH
• renin MeSH

To date, according to the latest literature inputs, membranes-based technologies (microfiltration, ultrafiltration and nanofiltration) have demonstrated to meet the recovery of biologically active compounds, mainly phenolic compounds and their derivatives, from agro-food products and by-products. The goal of this paper is to provide a critical overview of the on ongoing development works aimed at improving the separation, fractionation and concentration of phenolic compounds and their derivatives from their original sources. The literature data are analyzed and discussed in relation to separation processes, molecule properties, membrane characteristics and key factors affecting the performance of such technologies. Technological advances and improvements over conventional technologies, as well as critical aspects to be further investigated are highlighted and discussed. Finally, a critical outlook about the current status for a large-scale application and the role of these processes from an environmental viewpoint is provided.

• Klíčová slova
• Phenolic compounds, agro-food by-products, foods, nanofiltration, ultrafiltration,
• MeSH
• analýza potravin MeSH
• chemická frakcionace MeSH
• fenoly * izolace a purifikace   MeSH
• membrány umělé * MeSH
• potravinářská technologie * metody   trendy   MeSH
• ultrafiltrace * MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• fenoly * MeSH
• membrány umělé * MeSH

Pressure-driven membrane-based technologies represent a valid approach to reduce the environmental pollution of several agro-food by-products. Recently, in relation to the major interest for natural compounds with biological activities, their use has been also addressed to the recovery, separation and fractionation of phenolic compounds from such by-products. In particular, tight ultrafiltration (UF) and nanolfiltration (NF) membranes have been recognized for their capability to recover phenolic compounds from several types of agro-food by-products. The separation capability of these membranes, as well as their productivity, depends on multiple factors such as membrane material, molecular weight cut-off (MWCO) and operating conditions (e.g., pressure, temperature, feed flow rate, volume reduction factor, etc.). This paper aims at providing a critical overview of the influence of these parameters on the recovery of phenolic compounds from agro-food by-products by using tight UF and NF membranes. The literature data are analyzed and discussed in relation to separation processes, molecule properties, membrane characteristics and other phenomena occurring in the process. Current extraction methodologies of phenolic compounds from raw materials are also introduced in order to drive the implementation of integrated systems for the production of actractive phenolic formulations of potential interest as food antioxidants.

• Klíčová slova
• agro-food by-products, biologically active compounds, nanofiltration, polyphenols, ultrafiltration,
• MeSH
• analýza potravin MeSH
• membrány umělé * MeSH
• molekulární struktura MeSH
• nanotechnologie * MeSH
• polyfenoly * analýza   chemie   MeSH
• potraviny MeSH
• ultrafiltrace * metody   MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• membrány umělé * MeSH
• polyfenoly * MeSH

Typically, the various agro-food by-products of the food industry are treated by standard membrane processes, such as microfiltration, ultrafiltration and nanofiltration, in order to prepare them for final disposal. Recently, however, new membrane technologies have been developed. The recovery, separation and fractionation of high-added-value compounds, such as phenolic compounds from food processing waste, are major current research challenges. The goal of this paper is to provide a critical review of the main agro-food by-products treated by membrane technologies for the recovery of nutraceuticals. State-of-the-art of developments in the field are described. Particular attention is paid to experimental results reported for the recovery of polyphenols and their derivatives of different molecular weight. The literature data are analyzed and discussed in relation to separation processes, molecule properties, membrane characteristics and other interesting phenomena that occur during their recovery.

• Klíčová slova
• High added value compounds, Membrane technology, Nutraceuticals, Recovery, Wastes,
• MeSH
• chemická frakcionace MeSH
• fenoly analýza   MeSH
• manipulace s potravinami MeSH
• molekulová hmotnost MeSH
• polyfenoly analýza   MeSH
• potravinářský průmysl MeSH
• potravní doplňky MeSH
• průmyslový odpad analýza   MeSH
• ultrafiltrace MeSH
• zemědělské plodiny chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• fenoly MeSH
• polyfenoly MeSH
• průmyslový odpad MeSH

In this article, a portable device was presented for continual measuring of equilibrium equivalent concentration (EEC) of (222)Rn based on the Timepix detector with 300-µm-thick active layer. In order to have a portable device, a filtration head was developed for collecting short-lived radon progenies attached on aerosols. The short-lived progenies are estimated from analysing alphas from decay of (218,214)Po from Millipore filter after termination of filtration. Comparison with beta measurement was done as well. The dependence of EEC on an air flow and filtration time was studied. The low-level detection limit for EEC was estimated from the last 10 min of 3-h decay measurement and was found in the range of 40-70 Bq m(-3). EEC was measured in National Radiation Protection Institute radon chamber, and results were compared with the commercial detector Fritra4.

• MeSH
• aerosoly MeSH
• alfa částice MeSH
• analogově digitální konverze MeSH
• beta částice MeSH
• dceřiné produkty radonu analýza   MeSH
• design vybavení MeSH
• křemík MeSH
• monitorování radiace přístrojové vybavení   metody   MeSH
• počítačové zpracování signálu MeSH
• radioaktivní látky znečišťující vzduch analýza   MeSH
• radon analýza   MeSH
• ultrafiltrace MeSH
• znečištění vzduchu ve vnitřním prostředí analýza   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• aerosoly MeSH
• dceřiné produkty radonu MeSH
• křemík MeSH
• radioaktivní látky znečišťující vzduch MeSH
• radon MeSH

Two fast, simple, selective and economical sample preparation methods for the determination of entecavir in biological materials available at low amounts are reported. The choice of optimal extraction techniques was performed with regard to analyte hydrophilicity, sample volumes, selectivity, method recovery and rapidity. The compatibility of the eluate with the hydrophilic interaction chromatography (HILIC) mobile phase was crucial to allow the elimination of the evaporation and reconstitution steps and to obtain acceptable peak shapes. Different types of sorbents were employed for the extraction of two biological materials (plasma and plasma ultrafiltrate). The mixed-mode polymeric sorbent MCX was chosen as a suitable one for the solid phase extraction (SPE) of plasma samples. The analytes were eluted with 1ml of the mixture of 5 % ammonium hydroxide in ACN:water (95:5). Protein precipitation (PP) with 1ml of ACN was used to remove proteins from 500μl of plasma sample prior to SPE extraction. The microextraction by packed sorbent (MEPS) was employed for the cleaning up of plasma ultrafiltrate samples due to very small volumes available for the analysis. MEPS implemented a novel sorbent based on porous graphitic carbon, semi-automatic analytical syringe and a small volume of sample (50μl). The elution step was performed using 100μl of the mixture of 5mM ammonium acetate pH 4.0:ACN (25:75). The MEPS eluate was fully compatible with HILIC mobile phase subsequently used for the analysis of entecavir, unlike SPE eluate, which had to be evaporated and reconstituted in mobile phase. Both analytical methods were validated and demonstrated good linearity in a range 1-100ng/ml (r(2)>0.9992) for plasma samples and in a range 0.5-100ng/ml (0.9991) for the plasma ultrafiltrate samples. Intra-day accuracy expressed as recovery was within the range from 80-98% for the plasma samples and 97-106% for the plasma ultrafiltrate samples. Inter-day accuracy ranged within 81-106% for the plasma and 95-101% for the plasma ultrafiltrate samples. The intra-day precision expressed as the % of RSD was lower than 4% for both matrices and inter-day precision was lower than 7% for plasma and lower than 17% for plasma ultrafiltrate. Method sensitivity reached LLOQ of 1ng/ml in plasma and 0.5ng/ml in plasma ultrafiltrate samples. The method was applied for the determination of concentration-time profiles of entecavir in plasma of the perfusate for rat kidney perfusion and for the measurement of concentration of entecavir in plasma ultrafiltrate samples. The results should be helpful in the evaluation of excretion mechanism of entecavir.

• Klíčová slova
• Antivirals, Hydrophilic compounds, MEPS, Porous graphitic carbon, Sample preparation,
• MeSH
• acetonitrily chemie   MeSH
• adsorpce MeSH
• antivirové látky krev   farmakokinetika   MeSH
• chemické techniky analytické MeSH
• chromatografie MeSH
• guanin analogy a deriváty   krev   farmakokinetika   MeSH
• hydrofobní a hydrofilní interakce MeSH
• krysa rodu Rattus MeSH
• limita detekce MeSH
• mikroextrakce na pevné fázi MeSH
• potkani Wistar MeSH
• referenční standardy MeSH
• reprodukovatelnost výsledků MeSH
• rozpouštědla MeSH
• tandemová hmotnostní spektrometrie MeSH
• ultrafiltrace MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• acetonitrile MeSH Prohlížeč
• acetonitrily MeSH
• antivirové látky MeSH
• entecavir MeSH Prohlížeč
• guanin MeSH
• rozpouštědla MeSH

Many articles have been published on coagulant dosing in membrane bioreactors, though few have been long-term studies examining the treatment of real wastewater. This study summarises the results of a membrane bioreactor pilot-plant (flat sheet membrane, nominal pore size 0.03 μm) that treated real municipal wastewater for two-years. Both influence of phosphorus precipitation by ferric sulphate on membrane permeability (flux decrease) and soluble microbial product concentration (especially on carbohydrates and proteins) were monitored. Flux decrease over work cycles lasting several months without phosphorus precipitation were compared to two periods with precipitation. X-ray elemental diffractometry of the filtration cake showed differences in the main contributors to inorganic fouling, with decreases in Ca and Si during operation with coagulant addition, and an increase in Fe.

• MeSH
• anaerobní bakterie metabolismus   MeSH
• analýza selhání vybavení MeSH
• bioreaktory mikrobiologie   MeSH
• chemické látky znečišťující vodu izolace a purifikace   metabolismus   MeSH
• čištění vody přístrojové vybavení   MeSH
• design vybavení MeSH
• fosfor MeSH
• frakční precipitace MeSH
• membrány umělé * MeSH
• rozpustnost MeSH
• ultrafiltrace přístrojové vybavení   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chemické látky znečišťující vodu MeSH
• fosfor MeSH
• membrány umělé * MeSH

Membrane ultrafiltration (UF) was used in sample preparation of the culture fluids of the human intestinal bacterium Clostridium paraputrificum strain J4 containing seven extracellular chitinolytic isoenzymes (38-90 kDa). The subsequent filtration of the bacteria-free supernatants was carried out through Millipore membranes with cut-off 100 and 30 kDa for separation of undigested components of the culture medium and bacterial metabolites with molecular weight higher and lower than that of the target enzymes. The chitinolytic enzymes, which were the minor components in the culture fluids, were concentrated at UF as well. The aim of the research consisted in evaluation of the effect of component composition of bacteria-free supernatants and the chemical nature of membrane active layer on partial fractionation of the chitinolytic enzymes, their recovery in retentates and purification degree. On the basis of the obtained experimental results, the sample preparation procedure of the culture fluids of C. paraputrificum J4 was established to be used further in chromatographic separations of the chitinolytic enzymes.

• MeSH
• bakteriální proteiny izolace a purifikace   metabolismus   MeSH
• chitinasy izolace a purifikace   metabolismus   MeSH
• Clostridium enzymologie   růst a vývoj   MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• kultivační média MeSH
• lidé MeSH
• membrány umělé MeSH
• průmyslová mikrobiologie MeSH
• střeva mikrobiologie   MeSH
• ultrafiltrace metody   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• bakteriální proteiny MeSH
• chitinasy MeSH
• kultivační média MeSH
• membrány umělé MeSH

BACKGROUND: The incidence of food allergy to wheat is increasing. Its diagnosis depends on the purity of major allergens and their inclusion in tests. Isolation and characterization of wheat allergens are therefore of utmost importance. OBJECTIVE: To purify and identify wheat flour allergens most frequently recognized by patients' IgE antibodies and to study their allergenicity. METHODS: Water/salt-soluble extracts from wheat flour were prepared and separated using a combination of ultrafiltration, isoelectric focusing and liquid chromatography. Purified proteins were analysed by immunoblotting using pooled sera from patients with atopic dermatitis who possessed IgE specific to wheat. Wheat proteins found to bind IgE were subsequently identified by matrix-assisted laser desorption/ionisation-time of flight mass spectrometry. The frequency and intensity of IgE binding of isolated proteins were tested using individual sera from patients and controls. RESULTS: We developed a procedure that allows isolation of wheat allergens from natural sources. Twenty-seven potential wheat allergens have been successfully identified; of these, the following seven are newly reported in food allergy: endogenous α-amylase/subtilisin inhibitor, trypsin/α-amylase inhibitor (AAI) CMX1/CMX3, thaumatin-like protein (TLP), xylanase inhibitor protein-1, β-glucosidase, class II chitinase and 26 kDa endochitinase. TLP and wheatwin were shown to activate patients' basophils to a similar extent as two well-known allergens, lipid transfer protein (Tri a 14) and AAI 0.19 (Tri a 28.0101). CONCLUSION AND CLINICAL RELEVANCE: Our new approach enables the isolation of water/salt-soluble wheat allergens in their native form in amounts sufficient both for biological testing (in vivo and in vitro) and for physicochemical characterization. Such studies will lead to a more detailed knowledge of allergenicity of wheat proteins and to improved accuracy of diagnostic tests.

• MeSH
• alergeny chemie   imunologie   izolace a purifikace   MeSH
• alergie na pšenici diagnóza   imunologie   MeSH
• atopická dermatitida diagnóza   imunologie   MeSH
• bazofily imunologie   MeSH
• dítě MeSH
• dospělí MeSH
• imunoglobulin E krev   MeSH
• isoelektrická fokusace MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mouka analýza   MeSH
• potravinová alergie diagnóza   imunologie   MeSH
• předškolní dítě MeSH
• pšenice chemie   imunologie   MeSH
• rostlinné proteiny chemie   imunologie   izolace a purifikace   MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• ultrafiltrace MeSH
• vysokoúčinná kapalinová chromatografie MeSH
• Check Tag
• dítě MeSH
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladiství MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• předškolní dítě MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• alergeny MeSH
• imunoglobulin E MeSH
• rostlinné proteiny MeSH