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Bartonella quintana byla v sirsim povědomi lekařske veřejnosti předevsim pocatkem minuleho stoleti v souvislosti s výskytem tzv. zakopove horecky. V dnesni době se jedna o ne přilis casteho původce infekcni endokarditidy (IE) předevsim u pacientů se sniženou funkci imunitniho systemu. Zaludnosti teto bakterie je, že ve větsině připadů neni detekovatelna v hemokultuře, nebo až po velmi dlouhe kultivaci. Definitivni diagnozu se větsinou podaři urcit až na zakladě polymerazove řetězove reakce (PCR) z odebraneho chlopenniho materialu. Kazuistika prezentuje připad 69lete ženy přijate do intenzivni pece původně pro bronchopneumonii, u ktere byla diky rutinně provedenemu vstupnimu echokardiografickemu vysetřeni diagnostikovana těžka chlopenni vada a nasledně bartonellova endokarditida. Předkladana kazuistika se snaži vyzdvihnout význam rutinniho echokardiografickeho vysetřeni provaděneho intenzivistou‑nekardiologem a taktež upozornit na ne přilis castý připad kultivacně negativni endokarditidy.

Albumin je stale siroce studovaným proteinem lidskeho těla. Historicky nejdele je podavan jako objemova nahrada s využitim jeho onkotických vlastnosti. V oblasti tekutinove terapie je v poslednich letech dale srovnavan s ostatnimi typy roztoků v různých klinických indikacich a je sledovana zejmena jeho bezpecnost. Předmětem zajmu výzkumu jsou jeho dalsi biologicke ucinky, ktere jsou využivany ve specifických klinických situacich: jaterni selhani, prevence selhani ledvin, syndrom akutni respiracni tisně dospělých, traumaticke poskozeni mozku, ovarialni hyperstimulacni syndrom. Přehledový clanek shrnuje soucasný stav odborneho poznani a jeho využiti jak u dospělých pacientů v intenzivni peci, tak v neonatologii. Diskutuje vybrane klinicke syndromy a dosud znamou fyziologii albuminu v lidskem těle. Věnuje se tež použiti albuminu v postupech mimotělni podpory organových funkci: mimotělni oběh v kardiochirurgii, dialýza a plazmafereza.

Celoplicni lavaž velkým množstvim fyziologickeho roztoku je v soucasnosti zlatým standardem lecby plicni alveolarni proteinozy. Toto vzacne onemocněni charakterizovane akumulaci lipoproteinozniho materialu v alveolech vede k respiracnimu selhani různe tiže. V některých připadech neni možne provest celoplicni lavaž vyžadujici jednostrannou plicni ventilaci bez rizika zavažne periproceduralni hypoxie. V těchto vzacných připadech lze výkon provest za podpory mimotělni membranove oxygenace. Předkladana kazuistika popisuje připad 41leteho pacienta uspěsně leceneho opakovanou oboustrannou celoplicni lavaži provedenou za podpory veno‑venozni mimotělni membranove oxygenace. Mimotělni membranova oxygenace je použivana k provedeni celoplicni lavaže u pacientů s rizikem život ohrožujici hypoxie. Zvysujici se dostupnost a bezpecnost metod mimotělni podpory životnich funkci umožňuje rozsiřit indikaci jejich použiti o připady, kdy by provedeni plicni lavaže za použiti jednostranne plicni ventilace bylo sice možne, nicmeně zatižene významným rizikem komplikaci v důsledku zavažne hypoxie. Tato praxe zvysuje nejen bezpecnost, ale i efektivitu procedury, neboť umožnuje provest v jedne době oboustrannou lavaž.

Sedace je důležitou soucasti pece o ventilovane pacienty, jejimž cilem je zlepsit jejich komfort. V tomto přehledovem clanku je diskutovana adekvatni analgezie, klinicke hodnoceni hloubky sedace, srovnani lehke a hluboke sedace vcetně vlivu na klinicky relevantni výsledky a srovnani nejběžnějsich sedativ.

Diabetic foot ulcer (DFU) is a serious complication of diabetes and hyperbaric oxygen therapy (HBOT) is also considered in comprehensive treatment. The evidence supporting the use of HBOT in DFU treatment is controversial. The aim of this work was to introduce a DFU model in ZDF rat by creating a wound on the back of an animal and to investigate the effect of HBOT on the defect by macroscopic evaluation, quantitative histological evaluation of collagen (types I and III), evaluation of angiogenesis and determination of interleukin 6 (IL6) levels in the plasma. The study included 10 rats in the control group (CONT) and 10 in the HBOT group, who underwent HBOT in standard clinical regimen. Histological evaluation was performed on the 18th day after induction of defect. The results show that HBOT did not affect the macroscopic size of the defect nor IL6 plasma levels. A volume fraction of type I collagen was slightly increased by HBOT without reaching statistical significance (1.35+/-0.49 and 1.94+/-0.67 %, CONT and HBOT, respectively). In contrast, the collagen type III volume fraction was ~120 % higher in HBOT wounds (1.41+/-0.81 %) than in CONT ones (0.63+/-0.37 %; p=0.046). In addition, the ratio of the volume fraction of both collagens in the wound ((I+III)w) to the volume fraction of both collagens in the adjacent healthy skin ((I+III)h) was ~65 % higher in rats subjected to HBOT (8.9+/-3.07 vs. 5.38+/-1.86 %, HBOT and CONT, respectively; p=0.028). Vessels density (number per 1 mm2) was found to be higher in CONT vs. HBOT (206.5+/-41.8 and 124+/-28.2, respectively, p0.001). Our study suggests that HBOT promotes collagen III formation and decreases the number of newly formed vessels at the early phases of healing.

To point out possible infection with SARS-CoV-2 in symptomatic patients despite repeated negative nasopharyngeal swab tests for SARS-CoV-2.A retrospective observational study carried out at the Na Bulovce Hospital from the beginning of the pandemic until November 2020 included patients (1) who had symptoms compatible with COVID-19; (2) whose nasopharyngeal swab PCR tests in the presence of acute respiratory infection symptoms yielded two consecutive negative results; (3) in whom SARS-CoV-2 infection was subsequently confirmed by serology. Basic demographic and epidemiological data, symptoms, laboratory test results, X-ray findings and timing of virological tests were analysed for these patients.Seventeen patients met the inclusion criteria, 14 men and three women, aged 19-84 years with a median of 59 years, of whom 14 were hospitalized and three were treated as outpatients. Only seven patients were aware of the previous contact with an infected person. The main symptoms were fever, cough, headache, weakness, fatigue and shortness of breath. Pneumonia was found in 12 patients, four of whom developed respiratory insufficiency requiring ventilatory support. Most patients showed a uniform combination of haematological, biochemical and radio-logical findings: absence of eosinophils and increased polymorphonuclear/lymphocyte ratio; elevation of serum lactate dehydrogenase; elevation of CRP without rise of procalcitonin; typical chest CT or X-ray findings. All patients recovered. Coronavirus antigen test was performed in six patients, with all of them testing negative. SARS-CoV-2 infection was confirmed serologically by the detection of specific IgG and IgA in all 17 patients and also IgM in six patients, not before day 8 of the onset of symptoms.Our study showed that some patients with acute COVID-19 may test repeatedly negative by nasopharyngeal swab PCR. These cases should be interpreted as a low viral load in the upper respiratory tract rather than false negativity of PCR. Such alternative is not envisaged in the algorithms used. Considering our results, the following recommendation can be made: If, despite negative PCR tests, COVID-19 is still suspected based on clinical symptoms and epidemiological evidence, preliminary diagnosis can be made on the basis of comprehensive assessment of the laboratory test and X-ray findings. Final confirmation of the aetiology relies on serological tests performed two weeks after the onset of symptoms.

BackgroundBarotrauma to the middle-ear cavity and paranasal sinuses is a relatively common flight-related health problem. Occasionally, it may result in severe mechanical or infectious intracranial complications; these have been rarely reported to date.ObjectiveFour cases of acute bacterial meningitis following air travel are presented, and its pathogenesis is briefly described.ConclusionNeurological symptoms occurring after air flight should prompt proper investigation. Otitis media and sinusitis are common primary focuses of bacterial meningitis. Severe complications of air flight barotrauma may be underreported.

To summarize knowledge about the mana-gement in women with proven actinomyces in uterine cervix and inserted intrauterine device (IUD).An overall review.Actinomycosis is an uncommon but important subacute or chronic infection caused by anaerobic or microaerophilic bacteria, mainly within the Actinomyces genus. Actinomycosis can affect various organs and tissues in the human body, often manifesting draining sinuses, abscess formation and fibrosis. The pelvic form in women is the most common in the developed countries. Long-duration treatment with antibiotics can be completely effective even in cases of heavy disease. Although pelvic actinomycosis is predominantly associated with the longstanding use of intrauterine device, the risk of future symptomatic infection is extremly low even in women with a cervical Pap smear positive for actinomyces-like organisms (ALO). Therefore the identification of actinomycetes by cytology after cervical Pap smears is not diagnostic nor predictive of any disease because the actinomycetes normally reside in the female genital tract. In the absence of symptoms, patients with ALO on a Pap test do not need antimicrobial treatment or IUD removal. Nevertheless, women choosing an IUD for contraception should know that there is very low risk of developing the infection in later years after insertion.The sources of literature conclude that removal of the intrauterine device in a patients with a positive ALO in the uterine cervix is not necessary and antibiotics treatment is not required. However, IUD must be changed at least every five years in order to limit the risk of the development of pelvic actinomycosis.

Changes in cholesterol concentration in the plasma membrane of presynaptic nerve terminals nonspecifically modulate glutamate transport and homeostasis in the central nervous system. Reduction of the cholesterol content in isolated rat brain nerve terminals (synaptosomes) using cholesterol-depleting agents decreases the glutamate uptake and increases the extracellular level of glutamate in nerve terminals. Extraction of cholesterol from the plasma membrane and its further removal from the synaptosomes by external magnetic field can be achieved by means of magnetic nanoparticles with immobilized cholesterol-depleting agent such as O -methyl-β-cyclodextrin (MCD). A simple approach is developed for preparation of maghemite (γ-Fe 2 O 3 ) nanoparticles containing chemically bonded MCD. The method is based on preparation of a silanization agent containing MCD. It is synthesized by the reaction of triethoxy(3-isocyanatopropyl)silane with MCD. Base-catalyzed silanization of superparamagnetic γ-Fe 2 O 3 provides a relatively stable colloid product containing 48 μmol of MCD g −1 . MCD-modified γ-Fe 2 O 3 nanoparticles decrease the initial rate of the uptake and accumulation of l -[ 14 C]glutamate and increase the extracellular l -[ 14 C]glutamate level in the preparation of nerve terminals. The effect of MCD-immobilized nanoparticles is the same as that of MCD solution; moreover, magnetic manipulation of the nanoparticles enables removal of bonded cholesterol.

Monosized macroporous poly(glycidyl methacrylate) (PGMA) microspheres that were 9.3 μm in size were synthesized by multistep swelling polymerization using a modified Ugelstad technique. The PGMA microspheres and their hydrolyzed analogs derived from poly(2,3-dihydroxypropyl methacrylate) (PDHPMA) were coated by silanization with tetraethoxysilane (TEOS) and (3-aminopropyl)triethoxysilane (APTES), respectively. The particles were characterized by elemental and thermogravimetric (TGA) analysis, scanning and transmission electron microscopy (SEM and TEM) coupled with an energy dispersive X-ray analysis (EDAX) and FT-IR spectroscopy to determine the SiO2 content, morphology, particle size, polydispersity and structure. These types of particles are expected to have improved biocompatibility relative to their starting polymers.

gamma-Fe2O3 nanoparticles obtained by coprecipitation of Fe(II) and Fe(III) chlorides with a base and subsequent oxidation were coated with a shell of hydrophilic biocompatible poly(N,N-dimethylacrylamide) (PDMAAm). Various initiators were attached to the iron oxide surface to enable the use of the "grafting-from" approach for immobilization of PDMAAm. They included 2,2'-azobis(2-methylpropanimidamide) dihydrochloride (AMPA), 2,2'-azobis(N-hydroxy-2-methylpropanimidamide) dihydrochloride (ABHA) and 4-cyano-4-{[1-cyano-3-(N-hydroxycarbamoyl)-1-methylpropyl]azo}pentanoic acid (CCHPA). Engulfment of PDMAAm-coated y-Fe2O3 nanoparticles by murine J774.2 macrophages was investigated. Only some nanoparticles were engulfed by the macrophages. PDMAAm-AMPA-gamma-Fe2O3 and PDMAAm-ABHA-y-Fe2O3 nanoparticles were rapidly engulfed by the cells. In contrast, neat y-Fe2O3 and PDMAAm-CCHPA-gamma-Fe2O3 particles induced formation of transparent vacuoles indicating toxicity of the particles. Thus, PDMAAm-coated AMPA- and ABHA-gamma-Fe2O3 nanoparticles can be recommended as non-toxic labels for mammalian cells.

The advantages and disadvantages of various antibiotics used in the treatment of Clostridium difficile infection (CDI) are compared with respect to their pharmacokinetic and pharmacodynamic properties. Recommendations are made for their optimal use in clinical practice. Metronidazole is suitable for the treatment of mild forms of CDI which are essentially self-limiting. Vancomycin kills clostridia reliably but the treatment is encumbered with considerable risk of recurrence. This can be decreased by shortening the treatment to seven days and then switching to a (pulse, taper, chaser) regimen to prevent recurrence or by active restoration of the intestinal ecosystem (fecal transplant). Fidaxomicin works faster than vancomycin and is associated with a lower risk of recurrence. Thus, it can be profitably used in patients with impending ileus and also in those whose medical condition does not allow prolonged treatment. The duration of fidaxomicin treatment could be reduced to as few as five days. Rifaximin does not have a clear place in the treatment of CDI because no compelling data are available on its efficacy in this disease. The risk of resistance is also important. Tigecycline is a promising antibiotic for parenteral use. According to the available data, it should be more effective than intravenous metronidazole which has been considered the drug of choice.Clostridial colitis is associated with intestinal dysmicrobia which is the major cause of recurrence. Severe dysmicrobia cannot be treated by antibiotics but only by gut flora restoration; stool transplant from a healthy donor is the only proven therapy for this condition.

Gangrenous pyoderma is a rare complication of surgical treatment mimicking bacterial necrotizing fasciitis. The characteristic symptoms include a pre-existing immune disorder, negative results of the relevant microbiological examinations, no response to any antibiotic therapy, and deteriorating of the condition after radical debridement. Another typical feature is a discrepancy between an ominous appearance of the wound accompanied by leucocytosis and an elevated CRP level, and the patient s good general condition with low-grade fever and no signs of sepsis. The case of a 68-year-old man who underwent an elective open reconstruction of rotator cuff tears of the left shoulder is presented. The surgery was complicated with pyoderma gangrenosum that was first treated unsuccessfully by repeated revision surgery and broad-spectrum antibiotic therapy. The patient was ultimately cured with corticosteroids. The sequellae included limited motion of the shoulder joint and extensive destruction and scarring of the adjacent soft tissue.gangrenous pyoderma, necrotizing fasciitis, corticosteroids.

Poly(N,N-diethylacrylamide) (PDEAAm) hydrogel scaffolds were prepared by radical copolymerization of N,N-diethylacrylamide (DEAAm), N,N'-methylenebisacrylamide and methacrylic acid in the presence of (NH₄)₂SO₄ or NaCl. The hydrogels were characterized by low-vacuum scanning electron microscopy in the water-swollen state, water and cyclohexane regain, and by mercury porosimetry. The pentapeptide, YIGSR-NH₂, was immobilized on the hydrogel. Human embryonic stem cells (hESCs) were cultured with the hydrogels to test their biocompatibility. The results suggest that the PDEAAm hydrogel scaffolds are nontoxic and support hESC attachment and proliferation, and that interconnected pores of the scaffolds are important for hESC cultivation. Immobilization of YIGSR-NH₂ pentapeptide on the PDEAAm surface improved both adhesion and growth of hESCs compared with the unmodified hydrogel. The YIGSR-NH₂-modified PDEAAm hydrogels may be a useful tool for tissue-engineering purposes.

Monodisperse magnetic poly(glycidyl methacrylate) microspheres were prepared by dispersion polymerization of glycidyl methacrylate in cyclohexane in the presence of La 0.75 Sr 0.25 MnO 3 nanoparticles, surface of which was modified with penta(propylene glycol) methacrylate phosphate (PPGMAP). However, only agglomerates were formed by the dispersion polymerization in toluene. Sterical stabilizer was poly(styrene- block -hydrogenated butadiene- block -styrene) and initiators investigated were 2,2′-azobisisobutyronitrile (AIBN) and 4,4′-azobis(4-cyanovaleric acid) (ACVA). Effects of initiators and other reaction conditions on properties of the composite microspheres were evaluated. The phase composition of the magnetic polymer composite microspheres and the size of magnetic cores were determined by X-ray powder diffraction. The characterization was completed by magnetization measurements, atomic absorption spectroscopy, TEM, SEM and ATR FTIR spectroscopy.

Maghemite (γ-Fe2O3) colloid has been synthesized by coprecipitation of ferrous and ferric salts in alkaline medium and oxidation. The obtained nanoparticles were complexed with a phosphate macromonomer—penta(propylene glycol) methacrylate phosphate (PPGMAP). Complexes with the weight ratio PPGMAP/γ-Fe2O3 0.01–10 were investigated using a range of characterization methods. The amount of PPGMAP attached to the particles was about 22 wt %. The size and size distribution of the γ-Fe2O3 core particles in the dry state was measured by TEM. To complete the TEM images, the hydrodynamic size of the nanoparticles including polymer shell and the maghemite core was determined by DLS measurements in toluene. Magnetic poly(glycidyl methacrylate) (PGMA) nanospheres were obtained by Kraton G 1650-stabilized and 2,2′-azobisisobutyronitrile-initiated polymerization of glycidyl methacrylate (GMA) in toluene or toluene/cyclohexane mixture in the presence of PPGMAP-coated γ-Fe2O3 colloid. The effect of Kraton G 1650 concentration on the morphology, PGMA nanosphere size and polydispersity was investigated. The particles were characterized also by both thermogravimetric analysis and magnetic measurements. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4982–4994, 2009

Two samples of chemically modified seaweed Ascophyllum nodosum (NS-1 and DS-1) were used for selective removal of metal (W, Mo, V, Ge, and Sb) oxoanions. All experiments were carried out by dynamic column sorption. The effects of pH, the concentration of the accompanying anions in the feed solution, and the effect of the flow rate were studied. Tungstate, molybdate, and vanadate were adsorbed extensively. Sorption of Sb(III) anion was notable but the sorption capacity was very low and the desorption was difficult. Sorption of Ge(IV) oxoanion was negligible. Stability of the NS-1 and DS-1 sorbents was limited by, 20 and 25 sorption cycles, respectively.

The interactions of two model phosphoproteins (porcine pepsin and ovalbumin) with two different immobilized metal affinity chromatography (IMAC) sorbents containing immobilized Fe3+, Ga3+, and UO22+ ions have been investigated under various conditions. Both proteins were adsorbed on immobilized uranyl ions under acidic conditions similar to those on immobilized Fe3+ and Ga3+ ions. The retained proteins could be released either by the presence of phosphate ions in the elution buffer (immobilized Ga3+ and Fe3+ ions) or by an increased pH (all tested immobilized ions). The IMAC sorbents employed could be used under the conditions of high-performance chromatography and are suitable for the separation and analysis of intact phosphoproteins.

The interactions of pepsin with immobilized trivalent metal ions and the participation of the enzyme phosphate group in this process were investigated using high performance immobilized metal affinity chromatography. Two different sorbents were used: the newly prepared one, consisting of Ga 3+ chelate of (6-amino-1-hydroxy-hexane-1,1-diyl) bis(phosphonic acid) covalently bound to a methacrylate support (BP-Ga 3+ ), and the commercial one, containing immobilized Fe 3+ ions (POROS MC20-Fe 3+ ). The comparison of the behavior of porcine pepsin A and its partially dephosphorylated form on both sorbents showed that both forms of pepsin were adsorbed under the same conditions. To eliminate the participation of free carboxyl groups in pepsin adsorption, both enzyme forms were modified by amidation or esterification. Native enzyme and its partially dephosphorylated form both with modified carboxyl groups differed in their interaction with immobilized Ga 3+ and Fe 3+ . Phosphorylated pepsin molecules with esterified carboxyl groups were adsorbed on both sorbents while nonphosphorylated ones with esterified carboxyl groups were not adsorbed.

A short liposome exposure to ultrasonic waves with the intensity of I = 2 W/cm2 at frequency f = 1 MHz was found to be a sufficient tool for liposome opening. In addition, shock-wave proved to be sufficient also for liposome content release. Both methods are useful tools to be used as control mechanisms for drug delivery systems based on liposomes. However, due to better focusing and low non-thermal side effects, shock-waves probably have a markedly higher potential for successful use.

Two methods of modification of poly[(glycidyl methacrylate)- co -(ethylene dimethacrylate)] microspheres with urea were examined in this electrorheological (ER) study. First, the urea functional groups were introduced by chemical modification of the starting copolymer. A significant increase in storage modulus of the silicone oil suspension was observed compared with the loss modulus when an electric field is applied. On the other hand, the ER effect in suspension of particles coated with physically bonded urea was only slightly higher than that of untreated material. This is explained by poor coating of the hydrophobic microparticle surface with hydrophilic urea. According to dielectric measurements, the interfacial polarization was found to be responsible for the formation of chain structure of modified microspheres in the electric field resulting in the ER effect.

Macroporous polymethacrylates containing imidazole groups as well as hydrophobic side chains adsorb methemoglobin (metHb). The protein-matrix interaction was investigated by means of an electron paramagnetic resonance (EPR) spectroscopy. The adsorption of metHb to the imidazole containing matrices occurs by complex formation with the iron of the prosthetic group. In case of steric hindrance or long spacers, this complex formation is not primarily responsible for the adsorption. The binding of metHb to hydrophobic side chains clearly demonstrates the presence of a metHb-H2O-metHb-OH mixture. Moreover, the protein-matrix interaction induces conformational changes in the protein component. In this case, additional signals in the EPR spectra indicate the formation of a cytochrome P450-like structure.

Polymers of ethylene methacrylate, toluene-, and benzenesulfonate are shown to be strongalkylating agents. Their polymer-analogous reaction with most nucleophiles proceeds smoothly under conditions comparable to those of low molecular analogs. The nucleophiles used successfully were of the nitrogen type: amines, pyridine, phthalimidate, azide; or oxygen: alkoxide, phenolate, carboxylate; sulfur: thioacetate, thiocyanate, thiourea; and other types: iodide. Further reaction of some of these derivatives, e.g., hydrolysis to thiol or amine, proceeds as expected.

A polyconjugated polymer obtained by polymerization of tetrolonitrile with anionic catalysts is described. The monomer was synthetized from methyltetrolate via tetrol-amide with better yields and purity than obtained with other methods. Polymerization was initiated by butyllithium and lithium naphthalene in tetrahydrofuran at 0° and −80°C., yielding a dark-brown product, soluble in polar solvents. Molecular weight, electrical conductivity in solid state and in solution, as well as infrared and ESR spectra were determined. The properties of the substance are discussed in connection with the proposed polyenic structure.

Carboxyl group-containing magnetic nonporous poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) (P(HEMA-co-GMA)) microspheres and cobalt ferrite nanoparticles modified with alginic acid (natural carboxylic polysaccharide) were used for isolation of microbial DNA of lactic acid bacteria (LAB) from dairy products, lyophilised cell cultures, and bacterial colonies grown on hard media, and Trichophyton fungi DNA from lyophilised cells. DNA from the samples with lysed cells was reversibly adsorbed to the particles in the presence of high poly(ethylene glycol) (PEG 6000) and sodium chloride concentrations. The optimal final PEG and NaCl concentrations were 9.1 wt.% and 2.0 M, respectively. The adsorbed DNA was released from the particles in low ionic strength TE buffer. The quality of isolated DNA was checked by PCR amplification. Moreover, PCR amplicons were isolated on cobalt ferrite nanoparticles modified with alginic acid and checked by restriction analysis.

Heterogeneous catalysts based on magnetic mixed iron oxides (MO·Fe 2 O 3 ; M: Fe, Co, Cu, Mn) were used for the decolorization of several synthetic dyes (Bromophenol Blue, Chicago Sky Blue, Cu Phthalocyanine, Eosin Yellowish, Evans Blue, Naphthol Blue Black, Phenol Red, Poly B-411, and Reactive Orange 16). All the catalysts decomposed H 2 O 2 yielding highly reactive hydroxyl radicals, and were able to decolorize the synthetic dyes. The most effective catalyst FeO·Fe 2 O 3 (25 mg mL −1 with 100 mmol L −1 H 2 O 2 ) produced more than 90% decolorization of 50 mg L −1 Bromophenol Blue, Chicago Sky Blue, Evans Blue and Naphthol Blue Black within 24 h. The fastest decomposition proceeded during the first hour of the reaction. In addition to dye decolorization, all the catalysts also caused a significant decrease of chemical oxygen demand (COD). Individual catalysts were active in the pH range 2–10 depending on their structure and were able to perform sequential catalytic cycles with low metal leaching.

The preparation of an easily replaceable protease microreactor for micro-chip application is described. Magnetic particles coated with poly(N-isopropylacrylamide), polystyrene, poly(2-hydroxyethyl methacrylate-co-ethylene dimethacrylate), poly(glycidyl methacrylate), [(2-amino-ethyl)hydroxymethylen]biphosphonic acid, or alginic acid with immobilized trypsin were utilized for heterogeneous digestion. The properties were optimized, with the constraint of allowing immobilization in a microchannel by a magnetic field gradient. To obtain the highest digestion efficiency, sub-micrometer spheres were organized by an inhomogeneous external magnetic field perpendicularly to the direction of the channel. Kinetic parameters of the enzyme reactor immobilized in micro-chip capillary (micro-chip immobilized magnetic enzyme reactor (IMER)) were determined. The capability of the proteolytic reactor was demonstrated by five model (glyco)proteins ranging in molecular mass from 4.3 to 150 kDa. Digestion efficiency of proteins in various conformations was investigated using SDS-PAGE, HPCE, RP-HPLC, and MS. The compatibility of the micro-chip IMER system with total and limited proteolysis of high-molecular-weight (glyco)proteins was confirmed. It opens the route to automated, high-throughput proteomic micro-chip devices.

Stationary phase containing quinolin-8-ol immobilized on macroporous methacrylate support for the affinity chromatography of porcine pepsin A is described. Optimized chromatographic conditions for separation of porcine pepsin A on this stationary phase were found investigating the influence of pH, concentration, ionic strength and chemical composition of the used mobile phases. The stationary phase shows a good reproducibility of chromatographic analyses (relative standard deviation, +/-2%), a high recovery (ca. 93%) and a satisfactory capacity (13 mg pepsin A/1 mL stationary phase) for porcine pepsin A. The obtained findings confirm the applicability of affinity chromatography on the stationary phase with immobilized quinolin-8-ol to the isolation and determination of porcine pepsin A.

Chelating sorbents with 8-hydroxyquinoline (IVa), 8-hydroxyquinoline-5-sulfonic acid (IVb), and tris(2-aminoethyl)amine (VI) ligands immobilized on macroporous methacrylate matrix were prepared and saturated with Co(II), Cu(II), and Fe(II). All these chelates catalyze cleavage of H2O2 yielding highly reactive hydroxyl radicals. All were able to degrade by this mechanism polycyclic aromatic hydrocarbons (anthracene, benzo[a]pyrene and benzo[k]fluoranthene). The most effective catalysts IVa-Fe, IVb-Fe, and VI-Cu (25 mg with 100 mmol H2O2) performed complete decomposition of 33 mg anthracene and benzo[a]pyrene during one 7-day catalytic cycle at 25 8C. The fastest decomposition proceeded during the 1st day of incubation; 75% of anthracene and 74% of benzo[a]pyrene were decomposed by IVb-Co within the first 24 h. More than 25% decomposition within the 1st day was also achieved with IVb-Fe, VI-Cu, IVa-Cu, and VI-Co for anthracene and more than 30% benzo[a]pyrene was decomposed by IVb-Fe, VI-Cu, IVa-Cu, and IVb-Cu during the same period. 1,4Anthracenedione was the main product of anthracene oxidation by all catalysts. The catalysts were stable at pH 2–11 depending on their structure and able to perform sequential catalytic cycles without regeneration. # 2005 Elsevier B.V. All rights reserved.

The influence of cobalt ferrite particles, with non-modified or modified surface, on the course of polymerase chain reaction (PCR) was investigated. DNA isolated from bacterial cells of Bifidobacterium bifidum was used in PCR evaluation of magnetic microspheres. The presence of cobalt ferrite particles inhibits PCR amplification. The effect is not dependent on the functional groups of the modifying reagents used (none, amino, carboxyl). Amplification was improved after the magnetic separation of magnetic particles. Proposed indirect method enabled verification of the suitability of designed particles for their application in PCR assays. Magnetic particles coated with alginic acid under high PEG and sodium chloride concentration were used for the isolation of PCR-ready bacterial DNA from various dairy products. DNA was isolated from crude bacterial cell lysates without phenol extraction of samples. Bifidobacterium and Lactobacillus DNAs were identified in dairy products using PCR.

The newly developed magnetic micro- and nanoparticles with defined hydrophobicity and porosity were used for the preparation of magnetic enzyme reactors. Magnetic particles with immobilized proteolytic enzymes trypsin, chymotrypsin and papain and with enzyme neuraminidase were used to study the structure of heterogeneous glycoproteins. Factors such as the type of carrier, immobilization procedure, operational and storage stability, and experimental conditions were optimized.

Magnetic poly(2-hydroxyethyl methacrylate)- and poly(glycidyl methacrylate)-based microparticles were prepared by dispersion polymerization in the presence of iron oxide nanoparticles, both commercial and laboratory-made. The polymerization was highly sensitive to even subtle changes in the various reaction parameters involved in the process. The size of the final microparticles was determined by the composition of the dispersion medium (e.g. water/ethanol ratio, monomer concentration at the moment of phase separation, stabilizer concentration, initiator type and concentration, polymerization temperature). Several DNA applications of developed microparticles were described, among others RNA and DNA degradation and Salmonella cell magnetic separation by RNase A and DNase I and anti-Salmonella or proteinase K immobilized on developed magnetic carriers. The sensitivity of polymerase chain reaction (PCR) in cell detection was negatively affected by some magnetic carriers and compounds used in their preparation. Carboxyl group-containing magnetic microparticles were prepared for isolation of genomic DNA from cell lysate in the presence of poly(ethylene glycol) and sodium chloride.

Adsorption separation techniques as an alternative to laborious traditional methods (e.g., based on phenol extraction procedure) have been applied for DNA purification. In this work we used two types of particles: silica and cobalt ferrite (unmodified or modified with a reagent containing weakly basic aminoethyl groups, aminophenyl groups, or alginic acid). DNA from chicken erythrocytes and DNA isolated from bacteria Lactococcus lactis were used for testing of adsorption/desorption properties of particles. The cobalt ferrite particles modified with different reagents were used for isolation of PCR-ready bacterial DNA from different dairy products.

Sorbents containing quinolin-8-ol groups were synthesized by the chemical transformation of macroporous poly(glycidyl methacrylate-co-ethylene dimethacrylate) copolymer using the Mannich reaction. These sorbents were transformed into Ag(I), Cu(II), and Fe(III) forms, respectively. The interactions with substituted phenols were studied by inverse liquid chromatography. Phenols are retained more strongly on the metal complexes of quinolin-8-ol sorbent than on the uncomplexed quinolin-8-ol sorbent. Strong interactions of benzene-1,2-diols, benzene-1,2,3-triols and 4-nitrophenol with the adsorbent in the Cu(II) and Fe(III) form are explained by the chelate effect or by ionic bond formation. The intensity of the interactions decreases when the eluents are exchanged from water or water/methanol mixtures to the less polar methanol.

The use of free lanthanide ions and their complexes for plasmid DNA pBR322 and chromosomal DNA cleavage was studied. Plasmid pBR322 DNA was treated by lanthanide chlorides (Eu(3+), La(3+), Nd(3+), Pr(3+), Gd(3+)) in HEPES buffer (pH 7.0, 7.5 and 8.0) at 24, 37, 50, 63, and 76 degrees C. The formation of linear and nicked plasmid forms was investigated depending on the reaction conditions. Heterogeneous lanthanide complexes of ethylenediamine tetraacetic acid (EDTA) immobilized on insoluble methacrylate support and iminodiacetic acid (IDA) immobilized on styrene support were used as catalysts plasmid for DNA pBR322 cleavage, too. The temperature of reaction mixture had substantial influence on cleavage rate. The precipitation of DNA occurred during the measurement of interactions between chromosomal DNA and La(3+) ions.