The effects of ionic liquids on model phospholipid membranes were studied by small-angle X-ray scattering, dynamic light scattering (DLS) and zeta potential measurements. Multilamellar 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine liposomes and large unilamellar vesicles composed of l-α-phosphatidylcholine (eggPC) and l-α-phosphatidylglycerol (eggPG) (80:20mol%) or eggPC, eggPG, and cholesterol (60:20:20mol%) were used as biomimicking membrane models. The effects of the phosphonium-based ionic liquids: tributylmethylphosphonium acetate, trioctylmethylphosphonium acetate, tributyl(tetradecyl)-phosphonium acetate, and tributyl(tetradecyl)-phosphonium chloride, were compared to those of 1-ethyl-3-methyl-imidazolium acetate. With multilamellar vesicles, the ionic liquids that did not disrupt liposomes decreased the lamellar spacing as a function of concentration. The magnitude of the effect depended on concentration for all studied ionic liquids. Using large unilamellar vesicles, first a slight decrease in the vesicle size, then aggregation of vesicles was observed by DLS for increasing ionic liquid concentrations. At concentrations just below those that caused aggregation of liposomes, large unilamellar vesicles were coated by ionic liquid cations, evidenced by a change in their zeta potential. The ability of phosphonium-based ionic liquids to affect liposomes is related to the length of the hydrocarbon chains in the cation. Generally, the ability of ionic liquids to disrupt liposomes goes hand in hand with inducing disorder in the phospholipid membrane. However, trioctylmethylphosphonium acetate selectively extracted and induced a well-ordered lamellar structure in phospholipids from disrupted cholesterol-containing large unilamellar vesicles. This kind of effect was not seen with any other combination of ionic liquids and liposomes.

• MeSH
• Cholesterol chemistry   MeSH
• X-Ray Diffraction MeSH
• Dynamic Light Scattering MeSH
• Phospholipids chemistry   MeSH
• Ionic Liquids chemistry   MeSH
• Liposomes chemistry   MeSH
• Scattering, Small Angle MeSH
• Organophosphorus Compounds chemistry   MeSH
• Unilamellar Liposomes chemistry   MeSH
• Publication type
• Journal Article MeSH

Polar analytes that possess protic functional groups have often been treated with alkyl chloroformates to decrease their polarity and increase their volatility prior to gas chromatography-mass spectrometry analysis. This derivatization reaction has two distinct advantages. It proceeds smoothly in aqueous media, and the desired reaction products are efficiently separated from interfering ionic components by their extraction into a water-immiscible organic phase. In the present work, the derivatization-liquid liquid sample preparation was examined in detail for analysis of a potential urinary dipeptide biomarker L-prolyl-4-L-hydroxyproline (PHP) by downstream liquid chromatography coupled to electrospray mass spectrometry. PHP was treated with a series of alkyl and fluoroalkyl chloroformates in aqueous media, and the detected reaction products were investigated. Smooth conversion of PHP into the N-isobutyloxycarbonyl isobutyl ester was accomplished by the coupled action of isobutanol, isobutyl chloroformate and the pyridine catalyst. This derivative afforded a highest detector response from all the derivatized forms examined, including the nonderivatized PHP. A simple isocratic elution on a common RP-C18 HPLC column coupled with tandem mass spectrometry, and use of the synthesized heptadeuterated analog (D7-PHP) as an internal standard, enabled validation of the method and determination of PHP in human urine in less than 5 min. The in situ derivatization-liquid liquid extraction has thus been demonstrated to be a useful sample preparation strategy for the analysis of polar metabolites by liquid chromatography-tandem mass spectrometry in the complex urine matrix.

• MeSH
• Biomarkers chemistry   urine   MeSH
• Dipeptides urine   MeSH
• Liquid-Liquid Extraction methods   MeSH
• Humans MeSH
• Linear Models MeSH
• Reproducibility of Results MeSH
• Sensitivity and Specificity MeSH
• Drug Stability MeSH
• Tandem Mass Spectrometry methods   MeSH
• Chromatography, High Pressure Liquid methods   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

• MeSH
• Chemistry, Physical MeSH
• Publication type
• Monograph MeSH

• Conspectus
• Fyzikální chemie
• NML Fields
• chemie, klinická chemie

The role of microorganisms in litter degradation in arid and semi-arid zones, where soil and water salinization is one of the main factors limiting carbon turnover and decay, remains obscure. Heterostachys ritteriana (Amaranthaceae), a halophyte shrub growing in arid environments such as "Salinas Grandes" (Córdoba, Argentina), appears to be the main source of organic matter in the area. Little is known regarding the microorganisms associated with H. ritteriana, although they are a potential source of enzymes such as cellulolytic ones, which might be important in biotechnological fields such as bioethanol production using ionic liquids. In the present study, by studying the microbiota growing on H. ritteriana leaf litter in "Salinas Grandes," we isolated the cellulolytic fungus Fusarium equiseti LPSC 1166, which grew and degraded leaf litter under salt stress. The growth of this fungus was a function of the C substrate and the presence of NaCl. Although in vitro the fungus used both soluble and polymeric compounds from H. ritteriana litter and synthesized extracellular β-1,4 endoglucanases, its activity was reduced by 10% NaCl. Based on these results, F. equiseti LPSC 1166 can be described as a halotolerant cellulolytic fungus most probably playing a key role in the decay of H. ritteriana leaf litter in "Salinas Grandes."

• MeSH
• Biodegradation, Environmental MeSH
• Cellulose metabolism   MeSH
• Chenopodiaceae microbiology   MeSH
• Sodium Chloride metabolism   MeSH
• Fungal Proteins genetics   metabolism   MeSH
• Fusarium enzymology   genetics   metabolism   MeSH
• Glycoside Hydrolases genetics   metabolism   MeSH
• Plant Leaves microbiology   MeSH
• Publication type
• Journal Article MeSH

OBJECTIVES: 2,3,7,8-tetrachloro-dibenzo-p-dioxin (TCDD) is a highly toxic persistent environmental contaminant, classified as a human carcinogen affecting any target organ. The mechanism of carcinogenesis by TCDD is unclear as TCDD shows a lack of direct genotoxicity. Experimental studies also support the role of oxidative stress in TCDD neurotoxicity and vascular dysfunction. The aim was to investigate markers of oxidative/nitrosative stress and inflammation using non-invasive methods in subjects who got ill due to severe occupational exposure to TCDD in the years 1965-1968. METHODS: In 11 TCDD-exposed patients, and 16 controls, the analysis of following oxidative products of lipids, proteins and nucleic acids in plasma, urine and exhaled breath condensate (EBC) was performed: 8-iso-prostaglandin F2α (8-isoprostane), 4-hydroxy-trans-2-nonenale (HNE), malondialdehyde (MDA), o-tyrosine (o-Tyr), 8-hydroxyguanosine (8-OHG), 8-hydroxy-2 ́-deoxy-guanosine (8-OHdG), 5-hydroxymethyluracil (5-OHMeU). In addition, nitric-oxide-tyrosine (NO-Tyr) and leukotriene (LT) B4, C4, D4, and E4 were detected by liquid chromatography-mass spectrometry/mass spectrometry (LC-ESI-MS/MS). TCDD was measured by HRGC/HRMS, body lipid content by densitometry. Single-photon emission spectrometry (SPECT) of the brain was performed and compared with the findings of the patients in 2008. RESULTS: Mean TCDD plasma level in 2010 was 175 ± 162 pg/g lipids (population level about 2 pg/g), total TCDD content in the body 5.16 ± 4.62 mg. Reduction of cerebral blood flow in SPECT progressed in 8 patients, finding was stable in 2 subjects, and improvement occurred in 1 patient. In the EBC, 10 from 12 markers (all except LT D4 and LT E4), were significantly increased in the patients (p<0.05). In the urine, 7 markers were significantly higher than in the controls (p<0.05): 8-isoprostane, MDA, HNE, LT C4, LT E4, o-Tyr and NO-Tyr. In plasma, only NO-Tyr and 8-OHG were elevated (p<0.05). CONCLUSION: NO-Tyr was increased in all matrices in dioxin-exposed patients. EBC is not limited to lung disorders as the markers of oxidative stress and inflammation were elevated in EBC of patients with normal lung functions. TCDD-induced oxidative stress and inflammation markers can be detected non-invasively in the EBC and urine in the follow-up of the highly-exposed patients. Their prognostic value, however, needs to be elucidated.

• MeSH
• Urinalysis methods   MeSH
• Blood Chemical Analysis methods   MeSH
• Biomarkers analysis   blood   urine   MeSH
• Chemical Industry MeSH
• Herbicides analysis   blood   MeSH
• Middle Aged MeSH
• Humans MeSH
• Osmolar Concentration MeSH
• Oxidative Stress physiology   MeSH
• Polychlorinated Dibenzodioxins analogs & derivatives   analysis   blood   MeSH
• Occupational Exposure analysis   MeSH
• Reactive Nitrogen Species analysis   blood   metabolism   urine   MeSH
• Reactive Oxygen Species analysis   blood   metabolism   urine   MeSH
• Aged MeSH
• Case-Control Studies MeSH
• Up-Regulation MeSH
• Check Tag
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Evaluation Study MeSH
• Research Support, Non-U.S. Gov't MeSH

• Keywords
• Lékařské obory,
• MeSH
• Biophysics MeSH

• NML Fields
• fyzika, biofyzika

1. Existující teorie akupunktury jsou založeny na jednotlivých experimentálních údajích a nepostihují podstatu problému: funkci akupunkturních bodů, podstatu meridiánů, biologickou účelnost fyziologických reakcí vyvolaných stimulací akupunkturních bodů. 2. Navrhujeme hodnocení funkční úlohy akupunktury v termínech navržené hypotézy „ekoceptivního systému“ řídícího elektromagnetickou homeostázu organismu. Úlohu elektromagnetických receptorů plní funkčně sjednocené akupunkturní body. 3. Aferentní část ekoceptivního systému tvoří jednotná soustava pojivé tkáně – matrice, spojující vnější prostředí přes akupunkturní body s mezibuněčným prostorem a také s intracelulárními strukturami. Tyto proteinové struktury vykazují vlastnosti kapalných krystalů, jsou schopny pohlcovat elektromagnetické pole infračerveného a mikrovlnného rozsahu, vést energii elektromagnetického pole v jednom směru a vyvolávat piezoelektrický efekt. Byly získány experimentální důkazy toho, že vlákna pojivové tkáně vykazují iontovou a elektronovou vodivost. V řadě tkání jsou buňky, které jsou navzájem spojeny přímými transmembránovými kanály – „konexonovými spoji“. Konexonovými spoji mohou být vedeny ionty a elektrony. Matrice zajišťuje „informační“ řízení fyziologických procesů a účastní se elektromagnetické recepce. 4. Dosažení rovnováhy jednotného fyzikálního pole organismu a předávání informace o porušeních tohoto pole se uskutečňuje vrstvami intersticiální pojivové tkáně – meridiány spojenými s cytoskeletem a s jádrem každé buňky do jednotného morfologicko-funkčního systému. 5. Klíčovými složkami funkčního systému regulace elektromagnetické rovnováhy organismu jsou: elektromagnetické receptory (akupunkturní body), molekulární fotoreceptory, vodivé cesty (kolagenové a fotospecifické bílkovinové struktury) a akceptory výsledku působení (struktury vykazující energetickou nerovnováhu). Kromě přímé kontroly nervovým a endokrinním systémem závisí činnost „ekoceptivního“ systému na parametrech vnější elektromagnetické energie a energetickém zabezpečení struktur organismu.

1. Existing theories of acupuncture are based on particular experimental data and do not completely cover the principle of the problem: function of acupuncture points, principle of meridians, and biological purpose of physiological reactions induced by the stimulation of acupuncture points. 2. We propose an assessment of the functional role of acupuncture in terms of the proposed hypothesis of the “ecoceptive system” controlling the electromagnetic homeostasis of the organism. The functionally unified acupuncture points fulfil the task of electromagnetic receptors. 3. The afferent part of the ecoceptive system is formed by a uniform system of the connective tissue – matrix, connecting the external environment through acupuncture points with intercellular space and also with intracellular structures. These protein structures exert characteristics of liquid crystals, which are able to absorb the electromagnetic field of infrared and microwave ranges, to conduct the electromagnetic field energy in one direction and to induce the piezoelectric effect. Experimental demonstrations were acquired indicating that fibres of the connective tissue exert ionic and electron conductivity. In a number of tissues, there are cells, which are interconnected by direct transmembrane channels – “conexon synapses”. Ions and electrons can be connected through the conexon synapses. The matrix provides “informational” control of physiologic processes and participates in the electromagnetic reception. 4. The achievement of the equilibrium of a uniform physical field in the organism and transfer of information about disturbances of this field is implemented through the mediation of interstitial connective tissue layers – meridians connected with the cytoskeleton and nucleus of each cell into a uniform morphologically-functional system. 5. Key components of the functional system of the electromagnetic regulation of the organism equilibrium are as follows: electromagnetic receptors (acupuncture points), molecular photoreceptors, conductive tracks (collagen and photospecific protein structures) and acceptors of action results (structures exerting energy equilibrium). In addition to the direct control over the nervous and endocrine system, the activity of the ecoceptive system depends on parameters of the external electromagnetic energy and on providing the organism structures with energy.

• MeSH
• Acupuncture MeSH
• Acupuncture Points MeSH
• Meridians MeSH
• Qi MeSH
• Electromagnetic Fields MeSH
• Homeostasis MeSH
• Humans MeSH
• Check Tag
• Humans MeSH

• MeSH
• Biochemistry MeSH
• Chemistry MeSH
• Chemistry, Organic MeSH

• Conspectus
• Chemie. Mineralogické vědy
• NML Fields
• chemie, klinická chemie
• NML Publication type
• kolektivní monografie

• MeSH
• Biophysics MeSH

• Conspectus
• Lékařské vědy. Lékařství
• Učební osnovy. Vyučovací předměty. Učebnice
• NML Fields
• fyzika, biofyzika
• NML Publication type
• učebnice vysokých škol

• Conspectus
• Biotechnologie. Genetické inženýrství
• NML Fields
• biomedicínské inženýrství