Effect of 50 Hz magnetic field exposure on the adherent cell contacts of primary mouse Leydig cells in culture

Mouse primary testicular intersitital (Leydig) cells obtained from 30-35 g NMRI mice were exposed in a CO2 incubator to a sinusoidal 50 Hz/100 µT magnetic field for 48 h. Non-exposed, human choriogonin stimulated (0.1 mIU/ml hCG) cells were also cultured as positive controls. Cells were grown as monolayer on cover slips posited on the bottom of the plastic 24-well culture plates. Following the incubation the cells were fixed and permeabilized with -20ºC methanol for 2 hours. For immunocytochemical detection of cadherins, ß-catenin and tubulin, cells were incubated over 60 minutes at room temperature with (1:300 diluted) pan-cadherin, anti-ß-catenin or antitubulin. Anti-mouse FITC developed in rabbit was used as secondary antibody. Evaluating the samples by fluorescent microscopy, we found that the applied magnetic field exposure increased the amounts of cadherins and ß-catenin along the surface of the cell-to-cell contacts. The amount of microtubuli was also elevated and typical shape of cells was changed. The effects of magnetic field exposure were similar to those caused by hCG in the positive controls. Further investigations are required to clarify the subcellular action of applied magnetic field in Leydig cells

Účinok 4-octylphenolu na bazálnu a stimulovanú produkciu testosterónu myších Leydigových buniek

Octylphenol is biodegradation product of alkylphenolethoxylates frequently used in detergents, paints and other industrial applications. This compound is classified as an endocrine disruptor. Recent studies have hypothesized that occupational exposure to octylphenol poses adverse effects on reproductive system of humans and wildlife species. Enzymes involved in the steroid biosynthesis pathway are really sensitive targets for the action of various endocrine-disrupting chemicals. Aim of in vitro study was determined the effect of 4-octylphenol on basal and human chorionic gonadotropin stimulated testosterone formation of ICR mice Leydig cells. On the other hand, was classified potential impact of mentioned endocrine disruptor on Leydig cell viability after 44 h of cultivation. Cell suspension was cultured with addition of 0.04; 0.2; 1.0; 2.5 and 5.0 μg*mL-1 of 4-octylphenol and compared to the control. Hormone quantification from the medium was performed by enzyme-linked immunosorbent assay. Viability of cell suspension was determined by the metabolic activity assay. Unstimulated testosterone production significantly (P˂0.001) increased with 2.5 and 5.0 μg*mL-1 4-octylphenol. Cell viability was also significantly (P˂0.001; P˂0.05) stimulated by 4-octylphenol. Although human chorionic gonadotropin stimulated testosterone secretion was significantly (P˂0.05) affected by the lowest concentration (0.04 μg*mL-1) in the cell viability was recorded significantly (P˂0.001; P˂0.05) higher mitochondrial activity (1.0; 2.5 and 5.0 μg*mL-1). Considerably more detailed and systematic research in this area is required for a better understanding of potential risk to humans or animals.Octylphenol je biodegradačný produkt alkylphenol-ethoxylátov, ktorý je široko využívaný v detergentoch, farbivách a ďalších industriálnych produktoch. Zároveň je klasifikovaný ako endokrinný disruptor. Nedávne štúdie poukazujú na fakt, že pôsobenie octylphenolu vyvoláva negatívne účinky v reprodukčnom systéme ľudí a zvierat. Enzýmy, ktoré sú zapojené do procesu biosyntézy steroidov sú veľmi citlivé na pôsobenie endokrinných disruptorov. Táto in vitro štúdia bola zameraná na sledovanie účinku 4-octylphenolu na bazálnu a hCG stimulovanú produkciu testosterónu u ICR myších Leydigových buniek. Rovnako bol klasifikovaný účinok spomínaného endokrinného disruptora na viabilitu týchto buniek po 44 hodinovej kultivácií. Bunková suspenzia bola kultivovaná s prídavkom 0,04; 0,2; 1,0; 2,5 a 5.0 μg*mL-1 4-octylphenolu a porovnávaná s kontrolou. Kvantifikácia množstva testosterónu bola vykonávaná priamo z média pomocou imunoanalýzy. Pre stanovenie viability Leydigových buniek bol využitý MTT test. Bazálna produkcia testosterónu bola signifitantne (P˂0.001) zvýšená v koncentráciách 2,5 a 5,0 μg*mL-1 4-octylphenolu. Pri sledovaní životaschopnosti bol zaznamenaný signifikantný (P˂0.001; P˂0.05) nárast v koncentráciách 1,0 ; 2,5 a 5,0 μg*mL-1 4-octylphenolu v porovnaní s kontrolou. Stimulovaná produkcia testosterónu pomocou hCG spolu s pôsobením 4-octylphenolu spôsobila siginifikantý nárast produkcie v najnižšej koncentrácií testovanej látky. V prípade bunkovej viability bola zaznamenaná signifikantne(P˂0.001; P˂0.05) vyššia mitochondriálna aktivita exponovaných buniek (1,0; 2.5 a 5.0 μg*mL-1). Ďalší systematický výskum v oblasti pôsobenia endokrinných disruptorov považujeme za veľmi potrebný pre lepšie pochopenie potenciálnych rizík pre ľudí a zvieratá

A dynamical survey of the trans-Neptunian region II.: On the nature of chaotic diffusion

On long enough timescales, chaotic diffusion has the potential to significantly alter the appearance of a dynamical system. The solar system is no exception: diffusive processes take part in the transportation of small bodies and provide dynamical pathways even for the distant trans-Neptunian objects to reach the inner solar system. In this Letter, we carry out a thorough investigation of the nature of chaotic diffusion. We analyze the temporal evolution of the mean squared displacement of ten thousand ensembles of test particles and quantify in each case the diffusion exponent (enabling the classification between normal, sub-, and super-diffusion), the generalized diffusion coefficient, and a characteristic diffusion timescale, too. This latter quantity is compared with an entropy-based timescale, and the two approaches are studied in light of direct computations as well. Our results are given in the context of two-dimensional maps, thereby facilitating the understanding of the relationship between the typical phase space structures and the properties of chaotic diffusion.Comment: 6 pages, 7 figures, accepted for publication in the open-access journal MNRA

Ultrasonic Dispersion and Relaxation in Morpholine

In order to rationalize the influence of FeIII contamination on labeling with the 68Ga eluted from 68Ge/68Ga-generator, a detailed investigation was carried out on the equilibrium properties, formation and dissociation kinetics of GaIII- and FeIII-complexes of 1,4,7-triazacyclononane-1,4,7-tris(methylene[2-carboxyethylphosphinic acid]) (H6TRAP). The stability and protonation constants of the [Fe(TRAP)]3− complex were determined by pH-potentiometry and spectrophotometry by following the competition reaction between the TRAP ligand and benzhydroxamic acid (0.15 M NaNO3, 25°C). The formation rates of [Fe(TRAP)] and [Ga(TRAP)] complexes were determined by spectrophotometry and 31P-NMR spectroscopy in the pH range 4.5–6.5 in the presence of 5–40 fold HxTRAP(x−6) excess (x = 1 and 2, 0.15 M NaNO3, 25°C). The kinetic inertness of [Fe(TRAP)]3− and [Ga(TRAP)]3− was examined by the trans-chelation reactions with 10 to 20-fold excess of HxHBED(x−4) ligand by spectrophotometry at 25°C in 0.15 M NaCl (x = 0,1 and 2). The stability constant of [Fe(TRAP)]3− (logKFeL = 26.7) is very similar to that of [Ga(TRAP)]3− (logKGaL = 26.2). The rates of ligand exchange reaction of [Fe(TRAP)]3− and [Ga(TRAP)]3− with HxHBED(x−4) are similar. The reactions take place quite slowly via spontaneous dissociation of [M(TRAP)]3−, [M(TRAP)OH]4− and [M(TRAP)(OH)2]5− species. Dissociation half-lives (t1/2) of [Fe(TRAP)]3− and [Ga(TRAP)]3− complexes are 1.1 × 105 and 1.4 × 105 h at pH = 7.4 and 25°C. The formation reactions of [Fe(TRAP)]3− and [Ga(TRAP)]3− are also slow due to the formation of the unusually stable monoprotonated [*M(HTRAP)]2− intermediates [*logKGa(HL) = 10.4 and *logKFe(HL) = 9.9], which are much more stable than the [*Ga(HNOTA)]+ intermediate [*logKGa(HL) = 4.2]. Deprotonation and transformation of the monoprotonated [*M(HTRAP)]2− intermediates into the final complex occur via OH−-assisted reactions. Rate constants (kOH) characterizing the OH−-driven deprotonation and transformation of [* Ga(HTRAP)]2− and [*Fe(HTRAP)]2− intermediates are 1.4 × 105 M−1s−1 and 3.4 × 104 M−1s−1, respectively. In conclusion, the equilibrium and kinetic properties of [Fe(TRAP)] and [Ga(TRAP)] complexes are remarkably similar due to the close physico-chemical properties of FeIII and GaIII-ions. However, a slightly faster formation of [Ga(TRAP)] over [Fe(TRAP)] provides a rationale for a previously observed, selective complexation of 68GaIII in presence of excess FeIII

Optimising the relaxivities of Mn2+ complexes by targeting human serum albumin (HSA)

[Abstract] We report two novel macrocyclic ligands based on the 1,4-DO2AM platform (1,4-DO2AM = 2,2′-(1,4,7,10-tetraazacyclododecane-1,4-diyl)diacetamide) and containing two benzyl groups attached either to the nitrogen atoms of the macrocyclic unit (1,4-BzDO2AM) or to the amide pendant arms (1,4-DO2AMBz). The protonation constants of the ligands and the stability constants of their Mn2+ complexes were determined using pH potentiometry. The introduction of benzyl groups results in a slight decrease of the stability constants of the Mn2+ complexes and a slight increase of their acid-catalysed dissociation reactions. A detailed relaxometric characterisation of the complexes using nuclear magnetic dispersion relaxation (NMRD) and 17O NMR studies indicated that the increase in molecular weight associated with the presence of benzyl groups results in a remarkable increase of proton relaxivities r1p, which take values of 3.8, 3.5 and 2.5 mM−1 s−1 for [Mn(1,4-BzDO2AM)]2+, [Mn(1,4-DO2AMBz)]2+ and [Mn(1,4-DO2AM)]2+ (at 25 °C and 20 MHz). The [Mn(1,4-BzDO2AM)]2+ and [Mn(1,4-DO2AMBz)]2+ complexes form relatively strong adducts with Human Serum Albumin (HSA) with association constants of (3.9 ± 0.6) × 103 and (2.0 ± 0.3) × 103 M−1, respectively. The interaction with the protein slows down the rotational tumbling of the complex in solution, which results in adducts endowed with remarkably high proton relaxivities (r1pb = 18.5 ± 0.7 and 27.4 ± 1.4 mM−1 s−1 for [Mn(1,4-BzDO2AM)]2+ and [Mn(1,4-DO2AMBz)]2+, respectively).Ministerio de Economía y Competitivad; CTQ2015-71211-REDTMinisterio de Economía y Competitivad; CTQ2016-76756-

Physico-chemical properties of MnII complexes formed with cis- and trans-DO2A: thermodynamic, electrochemical and kinetic studies

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Nyelőcső-perforatio miatt végzett oesophagusexstirpatio rekonstrukciója hypopharyngogastrostoma képzésével

A sebészi és az intenzív terápia jelentős fejlődése ellenére a nyelőcső-perforatio napjainkban is súlyos, életet veszélyeztető állapot. A háttérben álló kiváltó okok, a kísérő betegségek, a lokalizáció és a kialakuló gyulladás eltérő mértéke miatt néha váratlan szituációval találkozik a sebész. Az 58 éves nőbetegnél a gyomor mellűri inkarcerált herniája miatt kialakult oesophagusperforatio és a következményes nekrotizáló mediastinitis miatt végeztünk oesophagusexstirpatiót, cervicalis oesophagostomiát alakítottunk ki. A tápcsatorna rekonstrukciója során a nyelőcsőcsonk ismeretlen eredetű, teljes hosszát érintő „zsugorodását” találtuk. A csőgyomrot a hypopharynxra anasztomizáltuk, a kialakult insufficientia konzervatív terápiára szanálódott. A beteg komplex nyelésterápia után visszanyerte részleges nyelési képességét. A nem tumoros alapbetegség miatt képzett hypopharyngogastrostoma irodalmi ritkaság. Kényszerhelyzetben, mint amilyen az esetünk is volt, választható műtéti megoldás. A beavatkozást azonban teammunkán alapuló rehabilitációnak kell követnie, amelynek során kiemelt szerepe van a nyelési terápiának

Konzorcium, fő p.: Gravitáció és asztro-részecske fizika = Consortional main: Gravitation and astro-particle physics

Elsősorban az elliptikus pályán keringő kompakt kettősök által keltett gravitációs sugárzást tanulmányoztuk, de foglalkoztunk hiperbolikus pályákon mozgó kettősök által kisugárzott gravitációs hullámok leírásával is. Egy újszerű számítási eljárást fejlesztettünk ki, amivel hatékonyan számolható az, hogy a LISA gravitációs hullámdetektor mennyire pontosan fogja tudni meghatározni a forrás égi pozícióját. Összeolvadó szupermasszív feketelyuk kettősökre kiszámítottuk a mérhető jel/zaj viszony értékeit. A Fisher-analízis segítségével megbecsültük a kettősrendszer paramétereinek relatív hibáit. Kimutattuk, hogy a pálya kezdő excentricitásától lényegesen függenek a paraméterek relatív hibái. Rámutattunk egy újfajta mechanizmusra, ami a földi interferometrikus detektorokkal észlelhető gravitációshullám jelet produkál. Amennyiben a galaxismagokban levő naptömegű fekete lyukak és neutroncsillagok elegendően közel haladnak el egymás mellett, ezek rövid gravitációshullám felvillanásokat generálnak, s megmutattuk, hogy ezen jelek gyakorisága összemérhető a többi forráséval. Lassan forgó csillagok anyagát leíró lehetséges fizikai állapotegyenletek egy nagy osztályára megmutattuk, hogy a kvadrupólus momentum mindig nagyobb, mint amilyen a megfelelő Kerr megoldás kvadrupólus momentuma. Magnetárok környezetében gyorsuló protonok pion sugárzását vizsgáltuk, figyelembevéve a téridő görbületét, s megmutattuk, hogy az a magnetár felszínéről kirepülő protonok energiáját lényegesen befolyásolja. | We have most intensively studied gravitational radiation emitted by compact binary systems, but have also considered gravitational wave emission by binaries on hyperbolic orbits. A new computational method has been developed making the precise determination of the source’s celestial position very effective by LISA. For coalescing supermassive black hole binaries the measurable signal to noise ratio has been computed. By a Fisher-type analysis we have estimated the relative errors of the parameters of the binaries and have shown that these relative errors strongly depend on the initial eccentricity. We have found a new mechanism producing gravitational wave signals originating from close encounters by the black holes and neutron stars present in galactic cores measurable by earth-based interferometric detectors. These close encounters generate gravitational wave bursts, and the expected signal is comparable to all others hitherto known. It has been demonstrated that for a very large class of physical equations of state, the quadrupole moment of slowly rotating stars is always greater than that of the corresponding Kerr black hole. The pion radiation by protons accelerating near magnetars has been studied taking into account the curvature of space-time. It has been found that space-time geometry influences the energy of the protons significantly