Experimental and theoretical spectroscopic studies on selected igepals

Several nonionic igepals characterized by the formula (CmH2m+1 )-C6H4-(OCH2CH2 ) n OH were investigated by high resolution NMR and IR spectroscopy. Gauge invariant atomic orbital density functional theory NMR calculations on model molecules in the gas phase additionally supported the assignment of experimental carbon signals. Different orientations of individual sub-units of an aliphatic chain relative to external magnetic field and trans-gαuche transitions were assumed to explain complex patterns of carbon spectra in the aliphatic region of igepals with linear alkyl chain

Electronic Structure and X-Ray Photoemission Spectra of MPtSn (M = Ti, Zr, Hf)

The electronic structures of the half-Heusler isostructural compounds TiPtSn, ZrPtSn and HfPtSn were calculated and measured applying the X-ray photoemission spectroscopy. The (Ti, Zr, Hf)PtSn compounds have gaps between the occupied valence band and the empty conduction band, calculated as about 0.75, 1.12, and 1.09 eV, respectively. The calculations were done by the full-potential local orbitals method in the framework of the local spin-density approximation and partly also by the full-potential linear mu±n-tin orbitals method by the LmtART code. Experimental X-ray photoemission spectra were measured using photons of en- ergy of 1486.6 eV. The experimental and calculated spectra match quite well except a small shift in the energy scale

Mechanism of action of noradrenaline on secretion of progesterone and oxytocin by the bovine corpus luteum in vitro

The present studies were conducted: (1) to determine which β-adrenoceptor subtypes are involved in progesterone and oxytocin (OT) secretion, (2) to examine whether noradrenaline (NA) acts directly on the cytochrome P-450scc and 3β-hydroxysteroid dehydrogenase (3β-HSD), and (3) to study the effect of prostaglandin F2α, (PGF2α) on NA-stimulated steroidogenesis in luteal cells. The effect of NA on progesterone secretion from luteal slices of heifers on days 8–12 of the oestrous cycle was blocked by both atenolol (β1-antagonist) and ICI 118.551 hydrochloride (β2-antagonist). OT secretion was blocked only after treatment with ICI 118.551 hydrochloride (P < 0.05). Dobutamine (10−410−6), a selective β1 agonist and salbutamol (10−4−10−6), a selective β2 agonist, both increased progesterone production (P < 0.01) with an efficiency comparable to that produced by NA (P < 0.01). The increase of OT content in luteal slices was observed only after treatment with salbutamol at the dose of 10−5M (P < 0.01). Dobutamine had no effect on OT production at any dose. A stimulatory effect of NA on cytochrome P-450scc activity (P < 0.05) was demonstrated using 25-hydroxycholesterol as substrate. 3β-HSD activity also increased following NA (P < 0.01) or pregnenolone (P < 0.05) and in tissue treated with pregnenolone together with NA (P < 0.01). PGF decreased progesterone synthesis (P < 0.05) and 3β-HSD activity (P < 0.01) in tissue treated with NA. We conclude that NA stimulates progesterone secretion by luteal β1- and β2-adrenoceptors, while OT secretion is probably mediated only via the β2-receptor. NA also increases cytochrome P-450scc and 3β-HSD activity. PGF inhibits the luteotropic effect of NA on the luteal tissue

Applying plant lectins to assay the effect of environmental pollution on the glycosylation of human placenta

Our study was designed to establish whether air pollution in urbanized industrial centers of southern Poland affects the process of glycosylation in a full-term human placenta. This process of glycosylation was analyzed by the quantitative determination of the binding of WGA and LCA lectins to placental villi. The study was performed on human placentas collected in 1990-91 and 2000-01 in regions of southern Poland differing in their degree of environmental pollution: the highly polluted areas of Upper Silesia and Cracow agglomeration. The Bieszczady area with low pollution was considered the control. The concentrations of nitrogen and sulfur oxides and the concentration of aerosols were used as markers of the degree of air pollution. The direct immunofluorescence reaction of the placenta tissues with fluorescein-labeled (FITC) lec-tins was used. The staining of the placenta tissues was examined under a fluorescence microscope linked to an analysis system. A microdensytometric method was used to assay the amount of tissue-bound lectins. The results showed no significant effect of the three main air pollutants in the study areas in southern Poland, i.e. nitrogen and sulfur oxides and high level of aerosols, on the structure of WGA-and LCA-specific glycoconjugates in human placenta. However, the marked quantitative changes in th

Can solid body destruction explain abundance discrepancies in planetary nebulae?

In planetary nebulae, abundances of oxygen and other heavy elements derived from optical recombination lines are systematically higher than those derived from collisionally excited lines. We investigate the hypothesis that the destruction of solid bodies may produce pockets of cool, high-metallicity gas that could explain these abundance discrepancies. Under the assumption of maximally efficient radiative ablation, we derive two fundamental constraints that the solid bodies must satisfy in order that their evaporation during the planetary nebula phase should generate a high enough gas phase metallicity. A local constraint implies that the bodies must be larger than tens of meters, while a global constraint implies that the total mass of the solid body reservoir must exceed a few hundredths of a solar mass. This mass greatly exceeds the mass of any population of comets or large debris particles expected to be found orbiting evolved low- to intermediate-mass stars. We therefore conclude that contemporaneous solid body destruction cannot explain the observed abundance discrepancies in planetary nebulae. However, similar arguments applied to the sublimation of solid bodies during the preceding asymptotic giant branch (AGB) phase do not lead to such a clear-cut conclusion. In this case, the required reservoir of volatile solids is only one ten-thousandth of a solar mass, which is comparable to the most massive debris disks observed around solar-type stars, implying that this mechanism may contribute to abundance discrepancies in at least some planetary nebulae, so long as mixing of the high metallicity gas is inefficient.Comment: 8 pages, no figures, ApJ in pres

The Massive Stellar Content in the Starburst NGC3049: A Test for Hot-Star Mode

We have obtained high-spatial resolution ultraviolet and optical STIS spectroscopy and imaging of the metal-rich nuclear starburst in NGC3049. The stellar continuum and the absorption line spectrum in the ultraviolet are used to constrain the massive stellar population. The strong, blueshifted stellar lines of CIV and SiIV detected in the UV spectra indicate a metal-rich, compact, massive (1E6 Msol) cluster of age 3--4 Myr emitting the UV-optical continuum. We find strong evidence against a depletion of massive stars in this metal-rich cluster. The derived age and the upper mass-limit cut-off of the initial mass function are also consistent with the detection of Wolf-Rayet (WR) features at optical wavelengths. As a second independentconstraint on the massive stellar content, the nebular emission-line spectrum is modeled with photoionization codes using stellar spectra from evolutionary synthesis models. However, the nebular lines are badly reproduced by 3--4 Myr instantaneous bursts, as required by the UV line spectrum, when unblanketed WR and/or Kurucz stellar atmospheres are used. The corresponding number of photons above 24 and 54 eV in the synthetic models is too high in comparison with values suggested by the observed line ratios. Since the ionizing spectrum in this regime is dominated by emission from WR stars, this discrepancy between observations and models is most likely the result of incorrect assumptions about the WR stars. Thus we conclude that the nebular spectrum of high-metallicity starbursts is poorly reproduced by models for WR dominated populations. However, the new model set of Smith et al. (2002) with blanketed WR and O atmospheres and adjusted WR temperatures predicts a softer far-UV radiation field, providing a better match to the data.Comment: To be published in ApJ, Dec. issue 17 figures, 3 in gif forma

Czy nie-HDL cholesterol lepiej niż cholesterol frakcji LDL odzwierciedla ryzyko sercowo-naczyniowe?

The concentration of lipids and lipoproteins in plasma is essential in the treatment of lipid disorders. The routine lipidpanel includes total cholesterol, triglycerides, cholesterol of low-density lipoprotein (LDL-C) and cholesterol of high--density lipoprotein (HDL-C). The latest guidelines of the European Society of Cardiology (valid until 2020) indicate thatbesides many players in the lipid arena (apolipoprotein, concentration and size of LDL particles) another parameter,non-HDL-cholesterol (non-HDL-C), is very important. This parameter, being easily available for routine clinical use, hasbeen highlighted as a key secondary goal of therapy in patients with cardiometabolic risk.Non-HDL-C is a superior parameter to LDL-C, especially the one estimated using Friedewald formula for prediction of cardiovascular events, because non-HDL-C is an integrated complex of all lipoprotein particles containing apolipoprotein B,i.e.: LDL, very low-density lipoproteins, intermediate-density lipoproteins, chylomicrons, remnants and Lp(a). Crucially, itcan be calculated directly from the values of routine lipid panels, without additional cost.In our opinion, non-HDL-C should be presented in all routine lipid profiles conducted by diagnostic laboratories. Wealso propose a new presentation of the results of routine lipid panel, which allows a significant change in treatmentgoals, taking into account the hierarchy of values of individual concentrations of lipoprotein fractions and how they areinterpreted in the management of dyslipidaemia for optimal prevention of atherosclerosis and cardiovascular diseases.W leczeniu zaburzeń lipidowych zasadnicze znaczenie ma stężenie lipidów i lipoprotein osocza. Rutynowy panel lipidowy obejmuje: cholesterol całkowity, triglicerydy, cholesterol frakcji lipoprotein o niskiej gęstości (LDL-C) oraz cholesterol frakcji lipoprotein o wysokiej gęstości (HDL-C). W najnowszych wytycznych Europejskiego Towarzystwa Kardiologicznego (obowiązujące do 2020 r.) wskazano, że oprócz licznych parametrów na arenie lipidowej (apolipoproteiny, stężenie i wielkość cząstek LDL) niezwykle istotny jest kolejny parametr — cholesterol nie-HDL. Ten łatwo dostępny do rutynowego zastosowania klinicznego parametr wyróżniono jako kluczowy drugorzędowyy cel terapii u pacjentów obciążonych ryzykiem kardiometabolicznym. Cholesterol nie-HDL (nie-HDL-C) jest lepszym parametrem niż LDL-C, szczególnie gdy jest wyliczany zgodnie ze wzorem Friedewalda w przewidywaniu zdarzeń sercowo-naczyniowych, ponieważ nie-HDL-C jest zintegrowanym kompleksem wszystkich cząstek lipoprotein zawierających apolipoproteinę B, czyli: LDL, VLDL, IDL, chylomikrony, remnanty oraz lipoproteinę (a). Można go obliczyć bezpośrednio z wartości rutynowych paneli lipidowych bez dodatkowych kosztów. W opinii autorów nie-HDL-C powinien być prezentowany we wszystkich rutynowych profilach lipidowych wykonywanych w medycznych laboratoriach diagnostycznych. Zaproponowano również nową prezentację wyników rutynowego panelu lipidowego, która pozwala na istotną zmianę celów leczenia, biorąc pod uwagę hierarchię wartości stężeń poszczególnych frakcji lipoprotein i sposób ich interpretacji w zarządzaniu dyslipidemią w celu optymalnego zapobiegania miażdżycy i chorobom układu sercowo-naczyniowego

Czy nie-HDL cholesterol lepiej niż cholesterol frakcji LDL odzwierciedla ryzyko sercowo-naczyniowe?

W leczeniu zaburzeń lipidowych zasadnicze znaczenie ma stężenie lipidów i lipoprotein osocza. Rutynowy panel lipidowy obejmuje: cholesterol całkowity, triglicerydy, cholesterol frakcji lipoprotein o niskiej gęstości (LDL-C) oraz cholesterol frakcji lipoprotein o wysokiej gęstości (HDL-C). W najnowszych wytycznych Europejskiego Towarzystwa Kardiologicznego (obowiązujące do 2020 r.) wskazano, że oprócz licznych parametrów na arenie lipidowej (apolipoproteiny, stężenie i wielkość cząstek LDL) niezwykle istotny jest kolejny parametr — cholesterol nie-HDL. Ten łatwo dostępny do rutynowego zastosowania klinicznego parametr wyróżniono jako kluczowy drugorzędowyy cel terapii u pacjentów obciążonych ryzykiem kardiometabolicznym. Cholesterol nie-HDL (nie-HDL-C) jest lepszym parametrem niż LDL-C, szczególnie gdy jest wyliczany zgodnie ze wzorem Friedewalda w przewidywaniu zdarzeń sercowo-naczyniowych, ponieważ nie-HDL-C jest zintegrowanym kompleksem wszystkich cząstek lipoprotein zawierających apolipoproteinę B, czyli: LDL, VLDL, IDL, chylomikrony, remnanty oraz lipoproteinę (a). Można go obliczyć bezpośrednio z wartości rutynowych paneli lipidowych bez dodatkowych kosztów. W opinii autorów nie-HDL-C powinien być prezentowany we wszystkich rutynowych profilach lipidowych wykonywanych w medycznych laboratoriach diagnostycznych. Zaproponowano również nową prezentację wyników rutynowego panelu lipidowego, która pozwala na istotną zmianę celów leczenia, biorąc pod uwagę hierarchię wartości stężeń poszczególnych frakcji lipoprotein i sposób ich interpretacji w zarządzaniu dyslipidemią w celu optymalnego zapobiegania miażdżycy i chorobom układu sercowo-naczyniowego

Dynamics of hormonal disorders following unilateral orchiectomy for a testicular tumor

Testicular tumors and their treatment interfere with homeostasis, hormonal status included. The aim of the study was to evaluate hormonal disorders of the pituitary–gonadal axis in men treated for testicular tumors. One hundred twenty-eight men treated for a unilateral testicular tumor at our institution were included. The hormonal status was prospectively evaluated in 62 patients before orchiectomy, 120 patients 1 month after orchiectomy and 110 patients at least 1 year after the treatment. The concentrations of human chorionic gonadotropin (hCG), testosterone (T), estradiol, luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin were measured. The clinically significant testosterone deficiency was defined either as testosterone <2.31 ng/mL or testosterone within the range of 2.31–3.46 ng/mL but simultaneous with T/LH ratio ≤1. Changes in hormone levels were significant: LH and FSH rose in the course of observation, and the concentration of hCG, testosterone, estradiol decreased. PRL concentration was the lowest at 1 month after orchiectomy. In multivariate analysis, the risk of the clinically significant testosterone deficiency was 0.2107 (95% CI 0.1206–0.3419) prior to orchiectomy, 0.3894 (95% CI 0.2983–0.4889) 1 month after surgery and 0.4972 (95% CI 0.3951–0.5995) 1 year after the treatment. The estradiol concentration was elevated in 40% of patients with recently diagnosed testicular cancer and that was correlated with a higher risk of testosterone deficiency after the treatment completion. Hormonal disorders of the pituitary–gonadal axis in men treated for testicular tumors are frequent. The malignant tissue triggers paraneoplastic disorders that additionally disturb the hormonal equilibrium