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Background Bowel preparation prior to colonoscopy is a routine procedure and supposed to be safe. However, the exacerbation of the complaints could be observed in numerous cases after colonoscopy in patients with inflammatory bowel disease (IBD, Crohn’s disease CD, ulcerative colitis UC). Therefore, our study aimed to investigate the short- and long-term changes of the fecal microbiota composition influenced by the bowel preparation with sodium-picosulphate and magnesium-oxide. Methods IBD patients (inactive or mild) preparing for colonoscopy with bowel preparation were enrolled in the study. Control group (HC) consisted of non-IBD patients who were recommended to undergo colonoscopy due to abdominal complaints. Clinical data, blood and stool samples were collected before colonoscopy (point A), 3 days later (point B) and 4 weeks later (point C) to assess disease activity and the changes of the gut microbiome. Fecal microbiota structure was determined by sequencing V4 region of the 16S rRNA gene. Microbiome structure was determined at family level. Statistical analysis included differential abundance analysis and Mann-Whitney test, values of p Results 41 patients (9 CD, 13 UC, 19 HC) were enrolled in our study. After the bowel preparation, alpha diversity in the CD group was lower compared to UC(p=0.01) and control(p=0.02) patients at point B. Alpha diversity of UC patients was significantly higher than CD (p‹0.01) and control (p=0.03) groups at point C. Alpha diversity of UC patients increased from point A to C (p=0.04). However, a decreasing tendency in alpha diversity was observed in patients with CD at A to C period (p=0.26). These changes couldn’t be observed in the control group. Beta diversity showed slight differences between the IBD groups and the control group. After bowel preparation, beta diversity of CD patients immediately (from A to B) changed p=0.03), while beta diversity of UC patients seems to continually change from point A to C(p=0.03). Based on the differential abundance analysis, Clostridiales and Pseudomonadaceae families increased, while Bifidobacteriaceae, Carnobacteriaceae, Veillonellaceae and Pasteurellaceae families decreased in CD patients compared to the HC at point B. The most growing families in HC group were Brucellaceae, Moraxellaceae and Alcaligenaceae at A to B period. Conclusion Our findings may suggest that bowel preparation can result in a significant change in faecal microbial composition in IBD. Microbial alterations recovering earlier in UC patients due to changed mucosa. Reduced alpha diversity and altered abundance in CD may have potential role in disease exacerbation. Further examinations are needed to clarify our pilot results.

The effective anisotropy of Co-based nanowires such as CoFe, monocrystalline hcp Co and polycrystalline Co with a mixture of fcc and hcp grains has been evaluated through micromagnetic modeling based on the magnetization torque simulations. We retrieve the experimental profile of the torque curves and show that the non-harmonic forms observed at low fields correspond to the presence of open vortices at the nanowire ends. Our results show that strong hcp anisotropy of Co cannot overcome the uniaxial character of the effective anisotropy which always remains parallel to the nanowire axis, even in the case of magnetocrystalline easy axis perpendicular to the nanowire. We evaluate effective anisotropy values for monocrystalline Co nanowires with different easy axis orientations and polycrystalline Co nanowires with different mixtures of hcp and fcc grains., Work supported by the Romanian Executive Agency for Higher Education, Research, Development and Innovation Funding (UEFISCCDI) under project PN 16 37 02 02 (Nucleu Program) and by the European Commission under Grant no. 316194 (NANOSENS). The work of R.M., N.N., M.V and O.C. F was partially supported by Spanish MINECO Grant MAT2016-76824-C3-1-R, MAT2014-52405-C02-02 and MAT2013-48054-C2-1-R. The work of T.F. was partially supported by the Hungarian research fund OTKA K 107228.

Using ferromagnetic resonance spectroscopy at 34 GHz we explored the magnetic anisotropy of single-crystalline GaV

Greater than normal bone mineral content, bone width of the radius measured by photon absorptiometry and bone mineral content to bone width ratio found in women with hyperostosis frontalis interna pointed on a generalized alteration of the skeletal system. An increase in serum dehydroepiandosterone, its sulphate and testosterone levels and a significant correlation between serum free dehydroepiandosterone and bone mineral content in subjects without any sign of hirsutism or obesity suggested an involvement of androgens in pathogenesis of this metabolic bone disorder.

To assess the validity of serum dehydroepiandrosterone sulphate (DS) radioimmunoassay instead of urinary total 17-ketosteroid (17-KS) or individual metabolite (dehydroepiandrosterone + etiocholanolone + androsterone; D + E + A) determination to control adrenal androgen function, a comparative study has been performed. Mathematical analysis of simultaneous estimates revealed significant correlation when normal or above normal 17-KS or D + E + A excretion relative to serum DS were considered. Poor correlation was observed when below normal metabolite excretion and serum DS were related. Furthermore, there was a significant correlation between estimates of 17-KS (or D + E + A) and those of serum unconjugated D also determined by radioimmunoassay. The serum DS radioimmunoassay appeared to be a reliable tool to assess adrenal androgen function, at least in patients exhibiting normal or high 17-ketosteroid values.

In the present work the correlation between the immunological parameters and plasma androgen hormone levels in rheumatoid arthritis (RA) was examined. Female patients were divided in groups according to their age and immunologic state. Plasma dehydroepiandrosterone (D), D sulphate (DS), and testosterone (T) levels were determined by radioimmunological methods. The values were related first to those of normal controls. The T and DS levels were significantly decreased in all patient groups examined, the D level was low only in "Rf+ active" state aged 18 to 45 years. Furthermore, it was examined whether the decreased hormone levels were in relationship either with the autoantibody (Rf) formation or with the activity of the disease. According to the observations the T levels were influenced neither by the autoantibody formation nor by the activity of the disease. The DS and D levels appeared to correlate both with the autoantibody formation and the activity of the disease, particularly in young patients, being significantly low in the "Rf+ active" state. From these we concluded that the condition of the immune system has an influence on the sex hormone and/or adrenal androgen function.

We report new results on the electron spin resonance of single walled carbon nanotubes, peapods and double walled carbon nanotubes. A small ESR line is present in well purified samples and its temperature dependence reveals a striking 'super-Curie' paramagnetic rise. In addition, we identify a narrower line in peapod and DWNT samples, which displays similar behavior. The linewidth of both inner and outer species are metallic and the outer tube's resonance broadens upon growth of the inner tubes. We observe a sudden decrease of relaxation rate below 20 K, in accordance with the opening of a spin-gap.

Doping the high- ${T}_{c}$ superconductor ${\mathrm{YBa}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6.7}$ with $1.5%$ of nonmagnetic Zn impurities in ${\mathrm{CuO}}_{2}$ planes is shown to produce a considerable broadening of ${}^{63}\mathrm{Cu}$ NMR spectra, as well as an increase of low-energy magnetic fluctuations detected in ${}^{63}\mathrm{Cu}$ spin-lattice relaxation measurements. A model-independent analysis demonstrates that these effects are due to the development of staggered magnetic moments on many Cu sites around each Zn and that the Zn-induced moment in the bulk susceptibility might be explained by this staggered magnetization. Several implications of these enhanced antiferromagnetic correlations are discussed.

After cyclodextrin-coated 10 −6 m steroid hormone treatment for 3 days (hormonal imprinting), Tetrahymena cells and their media were analysed by radioimmunoassay for the same hormone and for the presence of the other two. In the absence of hormone treatment, the cells contained no detectable levels of the three steroids. By 2 days in fresh medium following exposure of cells to a 72 h pretreatment of each specific hormone, correspondingly high quantities of hydrocortisone and oestradiol, but lesser quantities of testosterone, were found in both the media and the cells. One week after treatment only traces of hydrocortisone were found, exclusively within the cells themselves. Oestradiol was present in measurable quantities in both cells and media, whereas testosterone was only present in the medium. The presence of the other two hormones to the one used in the pretreatment were not usually present, except that when testosterone had been given, some oestradiol was also detected at 48 h, suggesting Tetrahymena has a functional cytochrome P 450 aromatase.

This paper investigates the effect of the ITER-like wall (ILW) on Runaway Electron (RE) generationthrough a comparative study of similar slow argon injection JET disruptions, performed with different wall materials. In the carbon wall case, a runaway electron plateau is observed, while in the ITER-like wall case, the current quench is slower and the runaway current is negligibly small. The aim of the paper is to shed light on the reason for these differences by detailed numerical modelling to study which factors affected the RE formation. The post-disruption current profile is calculated by a onedimensional model of electric field, temperature and runaway current taking into account the impurity injection. Scans of various impurity contents are performed and agreement with the experimental scenarios is obtained for reasonable argon- and wall impurity contents. Our modelling shows that the reason for the changed RE dynamics is a complex, combined effect of the differences in plasma parameter profiles, the radiation characteristics of beryllium and carbon, and the difference of the injected argon amount. These together lead to a significantly higher Dreicer generation rate in the carbon wall case, which is less prone to be suppressed by RE loss mechanisms. The results indicate that the differences are greatly reduced above ~50% argon content, suggesting that significant RE current is expected in future massive gas injection experiments on both JET and ITER.

Runaway electrons (RE) with energies of several megaelectronvolts have been observed during disruptions in JET and other large tokamaks. These intense electron beams are the result of the toroidal electric field induced by the sudden cooling in connection with disruptions and may cause severe damage to the plasma facing components. Therefore REs are considered to be a potential threat to the operation of tokamaks with high currents, such as ITER. Reliable runaway electron (RE) mitigation after disruptions is one of the most important challenges for safe ITER operation. A proper understanding of the generation and loss of REs is therefore essential. This paper investigates the effect of the ITER-like wall (ILW) on RE generation in JET. The ILW comprises solid beryllium limiters and a combination of bulk tungsten and tungsten-coated carbon fibre composite divertor tiles. Similar JET disruptions in Lmode limiter discharges are compared with different wall materials: carbon (Carbon Fibre Composite, CFC) and beryllium (for ILW). In both cases the disruption was induced by slow argon injection. Typically with the ILW, a significantly lower fraction of energy is radiated during the disruption process, yielding higher plasma temperatures after the thermal quench and thus longer current quench times. As a consequence, in the carbon wall case, a runaway electron plateau is observed, while with the ILW the runaway current is negligibly small. Runaway electron dynamics is a complicated process, therefore numerical modelling is necessary to provide a deeper insight into the physics. Detailed modelling was carried out to study which factors affected the RE formation in these two cases.

Joining peptide 1-18 (JP 1-18), added alone in concentrations of 10 −13 –10 −7 M to collagenase-dispersed human adrenocortical cells, did not affect the basal production of corticosterone, cortisol, aldosterone, dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS). JP 1-18 potentiated the ACTH-stimulated production of steroids. When administered in combination with histamine (10 −8 –10 −3 M), JP 1-18 (10 −8 or 10 −10 M), enhanced the synthesis of DHEA and DHEAS. JP 1-18, together with histamine, may play a role in the regulation of DHEA and DHEAS production.

We studied spin excitations in the magnetically ordered phase of the noncentrosymmetric Ba(2)CoGe(2)O(7) in high magnetic fields up to 33 T. In the electron spin resonance and far infrared absorption spectra we found several spin excitations beyond the two conventional magnon modes expected for such a two-sublattice antiferromagnet. We show that a multiboson spin-wave theory describes these unconventional modes, including spin-stretching modes, characterized by an oscillating magnetic dipole and quadrupole moment. The lack of inversion symmetry allows each mode to become electric dipole active. We expect that the spin-stretching modes can be generally observed in inelastic neutron scattering and light absorption experiments in a broad class of ordered S1/2 spin systems with strong single-ion anisotropy and/or noncentrosymmetric lattice structure.

Adrenal androgens, dehydroepiandrosterone, its sulphate and, in comparison, cortisol in serum were determined over two periods in red deer. The hormone levels were determined in hinds farmed from their births, captured in adulthood, and in fawns reared under farm conditions with their mothers or under artificial farm conditions without their mothers. In addition, steroid levels were studied in stags under farm conditions in and after the breeding season. Investigation of animals for their potential as farmed animals gave information on the stress susceptibility. It is suggested that the present assessment of hormonal events will provide prognostic information on their adaptation to farm conditions, reproductive performance, and possibly, their immune responses and the quality of their products.

Several series of data suggest that alterations in adrenal androgen output might be a contributing factor to changes in bone mass. To study the possible relationship between bone density and serum levels of dehydroepiandrosterone sulphate (DHEAS) we investigated 105 women (aged 45–69 years; 76 postmenopausal, 29 perimenopausal). The patients were divided into two groups according to the bone mineral density (BMD) measurement (normal densityn=50, low densityn=55). BMD was measured by dual-energy X-ray absorptiometry of the lumbar spine and femoral neck. Bone mineral content (BMC) of the radius midshaft was measured by single photon absorptiometry. Serum DHEAS level was significantly lower in the ‘low density’ group than in the ‘normal’ one (1.91±1.04 v 4.77±2.03 µmol/l,p

We report the development of the frequency-modulation (FM) method for measuring electron spin resonance (ESR) absorption in the 210-420 GHz frequency range. We demonstrate that using a high-frequency ESR spectrometer without resonating microwave components enables us to overcome technical difficulties associated with the FM method due to nonlinear microwave-elements, without sacrificing spectrometer performance. FM was achieved by modulating the reference oscillator of a 13 GHz Phase Locked Dielectric Resonator Oscillator, and amplifying and frequency-multiplying the resulting millimeter-wave radiation up to 210, 315 and 420 GHz. ESR spectra were obtained in reflection mode by a lock-in detection at the fundamental modulation frequency, and also at the second and third harmonic. Sensitivity of the setup was verified by conduction electron spin resonance measurement in KC$_{60}$., 4 pages, 5 figures

International audience; In LiNiO2, the Ni3+ ions, with S=1/2 and twofold orbital degeneracy, are arranged on a trian- gular lattice. Using muon spin relaxation (MuSR) and electron spin resonance (ESR), we show that magnesium doping does not stabilize any magnetic or orbital order, despite the absence of interplane Ni2+. A disordered, slowly fluctuating state develops below 12 K. In addition, we find that magnons are excited on the time scale of the ESR experiment. At the same time, a g factor anisotropy is observed, in agreement with $\vert 3z^{2}-r^{2}\rangle$ orbital occupancy.

We present a newly-developed microwave probe for performing sensitive high-field/multi-frequency electron spin resonance (ESR) measurements under high hydrostatic pressures. The system consists of a BeCu-made pressure-resistant vessel, which accommodates the investigated sample and a diamond microwave coupling window. The probe's interior is completely filled with a pressure-transmitting fluid. The setup operates in reflection mode and can easily be assembled with a standard oversized microwave circuitry. The probe-head withstands hydrostatic pressures up to 1.6 GPa and interfaces with our home-built quasi-optical high-field ESR facility, operating in a millimeter/submillimeter frequency range of 105-420 GHz and in magnetic fields up to 16 T. The overall performance of the probe was tested, while studying the pressure-induced changes in the spin-relaxation mechanisms of a quasi-1D conducting polymer, KC(60). The preliminary measurements revealed that the probe yields similar signal-to-noise ratio to that of commercially available low-frequency ESR spectrometers. Moreover, by observing the conduction electron spin resonance (CESR) linewidth broadening for KC(60) in an unprecedented microwave frequency range of 210-420 GHz and in the pressure range of up to 1.6 GPa, we demonstrate that a combination of high-pressure ESR probe and high-field/multi-frequency spectrometer allows us to measure the spin relaxation rates in conducting spin systems, like the quasi-1D conductor, KC(60).

Refuelling of fusion plasmas by the injection of frozen hydrogen isotope pellets from the magnetic high field side (HFS) rather than from the low field side (LFS) increases the fuelling efficiency due to the gradBdrift accelerating the ablatant material in the positive major radius direction, thus towards the centre of the plasma. The HFS pellet fuelling is therefore presently established as the main fuelling scenario for ITER. This paper describes an HFS pellet database developed at the ASDEX Upgrade tokamak and the HFS penetration depth scaling derived by statistical analysis performed on the dataset. Also a comparison is made with the existing empirical LFS penetration depth scaling and theoretical models.

C1 inhibitor (C1inh), a member of the serine protease inhibitor gene superfamily, is a glycosylated plasma protein inhibiting the proteolytic activities of C1r and C1s and involved in the regulation of coagulation, fibrinolysis and kinin-releasing systems. In this study, the in vitro effect of androgen hormones, dehydroepiandrosterone (DHEA), testosterone (TEST) and recombinant human gamma-interferon (gamma-IFN), has been determined on the production of C1inh in human cell lines. In both human monocytoid/histiocytoid cell line U937 and in hepatoma derived cell line HepG2, DHEA and TEST upregulated the gene expression and secretion of C1inh. The most pronounced effect was detected in the concn range 10(-7)-10(-9) M of the hormones. Under the same conditions DHEA and TEST had no detectable effect on the biosynthesis of C3, C2 and factor B by these cells, but DHEA at higher concn (10(-4) M) slightly increased that of C4 in HepG2 cells. Both in U937 and in HepG2 cells recombinant gamma-IFN markedly increased the gene expression and secretion of C1inh. This effect of gamma-IFN was abolished by histamine.

We present a series of electron spin resonance (ESR) and infrared transmission experiments in antiferromagnetic (AF), lightly hole-doped $\mathrm{Y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6}$ in search for the effect of a spatially inhomogeneous ground state on the magnetic and electric properties. Crystal compositions were ${\mathrm{Ca}}_{x}{\mathrm{Gd}}_{y}{\mathrm{Y}}_{1\ensuremath{-}x\ensuremath{-}y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{6}$ with $x=0$, 0.008, 0.02, and 0.03 and $y\ensuremath{\approx}0.01$. ${\mathrm{Gd}}^{3+}$ ESR satellites from sites with first-neighbor Ca atoms show that holes are not preferentially localized at low temperatures in the vicinity of Ca dopants. We mapped by multifrequency ${\mathrm{Gd}}^{3+}$ ESR the AF domain structure as a function of hole concentration, temperature, and magnetic fields up to $8\phantom{\rule{0.3em}{0ex}}\mathrm{T}$. We attribute the hole-doping-induced rotation of the magnetic easy axis from collateral to diagonal (with respect to the tetragonal $\mathrm{Cu}{\mathrm{O}}_{2}$ lattice) to the pinning of the AF magnetization to a static modulation or a phase-separated network of the hole density. The dominantly fourfold symmetry of pinning suggests that the hole density network has this symmetry also and is not an array of stripes. At higher temperatures the pinning to the diagonal direction becomes weak and the possibility of domain wall fluctuations is discussed. There is no magnetic field dependence and no in-plane anisotropy of the infrared transmission polarized in the $\mathrm{Cu}{\mathrm{O}}_{2}$ planes in an $x=0.02$ crystal placed in magnetic fields up to $12\phantom{\rule{0.3em}{0ex}}\mathrm{T}$. Thus, the network of holes is rigid and is not affected by magnetic fields that are, however, strong enough to rotate the AF magnetization into a single domain.

C(59)N magnetic fullerenes were formed inside single-wall carbon nanotubes by vacuum annealing functionalized C(59)N molecules encapsulated inside the tubes. A hindered, anisotropic rotation of C(59)N was deduced from the temperature dependence of the electron spin resonance spectra near room temperature. Shortening of the spin-lattice relaxation time T(1) of C(59)N indicates a reversible charge transfer toward the host nanotubes above approximately 350 K. Bound C(59)N-C(60) heterodimers are formed at lower temperatures when C(60) is coencapsulated with the functionalized C(59)N. In the 10-300 K range, T(1) of the heterodimer shows a relaxation dominated by the conduction electrons on the nanotubes.

The photo-oxidative stress in aqueous milieus can readily be generated in the presence of newly synthesized highly derivatized fullerenes (fullerols) reported in the Full Paper by Vileno and co-workers on p. 120. Their basic structural and photophysical properties were characterized using a range of methods, including X-ray photoelectron and IR spectroscopies, and electron spin resonance. Moreover, a significant drop of the local stiffness of a living cell was monitored using atomic force microscopy. This cell softening was attributed to the early effects of the photo-oxidative stress. Hydroxylated C60 molecules, also called fullerols, are a class of water-soluble fullerenes. Here we report the synthesis in acidic conditions of a highly derivatized fullerol (up to 36 carbons per C60 are oxidized). Spectroscopic investigations (X-ray photoelectron spectroscopy and infrared absorption) highlight the coexistence of both acidic and basic forms for the hydroxyl addends of derivatized C60. pH titrimetry reveals that, at millimolar concentrations, only ten protons per fullerol molecule are labile. Such a low value, as compared to 36 hydroxyl groups, is explained by the formation of clusters. A UV-vis absorption study performed over a large range of concentrations also points to the aggregation phenomenon. Moreover, this study shows that the clusters of fullerols appear at relatively low (micromolar) concentrations. An electron spin resonance (ESR) study, based on the attack of singlet oxygen (1Δg) on 2,2,6,6-tetramethyl-4-piperidinol (TMP-OH), has proved the potential of hydroxylated C60 for performing efficient generation of singlet oxygen in aqueous solution. ESR measurements, which allow detection and quantification of 1Δg, have also revealed the generation of reactive oxygen species (ROS). The yield of generation of 1Δg and ROS is strongly correlated to the concentration of fullerol, thus also pointing to the aggregation of fullerol molecules. Exposing glioblastoma cells to oxidative stress in the presence of hydroxylated C60 and visible light has also been performed. Atomic force microscopy is used to monitor the relevant diminishment of the Young's modulus values for cells exposed to the oxidative stress. These results point to a possible application field of fullerols for performing bio-oxidations.

Hydroxylated C60 molecules, also called fullerols, are a class of water-soluble fullerenes. Here we report the synthesis in acidic conditions of a highly derivatized fullerol (up to 36 carbons per C60 are oxidized). Spectroscopic investigations (X-ray photoelectron spectroscopy and infrared absorption) highlight the coexistence of both acidic and basic forms for the hydroxyl addends of derivatized C60. pH titrimetry reveals that, at millimolar concentrations, only ten protons per fullerol molecule are labile. Such a low value, as compared to 36 hydroxyl groups, is explained by the formation of clusters. A UV-vis absorption study performed over a large range of concentrations also points to the aggregation phenomenon. Moreover, this study shows that the clusters of fullerols appear at relatively low (micromolar) concentrations. An electron spin resonance (ESR) study, based on the attack of singlet oxygen (1Δg) on 2,2,6,6-tetramethyl-4-piperidinol (TMP-OH), has proved the potential of hydroxylated C60 for performing efficient generation of singlet oxygen in aqueous solution. ESR measurements, which allow detection and quantification of 1Δg, have also revealed the generation of reactive oxygen species (ROS). The yield of generation of 1Δg and ROS is strongly correlated to the concentration of fullerol, thus also pointing to the aggregation of fullerol molecules. Exposing glioblastoma cells to oxidative stress in the presence of hydroxylated C60 and visible light has also been performed. Atomic force microscopy is used to monitor the relevant diminishment of the Young's modulus values for cells exposed to the oxidative stress. These results point to a possible application field of fullerols for performing bio-oxidations.

It is now generally accepted that MgB2 is a phononmediated superconductor 1–3 which owes its unusual properties to the strong differences in the electron-phonon coupling of its disconnected Fermi surface sheets. 4 The two-gap model assigns a large superconductor gap to the cylindrical Fermi surface sheets originating from B – B bonds and a much smaller gap to the sheets of electrons. The model successfully describes the temperature dependence of several properties like the specific heat 5 or the electron tunneling spectra 6 in zero magnetic field while predictions for finite magnetic fields are less tested. The strong electronphonon coupling on the sheets maintains superconductivity to about Hc2 c 2.5 T for fields perpendicular to and H c2 ab 16 T for fields lying in the crystalline a ,b boron planes. 7 It has been suggested that the weaker gap is closed by much smaller fields H c2 without destroying superconductivity. The actual value of Hc2 is rather uncertain: from single-crystal specific heat experiments 8 an isotropic Hc2 = 0.3– 0.4 T, from vortex imaging 9 0.13 T has been estimated, while point contact tunneling experiments 10–13 suggest values between 1 and 2 T.

International audience; We have studied the electron spin resonance (ESR) of single-walled carbon nanotubes (SWNTs) both in their pristine state and after irradiation with fast electrons in order to detect the signal of conduction electrons. No metallic Pauli contribution was observed in the global spin susceptibility, the ESR signal of the conduction electrons is undetectable because it is broadened by magnetic impurities. We measured a paramagnetic contribution from localized states, with an effective Curie constant decreasing when the temperature increases, following a deactivation law of the type A-B exp(-E-a/k(B)T). This behavior is supposed to be characteristic of semiconducting SWNTs interacting with metallic impurities from the catalyst

We observed the conduction electron spin resonance (CESR) in fine powders of MgB2 both in the superconducting and normal states. The Pauli susceptibility is chi(s) = 2.0 x 10(-5) emu/mole in the temperature range of 450 to 600 K. The spin relaxation rate has an anomalous temperature dependence. The CESR measured below T(c) at several frequencies suggests that MgB2 is a strongly anisotropic superconductor with the upper critical field, H(c2), ranging between 2 and 16 T. The high-field reversible magnetization data of a randomly oriented powder sample are well described assuming that MgB2 is an anisotropic superconductor with H(ab)(c2)/H(c)(c2) approximately 6-9.

After cyclodextrin-coated 10(-6) m steroid hormone treatment for 3 days (hormonal imprinting), Tetrahymena cells and their media were analysed by radioimmunoassay for the same hormone and for the presence of the other two. In the absence of hormone treatment, the cells contained no detectable levels of the three steroids. By 2 days in fresh medium following exposure of cells to a 72 h pretreatment of each specific hormone, correspondingly high quantities of hydrocortisone and oestradiol, but lesser quantities of testosterone, were found in both the media and the cells. One week after treatment only traces of hydrocortisone were found, exclusively within the cells themselves. Oestradiol was present in measurable quantities in both cells and media, whereas testosterone was only present in the medium. The presence of the other two hormones to the one used in the pretreatment were not usually present, except that when testosterone had been given, some oestradiol was also detected at 48 h, suggesting Tetrahymena has a functional cytochrome P(450)aromatase.

The effect exerted by a biogenic performance enhancer of high nucleotide content on meat quality in 20 Norwegian Landrace pigs (90 to 95 kg) was examined. The diet of the treated group was supplemented with the performance enhancer for the last 30 days of fattening. The stress effect was transport to the slaughterhouse and slaughter itself. Plasma creatine kinase (CK), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) activities, glucose and cortisol concentrations, and muscle pH were determined. Serious stress damage was found in the cardiac and skeletal muscle, as indicated by the high CK (980 U/L), LDH (1600 U/L) and AST (67 U/L) activities in the untreated group; values were significantly lower in the experimental pigs (458, 468 and 17 U/L, respectively). There were no significant differences in glucose and cortisol concentrations between the two groups. In the control group the pH values were significantly lower and more muscle samples showed PSE character than in the treated group (75 and 30%, respectively).

The biological function of the since more than 5 decades discovered adrenal dehydroepiandrosterone and dehydroepiandrosterone sulphate we were studied since 1960. A renaissance of these steroids is talking about in last years. The knowledge of the metabolic features and biological effects of the hormone pair has been indispensable for internal, gynecologic and pediatric medicine, as well as for oncologists and immunologists. The present review summarizes our contemporary knowledge on the hormone pair in view of observations reported in the literature and made in our Institute. Recently, Professor Baulieu working in Paris, hypothesized that the supplementation of the gradual physiological decrease of dehydroepiandrosterone sulphate during aging processes may delay the biological events of aging. This may result in an improvement of "the general state of health, brighter and more care-free declining years".

In studies on the adaptation of red deer (Cervus elaphus) to farm conditions, some blood parameters of 3- to 9-year-old captured and farmed hinds were compared. The test variable included blood plasma creatine kinase (CK), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) activities, the concentrations of glucose, urea, total protein (TP), serum cortisol, haemoglobin (Hb), and the blastogenic transformation of lymphocytes upon stimulation by the nonspecific mitogens Phaseolus vulgaris (PHA) and Concanavalin A (ConA) in the lymphocyte stimulation test (LST). The effects exerted by probiotic preparation (Ascogen) on the same parameters were studied in farmed deer. In hinds that had been kept under farm conditions for 10 months, CK activity was lower (P0.05) and blood urea concentration higher (P0.001) than at the time of capture, while their blood glucose concentration exceeded (P0.01) that of farmed hinds. Hinds treated with Ascogen had lower ALT activity (P0.001) and showed a higher increase in PHA-induced blastogenic transformation of lymphocytes than the control hinds.

Changes in serum progesterone (P), oestrone (E1) and oestradiol (E2) concentrations were monitored in 34 female red deer (Cervus elaphus) shortly after the end of the breeding season and at mid-gestation. Pregnancy could be detected on the basis of serum P, but there were no significant differences between the pregnant and non-pregnant animals farmed animals in E1 and E2 concentrations. Twenty-five pregnant hinds captured in winter showed serum P levels similar to those found in farmed deer during the gestation period.

Steroid hormone determinations have been performed in amniotic fluid obtained by amniocentesis in 16 to 20 weeks of pregnancy utilizing our radioimmunological methods. Sporadic estimations reported in the literature were completed with our results of dehydroepiandrosterone (D) and dehydroepiandrosterone sulphate (DS) measurements obtained in relatively great number of cases. The observations allowed the early diagnosis of placental sulphatase deficiency. Study of this enzymopathy suggested that, in addition to oestrogens and progesterone, D and DS may have per se biological-hormonal effects for maturation processes in the intrauterine life. Furthermore, a hypothesis has been outlined for prenatal differential diagnostics of the congenital adrenal hyperplasia due to 3 beta-hydroxysteroid dehydrogenase deficiency.

Summary In winter wheat the physiological character of the photosynthesis taking place at high (20 °C) temperatures differs from that taking place at low (0 °C) temperatures. At low temperatures the P685 chlorophyll-a complex enables photosynthesis to occur, whereas at higher temperatures the active complex is P695. Under the influence of decreasing night temperature a rise in the level of P685 can be observed simultaneously with the gradual destruction of the P695 complex. At temperatures below the freezing point the P685 complex is still stable, whereas P695 is not. A definite relation exists between the phytochrome and the stability of the complexes at low temperature.

Summary Photochemical activities as a function of temperature have been compared in chloroplasts isoa ted from frost-resistant and frost-sensitive wheat cultivars. An Arrhenius plot of the activity of the Hill reaction by chloroplasts isolated from frost-resistant winter wheat shows a change in slope at about 10°C. Between 10 and 30 C the activation energy or this reaction is 4.2 kcal · mole − 1 . Between 5 and 0°C the activation energy decreases to − 12 kcal · mole − 1 whereas the Hill activity of chloroplasts of non frost-resistant plants shows a constant activation energy over the temperature range between 0 and 30°C. The activation energy was 4.2 kcal · mole − 1 . This value was similar to that observed for the frost-resistant plants at temperatures above 10°C. The decrease in activation energy observed in frost resistant winter wheat leaves at low temperatures was dependent on the stage of vernalization.

A gas chromatographic method has been employed for the determination of dehydroepiandrosterone (D), androsterone (A), dehydroepiandrosterone sulphate (DS) and androsterone sulphate (AS) in the peripheral blood of human subjects and in various mammals under physiological conditions and after the administration of D or DS. Unconjugated D has been isolated and the resting level determined in the rat, rabbit, dog, sheep, pig and cow, while DS was detectable in the peripheral circulation of the rat, dog and pig. Unconjugated A was present in blood of the rodents and domestic ungulates studied, while the parent sulphate could be demonstrated only in rat, dog, pig and cow. The plasma of lower mammals contained D in higher (0.8–10.9 μg/100 ml), and DS, if any, in lower level (1.5–5.7 μg/100 ml) than the human plasma samples (0.1–2.7 and 86–308 μg/100 ml, respectively). There was a more pronounced increase in D and A than in the DS and AS level in the rat and dog following administration of D. On the contrary, exogenous D hardly affected unconjugated D and appreciably enhanced the DS level in human plasma. The conclusion drawn for human subjects, that D is the metabolically active and DS the reserve hormone, does not seem to be valid for all the animals here studied.

Dehydroepiandrosterone (D) and dehydroepiandrosterone sulfate (DS) dynamics were studied in three obese female subjects following a single injection of [4-14C]D and [7α-3H]-DS tracers. Dynamic parameters were calculated simultaneously by both the urinary and blood method of compartmentalization. Estimates for the urinary secretion and production rates of D were found to be high, and those of DS varied within normal range. Calculation of the conversion factors, ρDDS and ρDSD, by the urinary method revealed a normal extra-glandular DS→ D conversion, while that for D → DS appeared deficient in obese female subjects. Estimates of inner and outer pool distribution volumes were extremely increased for free D; in contrast to this, moderately increased inner and decreased outer pool volumes of DS were observed. The metabolic clearance rates of D were normal or decreased and those for DS were greater than normal. The blood production rates of both D and DS were higher in obese female subjects than those estimated for normal women in our previous study.These observations suggest a considerable uptake of unconjugated D by adipose tissue, an overall poor D → DS conversion and an accelerated DS metabolism in obese female subjects.

The dynamic parameters of dehydroepiandrosterone and dehydroepiandrosterone sulphate metabolism have been determined following a single injection of [4-14C] dehydroepiandrosterone and [7α-3H] dehydroepiandrosterone sulphate into normal female subjects. The urinary secretion and production rates, the ϱDDS and ϱDSD conversion factors, the metabolic clearance rates, blood production rates and distribution volumes were calculated. Although the comparison between urinary and blood parameters of steroid dynamics suggested certain limitations of the methods used, they were found suitable for gaining information on dehydroepiandrosterone and dehydroepiandrosterone sulphate metabolism. A poor extra-adrenal conversion of dehydroepiandrosterone to the sulphate, small dehydroepiandrosterone sulphate and large dehydroepiandrosterone distribution volumes or clearance patterns, and a possible correlation between the blood parameters of dehydroepiandrosterone sulphate and anthropomorphology of normal female subjects were found.

Using radioimmunological methods, levels of cortisol, dehydroepiandrosterone, androstenedione, testosterone, oestrogens (oestradiol + oestrone), progesterone and 17 alpha-hydroxyprogesterone were determined in adipose tissue and peripheral blood obtained during surgical treatment of patients with non-endocrine diseases. The steroid content of human adipose tissue was observed to be extremely high relative to that in the general circulation, giving a tissue/serum ratio of 0.4 to 13.2. The concentration of steroids decreased in the following order: dehydroepiandrosterone greater than cortisol greater than androstenedione greater than progesterone greater than testosterone greater than 17 alpha-hydroxyprogesterone greater than oestradiol + oestrone. This sequence is different from that found in blood. When anthropometric variables were taken into consideration, the adipose tissue mass of severely obese subjects contained a steroid pool far greater than that in the total blood volume.

Single injections of ecdysone to newborn rats were followed by increases in the weights of the adrenals and decreases in the weights of the thymuses in the adults. No change was registered in body weights and in the weights of the gonads. The plasma androsterone levels seemed to decrease; however, the interindividual differences proved to be too great to draw definite conclusions.

An improved gas chromatographic method is reported for the determination of unconjugated and solvolysable dehydroepiandrosterone and androsterone in plasma. Free steroids below a level of 1 μg/100 cm3 are determined as heptafluorobutyrates by electron capture detection following extraction and thin-layer chromatographic purification. Free steroids above 1 μg/100 cm3 and steroid sulphates are measured as acetates using flame ionisation detection following solvolysis, extraction and thin-layer chromatography. Control experiments and representative normal values prove that the method is suitable for the determination of steroids in human, rat and dog plasma.

Twelve hypothyroid subjects, 13 healthy and 12 healthy women with a slight deficiency of vitamin D were studied to distinguish seasonal changes from the thyroxine-dependent ones. Serum 25-hydroxyvitamin D levels of hypothyroid patients were lower than those of healthy individuals when the sera were obtained in the autumn. In hypothyroid patients a single oral dose of 100 000 IU vitamin D3 resulted in a smaller increase in 25-hydroxyvitamin D concentration than in controls having subclinical exogenous vitamin D deficiency. Substitution therapy with thyroid hormone, started in our study always in autumn, increased the 25-hydroxyvitamin D concentration in hypothyroid patients, which was opposite to the autumn-to-spring variation of this hormone observed in healthy controls. The increase of 25-hydroxyvitamin D, dehydroepiandrosterone and its sulphate values following substitution therapy in the hypothyroid patients may indicate that thyroid hormone(s) is (are) involved in the regulation of steroid hormone synthesis.

Incubated rat adrenal slices failed to convert cholesterol, pregnenolone and 17-OH-progesterone into C19-steroids under the experimental conditions used. Dehydroepiandrosterone was converted to androstenedione and 11-OH-androstenedione. The formation of androstenedione and 11-OH-androstenedione could also be demonstrated by using testosterone precursor. Corticotrophin in vitro did not affect the rate of conversion and the amount of 11-hydroxylated derivative increased when ATP was also added to the medium. Human chorionic gonadotrophin enhanced 11-hydroxylation in the presence of ATP. Inhibition of 11β-hydroxylase activity by metopirone was not affected by ATP.