1,221 research outputs found
Transthyretin levels in the vitreous correlate with change in visual acuity after vitrectomy
Background/aim: Little is known about biochemical markers related to change in visual acuity after vitrectomy. The potential use of transthyretin (TTR), a carrier of the retinol/retinol-binding protein, as a biochemical marker protein, was investigated.
Methods: TTR was measured using immunonephelometry in a group of patients (n = 77) in longstanding (> 1 week) retinal detachment (n = 29), fresh (< 1 week) retinal detachment (n = 17), macular holes (n = 20) or diabetic retinopathy (n = 11). Vitreous samples were taken at the start of every vitrectomy procedure. For reference values, cadaver specimens (n = 73) were used.
Results: Reference values for vitreous TTR (median 18 mg/l; IQR 4 to 24 mg/l) comprised 2.2% of reference values for vitreous protein levels (median 538 mg/l; IQR 269 to 987 mg/l). Vitreous TTR values of patients were comparable in all disorders. Vitreous TTR values were higher in phakic (median 22.5 mg/l; IQR 10 to 27 mg/l) than in pseudophakic patients (median 12 mg/l; IQR 8 to 19 mg/l; p = 0.06). Postoperative change in visual acuity correlated well with vitreous TTR values found peroperatively (r(s) = 0.408; p = 0.012). Both change in visual acuity and lens status were the only variables which proved to explain the variance of TTR (multiple correlation coefficient: 0.494; phakic status: t = 2.767; p = 0.0084; and change in visual acuity t = 2.924: p = 0.0056).
Conclusion: Vitreous fluid concentrations of TTR can be regarded as a biochemical marker for retinal function
Trefoil peptides as proangiogenic factors in vivo and in vitro: implication of cyclooxygenase-2 and EGF receptor signaling
Effects of early versus delayed terlipressin infusion on hemodynamics and catecholamine requirements in ovine septic shock
Atomic self-interaction correction for molecules and solids
We present an atomic orbital based approximate scheme for self-interaction
correction (SIC) to the local density approximation of density functional
theory. The method, based on the idea of Filippetti and Spaldin [Phys. Rev. B
67, 125109 (2003)], is implemented in a code using localized numerical atomic
orbital basis sets and is now suitable for both molecules and extended solids.
After deriving the fundamental equations as a non-variational approximation of
the self-consistent SIC theory, we present results for a wide range of
molecules and insulators. In particular, we investigate the effect of
re-scaling the self-interaction correction and we establish a link with the
existing atomic-like corrective scheme LDA+U. We find that when no re-scaling
is applied, i.e. when we consider the entire atomic correction, the Kohn-Sham
HOMO eigenvalue is a rather good approximation to the experimental ionization
potential for molecules. Similarly the HOMO eigenvalues of negatively charged
molecules reproduce closely the molecular affinities. In contrast a re-scaling
of about 50% is necessary to reproduce insulator bandgaps in solids, which
otherwise are largely overestimated. The method therefore represents a
Kohn-Sham based single-particle theory and offers good prospects for
applications where the actual position of the Kohn-Sham eigenvalues is
important, such as quantum transport.Comment: 16 pages, 7 figure
Effects of short-term simultaneous infusion of dobutamine and terlipressin in patients with septic shock: the DOBUPRESS study
Background Terlipressin bolus infusion may reduce cardiac output and global oxygen supply. The present study was designed to determine whether dobutamine may counterbalance the terlipressin-induced depression in mixed-venous oxygen saturation (Svo2) in patients with catecholamine-dependent septic shock. Methods Prospective, randomized, controlled study performed in a university hospital intensive care unit. Septic shock patients requiring a continuous infusion of norepinephrine (0.9 µg kg−1 min−1) to maintain mean arterial pressure (MAP) at 70 (sd 5) mm Hg were randomly allocated to be treated either with (i) sole norepinephrine infusion (control, n=20), (ii) a single dose of terlipressin 1 mg (n=19), or (iii) a single dose of terlipressin 1 mg followed by dobutamine infusion titrated to reverse the anticipated reduction in Svo2 (n=20). Systemic, pulmonary, and regional haemodynamic variables were obtained at baseline and after 2 and 4 h. Laboratory surrogate markers of organ (dys)function were tested at baseline and after 12 and 24 h. Results Terlipressin (with and without dobutamine) infusion preserved MAP at 70 (5) mm Hg, while allowing to reduce norepinephrine requirements to 0.17 (0.2) and 0.2 (0.2) µg kg−1 min−1, respectively [vs1.4 (0.3) µg kg−1 min−1 in controls at 4 h; each P<0.001]. The terlipressin-linked decrease in Svo2 was reversed by dobutamine at a mean dose of 20 (8) µg kg−1 min−1 [Svo2 at 4 h: 59 (11)% vs 69 (12)%, P=0.028]. Conclusions In human catecholamine-dependent septic shock, terlipressin (with and without concomitant dobutamine infusion) increases MAP and markedly reduces norepinephrine requirements. Although no adverse events were noticed in the present study, potential benefits of increasing Svo2 after terlipressin bolus infusion need to be weighted against the risk of cardiovascular complications resulting from high-dose dobutamin
МНОГОФАЗНО-ОДНОФАЗНыЕ РЕВЕРСИВНыЕ ЭЛЕКТРОМАШИННО-ВЕНТИЛЬНыЕ ПРЕОБРАЗОВАТЕЛИ БЕСКОНТАКТНыХ МАШИН ДВОЙНОГО ПИТАНИЯ
Розглянуто процеси в багатофазно-однофазних реверсивних електромашинно-вентильних перетворю-
вачах безконтактних машин подвійного живлення.
Рассмотрены процессы в многофазно-однофазных реверсивных электромашинно-вентильных преобра-
зователях бесконтактных машин двойного питания
Impact of saline-based tetrastarch vs balanced tetrastarch and crystalloid solutions on hyperchloraemic acidosis in endotoxaemic sheep
Evidence for orbital ordering in LaCoO3
We present powder and single crystal X-ray diffraction data as evidence for a
monoclinic distortion in the low spin (S=0) and intermediate spin state (S=1)
of LaCoO3. The alternation of short and long bonds in the ab plane indicates
the presence of eg orbital ordering induced by a cooperative Jahn-Teller
distortion. We observe an increase of the Jahn-Teller distortion with
temperature in agreement with a thermally activated behavior of the Co3+ ions
from a low-spin ground state to an intermediate-spin excited state.Comment: Accepted to Phys. Rev.
Long-range charge density wave proximity effect at cuprate-manganate interfaces
The interplay between charge density waves (CDWs) and high-temperature
superconductivity is currently under intense investigation. Experimental
research on this issue is difficult because CDW formation in bulk copper-oxides
is strongly influenced by random disorder, and a long-range-ordered CDW state
in high magnetic fields is difficult to access with spectroscopic and
diffraction probes. Here we use resonant x-ray scattering in zero magnetic
field to show that interfaces with the metallic ferromagnet
LaCaMnO greatly enhance CDW formation in the optimally
doped high-temperature superconductor YBaCuO (), and that this effect persists over several tens of nm. The wavevector
of the incommensurate CDW serves as an internal calibration standard of the
charge carrier concentration, which allows us to rule out any significant
influence of oxygen non-stoichiometry, and to attribute the observed phenomenon
to a genuine electronic proximity effect. Long-range proximity effects induced
by heterointerfaces thus offer a powerful method to stabilize the charge
density wave state in the cuprates, and more generally, to manipulate the
interplay between different collective phenomena in metal oxides.Comment: modified version published in Nature Material
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