Circulating Irisin Levels Are Not Affected by Coffee Intake: A Randomized Controlled Trial

Irisin, secreted by skeletal muscle and possibly fat, is hypothesized to play an important role in modulating energy expenditure, obesity and metabolism. Coffee consumption also increases energy expenditure and leads to positive metabolic effects, but whether these effects are mediated by irisin remains unknown. The objective of this study was to determine the association between baseline irisin levels and the metabolic profile in humans and to investigate whether consumption of caffeinated coffee alters irisin levels. To this end, a secondary analysis was performed investigating irisin levels at baseline and after eight weeks in 32 healthy, overweight coffee drinkers who were randomized to consumption of 5 cups per day of instant caffeinated coffee, decaffeinated coffee, or water. Spearman correlation and analysis of covariance analyses were performed to identify possible associations. Irisin levels were positively correlated with waist circumference (r = 0.41, p = 0.02), fat mass (r = 0.44, p = 0.01) and CRP (r = 0.47, p = 0.007). Though there was a trend towards increased levels of irisin over time in the caffeinated coffee group (+1.8%) when compared to the placebo group (−4%) this did not reach statistical significance (p = 0.75 for the trend). This first randomized trial failed to reveal any effects of coffee consumption on irisin levels, but a larger trial, appropriately sized on the basis of data provided by this study, is needed to conclusively investigate such a relationship. Trial Registration Clinicaltrials.gov NCT0030509

Bilateral herpetic keratitis presenting with unilateral neurotrophic keratitis in pemphigus foliaceus: a case report

<p>Abstract</p> <p>Introduction</p> <p>We report a case of bilateral herpetic keratitis developing after rapid oral corticosteroid tapering in a patient with pemphigus foliaceus, which was followed by unilateral neurotrophic keratitis that was treated with amniotic membrane transplantation.</p> <p>Case presentation</p> <p>A 71-year-old Korean man developed bilateral herpetic keratitis one week after rapid tapering of systemic corticosteroid. He had been on high-dose oral corticosteroid and azathioprine therapy for six months for treatment of pemphigus foliaceus. Topical acyclovir ointment was prescribed. A week later, our patient's right eye had healed, but his left eye showed increased stromal edema with enlarged epithelial defects. He was prescribed oral acyclovir with topical broad-spectrum antibiotics applied to his left eye. The stromal edema cleared within a week but the epithelial defect remained unchanged. An amniotic membrane transplantation was performed on our patient's left eye, and his epithelial defect had totally healed three weeks later.</p> <p>Conclusions</p> <p>Patients with autoimmune disease or who are on immunosuppressive therapy have a higher chance of developing bilateral herpetic keratitis. Although rare, the condition may be followed by unilateral neurotrophic keratitis. Rapid corticosteroid tapering may act as a triggering factor for viral infection or reactivation of herpes.</p

Dependence of reaction center-type energy-dependent quenching on photosystem II antenna size

AbstractThe effects of photosystem II antenna size on reaction center-type energy-dependent quenching (qE) were examined in rice plants grown under two different light intensities using both wild type and qE-less (OsPsbS knockout) mutant plants. Reaction center-type qE was detected by measuring non-photochemical quenching at 50 μmol photons m−2 s−1 white light intensity. We observed that in low light-grown rice plants, reaction center-type qE was higher than in high light-grown plants, and the amount of reaction center-type qE did not depend on zeaxanthin accumulation. This was confirmed in Arabidopsis npq1–2 mutant plants that lack zeaxanthin due to a mutation in the violaxanthin de-epoxidase enzyme. Although the electron transport rate measured at a light intensity of 50 μmol photons m−2 s−1 was the same in high light- and low light-grown wild type and mutant plants lacking PsbS protein, the generation of energy-dependent quenching was completely impaired only in mutant plants. Analyses of the pigment content, Lhcb proteins and D1 protein of PSII showed that the antenna size was larger in low light-grown plants, and this correlated with the amount of reaction center-type qE. Our results mark the first time that the reaction center-type qE has been shown to depend on photosystem II antenna size and, although it depends on the existence of PsbS protein, the extent of reaction center-type qE does not correlate with the transcript levels of PsbS protein. The presence of reaction center-type energy-dependent quenching, in addition to antenna-type quenching, in higher plants for dissipation of excess light energy demonstrates the complexity and flexibility of the photosynthetic apparatus of higher plants to respond to different environmental conditions

Contractile force is enhanced in Aortas from pendrin null mice due to stimulation of angiotensin II-dependent signaling.

Pendrin is a Cl-/HCO3- exchanger expressed in the apical regions of renal intercalated cells. Following pendrin gene ablation, blood pressure falls, in part, from reduced renal NaCl absorption. We asked if pendrin is expressed in vascular tissue and if the lower blood pressure observed in pendrin null mice is accompanied by reduced vascular reactivity. Thus, the contractile responses to KCl and phenylephrine (PE) were examined in isometrically mounted thoracic aortas from wild-type and pendrin null mice. Although pendrin expression was not detected in the aorta, pendrin gene ablation changed contractile protein abundance and increased the maximal contractile response to PE when normalized to cross sectional area (CSA). However, the contractile sensitivity to this agent was unchanged. The increase in contractile force/cross sectional area observed in pendrin null mice was due to reduced cross sectional area of the aorta and not from increased contractile force per vessel. The pendrin-dependent increase in maximal contractile response was endothelium- and nitric oxide-independent and did not occur from changes in Ca2+ sensitivity or chronic changes in catecholamine production. However, application of 100 nM angiotensin II increased force/CSA more in aortas from pendrin null than from wild type mice. Moreover, angiotensin type 1 receptor inhibitor (candesartan) treatment in vivo eliminated the pendrin-dependent changes contractile protein abundance and changes in the contractile force/cross sectional area in response to PE. In conclusion, pendrin gene ablation increases aorta contractile force per cross sectional area in response to angiotensin II and PE due to stimulation of angiotensin type 1 receptor-dependent signaling. The angiotensin type 1 receptor-dependent increase in vascular reactivity may mitigate the fall in blood pressure observed with pendrin gene ablation

Exact soluble two-dimensional charged wormhole

We present an exactly soluble charged wormhole model in two dimensions by adding infalling chiral fermions on the static wormhole. The infalling energy due to the infalling charged matter requires the classical back reaction of the geometry, which is solved by taking into account of the nontrivial nonchiral exotic energy. Finally, we obtain the exact expression for the size of the throat depending on the total amount of the infalling net energy and discuss the interesting transition from the AdS spacetime to the wormhole geometry.Comment: 8 pages, no figure

An improved baculovirus insecticide producing occlusion bodies that contain Bacillus thuringiensis insect toxin

Baculovirus occlusion bodies, large proteinaceous structures which contain virions, have recently been engineered to incorporate foreign proteins. The major constituent protein of occlusion bodies from the baculovirus Autographa californica nucleopolyhedrovirus is polyhedrin, and assembly of recombinant occlusion bodies which incorporate a foreign protein depends on an interaction between native polyhedrin and a polyhedrin–foreign protein fusion. This technology has now been applied to the generation of a recombinant baculovirus (ColorBtrus) that produces occlusion bodies incorporating the Bacillus thuringiensis (Bt) insecticidal Cry1Ac toxin protein. ColorBtrus coexpresses native polyhedrin and a fusion protein in which polyhedrin is fused to the Bt toxin, which is in turn fused to green fluorescent protein (GFP). Analysis of ColorBtrus occlusion bodies confirmed that they include both Bt toxin and GFP, yet still incorporate virions. Bioassay of ColorBtrus demonstrated that its speed of action and pathogenicity are strikingly enhanced compared to wild-type virus. ColorBtrus represents a novel, powerful biological insecticide that combines positive attributes of both Bt toxin and baculovirus based systems

Raman Scattered He II λ\lambda 6545 Line in the Symbiotic Star V1016 Cygni

We present a spectrum of the symbiotic star V1016 Cyg observed with the 3.6 m Canada-France-Hawaii Telescope, in order to illustrate a method to measure the covering factor of the neutral scattering region around the giant component with respect to the hot emission region around the white dwarf component. In the spectrum, we find broad wings around H$\alpha$ and a broad emission feature around 6545${\rm \AA}$ that is blended with the [N II]$\lambda$ 6548 line. These two features are proposed to be formed by Raman scattering by atomic hydrogen, where the incident radiation is proposed to be UV continuum radiation around Ly$\beta$ in the former case and He II $\lambda$ 1025 emission line arising from $n=6\to n=2$ transitions for the latter feature. We remove the H$\alpha$ wings by a template Raman scattering wing profile and subtract the [N II] $\lambda$ 6548 line using the 3 times stronger [N II] $\lambda$ 6583 feature in order to isolate the He II Raman scattered 6545 \AA line. We obtain the flux ratio $F_{6545}/F_{6560}=0.24$ of the He II $\lambda$ 6560 emission line and the 6545 \AA feature for V1016 Cyg. Under the assumption that the He II emission from this object is isotropic, this ratio is converted to the ratio $\Phi_{6545}/\Phi_{1025}=0.17$ of the number of the incident photons and that of the scattered photons. This implies that the scattering region with H I column density $N_{HI}\ge 10^{20}{\rm cm^{-2}}$ covers 17 per cent of the emission region. By combining the presumed binary period $\sim 100$ yrs of this system we infer that a significant fraction of the slow stellar wind from the Mira component is ionized and that the scattering region around the Mira extends a few tens of AU, which is closely associated with the mass loss process of the Mira component.Comment: 12 pages, 6 figures, accepted for publication in Ap

Nanomechanical Contribution of Collagen and von Willebrand Factor A in Marine Underwater Adhesion and Its Implication for Collagen Manipulation

Recent works on mussel adhesion have identified a load bearing matrix protein (PTMP1) containing von Willebrand factor (vWF) with collagen binding capability that contributes to the mussel holdfast by manipulating mussel collagens. Using a surface forces apparatus, we investigate for the first time, the nanomechanical properties of vWF-collagen interaction using homologous proteins of mussel byssus, PTMP1 and preCollagens (preCols), as collagen. Mimicking conditions similar to mussel byssus secretion (pH < 5.0) and seawater condition (pH 8.0), PTMP1 and preCol interact weakly in the "positioning" phase based on vWF-collagen binding and strengthen in "locked" phase due to the combined effects of electrostatic attraction, metal binding, and mechanical shearing. The progressive enhancement of binding between PTMP1 with porcine collagen under the aforementioned conditions is also observed. The binding mechanisms of PTMP1-preCols provide insights into the molecular interaction of the mammalian collagen system and the development of an artificial extracellular matrix based on collagens.1142sciescopu