363 research outputs found
Prudent banks and creative mimics : can we tell the difference?
The recent financial crisis has forced a rethink of banking
regulation and supervision and the role of financial innovation.
We develop a model where prudent banks may signal their type
through high capital ratios. Capital regulation may ensure separation
in equilibrium but deposit insurance will tend to increase
the level of capital required. If supervision detects risky behaviour
ex ante then it is complementary to capital regulation.
However, financial innovation may erode supervisors' ability to
detect risk and capital levels should then be higher. But regulators
may not be aware their capacities have been undermined.
We argue for a four-prong policy response with higher bank capital
ratios, enhanced supervision, limits to the use of complex
financial instruments and Coco's. Our results may support the
institutional arrangements proposed recently in the UK
Exploring the precision of femtosecond laser-assisted descemetorhexis in Descemet membrane endothelial keratoplasty
Objective Descemet membrane endothelial keratoplasty (DMEK) remains a challenging technique. We compare the precision of femtosecond laser-assisted DMEK to manual DMEK. Methods and Analysis A manual descemetorhexis (DR) of 8 mm diameter was compared with a femtosecond laser-assisted DR of the same diameter (femto-DR) in 22 pseudophakic patients requiring DMEK. We used OCT images with a centred xy-diagram to measure the postoperative precision of the DR and the amount of endothelial denuded area. Endothelial cell loss (ECL) and best corrected visual acuity were measured 3 months after surgery. Results In the manual group, the median error of the DR was 7% (range 3%-16%) in the x-diameter and 8% (range 2%-17%) in the y-diameter. In the femto group, the median error in the respective x and y-diameters was 1% (range 0.4%-3%) and 1% (range 0.006%-2.5%), smaller than in the manual group (p=0.001). Endothelial denuded areas were larger in the manual group (11.6 mm(2), range 7.6-18 mm(2)) than in the femto group (2.5 mm(2), range 1.25.9 mm(2)) (p<0.001). The ECL was 21% (range 5%-78%) in the manual DR and 17% (range 6%-38%) in the femto-DR group (p=0.351). The median visual acuity increased from 0.4 logMAR (range 0.6-0.4 logMAR) in both groups to 0.1 logMAR (range 0.4-0 logMAR) in the manual group and to 0.1 logMAR (range 0.3-0 logMAR) in the femto group (p=0.461). Three rebubblings were required in the manual group, whereas the femto group required only one. Conclusion The higher precision of the femto-DR bears the potential to improve DMEK surgery
Magnetic hybrid Pd/Fe-oxide nanoparticles meet the demands for ablative thermo-brachytherapy
Objective: To investigate the potential of hybrid Pd/Fe-oxide magnetic nanoparticles designed for thermo-brachytherapy of breast cancer, considering their specific loss power (SLP) and clinical constraints in the applied magnetic field. Methods: Hybrid nanoparticles consisting of palladium-core and iron oxide shell of increasing thickness, were suspended in water and their SLPs were measured at varying magnetic fields (12–26 mT peak) and frequencies (50–730 kHz) with a commercial alternating magnetic field generator (magneTherm™ Digital, nanoTherics Ltd.). Results: Validation of the heating device used in this study with commercial HyperMag-C nanoparticles showed a small deviation (±4%) over a period of 1 year, confirming the reliability of the method. The integration of dual thermometers, one in the center and one at the bottom of the sample vial, allowed monitoring of homogeneity of the sample suspensions. SLPs measurements on a series of nanoparticles of increasing sizes showed the highest heating for the diameter of 21 nm (SLP = 225 W/g) at the applied frequencies of 346 and 730 kHz. No heating was observed for the nanoparticles with the size <14 nm, confirming the importance of the size-parameter. The heating ability of the best performing Pd/Fe-oxide-21 was calculated to be sufficient to ablate tumors with a radius ±4 and 12 mm using 10 and 1 mg/mL nanoparticle concentration, respectively. Conclusions: Nanoparticles consisting of non-magnetic palladium-core and magnetic iron oxide shell are suitable for magnetic hyperthermia/thermal ablation under clinically safe conditions of 346 kHz and 19.1 mT, with minimal eddy current effects in combination with maximum SLP.</p
Magnetic hybrid Pd/Fe-oxide nanoparticles meet the demands for ablative thermo-brachytherapy
Objective: To investigate the potential of hybrid Pd/Fe-oxide magnetic nanoparticles designed for thermo-brachytherapy of breast cancer, considering their specific loss power (SLP) and clinical constraints in the applied magnetic field. Methods: Hybrid nanoparticles consisting of palladium-core and iron oxide shell of increasing thickness, were suspended in water and their SLPs were measured at varying magnetic fields (12–26 mT peak) and frequencies (50–730 kHz) with a commercial alternating magnetic field generator (magneTherm™ Digital, nanoTherics Ltd.). Results: Validation of the heating device used in this study with commercial HyperMag-C nanoparticles showed a small deviation (±4%) over a period of 1 year, confirming the reliability of the method. The integration of dual thermometers, one in the center and one at the bottom of the sample vial, allowed monitoring of homogeneity of the sample suspensions. SLPs measurements on a series of nanoparticles of increasing sizes showed the highest heating for the diameter of 21 nm (SLP = 225 W/g) at the applied frequencies of 346 and 730 kHz. No heating was observed for the nanoparticles with the size <14 nm, confirming the importance of the size-parameter. The heating ability of the best performing Pd/Fe-oxide-21 was calculated to be sufficient to ablate tumors with a radius ±4 and 12 mm using 10 and 1 mg/mL nanoparticle concentration, respectively. Conclusions: Nanoparticles consisting of non-magnetic palladium-core and magnetic iron oxide shell are suitable for magnetic hyperthermia/thermal ablation under clinically safe conditions of 346 kHz and 19.1 mT, with minimal eddy current effects in combination with maximum SLP.</p
Effects of TNFα receptor TNF-Rp55- or TNF-Rp75- deficiency on corneal neovascularization and lymphangiogenesis in the mouse
Tumor necrosis factor (TNF)α is an inflammatory cytokine likely to be involved in the process of corneal inflammation and neovascularization. In the present study we evaluate the role of the two receptors, TNF-receptor (TNF-R)p55 and TNF-Rp75, in the mouse model of suture-induced corneal neovascularization and lymphangiogenesis. Corneal neovascularization and lymphangiogenesis were induced by three 11–0 intrastromal corneal sutures in wild-type (WT) C57BL/6J mice and TNF-Rp55-deficient (TNF-Rp55d) and TNF-Rp75-deficient (TNF-Rp75d) mice. The mRNA expression of VEGF-A, VEGF-C, Lyve-1 and TNFα and its receptors was quantified by qPCR. The area covered with blood- or lymphatic vessels, respectively, was analyzed by immunohistochemistry of corneal flatmounts. Expression and localization of TNFα and its receptors was assessed by immunohistochemistry of sagittal sections and Western Blot. Both receptors are expressed in the murine cornea and are not differentially regulated by the genetic alteration. Both TNF-Rp55d and TNF-Rp75d mice showed a decrease in vascularized area compared to wild-type mice 14 days after suture treatment. After 21 days there were no differences detectable between the groups. The number of VEGF-A-expressing macrophages did not differ when comparing WT to TNF-Rp55d and TNF-Rp75d. The mRNA expression of lymphangiogenic markers VEGF-C or LYVE-1 does not increase after suture in all 3 groups and lymphangiogenesis showed a delayed effect only for TNF-Rp75d. TNFα mRNA and protein expression increased after suture treatment but showed no difference between the three groups. In the suture-induced mouse model, TNFα and its ligands TNF-Rp55 and TNF-Rp75 do not play a significant role in the pathogenesis of neovascularisation and lymphangiogenesis
Lack of netrin-4 modulates pathologic neovascularization in the eye
Netrins are a family of matrix-binding proteins that function as guidance
signals. Netrin-4 displays pathologic roles in tumorigenesis and
neovascularization. To answer the question whether netrin-4 acts either pro-
or anti-angiogenic, angiogenesis in the retina was assessed in Ntn-4−/− mice
with oxygen-induced retinopathy (OIR) and laser-induced choroidal
neovascularization (CNV), mimicking hypoxia-mediated neovascularization and
inflammatory mediated angiogenesis. The basement membrane protein netrin-4 was
found to be localised to mature retinal blood vessels. Netrin-4, but not
netrin-1 mRNA expression, increased in response to relative hypoxia and
recovered to normal levels at the end of blood vessel formation. No changes in
the retina were found in normoxic Ntn-4−/− mice. In OIR, Ntn-4−/− mice
initially displayed larger avascular areas which recovered faster to
revascularization. Ganzfeld electroretinography showed faster recovery of
retinal function in Ntn-4−/− mice. Expression of netrin receptors, Unc5H2
(Unc-5 homolog B, C. elegans) and DCC (deleted in colorectal carcinoma), was
found in Müller cells and astrocytes. Laser-induced neovascularization in
Nnt-4−/− mice did not differ to that in the controls. Our results indicate a
role for netrin-4 as an angiogenesis modulating factor in O2-dependent
vascular homeostasis while being less important during normal retinal
developmental angiogenesis or during inflammatory neovascularization
Lack of netrin-4 modulates pathologic neovascularization in the eye
Netrins are a family of matrix-binding proteins that function as guidance
signals. Netrin-4 displays pathologic roles in tumorigenesis and
neovascularization. To answer the question whether netrin-4 acts either pro-
or anti-angiogenic, angiogenesis in the retina was assessed in Ntn-4−/− mice
with oxygen-induced retinopathy (OIR) and laser-induced choroidal
neovascularization (CNV), mimicking hypoxia-mediated neovascularization and
inflammatory mediated angiogenesis. The basement membrane protein netrin-4 was
found to be localised to mature retinal blood vessels. Netrin-4, but not
netrin-1 mRNA expression, increased in response to relative hypoxia and
recovered to normal levels at the end of blood vessel formation. No changes in
the retina were found in normoxic Ntn-4−/− mice. In OIR, Ntn-4−/− mice
initially displayed larger avascular areas which recovered faster to
revascularization. Ganzfeld electroretinography showed faster recovery of
retinal function in Ntn-4−/− mice. Expression of netrin receptors, Unc5H2
(Unc-5 homolog B, C. elegans) and DCC (deleted in colorectal carcinoma), was
found in Müller cells and astrocytes. Laser-induced neovascularization in
Nnt-4−/− mice did not differ to that in the controls. Our results indicate a
role for netrin-4 as an angiogenesis modulating factor in O2-dependent
vascular homeostasis while being less important during normal retinal
developmental angiogenesis or during inflammatory neovascularization
Visual outcomes and complications following posterior iris-claw aphakic intraocular lens implantation combined with penetrating keratoplasty
Abstract Background To evaluate the indication, visual outcome, and complication rate after implantation of a posterior iris-claw aphakic intraocular lens (IOL) during penetrating keratoplasty. Methods This retrospective study comprised 23 eyes (23 patients) without adequate capsule support undergoing posterior iris-claw aphakic IOL implantation (Verisyse™/ Artisan®) during penetrating keratoplasty between 2005 and 2010. Mean follow-up was 18 months (range from 12 to 37 months). Results The IOLs were inserted during an IOL exchange in 17 eyes and as a secondary procedure in six aphakic eyes. Pseudophakic bullous keratopathy with corneal scar after anterior chamber intraocular lens (ACIOL) was the main indication for penetrating keratoplasty in 16 eyes (69.6 %). The final corrected distance visual acuity (CDVA) in logMAR (mean 1.0 ± 0.46) improved significantly (p < 0.05) compared to the preoperative CDVA (mean 1.8± 0.73). Twenty eyes (86.9 %) had a final visual acuity in logMAR better than the pre-operative CDVA. The mean postoperative IOP 16.3 mmHg±4.0 was not significantly (p > 0.05) higher compared to the preoperative IOP 15.6 mmHg±5.1. Complications included slight temporary pupil ovalization in three eyes (13.0 %) and iris-claw IOL sublocation in three eyes (13.0 %); all IOLs could be easily repositioned. Cystoid macular edema occured in one eye (4.3 %) 8 weeks after primary surgery. All grafts remained clear without any sign of graft rejection. Conclusions Retropupillar iris-claw IOL during penetrating keratoplasty provides good visual outcomes with a favorable complication rate, and can be used for a wide range of indications in eyes without adequate capsule support
The Nucleosome-Remodeling ATPase ISWI Is Regulated by Poly-ADP-Ribosylation
ATP-dependent nucleosome-remodeling enzymes and covalent modifiers of chromatin set the functional state of chromatin. However, how these enzymatic activities are coordinated in the nucleus is largely unknown. We found that the evolutionary conserved nucleosome-remodeling ATPase ISWI and the poly-ADP-ribose polymerase PARP genetically interact. We present evidence showing that ISWI is target of poly-ADP-ribosylation. Poly-ADP-ribosylation counteracts ISWI function in vitro and in vivo. Our work suggests that ISWI is a physiological target of PARP and that poly-ADP-ribosylation can be a new, important post-translational modification regulating the activity of ATP-dependent nucleosome remodelers
Genetic correlation between amyotrophic lateral sclerosis and schizophrenia
A. Palotie on työryhmän Schizophrenia Working Grp Psychiat jäsen.We have previously shown higher-than-expected rates of schizophrenia in relatives of patients with amyotrophic lateral sclerosis (ALS), suggesting an aetiological relationship between the diseases. Here, we investigate the genetic relationship between ALS and schizophrenia using genome-wide association study data from over 100,000 unique individuals. Using linkage disequilibrium score regression, we estimate the genetic correlation between ALS and schizophrenia to be 14.3% (7.05-21.6; P = 1 x 10(-4)) with schizophrenia polygenic risk scores explaining up to 0.12% of the variance in ALS (P = 8.4 x 10(-7)). A modest increase in comorbidity of ALS and schizophrenia is expected given these findings (odds ratio 1.08-1.26) but this would require very large studies to observe epidemiologically. We identify five potential novel ALS-associated loci using conditional false discovery rate analysis. It is likely that shared neurobiological mechanisms between these two disorders will engender novel hypotheses in future preclinical and clinical studies.Peer reviewe
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