70 research outputs found
The sustained post-outburst brightness of Nova Per 2018, the evolved companion, and the long orbital period
Nova Per 2018 (= V392 Per) halted the decline from maximum when it was 2mag
brighter than quiescence and since 2019 has been stable at such a plateau. The
ejecta have already fully diluted into the interstellar space. We obtained
BVRIgrizY photometry and optical spectroscopy of V392 Per during the plateau
phase and compared it with equivalent data gathered prior to the nova outburst.
We find the companion star to be a G9 IV/III and the orbital period to be
3.4118 days, making V392 Per the longest known period for a classical nova. The
location of V392 Per on the theoretical isochrones is intermediate between that
of classical novae and novae erupting within symbiotic binaries, in a sense
bridging the gap. The reddening is derived to be E(B-V)=0.72 and the fitting to
isochrones returns a 3.6 Gyr age for the system and 1.35 Msun, 5.3 Rsun, and 15
Lsun for the companion. The huge Ne overabundance in the ejecta and the very
fast decline from nova maximum both point to a massive white dwarf (M(WD) >=
1.1-1.2 Msun). The system is viewed close to pole-on conditions and the current
plateau phase is caused by irradiation of the CS by the WD still burning at the
surface.Comment: published in Astron.Astrophys. 639, L1
The cadaveric studies and the definition of the antero-lateral ligament of the knee: From the anatomical features to the patient-specific reconstruction surgical techniques
Cadaver studies represented a milestone in surgical orthopaedic research, and still today they play a crucial role in the achievement of new knowledge about joint disease behaviour and treatment. In this review, an overview of the cadaver studies available in the literature about the anatomy, role, and treatment of the antero-lateral ligament (ALL) of the knee was performed. The aim of the review was to describe and gain more insight into the part of in vitro study in understanding knee joint anatomy and biomechanics, and in developing surgical reconstruction techniques. The findings of the review showed that cadaver studies had, and will continue to have, a key role in the research of knee joint biomechanics and surgical reconstruction. Moreover, they represent a powerful tool to develop and test new devices which could be useful in clinical and surgical practice
Omi/HtrA2 promotes cell death by binding and degrading the anti-apoptotic protein ped/pea-15
ped/pea-15 is a ubiquitously expressed 15-kDa protein featuring a broad anti-apoptotic function. In a yeast two-hybrid screen, the pro-apoptotic Omi/HtrA2 mitochondrial serine protease was identified as a specific interactor of the ped/pea-15 death effector domain. Omi/HtrA2 also bound recombinant ped/pea-15 in vitro and co-precipitated with ped/pea-15 in 293 and HeLa cell extracts. In these cells, the binding of Omi/HtrA2 to ped/pea-15 was induced by UVC exposure and followed the mitochondrial release of Omi/HtrA2 into the cytoplasm. Upon UVC exposure, cellular ped/pea-15 protein expression levels decreased. This effect was prevented by the ucf-101 specific inhibitor of the Omi/HtrA2 proteolytic activity, in a dose-dependent fashion. In vitro incubation of ped/pea-15 with Omi/HtrA2 resulted in ped/pea-15 degradation. In intact cells, the inhibitory action of ped/pea-15 on UVC-induced apoptosis progressively declined at increasing Omi/HtrA2 expression. This further effect of Omi/HtrA2 was also inhibited by ucf-101. In addition, ped/pea-15 expression blocked Omi/HtrA2 co-precipitation with the caspase inhibitor protein XIAP and caspase 3 activation. Thus, in part, apoptosis following Omi/HtrA2 mitochondrial release is mediated by reduction in ped/pea-15 cellular levels. The ability of Omi/HtrA2 to relieve XIAP inhibition on caspases is modulated by the relative levels of Omi/HtrA2 and ped/pea-15
Omi/HtrA2 promotes cell death by binding and degrading the anti-apoptotic protein ped/pea-15
ped/pea-15 is a ubiquitously expressed 15-kDa protein featuring a broad anti-apoptotic function. In a yeast two-hybrid screen, the pro-apoptotic Omi/HtrA2 mitochondrial serine protease was identified as a specific interactor of the ped/pea-15 death effector domain. Omi/HtrA2 also bound recombinant ped/pea-15 in vitro and co-precipitated with ped/pea-15 in 293 and HeLa cell extracts. In these cells, the binding of Omi/HtrA2 to ped/pea-15 was induced by UVC exposure and followed the mitochondrial release of Omi/HtrA2 into the cytoplasm. Upon UVC exposure, cellular ped/pea-15 protein expression levels decreased. This effect was prevented by the ucf-101 specific inhibitor of the Omi/HtrA2 proteolytic activity, in a dose-dependent fashion. In vitro incubation of ped/pea-15 with Omi/HtrA2 resulted in ped/pea-15 degradation. In intact cells, the inhibitory action of ped/pea-15 on UVC-induced apoptosis progressively declined at increasing Omi/HtrA2 expression. This further effect of Omi/HtrA2 was also inhibited by ucf-101. In addition, ped/pea-15 expression blocked Omi/HtrA2 co-precipitation with the caspase inhibitor protein XIAP and caspase 3 activation. Thus, in part, apoptosis following Omi/HtrA2 mitochondrial release is mediated by reduction in ped/pea-15 cellular levels. The ability of Omi/HtrA2 to relieve XIAP inhibition on caspases is modulated by the relative levels of Omi/HtrA2 and ped/pea-15
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