OJ287 is a quasi-periodic quasar with roughly 12 year optical cycles. It displays prominent outbursts that are predictable in a binary black hole model. The model predicted a major optical outburst in 2015 December. We found that the outburst did occur within the expected time range, peaking on 2015 December 5 at magnitude 12.9 in the optical R-band. Based on Swift/XRT satellite measurements and optical polarization data, we find that it included a major thermal component. Its timing provides an accurate estimate for the spin of the primary black hole, 0.313 0.01 c = . The present outburst also confirms the established general relativistic properties of the system such as the loss of orbital energy to gravitational radiation at the 2% accuracy level, and it opens up the possibility of testing the black hole no-hair theorem with 10% accuracy during the present decade.
Results from regular monitoring of relativistic compact binaries like PSR 1913+16 are consistent with the dominant (quadrupole) order emission of gravitational waves (GWs). We show that observations associated with the binary black hole (BBH) central engine of blazar OJ287 demand the inclusion of gravitational radiation reaction effects beyond the quadrupolar order. It turns out that even the effects of certain hereditary contributions to GW emission are required to predict impact flare timings of OJ287. We develop an approach that incorporates this effect into the BBH model for OJ287. This allows us to demonstrate an excellent agreement between the observed impact flare timings and those predicted from ten orbital cycles of the BBH central engine model. The deduced rate of orbital period decay is nine orders of magnitude higher than the observed rate in PSR 1913+16, demonstrating again the relativistic nature of OJ287ʼs central engine. Finally, we argue that precise timing of the predicted 2019 impact flare should allow a test of the celebrated black hole "no-hair theorem" at the 10% level.
PD-L1 protein expression was significantly higher in smoking-associated adenocarcinoma and in EGFR mutation-negative adenocarcinoma. PD-L1 protein expression was associated with poor survival in patients with lung adenocarcinoma. The PD-L1/programmed cell death 1 pathway may contribute to the progression of smoking-associated tumors in lung adenocarcinoma.
Abstract-Hepatocyte growth factor (HGF) is a potent angiogenic polypeptide that stimulates angiogenesis. Transcriptional regulation of HGF, however, has not been fully defined, with the exception of the hypoxia-mediated downregulation in cultured cells. In the present study, we report that angiogenic growth factors, including HGF, were upregulated in a murine model of critical limb ischemia in vivo, a finding that was in conflict with previous in vitro data. Mice deficient in basic fibroblast growth factor-2 (FGF-2) showed reduced induction of HGF protein in ischemic muscles, and overexpression of FGF-2 via gene transfer stimulated endogenous HGF, irrespective of the presence of ischemia. In culture, FGF-2 rapidly stimulated HGF mRNA, and a sustained expression was evident in the time course in vascular smooth muscle cells and fibroblasts. FGF-2-mediated induction of HGF was fully dependent on the mitogen-activated protein kinase pathway yet was not affected by either hypoxia or a protein kinase A inhibitor. In the early expression, FGF-2 directly stimulated HGF mRNA without the requirement of new protein synthesis, whereas sustained induction of HGF in the later phase was partly mediated by platelet-derived growth factor-AA. Furthermore, in vivo overexpression of FGF-2 significantly improved the blood perfusion, and the effect was abolished by systemic blockade of HGF in ischemic limbs. This is the first demonstration of a regulational mechanism of HGF expression via FGF-2 that was independent of the presence of hypoxia. The harmonized therapeutic effects of FGF-2, accompanied with the activity of endogenous HGF, may provide a beneficial effect for the treatment of limb ischemia.
Our data suggest that expression of PD-L1 protein is upregulated by the simultaneous amplification of the PD-L1 and JAK2 genes through JAK-STAT signaling in NCSLC.
Autophagy is a homeostatic mechanism that regulates protein and organelle turnover and uses the amino acids from degraded proteins to produce adenosine 5'-triphosphate (ATP). We investigated the activity of autophagy-associated pathways in liver regeneration after partial hepatectomy (PHx) in liver-specific autophagy-related gene 5 (Atg5) knockout (KO) mice. Liver regeneration was severely impaired by 70% PHx, with a reduction in postoperative mitosis, but a compensating increase in hepatocyte size. PHx induced intracellular adenosine triphosphate and b-oxidation reduction as well as injured cellular mitochondria. Furthermore, PHx in Atg5 KO mice enhanced hepatic accumulation of p62 and ubiquitinated proteins. These results indicated that reorganization of intracellular proteins and organelles during autophagy was impaired in the regenerating liver of these mice. Up-regulation of p21 was associated with hepatocyte senescence, senescence-associated b-galactosidase expression, irreversible growth arrest, and secretion of senescence-associated molecules, including interleukin (IL)-6 and IL-8. Conclusion: These findings indicate that autophagy plays a critical role in liver regeneration and in the preservation of cellular quality, preventing hepatocytes from becoming fully senescent and hypertrophic. (HEPATOLOGY 2014;60:290-300)
Rheumatoid arthritis (RA), a systemic inflammatory disease of unknown etiology, mainly affects synovial joints. Although angiogenic growth factors, including fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor (VEGF), may play a critical role in the development and progression of RA joint disease, little information is now available regarding their exact role in initiation and/or progression of RA. In this study, we show that both polypeptides were up-regulated in the rat joint synovial tissue of an adjuvant-induced model of arthritis (AIA), as well as human subjects with RA. FGF-2 overexpression via Sendai virus-mediated gene transfer significantly worsened clinical symptoms and signs of rat AIA, including hind paw swelling and radiological bone destruction, as well as histological findings based on inflammatory reaction, synovial angiogenesis, pannus formation, and osteocartilaginous destruction, associated with up-regulation of endogenous VEGF. FGF-2 gene transfer to non-AIA joints was without effect. These findings suggested that FGF-2 modulated disease progression, but did not affect initiation. Reverse experiments using anti-FGF-2-neutralizing rabbit IgG attenuated clinical symptoms and histopathological abnormalities of AIA joints. To our knowledge, this is the first report indicating direct in vivo evidence of disease-modulatory effects of FGF-2 in AIA, as probably associated with endogenous VEGF function. FGF-2 may prove to be a possible therapeutic target to treat subjects with RA.
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