506 research outputs found
4,6-Dimethylpyrimidin-2(1H)-one–urea–water (1/1/1)
In the crystal structure of the title compound, C6H8N2O·CH4N2O·H2O, molecules are linked via N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds, forming a three–dimensional framework
A moderate spin for the black hole in X-ray binary MAXI J1348-630 revealed by Insight-HXMT
MAXI J1348-630 is a low-mass X-ray black hole binary located in the Galaxy
and undergone the X-ray outburst in 2019. We analyzed the observation data in
very soft state during the outburst between MJD 58588 and MJD 58596 based on
the Insight-HXMT observations from 2 -- 20 keV via the continuum fitting method
to measure the spin of the stellar-mass black hole in MAXI J1348-630. The inner
disk temperature and the apparent inner disk radius were found to be and from the observation data modeled by
the multicolor disc blackbody model. Assuming the distance of the source , the mass of the black hole , and the
inclination of the system , the spin is determined to be
for fixing hardening factor at 1.6 and
. Besides, considering the uncertainty of
the parameters of this system, with the Monte Carlo analysis, we
still confirm the moderate spin of the black hole as
. Some spectral parameters (e.g., column
density and hardening factor) which could affect the measurements of the BH
spin are also briefly discussed.Comment: 10 pages, 14 figures, 5 tables, accept for publication in MNRA
1,1′-(Butane-1,4-diyl)dipyridinium dibromide dihydrate
The organic cation in the title compound, C14H18N2
2+·2Br−·2H2O, is situated on an inversion centre. The cations, anions and water molecules are linked via O—H⋯Br, C—H⋯Br and C—H⋯O hydrogen bonds, and π–π stacking interactions between adjacent pyridine rings, with a centroid–centroid separation of 3.8518 (17) Å
Overproduction of Mitochondrial Fission Proteins in Membranous Nephropathy in Children
Background/Aims: The molecules involved in nephrotic syndrome (NS) have not been fully clarified. Mitochondrial fission proteins are found to be involved in podocyte injury in vitro. Increased glomerular expression of mitochondrial fission proteins was found in adriamycin nephropathy in our previous study. Whether or not mitochondrial fission proteins are involved in podocyte injury in NS is not clear. This study explored the glomerular expression and possible pathological significance of mitochondrial fission-associated proteins, including dynamin-related protein 1 (Drp1) and mitochondrial fission protein 1 (Fis1), in children with NS. Methods: Eighteen children with primary NS, including 6 with minimal change disease, 6 with focal segmental glomerulosclerosis, 6 with membranous nephropathy, 6 children with isolated haematuria and 3 normal controls were included. The glomerular expression of Drp1, phospho-Drp1 (Ser616) and Fis1, urinary protein measurements, and podocyte mitochondrial density under electron microscopy were investigated and compared. Results: Glomerular expression of Drp1, phospho-Drp1 (Ser616) and Fis1 was mainly increased in children with NS with membranous nephropathy. No relationship was found between glomerular expression of Drp1, phospho-Drp1 (Ser616) and Fis1 and podocyte mitochondrial density or urinary protein measurements. Conclusion: Glomerular overproduction of Drp1, phospho-Drp1 (Ser 616) and Fis1 occurred mainly in children with membranous nephropathy. The pathological significance deserves further investigation
Sub-second periodic radio oscillations in a microquasar
Powerful relativistic jets are one of the ubiquitous features of accreting
black holes in all scales. GRS 1915+105 is a well-known fast-spinning
black-hole X-ray binary with a relativistic jet, termed as a ``microquasar'',
as indicated by its superluminal motion of radio emission. It exhibits
persistent x-ray activity over the last 30 years, with quasi-periodic
oscillations of Hz and 34 and 67 Hz in the x-ray band. These
oscillations likely originate in the inner accretion disk, but other origins
have been considered. Radio observations found variable light curves with
quasi-periodic flares or oscillations with periods of minutes.
Here we report two instances of 5 Hz transient periodic oscillation
features from the source detected in the 1.05-1.45 GHz radio band that occurred
in January 2021 and June 2022, respectively. Circular polarization was also
observed during the oscillation phase.Comment: The author version of the article which will appear in Nature on 26
July 2023, 32 pages including the extended data. The online publication
version can be found at the following URL:
https://www.nature.com/articles/s41586-023-06336-
A proposed disease classification system for duck viral hepatitis
The nomenclature of duck viral hepatitis (DVH) was historically not a problem. However, 14 hepatotropic viruses among 10 different genera are associated with the same disease name, DVH. Therefore, the disease name increasingly lacks clarity and may no longer fit the scientific description of the disease. Because one disease should not be attributed to 10 genera of viruses, this almost certainly causes misunderstanding regarding the disease-virus relationship. Herein, we revisited the problem and proposed an update to DVH disease classification. This classification is based on the nomenclature of human viral hepatitis and the key principle of Koch's postulates (“one microbe and one disease”). In total, 10 types of disease names have been proposed. These names were literately matched with hepatitis-related viruses. We envision that this intuitive nomenclature system will facilitate scientific communication and consistent interpretation in this field, especially in the Asian veterinary community, where these diseases are most commonly reported
Synergy between Proteasome Inhibitors and Imatinib Mesylate in Chronic Myeloid Leukemia
Resistance developed by leukemic cells, unsatisfactory efficacy on patients with chronic myeloid leukemia (CML) at accelerated and blastic phases, and potential cardiotoxity, have been limitations for imatinib mesylate (IM) in treating CML. Whether low dose IM in combination with agents of distinct but related mechanisms could be one of the strategies to overcome these concerns warrants careful investigation.We tested the therapeutic efficacies as well as adverse effects of low dose IM in combination with proteasome inhibitor, Bortezomib (BOR) or proteasome inhibitor I (PSI), in two CML murine models, and investigated possible mechanisms of action on CML cells. Our results demonstrated that low dose IM in combination with BOR exerted satisfactory efficacy in prolongation of life span and inhibition of tumor growth in mice, and did not cause cardiotoxicity or body weight loss. Consistently, BOR and PSI enhanced IM-induced inhibition of long-term clonogenic activity and short-term cell growth of CML stem/progenitor cells, and potentiated IM-caused inhibition of proliferation and induction of apoptosis of BCR-ABL+ cells. IM/BOR and IM/PSI inhibited Bcl-2, increased cytoplasmic cytochrome C, and activated caspases. While exerting suppressive effects on BCR-ABL, E2F1, and β-catenin, IM/BOR and IM/PSI inhibited proteasomal degradation of protein phosphatase 2A (PP2A), leading to a re-activation of this important negative regulator of BCR-ABL. In addition, both combination therapties inhibited Bruton's tyrosine kinase via suppression of NFκB.These data suggest that combined use of tyrosine kinase inhibitor and proteasome inhibitor might be helpful for optimizing CML treatment
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