711 research outputs found
Study of the cytological features of bone marrow mesenchymal stem cells from patients with neuromyelitis optica.
Neuromyelitis optica (NMO) is a refractory autoimmune inflammatory disease of the central nervous system without an effective cure. Autologous bone marrow‑derived mesenchymal stem cells (BM‑MSCs) are considered to be promising therapeutic agents for this disease due to their potential regenerative, immune regulatory and neurotrophic effects. However, little is known about the cytological features of BM‑MSCs from patients with NMO, which may influence any therapeutic effects. The present study aimed to compare the proliferation, differentiation and senescence of BM‑MSCs from patients with NMO with that of age‑ and sex‑matched healthy subjects. It was revealed that there were no significant differences in terms of cell morphology or differentiation capacities in the BM‑MSCs from the patients with NMO. However, in comparison with healthy controls, BM‑MSCs derived from the Patients with NMO exhibited a decreased proliferation rate, in addition to a decreased expression of several cell cycle‑promoting and proliferation‑associated genes. Furthermore, the cell death rate increased in BM‑MSCs from patients under normal culture conditions and an assessment of the gene expression profile further confirmed that the BM‑MSCs from patients with NMO were more vulnerable to senescence. Platelet‑derived growth factor (PDGF), as a major mitotic stimulatory factor for MSCs and a potent therapeutic cytokine in demyelinating disease, was able to overcome the decreased proliferation rate and increased senescence defects in BM‑MSCs from the patients with NMO. Taken together, the results from the present study have enabled the proposition of the possibility of combining the application of autologous BM‑MSCs and PDGF for refractory and severe patients with NMO in order to elicit improved therapeutic effects, or, at the least, to include PDGF as a necessary and standard growth factor in the current in vitro formula for the culture of NMO patient‑derived BM‑MSCs
N′-[(E)-2-Hydroxybenzylidene]-5-methylisoxazole-4-carbohydrazide monohydrate
In the structure of the title compound, C12H11N3O3·H2O, the dihedral angle formed by the benzene and isoxazole rings is 2.03 (8)°. The molecular conformation is stabilized by an intramolecular O—H⋯N hydrogen bond. In the crystal structure, molecules are linked into a three-dimesional network by intermolecular N—H⋯O, O—H⋯N and O—H⋯O hydrogen bonds, and by π–π stacking interactions involving adjacent benzene and isoxazole rings [centroid–centroid separation = 3.663 (2) Å]
Automatic Ship Detection of Remote Sensing Images from Google Earth in Complex Scenes Based on Multi-Scale Rotation Dense Feature Pyramid Networks
Ship detection has been playing a significant role in the field of remote
sensing for a long time but it is still full of challenges. The main
limitations of traditional ship detection methods usually lie in the complexity
of application scenarios, the difficulty of intensive object detection and the
redundancy of detection region. In order to solve such problems above, we
propose a framework called Rotation Dense Feature Pyramid Networks (R-DFPN)
which can effectively detect ship in different scenes including ocean and port.
Specifically, we put forward the Dense Feature Pyramid Network (DFPN), which is
aimed at solving the problem resulted from the narrow width of the ship.
Compared with previous multi-scale detectors such as Feature Pyramid Network
(FPN), DFPN builds the high-level semantic feature-maps for all scales by means
of dense connections, through which enhances the feature propagation and
encourages the feature reuse. Additionally, in the case of ship rotation and
dense arrangement, we design a rotation anchor strategy to predict the minimum
circumscribed rectangle of the object so as to reduce the redundant detection
region and improve the recall. Furthermore, we also propose multi-scale ROI
Align for the purpose of maintaining the completeness of semantic and spatial
information. Experiments based on remote sensing images from Google Earth for
ship detection show that our detection method based on R-DFPN representation
has a state-of-the-art performance.Comment: 14 pages, 11 figure
Cocoon-spinning behavior and 20-hydroxyecdysone regulation of fibroin genes in Plutella xylostella
The diamondback moth Plutella xylostella is a serious pest of crucifers. It has high reproductive potential and is resistant to many insecticides. Typically, the last-instar larvae of P. xylostella, before pupation, move to the lower or outer plant leaves to make a loose silk cocoon and pupate inside for adult formation. To better understand this pivotal stage we studied the cocoon-spinning behavior of P. xylostella and measured three successive phases by video-recording, namely the selection of a pupation site, spinning a loose cocoon and padding the scaffold cocoon. Subsequently, we cloned three fibroin genes related to cocoon production, i.e., fibroin light chain (Fib-L), fibroin heavy chain (Fib-H), and glycoprotein P25. A spatio-temporal study of these three fibroin genes confirmed a high expression in the silk glands during the final larval instar silk-producing stage. In parallel, we did an exogenous treatment of the insect molting hormone 20-hydroxyecdysone (20E), and this suppressed fibroin gene expression, reduced the normal time needed for cocoon spinning, and we also observed a looser cocoon structure under the scanning electron microscope. Hence, we demonstrated that the expression levels of key genes related to the synthesis of 20E [the three Halloween genes Spook (Spo), Shadow (Sad), and Shade (Shd)] decreased significantly during spinning, the expression of the 20E receptor (EcR and USP) was significantly lower during spinning than before spinning, and that the expression levels of CYP18-A1 related to 20E degradation were significantly up-regulated during spinning. The significance of the cocoon and the effects of 20E on the cocoon-spinning behavior of P. xylostella are discussed
Percutaneous closure of postinfarct muscular ventricular septal defects: A multicenter study in China
AbstractBackgroundSurgical repair is an effective method to treat ventricular septal defect (VSD) complicating acute myocardial infarction (AMI). However, the mortality rate remains high. This study was designed to assess the immediate and mid-term results of transcatheter closure of postinfarct muscular VSDs.MethodsData were retrospectively collected from 42 AMI patients who underwent attempted transcatheter VSD closure between 2008 and 2012 in seven heart centers of China.ResultsNine patients underwent emergent VSD closure in the acute phase (within two weeks from VSD) while the others underwent elective closure. The time between VSD occurrence and closure in emergency group and elective group was 7.7±2.3 days and 35±14.5 days, respectively (p<0.01). The percentage of procedure success in the emergency group and elective group was 77.8% (7/9) and 97% (32/33), respectively (p=0.048). The hospital mortality was higher for emergent closure in comparison to elective closure (66.7% vs. 6.1%, p<0.01). During a median follow-up of 25 months (0–58 months), two patients died at 8 and 29 months, respectively, and no serious complications occurred in other patients.ConclusionInterventional postinfarct VSD closure is a safe and effective approach that can be performed with a high procedural success rate, with favorable outcomes if it can be undertaken >14 days postinfarct
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