MicroRNAs (miRNAs) are a family of small non-coding RNA molecules of about 20-23 nucleotides in length, which negatively regulate protein-coding genes at post-transcriptional level. Using a stem-loop ...real-time-PCR method, we quantified the expression levels of 270 human miRNAs in 13 nasopharyngeal carcinoma (NPC) samples and 9 adjacent normal tissues, and identified 35 miRNAs whose expression levels were significantly altered in NPC samples. Several known oncogenic miRNAs, including miR-17-92 cluster and miR-155, are among the miRNAs upregulated in NPC. Tumour suppressive miRNAs, including miR-34 family, miR-143, and miR-145, are significantly downregulated in NPC. To explore the roles of these dysregulated miRNAs in the pathogenesis of NPC, a computational analysis was performed to predict the pathways collectively targeted by the 22 significantly downregulated miRNAs. Several biological pathways that are well characterised in cancer are significantly targeted by the downregulated miRNAs. These pathways include TGF-Wnt pathways, G1-S cell cycle progression, VEGF signalling pathway, apoptosis and survival pathways, and IP3 signalling pathways. Expression levels of several predicted target genes in G1-S progression and VEGF signalling pathways were elevated in NPC tissues and showed inverse correlation with the down-modulated miRNAs. These results indicate that these downregulated miRNAs coordinately regulate several oncogenic pathways in NPC.
High-energy photons from the Crab Nebula
The Crab Nebula contains a pulsar that excites the surrounding gas to emit high-energy radiation. The combination of the pulsar's youth and nearby location ...makes the nebula the brightest gamma-ray source in the sky. The LHAASO Collaboration report observations of this source at energies of tera– to peta–electron volts, extending the spectrum of this prototypical object. They combine these data with observations at lower energies to model the physics of the emission process. The multiwave-length data can be explained by a combination of synchrotron radiation and inverse Compton scattering.
Science
, abg5137, this issue p.
425
Detection of the Crab Nebula at peta–electron volt energies constrains the gamma-ray emission mechanism.
The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar’s rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10
−4
to 1.1 peta–electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta–electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron’s size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta–electron volt electrons, 2.5 × 10
36
ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta–electron volt protons to the production of the highest-energy gamma rays.
Both endoscopic obturation and transjugular intrahepatic portosystemic shunts (TIPSs) have proven to be effective in preventing rebleeding from gastric varices. This study compared the efficacy and ...complications of these modalities.
Cirrhotic patients with acute bleeding from gastric varices were considered for inclusion. After initial control, eligible patients were randomly allocated to two groups: TIPS (n = 35) and obturation using cyanoacrylate (n = 37). In the cyanoacrylate group, treatment was repeated regularly until gastric varices were obliterated. Patients of both groups received regular follow-up. The end points were gastric variceal rebleeding or death.
Stent shunt insertion was successful in all TIPS patients, and mean portal pressure gradient decreased from 21.4 +/- 7.5 mm Hg to 7.5 +/- 3.5 mm Hg ( P < 0.001). Variceal obliteration was achieved in 19 patients in the cyanoacrylate group (51 %) compared with seven TIPS patients (20 %) ( P < 0.02). After a median follow up of 33 months, upper gastrointestinal bleeding occurred in 15 TIPS patients (43 %) and 22 cyanoacrylate patients (59 %) ( P = 0.12). Rebleeding from gastric varices was encountered in four TIPS patients (11 %) and 14 cyanoacrylate patients (38 %) ( P = 0.014; odds ratio 3.6, 95 %CI 1.2 - 11.1). Blood transfusion requirements were lower in the TIPS group than in the cyanoacrylate group ( P < 0.01). Survival and frequency of complications were similar in both groups.
TIPS proved more effective than glue injection in preventing rebleeding from gastric varices, with similar survival and frequency of complications.
Water resources are essential to the ecosystem and social economy in the desert and oasis of the arid Tarim River basin, northwestern China, and expected to be vulnerable to climate change. It has ...been demonstrated that regional climate models (RCMs) provide more reliable results for a regional impact study of climate change (e.g., on water resources) than general circulation models (GCMs). However, due to their considerable bias it is still necessary to apply bias correction before they are used for water resources research. In this paper, after a sensitivity analysis on input meteorological variables based on the Sobol' method, we compared five precipitation correction methods and three temperature correction methods in downscaling RCM simulations applied over the Kaidu River basin, one of the headwaters of the Tarim River basin. Precipitation correction methods applied include linear scaling (LS), local intensity scaling (LOCI), power transformation (PT), distribution mapping (DM) and quantile mapping (QM), while temperature correction methods are LS, variance scaling (VARI) and DM. The corrected precipitation and temperature were compared to the observed meteorological data, prior to being used as meteorological inputs of a distributed hydrologic model to study their impacts on streamflow. The results show (1) streamflows are sensitive to precipitation, temperature and solar radiation but not to relative humidity and wind speed; (2) raw RCM simulations are heavily biased from observed meteorological data, and its use for streamflow simulations results in large biases from observed streamflow, and all bias correction methods effectively improved these simulations; (3) for precipitation, PT and QM methods performed equally best in correcting the frequency-based indices (e.g., standard deviation, percentile values) while the LOCI method performed best in terms of the time-series-based indices (e.g., Nash–Sutcliffe coefficient, R2); (4) for temperature, all correction methods performed equally well in correcting raw temperature; and (5) for simulated streamflow, precipitation correction methods have more significant influence than temperature correction methods and the performances of streamflow simulations are consistent with those of corrected precipitation; i.e., the PT and QM methods performed equally best in correcting flow duration curve and peak flow while the LOCI method performed best in terms of the time-series-based indices. The case study is for an arid area in China based on a specific RCM and hydrologic model, but the methodology and some results can be applied to other areas and models.
Abstract
The Cosmic Ray Energetics And Mass for the International Space Station (ISS-CREAM) experiment successfully recorded data for 539 days from 2017 August to 2019 February. We report the energy ...spectrum of cosmic-ray protons from the ISS-CREAM experiment at energies from 1.60 × 10
3
to 6.55 × 10
5
GeV. The measured spectrum deviates from a single power law. A smoothly broken power-law fit to the data, including statistical and systematic uncertainties, shows the spectral index change at 9.0 × 10
3
GeV from 2.57 ± 0.03 to 2.82 ± 0.02 with a significance of greater than 3
σ
. This bump-like structure is consistent with a spectral softening recently reported by the balloon-borne CREAM, DAMPE, and NUCLEON, but ISS-CREAM extends measurements to higher energies.
Purpose
To assess the efficacy and safety of drug-eluting beads transarterial chemoembolization (DEB-TACE) in liver cancer patients with different times of previous conventional transarterial ...chemoembolization (cTACE) treatments.
Methods
367 liver cancer patients about to receive DEB-TACE treatment were enrolled in this prospective cohort study. All patients were divided into no previous cTACE group (NPC group), 1–2 times previous cTACE group (PC group) and triple or above previous cTACE group (TPC group) according to the times of previous cTACE treatments.
Results
There was no difference in complete response (CR) (
P
= 0.671) and objective response rate (ORR) (
P
= 0.062) among three groups. Additionally, no difference in overall survival (OS) among groups (
P
= 0.899) was found. As to liver function, most liver function indexes were deteriorative at 1 week after DEB-TACE operation, but returned to baseline at 1–3 months after DEB-TACE operation in all three groups, while percentage of abnormal total bile acid (TBA) patients was higher in TPC group than NPC and PC groups at 1–3 month post-DEB-TACE (
P
= 0.018). As for safety profiles, the incidence of pain during DEB-TACE operation was lower in TPC group compared to NPC and PC groups (
P
= 0.005), while no difference of other adverse events was found during and 1 month post-DEB-TACE treatment among three groups.
Conclusion
DEB-TACE treatment was equally efficient and tolerated in liver cancer patients with different times of previous cTACE treatments.
Observational properties of throat aurora are investigated in detail by using 7 year continuous auroral observations obtained at Yellow River Station (magnetic latitude 76.24°N). From our inspection, ...throat aurora is often observed under the condition of stripy diffuse aurora contacting with the persistent discrete auroral oval, and the long‐period throat aurora observations generally consist of intermittent subsequences of throat aurora brightening followed by poleward moving auroral form and throat aurora dimming. We also noticed that the orientation of throat aurora is aligned along the ionospheric convection flow, and its local time distribution shows clear dependence on the interplanetary magnetic field (IMF) By component. These observational results indicate that factors inside the magnetosphere may play important role on occurrence of throat aurora. We thus suggest that throat aurora may present the ionospheric signature of redistribution of reconnection rate on the magnetopause by cold magnetospheric plasma flowing into the reconnection site. In addition, we also found that the occurrence rate of throat aurora clearly decreases with increase of the IMF cone angle (arccos(|Bx|/B)), which is very similar with the occurrence rate of high‐speed jet (HSJ) observed in magnetosheath depending on the IMF cone angle. This is suggested as that the HSJs occurred outside the magnetosphere may also play important role for generation of throat aurora by triggering magnetopause reconnection or by direct impacting. Although further studies are needed to clarify how the throat auroras are generated in detail, the relevant observations about throat aurora have presented important implications on a variety open questions, such as distribution and generation of cold plasma structures in the outer magnetosphere, magnetopause deformation, and possible relation between HSJ and reconnection.
Key Points
Throat aurora always observed together with diffuse aurora indicate that the occurrence is affected by factors inside the magnetosphere
Occurrence rate of throat aurora decreasing with increase of the IMF cone angle implies that the occurrence is affected by outside factors
Occurrence of throat aurora is related with factors both inside and outside the magnetosphere
The crystal structure and magnetoresponsive properties of Fe-doped MnCoGe alloys have been investigated using x-ray diffraction (XRD) and magnetic measurements. By alloying the Fe-containing ...isostructure compounds into MnCoGe, a magnetostructural transition from paramagnetic austenite to ferromagnetic martensite with large magnetization difference can be realized in a temperature window between the Curie temperatures of the austenite and martensite, resulting in a magnetic-field-induced martensitic transformation and large magnetic-entropy changes. A structural and magnetic phase diagram of Fe-doped MnCoGe alloys is presented.
► Isostructural alloying can manipulate structural stability of Fe-doped MnCoGe alloys. ► A magnetostructural transition was realized in a temperature window between TCA and TCM. ► The remarkable magnetoresponsive properties in Fe-doped MnCoGe alloys were found. ► A structural and magnetic phase diagram of Fe-doped MnCoGe alloys was proposed.
The transcription factors Runx2 and Osx are necessary for osteoblast and odontoblast differentiation, while Dspp is important for odontoblast differentiation. The relationship among Runx2, Osx, and ...Dspp during tooth and craniofacial bone development remains unknown. In this study, we hypothesized that the roles of Runx2 and Osx in the regulation of osteoblast and odontoblast lineages may be independent of one another. The results showed that Runx2 expression overlapped with Osx in dental and osteogenic mesenchyme from E12 to E16. At the later stages, from E18 to PN14, Runx2 and Osx expressions remained intense in alveolar bone osteoblasts. However, Runx2 expression was down-regulated, whereas Osx expression was clearly seen in odontoblasts. At later stages, Dspp transcription was weakly present in osteoblasts, but strong in odontoblasts where Osx was highly expressed. In mouse odontoblast-like cells, Osx overexpression increased Dspp transcription. Analysis of these data suggests differential biological functions of Runx2, Osx, and Dspp during odontogenesis and osteogenesis.
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