Rituximab has been associated with hepatitis B virus reactivation (HBV-R). However, the characteristics and scope of this association remain largely undefined.
We completed a comprehensive literature ...search of all published rituximab-associated HBV-R cases and from the Food and Drug Administration (FDA) Adverse Event Reporting System (AERS) MedWatch database. Literature and FDA cases were compared for completeness, and a meta-analysis was completed.
One hundred and eighty-three unique cases of rituximab-associated HBV-R were identified from the literature (n = 27 case reports, n = 156 case series). The time from last rituximab to reactivation was 3 months (range 0–12), although 29% occurred >6 months after last rituximab. Within FDA data (n = 118 cases), there was a strong signal for rituximab-associated HBV-R proportional reporting ratio = 28.5, 95% confidence interval (CI) 23.9–34.1; Empiric Bayes Geometric Mean = 26.4, 95% CI 21.4–31.1. However, the completeness of data in FDA reports was significantly inferior compared with literature cases (P < 0.0001). Among HBV core antibody (HBcAb(+)) series, the pooled effect of rituximab-based therapy showed a significantly increased risk of HBV-R compared with nonrituximab-treated patients (odds ratio 5.73, 95% CI 2.01–16.33; Z = 3.33, P = 0.0009) without heterogeneity (χ2 = 2.12, P = 0.5473).
The FDA AERS provided strong HBV-R safety signals; however, literature-based cases provided a significantly more complete description. Furthermore, meta-analysis of HBcAb(+) series identified a more than fivefold increased rate of rituximab-associated HBV-R.
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.
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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.
Background
Enucleation of pancreatic neuroendocrine tumours (pNETs) via robotic surgery has rarely been described. This study sought to assess the safety and efficiency of robotic surgery for the ...enucleation of small pNETs.
Methods
A comparison was conducted of enucleation of pNETs smaller than 2 cm by robotic or open surgery between January 2000 and May 2015. Propensity score matching was used to balance sex, age, BMI, tumour location and tumour diameter. Pathological results, safety‐related outcomes (postoperative pancreatic fistula (POPF) rate, estimated blood loss, and short‐term mortality and morbidity) and efficiency‐related outcomes (duration of surgery and postoperative length of hospital stay) were compared between the groups.
Results
A cohort of 120 patients with pNET were enrolled in the study (1 : 1 matched for open or robotic surgery, 60 per group). Ninety‐three patients (77·5 per cent) had a grade 1 tumour and 114 (95·0 per cent) had an insulinoma. Robotic surgery had a conversion rate of 5 per cent (3 of 60), and was not associated with an increased POPF rate (10 per cent versus 17 per cent after open surgery; P = 0·283) or grade III–V surgical complications according to the Dindo–Clavien classification (3 versus 10 per cent respectively; P = 0·272). Estimated blood loss was reduced with the robotic approach (32·5 versus 80·0 ml in the open group; P = 0·008), as was duration of surgery (117 versus 150 min; P < 0·001). Length of hospital stay after surgery was similar in the two groups (12·0 versus 13·5 days respectively; P = 0·071).
Conclusion
Robotic surgery for enucleation of pNETs smaller than 2 cm did not increase POPF or major complication rates, and reduced the duration of surgery and estimated blood loss, compared with open surgery. Registration number: NCT02125929 (
https://www.clinicaltrials.gov/).
Robot beats surgeon
An outstanding goal in quantum optics and scalable photonic quantum technology is to develop a source that each time emits one and only one entangled photon pair with simultaneously high entanglement ...fidelity, extraction efficiency, and photon indistinguishability. By coherent two-photon excitation of a single InGaAs quantum dot coupled to a circular Bragg grating bull's-eye cavity with a broadband high Purcell factor of up to 11.3, we generate entangled photon pairs with a state fidelity of 0.90(1), pair generation rate of 0.59(1), pair extraction efficiency of 0.62(6), and photon indistinguishability of 0.90(1) simultaneously. Our work will open up many applications in high-efficiency multiphoton experiments and solid-state quantum repeaters.
The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 10
electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV ...energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays
. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref.
). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane
, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.
To sufficiently store and use high-quality heat energy, thermal stratification is gradually applied in many kinds of energy storage fields such as solar thermal utilization system. Because of the ...unsteady characteristics of solar radiation, thermal storage becomes very essential in long-term operation of heating load. The wide application of thermal stratification lies in the minimization of the mixing effect by use of the thermal stratification, which is caused by the thermal buoyancy because of the difference of temperature between cold and hot water. According to the review, the conception of thermal stratification allows a wide variety of different design embodiments, which essentially extends the fields of practical application of these devices. In this paper a survey of the various types of thermal stratification tanks and research methods is presented, and reasons of energy storage with efficiency problems related to the applications are introduced and benefits offered by thermal stratification are outlined. The structure designs based on theoretical prediction of thermal-stratified water tank performed at many organizations are introduced and are compared with their experimental results. Finally, the development of the tank with thermal stratification in the future application is predicted.
We investigate polarization-dependent ultrafast photocurrents in the Weyl semimetal TaAs using terahertz (THz) emission spectroscopy. Our results reveal that highly directional, transient ...photocurrents are generated along the noncentrosymmetric c axis regardless of incident light polarization, while helicity-dependent photocurrents are excited within the ab plane. This is consistent with earlier static photocurrent experiments, and demonstrates on the basis of both the physical constraints imposed by symmetry and the temporal dynamics intrinsic to current generation and decay that optically induced photocurrents in TaAs are inherent to the underlying crystal symmetry of the transition metal monopnictide family of Weyl semimetals.
Abstract In our previous study, we found that the sonic hedgehog (Shh) signaling pathway is activated in neurons under oxidative stress and plays a neuro-protective role Dai RL, et al. (2011) ...Neurochem Res 36:67–75; we are led to postulate that the Shh might be released by astrocytes, thereby protecting neurons against oxidant injury. In primary cultured astrocytes of rats, we found that treatment with 100 μM H 2 O 2 for 24 h induced a significant increase in the mRNA and protein levels of Shh, Patched1, and Gli-1, and the increase was substantially greater in astrocytes than in neurons. In the coculture systems of astrocytes and neurons under the H 2 O 2 treatment, blocking the Shh signaling pathway with 5E1 (an antibody against the N-terminal domain of Shh) could block the neuroprotective activity of astrocytes on cocultured neurons. In this study, we found that treatment with H 2 O 2 (100–800 μM) for 24 h caused cell death of astrocytes in a concentration-dependent manner. MTT reduction and Trypan Blue exclusion assay showed that exogenous Shh increased survival rate of the H 2 O 2 -treated astrocytes, whereas pretreatment with cyclopamine (a specific inhibitor of the Shh signaling pathway) or 5E1 decreased the survival rate of the H 2 O 2 -treated astrocytes. Shh also inhibited H 2 O 2 -induced apoptosis of astrocytes, and this effect could be partially reversed by cyclopamine. We also found that Shh promoted the phosphorylation of AKT, but had no significant effect on p38 or extracellular signal regulated kinases 1 and 2 (ERK 1/2) in H 2 O 2 -treated astrocytes. Blocking Shh or phosphoinositide 3-kinases (PI3-K)/AKT signaling pathway with cyclopamine or LY294002 decreased the survival rate of astrocytes, induced cell apoptosis, upregulated the expression of Bax, and downregulated the expression of Bcl-2. We are led to conclude that the oxidative stress induces astrocytes to secrete endogenous Shh and exogenous administration of Shh might protect the astrocytes from oxidative stress by activating PI3-K/AKT/Bcl-2 pathway.
The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A ...hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.
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