Hepatitis due to hepatitis B virus(HBV) reactivation can be severe and potentially fatal, but is preventable. HBV reactivation is most commonly reported in patients receiving cancer chemotherapy, ...especially rituximabcontaining therapy for hematological malignancies and those receiving stem cell transplantation. All patients with hematological malignancies receiving anticancer therapy should be screened for active or resolved HBV infection by blood tests for hepatitis B surface antigen(HBs Ag) and antibody to hepatitis B core antigen(antiHBc). Patients found to be positive for HBs Ag should be given prophylactic antiviral therapy to prevent HBV reactivation. For patients with resolved HBV infection, no standard strategy has yet been established to prevent HBV reactivation. There are usually two options. One is pre-emptive therapy guided by serial HBV DNA monitoring, whereby antiviral therapy is given as soon as HBV DNA becomes detectable. However, there is little evidence regarding the optimal interval and period of monitoring. An alternative approach is prophylactic antiviral therapy, especially for patients receiving highrisk therapy such as rituximab, newer generation of anti-CD20 monoclonal antibody, obinutuzumab or hematopoietic stem cell transplantation. This strategy may effectively prevent HBV reactivation and avoid the inconvenience of repeated HBV DNA monitoring. Entecavir or tenofovir are preferred over lamivudine as prophylactic therapy. Although there is no well-defined guideline on the optimal duration of prophylactic therapy, there is growing evidence to recommend continuing prophylactic antiviral therapy for at least 12 mo after cessation of chemotherapy, and even longer for those who receive rituximab or who had high serum HBV DNA levels before the start of immunosuppressive therapy. Many novel agents have recently become available for the treatment of hematological malignancies, and these agents may be associated with HBV reactivation. Although there is currently limited evidence to guide the optimal preventive measures, we recommend antiviral prophylaxis in HBs Ag-positive patients receiving novel treatments, especially the Bruton tyrosine kinase inhibitors and the phosphatidylinositol 3-kinase inhibitors, which are B-cell receptor signaling modulators and reduce proliferation of malignant B-cells. Further studies are needed to clarify the risk of HBV reactivation with these agents and the best prophylactic strategy in the era of targeted therapy for hematological malignancies.
We have conducted a systematic survey for the X-ray properties of millisecond pulsars (MSPs). Currently, there are 47 MSPs with confirmed X-ray detections. We have also placed the upper limits for ...the X-ray emission from the other 36 MSPs by using the archival data. We have normalized their X-ray luminosities Lx and their effective photon indices Γ into a homogeneous data set, which enables us to carry out a detailed statistical analysis. Based on our censored sample, we report a relation of L x 10 31.05 ( E ˙ 10 35 ) 1.31 erg s−1 (2-10 keV) for the MSPs. The inferred X-ray conversion efficiency is found to be lower than the previously reported estimate that could be affected by selection bias. Lx also correlates/anti-correlates with the magnetic field strength at the light cylinder BLC/characteristic age τ. On the other hand, there is no correlation between Lx and their surface magnetic field strength Bs. We have further divided the sample into four classes: (i) black-widows, (ii) redbacks, (iii) isolated MSPs, and (iv) other MSP binaries, and compare the properties among them. We noted that while the rotational parameters and the orbital periods of redbacks and black-widows are similar, Lx of redbacks are significantly higher than those of black-widows in the 2-10 keV band. Also the Γ of redbacks are apparently smaller than those of black-widows, which indicates that the X-ray emission of redbacks are harder than that of black-widows. This can be explained by the different contribution of intrabinary shocks in the X-ray emission of these two classes.
Supernova remnant (SNR)W28 is well known for its classic hadronic scenario, in which the TeV cosmic rays (CRs) released at the early stage of this intermediate-age SNR illuminate nearby molecular ...clouds (MCs). Overwhelming evidence has shown that the northeastern part of the SNR (W28-North) has already encountered the MC clumps. Through this broken shell W28-North, CRs with an energy down to <1 GeV may be able to be injected into nearby MCs. To further verify this hadronic scenario, we first analyze nine years of Fermi-LAT data in/around W28 with energies down to 0.3 GeV. Our Fermi-LAT analysis displays a 10-200 GeV skymap that spatially matches the known TeV sources HESS J1801-233 (W28-North) and HESS J1800-240 A, B, and C (240 A B and C) well. At low energy bands, we have discovered a 0.5-1 GeV blob located to the south of 240 B and C, and a low flux of 0.3-1 GeV at 240 A. A hadronic model is build to explain our analysis results and previous multiwavelength observations of W28. Our model consists of three CR sources: the run-away CRs escaped from a strong shock, the leaked GeV CRs from the broken shell W28-North, and the local CR sea. Through modeling the SNR evolution and the CR acceleration and release, we explain the GeV-TeV emission in/around SNR W28 (except for 240 A) in one model. The damping of the magnetic waves by the neutrals and the decreased acceleration efficiency are both taken into account in our model due to the intermediate age of SNR W28.
Recent observations strongly suggest that the millisecond pulsar binary PSR J1023+0038 has developed an accretion disk since 2013 June. We present a multi-wavelength analysis of PSR J1023+0038, which ...reveals that (1) its gamma-rays suddenly brightened within a few days in 2013 June/July and has remained at a high gamma-ray state for several months; (2) both UV and X-ray fluxes have increased by roughly an order of magnitude; and (3) the spectral energy distribution has changed significantly after the gamma-ray sudden flux change. Time variabilities associated with UV and X-rays are on the order of 100-500 s and 50-100 s, respectively. Our model suggests that a newly formed accretion disk, due to the sudden increase of the stellar wind, could explain the changes of all these observed features. The increase of UV is emitted from the disk, and a new component in gamma-rays is produced by inverse Compton scattering between the new UV component and pulsar wind. The increase of X-rays results from the enhancement of injection pulsar wind energy into the intra-binary shock due to the increase of the stellar wind. We also predict that the radio pulses may be blocked by the evaporated winds from the disk, and the pulsar is still powered by rotation.
We present the results of a detailed investigation of the prompt and afterglow emission in the High Energy Stereoscopic System (H.E.S.S.)-detected GRB 190829A. Swift and Fermi observations of the ...prompt phase of this gamma-ray burst (GRB) reveal two isolated subbursts or episodes, separated by a quiescent phase. The energetic and the spectral properties of the first episode are in stark contrast to the second. The first episode, which has a higher spectral peak ∼120 keV and a low isotropic energy ∼1050 erg is an outlier to the Amati correlation and marginally satisfies the Yonetoku correlation. However, the energetically dominant second episode has lower peak energy and is consistent with the above correlations. We compared this GRB to other low-luminosity GRBs (LLGRBs). Prompt emission of LLGRBs also indicates a relativistic shock breakout origin of the radiation. For GRB 190829A, some of the properties of a shock breakout origin are satisfied. However, the absence of an accompanying thermal component and energy above the shock breakout critical limit precludes a shock breakout origin. In the afterglow, an unusual long-lasting late-time flare of duration ∼104 s is observed. We also analyzed the late-time Fermi Large Area Telescope (LAT) emission that encapsulates the H.E.S.S. detection. Some of the LAT photons are likely to be associated with the source. All of the above observational facts suggest GRB 190829A is a peculiar low-luminosity GRB that is not powered by a shock breakout, and has an unusual rebrightening due to patchy emission or a refreshed shock during the afterglow. Furthermore, our results show that teraelectronvolt-energy photons seem common in both high-luminosity GRBs and LLGRBs.
Plasma DNA fragmentomics is an emerging area in cell-free DNA diagnostics and research. In murine models, it has been shown that the extracellular DNase, DNASE1L3, plays a role in the fragmentation ...of plasma DNA. In humans, DNASE1L3 deficiency causes familial monogenic systemic lupus erythematosus with childhood onset and anti-dsDNA reactivity. In this study, we found that human patients with DNASE1L3 disease-associated gene variations showed aberrations in size and a reduction of a “CC” end motif of plasma DNA. Furthermore, we demonstrated that DNA from DNASE1L3-digested cell nuclei showed a median length of 153 bp with CC motif frequencies resembling plasma DNA from healthy individuals. Adeno-associated virus-based transduction of Dnase1l3 into Dnase1l3-deficient mice restored the end motif profiles to those seen in the plasma DNA of wild-type mice. Our findings demonstrate that DNASE1L3 is an important player in the fragmentation of plasma DNA, which appears to act in a cell-extrinsic manner to regulate plasma DNA size and motif frequency.
Purpose
In our center, patients with anorectal malformation, including males with recto-vesical (RV)/recto-bladder neck (RBN)/recto-prostatic urethral (RU) fistulas, and females with recto-vaginal ...(RV) fistulas have been treated by posterior sagittal anorectoplasty (PSARP) before 2000, and by laparoscopic-assisted anorectal pull-through (LAARP) thereafter. We would like to compare the quality of life (QOL) and long-term defecative function between these two groups of patients 10 years after reconstructive surgery.
Methods
Patients who underwent LAARP between 2001 and 2005 were compared with historical controls treated with PSARP between 1996 and 2000. Degrees of continence were graded by the Krickenbeck classification and Kelly’s score. QOL was assessed by Hirschsprung’s disease/Anorectal Malformation Quality of Life (HAQL) questionnaire. Results were compared using Chi-square test and
t
test.
Results
There were 14 LAARP and 7 PSARP patients. All attained voluntary bowel movements. Moderate to severe soiling (Krickenbeck Grade 2 and 3) was found in 3/14 LAARP (21.4%) and 1/7 PSARP (14.3%) patients,
p
= 1.00. Constipation requiring use of laxatives was present in 3/14 LAARP (28.6%) and 1/7 PSARP (14.3%) patients,
p
= 0.62. Mean Kelly’s scores were 3.79 ± 0.98 (LAARP) and 4.71 ± 1.25 (PSARP),
p
= 0.12. No patient required Malone antegrade continence enema (MACE). The QOL scores based on the HAQL questionnaire were comparable between the two groups in all areas except social functioning, in which the LAARP patients attained a significantly lower mean score (26.4 vs 71.7,
p
= 0.0001).
Conclusion
The 10-year outcome between LAARP and PSARP patients in terms of QOL and defecative function is comparable. Impairment in social functioning in these patients is reflected by the self-reported lower level of functioning.
The first measurements from the CIBER experiment of extragalactic background light (EBL) in near-infrared (NIR) band exhibit a higher intensity than those inferred through γ-ray observations. Recent ...theoretical-EBL intensities are typically consistent with the very high energy (VHE) γ-ray observations. Yet, it is possible that the excess NIR radiation is a new component of EBL and not in tension with the TeV spectra of distant blazars, since the hypothetical axionlike particle (ALP) may lead to a reduced opacity of the Universe for VHE γ-rays. In order to probe whether the excess component arises mainly from EBL, thirteen observed spectra in high energy and VHE ranges from ten distant TeV BL Lac objects are fitted by four theoretical spectra which involve theoretical EBL (Gilmore et al.), Gilmore's EBL model including photon/ALP coupling, Gilmore's EBL with CIBER excess and the latter including photon/ALP coupling respectively. We find the goodness of fit for the model with CIBER excess can be improved with a significance of 7.6σ after including the photon/ALP coupling. Thus, the ALP/photon mixing mechanism can effectively alleviate the tension; However, the Gilmore EBL model, on the whole, is more compatible with the observed spectra compared to those with ALP, although individual blazars such as PKS 1424 + 240 and 1ES 1101-232 prefer the ALP-model. Our results suggest that the recent EBL models can solely explain the VHE γ-ray observations, and assuming the existence of the ALP to alleviate the tension is not required in a statistical sense, thus the excess over the EBL models is less likely to be a new EBL component.
Expression of hepcidin, the key hormone governing iron transport, is reduced by anemia in a manner which appears dependent on increased bone marrow activity. The temporal associations between plasma ...hepcidin and other iron parameters were examined in healthy humans after erythropoietin administration and venesection. Profound hepcidin suppression appeared abruptly 24 hours after subcutaneous erythropoietin (P=0.003), and was near maximal at onset, with peak (mid-afternoon) levels reduced by 73.2%, gradually recovering over the following two weeks. Minor changes in circulating iron, soluble transferrin receptor and growth differentiation factor-15 were observed after the reduction in hepcidin. Similar but more gradual changes in these parameters were observed after reducing hematocrit by removal of 250 mL blood. These human studies confirm the importance of a rapidly responsive marrow-hepcidin axis in regulating iron supply in vivo, and suggest that this axis is regulated by factors other than circulating iron, soluble transferrin receptor or growth differentiation factor-15.
We report the analysis result of UV/X-ray emission from AR Scorpii, which is an intermediate polar (IP) composed of a magnetic white dwarf and an M-type star, with the XMM-Newton data. The X-ray/UV ...emission clearly shows a large variation over the orbit, and their intensity maximum (or minimum) is located at the superior conjunction (or inferior conjunction) of the M star orbit. The hardness ratio of the X-ray emission shows a small variation over the orbital phase and shows no indication of the absorption by an accretion column. These properties are naturally explained by the emission from the M star surface rather than that from the accretion column on the white dwarf's (WD) star, which is similar to usual IPs. Additionally, the observed X-ray emission also modulates with the WD's spin with a pulse fraction of ∼14%. The peak position is aligned in the optical/UV/X-ray band. This supports the hypothesis that the electrons in AR Scorpii are accelerated to a relativistic speed and emit non-thermal photons via the synchrotron radiation. In the X-ray bands, evidence of the power-law spectrum is found in the pulsed component, although the observed emission is dominated by the optically thin thermal plasma emissions with several different temperatures. It is considered that the magnetic dissipation/reconnection process on the M star surface heats up the plasma to a temperature of several keV and also accelerates the electrons to the relativistic speed. The relativistic electrons are trapped in the WD's closed magnetic field lines by the magnetic mirror effect. In this model, the observed pulsed component is explained by the emissions from the first magnetic mirror point.
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