Simultaneous enhancement of out-coupling efficiency, internal quantum efficiency, and color purity in thermally activated delayed fluorescence (TADF) emitters is highly desired for the practical ...application of these materials. We designed and synthesized two isomeric TADF emitters, 2DPyM-mDTC and 3DPyM-pDTC, based on di(pyridinyl)methanone (DPyM) cores as the new electron-accepting units and di(tert-butyl)carbazole (DTC) as the electron-donating units. 3DPyM-pDTC, which is structurally nearly planar with a very small ΔE ST, shows higher color purity, horizontal ratio, and quantum yield than 2DPyM-mDTC, which has a more flexible structure. An electroluminescence device based on 3DPyM-pDTC as the dopant emitter can reach an extremely high external quantum efficiency of 31.9% with a pure blue emission. This work also demonstrates a way to design materials with a high portion of horizontal molecular orientation to realize a highly efficient pure-blue device based on TADF emitters.
Abstract
SARS-CoV-2 infection of children leads to a mild illness and the immunological differences with adults are unclear. Here, we report SARS-CoV-2 specific T cell responses in infected adults ...and children and find that the acute and memory CD4
+
T cell responses to structural SARS-CoV-2 proteins increase with age, whereas CD8
+
T cell responses increase with time post-infection. Infected children have lower CD4
+
and CD8
+
T cell responses to SARS-CoV-2 structural and ORF1ab proteins when compared with infected adults, comparable T cell polyfunctionality and reduced CD4
+
T cell effector memory. Compared with adults, children have lower levels of antibodies to β-coronaviruses, indicating differing baseline immunity. Total T follicular helper responses are increased, whilst monocyte numbers are reduced, indicating rapid adaptive co-ordination of the T and B cell responses and differing levels of inflammation. Therefore, reduced prior β-coronavirus immunity and reduced T cell activation in children might drive milder COVID-19 pathogenesis.
Abstract
Background
A novel coronavirus of zoonotic origin (2019-nCoV) has recently been identified in patients with acute respiratory disease. This virus is genetically similar to SARS coronavirus ...and bat SARS-like coronaviruses. The outbreak was initially detected in Wuhan, a major city of China, but has subsequently been detected in other provinces of China. Travel-associated cases have also been reported in a few other countries. Outbreaks in health care workers indicate human-to-human transmission. Molecular tests for rapid detection of this virus are urgently needed for early identification of infected patients.
Methods
We developed two 1-step quantitative real-time reverse-transcription PCR assays to detect two different regions (ORF1b and N) of the viral genome. The primer and probe sets were designed to react with this novel coronavirus and its closely related viruses, such as SARS coronavirus. These assays were evaluated using a panel of positive and negative controls. In addition, respiratory specimens from two 2019-nCoV-infected patients were tested.
Results
Using RNA extracted from cells infected by SARS coronavirus as a positive control, these assays were shown to have a dynamic range of at least seven orders of magnitude (2x10−4-2000 TCID50/reaction). Using DNA plasmids as positive standards, the detection limits of these assays were found to be below 10 copies per reaction. All negative control samples were negative in the assays. Samples from two 2019-nCoV-infected patients were positive in the tests.
Conclusions
The established assays can achieve a rapid detection of 2019n-CoV in human samples, thereby allowing early identification of patients.
Summary
Background
Ustekinumab, an interleukin (IL)‐12 and IL‐23 blocker, has emerged as a new therapeutic option for patients with psoriasis. It is generally well tolerated but safety data on the ...use of ustekinumab in patients with viral hepatitis are limited.
Objective
To assess the safety profile of ustekinumab in the treatment of patients with psoriasis who have concomitant hepatitis B or hepatitis C.
Methods
This study included 18 patients with concurrent psoriasis and hepatitis B virus (HBV) infection (14 patients) or hepatitis C virus (HCV) infection (four patients) who were treated with at least two ustekinumab injections. Viral loads were measured at baseline and each time before the administration of ustekinumab. Relevant clinical data were recorded.
Results
Among 11 patients positive for hepatitis B surface antigen (HBsAg), two out of the seven (29%) patients who did not receive antiviral prophylaxis exhibited HBV reactivation during ustekinumab treatment. No viral reactivation was observed in the three occult HBV‐infected patients (HBsAg‐negative/hepatitis B core antibody‐positive patients). One patient with HCV, liver cirrhosis and treated hepatocellular carcinoma (HCC) experienced HCV reactivation and recurrent HCC during the ustekinumab treatment. No significant increase in aminotransferase levels was observed in any patient.
Conclusions
Antiviral prophylaxis appears to minimize the risk of viral reactivation in patients with concurrent psoriasis and HBV infection. Without effective anti‐viral prophylaxis, the risk/benefit of ustekinumab treatment should be carefully assessed in patients with psoriasis and HBV or HCV infection and/or HCC. Close monitoring for HBV and HCV viral load is recommended, particularly for patients with high‐risk factors. Serum aminotransferase determination may not be useful for early detection of viral reactivation.
What's already known about this topic?
Interleukin (IL)‐12 plays a central role in mounting an immune response directed towards the elimination of pathogens.
Ustekinumab, an IL‐12/23 blocker may theoretically carry the risk of hepatitis B (HBV) and hepatitis C virus (HCV) reactivation with its use.
What does this study add?
Ustekinumab appears to be well tolerated in patients with concurrent psoriasis and HBV infection under antiviral prophylaxis.
The risk of HCV reactivation during ustekinumab treatment does exist and appropriate vigilance should be exercised, especially in specific high‐risk patient groups.
Summary
Background
Ustekinumab, an interleukin‐12/23 inhibitor, is effective in the treatment of psoriasis. A recent Italian study showed more favourable response to ustekinumab in patients with ...positive human leucocyte antigen (HLA)‐Cw6. Nonetheless, there are differences in genetic susceptibility to psoriasis between races, and no studies have specifically assessed the candidate genetic markers in predicting therapy outcome in Chinese patients with psoriasis treated with ustekinumab.
Objectives
To determine whether HLA gene polymorphisms can predict the response to ustekinumab in Chinese patients with psoriasis.
Methods
Sixty‐six patients with psoriasis treated with ustekinumab were included in the study, and the effectiveness of ustekinumab therapy was evaluated at weeks 0, 16 and 28 by Psoriasis Area and Severity Index (PASI).
Results
More HLA‐Cw6‐positive patients achieved a PASI 75 response at week 4 compared with HLA‐Cw6‐negative patients (38% vs. 9%, P = 0·019). Similarly, at week 16, patients carrying the HLA‐Cw6 allele showed a higher likelihood of achieving PASI 50, 75 and 90 than Cw6‐negative patients, although this was not statistically significant. At week 28, a significantly higher percentage of HLA‐Cw6‐positive patients maintained PASI 90 response compared with Cw6‐negative patients (63% vs. 26%, P = 0·035). Further analysis of other HLA allele polymorphisms did not show significant associations with therapeutic response to ustekinumab.
Conclusions
This pharmacogenetic study provides preliminary data indicating that positive HLA‐Cw6 is associated with a good response to ustekinumab treatment in Chinese patients with psoriasis.
What's already known about this topic?
Biological therapies have revolutionized the treatment of psoriasis. Variability in genes involved in the immunological pathways of biological therapy may account for the different treatment outcomes.
Human leucocyte antigen (HLA)‐Cw6 is the major psoriasis susceptibility gene and has a strong association with clinical psoriasis phenotypes.
Studies investigating potential predictors for response to biologics are limited, particularly in Asian populations.
What does this study add?
Our study showed that HLA‐Cw6‐positive patients have a faster response and maintain a longer treatment response to ustekinumab than HLA‐Cw6‐negative patients.
HLA‐Cw6 can be a pragmatic predictor for the response to ustekinumab not only in white patients but also in Chinese patients with psoriasis.
These results will help dermatologists in guiding therapeutic decisions.
The series battery string or supercapacitor string automatic equalization system based on quasi-resonant switched-capacitor converter is presented in this paper. It realizes the zero-voltage gap ...between cells and allows maximum energy recovery in a series battery system or supercapacitor system. It not only inherits the advantage of conventional switched-capacitor battery cell balancing system, but also overcomes the drawback of conduction loss, switching loss, and finite voltage difference among battery cells. All switches are MOSFET and controlled by just a pair of complementary signals in synchronous trigger pattern and the resonant tanks operate alternatively between the two states of charging and discharging. Zero-current switching and zero-voltage gap are achieved in this paper. Different resonant tank designs can meet the needs of different balancing time to meet the needs of different energy storage devices. Experimental results indicate that the efficiency of the system is high exceeding 98%. The system is very suitable for balancing used in battery management system.
Because the surface-to-volume ratio of quasi-two-dimensional materials is extremely high, understanding their surface characteristics is crucial for practically controlling their intrinsic properties ...and fabricating p-type and n-type layered semiconductors. Van der Waals crystals are expected to have an inert surface because of the absence of dangling bonds. However, here we show that the surface of high-quality synthesized molybdenum disulfide (MoS2) is a major n-doping source. The surface electron concentration of MoS2 is nearly four orders of magnitude higher than that of its inner bulk. Substantial thickness-dependent conductivity in MoS2 nanoflakes was observed. The transfer length method suggested the current transport in MoS2 following a two-dimensional behavior rather than the conventional three-dimensional mode. Scanning tunneling microscopy and angle-resolved photoemission spectroscopy measurements confirmed the presence of surface electron accumulation in this layered material. Notably, the in situ-cleaved surface exhibited a nearly intrinsic state without electron accumulation.
Activation of Akt signaling pathway has been suggested involving in chemoresistance, metastasis and tumorigenesis of gastric cancer. However, the mechanism of Akt regulation in gastric cancer is not ...fully understood. RUNX3, which was first identified as a transcription factor, suppresses gastric tumorigenesis through regulating expression of target genes. Here, we found that restoration of RUNX3 significantly downregulates the protein and mRNA expression of Akt1 in gastric cancer cell lines, AGS and SNU-1. Knockdown of RUNX3 upregulates protein and mRNA expression of Akt1 in normal gastric epithelial cell line, GES-1. The negative correlation of RUNX3 and Akt expression and downstream β-catenin/cyclin D1 effectors was further confirmed in AGS and GES-1 cell lines, as well as clinical specimens of gastric cancer. We identified two RUNX3-binding sites in Akt1 promoter and the binding of RUNX3 on Akt1 promoter significantly inhibits Akt1 expression. The RUNX3-mediated inhibition of Akt1 caused β-catenin protein degradation and then cyclin D1 downregulation. Restoration of cyclin D1 reverses cell growth inhibition and G1 phase arrest induced by RUNX3 in gastric cancer cells. Our results show that loss of RUNX3 expression can enhance the Akt1-mediated signaling pathway and promote the tumorigenesis process in human gastric cancer.
The effect of particle-size distribution on the one-dimensional compressive behaviour of granular soil materials was investigated using the discrete-element method (DEM), and the results were ...compared with published experimental data with similar gradations. The particles used in this study were spherical, and their size range mimicked various power-law distributions. The contact formulation was calibrated such that the different compressibility and initial specific volume of non-uniform assemblies depended purely on the interaction of different particle sizes of the non-uniform gradations. This behaviour was visualised in the DEM simulations. As these particles rearranged themselves, these regions contributed to a higher volumetric compression. It was also found that the coordination number of DEM particles significantly increased with better gradations.
Infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19), which has been characterized by fever, respiratory, and gastrointestinal ...symptoms as well as shedding of virus RNA into feces. We performed a systematic review and meta-analysis of published gastrointestinal symptoms and detection of virus in stool and also summarized data from a cohort of patients with COVID-19 in Hong Kong.
We collected data from the cohort of patients with COVID-19 in Hong Kong (N = 59; diagnosis from February 2 through February 29, 2020),and searched PubMed, Embase, Cochrane, and 3 Chinese databases through March 11, 2020, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We analyzed pooled data on the prevalence of overall and individual gastrointestinal symptoms (loss of appetite, nausea, vomiting, diarrhea, and abdominal pain or discomfort) using a random effects model.
Among the 59 patients with COVID-19 in Hong Kong, 15 patients (25.4%) had gastrointestinal symptoms, and 9 patients (15.3%) had stool that tested positive for virus RNA. Stool viral RNA was detected in 38.5% and 8.7% among those with and without diarrhea, respectively (P = .02). The median fecal viral load was 5.1 log10 copies per milliliter in patients with diarrhea vs 3.9 log10 copies per milliliter in patients without diarrhea (P = .06). In a meta-analysis of 60 studies comprising 4243 patients, the pooled prevalence of all gastrointestinal symptoms was 17.6% (95% confidence interval CI, 12.3–24.5); 11.8% of patients with nonsevere COVID-19 had gastrointestinal symptoms (95% CI, 4.1–29.1), and 17.1% of patients with severe COVID-19 had gastrointestinal symptoms (95% CI, 6.9–36.7). In the meta-analysis, the pooled prevalence of stool samples that were positive for virus RNA was 48.1% (95% CI, 38.3–57.9); of these samples, 70.3% of those collected after loss of virus from respiratory specimens tested positive for the virus (95% CI, 49.6–85.1).
In an analysis of data from the Hong Kong cohort of patients with COVID-19 and a meta-analysis of findings from publications, we found that 17.6% of patients with COVID-19 had gastrointestinal symptoms. Virus RNA was detected in stool samples from 48.1% patients, even in stool collected after respiratory samples had negative test results. Health care workers should therefore exercise caution in collecting fecal samples or performing endoscopic procedures in patients with COVID-19, even during patient recovery.
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