Several studies relying on the improvements to the important oxygen reduction reaction (ORR) activity for increasing the performance of fuel cells have been reported. However, the application of ...catalyst conditions used for realizing the excellent activity in a half‐cell to a single‐cell does not guarantee the translation of the excellent performance. Therefore, we investigated the performance characteristics of various types of commercially available catalysts, including alloy catalysts, and compared the trends between the half‐cells and single‐cells using linear scan voltammetry (LSV), polarization curves (IVP), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS) measurements. Furthermore, regression analysis was performed to identify the influential factors for examining the complex relationship between the half‐cell and single‐cell performance parameters. The study reveals, that it is highly challenging to express the performances of the catalyst and single‐cell using isolated factors. Additionally, even though the measured activity of the catalyst in a half‐cell is higher than that in the other half‐cells, the difference does not manifest significantly in the single‐cell when the conditions required for its activity are not optimized, indicating that the overall performance of the fuel cell membrane electrode assembly (MEA) is not determined solely by the catalyst.
Strong-coupling between excitons and confined photonic modes can lead to the formation of new quasi-particles termed exciton-polaritons which can display a range of interesting properties such as ...super-fluidity, ultrafast transport and Bose-Einstein condensation. Strong-coupling typically occurs when an excitonic material is confided in a dielectric or plasmonic microcavity. Here, we show polaritons can form at room temperature in a range of chemically diverse, organic semiconductor thin films, despite the absence of an external cavity. We find evidence of strong light-matter coupling via angle-dependent peak splittings in the reflectivity spectra of the materials and emission from collective polariton states. We additionally show exciton-polaritons are the primary photoexcitation in these organic materials by directly imaging their ultrafast (5 × 10
m s
), ultralong (~270 nm) transport. These results open-up new fundamental physics and could enable a new generation of organic optoelectronic and light harvesting devices based on cavity-free exciton-polaritons.
Positron emission tomography (PET) tracers has the potential to revolutionize cancer imaging and diagnosis. PET tracers offer non-invasive quantitative imaging in biotechnology and biomedical ...applications, but it requires radioisotopes as radioactive imaging tracers or radiopharmaceuticals.
This paper reports the synthesis of
F-nGO-PEG by covalently functionalizing PEG with nano-graphene oxide, and its excellent stability in physiological solutions. Using a green synthesis route, nGO is then functionalized with a biocompatible PEG polymer to acquire high stability in PBS and DMEM.
The radiochemical safety of
F-nGO-PEG was measured by a reactive oxygen species and cell viability test. The biodistribution of
F-nGO-PEG could be observed easily by PET, which suggested the significantly high sensitivity tumor uptake of
F-nGO-PEG and in a tumor bearing CT-26 mouse compared to the control.
F-nGO-PEG was applied successfully as an efficient radiotracer or drug agent in vivo using PET imaging. This article is expected to assist many researchers in the fabrication of
F-labeled graphene-based bio-conjugates with high reproducibility for applications in the biomedicine field.
In renal cell carcinoma, transglutaminase 2 (TGase 2) crosslinks p53 in autophagosomes, resulting in p53 depletion and the tumor's evasion of apoptosis. Inhibition of TGase 2 stabilizes p53 and ...induces tumor cells to enter apoptosis. This study explored the mechanism of TGase 2-dependent p53 degradation. We found that TGase 2 competes with human double minute 2 homolog (HDM2) for binding to p53; promotes autophagy-dependent p53 degradation in renal cell carcinoma (RCC) cell lines under starvation; and binds to p53 and p62 simultaneously without ubiquitin-dependent recognition of p62. The bound complex does not have crosslinking activity. A binding assay using a series of deletion mutants of p62, p53 and TGase 2 revealed that the PB1 (Phox and Bem1p-1) domain of p62 (residues 85-110) directly interacts with the β-barrel domains of TGase 2 (residues 592-687), whereas the HDM2-binding domain (transactivation domain, residues 15-26) of p53 interacts with the N terminus of TGase 2 (residues 1-139). In addition to the increase in p53 stability due to TGase 2 inhibition, the administration of a DNA-damaging anti-cancer drug such as doxorubicin-induced apoptosis in RCC cell lines and synergistically reduced tumor volume in a xenograft model. Combination therapy with a TGase 2 inhibitor and a DNA-damaging agent may represent an effective therapeutic approach for treating RCC.
Using prostate-specific antigen (PSA) for prostate cancer (PCa) screening led to overinvestigation and overdiagnosis of indolent PCa. We aimed to investigate the value of prostate health index (PHI) ...and magnetic resonance imaging (MRI) prostate in an Asian PCa screening program. Men aged 50-75 years were prospectively recruited from a community-based PSA screening program. Men with PSA 4.0-10.0 ng ml−1 had PHI result analyzed. MRI prostate was offered to men with PSA 4.0-50.0 ng ml−1. A systematic prostate biopsy was offered to men with PSA 4.0-9.9 ng ml−1 and PHI ≥35, or PSA 10.0-50.0 ng ml−1. Additional targeted prostate biopsy was offered if they had PI-RADS score ≥3. Clinically significant PCa (csPCa) was defined as the International Society of Urological Pathology (ISUP) grade group (GG) ≥2 or ISUP GG 1 with involvement of ≥30% of total systematic cores. In total, 12.8% (196/1536) men had PSA ≥4.0 ng ml−1. Among 194 men with PSA 4.0-50.0 ng ml−1, 187 (96.4%) received MRI prostate. Among them, 28.3% (53/187) had PI-RADS ≥3 lesions. Moreover, 7.0% (107/1536) men were indicated for biopsy and 94.4% (101/107) men received biopsy. Among the men received biopsy, PCa, ISUP GG ≥2 PCa, and csPCa was diagnosed in 42 (41.6%), 24 (23.8%), and 34 (33.7%) men, respectively. Compared with PSA/PHI pathway in men with PSA 4.0-50.0 ng ml−1, additional MRI increased diagnoses of PCa, ISUP GG ≥2 PCa, and csPCa by 21.2% (from 33 to 40), 22.2% (from 18 to 22), and 18.5% (from 27 to 32), respectively. The benefit of additional MRI was only observed in PSA 4.0-10.0 ng ml−1, and the number of MRI needed to diagnose one additional ISUP GG ≥2 PCa was 20 in PHI ≥35 and 94 in PHI <35. Among them, 45.4% (89/196) men with PSA ≥4.0 ng ml−1 avoided unnecessary biopsy with the use of PHI and MRI. A screening algorithm with PSA, PHI, and MRI could effectively diagnose csPCa while reducing unnecessary biopsies. The benefit of MRI prostate was mainly observed in PSA 4.0-9.9 ng ml−1 and PHI ≥35 group. PHI was an important risk stratification step for PCa screening.
Inhibiting the expression of the HIV-1 coreceptor CCR5 holds great promise for controlling HIV-1 infection in patients. Here we report stable knockdown of human CCR5 by a short hairpin RNA (shRNA) in ...a humanized bone marrow/liver/thymus (BLT) mouse model. We delivered a potent shRNA against CCR5 into human fetal liver-derived CD34+ hematopoietic progenitor/stem cells (HPSCs) by lentiviral vector transduction. We transplanted vector-transduced HPSCs solidified with Matrigel and a thymus segment under the mouse kidney capsule. Vector-transduced autologous CD34+ cells were subsequently injected in the irradiated mouse, intended to create systemic reconstitution. CCR5 expression was down-regulated in human T cells and monocytes/macrophages in systemic lymphoid tissues, including gut-associated lymphoid tissue, the major site of HIV-1 replication. The shRNA-mediated CCR5 knockdown had no apparent adverse effects on T-cell development as assessed by polyclonal T-cell receptor Vβ family development and naive/memory T-cell differentiation. CCR5 knockdown in the secondary transplanted mice suggested the potential of long-term hematopoietic reconstitution by the shRNA-transduced HPSCs. CCR5 tropic HIV-1 infection was effectively inhibited in mouse-derived human splenocytes ex vivo. These results demonstrate that lentiviral vector delivery of shRNA into human HPSCs could stably down-regulate CCR5 in systemic lymphoid organs in vivo.
Background
The fecal immunochemical test (FIT) is a cost‐effective colorectal cancer (CRC) screening tool. However, longitudinal adherence, a factor that is critical to the success to any FIT‐based ...screening program, often is poor. The authors hypothesized that reminders sent via mobile messengers, such as WhatsApp, improve such adherence.
Methods
In the current single‐blind, randomized study, subjects from an opportunistic FIT screening program who had a negative FIT result the year prior were randomly allocated (1:1) to receive either a 1‐off reminder via the WhatsApp messenger (WR) 1 month prior to the due appointments or no reminder (NR). All subjects were blinded to study participation and group allocation. At 24 months after randomization, a crossover of intervention was performed among those individuals who remained in the FIT program. The primary outcome was FIT adherence, defined as the pick‐up and on‐time return of the FIT. The secondary outcome was FIT adherence after the crossover.
Results
A total of 500 subjects were randomized to receive WR (250 subjects) or NR (250 subjects). Three individuals were excluded from analysis (1 died and 2 underwent colonoscopy). Both the FIT pick‐up rate (80.3% vs 59.3%; P < .001) and return rate (79.9% vs 57.3%; P < .001) were significantly higher in the WR group compared with the NR group. After crossover of intervention (452 subjects), the WR group again was found to have a higher FIT pick‐up rate (79.1% vs 52.9%; P < .001) and return rate (78.2% vs 52.4%; P < .001).
Conclusions
Text reminders sent via mobile messenger appear to improve the longitudinal adherence to FIT‐based opportunistic CRC screening programs. The routine use of this technology in CRC screening should be considered.
The fecal immunochemical test is a cost‐effective screening tool for colorectal cancer. The results of the current single‐blind, crossover, randomized controlled study demonstrate that longitudinal adherence to a stool‐based screening program can be significantly improved by reminders sent via a mobile‐based messenger (WhatsApp Messenger).
A double‐layered nanoporous membrane suitable for virus filtration has been fabricated. The top layer has cylindrical pores with diameters of 15 nm and a narrow pore size distribution (see figure). ...The bottom support layer is a conventional microfiltration membrane. This asymmetric membrane completely blocks human rhinovirus type 14 (colored green) from penetrating into pores, while proteins such as bovine serum albumin (colored yellow) freely pass through the pores.
Particulate matter and air pollution in Korea are becoming worse. There is a lack of research regarding the impact of particulate matter on patients with COPD. Therefore, the purpose of this study ...was to investigate the effects of various air pollution factors, including particulate matter, on the incidence rate of severe acute exacerbations of COPD (AECOPD) events.
We analyzed the relationship between air pollutants and AECOPD events that required hospitalization at Guro Hospital in Korea from January 1, 2015 to May 31, 2017. We used general linear models with Poisson distribution and log-transformation to obtain adjusted relative risk (RR). We conducted further analysis through the Comprehensive Air-quality Index (CAI) that is used in Korea.
Among various other air pollutants, particulate matter was identified as a major source of air pollution in Korea. When the CAI score was over 50, the incidence rate of severe AECOPD events was statistically significantly higher RR 1.612, 95% CI, 1.065-2.440,
=0.024. Additionally, the particulate matter levels 3 days before hospitalization were statistically significant RR 1.003, 95% CI, 1.001-1.005,
=0.006.
Particulate matter and air pollution increase the incidence rate of severe AECOPD events. COPD patients should be cautioned against outdoor activities when particulate matter levels are high.
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