The development of high-performance near-infrared organic light-emitting diodes is hindered by strong non-radiative processes as governed by the energy gap law. Here, we show that exciton ...delocalization, which serves to decouple the exciton band from highly vibrational ladders in the S0 ground state, can bring substantial enhancements in the photoluminescence quantum yield of emitters, bypassing the energy gap law. Experimental proof is provided by the design and synthesis of a series of new Pt(ii) complexes with a delocalization length of 5–9 molecules that emit at 866–960 nm with a photoluminescence quantum yield of 5–12% in solid films. The corresponding near-infrared organic light-emitting diodes emit light with a 930 nm peak wavelength and a high external quantum efficiency up to 2.14% and a radiance of 41.6 W sr−1 m−2. Both theoretical and experimental results confirm the exciton–vibration decoupling strategy, which should be broadly applicable to other well-aligned molecular solids.Pt(ii) complexes allow the fabrication of efficient near-infrared organic light-emitting diodes that operate beyond the 900 nm region.
Abstract
Short-term, systemic expression of the Yamanaka reprogramming factors (
Oct-3/4
,
Sox2
,
Klf4
and
c-Myc
OSKM) has been shown to rejuvenate aging cells and promote tissue regeneration in ...vivo. However, the mechanisms by which OSKM promotes tissue regeneration are unknown. In this work, we focus on a specific tissue and demonstrate that local expression of OSKM, specifically in myofibers, induces the activation of muscle stem cells or satellite cells (SCs), which accelerates muscle regeneration in young mice. In contrast, expressing OSKM directly in SCs does not improve muscle regeneration. Mechanistically, expressing OSKM in myofibers regulates the expression of genes important for the SC microenvironment, including upregulation of p21, which in turn downregulates
Wnt4
. This is critical because Wnt4 is secreted by myofibers to maintain SC quiescence. Thus, short-term induction of the Yamanaka factors in myofibers may promote tissue regeneration by modifying the stem cell niche.
We demonstrate directed translocation of ClO4− anions from cationic to neutral binding site along the synthetized BPym‐OH dye molecule that exhibits coupled excited‐state intramolecular ...proton‐transfer (ESIPT) and charge‐transfer (CT) reaction (PCCT). The results of steady‐state and time‐resolved spectroscopy together with computer simulation and modeling show that in low polar toluene the excited‐state redistribution of electronic charge enhanced by ESIPT generates the driving force, which is much stronger than by CT reaction itself and provides more informative gigantic shifts of fluorescence spectra signaling on ultrafast ion motion. The associated with ion translocation red‐shifted fluorescence band (at 750 nm, extending to near‐IR region) appears at the time ~83 ps as a result of electrochromic modulation of PCCT reaction. It occurs at substantial delay to PCCT that displayed fluorescence band at 640 nm and risetime of <200 fs. Thus, it becomes possible to visualize the manifestations of light‐triggered ion translocation and of its driving force by fluorescence techniques and to separate them in time and energy domains.
The light‐triggered translocation of ClO4− anion from cationic to neutral‐binding site along BPym‐OH dye is visualized by emission. The combination of time‐resolved fluorescence and molecular dynamic simulation allows its description in time and energy domains. This reaction generates dramatically red‐shifted fluorescence extending to near‐IR that appears at ~83 ps, resulting from electrochromic modulation of coupled proton‐electron transfer.
Abstract
Human pluripotent stem cell (hPSC)-derived pancreatic β cells are an attractive cell source for treating diabetes. However, current derivation methods remain inefficient, heterogeneous, and ...cell line dependent. To address these issues, we first devised a strategy to efficiently cluster hPSC-derived pancreatic progenitors into 3D structures. Through a systematic study, we discovered 10 chemicals that not only retain the pancreatic progenitors in 3D clusters but also enhance their potentiality towards NKX6.1+/INS+ β cells. We further systematically screened signaling pathway modulators in the three steps from pancreatic progenitors toward β cells. The implementation of all these strategies and chemical combinations resulted in generating β cells from different sources of hPSCs with high efficiency. The derived β cells are functional and can reverse hyperglycemia in mice within two weeks. Our protocol provides a robust platform for studying human β cells and developing hPSC-derived β cells for cell replacement therapy.
To evaluate the performance of the Prostate Health Index (PHI) in magnetic resonance imaging-transrectal ultrasound (MRI-TRUS) fusion prostate biopsy for the detection of clinically significant ...prostate cancer (csPCa). We prospectively enrolled 164 patients with at least one Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) ≥ 3 lesions who underwent MRI-TRUS fusion prostate biopsy. Of the PSA-derived biomarkers, the PHI had the best performance in predicting csPCa (AUC 0.792, CI 0.707-0.877) in patients with PI-RADS 4/5 lesions. Furthermore, the predictive power of PHI was even higher in the patients with PI-RADS 3 lesions (AUC 0.884, CI 0.792-0.976). To minimize missing csPCa, we used a PHI cutoff of 27 and 7.4% of patients with PI-RADS 4/5 lesions could have avoided a biopsy. At this level, 2.0% of cases with csPCa would have been missed, with sensitivity and NPV rates of 98.0% and 87.5%, respectively. However, the subgroup of PI-RADS 3 was too small to define the optimal PHI cutoff. PHI was the best PSA-derived biomarker to predict csPCa in MRI-TRUS fusion prostate biopsies in men with PI-RADS ≥ 3 lesions, especially for the patients with PI-RADS 3 lesions who gained the most value.
Human trisomies can alter cellular phenotypes and produce congenital abnormalities such as Down syndrome (DS). Here we have generated induced pluripotent stem cells (iPSCs) from DS fibroblasts and ...introduced a TKNEO transgene into one copy of chromosome 21 by gene targeting. When selecting against TKNEO, spontaneous chromosome loss was the most common cause for survival, with a frequency of ∼10−4, while point mutations, epigenetic silencing, and TKNEO deletions occurred at lower frequencies in this unbiased comparison of inactivating mutations. Mitotic recombination events resulting in extended loss of heterozygosity were not observed in DS iPSCs. The derived, disomic cells proliferated faster and produced more endothelia in vivo than their otherwise isogenic trisomic counterparts, but in vitro hematopoietic differentiation was not consistently altered. Our study describes a targeted removal of a human trisomy, which could prove useful in both clinical and research applications.
► Trisomy correction in Down syndrome iPSCs by gene targeting and negative selection ► Chromosome loss more frequent than other types of mutations ► Comparison of isogenic disomic and trisomic cell lines ► Trisomy 21 slows iPSC proliferation and reduces endothelial differentiation
Objective
Ultrasound shear wave elastography is an objective tool to evaluate the stiffness of human tissues. Patients with sialolithiasis could be treated by interventional sialendoscopy with a high ...success rate. Sialolithiasis could be extracted, and the diseased gland could be preserved and evaluated after treatment. Whether ultrasound shear wave elastography could be used for objective outcome measurement and short‐term follow‐up of the parenchyma of gland in patients with sialolithiasis remains unclear.
Methods
This retrospective self‐controlled study was conducted. Patients with sialolithiasis treated by interventional sialendoscopy and followed by high‐resolution ultrasound shear wave elastography were selected between January and September 2017.
Results
Seventeen patients with sialolithiasis (mean age: 39.63 ± 12.49 years), including 10 women and 7 men, were enrolled. Fifteen patients had sialolithiasis in the submandibular gland and two in the parotid gland. The preoperative value of shear wave velocity was significantly higher in the diseased gland than in the contralateral normal gland (p < .001; 95% confidence interval CI, 0.3915–0.6046). After successful treatment by interventional sialendoscopy surgery, the shear wave velocity of the diseased gland decreased significantly (p = 0.001; 95% CI, −0.38792 to −0.20474). However, there was a significant difference between the diseased and contralateral normal glands (p = 0.001; 95% CI, 0.0423–0.2895) after 1.55 months of surgery.
Conclusion
Ultrasound shear wave elastography could be an adjuvant tool to distinguish sialolithiasis‐affected diseased glands from contralateral normal glands and assess the short‐term treatment outcome objectively. The changing trend of shear wave velocity could help monitor the healing process of the parenchyma in the diseased gland after treatment.
Level of Evidence
4
Ultrasound shear wave elastography is an objective and reliable tool to differentiate diseased glands from normal glands and assess the treatment outcome in patients with sialolithiasis in a short‐term follow‐up. The changing trend of shear wave velocity enables us to monitor the healing process of parenchyma in the diseased gland after treatment.
The accuracy in diagnosing prostate cancer (PCa) has increased with the development of multiparametric magnetic resonance imaging (mpMRI). Biparametric magnetic resonance imaging (bpMRI) was found to ...have a diagnostic accuracy comparable to mpMRI in detecting PCa. However, prostate MRI assessment relies on human experts and specialized training with considerable inter-reader variability. Deep learning may be a more robust approach for prostate MRI assessment. Here we present a method for autosegmenting the prostate zone and cancer region by using SegNet, a deep convolution neural network (DCNN) model. We used PROSTATEx dataset to train the model and combined different sequences into three channels of a single image. For each subject, all slices that contained the transition zone (TZ), peripheral zone (PZ), and PCa region were selected. The datasets were produced using different combinations of images, including T2-weighted (T2W) images, diffusion-weighted images (DWI) and apparent diffusion coefficient (ADC) images. Among these groups, the T2W + DWI + ADC images exhibited the best performance with a dice similarity coefficient of 90.45% for the TZ, 70.04% for the PZ, and 52.73% for the PCa region. Image sequence analysis with a DCNN model has the potential to assist PCa diagnosis.
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