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Although metal-halide perovskite nanocrystals (NCs) have garnered significant attention for optoelectronic applications, the presence of electrically insulating organic ligands in CsPbBr 3 NCs hinders efficient charge injection and transportation in light-emitting diodes (LEDs). A common approach to address this issue involves ligand exchange with shorter ligands and precise control of the surface ligand density through additional purification steps. Nevertheless, the practical application of these methods has been hindered by their poor structural integrity and high surface-defect density, which remain a challenge. Our investigation reveals that NOBF 4 treatment effectively replaces native ligands with BF 4 - anions, in which BF 4 - anions are readily coordinated with the positively charged CsPbBr 3 surface metal centers, thereby improving the photoluminescence quantum yield (PLQY) and thermal stability. In particular, the presence of BF 4 - anions coordinated at CsPbBr 3 surfaces efficiently suppresses the pathway of excitons toward thermally activated nonradiative recombination, leading to minimal thermal quenching and superior device performance in green-emitting PeLEDs. Notably, PeLEDs based on CsPbBr 3 NCs with the reconstructed surface via NOBF 4 treatment exhibit an improved current efficiency of 31.12 cd/A and an external quantum efficiency of 11.24%, increased by 2.8 times compared to that of the pristine sample, indicating the enhanced hole-electron injection and transport into the CsPbBr 3 NCs. Therefore, our results highlight the potential of NOBF 4 as a versatile reagent for the ligand exchange and surface passivation of CsPbBr 3 NCs, thereby offering promising prospects for the development of stable, high-performance PeLEDs.

Lead-based halide perovskites have gained significant prominence in recent years in optoelectronics and photovoltaics, owing to their exceptional optoelectronic properties. Nonetheless, the toxicity of lead (Pb) and the stability concern pose obstacles to their potential for future large-scale market development. Herein, stable lead-free Cs 3 Bi 2 I 9 (CBI) films are presented with smooth and compact morphologies synthesized via chemical vapor deposition (CVD), demonstrating their application as an UV photodetector in a self-powered way. The self-powered photodetectors (SPDs) exhibit remarkable characteristics, including a responsivity of 1.57 A W -1 and an impressive specific detectivity of 3.38 × 10 13 Jones under the illumination of 365 nm at zero bias. Furthermore, the SPDs exhibit a nominal decline (≈2.2%) in the photocurrent under constant illumination over 500 h, highlighting its impressive long-term operational stability. Finally, the real-time UV-detection capability of the device is demonstrated by measuring the photocurrent under various conditions, including room light and sunlight at different times. These findings offer a new platform for synthesizing stable and high-quality perovskite films, and SPDs for advancing the development of wearable and portable electronics., (© 2024 Wiley‐VCH GmbH.)

Transition-metal dichalcogenides (TMDs) and metal halide perovskites (MHPs) have been investigated for various applications, owing to their unique physical properties and excellent optoelectronic functionalities. TMD monolayers synthesized via chemical vapor deposition (CVD), which are advantageous for large-area synthesis, exhibit low mobility and prominent hysteresis in the electrical signals of field-effect transistors (FETs) because of their native defects. In this study, we demonstrate an increase in electrical mobility by ∼170 times and reduced hysteresis in the current-bias curves of MoS 2 FETs hybridized with CsPbBr 3 for charge transfer doping, which is implemented via solution-based CsPbBr 3 -nanocluster precipitation on CVD-grown MoS 2 monolayer FETs. Electrons injected from CsPbBr 3 into MoS 2 induce heavy n-doping and heal point defects in the MoS 2 channel layer, thus significantly increasing mobility and reducing hysteresis in the hybrid FETs. Our results provide a foundation for improving the reliability and performance of TMD-based FETs by hybridizing them with solution-based perovskites.

Amorphous metal oxide semiconductor phototransistors (MOTPs) integrated with colloidal quantum dots (QDs) (QD-MOTPs) are promising infrared photodetectors owing to their high photoconductive gain, low off-current level, and high compatibility with pixel circuits. However, to date, the poor mobility of conventional MOTPs, such as indium gallium zinc oxide (IGZO), and the toxicity of lead (Pb)-based QDs, such as lead sulfide and lead selenide, has limited the commercial applications of QD-MOTPs. Herein, an ultrasensitive QD-MOTP fabricated by integrating a high-mobility zinc oxynitride (ZnON)-based MOTP and lead-free indium arsenide (InAs) QDs is demonstrated. A new gradated bandgap structure is introduced in the InAs QD layer that absorbs infrared light, which prevents carriers from moving backward and effectively reduces electron-hole recombination. Chemical, optical, and structural analyses confirm the movement of the photoexcited carriers in the graded band structure. The novel QD-MOTP exhibits an outstanding performance with a responsivity of 1.15 × 10 5 A W -1 and detectivity of 5.32 × 10 16 Jones at a light power density of 2 µW cm -2 under illumination at 905 nm., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

While many deep-learning-based computer-aided detection systems (CAD) have been developed and commercialized for abnormality detection in chest radiographs (CXR), their ability to localize a target abnormality is rarely reported. Localization accuracy is important in terms of model interpretability, which is crucial in clinical settings. Moreover, diagnostic performances are likely to vary depending on thresholds which define an accurate localization. In a multi-center, stand-alone clinical trial using temporal and external validation datasets of 1,050 CXRs, we evaluated localization accuracy, localization-adjusted discrimination, and calibration of a commercially available deep-learning-based CAD for detecting consolidation and pneumothorax. The CAD achieved image-level AUROC (95% CI) of 0.960 (0.945, 0.975), sensitivity of 0.933 (0.899, 0.959), specificity of 0.948 (0.930, 0.963), dice of 0.691 (0.664, 0.718), moderate calibration for consolidation, and image-level AUROC of 0.978 (0.965, 0.991), sensitivity of 0.956 (0.923, 0.978), specificity of 0.996 (0.989, 0.999), dice of 0.798 (0.770, 0.826), moderate calibration for pneumothorax. Diagnostic performances varied substantially when localization accuracy was accounted for but remained high at the minimum threshold of clinical relevance. In a separate trial for diagnostic impact using 461 CXRs, the causal effect of the CAD assistance on clinicians' diagnostic performances was estimated. After adjusting for age, sex, dataset, and abnormality type, the CAD improved clinicians' diagnostic performances on average (OR [95% CI] = 1.73 [1.30, 2.32]; p < 0.001), although the effects varied substantially by clinical backgrounds. The CAD was found to have high stand-alone diagnostic performances and may beneficially impact clinicians' diagnostic performances when used in clinical settings., (© 2022. The Author(s).)

Aims: To investigate anti-inflammatory effects of Lactobacillus reuteri LM1071 in lipopolysaccharides (LPS)-induced inflammation RAW264.7 cells., Methods and Results: To evaluate anti-inflammatory activities of L. reuteri LM1071, LPS-stimulated RAW264.7 cells were used. Gene expression levels of eight immune-associated genes including IL-1β, IL-6 and TNF-α and protein production levels of COX-1 and COX-2 were analysed. Moreover, the production of eicosanoids as important biomarkers for anti-inflammation was determined., Conclusions: The current study demonstrates that L. reuteri LM1071 has anti-inflammatory potential by inhibiting the production of inflammation mediators such as NO, eicosanoids such as PGE1 & PGE2, pro-inflammatory cytokines and COX proteins. It can also enhance the production of inflammatory associated genes such as IL-11, BMP4, LEFTY2 and EET metabolite., Significance and Impact of the Study: Lactobacillus reuteri is one of the crucial bacteria for food fermentation. It can be found in the gastrointestinal system of human and animals. Several studies have shown that L. reuteri has valuable effects on host health. The current study firstly demonstrated that L. reuteri has a beneficial effect on the inflammation containing the variation of eicosanoids (PGE1 and PGE2) which are one of the most important biomarkers and moreover eicosanoid-associated genes as well as proteins (COX-2)., (© 2021 The Society for Applied Microbiology.)

The additional (CH 3 NH 3 ) 2 MnCl 4 phase was observed upon increasing the Mn 2+ dopant concentration, preventing the formation of Mn 2+ -doped CH 3 NH 3 PbCl 3 NCs. We introduce an approach to avoid the formation of an impurity phase by switching the sequence for the addition of MnCl 2 in the crystal growth process.

Histamine releasing factor/translationally controlled tumor protein (HRF/TCTP) stimulates cancer progression and allergic responses, but the role of HRF/TCTP in rheumatoid arthritis (RA) remains undefined. In this study, we explored the pathogenic significance of HRF/TCTP and evaluated the therapeutic effects of HRF/TCTP blockade in RA. HRF/TCTP transgenic (TG) and knockdown (KD) mice with collagen-induced arthritis (CIA) were used to determine the experimental phenotypes of RA. HRF/TCTP levels in the sera of RA patients were measured and compared to those from patients with osteoarthritis (OA), ankylosing spondylitis, Behçet's disease, and healthy controls. HRF/TCTP expression was also assessed in the synovium and fibroblast-like synoviocytes (FLSs) obtained from RA or OA patients. Finally, we assessed the effects of HRF/TCTP and dimerized HRF/TCTP-binding peptide-2 (dTBP2), an HRF/TCTP inhibitor, in RA-FLSs and CIA mice. Our clinical, radiological, histological, and biochemical analyses indicate that inflammatory responses and joint destruction were increased in HRF/TCTP TG mice and decreased in KD mice compared to wild-type littermates. HRF/TCTP levels in the sera, synovial fluid, synovium, and FLSs were higher in patients with RA than in control groups. Serum levels of HRF/TCTP correlated well with RA disease activity. The tumor-like aggressiveness of RA-FLSs was exacerbated by HRF/TCTP stimulation and ameliorated by dTBP2 treatment. dTBP2 exerted protective and therapeutic effects in CIA mice and had no detrimental effects in a murine tuberculosis model. Our results indicate that HRF/TCTP is a novel biomarker and therapeutic target for the diagnosis and treatment of RA.

Lactic acid bacteria are well-known probiotics, conferring several health benefits. In this study, we isolated lactobacilli from human breast milk and identified Lactobacillus reuteri LM1071 (RR-LM1071) using 16S rDNA sequencing. We tested the hemolytic activity, biogenic amine production, and antibiotic susceptibility of this strain to assess its safety. RR-LM1071 was found to be negative for hemolytic activity and biogenic amine production, as well as was measured in susceptible level for antibiotics in the minimal inhibitory concentration (MIC) test. The adhesive properties of RR-LM1071 were higher than those of LGG in HT-29 cells, and showed a greater hydrophobicity than LGG in hexadecane solvent. Under inflammatory conditions, RR-LM1071 suppressed the mRNA expression of IL-6, TNF-α, and IL-4 produced in IL-1β-induced HT-29 cells. Our results suggest that RR-LM1071 is a safe and valuable probiotic that can be used for the treatment of inflammatory bowel disease., Competing Interests: No potential conflict of interest relevant to this article was reported., (© Copyright 2020 Korean Society of Animal Science and Technology.)

In this study, we explored whether the use of Streptococcus thermophilus LM1012 (TL-LM1012) as a safe probiotic exerts hepatoprotective effects by suppressing oxidative stress and inflammation in vitro and alleviating aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) production in vivo . In a series of safety tests, TL-LM1012 was found to have a negative response to hemolysis and biogenic amines, as well as susceptibility to antibiotics. TL-LM1012 protected cell viability and suppressed cytotoxicity by inhibiting oxidative stress and induced heme oxygenase-1 and superoxide dismutase activity in a dose-dependent manner in diesel exhaust particulate matter (DEPM)-treated HepG2 cells. Moreover, proinflammatory cytokines, including tumor necrosis factor- α , interleukin (IL)-6, and IL-1 β , were suppressed in DEPM-treated splenocytes. In DEPM-treated mice, oral administration of TL-LM1012 regulated AST, ALT, and LDH production in the serum after 14 days of treatment. These findings indicate that TL-LM1012, a safe probiotic, provides a potent preventive or therapeutic effect against liver disease caused by air pollution.

Tunable diode laser absorption spectroscopy (TDLAS) technology is a developing method for temperature and species concentration measurements with the features of non-contact, high precision, high sensitivity, etc. The difficulty of two-dimensional (2D) temperature measurement in actual combustors has not yet been solved because of pressure broadening of absorption spectra, optical accessibility, etc. In this study, the combination of computed tomography (CT) and TDLAS with a wide scanning laser at 1335-1375 nm has been applied to a combustor for 2D temperature measurement in high temperature of 300-2000 K and high pressure of 0.1-2.5 MPa condition. An external cavity type laser diode with wide wavelength range scanning at 1335-1375 nm was used to evaluate the broadened H 2 O absorption spectra due to the high-temperature and high-pressure effect. The spectroscopic database in high temperature of 300-2000 K and high pressure of 0.1-5.0 MPa condition has been revised to improve the accuracy for temperature quantitative analysis. CT reconstruction accuracy was also evaluated in different cases, which presented the consistent temperature distribution between CT reconstruction and assumed distributions. The spatial and temporal distributions of temperature in the high-temperature and high-pressure combustor were measured successfully by CT-TDLAS using the revised spectroscopic database.

The present study investigated the immunomodulatory activity and associated mechanisms of heat-treated Lactobacillus plantarum LM1004 (HT-LM1004) in a cyclophosphamide (CTX)-induced mouse model of immunosuppression. HT-LM1004 induced phagocytic activity and nitric oxide production in RAW264.7 macrophages and stimulated the release of tumor necrosis factor (TNF)- α , interferon (IFN)- γ , interleukin (IL)-2, and IL-12p70. In mice with CTX-induced immunosuppression, oral HT-LM1004 administration restored thymus and spleen indices, including spleen weight. Consistent with the in vitro results, HT-LM1004 increased TNF- α , IFN- γ , IL-2, and IL-12p70 levels in mice after 14 days of treatment and enhanced the natural killer (NK) cell activity of splenocytes from mice with CTX-induced immunosuppression against YAC-1 lymphoma cells. The method of HT-LM1004 generation influenced this activity: L. plantarum LM1004 grown in a membrane bioreactor, which reduced the size of the cells to <1.0 μm through physical stress (micronization), promoted NK cell cytotoxicity to a greater extent than LM1004 subjected to heat treatment alone. These findings indicate that HT-LM1004 without or with micronization can reverse CTX-induced immunosuppression without adverse side effects by potentiating NK cell function.

Organolead halide perovskite nanocrystals (NCs) have emerged as promising materials for various optoelectronic applications. However, their practical applications have been limited due to low structural integrity and poor luminescence stability associated with fast attachment-detachment dynamics of surface capping molecules during postprocessing. At present, a framework for understanding how the functional additives interact with surface moieties of organolead halide perovskites is not available. Methylammonium lead bromide NCs without surfactants on their surface provide an ideal system to investigate the direct interactions of the perovskite with functional molecules. When the oleic acid is used in a combination with n -octylamine, its contribution to surface passivation is significantly increased by protonating the alkyl amine to the corresponding ammonium ion. Our results demonstrate that the Br vacancies at the nonpassivated surface result in a reduction of Pb 2+ to Pb 0 by trapping electrons generated from the exciton dissociation, which provides a main pathway for exciton trapping.

The purpose of this study is to investigate the effect of TSAHC [4'-(p-toluenesulfonylamido)-4-hydroxychalcone] in K/BxN serum transfer arthritis model and fibroblast-like synoviocytes of rheumatoid arthritis (RA-FLS). In in vivo experiments, TSAHC attenuated the incidence and severity of arthritis in comparison with the vehicle group. Histological findings showed that TSAHC decreased the inflammation, bone erosion, cartilage damage, and osteoclasts activity in the ankle. Furthermore, we confirmed by biochemical analysis that the observations were associated with the decreased expression of proinflammatory cytokines, matrix metalloproteinases (MMPs), and RANKL in serum and ankle. In in vitro experiments, TSAHC induced apoptosis, while it significantly suppressed tumor necrosis factor-α (TNF-α)-induced cell proliferation in RA-FLS. Moreover, TSAHC inhibited mRNA expression of TNF-α-induced interleukin (IL)-6, MMP-1, MMP-3, and MMP-13. Evaluation of signaling events showed that TSAHC inhibited the translocation and transcriptional activity of nuclear factor-kappa B (NF-κB) by regulating phosphorylated-IκB-α (p-IκB-α) and IκB-α in TNF-α-induced RA-FLS. Our results suggest that TSAHC inhibits experimental arthritis in mice and suppresses TNF-α-induced RA-FLS activities via NF-κB pathway. Therefore, TSAHC may have therapeutic potential for the treatment of RA.

We determined and annotated the whole mtDNA genome of the roe deer Capreolus pygargus tianschanicus in Korea. The complete mitogenome is a circular molecule of 16,357 bp in length, including 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes, and 2 non-coding regions (L-strand replication origin and control region). The mitogenome is AT-biased, with a nucleotide composition of 33.5% A, 30.0% T, 23.2% C, and 13.4% G. The phylogenetic analysis revealed the Korean roe deer C. p. tianschanicus is placed within the genus Caprelous clade, which has the water deer of the genus Hydropotes as sister clade., Competing Interests: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper., (© 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

The mitogenome of the Asian badger Meles leucurus from Korea is a circular molecule of 16,529 bp, consisting of a control region and a conserved set of 37 genes containing 13 protein-coding genes (PCGs), 22 tRNA genes, and two rRNA genes ( 12S rRNA and 16S rRNA ). The mitogenome of M. leucurus is AT-biased, with a nucleotide composition of 33.1% A, 27.9% T, 25.4% C, and 13.5% G. The phylogenetic analysis revealed that the badger M. leucurus from Korea is well grouped with that from China, forming a sister clade to M. meles from Japan., Competing Interests: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper., (© 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.)

Wild mouse feces can disseminate zoonotic microorganisms throughout a farm, which is a great threat to human health and can lead to economic loss through contaminated agricultural produce. To assess the microbial communities, especially fecal coliform bacteria, we used two methods. First, we isolated bacterial colonies onto the common media LB (lactose broth) agar, TSA (tryptic soy agar), and MRS (de Man, Rogosa, and Sharpe) agar, and then randomly select colonies from each plate and stocked them to the mother plate for genomic DNA isolation. Second, we analyzed bacterial colonies using the 16S rRNA gene molecular diagnostic method. Based on bacterial cultures and bacterial 16S rRNA gene markers, we detected four different bacterial species (Bacillus amyloliquefaciens, Escherichia coli, Staphylococcus xylosus, and Serratia liquefaciens) from fecal coliforms of the striped field mouse Apodemus agrarius and A. peninsulae in agricultural areas in South Korea. These results could help us to better understand the pathogen reservoirs of mice and initiate some preventive measures to mitigate the microbial risks associated with mouse fecal matter in agricultural production areas.

We sequenced and characterized a complete mitogenome (KP671850) of the Chinese Apodemus peninsulae and compared it with a previously published mitogenome of the Korean A. peninsulae (NC016060). The total length of the Chinese A. peninsulae mitogenome is 16,457 bp. The mitogenome consists of 13 protein-coding genes (PCGs), two rRNA (12S rRNA and 16S rRNA) genes, 22 tRNA genes, and one D-loop region. The most common start codon was ATG, used in the nine PCGs for initiation. The mitogenomes of Chinese and Korean A. peninsulae showed 98.9% sequence similarity. The intra-/interspecific phylogeny of the Chinese A. peninsulae revealed that the Chinese A. peninsulae was well grouped with the Korean A. peninsulae. The clade of A. peninsulae was sister to that of Apodemus agrarius, Apodemus chejuensis, and Apodemus chevrieri.

The type III histone deacetylase silent information regulator 1 (SIRT1) is an enzyme that is critical for the modulation of immune and inflammatory responses. However, the data on its role in rheumatoid arthritis (RA) are limited and controversial. To better understand how SIRT1 regulates adaptive immune responses in RA, we evaluated collagen-induced arthritis (CIA) in myeloid cell-specific SIRT1 knockout (mSIRT1 KO) and wild-type (WT) mice. Arthritis severity was gauged on the basis of clinical, radiographic and pathologic scores. Compared with their WT counterparts, the mSIRT1 KO mice exhibited less severe arthritis, which was less destructive to the joints. The expression levels of inflammatory cytokines, matrix metalloproteinases and ROR-γT were also reduced in the mSIRT1 KO mice compared with the WT mice and were paralleled by reductions in the numbers of Th1 and Th17 cells and CD80- or CD86-positive dendritic cells (DCs). In addition, impaired DC maturation and decreases in the Th1/Th17 immune response were observed in the mSIRT1 KO mice. T-cell proliferation was also investigated in co-cultures with antigen-pulsed DCs. In the co-cultures, the DCs from the mSIRT1 KO mice showed decreases in T-cell proliferation and the Th1/Th17 immune response. In this study, myeloid cell-specific deletion of SIRT1 appeared to suppress CIA by modulating DC maturation. Thus, a careful investigation of DC-specific SIRT1 downregulation is needed to gauge the therapeutic utility of agents targeting SIRT1 in RA.

It is suggested that n-3 polyunsaturated fatty acids (PUFAs) can be used in the preventive or therapeutic management of rheumatoid arthritis (RA); however, controversial results have been reported. Here, we examined the effects of a decrease in the n-6/n-3 PUFA ratio on RA using fat-1 transgenic mice. First, we tested whether fat-1 expression modulated signaling pathways in fibroblast-like synoviocytes (FLSs) stimulated with tumor necrosis factor α (TNF-α). TNF-α activated p38 mitogen-activated protein kinase and increased phosphorylation of the signal transducer and activator of transcription 3 in wild type (WT) FLSs but not in fat-1 FLSs. Arthritis was induced by injection of K/BxN serum. Based on clinical scores, ankle thickness and pathological severity, we showed that WT mice developed clinically overt arthritis, whereas fat-1 mice showed attenuated arthritis. Moreover, fat-1 mice exhibited down-regulated local and systemic levels of inflammatory cytokines. Lastly, bone marrow-derived macrophages (BMMs) of WT mice differentiated into tartrate-resistant acid phosphatase-positive multinucleated osteoclasts, whereas the osteoclastogenenic process was suppressed in BMMs of fat-1 mice. The endogenous conversion of n-6 to n-3 PUFAs via fat-1 plays a key role in attenuation of RA; therefore, dietary supplementation of n-3 PUFAs may have therapeutic potential for the management of RA., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Objective: Demonstrate that incorporating domain knowledge into feature selection methods helps identify interpretable features with predictive capability comparable to a state-of-the-art classifier., Methods: Two feature selection methods, one using a genetic algorithm (GA) the other a L(1)-norm support vector machine (SVM), were investigated on three real-world biomedical magnetic resonance (MR) spectral datasets of increasing difficulty. Consensus sets of the feature sets obtained by the two methods were also assessed., Results and Conclusions: Features identified independently by the two methods and by their consensus, determine class-discriminatory groups or individual features, whose predictive power compares favorably with that of a state-of-the-art classifier. Furthermore, the identified feature signatures form stable groupings at definite spectral positions, hence are readily interpretable. This is a useful and important practical result for generating hypothesis for the domain expert.

Although biochemical properties of 2-Cys peroxiredoxins (Prxs) have been extensively studied, their real physiological functions in higher eukaryotic cells remain obscure and certainly warrant further study. Here we demonstrated that human (h) PrxII, a cytosolic isotype of human 2-Cys Prx, has dual functions as a peroxidase and a molecular chaperone, and that these different functions are closely associated with its adoption of distinct protein structures. Upon exposure to oxidative stress, hPrxII assumes a high molecular weight complex structure that has a highly efficient chaperone function. However, the subsequent removal of stressors induces the dissociation of this protein structure into low molecular weight proteins and triggers a chaperone-to-peroxidase functional switch. The formation of a high molecular weight hPrxII complex depends on the hyperoxidation of its N-terminal peroxidatic Cys residue as well as on its C-terminal domain, which contains a "YF motif" that is exclusively found in eukaryotic 2-Cys Prxs. A C-terminally truncated hPrxII exists as low and oligomeric protein species and does not respond to oxidative stress. Moreover, this C-terminal deletion of hPrxII converted it from an oxidation-sensitive to a hyperoxidation-resistant form of peroxidase. When functioning as a chaperone, hPrxII protects HeLa cells from H(2)O(2)-induced cell death, as measured by a terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling assay and fluorescence-activated cell sorting analysis.