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1.
BMC Cancer ; 22(1): 868, 2022 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-35945555

RESUMEN

BACKGROUND: Preoperative neoadjuvant chemoradiation (nCRT) has been the standard treatment for locally advanced rectal cancer. Serum biomarkers to stratify patients with respect to prognosis and response to nCRT are needed due to the diverse response to the therapy. METHODS: Thirteen paired pre- and post-nCRT sera from rectal cancer patients were analyzed by isobaric tags for relative and absolute quantitation (iTRAQ) method. Twenty-five proteins were selected for validation by parallel reaction monitoring (PRM) in ninety-one patients. RESULTS: Totally, 310 proteins were identified and quantified in sera samples. Reactome pathway analysis showed that the immune activation-related pathways were enriched in response to nCRT. Twenty-five proteins were selected for further validation. PRM result showed that the level of PZP was higher in pathological complete response (pCR) patients than non-pCR patients. The Random Forest algorithm identified a prediction model composed of 10 protein markers, which allowed discrimination between pCR patients and non-pCR patients (area under the curve (AUC) = 0.886 on testing set). Higher HEP2 and GELS or lower S10A8 in baseline sera were associated with better prognosis. Higher APOA1 in post nCRT sera was associated with better disease-free survival (DFS). CONCLUSIONS: We identified and confirmed a 10-protein panel for nCRT response prediction and four potential biomarkers HEP2, GELS, S10A8 and APOA1 for prognosis of rectal cancer based on iTRAQ-based comparative proteomics screening and PRM-based targeted proteomic validation.


Asunto(s)
Terapia Neoadyuvante , Neoplasias del Recto , Biomarcadores , Quimioradioterapia , Geles , Humanos , Proteómica/métodos , Neoplasias del Recto/patología , Resultado del Tratamiento
2.
Entropy (Basel) ; 24(7)2022 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-35885233

RESUMEN

Semantic-rich speech emotion recognition has a high degree of popularity in a range of areas. Speech emotion recognition aims to recognize human emotional states from utterances containing both acoustic and linguistic information. Since both textual and audio patterns play essential roles in speech emotion recognition (SER) tasks, various works have proposed novel modality fusing methods to exploit text and audio signals effectively. However, most of the high performance of existing models is dependent on a great number of learnable parameters, and they can only work well on data with fixed length. Therefore, minimizing computational overhead and improving generalization to unseen data with various lengths while maintaining a certain level of recognition accuracy is an urgent application problem. In this paper, we propose LGCCT, a light gated and crossed complementation transformer for multimodal speech emotion recognition. First, our model is capable of fusing modality information efficiently. Specifically, the acoustic features are extracted by CNN-BiLSTM while the textual features are extracted by BiLSTM. The modality-fused representation is then generated by the cross-attention module. We apply the gate-control mechanism to achieve the balanced integration of the original modality representation and the modality-fused representation. Second, the degree of attention focus can be considered, as the uncertainty and the entropy of the same token should converge to the same value independent of the length. To improve the generalization of the model to various testing-sequence lengths, we adopt the length-scaled dot product to calculate the attention score, which can be interpreted from a theoretical view of entropy. The operation of the length-scaled dot product is cheap but effective. Experiments are conducted on the benchmark dataset CMU-MOSEI. Compared to the baseline models, our model achieves an 81.0% F1 score with only 0.432 M parameters, showing an improvement in the balance between performance and the number of parameters. Moreover, the ablation study signifies the effectiveness of our model and its scalability to various input-sequence lengths, wherein the relative improvement is almost 20% of the baseline without a length-scaled dot product.

3.
Proc Natl Acad Sci U S A ; 115(51): 13087-13092, 2018 12 18.
Artículo en Inglés | MEDLINE | ID: mdl-30514821

RESUMEN

Seneca Valley virus (SVV) is an oncolytic picornavirus with selective tropism for neuroendocrine cancers. SVV mediates cell entry by attachment to the receptor anthrax toxin receptor 1 (ANTXR1). Here we determine atomic structures of mature SVV particles alone and in complex with ANTXR1 in both neutral and acidic conditions, as well as empty "spent" particles in complex with ANTXR1 in acidic conditions by cryoelectron microscopy. SVV engages ANTXR1 mainly by the VP2 DF and VP1 CD loops, leading to structural changes in the VP1 GH loop and VP3 GH loop, which attenuate interprotomer interactions and destabilize the capsid assembly. Despite lying on the edge of the attachment site, VP2 D146 interacts with the metal ion in ANTXR1 and is required for cell entry. Though the individual substitution of most interacting residues abolishes receptor binding and virus propagation, a serine-to-alanine mutation at VP2 S177 significantly increases SVV proliferation. Acidification of the SVV-ANTXR1 complex results in a major reconfiguration of the pentameric capsid assemblies, which rotate ∼20° around the icosahedral fivefold axes to form a previously uncharacterized spent particle resembling a potential uncoating intermediate with remarkable perforations at both two- and threefold axes. These structures provide high-resolution snapshots of SVV entry, highlighting opportunities for anticancer therapeutic optimization.


Asunto(s)
Proteínas de la Cápside/metabolismo , Proteínas de Neoplasias/metabolismo , Picornaviridae/fisiología , Receptores de Superficie Celular/metabolismo , Desencapsidación Viral/fisiología , Proteínas de la Cápside/química , Proteínas de la Cápside/genética , Microscopía por Crioelectrón , Cristalografía por Rayos X , Humanos , Proteínas de Microfilamentos , Modelos Moleculares , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Unión Proteica , Conformación Proteica , Receptores de Superficie Celular/química , Receptores de Superficie Celular/genética
4.
Plant Dis ; 2021 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-34132594

RESUMEN

Kiwifruits (Actinidia ssp.), known as "King of vitamin C", have been wildly cultivated. In August 2020, about 15% of A. deliciosa (cv. Xuxiang) and A. macrosperma (rootstock) plants displayed symptoms typical of root rot at a farm in Hefei (117°25'E, 31°86'N), Anhui Province of China (Fig.1 a-b). Symptoms first appeared at the root and stem junction which were covered by cottony white mycelium during warm and humid summer. Then, the infected tissues were rotted, and subsequently the whole plant withered. Tan to brown sclerotia were observed on the basal stem epidermis and soil surface surrounding the stem (Fig.1 c-d). Infected plant tissues and sclerotia were collected for isolating the fungal pathogen. The samples were surface sterilized in 70% alcohol for 30 s, followed by 2% sodium hypochlorite for 3 min, washed five times with sterile double-distilled water (ddH2O), dried, placed on potato dextrose agar, and incubated at 25 °C in the dark. In total, twelve fungal isolates were obtained. The mycelia of all the isolates were white with a fluffy appearance (Fig.1 e). Sclerotia formed after 7 days were initially white (Fig.1 f) and gradually turned to dark brown (Fig.1 g) measuring 0.67 to 2.03 mm in diameter (mean = 1.367 ± 0.16 mm; n = 30). Hyphae were hyaline, septate. Some cells possessed multiple nuclei (Fig.1 h) and clamp connections (Fig.1 i). No spores were observed. For species-level identification, ITS1/ITS4 and EF1-983F/EF1-2218R primers were used to amplify the internal transcribed spacer regions (ITS) and translation elongation factor-1 alpha regions (TEF-1α), respectively (White et al. 1990; Rehner & Buckley 2005). Based on ITS and TEF-1α sequence analyses, all 12 isolates were categorized into two groups, group one including isolates NC-1 and NC-6~10 and group two containing NC-2~5 and NC-11~12. The length of ITS sequences for NC-1 (MW311079) was 684bp and 99% to 100% similar to Athelia rolfsii (MN610007.1, MN258360.1). Similarly, ITS sequences for NC-2 (MW311080) were 99% to 100% similar to A. rolfsii (MH858139.1; MN872304.1). Also, TEF-1α sequences of NC-1 (MW322687) and NC-2 (MW322688) were 96% to 99% similar to sequences of A. rolfsii (MN702794.1, GU187681.1, MN702789.1). Based on morphology and phylogenetic analyses (Fig.1 j&k), the isolates NC-1 and NC-2 were identified as Athelia rolfsii (anamorph Sclerotium rolfsii) (Mordue. 1974; Punja. 1985). To fulfill Koch's postulates, ten sclerotia of NC-1 were incorporated into the soil near stems of healthy Xuxiang plants (Fig.2 a). Similar treatments were also used for plants of A. macrosperma or A. arguta (Fig.2 g&m). Each control group had the same number of plants (n=3) for inoculating with ddH2O. The plants were kept in an incubator with a relative humidity of 80% and temperature of 28°C with 16/8 hours light/dark photoperiod. After twenty days, the pathogen-inoculated plants developed similar symptoms of root rot observed in the field (Fig.2 b-d, h-j, n-o). Similarly, four days after inoculation with sclerotia, leaves developed water-soaked lesions (Fig.2 e, k&p). No significant difference in pathogenicity was observed between NC-1 and NC-2. Non-inoculated control plants remained disease-free (Fig.2 f, l&q). The pathogenicity experiments were repeated three times. The pathogen was re-isolated from infected tissues and sclerotia, and isolates were confirmed as A. rolfsii by the ITS sequences. A. rolfsii has been reported to cause root rot in kiwifruit in the USA (Raabe. 1988). To our knowledge, this is the first report A. rolfsii causing root rot on kiwifruits in China.

5.
Electrophoresis ; 41(7-8): 621-629, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31845347

RESUMEN

We examine the electrophoresis of spherical particles in microfluidic devices made of alternating wells and narrow channels, including a system previously used to separate DNA molecules. Our computer simulations predict that such systems can be used to separate spherical particles of different sizes that share the same free-solution mobility. Interestingly, the electrophoretic velocity shows an inversion as the field intensity is increased: while small particles have higher velocities at low field, the situation is reversed at high fields with the larger particles then moving faster. The resulting nonlinearity suggests that asymmetric pulsed electric fields could be used to build separation ratchets: particles then have a net size-dependent velocity in the presence of a zero-mean external field. Exploiting the inversion mentioned above, we show how to design pulsed field sequences that make particles move against the mean field (an example of negative mobility). Finally, we demonstrate that it is possible to use pulsed fields to make particles of different sizes move in opposite directions, even though their charge have the same sign.


Asunto(s)
Electroforesis/métodos , Técnicas Analíticas Microfluídicas/métodos , Modelos Químicos , Simulación por Computador , Tamaño de la Partícula
6.
Plant Dis ; 2020 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-33373285

RESUMEN

Kiwifruit (Actinidia spp.) has been extensively cultivated (about 165728 hm2 recorded in 2017) and postharvest rot diseases have caused severe losses to the industry in China. In October 2019, fruit (n=60) of cv. Xuxiang (A. deliciosa) were obtained from a farm (120.62°E, 28.92°N) in Pan'an county, Zhejiang province, China. After the fruit were stored at 24 °C and 70% relative humidity (RH) for 10 days, soft lesions (20 to 45 mm in diameter) with sour odor and white mycelium were observed on ~20% of fruits (Fig. 1a). Irregular lesions were produced on the mesocarp were off-white to pale yellow (Fig. 1b). Small pieces (4×4 mm) from the lesion margins were excised, surface disinfested in 70% ethanol for 1 min and 10% NaOCl for 5 min, washed, dried, plated on PDA and incubated at 25°C for 7 days. A total of seven pure fungal colonies were obtained, and included two isolates of Nigrospora sphaerica (Li et al. 2018) and five unknown isolates. The remaining five isolates produced thin, flat, white to cream and feathery (Fig.1c & d) mycelium. Hyphae were hyaline, septate, dichotomously branched and break into chains of subglobose to cylindrical arthrospores (Fig. 1e, f & g). The dimension of arthrospores varies from 4.11 to 12.55 × 2.54 to 5.84 µm (n=100) (Fig. 1h). To identify these isolates to species, the internal transcribed spacer (ITS), 26S rDNA, translation elongation factor-1 alpha regions (TEF-1α) were amplified and sequenced (Ma et al. 2018). Sequence analysis indicated no differences in 26S rDNA and TEF-1α, but the ITS that placed the isolates into two phylogenetic groups. Isolates gx2-2 and gx3-1 representing group one (gx2-1, gx2-2, and gx5-1) and group two (gx3-1 and gx4-1) respectively, were employed for further studies. Based on BLASTn analysis, ITS sequences for gx2-2 (MT946912) and gx3-1(MT946913) isolates had 100% and 98.40% identity respectively, with G. candidum accessions KY103452 and KY103455. Nevertheless, 26S rDNA sequences (MT981194; MT981195) showed 99.82% identity with G. candidum accessions JN974268 and KF112070. Consistently, the TEF-1α (MT981184; MT981185) had 100% identity with G. candidum accession MT346370. Phylogenetic trees were constructed using the Neighbor-Joining method with a dataset of ITS (Fig. 2a) and 26S rDNA sequences (Fig. 2b), respectively. Based on morphology and phylogenetic analysis, the pathogens gx2-2 and gx3-1 were identified as Geotrichum candidum (De Hoog et al. 1986). To determine pathogenicity, healthy and mature kiwis cv. Xuxiang were surface sterilized. Wounded and unwounded fruits were inoculated with each conidial suspension derived from the two isolates (107 conidia/mL, 30 µL for each fruit) and stored at 24 °C under 90% RH. Control fruit were treated with sterile distilled water. Each treatment consisted of 20 fruit was evaluated daily for 10 days and repeated once. The symptom was mimic the naturally infected fruits (Fig.1i, m & n). The pathogen could develop into inner pericarp after 7 days while cv. Jinyan (A. chinensis) was used as host (Fig. 1k & l). However, control group remained disease-free (Fig. 1j, o & p). The fungus could penetrate into fruit peel and produce spores that were visualized by scanning electron microscope (Fig.1q & r). For both isolates, the incidence of wounded fruit were 100%, and the incidence of unwounded fruit was 80%. The fungi were re-isolated from diseased tissues and re-identified as G. candidum based on morphology and sequences analyses. G. candidum causes sour rot on many hosts and similar symptom have been previously reported in other regions(Pennycook et al.1989; Horita et al. 2016; Ma, et al. 2018; Zhang et al. 2018; Khan et al. 2019; Halfeld-Vieira et al. 2020), but this is the first report of G. candidum on kiwifruit in China.

7.
Reprod Fertil Dev ; 31(2): 357-365, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30196805

RESUMEN

Aberrant DNA methylation reduces the developmental competence of mammalian somatic cell nuclear transfer (SCNT) embryos. Thus, hypomethylation-associated drugs are beneficial for improving reprogramming efficiency. Therefore, in the present study we investigated the effect of zebularine, a relatively novel DNA methyltransferase inhibitor, on the developmental potential of ovine SCNT embryos. First, reduced overall DNA methylation patterns and gene-specific DNA methylation levels at the promoter regions of pluripotency genes (octamer-binding transcription factor 4 (Oct4), SRY (sex determining region Y)-box 2 (Sox2) and Nanog) were found in zebularine-treated cumulus cells. In addition, the DNA methylation levels in SCNT embryos derived from zebularine-treated cumulus cells were significantly reduced at the 2-, 4-, 8-cell, and blastocyst stages compared with their corresponding controls (P<0.05). The blastocyst rate was significantly improved in SCNT embryos reconstructed by the cumulus donor cells treated with 5nM zebularine for 12h compared with the control group (25.4±1.6 vs 11.8±1.7%, P<0.05). Moreover, the abundance of Oct4 and Sox2 mRNA was significantly increased during the preimplantation stages after zebularine treatment (P<0.05). In conclusion, the results indicate that, in an ovine model, zebularine decreases overall DNA methylation levels in donor cumulus cells and reconstructed embryos, downregulates the DNA methylation profile in the promoter region of pluripotency genes in donor cells and ultimately elevates the expression of pluripotency genes in the reconstructed embryos, which can lead to improved development of SCNT embryos.


Asunto(s)
Reprogramación Celular/efectos de los fármacos , Citidina/análogos & derivados , Metilación de ADN/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Metiltransferasas/antagonistas & inhibidores , Animales , Citidina/farmacología , Femenino , Proteína Homeótica Nanog/genética , Proteína Homeótica Nanog/metabolismo , Técnicas de Transferencia Nuclear , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Regiones Promotoras Genéticas , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Ovinos
8.
Insects ; 15(5)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38786918

RESUMEN

Cuticle proteins (CPs) constitute a multifunctional family; however, the physiological role of Cuticle Protein 3-like (CP3L) in Heortia vitessoides Moore remains largely unclear. In this study, we cloned the HvCP3L gene from the transcriptional library of Heortia vitessoides Moore. RT-qPCR results revealed that HvCP3L exhibited high expression levels during the larval stage of Heortia vitessoides Moore, particularly at the L5D1 stage, observed in both larval and adult heads. Through RNA interference, we successfully silenced the HvCP3L gene, resulting in a significant reduction in the survival rate of Heortia vitessoides Moore, with the survival rate from larvae to adults plummeting to a mere 17.7%, accompanied by phenotypic abnormalities. Additionally, we observed that the knockdown of HvCP3L led to the inhibition of genes in the chitin pathway. Following exposure to methoxyfenozide stress, the HvCP3L gene exhibited significant overexpression, coinciding with phenotypic abnormalities. These findings underscore the pivotal role of HvCP3L in the growth and development of Heortia vitessoides Moore.

9.
Front Cell Dev Biol ; 12: 1435241, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39050894

RESUMEN

Introduction: Root dentin formation is an important process in tooth development. We tried to identify potential genes that regulate root dentin formation which could be potentially used for the regeneration and repair of defective or damaged dental roots. Methods: Tissues harvested from the labial and lingual sides of mouse incisors were used for microarray analysis. Gene ontology (GO) analysis of differentially expressed genes indicated the critical role of extracellular matrix in the discrepancy of dentin formation between root and crown, for which hemicentin-1 (Hmcn1) was selected as the target gene. Single-cell RNA sequencing analysis the expression pattern of Hmcn1 at different developmental stages in mouse molars. The spatiotemporal expression of HMCN1 in mouse incisors and molars was detected by immunohistochemical staining. The functions of HMCN1 in human dental pulp cells, including proliferation, differentiation and migration, were examined in vitro by CCK8 assay, BrdU assay, wound-healing assay, ALP staining and alizarin red staining, respectively. Results: It was showed that HMCN1 expression was more pronounced in papilla-pulp on the root than crown side in mouse incisors and molars. In vitro experiments presented inhibited dentinogenesis and migration after HMCN1-knockdown in human dental pulp cells, while there was no significant difference in proliferation between the HMCN1-knockdown group and control group. Discussion: These results indicated that HMCN1 plays an important role in dentinogenesis and migration of pulp cells, contributing to root dentin formation.

10.
Adv Sci (Weinh) ; 11(18): e2308237, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38430536

RESUMEN

The key challenge in cancer treatment is prevention of metastatic disease which is therapeutically resistant and carries poor prognoses necessitating efficacious prophylactic approaches that prevent metastasis and recurrence. It is previously demonstrated that cowpea mosaic virus (CPMV) induces durable antitumor responses when used in situ, i.e., intratumoral injection. As a new direction, it is showed that CPMV demonstrates widespread effectiveness as an immunoprophylactic agent - potent efficacy is demonstrated in four metastatic models of colon, ovarian, melanoma, and breast cancer. Systemic administration of CPMV stimulates the innate immune system, enabling attack of cancer cells; processing of the cancer cells and associated antigens leads to systemic, durable, and adaptive antitumor immunity. Overall, CPMV demonstrated broad efficacy as an immunoprophylactic agent in the rejection of metastatic cancer.


Asunto(s)
Comovirus , Animales , Ratones , Femenino , Metástasis de la Neoplasia/prevención & control , Humanos , Línea Celular Tumoral , Modelos Animales de Enfermedad
11.
Front Microbiol ; 15: 1402319, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38808277

RESUMEN

The toxin-antitoxin (TA) system plays a key role in bacteria escaping antibiotic stress with persistence, however, the mechanisms by which persistence is controlled remain poorly understood. Weissella cibaria, a novel probiotic, can enters a persistent state upon encountering ciprofloxacin stress. Conversely, it resumes from the persistence when ciprofloxacin stress is relieved or removed. Here, it was found that PemIK TA system played a role in transitioning between these two states. And the PemIK was consisted of PemK, an endonuclease toxic to mRNA, and antitoxin PemI which neutralized its toxicity. The PemK specifically cleaved the U↓AUU in mRNA encoding enzymes involved in glycolysis, TCA cycle and respiratory chain pathways. This cleavage event subsequently disrupted the crucial cellular processes such as hydrogen transfer, electron transfer, NADH and FADH2 synthesis, ultimately leading to a decrease in ATP levels and an increase in membrane depolarization and persister frequency. Notably, Arg24 was a critical active residue for PemK, its mutation significantly reduced the mRNA cleavage activity and the adverse effects on metabolism. These insights provided a clue to comprehensively understand the mechanism by which PemIK induced the persistence of W. cibaria to escape ciprofloxacin stress, thereby highlighting another novel aspect PemIK respond for antibiotic stress.

12.
Mater Horiz ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38842068

RESUMEN

Intramolecular exciplex systems featuring thermally activated delayed fluorescence (TADF) have garnered significant attention in the realm of organic light-emitting diodes (OLEDs). Nonetheless, the occurrence of organic sandwich intramolecular exciplexes remains rare due to structural limitations and synthetic challenges. Herein, we present a novel rigid acceptor-donor-acceptor (A-D-A) sandwich complex, dSFQP, characterized by two sp3 C-locking moieties. This compound exhibits TADF characteristics facilitated by a multiple through-space charge-transfer process. X-ray crystallographic analysis confirms the distinctive sandwich configuration. The parallel spatial arrangement and minimized A-D-A configuration enhance electronic interactions, resulting in a high photoluminescence quantum yield, rapid reverse intersystem crossing rate, and sluggish nonradiative decay rate. OLEDs employing dSFQP as the dopant achieve a maximum external quantum efficiency (EQE) of 28.5% with a low efficiency roll-off of merely 2.8% at 1000 cd m-2. Even at a high brightness of 10 000 cd m-2, the EQE remains notably high at 17.5%. Our current results provide an effective way to further innovate the design of new organic charge-transfer complexes.

13.
Chem Asian J ; : e202400679, 2024 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-39073242

RESUMEN

Despite the rapid development of thermally activated delayed fluorescent (TADF) materials, developing organic light-emitting diodes (OLEDs) with small efficiency roll-off remains a formidable challenge. Herein, we have designed a TADF molecule (mClSFO) based on the spiro fluorene skeleton. The highly twisted structure and multiple charge-transfer channels effectively suppress aggregation-caused quenching (ACQ) and endow mClSFO with excellent exciton dynamic properties to reduce efficiency roll-off. Fast radiative rate (kr) and rapid reverse intersystem crossing (RISC) rate (kRISC) of 1.6 × 107 s-1 and 1.07 × 106 s-1, respectively, are obtained in mClSFO. As a result, OLEDs based on mClSFO obtain impressive maximum external quantum efficiency (EQEmax) exceeding 20% across a wide doping concentration range of 10-60 wt%. 30 wt% doped OLED exhibits an EQEmax of 23.1% with a small efficiency roll-off, maintaining an EQE of 18.6% at 1000 cd m-2. The small efficiency roll-off and low concentration dependence observed in the TADF emitter underscore its significant potential.

14.
ACS Appl Mater Interfaces ; 16(13): 16563-16572, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38507218

RESUMEN

In account of the energy gap law, the development of efficient narrow-band gap thermally activated delayed fluorescence (TADF) materials remains a major challenge for the application of organic light-emitting diodes (OLEDs). The orange-red TADF materials are commonly designed with either large π-conjugated systems or strong intramolecular donor-acceptor (D-A) interactions for red-shift emission and small singlet-triplet energy gap (ΔEST). There are rare reports on the simultaneous incorporation of these two strategies on the same material systems. Herein, two orange-red emitters named 1P2D-BP and 2P2D-DQ have been designed by extending the conjugation degree of the center acceptor DQ and increasing the number distribution of the peripheral donor PXZ units, respectively. The emission peak of 1P2D-BP is red-shifted to 615 nm compared to 580 nm for 2P2D-DQ, revealing the pronounced effect of the conjugation extension on the emission band gap. In addition, the distorted molecular structure yields a small ΔEST of 0.02 eV, favoring the acquisition of a high exciton utilization through an efficient reverse intersystem crossing process. As a result, orange-red OLEDs with both 1P2D-BP and 2P2D-DQ have achieved an external quantum efficiency (EQE) of more than 17%. In addition, the efficient white OLED based on 1P2D-BP is realized through precise exciton assignment and energy transport modulation, showing an EQE of 23.6% and a color rendering index of 82. The present work provides an important reference for the design of high-efficiency narrow-band gap materials in the field of solid-state lighting.

15.
Insects ; 14(7)2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37504614

RESUMEN

The chitin synthase B gene is a key enzyme in the chitin synthesis of insect peritrophic matrix (PM), which affects insects' feeding behavior. The chitin synthase B gene was cloned from the transcription library of Heortia vitessoides Moore. RT-qPCR showed that HvChsb was highly expressed in the larval stage of H. vitessoides, especially on the first day of the pre-pupal stage, as well as in the midgut of larvae and the abdomen of adults. After starvation treatment, HvChsb was found to be significantly inhibited over time. After 48 h of starvation, the feeding experiment showed that HvChsb increased with the prolongation of the re-feeding time. The experimental data showed that feeding affected the expression of HvChsb. HvChsb was effectively silenced via RNA interference; thus, its function was lost, significantly decreasing the survival rate of H. vitessoides. The survival rate from larval-to-pupal stages was only 43.33%, and this rate was accompanied by abnormal phenotypes. It can be seen that HvChsb plays a key role in the average growth and development of H. vitessoides.

16.
ACS Appl Mater Interfaces ; 15(33): 39669-39676, 2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37579002

RESUMEN

Thermally activated delayed fluorescence (TADF) emitters based on multiple resonance (MR) effects are promising for high-definition organic light-emitting diodes (OLEDs) with narrowband emission and high efficiency. However, they still face the challenges of aggregation-caused quenching (ACQ) and spectral broadening. Solution-processable MR-TADF emitters with an external quantum efficiency (EQE) of >20% and a full width at half-maximum (fwhm) of <30 nm have rarely been reported. To construct ACQ-resistant emitters without sacrificing color purity, the aggregation-induced MR-TADF material 6TBN with a rigid B,N-containing polycyclic aromatic hydrocarbon core and four carbazole substituents as well as 12 tert-butyl groups on the periphery is designed. The multidimensional shielded effect largely limits the ACQ, intermolecular interactions, and spectral broadening. Consequently, solution-processed OLEDs based on 6TBN exhibit a maximum EQE of 23.0% and high color purity with a fwhm of 25 nm. Furthermore, the nondoped device achieves a high efficiency (12.3%) and merely a slight widening of the fwhm to 27 nm. This work provides a feasible strategy to achieve MR-TADF materials with resistance to concentration quenching and high color purity.

17.
Chin Med J (Engl) ; 136(23): 2847-2856, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36959686

RESUMEN

BACKGROUND: Type 2 diabetes mellitus (T2DM) is an independent risk factor for colorectal cancer (CRC), and the patients with CRC and T2DM have worse survival. The human gut microbiota (GM) is linked to the development of CRC and T2DM, respectively. However, the GM characteristics in patients with CRC and T2DM remain unclear. METHODS: We performed fecal metagenomic and targeted metabolomics studies on 36 samples from CRC patients with T2DM (DCRC group, n = 12), CRC patients without diabetes (CRC group, n = 12), and healthy controls (Health group, n = 12). We analyzed the fecal microbiomes, characterized the composition and function based on the metagenomics of DCRC patients, and detected the short-chain fatty acids (SCFAs) and bile acids (BAs) levels in all fecal samples. Finally, we performed a correlation analysis of the differential bacteria and metabolites between different groups. RESULTS: Compared with the CRC group, LefSe analysis showed that there is a specific GM community in DCRC group, including an increased abundance of Eggerthella , Hungatella , Peptostreptococcus , and Parvimonas , and decreased Butyricicoccus , Lactobacillus , and Paraprevotella . The metabolomics analysis results revealed that the butyric acid level was lower but the deoxycholic acid and 12-keto-lithocholic acid levels were higher in the DCRC group than other groups ( P < 0.05). The correlation analysis showed that the dominant bacterial abundance in the DCRC group ( Parvimonas , Desulfurispora , Sebaldella , and Veillonellales , among others) was negatively correlated with butyric acid, hyodeoxycholic acid, ursodeoxycholic acid, glycochenodeoxycholic acid, chenodeoxycholic acid, cholic acid and glycocholate. However, the abundance of mostly inferior bacteria was positively correlated with these metabolic acid levels, including Faecalibacterium , Thermococci , and Cellulophaga . CONCLUSIONS: Unique fecal microbiome signatures exist in CRC patients with T2DM compared to those with non-diabetic CRC. Alterations in GM composition and SCFAs and secondary BAs levels may promote CRC development.


Asunto(s)
Neoplasias Colorrectales , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Microbiota , Humanos , Microbioma Gastrointestinal/genética , Bacterias/genética , Ácidos Grasos Volátiles , Neoplasias Colorrectales/metabolismo , Butiratos , Heces/microbiología
18.
Poult Sci ; 102(10): 102974, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37573845

RESUMEN

Pigeon paramyxovirus-1 (PPMV-1), a genetic variant of avian paramyxovirus-1 (APMV-1), has been identified in Columbiformes and is the primary cause of diseases in captive and free-ranging pigeons. However, it has also been reported that PPMV-1 can infect chickens naturally and experimentally, thus posing a potential threat to the poultry industry. This study investigated a lethal outbreak of paramyxovirus infection that occurred among 16 oriental turtle doves (Streptopelia orientalis) in a walk-in aviary at a zoo from March to April 2021. Necropsies were performed, and histopathological findings revealed mild to moderate lymphoplasmacytic infiltration in several organs, such as the pancreas, liver, kidneys, and lungs. Reverse transcription polymerase chain reaction (RT-PCR) using formalin-fixed paraffin-embedded tissue blocks, virus isolation from fresh tissue, and in situ hybridization against the fusion (F) protein confirmed the diagnosis for PPMV-1 infection. The isolated strain NTU/C239/21 was fully sequenced by next-generation sequencing, and the results of phylogenetic analyses revealed that the F protein of NTU/C239/21 shared 98.8% nucleotide sequence identity with Pigeon/Taiwan/AHRI121/2017, which was isolated from a feral pigeon in Taiwan. The present study is the first to identify PPMV-1 infection in Streptopelia orientalis and suggests that Streptopelia orientalis may also play an important role in spreading the infection, similar to pigeons in APMV-1 spreading.


Asunto(s)
Columbidae , Enfermedad de Newcastle , Animales , Columbidae/genética , Enfermedad de Newcastle/epidemiología , Filogenia , Pollos/genética , Virus de la Enfermedad de Newcastle , Secuenciación de Nucleótidos de Alto Rendimiento/veterinaria , Genotipo , Hibridación in Situ/veterinaria
19.
J Nanosci Nanotechnol ; 12(2): 1620-3, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22630014

RESUMEN

Heteroepitaxial growth of metal-catalyst-free indium nitride (InN) nanorods on GaN/sapphire substrates by radio-frequency metal-organic molecular beam epitaxy (RF-MOMBE) system was investigated. We found that different N/In flow ratios together with the growth temperatures greatly influenced the surface morphology of InN nanorods and their structural properties. The InN nanorods have been characterized in detail using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM). Optical property was evaluated by photoluminescence (PL) measurements. At lower growth temperatures, InN nanorods were successfully grown. A pronounced two-dimensional growth mode was observed at higher growth temperature of 500 degrees C, and these films showed preferred orientation along the c-axis. XRD patterns and SEM images reveal that InN nanorods has high quality wurtzite structure with FWHM approaching 900 arcsec, and they have uniform diameters of about 150 nm and length of about 800 nm. Meanwhile, no metallic droplet was observed at the end of the nanostructured InN, and this is strong evidence that the nanorods are grown via the self-catalyst process. The PL peak at 0.8 eV is attributed to the quantum confinement and Moss-Burstein effects. These observations provide some valuable insights into the physical-chemical process for manufacturing InN nanorods devices.

20.
Front Comput Neurosci ; 16: 1052140, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36518995

RESUMEN

At present, gold and bitcoin have become mainstream assets in market transactions. Due to the volatility of gold and bitcoin prices, we can buy and sell assets like gold and bitcoin the same way we buy and sell stocks. The research goal of this article is to develop an optimal trading strategy that maximizes our post-trade returns. By studying the relationship between the two, on the one hand, it supplements and enriches the theoretical research on the rate of return of gold and Bitcoin, on the other hand, it provides a certain reference for investors to construct investment strategies. The research on the cointegration relationship between them has important practical significance. At the same time, it has important practical significance for the research on the cointegration relationship between bitcoin and gold.

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