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1.
Chem Sci ; 15(29): 11515-11520, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39055021

RESUMO

Organocatalytic annulations between allenes and bisnucleophiles represent one of the most convenient routes to various carbocycles and heterocycles. However, most examples are limited to the formation of five- and six-membered rings, probably owing to relatively easy handling of short-chained biselectrophiles. Here we report long-chained α-allyl allenoate-derived 1,6-biselectrophiles for the first time, enabling a phosphine catalyzed [6 + 1] annulation with readily available 1,1-bisnucleophilic reagents. The reaction proceeds via a tandem γ-umpolung addition and δ'-addition process, smoothly constructing both seven-membered N-heterocycles and carbocycles with a broad scope of substrates, high atom economy and excellent enantioselectivity (up to 99% yield and up to 96% ee). Mechanistic experiments revealed a conversion of the 1,6-dipole into a 1,6-biselectrophilic intermediate through proton abstraction.

2.
Ecotoxicol Environ Saf ; 282: 116692, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38971097

RESUMO

Viola yedoensis Makino (Vy) is a well-known traditional Chinese medicine widely used to treat inflammatory diseases. However, the regulatory effects of dietary Vy supplementation on lipopolysaccharide (LPS)-induced intestinal damage in broilers and the underlying molecular mechanisms remain unclear. In this study, broilers were intraperitoneally injected with 1 mg/kg LPS on days 17, 19 and 21 to induce intestinal damage. Vy supplementation at 0.5, 1.5 and 4.5 % in the diet was administered separately for 21 days to investigate the potential protective effects of Vy supplementation against LPS-induced intestinal impairment in broilers. Vy supplementation improved intestinal morphology and restored growth performance. Vy supplementation attenuated intestinal inflammation by regulating the nuclear factor kappa B (NF-κB) / NLR family pyrin domain-containing 3 (NLRP3) signaling pathway and inhibited its downstream pro-inflammatory factor levels. In addition, Vy supplementation relieved intestinal oxidative impairment by regulating the nuclear factor erythroid-2 related factor 2 (Nrf2) / mitogen-activated protein kinase (MAPK) signaling pathway and downstream antioxidant enzyme activity. Vy supplementation reduced LPS-induced mitochondrial damage and apoptosis. Furthermore, Vy supplementation alleviated LPS-induced intestinal inflammation and oxidative damage in chickens by increasing the abundance of protective bacteria (Lactobacillus and Romboutsia) and reducing the number of pathogenic bacteria (unclassified_f_Ruminococcaceae, unclassified_f_Oscillospiraceae and norank_f_norank_o_Clostridia_vadinBB60_group). Overall, Vy supplementation effectively ameliorated LPS-induced intestinal damage by regulating the NF-κB-NLRP3/Nrf2-MAPK signaling pathway and maintaining intestinal microbiota balance. Vy supplementation can be used as a dietary supplement to protect broilers against intestinal inflammation and oxidative damage.

3.
Genes (Basel) ; 15(7)2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-39062672

RESUMO

In the present study, the mitochondrial genomic characteristics of Acanthopsetta nadeshnyi have been reported and have depicted the phylogenetic relationship among Pleuronectidae. Combined with a comparative analysis of 13 PCGs, the TN93 model was used to review the neutral evolution and habitat evolution catalysis of the mitogenome to verify the distancing and purification selectivity of the mitogenome in Pleuronectidae. At the same time, a species differentiation and classification model based on mitogenome analysis data was established. This study is expected to provide a new perspective on the phylogenetic relationship and taxonomic status of A. nadeshnyi and lay a foundation for further exploration of environmental and biological evolutionary mechanisms.


Assuntos
Evolução Molecular , Genoma Mitocondrial , Filogenia , Animais , Linguados/genética , Linguados/classificação
4.
J Community Health Nurs ; : 1-9, 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38909288

RESUMO

We aimed to analyze the effects of exclusive breastfeeding duration on the occurrence and course of pneumonia in infants aged up to 6 months. Prospective case-control study. This study was conducted from August 2020 to August 2022 at a maternity and child health hospital in China. A total of 218 infants up to 6 months of age with pneumonia were included in the analyses. Health data were obtained using a hospitalization information system or an interview-based questionnaire. Univariate and multivariate logistic regression analyses were performed to analyze the data. The incidence of pneumonia, hospitalization duration, and costs to participants were significantly affected by the duration of exclusive breastfeeding (p < 0.01). The incidence of pneumonia among participants with different exclusive breastfeeding durations also differed significantly (p < 0.01). The shorter the duration of exclusive breastfeeding, the higher the incidence of pneumonia among infants. We found that the longer the exclusive breastfeeding duration in infants up to 6 months of age, the lower the recurrence of pneumonia, the shorter the hospital stay, and the lower the hospital costs. The rate of exclusive breastfeeding for infants up to 6 months of age should be increased as much as possible to reduce the occurrence of pneumonia and hospital costs.

5.
Phytomedicine ; 130: 155739, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-38797027

RESUMO

BACKGROUND: Atractylodes macrocephala Koidz. (Baizhu in Chinese, BZ) is a typical traditional edible-medicinal herb used for thousands of years. Known as "the spleen-reinforcing medicine", it is often used clinically to treat reduced digestive function, abdominal distension, and diarrhoea, which are all caused by spleen deficiency. Among BZ's processing products, honey bran-fried BZ (HBBZ) is the only processed product recorded in BZ in the 2020 Chinese Pharmacopoeia (ChP). There are differences in effectiveness, traditional application, and clinical indications between them. PURPOSE: This review reviewed BZ and its main product HBBZ from botany, ethnopharmacology, chemical composition, pharmacological effectiveness, and safety. The changes in chemical composition and pharmacological effectiveness of BZ induced by the processing of traditional Chinese medicine were emphatically described. METHODS: Keywords related to Atractylodes macrocephala Koidz., honey bran frying, essential oil, lactones, polysaccharide and combinations to include published studies of BZ and HBBZ from 2004-2023 were searched in the following databases: Pubmed, Chengdu University of TCM Library, Google Scholar, China National Knowledge Infrastructure (CNKI), and Wanfang database. All studies, published in English or Chinese, were included. However, in the process of chemical composition collection, we reviewed all available literature on the chemical composition of BZ and HBBZ. CONCLUSION: Honey bran frying processing methods will affect BZ's chemical composition and pharmacological effectiveness. The types and contents of chemical components in the HBBZ showed some changes compared with those in BZ. For example, the content of volatile oil decreased and the content of lactones increased after stir-fried bran. In addition, new ingredients such as phenylacetaldehyde, 2-acetyl pyrrole, 6- (1,1-dimethylethyl) -3,4-dihydro-1 (2H) -naphthalone and 5-hydroxymethylfurfural appeared. Both BZ and HBBZ have a variety of pharmacological effectiveness. After stir-fried with honey bran, the "Zao Xing" is reduced, and the efficacy of tonify spleen is strengthened, which is more suitable for patients with weak spleen and stomach.


Assuntos
Atractylodes , Medicamentos de Ervas Chinesas , Mel , Medicina Tradicional Chinesa , Atractylodes/química , Mel/análise , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/química , Humanos , Lactonas/farmacologia , Lactonas/análise , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Animais
6.
Org Lett ; 26(19): 4037-4042, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38717087

RESUMO

A novel phosphine-catalyzed domino annulation reaction of γ-vinyl allenoates and o-aminotrifluoacetophenones for the construction of terahydrofuro[3,2-c]quinoline derivatives has been developed. In this domino reaction, two kinds of terahydrofuro[3,2-c]quinoline compounds containing CF3 groups were obtained with good yields under mild conditions, three new C-N, C-C, and C-O bonds can be built in one step, and the reaction selectivity is achieved by adjusting the reaction conditions. Furthermore, preliminary studies on an asymmetric variant of this reaction proceeded with moderate enantioselectivity.

7.
World J Gastrointest Surg ; 16(4): 1208-1214, 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38690049

RESUMO

BACKGROUND: Lymphangiomas in the gastrointestinal tract are extremely rare in adults. As a benign lesion, small intestine lymphangiomas often remain asymptomatic and pose challenges for definitive diagnosis. However, lymphangiomas can give rise to complications such as abdominal pain, bleeding, volvulus, and intussusception. Here, we report a case of jejunal cavernous lymphangioma that presented with intermittent melena and refractory anemia in a male adult. CASE SUMMARY: A 66-year-old man presented with intermittent melena, fatigue and refractory anemia nine months prior. Esophagogastroduodenoscopy and colonoscopy were performed many times and revealed no apparent bleeding. Conservative management, including transfusion, hemostasis, gastric acid secretion inhibition and symptomatic treatment, was performed, but the lesions tended to recur shortly after surgery. Ultimately, the patient underwent capsule endoscopy, which revealed a more than 10 cm lesion accompanied by active bleeding. After single-balloon enteroscopy and biopsy, a diagnosis of jejunal cavernous lymphangioma was confirmed, and the patient underwent surgical resection. No complications or recurrences were observed postoperatively. CONCLUSION: Jejunal cavernous lymphangioma should be considered a cause of obscure gastrointestinal bleeding. Capsule endoscopy and single-balloon enteroscopy can facilitate diagnosis. Surgical resection is an effective management method.

8.
Zool Res ; 45(3): 520-534, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38682434

RESUMO

Iridovirus poses a substantial threat to global aquaculture due to its high mortality rate; however, the molecular mechanisms underpinning its pathogenesis are not well elucidated. Here, a multi-omics approach was applied to groupers infected with Singapore grouper iridovirus (SGIV), focusing on the roles of key metabolites. Results showed that SGIV induced obvious histopathological damage and changes in metabolic enzymes within the liver. Furthermore, SGIV significantly reduced the contents of lipid droplets, triglycerides, cholesterol, and lipoproteins. Metabolomic analysis indicated that the altered metabolites were enriched in 19 pathways, with a notable down-regulation of lipid metabolites such as glycerophosphates and alpha-linolenic acid (ALA), consistent with disturbed lipid homeostasis in the liver. Integration of transcriptomic and metabolomic data revealed that the top enriched pathways were related to cell growth and death and nucleotide, carbohydrate, amino acid, and lipid metabolism, supporting the conclusion that SGIV infection induced liver metabolic reprogramming. Further integrative transcriptomic and proteomic analysis indicated that SGIV infection activated crucial molecular events in a phagosome-immune depression-metabolism dysregulation-necrosis signaling cascade. Of note, integrative multi-omics analysis demonstrated the consumption of ALA and linoleic acid (LA) metabolites, and the accumulation of L-glutamic acid (GA), accompanied by alterations in immune, inflammation, and cell death-related genes. Further experimental data showed that ALA, but not GA, suppressed SGIV replication by activating antioxidant and anti-inflammatory responses in the host. Collectively, these findings provide a comprehensive resource for understanding host response dynamics during fish iridovirus infection and highlight the antiviral potential of ALA in the prevention and treatment of iridoviral diseases.


Assuntos
Doenças dos Peixes , Iridovirus , Fígado , Ácido alfa-Linolênico , Animais , Ácido alfa-Linolênico/metabolismo , Doenças dos Peixes/virologia , Doenças dos Peixes/metabolismo , Fígado/metabolismo , Fígado/virologia , Iridovirus/fisiologia , Infecções por Vírus de DNA/veterinária , Infecções por Vírus de DNA/virologia , Metabolômica , Antivirais/farmacologia , Transcriptoma , Reprogramação Metabólica , Multiômica
9.
J Appl Microbiol ; 135(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38509027

RESUMO

AIMS: In this work, we aimed to isolate marine bacteria that produce metabolites with antifungal properties. METHODS AND RESULTS: Paenibacillus polymyxa 188 was isolated from a marine sediment sample, and it showed excellent antifungal activity against many fungi pathogenic to plants (Fusarium tricinctum, Pestalotiopsis clavispora, Fusarium oxysporum, F. oxysporum f. sp. Cubense (Foc), Curvularia plantarum, and Talaromyces pinophilus) and to humans (Aspergillus terreus, Penicillium oxalicum, and Microsphaeropsis arundinis). The antifungal compounds produced by P. polymyxa 188 were extracted and analyzed using matrix-assisted laser desorption ionization time-of-flight mass spectrometry. The complete genome sequence and biosynthetic gene clusters of P. polymyxa 188 were characterized and compared with those of other strains. A total of 238 carbohydrate-active enzymes (CAZymes) were identified in P. polymyxa 188. Two antibiotic gene clusters, fusaricidin and tridecaptin, exist in P. polymyxa 188, which is different from other strains that typically have multiple antibiotic gene clusters. CONCLUSIONS: Paenibacilluspolymyxa 188 was identified with numerous biosynthetic gene clusters, and its antifungal ability against pathogenic fungi was verified.


Assuntos
Paenibacillus polymyxa , Paenibacillus , Humanos , Paenibacillus polymyxa/metabolismo , Antifúngicos/química , Antibacterianos/metabolismo , Paenibacillus/genética
10.
J Geriatr Cardiol ; 21(2): 219-231, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38544498

RESUMO

BACKGROUND: Myocardial infarction (MI) is a critical cardiovascular event with multifaceted etiology, involving several genetic and environmental factors. It is essential to understand the function of plasma metabolites in the development of MI and unravel its complex pathogenesis. METHODS: This study employed a bidirectional Mendelian randomization (MR) approach to investigate the causal relationships between plasma metabolites and MI risk. We used genetic instruments as proxies for plasma metabolites and MI and conducted MR analyses in both directions to assess the impact of metabolites on MI risk and vice versa. In addition, the large-scale genome-wide association studies datasets was used to identify genetic variants associated with plasma metabolite (1400 metabolites) and MI (20,917 individuals with MI and 440,906 individuals without MI) susceptibility. Inverse variance weighted was the primary method for estimating causal effects. MR estimates are expressed as beta coefficients or odds ratio (OR) with 95% CI. RESULTS: We identified 14 plasma metabolites associated with the occurrence of MI (P < 0.05), among which 8 plasma metabolites [propionylglycine levels (OR = 0.922, 95% CI: 0.881-0.965, P < 0.001), gamma-glutamylglycine levels (OR = 0.903, 95% CI: 0.861-0.948, P < 0.001), hexadecanedioate (C16-DC) levels (OR = 0.941, 95% CI: 0.911-0.973, P < 0.001), pentose acid levels (OR = 0.923, 95% CI: 0.877-0.972, P = 0.002), X-24546 levels (OR = 0.936, 95% CI: 0.902-0.971, P < 0.001), glycine levels (OR = 0.936, 95% CI: 0.909-0.964, P < 0.001), glycine to serine ratio (OR = 0.930, 95% CI: 0.888-0.974, P = 0.002), and mannose to trans-4-hydroxyproline ratio (OR = 0.912, 95% CI: 0.869-0.958, P < 0.001)] were correlated with a decreased risk of MI, whereas the remaining 6 plasma metabolites [1-palmitoyl-2-arachidonoyl-GPE (16:0/20:4) levels (OR = 1.051, 95% CI: 1.018-1.084, P = 0.002), behenoyl dihydrosphingomyelin (d18:0/22:0) levels (OR = 1.076, 95% CI: 1.027-1.128, P = 0.002), 1-stearoyl-2-docosahexaenoyl-GPE (18:0/22:6) levels (OR = 1.067, 95% CI: 1.027-1.109, P = 0.001), alpha-ketobutyrate levels (OR = 1.108, 95% CI: 1.041-1.180, P = 0.001), 5-acetylamino-6-formylamino-3-methyluracil levels (OR = 1.047, 95% CI: 1.019-1.076, P < 0.001), and N-acetylputrescine to (N (1) + N (8))-acetylspermidine ratio (OR = 1.045, 95% CI: 1.018-1.073, P < 0.001)] were associated with an increased risk of MI. Furthermore, we also observed that the mentioned relationships were unaffected by horizontal pleiotropy (P > 0.05). On the contrary, MI did not lead to significant alterations in the levels of the aforementioned 14 plasma metabolites (P > 0.05 for each comparison). CONCLUSIONS: Our bidirectional MR study identified 14 plasma metabolites associated with the occurrence of MI, among which 13 plasma metabolites have not been reported previously. These findings provide valuable insights for the early diagnosis of MI and potential therapeutic targets.

11.
Inorg Chem ; 63(13): 5945-5951, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38502918

RESUMO

Alkali-metal rare-earth carbonates (ARECs) find great potential in nonlinear optical applications. As the most common method, the hydrothermal reaction is widely used in synthesizing ARECs. The black-box nature of the hydrothermal reaction makes it difficult for understanding the formation processes and therefore may slow down the pace of structural discovery. Here, by simply soaking the rare-earth carbonates in Na2CO3 solutions, we successfully obtain a series of noncentrosymmetric Na3RE(CO3)3·6H2O (RE = Tb 1, Sm 2, Eu 3, Gd 4, Dy 5, Ho 6, and Er 7) compounds without using the high-temperature hydrothermal method. The transformation process, investigated by powder X-ray diffraction and scanning electron microscopy, is governed by the concentration of the soaking solutions. Na3Tb(CO3)3·6H2O, as an example, is studied structurally, and its physical properties are characterized. It exhibits a second harmonic generation effect of 0.5 × KDP and a short UV cutoff edge of 222 nm (5.8 eV). Our study provides insights for exploring new AREC structures, which may further advance the development of carbonate nonlinear optical crystals.

12.
Inorg Chem ; 63(10): 4697-4706, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38407040

RESUMO

Benefiting from the unique photoluminescence behavior of the lanthanide(III) ions and organic ligands, a lanthanide(III) metal-organic framework (Ln-MOF) material can simultaneously demonstrate photoluminescence of lanthanide(III) cations and organic molecules and endow its superior applications of fluorescence sensing behaviors. Herein, we present a europium(III) MOF material {[Eu2(BPTA)·(CH3COO)2·3DMA]·0.5DMA·3H2O}n (1) (where H4BPTA is 3,3',5,5'-biphenyltetracarboxylic acid) for photoluminescence performance of quantitatively sensing the inflammatory marker neopterin (Neo). The obtained 1 comprises Eu2(COO)4 paddlewheel secondary building units, which could be bridged by BPTA4- ligands to extend a 2D framework. The fluorescence titration indicates 1 can achieve simultaneous fluorescence behavior of Eu3+ ions and Neo via on-off ratiometric effects and thus could be exploited as the ratiometric fluorescence sensor matrix. Such a fluorescence phenomenon of 1 as a ratiometric sensor for quantitative detection of Neo via an on-off ratiometric effect is never observed in MOF chemistry. Moreover, naked-eye visible color variations of the fluorescence for 1 could be observed from red to blue with increasing concentrations of Neo, confirmed by fluorescent test strips as well as portable fluorescent hydrogels. And 1 also shows a low detection limit of 15.11 nM. A synergetic contribution of the competitive absorption, fluorescence resonance energy-transfer, and photoinduced electron-transfer mechanisms between Neo and the framework of 1 realizes the on-off ratiometric fluorescence behavior for Neo detection, supported by the UV-vis spectral overlap experiment and DFT calculations.

13.
Toxicon ; 241: 107652, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38395262

RESUMO

T-2 toxin, a type-A trichothecene mycotoxin, exists ubiquitously in mildewed foods and feeds. Betulinic acid (BA), a pentacyclic triterpenoid derived from plants, has the effect of relieving inflammation and oxidative stress. The purpose of this study was to investigate whether BA mitigates lung impairment caused by T-2 toxin and elucidate the underlying mechanism. The results indicated that T-2 toxin triggered the inflammatory cell infiltration, morphological alterations and cell apoptosis in the lungs. It is gratifying that BA ameliorated T-2 toxin-caused lung injury. The protein expression of nuclear factor erythrocyte 2-related factor 2 (Nrf2) pathway and the markers of antioxidative capability were improved in T-2 toxin induced lung injury by BA mediated protection. Simultaneously, BA supplementation could suppress T-2 toxin-induced mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-κB)-dependent inflammatory response and mitochondrial apoptotic pathway. Therefore, T-2 toxin gave rise to pulmonary toxicity, but these changes were moderated by BA administration through regulation of the Nrf2/MAPK/NF-κB pathway, which maybe offer a viable alternative for mitigating the lung impairments caused by the mycotoxin.


Assuntos
Lesão Pulmonar , Toxina T-2 , Humanos , NF-kappa B/metabolismo , Toxina T-2/toxicidade , Toxina T-2/metabolismo , Ácido Betulínico , Fator 2 Relacionado a NF-E2/metabolismo , Lesão Pulmonar/induzido quimicamente , Lesão Pulmonar/tratamento farmacológico , Triterpenos Pentacíclicos , Transdução de Sinais , Estresse Oxidativo , Proteínas Quinases Ativadas por Mitógeno/metabolismo
14.
Adv Sci (Weinh) ; 11(14): e2308028, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38308108

RESUMO

Design of flexible porous materials where the diffusion of guest molecules is regulated by the dynamics of contracted pore aperture is challenging. Here, a flexible porous self-assembly consisting of 1D channels with dynamic bottleneck gates is reported. The dynamic pendant naphthimidazolylmethyl moieties at the channel necks provide kinetic gate function, that enables unusual adsorption for light hydrocarbons. The adsorption for CO2 is mainly dominated by thermodynamics with the uptakes decreasing with increasing temperature, whereas the adsorptions for larger hydrocarbons are controlled by both thermodynamics and kinetics resulting in an uptake maximum at a temperature threshold. Such an unusual adsorption enables temperature-dependent separation of CO2 from the corresponding hydrocarbons.

15.
Chem Commun (Camb) ; 60(15): 2066-2069, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38289382

RESUMO

The first (5+1) annulation of allenoates and pyrazolones catalyzed by CH3OK has been reported. A series of spiro-pyrazolone derivatives were obtained as single diastereomers in high yields (≤95%) under mild conditions. The synthetic utility was demonstrated by a scale-up reaction and various transformations of the products. The proposed mechanism suggests that the allenoate works as a 1,5-biselectrophilic 5C synthon for the first time and controlled experiments disclose that K+ plays an important role in the diastereoselectivity-determining step through an eight-membered ring transition state. Also, this 1,5-biselectrophilic allenoate will be able to act as a 5C synthon for (5+n) annulation.

16.
Nanoscale ; 15(45): 18233-18240, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37943087

RESUMO

Achieving self-powered photodetection without biasing is a notable challenge for photodetectors. In this work, we demonstrate the successful fabrication of large-scale van der Waals epitaxial molybdenum disulfide (MoS2) on a p-GaN/sapphire substrate using a straightforward chemical vapor deposition (CVD) technique. Our research primarily centers on the characterization of these photodetectors produced through this method. The MoS2/GaN heterojunction photodetector showcases a broad and extensive photoresponse spanning from ultraviolet A (UVA) to near-infrared (NIR). When illuminated by a 532 nm laser, its self-powered photoresponse is characterized by a rise time (τr) of ∼18.5 ms and a decay time (τd) of ∼123.2 ms. The photodetector achieves a responsivity (R) of ∼0.13 A W-1 and a specific detectivity (D*) of ∼3.8 × 1010 Jones at zero bias. Additionally, while utilizing a 404 nm laser, the photodetector reaches a maximum R and D* of ∼1.7 × 104 A/W and ∼1.6 × 1013 Jones, respectively, at Vb = 5 V. The operational mechanism of the device can be explained by the diode characteristics involving a tunneling current in the presence of reverse bias. The exceptional performance of these photodetectors can be attributed to the pristine interface between the CVD-grown MoS2 and GaN, providing an impeccably clean tunneling surface. Additionally, our investigation has unveiled that MoS2/GaN heterostructure photodetectors, featuring MoS2 coverage percentages spanning from 20% to 50%, exhibit improved responsivity capabilities at an external bias voltage. As a result, this facile CVD growth technique for MoS2 photodetectors holds significant potential for large-scale production in the manufacturing industry.

17.
Cancer Commun (Lond) ; 43(12): 1312-1325, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37837629

RESUMO

BACKGROUND: Circulating tumor DNA (ctDNA) is a promising biomarker for predicting relapse in multiple solid cancers. However, the predictive value of ctDNA for disease recurrence remains indefinite in locoregional gastric cancer (GC). Here, we aimed to evaluate the predictive value of ctDNA in this context. METHODS: From 2016 to 2019, 100 patients with stage II/III resectable GC were recruited in this prospective cohort study (NCT02887612). Primary tumors were collected during surgical resection, and plasma samples were collected perioperatively and within 3 months after adjuvant chemotherapy (ACT). Somatic variants were captured via a targeted sequencing panel of 425 cancer-related genes. The plasma was defined as ctDNA-positive only if one or more variants detected in the plasma were presented in at least 2% of the primary tumors. RESULTS: Compared with ctDNA-negative patients, patients with positive postoperative ctDNA had moderately higher risk of recurrence [hazard ratio (HR) = 2.74, 95% confidence interval (CI) = 1.37-5.48; P = 0.003], while patients with positive post-ACT ctDNA showed remarkably higher risk (HR = 14.99, 95% CI = 3.08-72.96; P < 0.001). Multivariate analyses indicated that both postoperative and post-ACT ctDNA positivity were independent predictors of recurrence-free survival (RFS). Moreover, post-ACT ctDNA achieved better predictive performance (sensitivity, 77.8%; specificity, 90.6%) than both postoperative ctDNA and serial cancer antigen. A comprehensive model incorporating ctDNA for recurrence risk prediction showed a higher C-index (0.78; 95% CI = 0.71-0.84) than the model without ctDNA (0.71; 95% CI = 0.64-0.79; P = 0.009). CONCLUSIONS: Residual ctDNA after ACT effectively predicts high recurrence risk in stage II/III GC, and the combination of tissue-based and circulating tumor features could achieve better risk prediction.


Assuntos
DNA Tumoral Circulante , Neoplasias Gástricas , Humanos , Quimioterapia Adjuvante , DNA Tumoral Circulante/genética , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Estudos Prospectivos , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/genética , Neoplasias Gástricas/cirurgia , Estudos de Coortes
18.
Chem Commun (Camb) ; 59(88): 13215-13218, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37853789

RESUMO

An unprecedented phosphine-catalyzed formal Buchner [6+1] annulation of a newly designed allenoate has been developed, providing a series of cycloheptatriene derivatives in moderate to good yields (up to 99%). This reaction demonstrates that the introduction of an electrophilic allylic group to allenoates effectively extends the reaction scope of phosphine-catalyzed annulation, providing a concise route to cycloheptatrienes. Mechanistic study indicated that this reaction involves a [4+2] Diels-Alder reaction and ring expansion of the bicyclo[4.1.0] moiety, which is similar to the Buchner reaction. Notably, an enantioselective variant of this [6+1] annulation can also be performed using a chiral iminophosphine catalyst.

19.
Polymers (Basel) ; 15(20)2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37896279

RESUMO

Triboelectric nanogenerators (TENGs) are a kind of mechanical energy harvester with a larger force sensing range and good energy conversion, which is often applied to human kinetic energy collection and motion sensing devices. Polymer materials are the most commonly used materials in TENGs' triboelectric layers due to their high plasticity and good performance. Regarding the application of TENGs in insoles, research has often used brittle Teflon for high output performance together with hard materials, such as springs, for the mechanism to maintain its stability. However, these combined materials increase the weight and hardness of the insoles. Here, we propose a polyethylene terephthalate (PET)-based TENG with a micro-needle polydimethylsiloxane (PDMS) elastomer, referred to as MN-PDMS-TENG, to enhance performance and maintain comfort flexibility, and structural stability. Compared with a flat PDMS, the TENG with a microstructure enhances the output open-circuit voltage (Voc) from 54.6 V to 129.2 V, short-circuit current (Isc) from 26.16 µA to 64.00 µA, power from 684 µW to 4.1 mW, and ability to light up from 70 to 120 LEDs. A special three-layer TENG insole mechanism fabricated with the MN-PDMS-TENG and elastic materials gives the TENG insole high stability and the ability to maintain sufficient flexibility to fit in a shoe. The three-layer TENG insole transforms human stepping force into electric energy of 87.2 V, which is used as a self-powered force sensor. Moreover, with the calibration curve between voltage and force, it has a sensitivity of 0.07734 V/N with a coefficient of determination of R2 = 0.91 and the function between force and output voltage is derived as F = 12.93 V - 92.10 under human stepping force (300~550 N). Combined with a micro-control unit (MCU), the three-layer TENG insole distinguishes the user's motion force at different parts of the foot and triggers a corresponding device, which can potentially be applied in sports and on rehabilitation fields to record information or prevent injury.

20.
Angew Chem Int Ed Engl ; 62(41): e202310133, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37610557

RESUMO

Aryl amines are of constant interest in organic synthesis owing to their ubiquity in natural products, pharmaceuticals, and organic materials. However, C-H amination or pre-functionalization frequently results in uncontrollable site selectivity, over activation and the generation of inseparable mixtures of regio-isomers. Here we present a novel metal free Dötz-type aminobenzannulation reaction that circumvents the selectivity issues inherent in aromatic chemistry, as well as the use of stoichiometric unstable organolithium reagents and toxic chromium complexes. The concept of utilizing readily available isocyanides and Morita-Baylis-Hillman (MBH) carbonates to achieve 1,1-dipoles cross-coupling to construct ketenimine is the key to success, which has been experimentally and computationally verified. The tandem 6π-electrocyclization/aromatization process offers a versatile method for synthesizing functionalized anilines, fused aryl amines and fused heteroaryl amines.

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