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1.
Opt Lett ; 49(15): 4326-4329, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090927

RESUMO

We present what we believe is the first report on a polarization-insensitive 3 × 3 silicon star-crossing utilizing a composite subwavelength metamaterial waveguide structure. Two different types of subwavelength grating metamaterials (nanohole grating and fan-shaped bent subwavelength grating) are respectively used to address diffraction issues in the crossing region and mode interference issues caused by a compact non-adiabatic design. This approach results in a device with an ultra-compact footprint of 12.68 × 10.98 µm2 on a standard 220 nm silicon-on-insulator (SOI) platform. Simulation results show low insertion loss (IL) values of <0.2 dB/0.3 dB and suppressed cross talk (CT) levels of <-27.2 dB/-23.6 dB for TE/TM polarizations across a wavelength range of 100 nm (1500-1600 nm). Experimental measurements of the fabricated devices confirm outstanding performance, with IL values of <0.35 dB/0.4 dB and CT levels of <-31.5 dB/-28.6 dB for TE/TM polarization in the C-band.

2.
Healthc Technol Lett ; 11(4): 252-257, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39100501

RESUMO

The goal of this work is to develop a Machine Learning model to predict the need for both invasive and non-invasive mechanical ventilation in intensive care unit (ICU) patients. Using the Philips eICU Research Institute (ERI) database, 2.6 million ICU patient data from 2010 to 2019 were analyzed. This data was randomly split into training (63%), validation (27%), and test (10%) sets. Additionally, an external test set from a single hospital from the ERI database was employed to assess the model's generalizability. Model performance was determined by comparing the model probability predictions with the actual incidence of ventilation use, either invasive or non-invasive. The model demonstrated a prediction performance with an AUC of 0.921 for overall ventilation, 0.937 for invasive, and 0.827 for non-invasive. Factors such as high Glasgow Coma Scores, younger age, lower BMI, and lower PaCO2 were highlighted as indicators of a lower likelihood for the need for ventilation. The model can serve as a retrospective benchmarking tool for hospitals to assess ICU performance concerning mechanical ventilation necessity. It also enables analysis of ventilation strategy trends and risk-adjusted comparisons, with potential for future testing as a clinical decision tool for optimizing ICU ventilation management.

3.
Nat Commun ; 15(1): 7038, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39147846

RESUMO

Soft-matter-based photonic crystals like blue-phase liquid crystals (BPLC) have potential applications in wide-ranging photonic and bio-chemical systems. To date, however, there are limitations in the fabrication of large monocrystalline BPLCs. Traditional crystal-growth process involves the transition from a high-temperature disordered phase to an ordered (blue) phase and is generally slow (takes hours) with limited achievable lattice structures, and efforts to improve molecular alignment through post-crystallization field application typically prove ineffective. Here we report a systematic study on the molecular self-assembly dynamics of BPLC starting from a highly ordered phase in which all molecules are unidirectionally aligned by a strong electric field. We have discovered that, near the high-temperature end of the blue phase, if the applied field strength is then switched to an intermediate level or simply turned off, large-area monocrystalline BPLCs of various symmetries (tetragonal, orthorhombic, cubic) can be formed in minutes. Subsequent temperature tuning of the single crystal at a fixed applied field allows access to different lattice parameters and the formation of never-before-seen monoclinic structures. The formed crystals remain stable upon field removal. The diversity of stable monocrystalline BPLCs with widely tunable crystalline symmetries, band structures, and optical dispersions will significantly improve and expand their application potentials.

4.
BMC Pulm Med ; 24(1): 368, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39080576

RESUMO

BACKGROUND: Hepatic steatosis and its related complications are risk factors for multiple respiratory diseases; however, the causal relationship between metabolic dysfunction-associated steatotic liver disease (MASLD) and pulmonary function remains controversial. We aimed to identify it using a national cohort and Mendelian randomization (MR). METHODS: We enrolled 30,442 participants from the 2007 to 2012 National Health and Nutrition Examination Survey. Demographics, pulmonary function indices (forced expiratory volume in 1 s [FEV1], forced vital capacity [FVC]), and variables used to calculate the liver fat score (LFS) were collected. A two-sample MR analysis employing the summary data of genome-wide association studies on MASLD and FEV1/FVC, chronic obstructive pulmonary disease (COPD), and asthma from the Finngen Biobank and Medical Research Council Integrative Epidemiology Unit was performed. RESULTS: A total of 3,462 participants, 1,335 of whom had MASLD (LFS > -0.640), were finally included in the study. The FEV1 (3,204.7 vs. 3,262.5 ml, P = 0.061), FVC (4,089.1 vs. 4,143.8 ml, P = 0.146), FEV1/FVC ratio (78.5% vs. 78.8%, P = 0.233), and FEV1/predicted FEV1 ratio (146.5% vs. 141.7%, P = 0.366) were not significantly different between people with MASLD and those without. Additionally, the MR analysis suggested no causal correlation between MASLD and FEV1/FVC (P = 0.817), MASLD and COPD (P = 0.407), and MASLD and asthma (P = 0.808). Reverse MR studies showed no causal relationships yet (all P > 0.05). CONCLUSION: Our study provides convincing evidence that there is no causal association between MASLD and pulmonary function.


Assuntos
Asma , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Inquéritos Nutricionais , Doença Pulmonar Obstrutiva Crônica , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Asma/genética , Asma/fisiopatologia , Asma/epidemiologia , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Capacidade Vital , Volume Expiratório Forçado , Idoso , Adulto , Fatores de Risco , Pulmão/fisiopatologia , Fígado Gorduroso/genética , Fígado Gorduroso/fisiopatologia , Testes de Função Respiratória
5.
Zookeys ; 1206: 231-239, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39015532

RESUMO

The Pselaphodes Westwood complex of genera is represented in Hubei Province by four genera and eight species. Recent field work at Wanchaoshan Nature Reserve, Xingshan County revealed a small series of material belonging to this complex. In this paper, we describe Pselaphodeswanchaoshanus sp. nov. and provide new faunistic data for P.nomurai Yin, Li & Zhao. A key to the hitherto known members of Pselaphodes complex that occur in Hubei is provided to facilitate ready species identification.

6.
Animal Model Exp Med ; 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38992966

RESUMO

BACKGROUND: Macrophages are the primary innate immune cells encountered by the invading coronaviruses, and their abilities to initiate inflammatory reactions, to maintain the immunity homeostasis by differential polarization, to train the innate immune system by epigenic modification have been reported in laboratory animal research. METHODS: In the current in vitro research, murine macrophage RAW 264.7 cell were infected by mouse hepatitis virus, a coronavirus existed in mouse. At 3-, 6-, 12-, 24-, and 48-h post infection (hpi.), the attached cells were washed with PBS and harvested in Trizol reagent. Then The harvest is subjected to transcriptome sequencing. RESULTS: The transcriptome analysis showed the immediate (3 hpi.) up regulation of DEGs related to inflammation, like Il1b and Il6. DEGs related to M2 differential polarization, like Irf4 showed up regulation at 24 hpi., the late term after viral infection. In addition, DEGs related to metabolism and histone modification, like Ezh2 were detected, which might correlate with the trained immunity of macrophages. CONCLUSIONS: The current in vitro viral infection study showed the key innated immunity character of macrophages, which suggested the replacement value of viral infection cells model, to reduce the animal usage in preclinical research.

7.
Int J Surg Case Rep ; 120: 109867, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38870658

RESUMO

INTRODUCTION: Solid pseudopapillary neoplasms (SPNs) of the pancreas are rare neoplasms, accounting for only 1 %-2 % of all pancreatic tumors, and predominantly affect female patients. CASE PRESENTATION: The present case report details a patient presenting to the emergency department with abdominal pain for 3 days who ultimately received a diagnosis of SPNs in the pancreatic body and tail. A contrast-enhanced computed tomography (CT) scan revealed a sizable mass arising from the pancreas, featuring an enhancing cystic component with involvement of the liver and spleen. The patient underwent subsequent exploratory laparotomy, a distal pancreatectomy, splenectomy, and partial hepatectomy. SPN diagnosis was confirmed by histopathology and immunohistochemistry with negative resection margins. CLINICAL DISCUSSION: Approximately 70 % of SPN cases are asymptomatic and are incidentally discovered. Despite advances in diagnostic modalities, preoperative diagnosis of SPNs remains a clinical challenge. Surgical management with negative resection margins remains the primary treatment approach. The recurrence rate after surgical resection has been reported to be 3 %-9 %. The prognosis for SPNs limited to the pancreas is generally favorable, with a cure rate exceeding 95 % after complete surgical resection. CONCLUSION: An SPN of the pancreas is a rare tumor observed in young female patients. Although it is classified as a malignant tumor, SPN has low malignant potential. Aggressive surgical resection, however, has proven effective in curing SPN for the majority of patients.

8.
Mar Drugs ; 22(6)2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38921552

RESUMO

Developing novel, safe, and efficient proangiogenic drugs is an important approach for the prevention and treatment of cardiovascular diseases. In this study, 4 new compounds, including 3 azaphilones (1-3) and 1 dihydroisocoumarin (4), as well as 13 known compounds (5-17), were isolated from the sea-mud-derived fungus Neopestalotiopsis sp. HN-1-6 from the Beibu Gulf of China. The structures of the new compounds were determined by NMR, MS, ECD, and NMR calculations. Compounds 3, 5, and 7 exhibited noteworthy proangiogenic activities in a zebrafish model at a concentration of 40 µM, without displaying cytotoxicity toward five human cell lines. In addition, some compounds demonstrated antibacterial effects against Staphylococcus aureus, Escherichia coli, and Candida albicans, with MIC values ranging from 64 µg/mL to 256 µg/mL.


Assuntos
Antibacterianos , Benzopiranos , Testes de Sensibilidade Microbiana , Pigmentos Biológicos , Peixe-Zebra , Animais , Benzopiranos/farmacologia , Benzopiranos/química , Benzopiranos/isolamento & purificação , Humanos , Antibacterianos/farmacologia , Antibacterianos/isolamento & purificação , Antibacterianos/química , Pigmentos Biológicos/farmacologia , Pigmentos Biológicos/isolamento & purificação , Pigmentos Biológicos/química , Staphylococcus aureus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Organismos Aquáticos , Escherichia coli/efeitos dos fármacos , China , Linhagem Celular
9.
Mar Drugs ; 22(6)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38921554

RESUMO

Five new naphthalene derivatives dalesconosides A-D, F (1-4, 6), a known synthetic analogue named dalesconoside E (5), and eighteen known compounds (7-24) were isolated from Daldinia eschscholzii MCZ-18, which is an endophytic fungus obtained from the Chinese mangrove plant Ceriops tagal. Differing from previously reported naphthalenes, compounds 1 and 2 were bearing a rare ribofuranoside substituted at C-1 and the 5-methyltetrahydrofuran-2,3-diol moiety, respectively. Their structures were determined by detailed nuclear magnetic resonance (NMR) and mass spectroscopic (MS) analyses, while the absolute configurations were established by theoretical electronic circular dichroism (ECD) calculation. Compounds 1, 3, 13-17 and 19 showed broad ranges of antimicrobial spectrum against five indicator test microorganisms (Enterococcus faecalis, Methicillin-resistant Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans); especially, 1, 16 and 17 were most potent. The variations in structure and attendant biological activities provided fresh insights concerning structure-activity relationships for the naphthalene derivatives.


Assuntos
Testes de Sensibilidade Microbiana , Naftalenos , Naftalenos/farmacologia , Naftalenos/química , Naftalenos/isolamento & purificação , Relação Estrutura-Atividade , Espectroscopia de Ressonância Magnética , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Estrutura Molecular , Rhizophoraceae/microbiologia , Endófitos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação
10.
Mar Drugs ; 22(6)2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38921589

RESUMO

Overwhelming evidence points to an aberrant Wnt/ß-catenin signaling as a critical factor in hepatocellular carcinoma (HCC) and cervical cancer (CC) pathogenesis. Dicerandrol C (DD-9), a dimeric tetrahydroxanthenone isolated from the endophytic fungus Phomopsis asparagi DHS-48 obtained from mangrove plant Rhizophora mangle via chemical epigenetic manipulation of the culture, has demonstrated effective anti-tumor properties, with an obscure action mechanism. The objective of the current study was to explore the efficacy of DD-9 on HepG2 and HeLa cancer cells and its functional mechanism amid the Wnt/ß catenin signaling cascade. Isolation of DD-9 was carried out using various column chromatographic methods, and its structure was elucidated with 1D NMR. The cytotoxicity of DD-9 on HepG2 and HeLa cells was observed with respect to the proliferation, clonality, migration, invasion, apoptosis, cell cycle, and Wnt/ß-catenin signaling cascade. We found that DD-9 treatment significantly reduced tumor cell proliferation in dose- and time-dependent manners in HepG2 and HeLa cells. The subsequent experiments in vitro implied that DD-63 could significantly suppress the tumor clonality, metastases, and induced apoptosis, and that it arrested the cell cycle at the G0/G1 phase of HepG2 and HeLa cells. Dual luciferase assay, Western blot, and immunofluorescence assay showed that DD-9 could dose-dependently attenuate the Wnt/ß-catenin signaling by inhibiting ß-catenin transcriptional activity and abrogating ß-catenin translocated to the nucleus; down-regulating the transcription level of ß-catenin-stimulated Wnt target gene and the expression of related proteins including p-GSK3-ß, ß-catenin, LEF1, Axin1, c-Myc, and CyclinD1; and up-regulating GSK3-ß expression, which indicates that DD-9 stabilized the ß-catenin degradation complex, thereby inducing ß-catenin degradation and inactivation of the Wnt/ß-catenin pathway. The possible interaction between DD-9 and ß-catenin and GSK3-ß protein was further confirmed by molecular docking studies. Collectively, DD-9 may suppress proliferation and induce apoptosis of liver and cervical cancer cells, possibly at least in part via GSK3-ß-mediated crosstalk with the Wnt/ß-catenin signaling axis, providing insights into the mechanism for the potency of DD-9 on hepatocellular and cervical cancer.


Assuntos
Apoptose , Proliferação de Células , Via de Sinalização Wnt , Humanos , Células HeLa , Apoptose/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Hep G2 , beta Catenina/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Neoplasias Hepáticas/tratamento farmacológico , Xantonas/farmacologia , Xantonas/química , Xantonas/isolamento & purificação , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Movimento Celular/efeitos dos fármacos , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/patologia
11.
Elife ; 132024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904661

RESUMO

The success of an organism depends on the molecular and ecological adaptations that promote its beneficial fitness. Parasitoids are valuable biocontrol agents for successfully managing agricultural pests, and they have evolved diversified strategies to adapt to both the physiological condition of hosts and the competition of other parasitoids. Here, we deconstructed the parasitic strategies in a highly successful parasitoid, Trichopria drosophilae, which parasitizes a broad range of Drosophila hosts, including the globally invasive species D. suzukii. We found that T. drosophilae had developed specialized venom proteins that arrest host development to obtain more nutrients via secreting tissue inhibitors of metalloproteinases (TIMPs), as well as a unique type of cell-teratocytes-that digest host tissues for feeding by releasing trypsin proteins. In addition to the molecular adaptations that optimize nutritional uptake, this pupal parasitoid has evolved ecologically adaptive strategies including the conditional tolerance of intraspecific competition to enhance parasitic success in older hosts and the obligate avoidance of interspecific competition with larval parasitoids. Our study not only demystifies how parasitoids weaponize themselves to colonize formidable hosts but also provided empirical evidence of the intricate coordination between the molecular and ecological adaptations that drive evolutionary success.


Assuntos
Adaptação Fisiológica , Drosophila , Interações Hospedeiro-Parasita , Vespas , Animais , Vespas/fisiologia , Drosophila/parasitologia , Pupa/parasitologia , Larva/parasitologia , Larva/metabolismo
12.
Transl Res ; 272: 54-67, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38838852

RESUMO

BACKGROUND: Arterial remodeling is a common pathophysiological change in the pathogenesis of cardiovascular diseases in which the phenotypic switch of vascular smooth muscle cells (VSMC) plays an important role. Recently, an increasing number of long non-coding RNAs(lncRNAs) have been shown to encode micropeptides that play biological roles and have great clinical transformation potential. However, the role of micropeptides encoded by lncRNAs in arterial remodeling has not been well studied and requires further exploration. METHODS AND RESULTS: Through bioinformatic analysis and experimental verification, we found that a new lncRNA, the mitochondrial function-related lncRNA (MFRL), encodes a 64-amino acid micropeptide, MFRLP. MFRL and MFRLP play important roles in the phenotypic switch of VSMC. Further experiments showed that MFRLP interacts with mitochondrial cytochrome b to reduce accumulation of reactive oxygen species, suppress mitophagy and inhibit the VSMC switch from contractile to synthetic phenotype. CONCLUSIONS: LncRNA MFRL encodes the micropeptide MFRLP, which interacts with mitochondrial cytochrome b to inhibit the VSMC switch from contractile to synthetic phenotype and improve arterial remodeling.

13.
RSC Adv ; 14(22): 15413-15418, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38741962

RESUMO

The urgent need to develop biocompatible, non-resistant antibacterial agents to effectively combat Gram-negative bacterial infections, particularly for the treatment of peritonitis, presents a significant challenge. In this study, we introduce our water-soluble Cu30 nanoclusters (NCs) as a potent and versatile antibacterial agent tailored for addressing peritonitis. The as-synthesized atomically precise Cu30 NCs demonstrate exceptional broad-spectrum antibacterial performance, and especially outstanding bactericidal activity of 100% against Gram-negative Escherichia coli (E. coli). Our in vivo experimental findings indicate that the Cu30 NCs exhibit remarkable therapeutic efficacy against primary peritonitis caused by E. coli infection. Specifically, the treatment leads to a profound reduction of drug-resistant bacteria in the peritoneal cavity of mice with peritonitis by more than 5 orders of magnitude, along with the resolution of pathological features in the peritoneum and spleen. Additionally, comprehensive in vivo biosafety assessment underscores the remarkable biocompatibility, low biotoxicity, as well as efficient hepatic and renal clearance of Cu30 NCs, emphasizing their potential for in vivo application. This investigation is poised to advance the development of novel Cu NC-based antibacterial agents for in vivo antibacterial treatment and the elimination of abdominal inflammation.

14.
Acta Pharmacol Sin ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719954

RESUMO

Hypertensive cerebrovascular remodeling involves the enlargement of vascular smooth muscle cells (VSMCs), which activates volume-regulated Cl- channels (VRCCs). The leucine-rich repeat-containing family 8 A (LRRC8A) has been shown to be the molecular identity of VRCCs. However, its role in vascular remodeling during hypertension is unclear. In this study, we used vascular smooth muscle-specific LRRC8A knockout (CKO) mice and an angiotensin II (Ang II)-induced hypertension model. The results showed that cerebrovascular remodeling during hypertension was ameliorated in CKO mice, and extracellular matrix (ECM) deposition was reduced. Based on the RNA-sequencing analysis of aortic tissues, the level of matrix metalloproteinases (MMPs), such as MMP-9 and MMP-14, were reduced in CKO mice with hypertension, which was further verified in vivo by qPCR and immunofluorescence analysis. Knockdown of LRRC8A in VSMCs inhibited the Ang II-induced upregulation of collagen I, fibronectin, and matrix metalloproteinases (MMPs), and overexpression of LRRC8A had the opposite effect. Further experiments revealed an interaction between with-no-lysine (K)-1 (WNK1), which is a "Cl--sensitive kinase", and Forkhead transcription factor O3a (FOXO3a), which is a transcription factor that regulates MMP expression. Ang II induced the phosphorylation of WNK1 and downstream FOXO3a, which then increased the expression of MMP-2 and MMP-9. This process was inhibited or potentiated when LRRC8A was knocked down or overexpressed, respectively. Overall, these results demonstrate that LRRC8A knockout in vascular smooth muscle protects against cerebrovascular remodeling during hypertension by reducing ECM deposition and inhibiting the WNK1/FOXO3a/MMP signaling pathway, demonstrating that LRRC8A is a potential therapeutic target for vascular remodeling-associated diseases such as stroke.

15.
Insects ; 15(5)2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38786908

RESUMO

Parasitoids commonly manipulate their host's metabolism and immunity to facilitate their offspring survival, but the mechanisms remain poorly understood. Here, we deconstructed the manipulation strategy of a newly discovered parasitoid wasp, L. myrica, which parasitizes D. melanogaster. Using RNA-seq, we analyzed transcriptomes of L. myrica-parasitized and non-parasitized Drosophila host larvae. A total of 22.29 Gb and 23.85 Gb of clean reads were obtained from the two samples, respectively, and differential expression analysis identified 445 DEGs. Of them, 304 genes were upregulated and 141 genes were downregulated in parasitized hosts compared with non-parasitized larvae. Based on the functional annotations in the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases, we found that the genes involved in host nutrition metabolism were significantly upregulated, particularly in carbohydrate, amino acid, and lipid metabolism. We also identified 30 other metabolism-related DEGs, including hexokinase, fatty acid synthase, and UDP-glycosyltransferase (Ugt) genes. We observed that five Bomanin genes (Boms) and six antimicrobial peptides (AMPs) were upregulated. Moreover, a qRT-PCR analysis of 12 randomly selected DEGs confirmed the reproducibility and accuracy of the RNA-seq data. Our results provide a comprehensive transcriptomic analysis of how L. myrica manipulates its host, laying a solid foundation for studies on the regulatory mechanisms employed by parasitoid wasps in their hosts.

16.
Opt Express ; 32(7): 12172-12180, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571048

RESUMO

A narrow-linewidth and low relative intensity noise (RIN) Tm/Ho co-doped fiber laser based on a saturable absorber and self-injection locking was demonstrated for the first time. Utilizing self-injection locking technology, the frequency noise power spectral density is remarkably reduced by more than 17.1 dB from 1.21 × 106 Hz2/Hz to 7.30 × 103 Hz2/Hz when the frequency is approximately 1 kHz. Furthermore, a laser with a linewidth compressed to a quarter of the original linewidth from 44.386 kHz to 2.850 kHz, a RIN of less than -127.74 dB/Hz, and an optical signal-to-noise ratio of more than 71.6 dB can be obtained. Using a delay fiber, the relaxation oscillation peak frequencies move to lower frequencies, from 27.9 kHz to 15.8 kHz. The proposed laser is highly competitive in advanced coherent light detection fields, including coherent Doppler wind lidar, high-speed coherent optical communication, and precise absolute distance coherent measurement.

17.
Nano Lett ; 24(18): 5631-5638, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38669049

RESUMO

Perovskite light-emitting diodes (PeLEDs) based on CsPb(Br/I)3 nanocrystals (NCs) usually suffer from severe spectral instability under operating voltage due to the poor-quality PeNCs. Herein, zeolite was utilized to prepare high-quality CsPb(Br/I)3 NCs via promoting the homogeneous nucleation and growth and suppressing the Ostwald ripening of PeNCs. In addition, the decomposed zeolite interacted strongly with PeNCs through Pb-O bonds and hydrogen bonds, which inhibited the formation of defects and suppressed halide ion migration, leading to an improved photoluminescence quantum yield (PLQY) and enhanced stability of PeNCs. Moreover, the strong binding affinity of decomposed zeolite to PeNCs contributed to the formation of homogeneous perovskite films with high PLQY. As a result, pure-red PeLEDs with Commission International de I'Eclairage (CIE) coordinates of (0.705, 0.291) were fabricated, approaching the Rec. 2020 red primary color. The devices achieved a peak external quantum efficiency of 23.0% and outstanding spectral stability.

18.
Anal Chim Acta ; 1305: 342588, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38677842

RESUMO

BACKGROUND: Sulfur dioxide (SO2) is a significant gas signaling molecule in organisms, and viscosity is a crucial parameter of the cellular microenvironment. They are both involved in regulating many physiological processes in the human body. However, abnormalities in SO2 and viscosity levels are associated with various diseases, such as cardiovascular disease, lung cancer, respiratory diseases, neurological disorders, diabetes and Alzheimer's disease. Hence, it is essential to explore novel and efficient fluorescent probes for simultaneously monitoring SO2 and viscosity in organisms. RESULTS: We selected quinolinium salt with good stability, high fluorescence intensity, good solubility and low cytotoxicity as the fluorophore and developed a highly sensitive ratiometric probe QQD to identify SO2 and viscosity changes based on Förster resonance energy transfer/twisted intramolecular charge transfer (FRET/TICT) mechanism. Excitingly, compared with other probes for SO2 detection, QQD not only identified HSO3-/SO32- with a large Stokes shift (218 nm), low detection limit (1.87 µM), good selectivity, high energy transfer efficiency (92 %) and wide recognition range (1.87-200 µM), but also identified viscosity with a 26-fold fluorescence enhancement and good linearity. Crucially, QQD was applied to detect HSO3-/SO32- and viscosity in actual water and food samples. In addition, QQD had low toxicity and good photostability for imaging HSO3-/SO32- and viscosity in cells. These results confirmed the feasibility and reliability of QQD for HSO3-/SO32- and viscosity imaging and environmental detection. SIGNIFICANCE: We reported a unique ratiometric probe QQD for detecting HSO3-/SO32- and viscosity based on the quinolinium skeleton. In addition to detecting HSO3-/SO32- and viscosity change in actual water and food samples, QQD could also monitor the variations of HSO3-/SO32- and viscosity in cells, which provided an experimental basis for further exploration of the role of SO2 derivatives and viscosity in biological systems.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Viscosidade , Humanos , Dióxido de Enxofre/análise , Sulfitos/análise , Sulfitos/química , Limite de Detecção , Compostos de Quinolínio/química
19.
Talanta ; 275: 126135, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677165

RESUMO

Hydrogen peroxide (H2O2) and viscosity play vital roles in the cellular environment as signaling molecule and microenvironment parameter, respectively, and are associated with many physiological and pathological processes in biological systems. We developed a near-infrared fluorescent probe, CQ, which performed colorimetric and ratiometric detection of H2O2 and viscosity based on the FRET mechanism, and was capable of monitoring changes in viscosity and H2O2 levels simultaneously through two different channels. Based on the specific reaction of H2O2 with borate ester, CQ exhibited a significant ratiometric response to H2O2 with a large Stokes shift of 221 nm, a detection limit of 0.87 µM, a near-infrared emission wavelength of 671 nm, a response time of 1 h, a wide detection ranges of 0.87-800 µM and a high energy transfer efficiency of 99.9 %. CQ could also recognize viscosity by the TICT mechanism, and efficiently detect viscosity changes caused by food thickeners. More importantly, CQ could successfully detect endogenous/exogenous H2O2 and viscosity in live HeLa cells, which was expected to be a practical tool for detecting H2O2 and viscosity in live cells.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes , Peróxido de Hidrogênio , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Corantes Fluorescentes/química , Humanos , Células HeLa , Transferência Ressonante de Energia de Fluorescência/métodos , Viscosidade , Raios Infravermelhos , Limite de Detecção , Sobrevivência Celular
20.
J Agric Food Chem ; 72(20): 11503-11514, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38634424

RESUMO

The fruits of Rosa roxburghii Tratt. are edible nutritional food with high medicinal value and have been traditionally used as Chinese folk medicine for a long time. In this study, 26 triterpenoids including four new pentacyclic triterpenoids, roxbuterpenes A-D (1, 4, 5, and 24), along with 22 known analogues (2, 3, 6-23, 25, and 26), were isolated from the fruits of R. roxburghii. Their chemical structures were determined on the basis of extensive spectroscopic analyses (including IR, HRESIMS and NMR spectroscopy). The absolute configuration of roxbuterpene A (1) was determined by an X-ray crystallographic analysis. This is the first report of the crystal structure of 5/6/6/6/6-fused system pentacyclic triterpenoid. Notably, roxbuterpenes A and B (1 and 4) possessed the A-ring contracted triterpenoid and nortriterpenoid skeletons with a rare 5/6/6/6/6-fused system, respectively. Compounds 1-7, 11, 13-15, 18-20, 24, and 25 exhibited moderate or potent inhibitory activities against α-glucosidase. Compounds 2, 4, 6, 11, and 14 showed strong activities against α-glucosidase with IC50 values of 8.4 ± 1.6, 7.3 ± 2.2, 13.6 ± 1.4, 0.9 ± 0.4, and 12.5 ± 2.4 µM, respectively (positive control acarbose, 10.1 ± 0.8 µM). Compounds 13, 14, and 16 moderately inhibited the release of NO (nitric oxide) with IC50 values ranging from 25.1 ± 2.0 to 51.4 ± 3.1 µM. Furthermore, the expressions of TNF-α (tumor necrosis factor-α) and IL-6 (interleukin-6) were detected by ELISA (enzyme-linked immunosorbent assay), and compounds 13, 14, and 16 exhibited moderate inhibitory effects on TNF-α and IL-6 release in a dose-dependent manner ranging from 12.5 to 50 µM.


Assuntos
Anti-Inflamatórios , Frutas , Inibidores de Glicosídeo Hidrolases , Rosa , Triterpenos , alfa-Glucosidases , Animais , Camundongos , alfa-Glucosidases/metabolismo , alfa-Glucosidases/química , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Frutas/química , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Interleucina-6/genética , Interleucina-6/metabolismo , Interleucina-6/imunologia , Estrutura Molecular , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7 , Rosa/química , Triterpenos/química , Triterpenos/farmacologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/imunologia
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