Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 330
Filtrar
1.
Nature ; 618(7963): 80-86, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36990110

RESUMO

All-perovskite tandem solar cells provide high power conversion efficiency at a low cost1-4. Rapid efficiency improvement in small-area (<0.1 cm2) tandem solar cells has been primarily driven by advances in low-bandgap (approximately 1.25 eV) perovskite bottom subcells5-7. However, unsolved issues remain for wide-bandgap (> 1.75 eV) perovskite top subcells8, which at present have large voltage and fill factor losses, particularly for large-area (>1 cm2) tandem solar cells. Here we develop a self-assembled monolayer of (4-(7H-dibenzo[c,g]carbazol-7-yl)butyl)phosphonic acid as a hole-selective layer for wide-bandgap perovskite solar cells, which facilitates subsequent growth of high-quality wide-bandgap perovskite over a large area with suppressed interfacial non-radiative recombination, enabling efficient hole extraction. By integrating (4-(7H-dibenzo[c,g]carbazol-7-yl)butyl)phosphonic acid in devices, we demonstrate a high open-circuit voltage (VOC) of 1.31 V in a 1.77-eV perovskite solar cell, corresponding to a very low VOC deficit of 0.46 V (with respect to the bandgap). With these wide-bandgap perovskite subcells, we report 27.0% (26.4% certified stabilized) monolithic all-perovskite tandem solar cells with an aperture area of 1.044 cm2. The certified tandem cell shows an outstanding combination of a high VOC of 2.12 V and a fill factor of 82.6%. Our demonstration of the large-area tandem solar cells with high certified efficiency is a key step towards scaling up all-perovskite tandem photovoltaic technology.

2.
J Neurosci ; 43(16): 2907-2920, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-36868854

RESUMO

General anesthesia shares many similarities with natural sleep in behavior and electroencephalogram (EEG) patterns. The latest evidence suggests that general anesthesia and sleep-wake behavior may share overlapping neural substrates. The GABAergic neurons in the basal forebrain (BF) have recently been demonstrated to play a key role in controlling wakefulness. It was hypothesized that BF GABAergic neurons may participate in the regulation of general anesthesia. Here, using in vivo fiber photometry, we found that the activity of BF GABAergic neurons was generally inhibited during isoflurane anesthesia, having obviously decreased during the induction of anesthesia and being gradually restored during the emergence from anesthesia, in Vgat-Cre mice of both sexes. Activation of BF GABAergic neurons with chemogenetic and optogenetic approaches decreased sensitivity to isoflurane, delayed induction, and accelerated emergence from isoflurane anesthesia. Optogenetic activation of BF GABAergic neurons decreased EEG δ power and the burst suppression ratio (BSR) during 0.8% and 1.4% isoflurane anesthesia, respectively. Similar to the effects of activating BF GABAergic cell bodies, photostimulation of BF GABAergic terminals in the thalamic reticular nucleus (TRN) also strongly promoted cortical activation and behavioral emergence from isoflurane anesthesia. Collectively, these results showed that the GABAergic BF is a key neural substrate for general anesthesia regulation that facilitates behavioral and cortical emergence from general anesthesia via the GABAergic BF-TRN pathway. Our findings may provide a new target for attenuating the depth of anesthesia and accelerating emergence from general anesthesia.SIGNIFICANCE STATEMENT The basal forebrain (BF) is a key brain region controlling sleep-wake behavior. Activation of GABAergic neurons in the BF potently promotes behavioral arousal and cortical activity. Recently, many sleep-wake-related brain structures have been reported to participate in the regulation of general anesthesia. However, it is still unclear what role BF GABAergic neurons play in general anesthesia. In this study, we aim to reveal the role of BF GABAergic neurons in behavioral and cortical emergence from isoflurane anesthesia and elucidate the underlying neural pathways. Understanding the specific role of BF GABAergic neurons in isoflurane anesthesia would improve our understanding of the mechanisms of general anesthesia and may provide a new strategy for accelerating emergence from general anesthesia.


Assuntos
Prosencéfalo Basal , Isoflurano , Masculino , Feminino , Camundongos , Animais , Isoflurano/farmacologia , Prosencéfalo Basal/fisiologia , Neurônios GABAérgicos/fisiologia , Sono/fisiologia , Eletroencefalografia , Anestesia Geral
3.
J Am Chem Soc ; 146(2): 1262-1268, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38180776

RESUMO

A concise enantioselective total synthesis of (-)-daphenylline, a hexacyclic Daphniphyllum alkaloid with a unique benzene ring, was achieved in 14 steps. The synthesis commences with two chiral stereocenters, C2 and C18, readily installed via Carreira's Ir/amine dual-catalyzed allylation. The allylic bridgehead amine 6 was rapidly prepared through Wickens' photoredox-catalyzed hydrocarboxylation of olefin and CuBr2-catalyzed α-amination of ketone. The tetracycle 4 was formed via Pd-catalyzed reductive Heck reaction or, more concisely, by Krische's Rh-catalyzed reductive 1,6-enyne cyclization. In this synthesis, newly reported Wickens' photoredox-catalyzed hydrocarboxylation was used twice, and Friedel-Crafts acylation thrice.

4.
Small ; 20(13): e2307298, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37972284

RESUMO

As the electron transport layer in quantum dot light-emitting diodes (QLEDs), ZnO suffers from excessive electrons that lead to luminescence quenching of the quantum dots (QDs) and charge-imbalance in QLEDs. Therefore, the interplay between ZnO and QDs requires an in-depth understanding. In this study, DFT and COSMOSL simulations are employed to investigate the effect of sulfur atoms on ZnO. Based on the simulations, thiol ligands (specifically 2-hydroxy-1-ethanethiol) to modify the ZnO nanocrystals are adopted. This modification alleviates the excess electrons without causing any additional issues in the charge injection in QLEDs. This modification strategy proves to be effective in improving the performance of red-emitting QLEDs, achieving an external quantum efficiency of over 23% and a remarkably long lifetime T95 of >12 000 h at 1000 cd m-2. Importantly, the relationship between ZnO layers with different electronic properties and their effect on the adjacent QDs through a single QD measurement is investigated. These findings show that the ZnO surface defects and electronic properties can significantly impact the device performance, highlighting the importance of optimizing the ZnO-QD interface, and showcasing a promising ligand strategy for the development of highly efficient QLEDs.

5.
J Ren Nutr ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848805

RESUMO

OBJECTIVES: Nutrition labeling is important to guide patients with chronic kidney disease to make informed choices. This study aimed to evaluate the extent and accessibility of nutrition labeling for sodium, potassium, and phosphorus on food and beverage products in a supermarket. METHODS: A cross-sectional survey was conducted in a Malaysian supermarket. Information on sodium, potassium, and phosphorus contents was collected from the nutrition fact panel, while information on food additives containing sodium, potassium, and phosphorus was collected from the ingredient list. RESULTS: The survey included 2,577 foods and beverages, and 79.4% of the products included sodium information in nutrition fact panels, but only 11.7% and 2.0% disclosed potassium and phosphorus content, respectively. Sodium-containing additives were found in 78.6% of products; potassium- and phosphorus-containing additives were reported in 28.5% and 46.9% of products, respectively. Sodium-containing additives were typically listed as "salt," potassium-containing additives as "alternative names," and phosphorus-containing additives as "starch" and "E numbers." Imported products were more likely to include sodium (P < .001) and phosphorus (p = .036) contents, while more locally manufactured products reported sodium- (p = .003) and phosphorus- (P = .004) containing additives. CONCLUSION: There is limited availability of potassium and phosphorus information on nutrition labels in Malaysia food and beverage products, which presents significant challenges for individuals with chronic kidney disease in choosing appropriate products for their dietary needs.

6.
Ecotoxicol Environ Saf ; 279: 116489, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38776781

RESUMO

Combined toxicity is a critical concern during the risk assessment of environmental pollutants. Due to the characteristics of strong hydrophobicity and large specific surface area, microplastics (MPs) and nanoplastics (NPs) have become potential carriers of organic pollutants that may pose a health risk to humans. The co-occurrence of organic pollutants and MPs would cause adverse effects on aquatic organism, while the information about combined toxicity induced by organophosphorus flame retardants and MPs on human cells was limited. This study aimed to reveal the toxicity effects of co-exposure to triphenyl phosphate (TPHP) and polystyrene (PS) particles with micron-size/nano-size on HepG2 cell line. The adsorption behaviors of TPHP on PS particles was observed, with the PS-NP exhibiting a higher adsorption capacity. The reactive oxygen species generation, mitochondrial membrane potential depolarization, lactate dehydrogenase release and cell apoptosis proved that PS-NPs/MPs exacerbated TPHP-induced cytotoxicity. The particle size of PS would affect the toxicity to HepG2 cells that PS-NP (0.07 µm) exhibited more pronounced combined toxicity than PS-MP (1 µm) with equivalent concentrations of TPHP. This study provides fundamental insights into the co-toxicity of TPHP and PS micro/nanoplastics in HepG2 cells, which is crucial for validating the potential risk of combined toxicity in humans.


Assuntos
Apoptose , Retardadores de Chama , Potencial da Membrana Mitocondrial , Microplásticos , Nanopartículas , Poliestirenos , Espécies Reativas de Oxigênio , Humanos , Células Hep G2 , Poliestirenos/toxicidade , Poliestirenos/química , Nanopartículas/toxicidade , Nanopartículas/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Retardadores de Chama/toxicidade , Microplásticos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Tamanho da Partícula , Organofosfatos/toxicidade , Poluentes Químicos da Água/toxicidade , Adsorção , Plásticos/toxicidade
7.
Mikrochim Acta ; 191(6): 351, 2024 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806809

RESUMO

A target-triggered strand displacement-assisted target recycling based on carbon dots-based fluorescent probe and mesoporous silica nanoparticles@polydopamine (MSNs@PDA) was established to detect miRNA. The surface of MSNs rich in mesopores was coated with a layer of PDA, which can adsorb and quench the fluorescence of single-stranded Fuel DNA with fluorescent carbon dots (CDs) modified at the end through fluorescence resonance energy transfer (FRET). After adding double-stranded DNA-gold nanoparticles (dsDNA-AuNPs) and target let-7a, it will trigger two toehold-mediated strand displacement reactions (TSDR), leading to the recovery of fluorescence and the recycling of target let-7a (excitation wavelength: 380 nm; emission wavelength: 458 nm). The recovery value of fluorescence is proportional to the logarithm of the target microRNA let-7a concentration, thus realizing the sensitivity amplification detection of disease markers. The MSNs@PDA@Fuel DNA-CDs/dsDNA-AuNPs nanoplatform based on the strategy of "on-off-on" and TSDR cyclic amplification may hold great potential as an effective and safe nanoprobe for accurate fluorescence imaging of diseases related to miRNA with low abundances.


Assuntos
Carbono , Corantes Fluorescentes , Ouro , Indóis , MicroRNAs , Polímeros , Pontos Quânticos , Dióxido de Silício , MicroRNAs/análise , Corantes Fluorescentes/química , Carbono/química , Humanos , Pontos Quânticos/química , Polímeros/química , Ouro/química , Dióxido de Silício/química , Indóis/química , Transferência Ressonante de Energia de Fluorescência/métodos , Nanopartículas Metálicas/química , Imagem Óptica/métodos , Limite de Detecção , Porosidade , DNA/química
8.
J Neuroinflammation ; 20(1): 91, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37029422

RESUMO

BACKGROUND: Retinal ischemia-reperfusion (RIR) injury refers to an obstruction in the retinal blood supply followed by reperfusion. Although the molecular mechanism underlying the ischemic pathological cascade is not fully understood, neuroinflammation plays a crucial part in the mortality of retinal ganglion cells. METHODS: Single-cell RNA sequencing (scRNA-seq), molecular docking, and transfection assay were used to explore the effectiveness and pathogenesis of N,N-dimethyl-3ß-hydroxycholenamide (DMHCA)-treated mice with RIR injury and DMHCA-treated microglia after oxygen and glucose deprivation/reoxygenation (OGD/R). RESULTS: DMHCA could suppress inflammatory gene expression and attenuate neuronal lesions, restoring the retinal structure in vivo. Using scRNA-seq on the retina of DMHCA-treated mice, we provided novel insights into RIR immunity and demonstrated nerve injury-induced protein 1 (Ninjurin1/Ninj 1) as a promising treatment target for RIR. Moreover, the expression of Ninj1, which was increased in RIR injury and OGD/R-treated microglia, was downregulated in the DMHCA-treated group. DMHCA suppressed the activation of the nuclear factor kappa B (NF-κB) pathways induced by OGD/R, which was undermined by the NF-κB pathway agonist betulinic acid. Overexpressed Ninj1 reversed the anti-inflammatory and anti-apoptotic function of DMHCA. Molecular docking indicated that for Ninj1, DMHCA had a low binding energy of - 6.6 kcal/mol, suggesting highly stable binding. CONCLUSION: Ninj1 may play a pivotal role in microglia-mediated inflammation, while DMHCA could be a potential treatment strategy against RIR injury.


Assuntos
NF-kappa B , Traumatismo por Reperfusão , Camundongos , Animais , NF-kappa B/metabolismo , Transdução de Sinais , Simulação de Acoplamento Molecular , Oxigênio , Células Ganglionares da Retina/patologia , Traumatismo por Reperfusão/metabolismo , Inflamação/tratamento farmacológico , Fatores de Crescimento Neural , Moléculas de Adesão Celular Neuronais
9.
Toxicol Appl Pharmacol ; 479: 116729, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37863360

RESUMO

Cancer cachexia is a systemic metabolic disorder syndrome characterized by severe wasting of muscle and adipose tissues while is lack of effective therapeutic approaches. Carnosol (CS) was found in our previous study to exhibit ameliorating effects on cancer cachexia. In the present study, we designed and synthesized 49 CS analogues by structural modification of CS. Results of activity screening revealed that, among the analogues, WK-63 exhibited better effects than CS in ameliorating atrophy of C2C12 myotubes induced by conditioned medium of C26 tumor cells. WK-63 could also dose-dependently alleviate adipocyte lipolysis of mature 3 T3-L1 cells induced by C26 tumor cell conditioned medium. WK-63 alleviated myotube atrophy by inhibiting Nuclear Factor kappa-B (NF-κB) and activating the Protein Kinase B (AKT) signaling pathway, and also alleviated fat loss by inhibiting NF-κB and Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) signaling pathways. Results of pharmacokinetic (PK) assay showed that, compared with other analogues, WK-63 exhibited longer half-life (T1/2) and mean residence time (MRTs), as well as a larger concentration curve area (AUC0-t). These findings suggested that WK-63 might exert optimal effects in vivo. In the C26 tumor-bearing mice model, administration of WK-63 ameliorated the body weight loss and also improved the weight loss of epididymal adipose tissue. WK-63 is expected to be a novel therapeutic option for the treatment of cancer cachexia.


Assuntos
NF-kappa B , Neoplasias , Camundongos , Animais , NF-kappa B/metabolismo , Caquexia/tratamento farmacológico , Caquexia/etiologia , Caquexia/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Neoplasias/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Atrofia/patologia , Adipócitos/metabolismo , Músculo Esquelético , Atrofia Muscular/tratamento farmacológico
10.
Langmuir ; 39(18): 6455-6465, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37092960

RESUMO

Pickering emulsions indicate stronger resistance against droplet coalescence than the surfactant-stabilized emulsions. To resemble the surfactant amphiphilicity, Janus fiber fragments (JFs) were herein prepared through side-by-side electrospinning of poly(styrene-maleic anhydride) (PSMA) derivatives and cryosection of the aligned fibers, followed by conjugation of hydrophobic cetylamine (C16) and hydrophilic poly(N-isopropylacrylamide) (PNIPAm) ligands on the separate sides. Orthogonal analysis table L25(56) was designed to examine the effect of process parameters on the emulsification efficiency and stability index of Pickering emulsions. The emulsification efficiency is dominated by the JF concentration and length, while the emulsion stability could be prolonged through adjusting the JF concentration and hydrophilic graft density. JF-stabilized emulsions exhibit a much higher stability index (96.4%) than that of Janus microparticle counterparts (37.7%). Though there is no apparent effect on the surface wettability, JFs with PNIPAm grafts of about 2200 Da achieve the most stable Pickering emulsions. Superparamagnetic Fe3O4 nanoparticles are inoculated into JFs to collect emulsion droplets under a magnetic field, and the emulsions could be demulsified at an elevated temperature to harvest oil. Meanwhile, the recovered JF emulsifiers could be repeatedly used without loss of the emulsification efficiency. Thus, this study demonstrates surface-switchable JFs to be effective stabilizers of Pickering emulsions and readily recycled for oil harvesting from wastewater.

11.
Sensors (Basel) ; 23(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37960543

RESUMO

The rapid detection of distracted driving behaviors is crucial for enhancing road safety and preventing traffic accidents. Compared with the traditional methods of distracted-driving-behavior detection, the YOLOv8 model has been proven to possess powerful capabilities, enabling it to perceive global information more swiftly. Currently, the successful application of GhostConv in edge computing and embedded systems further validates the advantages of lightweight design in real-time detection using large models. Effectively integrating lightweight strategies into YOLOv8 models and reducing their impact on model performance has become a focal point in the field of real-time distracted driving detection based on deep learning. Inspired by GhostConv, this paper presents an innovative GhostC2f design, aiming to integrate the idea of linear transformation to generate more feature maps without additional computation into YOLOv8 for real-time distracted-driving-detection tasks. The goal is to reduce model parameters and computational load. Additionally, enhancements have been made to the path aggregation network (PAN) to amplify multi-level feature fusion and contextual information propagation. Furthermore, simple attention mechanisms (SimAMs) are introduced to perform self-normalization on each feature map, emphasizing feature maps with valuable information and suppressing redundant information interference in complex backgrounds. Lastly, the nine distinct distracted driving types in the publicly available SFDDD dataset were expanded to 14 categories, and nighttime scenarios were introduced. The results indicate a 5.1% improvement in model accuracy, with model weight size and computational load reduced by 36.7% and 34.6%, respectively. During 30 real vehicle tests, the distracted-driving-detection accuracy reached 91.9% during daylight and 90.3% at night, affirming the exceptional performance of the proposed model in assisting distracted driving detection when driving and contributing to accident-risk reduction.

12.
Zhonghua Nan Ke Xue ; 29(1): 54-59, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-37846833

RESUMO

OBJECTIVE: To investigate the correlation of frailty with ED in Chinese elderly men. METHODS: This community-based study was conducted with a sample of 258 Chinese men aged 60 to 83 years old in Fuyang City, Anhui Province. All the participants completed a standard questionnaire on demographics, lifestyle, underlying diseases and medical and sexual histories. They also scored on the Chinese version of Tilburg Frailty Indicator (TFI) and International Index of Erectile Function-5 (IIEF-5). RESULTS: The incidence rates of ED and frailty in the elderly men were 85.27% and 75.58%, respectively. The ED patients, compared with the non-ED males, had a significantly older age (ï¼»71.25 ± 5.83ï¼½ vs ï¼»66.92 ± 5.44ï¼½ yr, P < 0.01) and higher body mass index (ï¼»24.37 ± 3.31ï¼½ vs ï¼»23.35 ± 2.97ï¼½ kg/m 2, P < 0.05), incidence of diabetes mellitus (38.0% vs 19.2%, P < 0.05) and TFI scores (8.61 ± 4.29 vs 5.95 ± 4.36, P < 0.05), but lower education and frequency of irregular intercourse (less than once a week) (all P<0.05). Multivariate analysis indicated that diabetes (OR:3.292,95% CI:1.236-8.768), irregular intercourse (OR:2.425,95% CI:1.114-5.279), and scores of frailty (OR:4.502,95% CI:1.905-10.640) were regarded as independent risk factors for ED (all P < 0.05). CONCLUSION: There is a strong correlation between ED and frailty in elderly men. Sexual health care for elderly ED patients should be more focused on the multidimensional assessment and treatment of senile frailty.


Assuntos
Diabetes Mellitus , Disfunção Erétil , Fragilidade , Idoso , Masculino , Humanos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Disfunção Erétil/epidemiologia , Disfunção Erétil/etiologia , Fragilidade/epidemiologia , Fragilidade/complicações , Envelhecimento , Comportamento Sexual , Inquéritos e Questionários
13.
Zhongguo Zhong Yao Za Zhi ; 48(1): 30-38, 2023 Jan.
Artigo em Zh | MEDLINE | ID: mdl-36725255

RESUMO

Rare and endangered Chinese medicinal materials are the material basis for innovation and development of Chinese medicinal materials and their curative effects are remarkable. However, the resources are in shortage due to various man-made or natural factors such as rising demand, overexploitation and environmental degradation. Therefore, finding alternatives is a feasible and effective solution. This study systematically sorted out the list of rare and endangered Chinese medicinal materials, and combed relevant policies and regulations. According to existing research, the substitution model of rare and endangered Chinese medicinal materials was constructed from the theoretical level. In view of the slow search for substitutes, the failure to follow the basic theory of traditional Chinese medicine in the process of research and development, the difficulty in breaking through technologies and the incomplete guarantee of the clinical efficacy of substitutes, a multi-component replacement was proposed to replace the originals with more effective components from a wide range of sources. This study was expected to promote the study on the substitutes of rare and endangered Chinese medicinal materials to step into a new stage.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Projetos de Pesquisa , Medicina Tradicional Chinesa , Tecnologia
14.
BMC Genomics ; 23(1): 764, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36414988

RESUMO

BACKGROUND: Rectal cancer (RC) is one of the most common malignant tumors. Ferroptosis is an iron-dependent form of cell death, which plays an important role in various cancers. However, the correlation between ferroptosis-related genes (FRGs) and prognosis in RC remains unclear. METHODS: Gene expression data from The Cancer Genome Atlas Rectum adenocarcinoma (TCGA-READ) and GSE87211 were downloaded. Clustering and functional enrichment were evaluated. A FRGs risk score was established based on the univariate Cox analysis and the Least absolute shrinkage and selection operator (LASSO) analysis. K-M analysis and ROC analysis were conducted to determine prognostic values. qRT-PCR was performed to validate levels of mRNA expression. Multivariate Cox analysis was used to build a prognostic prediction model based on the risk score. RESULTS: Based on FRGs, RC patients were grouped into two clusters. In the functional enrichment of differentially expressed genes between the two clusters, immune-related pathways dominated. A novel FRGs signature with 14 genes related to the overall survival (OS) of RC was established. qRT-PCR of the 14 genes identified TP63, ISCU, PLIN4, MAP3K5, OXSR, FANCD2 and ATM were overexpressed in RC tissue; HSPB1, MAPK1, ABCC1, PANX1, MAPK9 and ATG7 were underexpressed; TUBE1 had no difference. The high-risk group had a significantly lower OS than the low-risk group (P < 0.001), and ROC curve analysis confirmed the signature's predictive capacity. Multivariate analysis demonstrated that the risk score and age were independent prognostic factors. CONCLUSION: A novel FRGs model can be used to predict the prognosis in RC, as well as to guide individual treatment.


Assuntos
Ferroptose , Neoplasias Retais , Humanos , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Ferroptose/genética , Regulação Neoplásica da Expressão Gênica , Prognóstico , Neoplasias Retais/genética
15.
Opt Lett ; 47(6): 1545-1548, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290360

RESUMO

We demonstrate a wavelength-tunable, sub-200 fs, and watt-level thulium-doped ultrafast fiber oscillator with a fundamental frequency repetition rate of 509.7 MHz. The wavelength can be tuned between 1918.5 nm and 2031 nm by adjusting the intra-cavity waveplates. When the wavelength is tuned to below 2000 nm, the average output power exceeds 1 W. The oscillator provides a maximum average power of 1.314 W (corresponding to a pulse energy of 2.58 nJ) and a highest peak power of 12.5 kW at 1940 nm. Such a high-power, tunable 2-µm mode-locked fiber laser is an ideal light source candidate for a variety of applications, such as frequency metrology, molecular spectroscopy, and ultrafast pump-probe spectroscopy.

16.
Opt Lett ; 47(19): 4893-4896, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36181144

RESUMO

We report a mode-locked high-power all-polarization-maintaining Er/Yb-doped large-mode-area fiber oscillator based on a bias nonlinear amplifying loop mirror (NALM). The oscillator can generate ∼1-nJ femtosecond pulses without dispersion compensation. By inserting a Martinez-type compensator to provide normal dispersion, it can generate >10-nJ picosecond dissipative solitons (DSs). The measured M2 factors are below 1.5, indicating a good beam quality. When the cavity dispersion is tuned to be ∼0.704 ps2, the oscillator can deliver chirped DSs with an average power as high as 690 mW at a repetition rate of 49.86 MHz, corresponding to a pulse energy of ∼13.8 nJ. The pulse after compression has a near Fourier-limited width of ∼2 ps. Successful demonstration of this laser provides a robust scheme for improving the performance of ultrafast fiber lasers in average power and pulse energy.

17.
J Fluoresc ; 32(3): 1005-1017, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35247130

RESUMO

Spectroscopic (FT-IR, FT-Raman, UV-vis, and NMR) techniques have been extensively used for structural elucidation of compounds along with the study of geometrical and vibrational properties. Herein, 2-acetyl-5-methylfuran, a derivative of furan, was experimentally characterized and analyzed in details using FT-IR, FT-Raman, UV-vis, and 1H NMR spectroscopic techniques conducted in different solvents. The experimentally analyzed spectral results were carefully compared with theoretical values obtained using density functional theory (DFT) calculations at the B3LYP/6-311 + + G (d, p) method to support, validate, and provide more insights on the structural characterizations of the titled compound. The correlated experimental and theoretical structural vibrational assignments along with their potential energy distributions (PEDs) and all the spectroscopic spectral investigations of the titled structure were observed to be in good agreements with calculated results.

18.
BMC Surg ; 22(1): 43, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35120483

RESUMO

BACKGROUND: Transanal endoscopic microsurgery (TEM) has been accepted worldwide for the treatment of local rectal lesions. We aimed to assess the efficacy and safety of TEM in the treatment of rectal neuroendocrine tumors (RNET). METHODS: A retrospective study of patients who had undergone TEM for RNET at our institution between December 2006 and June 2019 was performed. Demographic and tumor characteristics, operative and pathological details, complications, anal function questionnaires, and follow-up data were included. RESULTS: A total of 144 patients was included. TEM was performed as primary excision in 54 patients, after endoscopic forceps biopsy in 57 patients, and after incomplete resection by endoscopic excision in 33 patients. The median size of all primary tumors was 0.6 cm (range, 0.3-2.0 cm), and the negative resection margin was achieved in 142 (98.6%) patients. Postoperative complications (referring to only bleeding) occurred in 3 (2.1%) patients and was successfully managed with conservative method. After a median follow-up of 75.5 months after surgery, 3 patients died of other causes, and 2 patients suffered metastasis. An anal function questionnaire was posted 24 months after TEM. Among the results, 3 (2.1%) patients complained of major low anterior resection syndrome (LARS), including 1 (0.7%) who suffered from complete incontinence, while 6 (4.2%) patients had minor LARS. CONCLUSIONS: TEM has satisfying long-term outcomes and relatively low anal function disturbance as for the treatment of small RNET. TEM also acts as a preferred salvage treatment for incomplete endoscopic excision.


Assuntos
Tumores Neuroendócrinos , Neoplasias Retais , Microcirurgia Endoscópica Transanal , Humanos , Microcirurgia , Tumores Neuroendócrinos/cirurgia , Complicações Pós-Operatórias/epidemiologia , Neoplasias Retais/cirurgia , Estudos Retrospectivos , Síndrome , Resultado do Tratamento
19.
Molecules ; 27(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35889477

RESUMO

Xanthatin (XT) is a sesquiterpene lactone isolated from the Chinese herb Xanthium, which belongs to the Asteraceae family. In this study, we developed an inflammation model via stimulating macrophage cell line (RAW 264.7 cells) with lipopolysaccharide (LPS), which was applied to assess the anti-inflammatory effect and probable mechanisms of xanthatin. When compared with the only LPS-induced group, cells that were pretreated with xanthatin were found to decrease the amount of nitric oxide (NO), reactive oxygen species (ROS) and associated pro-inflammatory factors (TNF-α, IL-1ß and IL-6), and downregulate the mRNA expression of iNOS, COX-2, TNF-α, IL-1ß, and IL-6. Interestingly, phosphorylated levels of related proteins (STAT3, ERK1/2, SAPK/JNK, IκBα, p65) were notably increased only with the LPS-activated cells, while the expression of these could be reverted by pre-treatment with xanthatin in a dose-dependent way. Meanwhile, xanthatin was also found to block NF-κB p65 from translocating into the nucleus and activating inflammatory gene transcription. Collectively, these results demonstrated that xanthatin suppresses the inflammatory effects through downregulating the nuclear factor kappa-B (NF-κB), mitogen-activated protein kinase (MAPK) and signal transducer and activator of transcription (STATs) signaling pathways. Taken together, xanthatin possesses the potential to act as a good anti-inflammatory medication candidate.


Assuntos
Lipopolissacarídeos , NF-kappa B , Animais , Anti-Inflamatórios/uso terapêutico , Furanos , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Células RAW 264.7 , Fator de Necrose Tumoral alfa/metabolismo
20.
Molecules ; 27(19)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36234865

RESUMO

Psoriasis is a chronic inflammatory skin disorder accompanied by excessive keratinocyte proliferation. Erianin (Eri) is an ideal drug candidate for inhibiting proliferation and inducing apoptosis in the treatment of psoriasis. However, Eri's poor water solubility and low penetration activity across the skin hinder its application in local medicine. In this study, we developed a novel photo-responsive dendritic mesoporous silica nanoparticle-based carrier to deliver erianin, improved its bioavailability, and achieved sustained-release effects. Spiropyran (SP), 3-aminopropyltriethoxysilane (APTES), and perfluorodecyltriethoxysilane (PFDTES) were conjugated to the outer surface, which allowed Eri to be released in response to UV radiation. The physicochemical properties of photo-responsive dendritic mesoporous silica nanoparticles (Eri-DMSN@FSP) were characterized via multiple techniques, such as using a Fourier-transform infrared spectrometer, a high-resolution transmission electron microscope, and nuclear magnetic resonance (NMR) spectroscopy. The anti-proliferative properties and light-triggered release of erianin-loaded photo-responsive dendritic mesoporous silica nanoparticles were assessed via the MTT assay and a drug release study in vitro. Erianin-loaded photo-responsive dendritic mesoporous silica nanoparticles (UV) exhibit a significantly enhanced HaCat cell-inhibiting efficacy compared to other formulations, as demonstrated by their extremely low cell viability of 10.0% (concentration: 500 mg/mL), indicating their capability to release a drug that responds to UV radiation. The cellular uptake of photo-responsive dendritic mesoporous silica nanoparticles (DMSN@FSP) was observed via confocal laser scanning microscopy (CLSM). These experimental results show that Eri-DMSN@FSP could be effectively endocytosed into cells and respond to ultraviolet light to release Eri, achieving a more effective psoriasis treatment. Therefore, this drug delivery system may be a promising strategy for addressing the question of Eri's delivery and psoriasis therapy.


Assuntos
Dendrímeros , Nanopartículas , Psoríase , Bibenzilas , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacologia , Dendrímeros/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Humanos , Nanopartículas/química , Fenol , Porosidade , Psoríase/tratamento farmacológico , Dióxido de Silício/química , Água
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA