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1.
Nano Lett ; 24(30): 9163-9168, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39037721

RESUMO

Magneto-optical (MO) polymer nanocomposites have emerged as alternatives to conventional MO crystals, particularly in nanophotonics applications, thanks to their better processing flexibility and superior Verdet constants. However, a higher Verdet constant commonly comes with excessive optical loss due to increased absorption and scattering, resulting in a constant or reduced figure-of-merit (FOM) defined as the Verdet constant over optical loss. By doping magnetite (Fe3O4) nanoparticles with Tb3+ ions, we report a new strategy to enhance the Verdet constant without increasing the optical loss. The Fe3O4:Tb3+ nanocomposite is one of a kind that simultaneously achieves a state-of-the-art Verdet constant of 5.6 × 105 °/T·m and a state-of-the-art FOM of 31°/T in the near-infrared region.

2.
J Biol Chem ; 299(10): 105215, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37660919

RESUMO

Nuclear Factor Erythroid 2-Related Factor 2 (NRF2) is important for the expression of genes associated with oxidative stress. The levels of NRF2 are controlled by Kelch-like ECH-associated protein 1 (KEAP1)-dependent degradation. Although oxidative stress is known to suppress KEAP1 activity to stabilize the levels of NRF2, the mechanism for this control is unclear. Here, we identify that KEAP1 is modified by SUMO1 at the lysine residue position 39 (K39). Arginine replacement of this lysine (K39R) in KEAP1 did not affect its stability, subcellular localization, or dimerization but promoted the formation of the Cullin 3 ubiquitin ligase and increased NRF2 ubiquitination. This was accompanied by decreased NRF2 expression. Gene reporter assays showed that the transcription of antioxidant response elements was heightened in KEAP1-WT cells compared to cells expressing the KEAP1-K39R SUMO1 substrate mutant. Consistent with this, chromatin immunoprecipitation assays revealed higher NRF2 binding to the promoter regions of antioxidant genes in cells expressing the KEAP1-WT compared to the KEAP1-K39R mutant protein in H1299 lung cancer cell. The significance of this suppression of KEAP1 activity by its SUMOylation was tested in a subcutaneous tumor model of H1299 lung cancer cell lines that differentially expressed the WT and K39R KEAP1 constructs. This model showed that mutating the SUMOylation site on KEAP1 altered the production of reactive oxygen species and suppressed tumor growth. Taken together, our study recognizes that NRF2-dependent redox control is regulated by the SUMOylation of KEAP1. These findings identify a potential new therapeutic option to counteract oxidative stress.

3.
Immunology ; 173(1): 152-171, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38829009

RESUMO

Overexpression of T-cell immunoglobulin and mucin-domain containing-3 (TIM-3) on T cells has been observed in smokers. However, whether and how galectin-9 (Gal-9)/TIM-3 signal between T-regulatory cells (Tregs) and type 17 helper (Th17) cells contributes to tobacco smoke-induced airway inflammation remains unclear. Here, we aimed to explore the role of the Gal-9/TIM-3 signal between Tregs and Th17 cells during chronic tobacco smoke exposure. Tregs phenotype and the expression of TIM-3 on CD4+ T cells were detected in a mouse model of experimental emphysema. The role of TIM-3 in CD4+ T cells was explored in a HAVCR2-/- mouse model and in mice that received recombinant anti-TIM3. The crosstalk between Gal-9 and Tim-3 was evaluated by coculture Tregs with effector CD4+ T cells. We also invested the expression of Gal-9 in Tregs in patients with COPD. Our study revealed that chronic tobacco smoke exposure significantly reduces the frequency of Tregs in the lungs of mice and remarkably shapes the heterogeneity of Tregs by downregulating the expression of Gal-9. We observed a pro-inflammatory but restrained phenotypic transition of CD4+ T cells after tobacco smoke exposure, which was maintained by TIM-3. The restrained phenotype of CD4+ T cells was perturbed when TIM-3 was deleted or neutralised. Tregs from the lungs of mice with emphysema displayed a blunt ability to inhibit the differentiation and proliferation of Th17 cells. The inhibitory function of Tregs was partially restored by using recombinant Gal-9. The interaction between Gal-9 and TIM-3 inhibits the differentiation of Th17 cells and promotes apoptosis of CD4+ T cells, possibly by interfering with the expression of retinoic acid receptor-related orphan receptor gamma t. The expression of Gal-9 in Tregs was reduced in patients with COPD, which was associated with Th17 response and lung function. These findings present a new paradigm that impairment of Gal-9/Tim-3 crosstalk between Tregs and Th17 cells during chronic tobacco smoke exposure promotes tobacco smoke-induced airway/lung inflammation.


Assuntos
Galectinas , Receptor Celular 2 do Vírus da Hepatite A , Doença Pulmonar Obstrutiva Crônica , Linfócitos T Reguladores , Células Th17 , Animais , Feminino , Humanos , Masculino , Camundongos , Modelos Animais de Doenças , Galectinas/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/metabolismo , Receptor Celular 2 do Vírus da Hepatite A/genética , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/metabolismo , Transdução de Sinais , Fumar/efeitos adversos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Células Th17/imunologia , Células Th17/metabolismo
4.
Int J Cancer ; 155(7): 1268-1277, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38924042

RESUMO

Several life-prolonging therapies for metastatic castration-resistant prostate cancer (mCRPC) are available, including radium-223 dichloride (223Ra), which was approved based on phase 3 data demonstrating improved overall survival (OS) and a favorable safety profile. To date, real-world evidence for 223Ra use in Taiwan is from three studies of <50 patients. This observational study (NCT04232761) enrolled male patients with histologically/cytologically confirmed mCRPC with bone metastases from centers across Taiwan. 223Ra was prescribed as part of routine practice by investigators. Patients with prior 223Ra treatment were excluded. The primary objective was to assess 223Ra safety; secondary objectives evaluated efficacy parameters, including OS. Overall, 224 patients were enrolled. Most patients had an Eastern Cooperative Oncology Group performance status of 0/1 (79.0%) and ≤20 bone metastases (69.2%); no patients had visceral metastases. 223Ra was first- or second-line therapy in 23.2% and 47.7% of patients, respectively. The total proportion of patients who received 5-6 223Ra cycles was 68.8%; this proportion was greater with first-line use (84.3%) than second- (65.7%) or third-/fourth-line use (64.1%). More chemotherapy-naïve patients (61.9%) completed the 6-cycle 223Ra treatment than chemotherapy-exposed patients (56.7%). Any-grade treatment-emergent adverse events (TEAEs) and serious TEAEs occurred in 54.0% and 28.6% of patients, respectively, while 12% experienced 223Ra-related adverse events. Median OS was 15.7 months (95% confidence interval 12.13-19.51); patients receiving 5-6 223Ra injections and earlier 223Ra use had longer OS than those receiving fewer injections and later 223Ra use. 223Ra provides a well-tolerated and effective treatment for Taiwanese patients with mCRPC and bone metastases.


Assuntos
Neoplasias Ósseas , Neoplasias de Próstata Resistentes à Castração , Rádio (Elemento) , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/radioterapia , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/mortalidade , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Rádio (Elemento)/uso terapêutico , Rádio (Elemento)/efeitos adversos , Idoso , Neoplasias Ósseas/secundário , Neoplasias Ósseas/radioterapia , Estudos Prospectivos , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Taiwan/epidemiologia , Resultado do Tratamento , Radioisótopos/uso terapêutico , Radioisótopos/efeitos adversos
5.
Microb Pathog ; 191: 106660, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38657710

RESUMO

Endometritis is the inflammation of the endothelial lining of the uterine lumen and is multifactorial in etiology. Escherichia (E.) coli is a Gram-negative bacteria, generally considered as a primary causative agent for bovine endometritis. Bovine endometritis is characterized by the activation of Toll-like receptors (TLRs) by E. coli, which in turn triggers inflammation, oxidative stress, and apoptosis. The objective of this study was to investigate the gene expression of inflammatory, oxidative stress, and apoptotic markers related to endometritis in the uteri of cows. Twenty uterine tissues were collected from the abattoir. Histologically, congestion, edema, hyperemia, and hemorrhagic lesions with massive infiltration of neutrophil and cell necrosis were detected markedly (P < 0.05) in infected uterine samples. Additionally, we identify E. coli using the ybbW gene (177 base pairs; E. coli-specific gene) from infected uterine samples. Moreover, qPCR and western blot results indicated that TLR2, TLR4, proinflammatory mediators, and apoptosis-mediated genes upregulated except Bcl-2, which is antiapoptotic, and there were downregulations of oxidative stress-related genes in the infected uterine tissue. The results of our study suggested that different gene expression regimes related to the immune system reflex were activated in infected uteri. This research gives a novel understanding of active immunological response in bovine endometritis.


Assuntos
Apoptose , Doenças dos Bovinos , Endometrite , Infecções por Escherichia coli , Escherichia coli , Estresse Oxidativo , Regulação para Cima , Útero , Bovinos , Animais , Feminino , Endometrite/veterinária , Endometrite/microbiologia , Endometrite/patologia , Endometrite/metabolismo , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/imunologia , Escherichia coli/genética , Escherichia coli/patogenicidade , Infecções por Escherichia coli/veterinária , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/imunologia , Infecções por Escherichia coli/patologia , Útero/patologia , Útero/microbiologia , Útero/metabolismo , Inflamação , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Mediadores da Inflamação/metabolismo , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
6.
Opt Lett ; 49(9): 2449-2452, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691741

RESUMO

Broadband frequency comb generation through cascaded quadratic nonlinearity remains experimentally untapped in free-space cavities with bulk χ(2) materials mainly due to the high threshold power and restricted ability of dispersion engineering. Thin-film lithium niobate (LN) is a good platform for nonlinear optics due to the tight mode confinement in a nano-dimensional waveguide, the ease of dispersion engineering, large quadratic nonlinearities, and flexible phase matching via periodic poling. Here we demonstrate broadband frequency comb generation through dispersion engineering in a thin-film LN microresonator. Bandwidths of 150 nm (80 nm) and 25 nm (12 nm) for center wavelengths at 1560 and 780 nm are achieved, respectively, in a cavity-enhanced second-harmonic generation (doubly resonant optical parametric oscillator). Our demonstration paves the way for pure quadratic soliton generation, which is a great complement to dissipative Kerr soliton frequency combs for extended interesting nonlinear applications.

7.
Mol Cell Biochem ; 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38347264

RESUMO

Cancer immunotherapies have greatly changed the prospects for the therapy of many malignancies, including colon cancer. Macrophages as the effectors of cancer immunotherapy provide considerable promise for cancer treatment. Prolyl 4-hydroxylase subunit alpha 3 (P4HA3) plays a cancer-promoting role in a variety of cancers, including colon cancer. In the present work, we provided evidence for the first time that P4HA3 promoted colon cancer cell escape from macrophage phagocytosis, and preliminarily explored its possible molecular mechanism. Immunohistochemistry was used to detect the expression of P4HA3 in tissues. Bioinformatics methods were used to analyze the tumor public databases (including TCGA database and GEO database). Macrophage phagocytosis assay and flow cytometric analysis were used to detect the phagocytic capacity of macrophages. Western blot and qRT-PCR were used to detect the expression of related markers (such as P4HA3, CD47, CD24, IL-34, and M-CSF). First, we found that P4HA3 was significantly and highly expressed in both colon cancer tissues and cells, and that P4HA3 had a positive correlation with lymph node metastasis, Dukes stage and also strongly correlated with poorer survival. Subsequently, we found that P4HA3 was strongly associated with the macrophage infiltration level in colon cancer. Immediately we also found that decreasing P4HA3 expression promoted macrophage phagocytosis in colon cancer cells, whereas P4HA3 overexpression produced the opposite effect. Finally, we demonstrated that P4HA3 promoted the expression of cluster of differentiation 47 (CD47) in colon cancer cells. Moreover, P4HA3 caused colon cancer cells to secrete Interleukin 34 (IL34) and Macrophage colony stimulating factor (M-CSF), which further induced macrophages to differentiate to M2 type and thereby contributed to the progression of colon cancer. We have demonstrated that P4HA3-driven CD47 overexpression may act as an escape mechanism, causing colon cancer cells to evade phagocytosis from macrophages.

8.
Microb Cell Fact ; 23(1): 190, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956607

RESUMO

BACKGROUND: Carbonic anhydrase (CA) enzymes facilitate the reversible hydration of CO2 to bicarbonate ions and protons. Identifying efficient and robust CAs and expressing them in model host cells, such as Escherichia coli, enables more efficient engineering of these enzymes for industrial CO2 capture. However, expression of CAs in E. coli is challenging due to the possible formation of insoluble protein aggregates, or inclusion bodies. This makes the production of soluble and active CA protein a prerequisite for downstream applications. RESULTS: In this study, we streamlined the process of CA expression by selecting seven top CA candidates and used two bioinformatic tools to predict their solubility for expression in E. coli. The prediction results place these enzymes in two categories: low and high solubility. Our expression of high solubility score CAs (namely CA5-SspCA, CA6-SazCAtrunc, CA7-PabCA and CA8-PhoCA) led to significantly higher protein yields (5 to 75 mg purified protein per liter) in flask cultures, indicating a strong correlation between the solubility prediction score and protein expression yields. Furthermore, phylogenetic tree analysis demonstrated CA class-specific clustering patterns for protein solubility and production yields. Unexpectedly, we also found that the unique N-terminal, 11-amino acid segment found after the signal sequence (not present in its homologs), was essential for CA6-SazCA activity. CONCLUSIONS: Overall, this work demonstrated that protein solubility prediction, phylogenetic tree analysis, and experimental validation are potent tools for identifying top CA candidates and then producing soluble, active forms of these enzymes in E. coli. The comprehensive approaches we report here should be extendable to the expression of other heterogeneous proteins in E. coli.


Assuntos
Anidrases Carbônicas , Biologia Computacional , Escherichia coli , Solubilidade , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/enzimologia , Anidrases Carbônicas/metabolismo , Anidrases Carbônicas/genética , Biologia Computacional/métodos , Filogenia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Dióxido de Carbono/metabolismo
9.
Fish Shellfish Immunol ; 153: 109842, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39153580

RESUMO

Molting is a crucial biological process of crustaceans. Crustaceans go through three separate stages throughout their molting process, including pre-molt, post-molt and inter-molt. However, the exact mechanism of immunological modulation during molting remains unclear. Tumor necrosis factor receptor-associated factor 6 (TRAF6) has been extensively documented to participate in immune defense. In the present study, a TRAF6 gene with two TRAF-type zinc finger domains was identified from Eriocheir sinensis (designed as EsTRAF6), and its role in regulating immune response during molting process was explored. The mRNA expression level of EsTRAF6 at pre-molt stage was higher than that at post-molt stage and inter-molt stage. After Aeromonas hydrophila stimulation, the expression levels of EsTRAF6, EsRelish and anti-lipopolysaccharide factors (ALFs) genes exhibited a considerable increase at three molting stages. Subsequently, the expression patterns of EsTRAF6 and EsRelish in response to the treatment with 20-hydroxyecdysone (20E) were examined. The mRNA expression of EsTRAF6 and EsRelish were significantly increased at 12 h after 20E injection. Additionally, the protein expression level of TRAF6 was also up-regulated in 20E group compared to control group. Furthermore, the role of EsTRAF6 in regulating the anti- ALFs expression at pre-molt stage post A. hydrophila stimulation was investigated. Following the inhibition of the EsTRAF6 transcript using RNAi or the injection of inhibitor (TMBPS), there was a notable decrease of the EsALF1, EsALF2 and EsALF3 transcripts. Moreover, a significant reduction in the phosphorylation level of NF-κB at pre-molt stage was observed after A. hydrophila stimulation in TRAF6-inhibited crabs. Collectively, our results suggest that EsTRAF6 could be induced by 20E and promoted the EsALFs expression by activating NF-κB at pre-molt stage, which provides a novel insight into the research of immune regulatory mechanism during the process of molting of crustaceans.

10.
Inorg Chem ; 63(29): 13594-13601, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-38973091

RESUMO

The development of low-cost and efficient photocatalysts to achieve water splitting to hydrogen (H2) is highly desirable but remains challenging. Herein, we design and synthesize two porous polymers (Co-Salen-P and Fe-Salen-P) by covalent bonding of salen metal complexes and pyrene chromophores for photocatalytic H2 evolution. The catalytic results demonstrate that the two polymers exhibit excellent catalytic performance for H2 generation in the absence of additional noble-metal photosensitizers and cocatalysts. Particularly, the H2 generation rate of Co-Salen-P reaches as high as 542.5 µmol g-1 h-1, which is not only 6 times higher than that of Fe-Salen-P but also higher than a large amount of reported Pt-assisted photocatalytic systems. Systematic studies show that Co-Salen-P displays faster charge separation and transfer efficiencies, thereby accounting for the significantly improved photocatalytic activity. This study provides a facile and efficient way to fabricate high-performance photocatalysts for H2 production.

11.
BMC Gastroenterol ; 24(1): 99, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443794

RESUMO

In this study, we implemented a combination of data augmentation and artificial intelligence (AI) model-Convolutional Neural Network (CNN)-to help physicians classify colonic polyps into traditional adenoma (TA), sessile serrated adenoma (SSA), and hyperplastic polyp (HP). We collected ordinary endoscopy images under both white and NBI lights. Under white light, we collected 257 images of HP, 423 images of SSA, and 60 images of TA. Under NBI light, were collected 238 images of HP, 284 images of SSA, and 71 images of TA. We implemented the CNN-based artificial intelligence model, Inception V4, to build a classification model for the types of colon polyps. Our final AI classification model with data augmentation process is constructed only with white light images. Our classification prediction accuracy of colon polyp type is 94%, and the discriminability of the model (area under the curve) was 98%. Thus, we can conclude that our model can help physicians distinguish between TA, SSA, and HPs and correctly identify precancerous lesions such as TA and SSA.


Assuntos
Adenoma , Pólipos , Humanos , Inteligência Artificial , Endoscopia , Redes Neurais de Computação , Adenoma/diagnóstico por imagem
12.
Circ J ; 88(5): 663-671, 2024 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-38325819

RESUMO

BACKGROUND: Complications arising from transcatheter closure of perimembranous ventricular septal defects (pmVSD) in children, such as residual shunts and aortic regurgitation (AR), have been observed. However, the associated risk factors remain unclear. This study identified risk factors linked with residual shunts and AR following transcatheter closure of pmVSD in children aged 2-12 years. METHODS AND RESULTS: The medical records of 63 children with pmVSD and a pulmonary-to-systemic blood flow ratio <2.0 who underwent transcatheter closure between 2011 and 2018 were analyzed with a minimum 3-year follow-up. The success rate of transcatheter closure was 98.4%, with no emergency surgery, permanent high-degree atrioventricular block, or mortality. Defects ≥4.5 mm had significantly higher odds of persistent residual shunt (odds ratio [OR] 6.85; P=0.03). The use of an oversize device (≥1.5 mm) showed a trend towards reducing residual shunts (OR 0.23; P=0.06). Age <4 years (OR 27.38; 95% confidence interval [CI] 2.33-321.68) and perimembranous outlet-type VSD (OR 11.94, 95% CI 1.10-129.81) were independent risk factors for AR progression after closure. CONCLUSIONS: Careful attention is crucial for pmVSDs ≥4.5 mm to prevent persistent residual shunts in transcatheter closure. Assessing AR risk, particularly in children aged <4 years, is essential while considering the benefits of pmVSD closure.


Assuntos
Cateterismo Cardíaco , Comunicação Interventricular , Humanos , Comunicação Interventricular/cirurgia , Pré-Escolar , Criança , Fatores de Risco , Masculino , Feminino , Cateterismo Cardíaco/efeitos adversos , Estudos Retrospectivos , Dispositivo para Oclusão Septal/efeitos adversos , Resultado do Tratamento , Insuficiência da Valva Aórtica/etiologia , Fatores Etários , Fatores de Tempo , Seguimentos , Complicações Pós-Operatórias/etiologia
13.
Artigo em Inglês | MEDLINE | ID: mdl-39191223

RESUMO

INTRODUCTION: Disparities in physical fitness between immediately before dialysis (pre-D) and the day following dialysis (non-D) have not been investigated despite potential adverse factors such as fluid status, uremia, and electrolyte levels in the predialysis period. The effect of acute exercise immediately before hemodialysis (HD) on HD-related hypotension remains unclear. We hypothesized that cardiopulmonary performance and muscular strength would be inferior in the immediate pre-D period compared to those non-D. METHODS: Twenty patients receiving chronic HD treatments underwent symptom-limited incremental cardiopulmonary exercise testing (CPET) and isokinetic testing both 1-2 h prior to dialysis (pre-D) and non-D. This investigation was a sub-study of a clinical trial assessing the efficacy of a pre-D exercise training program. Blood pressure profiles during HD post-CPET and pre-D exercise training were compared with those during usual HD sessions. RESULTS: No adverse events were observed during the 80 exercise tests. Prior to dialysis, the nadir of the ventilatory equivalent of CO2 was slightly elevated, the resting heart rate was lower, and the peak systolic blood pressure was higher than those non-D. Contrary to our hypothesis, peak V̇O2 and quadriceps peak torque showed no differences. Blood pressure profiles during HD post-exercise were similar to those during sessions without prior exercise, except for a lower resting systolic blood pressure at the beginning of HD. CONCLUSION: Cardiopulmonary response and muscular strength in the 1-2 h prior to HD were comparable with those on the day following HD, with only minor clinically insignificant differences. Acute exercise prior to HD did not affect the magnitude of hypotension during HD. This study suggests a potential alternative timing for exercise training or testing in patients undergoing chronic HD.

14.
Nature ; 558(7710): 410-414, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29892031

RESUMO

Optical frequency combs, which emit pulses of light at discrete, equally spaced frequencies, are cornerstones of modern-day frequency metrology, precision spectroscopy, astronomical observations, ultrafast optics and quantum information1-7. Chip-scale frequency combs, based on the Kerr and Raman nonlinearities in monolithic microresonators with ultrahigh quality factors8-10, have recently led to progress in optical clockwork and observations of temporal cavity solitons11-14. But the chromatic dispersion within a laser cavity, which determines the comb formation15,16, is usually difficult to tune with an electric field, whether in microcavities or fibre cavities. Such electrically dynamic control could bridge optical frequency combs and optoelectronics, enabling diverse comb outputs in one resonator with fast and convenient tunability. Arising from its exceptional Fermi-Dirac tunability and ultrafast carrier mobility17-19, graphene has a complex optical dispersion determined by its optical conductivity, which can be tuned through a gate voltage20,21. This has brought about optoelectronic advances such as modulators22,23, photodetectors 24 and controllable plasmonics25,26. Here we demonstrate the gated intracavity tunability of graphene-based optical frequency combs, by coupling the gate-tunable optical conductivity to a silicon nitride photonic microresonator, thus modulating its second- and higher-order chromatic dispersions by altering the Fermi level. Preserving cavity quality factors up to 106 in the graphene-based comb, we implement a dual-layer ion-gel-gated transistor to tune the Fermi level of graphene across the range 0.45-0.65 electronvolts, under single-volt-level control. We use this to produce charge-tunable primary comb lines from 2.3 terahertz to 7.2 terahertz, coherent Kerr frequency combs, controllable Cherenkov radiation and controllable soliton states, all in a single microcavity. We further demonstrate voltage-tunable transitions from periodic soliton crystals to crystals with defects, mapped by our ultrafast second-harmonic optical autocorrelation. This heterogeneous graphene microcavity, which combines single-atomic-layer nanoscience and ultrafast optoelectronics, will help to improve our understanding of dynamical frequency combs and ultrafast optics.

15.
Acta Pharmacol Sin ; 45(7): 1438-1450, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38565961

RESUMO

Angiogenesis plays a critical role in many pathological processes, including irreversible blindness in eye diseases such as retinopathy of prematurity. Endothelial mitochondria are dynamic organelles that undergo constant fusion and fission and are critical signalling hubs that modulate angiogenesis by coordinating reactive oxygen species (ROS) production and calcium signalling and metabolism. In this study, we investigated the role of mitochondrial dynamics in pathological retinal angiogenesis. We showed that treatment with vascular endothelial growth factor (VEGF; 20 ng/ml) induced mitochondrial fission in HUVECs by promoting the phosphorylation of dynamin-related protein 1 (DRP1). DRP1 knockdown or pretreatment with the DRP1 inhibitor Mdivi-1 (5 µM) blocked VEGF-induced cell migration, proliferation, and tube formation in HUVECs. We demonstrated that VEGF treatment increased mitochondrial ROS production in HUVECs, which was necessary for HIF-1α-dependent glycolysis, as well as proliferation, migration, and tube formation, and the inhibition of mitochondrial fission prevented VEGF-induced mitochondrial ROS production. In an oxygen-induced retinopathy (OIR) mouse model, we found that active DRP1 was highly expressed in endothelial cells in neovascular tufts. The administration of Mdivi-1 (10 mg·kg-1·d-1, i.p.) for three days from postnatal day (P) 13 until P15 significantly alleviated pathological angiogenesis in the retina. Our results suggest that targeting mitochondrial fission may be a therapeutic strategy for proliferative retinopathies and other diseases that are dependent on pathological angiogenesis.


Assuntos
Movimento Celular , Dinaminas , Células Endoteliais da Veia Umbilical Humana , Subunidade alfa do Fator 1 Induzível por Hipóxia , Camundongos Endogâmicos C57BL , Dinâmica Mitocondrial , Quinazolinonas , Espécies Reativas de Oxigênio , Neovascularização Retiniana , Fator A de Crescimento do Endotélio Vascular , Dinâmica Mitocondrial/efeitos dos fármacos , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Humanos , Espécies Reativas de Oxigênio/metabolismo , Dinaminas/metabolismo , Dinaminas/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo , Quinazolinonas/farmacologia , Neovascularização Retiniana/metabolismo , Neovascularização Retiniana/patologia , Neovascularização Retiniana/tratamento farmacológico , Movimento Celular/efeitos dos fármacos , Camundongos , Proliferação de Células/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Angiogênese
16.
Acta Pharmacol Sin ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982150

RESUMO

Olfactory dysfunction is increasingly recognized as an early indicator of Alzheimer's disease (AD). Aberrations in GABAergic function and the excitatory/inhibitory (E/I) balance within the olfactory bulb (OB) have been implicated in olfactory impairment during the initial stages of AD. While the neuregulin 1 (NRG1)/ErbB4 signaling pathway is known to regulate GABAergic transmission in the brain and is associated with various neuropsychiatric disorders, its specific role in early AD-related olfactory impairment remains incompletely understood. This study demonstrated that olfactory dysfunction preceded cognitive decline in young adult APP/PS1 mice and was characterized by reduced levels of NRG1 and ErbB4 in the OB. Further investigation revealed that deletion of ErbB4 in parvalbumin interneurons reduced GABAergic transmission and increased hyperexcitability in mitral and tufted cells (M/Ts) in the OB, thereby accelerating olfactory dysfunction in young adult APP/PS1 mice. Additionally, ErbB4 deficiency was associated with increased accumulation of Aß and BACE1-mediated cleavage of APP, along with enhanced CDK5 signaling in the OB. NRG1 infusion into the OB was found to enhance GABAergic transmission in M/Ts and alleviate olfactory dysfunction in young adult APP/PS1 mice. These findings underscore the critical role of NRG1/ErbB4 signaling in regulating GABAergic transmission and E/I balance within the OB, contributing to olfactory impairment in young adult APP/PS1 mice, and provide novel insights for early intervention strategies in AD. This work has shown that ErbB4 deficiency increased the burden of Aß, impaired GABAergic transmission, and disrupted the E/I balance of mitral and tufted cells (M/Ts) in the OB, ultimately resulting in olfactory dysfunction in young adult APP/PS1 mice. NRG1 could enhance GABAergic transmission, rescue E/I imbalance in M/Ts, and alleviate olfactory dysfunction in young adult APP/PS1 mice. OB: olfactory bulb, E/I: excitation/inhibition, Pr: probability of release, PV: parvalbumin interneurons, Aß: ß-amyloid, GABA: gamma-aminobutyric acid.

17.
Dig Dis Sci ; 69(6): 2235-2246, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38602621

RESUMO

BACKGROUND: Acute pancreatitis is easily confused with abdominal pain symptoms, and it could lead to serious complications for pregnant women and fetus, the mortality was as high as 3.3% and 11.6-18.7%, respectively. However, there is still lack of sensitive laboratory markers for early diagnosis of APIP and authoritative guidelines to guide treatment. OBJECTIVE: The purpose of this study was to explore the risk factors of acute pancreatitis in pregnancy, establish, and evaluate the dynamic prediction model of risk factors in acute pancreatitis in pregnancy patients. STUDY DESIGN: Clinical data of APIP patients and non-pregnant acute pancreases patients who underwent regular antenatal check-ups during the same period were collected. The dataset after propensity matching was randomly divided into training set and verification set at a ratio of 7:3. The model was constructed using Logistic regression, least absolute shrinkage and selection operator regression, R language and other methods. The training set model was used to construct the diagnostic nomogram model and the validation set was used to validate the model. Finally, the accuracy and clinical practicability of the model were evaluated. RESULTS: A total of 111 APIP were included. In all APIP patients, hyperlipidemic pancreatitis was the most important reason. The levels of serum amylase, creatinine, albumin, triglyceride, high-density lipoprotein cholesterol, and apolipoprotein A1 were significantly different between the two groups. The propensity matching method was used to match pregnant pancreatitis patients and pregnant non-pancreatic patients 1:1 according to age and gestational age, and the matching tolerance was 0.02. The multivariate logistic regression analysis of training set showed that diabetes, triglyceride, Body Mass Index, white blood cell, and C-reactive protein were identified and entered the dynamic nomogram. The area under the ROC curve of the training set was 0.942 and in validation set was 0.842. The calibration curve showed good predictive in training set, and the calibration performance in the validation set was acceptable. The calibration curve showed the consistency between the nomogram model and the actual probability. CONCLUSION: The dynamic nomogram model we constructed to predict the risk factors of acute pancreatitis in pregnancy has high accuracy, discrimination, and clinical practicability.


Assuntos
Nomogramas , Pancreatite , Complicações na Gravidez , Pontuação de Propensão , Humanos , Feminino , Gravidez , Pancreatite/diagnóstico , Pancreatite/sangue , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/sangue , Complicações na Gravidez/epidemiologia , Medição de Risco/métodos , Adulto , Fatores de Risco , Doença Aguda , Estudos Retrospectivos
18.
Int J Med Sci ; 21(10): 1799-1805, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39113890

RESUMO

Background: Current treatments with urate-lowering therapy (ULT) are effective for most patients with gout. However, approximately 10% of these patients do not respond well to ULT and develop chronic tophus lesions. Objective: This study aimed to evaluate the efficacy of surgery involving the shaver technique against chronic tophus lesions. Methods: This single-center, retrospective cohort study included 217 patients who had cumulatively undergone 303 shaver-assisted procedures between 2002 and 2018. Surgical outcomes were assessed in terms of the length of hospital stay (LOS) and wound healing time. Results: LOS and wound healing time were longer in patients with a preoperative tophus infection and lower extremity lesions than in those without infection and with upper extremity lesions (respectively, LOS: 12.7 vs. 8.6 days; wound healing time: 22.7 vs. 16.3 days). However, factors such as age, sex, body mass index, renal function, or uricemia level exerted no significant effect on surgical outcomes. Conclusion: Surgery involving the shaver technique should be performed before tophus infection. Clinical outcomes tend to be better for upper extremity lesions than for lower extremity lesions.


Assuntos
Gota , Tempo de Internação , Cicatrização , Humanos , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Cicatrização/efeitos dos fármacos , Gota/cirurgia , Tempo de Internação/estatística & dados numéricos , Doença Crônica , Adulto , Extremidade Superior/cirurgia , Idoso de 80 Anos ou mais , Extremidade Inferior/cirurgia
19.
Biosci Biotechnol Biochem ; 88(5): 529-537, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38509025

RESUMO

Four ethanol fractionated crude extracts (EFCEs [A-D]) purified from the leaves of Cinnamomum macrostemon Hayata were screened for antioxidative effects and mitochondrial function in HaCaT cells. The higher cell viability indicated that EFCE C was mildly toxic. Under the treatment of 50 ng/mL EFCE C, the hydrogen peroxide (H2O2)-induced cytosolic and mitochondrial reactive oxygen species levels were reduced as well as the H2O2-impaired cell viability, mitochondrial membrane potential (MMP), ATP production, and mitochondrial mass. The conversion of globular mitochondria to tubular mitochondria is coincident with EFCE C-restored mitochondrial function. The mitophagy activator rapamycin showed similar effects to EFCE C in recovering the H2O2-impaired cell viability, MMP, ATP production, mitochondrial mass, and also mitophagic proteins such as PINK1, Parkin, LC3 II, and biogenesis protein PGC-1α. We thereby propose the application of EFCE C in the prevention of oxidative stress in skin cells.


Assuntos
Sobrevivência Celular , Cinnamomum , Peróxido de Hidrogênio , Queratinócitos , Potencial da Membrana Mitocondrial , Mitocôndrias , Mitofagia , Estresse Oxidativo , Extratos Vegetais , Espécies Reativas de Oxigênio , Humanos , Mitofagia/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/citologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Peróxido de Hidrogênio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Cinnamomum/química , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Trifosfato de Adenosina/metabolismo , Folhas de Planta/química , Antioxidantes/farmacologia , Ubiquitina-Proteína Ligases/metabolismo , Sirolimo/farmacologia , Células HaCaT , Proteínas Quinases/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética
20.
Artigo em Inglês | MEDLINE | ID: mdl-39115820

RESUMO

OBJECTIVES: Airway anomalies increase risk of morbidity and mortality in postoperative pediatric patients with congenital heart disease (CHD). We aimed to identify airway anomalies and the association with intermediate outcomes in patients undergoing surgery for CHD. DESIGN: Single-center, hospital-based retrospective study in Taiwan, 2017-2020. SETTING: A tertiary referral hospital in Taiwan. PATIENTS: All pediatric patients who underwent surgery for CHD and were admitted to the PICU and had data about airway evaluation by cardiopulmonary CT scan or bronchoscopy. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 820 CHD patients identified as having undergone airway evaluation in the PICU, 185 (22.6%) were diagnosed with airway anomalies, including structural lesions in 146 of 185 (78.9%), and dynamic problems were seen in 87 of 185 (47.0%). In this population, the explanatory factors associated with greater odds (odds ratio [OR]) of airway anomaly were premature birth (OR, 1.90; p = 0.002), genetic syndromes (OR, 2.60; p < 0.001), and in those with preoperative ventilator use (OR, 4.28; p < 0.001). In comparison to those without airway anomalies, the presence of airway anomalies was associated with higher hospital mortality (11.4% vs. 2.7%; p < 0.001), prolonged intubation days (8 d [1-27 d] vs. 1 d [1-5 d]; p < 0.001), longer PICU length of stay (23 d [8-81 d] vs. 7 d [4-18 d]; p < 0.001), and greater hazard of intermediate mortality (adjusted hazard ratio, 2.60; p = 0.001). CONCLUSIONS: In our single-center retrospective study, 2017-2020, between one-in-five and one-in-four of our postoperative CHD patients undergoing an airway evaluation had airway anomalies. Factors associated with greater odds of airway anomaly included, those with premature birth, or genetic syndromes, and preoperative ventilator use. Overall, in patients undergoing airway evaluation, the finding of an airway anomalies was associated with longer postoperative intubation duration and greater hazard of intermediate mortality.

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