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1.
Nano Lett ; 24(30): 9163-9168, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39037721

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-37660919

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38829009

RESUMEN

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.


Asunto(s)
Galectinas , Receptor 2 Celular del Virus de la Hepatitis A , Enfermedad Pulmonar Obstructiva Crónica , Linfocitos T Reguladores , Células Th17 , Animales , Femenino , Humanos , Masculino , Ratones , Modelos Animales de Enfermedad , Galectinas/metabolismo , Receptor 2 Celular del Virus de la Hepatitis A/metabolismo , Receptor 2 Celular del Virus de la Hepatitis A/genética , Pulmón/inmunología , Pulmón/metabolismo , Pulmón/patología , Ratones Endogámicos C57BL , Ratones Noqueados , Enfermedad Pulmonar Obstructiva Crónica/inmunología , Enfermedad Pulmonar Obstructiva Crónica/metabolismo , Transducción de Señal , Fumar/efectos adversos , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células Th17/inmunología , Células Th17/metabolismo
4.
Int J Cancer ; 155(7): 1268-1277, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38924042

RESUMEN

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.


Asunto(s)
Neoplasias Óseas , Neoplasias de la Próstata Resistentes a la Castración , Radio (Elemento) , Humanos , Masculino , Neoplasias de la Próstata Resistentes a la Castración/radioterapia , Neoplasias de la Próstata Resistentes a la Castración/patología , Neoplasias de la Próstata Resistentes a la Castración/mortalidad , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Radio (Elemento)/uso terapéutico , Radio (Elemento)/efectos adversos , Anciano , Neoplasias Óseas/secundario , Neoplasias Óseas/radioterapia , Estudios Prospectivos , Persona de Mediana Edad , Anciano de 80 o más Años , Taiwán/epidemiología , Resultado del Tratamiento , Radioisótopos/uso terapéutico , Radioisótopos/efectos adversos
5.
Microb Pathog ; 191: 106660, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38657710

RESUMEN

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.


Asunto(s)
Apoptosis , Enfermedades de los Bovinos , Endometritis , Infecciones por Escherichia coli , Escherichia coli , Estrés Oxidativo , Regulación hacia Arriba , Útero , Bovinos , Animales , Femenino , Endometritis/veterinaria , Endometritis/microbiología , Endometritis/patología , Endometritis/metabolismo , Enfermedades de los Bovinos/microbiología , Enfermedades de los Bovinos/metabolismo , Enfermedades de los Bovinos/inmunología , Escherichia coli/genética , Escherichia coli/patogenicidad , Infecciones por Escherichia coli/veterinaria , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/inmunología , Infecciones por Escherichia coli/patología , Útero/patología , Útero/microbiología , Útero/metabolismo , Inflamación , Receptor Toll-Like 4/genética , Receptor Toll-Like 4/metabolismo , Mediadores de Inflamación/metabolismo , Receptor Toll-Like 2/genética , Receptor Toll-Like 2/metabolismo , Receptores Toll-Like/genética , Receptores Toll-Like/metabolismo
6.
Opt Lett ; 49(9): 2449-2452, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38691741

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38347264

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38956607

RESUMEN

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.


Asunto(s)
Anhidrasas Carbónicas , Biología Computacional , Escherichia coli , Solubilidad , Escherichia coli/genética , Escherichia coli/metabolismo , Escherichia coli/enzimología , Anhidrasas Carbónicas/metabolismo , Anhidrasas Carbónicas/genética , Biología Computacional/métodos , Filogenia , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Dióxido de Carbono/metabolismo
9.
Fish Shellfish Immunol ; 153: 109842, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39153580

RESUMEN

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.


Asunto(s)
Proteínas de Artrópodos , Decápodos , FN-kappa B , Factor 6 Asociado a Receptor de TNF , Animales , Aeromonas hydrophila/fisiología , Secuencia de Aminoácidos , Proteínas de Artrópodos/genética , Proteínas de Artrópodos/inmunología , Proteínas de Artrópodos/química , Perfilación de la Expresión Génica/veterinaria , Regulación de la Expresión Génica/inmunología , Inmunidad Innata/genética , Muda/inmunología , Muda/genética , FN-kappa B/genética , FN-kappa B/metabolismo , FN-kappa B/inmunología , Filogenia , Alineación de Secuencia/veterinaria , Factor 6 Asociado a Receptor de TNF/genética , Factor 6 Asociado a Receptor de TNF/inmunología
10.
Inorg Chem ; 63(29): 13594-13601, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-38973091

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38443794

RESUMEN

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.


Asunto(s)
Adenoma , Pólipos , Humanos , Inteligencia Artificial , Endoscopía , Redes Neurales de la Computación , Adenoma/diagnóstico por imagen
12.
Circ J ; 88(5): 663-671, 2024 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-38325819

RESUMEN

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.


Asunto(s)
Cateterismo Cardíaco , Defectos del Tabique Interventricular , Humanos , Defectos del Tabique Interventricular/cirugía , Preescolar , Niño , Factores de Riesgo , Masculino , Femenino , Cateterismo Cardíaco/efectos adversos , Estudios Retrospectivos , Dispositivo Oclusor Septal/efectos adversos , Resultado del Tratamiento , Insuficiencia de la Válvula Aórtica/etiología , Factores de Edad , Factores de Tiempo , Estudios de Seguimiento , Complicaciones Posoperatorias/etiología
13.
Kidney Blood Press Res ; 49(1): 735-744, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39191223

RESUMEN

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 pre-dialysis 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 V˙O2 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.


Asunto(s)
Prueba de Esfuerzo , Ejercicio Físico , Diálisis Renal , Humanos , Diálisis Renal/efectos adversos , Proyectos Piloto , Masculino , Femenino , Persona de Mediana Edad , Ejercicio Físico/fisiología , Anciano , Presión Sanguínea , Fuerza Muscular , Frecuencia Cardíaca
14.
Nature ; 558(7710): 410-414, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29892031

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38565961

RESUMEN

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.


Asunto(s)
Movimiento Celular , Dinaminas , Células Endoteliales de la Vena Umbilical Humana , Subunidad alfa del Factor 1 Inducible por Hipoxia , Ratones Endogámicos C57BL , Dinámicas Mitocondriales , Quinazolinonas , Especies Reactivas de Oxígeno , Neovascularización Retiniana , Factor A de Crecimiento Endotelial Vascular , Dinámicas Mitocondriales/efectos de los fármacos , Animales , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Humanos , Especies Reactivas de Oxígeno/metabolismo , Dinaminas/metabolismo , Dinaminas/antagonistas & inhibidores , Factor A de Crecimiento Endotelial Vascular/metabolismo , Quinazolinonas/farmacología , Neovascularización Retiniana/metabolismo , Neovascularización Retiniana/patología , Neovascularización Retiniana/tratamiento farmacológico , Movimiento Celular/efectos de los fármacos , Ratones , Proliferación Celular/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Angiogénesis
16.
Acta Pharmacol Sin ; 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38982150

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-38602621

RESUMEN

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.


Asunto(s)
Nomogramas , Pancreatitis , Complicaciones del Embarazo , Puntaje de Propensión , Humanos , Femenino , Embarazo , Pancreatitis/diagnóstico , Pancreatitis/sangre , Complicaciones del Embarazo/diagnóstico , Complicaciones del Embarazo/sangre , Complicaciones del Embarazo/epidemiología , Medición de Riesgo/métodos , Adulto , Factores de Riesgo , Enfermedad Aguda , Estudios Retrospectivos
18.
Int J Med Sci ; 21(10): 1799-1805, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39113890

RESUMEN

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.


Asunto(s)
Gota , Tiempo de Internación , Cicatrización de Heridas , Humanos , Masculino , Femenino , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , Resultado del Tratamiento , Cicatrización de Heridas/efectos de los fármacos , Gota/cirugía , Tiempo de Internación/estadística & datos numéricos , Enfermedad Crónica , Adulto , Extremidad Superior/cirugía , Anciano de 80 o más Años , Extremidad Inferior/cirugía
19.
J Nanobiotechnology ; 22(1): 555, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261846

RESUMEN

BACKGROUND: The pathogenesis of osteoarthritis (OA) involves the progressive degradation of articular cartilage. Exosomes derived from mesenchymal stem cells (MSC-EXOs) have been shown to mitigate joint pathological injury by attenuating cartilage destruction. Optimization the yield and therapeutic efficacy of exosomes derived from MSCs is crucial for promoting their clinical translation. The preconditioning of MSCs enhances the therapeutic potential of engineered exosomes, offering promising prospects for application by enabling controlled and quantifiable external stimulation. This study aims to address these issues by employing pro-inflammatory preconditioning of MSCs to enhance exosome production and augment their therapeutic efficacy for OA. METHODS: The exosomes were isolated from the supernatant of infrapatellar fat pad (IPFP)-MSCs preconditioned with a pro-inflammatory factor, TNF-α, and their production was subsequently quantified. The exosome secretion-related pathways in IPFP-MSCs were evaluated through high-throughput transcriptome sequencing analysis, q-PCR and western blot analysis before and after TNF-α preconditioning. Furthermore, exosomes derived from TNF-α preconditioned IPFP-MSCs (IPFP-MSC-EXOsTNF-α) were administered intra-articularly in an OA mouse model, and subsequent evaluations were conducted to assess joint pathology and gait alterations. The expression of proteins involved in the maintenance of cartilage homeostasis within the exosomes was determined through proteomic analysis. RESULTS: The preconditioning with TNF-α significantly enhanced the exosome secretion of IPFP-MSCs compared to unpreconditioned MSCs. The potential mechanism involved the activation of the PI3K/AKT signaling pathway in IPFP-MSCs by TNF-α precondition, leading to an up-regulation of autophagy-related protein 16 like 1(ATG16L1) levels, which subsequently facilitated exosome secretion. The intra-articular administration of IPFP-MSC-EXOsTNF-α demonstrated superior efficacy in ameliorating pathological changes in the joints of OA mice. The preconditioning of TNF-α enhanced the up-regulation of low-density lipoprotein receptor-related protein 1 (LRP1) levels in IPFP-MSC-EXOsTNF-α, thereby exerting chondroprotective effects. CONCLUSION: TNF-α preconditioning constitutes an effective and promising method for optimizing the therapeutic effects of IPFP-MSCs derived exosomes in the treatment of OA.


Asunto(s)
Exosomas , Células Madre Mesenquimatosas , Osteoartritis , Factor de Necrosis Tumoral alfa , Exosomas/metabolismo , Animales , Células Madre Mesenquimatosas/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Ratones , Osteoartritis/terapia , Osteoartritis/metabolismo , Tejido Adiposo/citología , Ratones Endogámicos C57BL , Masculino , Modelos Animales de Enfermedad , Cartílago Articular/metabolismo , Trasplante de Células Madre Mesenquimatosas/métodos , Células Cultivadas , Humanos
20.
Biosci Biotechnol Biochem ; 88(5): 529-537, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38509025

RESUMEN

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.


Asunto(s)
Supervivencia Celular , Cinnamomum , Peróxido de Hidrógeno , Queratinocitos , Potencial de la Membrana Mitocondrial , Mitocondrias , Mitofagia , Estrés Oxidativo , Extractos Vegetales , Especies Reactivas de Oxígeno , Humanos , Mitofagia/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Queratinocitos/citología , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Peróxido de Hidrógeno/metabolismo , Supervivencia Celular/efectos de los fármacos , Cinnamomum/química , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Adenosina Trifosfato/metabolismo , Hojas de la Planta/química , Antioxidantes/farmacología , Ubiquitina-Proteína Ligasas/metabolismo , Sirolimus/farmacología , Células HaCaT , Proteínas Quinasas/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética
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