Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 227
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
J Org Chem ; 89(11): 8023-8034, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38768046

RESUMEN

Herein, we report the Pd(II)-catalyzed direct C-H arylation of pyrrolo[2,3-d]pyrimidine derivatives with aryl iodides, which is enabled by bidentate pyridine-pyridine ligands. A range of aryl iodides proved to be suitable coupling partners affording the desired products in good yields with high levels of C6 selectivity. This protocol features good tolerance of reactive functional groups, mild reaction conditions, and a simple reaction system, which provides an expeditious route to an essential class of 6-arylpyrrolo[2,3-d]pyrimidines frequently found in bioactive compounds, and provides a step-economical access to the second-generation EGFR inhibitor AEE-788.

2.
BMC Med Inform Decis Mak ; 24(1): 15, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38200559

RESUMEN

As the first point of contact for patients, General Practitioners (GPs) play a crucial role in the National Health Service (NHS). An accurate primary diagnosis from the GP can alleviate the burden on specialists and reduce the time needed to re-confirm the patient's condition, allowing for more efficient further examinations. However, GPs have broad but less specialized knowledge, which limits the accuracy of their diagnosis. Therefore, it is imperative to introduce an intelligent system to assist GPs in making decisions. This paper introduces two data augmentation methods, the Complaint Symptoms Integration Method and Symptom Dot Separating Method, to integrate essential information into the Integration dataset. Additionally, it proposes a hybrid architecture that fuses the features of words from different representation spaces. Experiments demonstrate that, compared to commonly used pre-trained attention-based models, our hybrid architecture delivers the best classification performance for four common neurological diseases on the enhanced Integration dataset. For example, the classification accuracy of the BERT+CNN hybrid architecture is 0.897, which is a 5.1% improvement over both BERT and CNN with 0.846. Finally, this paper develops an AI diagnosis assistant web application that leverages the superior performance of this architecture to help GPs complete primary diagnosis efficiently and accurately.


Asunto(s)
Médicos Generales , Medicina Estatal , Humanos , Toma de Decisiones , Inteligencia , Conocimiento
3.
BMC Microbiol ; 23(1): 102, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-37060052

RESUMEN

BACKGROUND: Many studies reported the association between gut microbiota and type 2 diabetes mellitus (T2D), but it is still unclear which bacterial genus plays a key role and how the metabolic function of gut microbiota changes in the occurrence and development of T2D. Besides, there is a high diabetic prevalence in Mongolian population, which may be partly affected by their high calorie diet. This study identified the main bacterial genus influencing T2D in Mongolian population, and analyzed the changes of metabolic function of gut microbiome. The association between dietary factors and the relative abundance of main bacterial genus and its metabolic function was also studied. METHODS: Dietary surveys and gut microbiota test were performed on 24 Mongolian volunteers that were divided into T2D (6 cases), PRET2D (6 cases) and Control group (12 cases) according to fasting plasma glucose (FPG) values. The relative abundance and metabolic function of gut microbiome from their fecal samples were measured by metagenomic analysis. Statistic method was used to evaluate the association between dietary factors and the relative abundance of the main bacterial genus or its metabolic function. RESULTS: This study found that the Clostridium genus may be one of the key bacterial genera affecting the process of T2D. First, the relative abundance of Clostridium genus was significantly different among the three groups. Second, there was a higher relative abundance of metabolic enzymes of gut bacteria in PRET2D and T2D group than that in Control group. Third, a strong correlation between Clostridium genus and many metabolic enzymes was uncovered, many of which may be produced by the Clostridium. Last, carotene intake daily was negatively correlated with the Clostridium but positively correlated with tagaturonate reductase catalyzing interconversions of pentose and glucuronate. CONCLUSIONS: The gut Clostridium genus may play an important role in the development of T2D and it could be a potential biomarker for T2D in Mongolian population. Meanwhile, the metabolic function of gut bacteria has changed during the early stage of T2D and the changes in carbohydrate, amino acid, lipid or energy metabolism of Clostridium genus may play a critical role. In addition, the carotene intake may affect reproduction and metabolic function of Clostridium genus.


Asunto(s)
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Humanos , Glucemia , Dieta , Bacterias/genética , Ayuno
4.
Anal Biochem ; 664: 115045, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36657510

RESUMEN

Cascade reactions catalyzed by natural uricase and mimic peroxidase (MPOD) have been applied for uric acid (UA) detection. However, the optimal catalytic activity of MPOD is mostly in acidic conditions (pH 2-5), mismatching the optimal catalytic alkaline environment of uricase. In this paper, using CuSO4 and urea as raw materials, a MPOD with high catalytic activity in alkaline environment was synthesized by hydrothermal method. Then, based on coupling reaction of uricase/UA/MPOD/guaiacol (GA) system, a novel spectrophotometric method was established to detect 5-60 µmol/L UA (limit of detection = 3.14 µmol/L (S/N = 3)) and accurately quantified serum UA (275.6 ± 39.9 µmol/L, n = 5) with 95-105% of standard addition recovery. The results were consistent with commercial UA kit (p > 0.05). The MPOD could replace natural POD to reduce the cost of UA detection due to simple preparation and cheap raw materials, and is expected to achieve the specific detection of some substances, like glucose and cholesterol, combined with glucose oxidase and cholesterol oxidase.


Asunto(s)
Peroxidasa , Ácido Úrico , Peroxidasa/química , Cobre , Urato Oxidasa/química , Peroxidasas
5.
Environ Sci Technol ; 57(35): 13004-13014, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37526013

RESUMEN

High-resolution mass spectrometry is an advanced technique for comprehensive screening of toxic chemicals. In this study, urine samples were collected from both an occupationally exposed population at a coking site and normal inhabitants to identify novel urinary biomarkers for occupational exposure to coking contaminants. A coking-site-appropriate analytical method was developed for unknown chemical screening. Through nontarget screening, 515 differential features were identified, and finally, 32 differential compounds were confirmed as candidates for the current study, including 13 polycyclic aromatic hydrocarbon (PAH) metabolites. Besides monohydroxy-PAHs (such as 1-&2-naphthol, 2-&9-hydroxyfluorene, 2-&4-phenanthrol, and 1-&2-hydroxypyrene), many other PAH metabolites including dihydroxy metabolites, PAH oxide, and sulfate conjugate were detected, suggesting that the quantification based solely on monohydroxy-PAHs significantly underestimated the human exposure to PAHs. Furthermore, several novel compounds were recognized that could be considered as biomarkers for the exposure to coking contaminants, including quinolin-2-ol (1.10 ± 0.44 ng/mL), naphthylmethanols (11.4 ± 5.47 ng/mL), N-hydroxy-1-aminonaphthalene (0.78 ± 0.43 ng/mL), hydroxydibenzofurans (17.4 ± 7.85 ng/mL), hydroxyanthraquinone (0.13 ± 0.053 ng/mL), and hydroxybiphenyl (2.70 ± 1.03 ng/mL). Despite their lower levels compared with hydroxy-PAHs (95.1 ± 30.8 ng/mL), their severe toxicities should not be overlooked. The study provides a nontarget screening approach to identify chemicals in human urine, which is crucial for accurately assessing the health risks of toxic chemicals in the coking industry.


Asunto(s)
Cocaína , Coque , Exposición Profesional , Hidrocarburos Policíclicos Aromáticos , Humanos , Coque/análisis , Cromatografía Líquida de Alta Presión , Exposición Profesional/análisis , Cocaína/análisis , Biomarcadores , Monitoreo del Ambiente/métodos
6.
Environ Sci Technol ; 57(41): 15379-15391, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37775339

RESUMEN

Coking contamination in China is complex and poses potential health risks to humans. In this study, we collected urine samples from coking plant workers, nearby residents, and control individuals to analyze 25 coking-produced aromatic compounds (ACs), including metabolites of polycyclic aromatic hydrocarbons (PAHs) and their derivatives, chlorophenols, and nitrophenols. The median concentration of total ACs in urine of workers was 102 µg·g-1 creatinine, significantly higher than that in the other two groups. Hydroxy-PAHs and hydroxy hetero-PAHs were the dominant ACs. Workers directly exposed from coking industrial processes, i.e., coking, coal preparation, and chemical production processes, showed higher concentrations of hydroxy-PAHs and hydroxy hetero-PAHs (excluding 5-hydroxyisoquinoline), while those from indirect exposure workshops had higher levels of other ACs, indicating different sources in the coking plant. The AC mixture in workers demonstrated positive effects on DNA damage and lipid peroxidation with 5-hydroxyisoquinoline and 3-hydroxycarbazole playing a significant role using a quantile g-computation model. Monte Carlo simulation revealed that coking contamination elevated the carcinogenic risk for exposed workers by 5-fold compared to controls with pyrene, pentachlorophenol, and carbazole contributing the most, and workers from coking process are at the highest risk. This study enhances understanding of coking-produced AC levels and provides valuable insights into coking contamination control.

7.
BMC Genomics ; 23(1): 507, 2022 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-35831802

RESUMEN

BACKGROUND: Changes in the abundance of ovarian proteins play a key role in the regulation of reproduction. However, to date, no studies have investigated such changes in pubescent goats. Herein we applied isobaric tags for relative and absolute quantitation (iTRAQ) and liquid chromatography-tandem mass spectrometry to analyze the expression levels of ovarian proteins in pre-pubertal (n = 3) and pubertal (n = 3) goats. RESULTS: Overall, 7,550 proteins were recognized; 301 (176 up- and 125 downregulated) were identified as differentially abundant proteins (DAPs). Five DAPs were randomly selected for expression level validation by Western blotting; the results of Western blotting and iTRAQ analysis were consistent. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis indicated that DAPs were enriched in olfactory transduction, glutathione metabolism, and calcium signaling pathways. Besides, gene ontology functional enrichment analysis revealed that several DAPs enriched in biological processes were associated with cellular process, biological regulation, metabolic process, and response to stimulus. Protein-protein interaction network showed that proteins interacting with CDK1, HSPA1A, and UCK2 were the most abundant. CONCLUSIONS: We identified 301 DAPs, which were enriched in olfactory transduction, glutathione metabolism, and calcium signaling pathways, suggesting the involvement of these processes in the onset of puberty. Further studies are warranted to more comprehensively explore the function of the identified DAPs and aforementioned signaling pathways to gain novel, deeper insights into the mechanisms underlying the onset of puberty.


Asunto(s)
Cabras , Proteómica , Animales , Femenino , Glutatión , Ovario , Proteómica/métodos , Maduración Sexual
8.
Reprod Biol Endocrinol ; 20(1): 100, 2022 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-35821045

RESUMEN

Insulin-like growth factor-binding protein-5 (IGFBP-5) has recently been shown to alter the reproductive capacity by regulating insulin-like growth factor (IGF) bioavailability or IGF-independent effects. The present study aimed to investigate the effect and mechanism of IGFBP-5 on the onset of puberty in female rats. Immunofluorescence and real-time quantitative PCR were used to determine the expression and location of IGFBP-5 mRNA and protein distribution in the infant's hypothalamus-pituitary-ovary (HPO) axis prepuberty, peripuberty, puberty and adult female rats. Prepubertal rats with IGFBP-5 intracerebroventricular (ICV) were injected to determine the puberty-related genes expression and the concentrations of reproductive hormones. Primary hypothalamic cells were treated with IGFBP-5 to determine the expression of puberty-related genes and the Akt and mTOR proteins. Results showed that Igfbp-5 mRNA and protein were present on the HPO axis. The addition of IGFBP-5 to primary hypothalamic cells inhibited the expression of Gnrh and Igf-1 mRNAs (P < 0.05) and increased the expression of AKT and mTOR protein (P < 0.01). IGFBP-5 ICV-injection delayed the onset of puberty, reduced Gnrh, Igf-1, and Fshß mRNAs, and decreased the concentrations of E2, P4, FSH,serum LH levels and the ovaries weight (P < 0.05). More corpus luteum and fewer primary follicles were found after IGFBP-5 injection (P < 0.05).


Asunto(s)
Proteína 5 de Unión a Factor de Crecimiento Similar a la Insulina , Pubertad , Animales , Femenino , Hormona Liberadora de Gonadotropina/metabolismo , Proteína 5 de Unión a Factor de Crecimiento Similar a la Insulina/biosíntesis , Proteína 5 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Pubertad/genética , Pubertad/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas
9.
Environ Sci Technol ; 56(12): 8373-8383, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35635317

RESUMEN

Indoor semivolatile organic compounds (SVOCs), present in the air, airborne particles, settled dust, and other indoor surfaces, can enter the human body through several pathways. Knowing the partitioning between gaseous and particulate phases is important in identifying specific pathway contributions and thereby accurately assessing human exposure. Numerous studies have developed equilibrium equations to predict airborne particle/gas (P/G) partitioning in air (KP) and dust/gas (D/G) partitioning in settled dust (KD). The assumption that P/G and D/G equilibria are instantaneous for airborne and settled dust phases, commonly adopted by current indoor fate models, is not likely valid for compounds with high octanol-air partition coefficients (KOA). Here, we develop steady-state based equations to predict KP and KD in the indoor environment. Results show that these equations perform well and are verified by worldwide monitoring data. It is suggested that instantaneous steady state could work for P/G and D/G partitioning of SVOCs in indoor environments, and the equilibrium is just a special case of the steady state when log KOA < 11.38 for P/G partitioning and log KOA < 10.38 for D/G partitioning. These newly developed equations and methods provide a tool for more accurate assessment for human exposure to SVOCs in the indoor environment.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire Interior , Ácidos Ftálicos , Compuestos Orgánicos Volátiles , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Polvo/análisis , Gases , Humanos
10.
Crit Care ; 26(1): 46, 2022 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-35172856

RESUMEN

BACKGROUND: Previous cluster-randomized controlled trials evaluating the impact of implementing evidence-based guidelines for nutrition therapy in critical illness do not consistently demonstrate patient benefits. A large-scale, sufficiently powered study is therefore warranted to ascertain the effects of guideline implementation on patient-centered outcomes. METHODS: We conducted a multicenter, cluster-randomized, parallel-controlled trial in intensive care units (ICUs) across China. We developed an evidence-based feeding guideline. ICUs randomly allocated to the guideline group formed a local "intervention team", which actively implemented the guideline using standardized educational materials, a graphical feeding protocol, and live online education outreach meetings conducted by members of the study management committee. ICUs assigned to the control group remained unaware of the guideline content. All ICUs enrolled patients who were expected to stay in the ICU longer than seven days. The primary outcome was all-cause mortality within 28 days of enrollment. RESULTS: Forty-eight ICUs were randomized to the guideline group and 49 to the control group. From March 2018 to July 2019, the guideline ICUs enrolled 1399 patients, and the control ICUs enrolled 1373 patients. Implementation of the guideline resulted in significantly earlier EN initiation (1.20 vs. 1.55 mean days to initiation of EN; difference - 0.40 [95% CI - 0.71 to - 0.09]; P = 0.01) and delayed PN initiation (1.29 vs. 0.80 mean days to start of PN; difference 1.06 [95% CI 0.44 to 1.67]; P = 0.001). There was no significant difference in 28-day mortality (14.2% vs. 15.2%; difference - 1.6% [95% CI - 4.3% to 1.2%]; P = 0.42) between groups. CONCLUSIONS: In this large-scale, multicenter trial, active implementation of an evidence-based feeding guideline reduced the time to commencement of EN and overall PN use but did not translate to a reduction in mortality from critical illness. TRIAL REGISTRATION: ISRCTN, ISRCTN12233792 . Registered November 20th, 2017.


Asunto(s)
Enfermedad Crítica , Apoyo Nutricional , China , Enfermedad Crítica/terapia , Humanos , Unidades de Cuidados Intensivos , Factores de Tiempo
11.
Int J Mol Sci ; 23(7)2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35409158

RESUMEN

Psoriasis is an immune disease caused by rapid and incomplete differentiation of skin basal cells. Natural products such as indirubin have historically served as excellent sources for the treatments of psoriasis. However, the poor solubility and bioavailability due to its plane and rigid crystal structure, which limits its efficacy. Herein, to improve the efficacy of indirubin, a hydrogel-based microemulsion drug delivery system was developed for transdermal delivery. The mean droplet size of the optimized microemulsion was 84.37 nm, with a polydispersity index (PDI) less than 0.2 and zeta potential value of 0~-20 mV. The transdermal flux and skin retention of indirubin at 24 h were 47.34 ± 3.59 µg/cm2 and 8.77 ± 1.26 µg/cm2, respectively. The optimized microemulsion was dispersed in carbomer 934 hydrogel to increase the consistency. The indirubin-loaded microemulsion gel was tested on an imiquimod-induced psoriasis mouse model. Results showed that this preparation can improve psoriasis symptoms by down-regulating the expression of IL-17A, Ki67, and CD4+T. This experiment provides great scalability for researchers to treat psoriasis, avoid first-pass effects, and increase the concentration of targeted drugs.


Asunto(s)
Psoriasis , Administración Cutánea , Animales , Emulsiones/química , Hidrogeles/química , Indoles , Ratones , Psoriasis/tratamiento farmacológico
12.
Chin Med Sci J ; 37(3): 171-180, 2022 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-36321172

RESUMEN

Objective To explore the semi-supervised learning (SSL) algorithm for long-tail endoscopic image classification with limited annotations. Method We explored semi-supervised long-tail endoscopic image classification in HyperKvasir, the largest gastrointestinal public dataset with 23 diverse classes. Semi-supervised learning algorithm FixMatch was applied based on consistency regularization and pseudo-labeling. After splitting the training dataset and the test dataset at a ratio of 4:1, we sampled 20%, 50%, and 100% labeled training data to test the classification with limited annotations. Results The classification performance was evaluated by micro-average and macro-average evaluation metrics, with the Mathews correlation coefficient (MCC) as the overall evaluation. SSL algorithm improved the classification performance, with MCC increasing from 0.8761 to 0.8850, from 0.8983 to 0.8994, and from 0.9075 to 0.9095 with 20%, 50%, and 100% ratio of labeled training data, respectively. With a 20% ratio of labeled training data, SSL improved both the micro-average and macro-average classification performance; while for the ratio of 50% and 100%, SSL improved the micro-average performance but hurt macro-average performance. Through analyzing the confusion matrix and labeling bias in each class, we found that the pseudo-based SSL algorithm exacerbated the classifier's preference for the head class, resulting in improved performance in the head class and degenerated performance in the tail class. Conclusion SSL can improve the classification performance for semi-supervised long-tail endoscopic image classification, especially when the labeled data is extremely limited, which may benefit the building of assisted diagnosis systems for low-volume hospitals. However, the pseudo-labeling strategy may amplify the effect of class imbalance, which hurts the classification performance for the tail class.


Asunto(s)
Algoritmos , Aprendizaje Automático Supervisado
13.
Acta Pharmacol Sin ; 42(10): 1556-1566, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33495516

RESUMEN

Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder caused by toxic aggregates of mutant huntingtin protein (mHTT) in the brain. Decreasing mHTT is a potential strategy for therapeutic purpose of HD. Valosin-containing protein (VCP/p97) is a crucial regulator of proteostasis, which regulates the degradation of damaged protein through proteasome and autophagy pathway. Since VCP has been implicated in pathogenesis of HD as well as other neurodegenerative diseases, small molecules that specifically regulate the activity of VCP may be of therapeutic benefits for HD patients. In this study we established a high-throughput screening biochemical assay for VCP ATPase activity measurement and identified gossypol, a clinical approved drug in China, as a novel modulator of VCP. Gossypol acetate dose-dependently inhibited the enzymatic activity of VCP in vitro with IC50 of 6.53±0.6 µM. We further demonstrated that gossypol directly bound to the interface between the N and D1 domains of VCP. Gossypol acetate treatment not only lowered mHTT levels and rescued HD-relevant phenotypes in HD patient iPS-derived Q47 striatal neurons and HD knock-in mouse striatal cells, but also improved motor function deficits in both Drosophila and mouse HD models. Taken together, gossypol acetate acted through a gain-of-function way to induce the formation of VCP-LC3-mHTT ternary complex, triggering autophagic degradation of mHTT. This study reveals a new strategy for treatment of HD and raises the possibility that an existing drug can be repurposed as a new treatment of neurodegenerative diseases.


Asunto(s)
Autofagia/efectos de los fármacos , Gosipol/uso terapéutico , Proteína Huntingtina/metabolismo , Enfermedad de Huntington/tratamiento farmacológico , Fármacos Neuroprotectores/uso terapéutico , Animales , Drosophila , Inhibidores Enzimáticos/uso terapéutico , Femenino , Células HEK293 , Células HeLa , Humanos , Proteína Huntingtina/química , Proteína Huntingtina/genética , Masculino , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Mutación , Multimerización de Proteína/efectos de los fármacos , Proteolisis/efectos de los fármacos , Proteína que Contiene Valosina/antagonistas & inhibidores , Proteína que Contiene Valosina/metabolismo
14.
Ann Noninvasive Electrocardiol ; 26(6): e12874, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34250699

RESUMEN

BACKGROUND: Accumulated evidence has indicated that a high-normal FT4 level is an independent risk factor for the clinical progression of AF. However, the association between elevated FT4 concentration within the normal range and AF recurrence after cryoballoon ablation in China is unknown. METHODS: This retrospective and observational study included 453 AF patients who underwent cryoballoon ablation from January 2016 to August 2018. Patients were classified into quartiles based on preprocedural serum FT4 concentration. The clinical characteristics of the patients and the long-term rate of AF recurrence after ablation were assessed. RESULTS: After a mean follow-up period of 17.4 ± 9.0 months, 91 (20.1%) patients suffered from AF recurrence. The AF recurrence rate by FT4 quartile was 17.7%, 19.0%, 21.4%, and 22.3% for participants with FT4 in quartile 1, 2, 3, and 4, respectively (p < .001). On multivariate Cox regression, FT4 concentration (HR: 1.187, 95% CI: 1.093-1.290, p < .001) and left atrial diameter (HR: 1.052, 95% CI: 1.014-1.092, p = .007) were significant predictors of AF recurrence. When stratifying for AF type, the rate of postoperative recurrence was independently increased as FT4 concentration increased in paroxysmal AF, but not in persistent AF (p < .001 in paroxysmal AF and p = .977 in persistent AF). CONCLUSION: Higher FT4 level within the normal range predicted the outcome of cryoballoon ablation in Chinese paroxysmal AF patients without structural heart disease.


Asunto(s)
Fibrilación Atrial , Criocirugía , Fibrilación Atrial/cirugía , Electrocardiografía , Humanos , Recurrencia , Valores de Referencia , Estudios Retrospectivos , Resultado del Tratamiento
15.
Cryobiology ; 103: 49-56, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34648777

RESUMEN

A significant proportion of patients with recurrent atrial fibrillation (AF) require repeat radiofrequency (RF) ablation after cryoballoon (CB) ablation. However, little is known about the pulmonary vein (PV) potential reconnection to left atrium and localization of gaps in the initial lesion sets following cryoablation in patients with recurrent AF. The data of 29 consecutive patients with repeat RF ablation for recurrent AF were analyzed. During the second ablation procedures, PV foci of AF were explored in 116 PVs by the CARTO system. All patients had complete PV isolation from initial cryoablation procedure. The fluoroscopy duration, mean cryoablation time and mean cryoablation frequency were lowest for the right superior pulmonary vein (RSPV) (58.69 ± 9.18 s, 185.10 ± 49.25 s and 1.07 ± 0.26; p = 0.024, p = 0.042 and p = 0.032). A significantly higher incidence of conduction gaps per patient was found for the RSPVs compared to the other PVs (p < 0.05 or p < 0.01). For RSPVs, it seemed that gaps were predominantly located at the anterior segment (22 gaps) and inferior segment (22 gaps). RSPV reconnection was independently related to a lower risk of major adverse events after the second ablation during follow up in the study patients (HR 0.275, 95%CI 0.078-0.967, p = 0.044). AF recurrence in patients after cryoablation is significantly associated with conduction gaps in the anterior and inferior segments of RSPVs. Various ablation strategies of close touch of CB on anterior and inferior segments of RSPV ostium, more freezing time and frequency for RSPV may help achieving durable PV isolation during follow up.


Asunto(s)
Fibrilación Atrial , Criocirugía , Venas Pulmonares , Fibrilación Atrial/cirugía , Criopreservación/métodos , Atrios Cardíacos , Humanos , Venas Pulmonares/cirugía , Recurrencia , Resultado del Tratamiento
16.
J Cardiovasc Electrophysiol ; 31(11): 2865-2873, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33405334

RESUMEN

BACKGROUND: Acute left atrial ridge (LAR) lesions have been observed following atrial fibrillation (AF) ablation. However, LAR lesions had not yet been quantitatively evaluated and their influence on procedure combining cryoballoon (CB) ablation with left atrial appendage closure (LAAC) remained to be explored. METHODS: The profile of LAR lesions was measured by transesophageal echocardiography (TEE) in 117 consecutive nonvalvular AF patients, who underwent the combined procedure of CB ablation and LAAC. We thoroughly investigated how LAR lesions correlated with baseline variables and clinical outcomes. RESULTS: A total of 95 out of 96 available TEE images presented prominent acute LAR lesions. In terms of dimensions, there was a greater change in width (Δwidth = 3.6 ± 2.3 mm) than the thickness (Δthickness = 2.6 ± 3.5 mm), and the outer ostium was narrowed (Δouter ostium diameter = -3.4 ± 4.0 mm), while the inner ostium remained unchanged. A higher nadir temperature when freezing the left superior pulmonary vein (LSPV) led to an LAR lesion with a two times greater width (adjusted odds ratio = 1.16; 95% confidence interval, 1.02-1.31). In the evaluation of LAAC outcomes, four patients implanted with Watchman devices had minimal residual flow at the inferior border, while two implanted with LAmbre devices developed residual flow at the LAR side. Clinical outcomes were similar between groups divided by lesion size. CONCLUSION: Acute LAR lesions frequently occurred following the CB ablation combined procedure, and lesion width positively correlates with LSPV nadir temperature. The presence of these lesions affects the measurement of pacifier devices but has little impact on that of occluder devices.


Asunto(s)
Apéndice Atrial , Fibrilación Atrial , Ablación por Catéter , Venas Pulmonares , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/cirugía , Fibrilación Atrial/diagnóstico por imagen , Fibrilación Atrial/cirugía , Humanos , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/cirugía , Resultado del Tratamiento
17.
Nitric Oxide ; 104-105: 11-19, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32827754

RESUMEN

Irreversible aggregation can extremely limit the bioavailability and therapeutic activity of peptide-based drugs. There is therefore an urgent demand of effective strategy to control peptide aggregation. Recently, we found that tyrosine nitration at certain sites of peptide can effectively inhibit its aggregation. This minor modification may be an ideal strategy to the rational design of peptide-based drugs with low aggregation propensity yet without loss of bioactivity. Human calcitonin (hCT) is such a peptide hormone known for its hypocalcaemic effect but has limited pharmaceutical potential due to a high tendency to aggregate. In this study, by using multiple techniques including Fluorescence, TEM, Nu-PAGE and CD, we demonstrated that Y12 nitration of hCT would significantly inhibit its self-assembles, and we also found that this modification would not only reduce the cytotoxicity induced by peptide aggregation, but also had little effect on its potency. This finding may provide a novel strategy for clinically application of hCT instead of sCT.


Asunto(s)
Calcitonina/farmacología , Nitrobencenos/química , Multimerización de Proteína/efectos de los fármacos , Tirosina/química , Secuencia de Aminoácidos , Animales , Calcitonina/química , Calcitonina/fisiología , Calcio/metabolismo , Línea Celular Tumoral , Femenino , Humanos , Ratones , Conformación Proteica en Lámina beta/efectos de los fármacos
18.
Clin Sci (Lond) ; 133(5): 611-627, 2019 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-30782608

RESUMEN

Cardiac hypertrophy is a common pathophysiological process in various cardiovascular diseases, which still has no effective therapies. Irisin is a novel myokine mainly secreted by skeletal muscle and is believed to be involved in the regulation of energy metabolism. In the present study, we found that irisin expression was elevated in hypertrophic murine hearts and serum. Moreover, angiotension II-induced cardiomyocyte hypertrophy was attenuated after irisin administration and aggravated after irisin knockdown in vitro Next, we generated transverse aortic constriction (TAC)-induced cardiac hypertrophy murine model and found that cardiac hypertrophy and fibrosis were significantly attenuated with improved cardiac function assessed by echocardiography after irisin treatment. Mechanistically, we demonstrated that FNDC5 was cleaved into irisin, at least partially, in a disintegrin and metalloproteinase (ADAM) family-dependent manner. ADAM10 was the candidate enzyme responsible for the cleavage. Further, we found irisin treatment activated AMPK and subsequently inhibited activation of mTOR. AMPK inhibition ablated the protective role of irisin administration. In conclusion, we find irisin is secreted in an ADAM family-dependent manner, and irisin treatment improves cardiac function and attenuates pressure overload-induced cardiac hypertrophy and fibrosis mainly through regulating AMPK-mTOR signaling.


Asunto(s)
Cardiomegalia/metabolismo , Fibronectinas/metabolismo , Miocitos Cardíacos/metabolismo , Remodelación Ventricular , Proteína ADAM10/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Anciano , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Animales , Cardiomegalia/patología , Cardiomegalia/fisiopatología , Cardiomegalia/prevención & control , Estudios de Casos y Controles , Línea Celular , Modelos Animales de Enfermedad , Femenino , Fibronectinas/genética , Fibrosis , Humanos , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Persona de Mediana Edad , Miocitos Cardíacos/patología , Ratas Sprague-Dawley , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
19.
FASEB J ; 32(2): 1070-1084, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29070585

RESUMEN

NOD-like receptor family caspase recruitment domain family domain containing 5 (NLRC5) has important roles in inflammation and innate immunity. NLRC5 was highly expressed in kidney from streptozotocin-induced diabetic mice, db/ db mice and patients with diabetes. Based on that evidence, the present study was designed to explore the roles of NLRC5 in the progression of diabetic nephropathy (DN). We examined kidney injury, including inflammation and fibrosis in Nlrc5 gene knockout ( Nlrc5-/-) and wild-type (WT) diabetic mice. We found that Nlrc5-/- mice developed less-severe diabetic kidney injury compared with WT mice, exhibiting lower albuminuria, less fibronectin and collagen IV expression, and reduced macrophage infiltration but greater levels of podocin and nephrin in the diabetic kidney. The underlying mechanisms were further investigated in vitro with peritoneal macrophages and mesangial cells treated with high glucose. Reduced proinflammatory effect was observed in peritoneal macrophages from Nlrc5-/- mice, associated with NF-κB pathway suppression. Knocking down of NLRC5 in mesangial cells in high-glucose conditions was also associated with reduced NF-κB and TGF-ß/Smad signaling. Taken together, NLRC5 promotes inflammation and fibrosis during DN progression partly through the effects on NF-κB and TGF-ß/Smad pathways. NLRC5 may, therefore, be a promising therapeutic target for DN treatment.-Luan, P., Zhuang, J., Zou, J., Li, H., Shuai, P., Xu, X., Zhao, Y., Kou, W., Ji, S., Peng, A., Xu, Y., Su, Q., Jian, W., Peng, W. NLRC5 deficiency ameliorates diabetic nephropathy through alleviating inflammation.


Asunto(s)
Diabetes Mellitus Experimental/metabolismo , Nefropatías Diabéticas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/deficiencia , Células Mesangiales/metabolismo , Transducción de Señal , Animales , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patología , Nefropatías Diabéticas/genética , Nefropatías Diabéticas/patología , Femenino , Humanos , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Masculino , Células Mesangiales/patología , Ratones , Ratones Noqueados , FN-kappa B/genética , FN-kappa B/metabolismo , Proteínas Smad/genética , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/metabolismo
20.
Nitric Oxide ; 91: 42-51, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31351146

RESUMEN

Water-soluble iron porphyrins, such as FeTPPS (5,10,15,20-tetrakis (4-sulfonatophenyl) porphyrinato iron (III)), FeTMPyP (5,10,15,20-tetrakis (N-methyl-4'-pyridyl) porphyrinato iron (III) chloride) and FeTBAP (5,10,15,20-tetrakis (4-benzoic acid) porphyrinato iron (III)), are highly active catalysts for peroxynitrite decomposition and thereby have been suggested as therapeutic agent for inflammatory diseases that implicate the involvement of nitrotyrosine formation. Here, we systemically investigated catalytic properties of FeTPPS, FeTMPyP and FeTBAP on protein nitration in the presence of hydrogen peroxide and nitrite. We showed that FeTPPS, FeTBAP and FeTMPyP all exhibited higher peroxidase activity in compared with hemin. As to protein nitration, the catalytic effect of FeTPPS and FeTBAP are effective in the presence of hydrogen peroxide and nitrite, while negligible BSA nitration was observed in the case of FeTMPyP. Moreover, the underlying mechanism of the oxidation of FeTPPS, FeTBAP and FeTMPyP was further studied. Collectively, our results suggest that, compound I and II species are involved in as the key intermediates in FeTMPyP/H2O2 system as similar as those in FeTPPS/H2O2 and FeTBAP/H2O2 system. As compared to weak antioxidants, TPPS and TBAP, however, TMPyP scavenges oxo-Fe (IV) intermediates of FeTMPyP at a faster rate by significant self-degradation; results in the shortest lifetimes of OFeIV-TMPyP and the lowest catalytic activity on oxidizing tyrosine and nitrite; and therefore, attributes to inactivation of FeTMPyP in protein nitration. In addition, association of FeTMPyP to BSA was found weak, while strong binding of FeTPPS and FeTBAP were observed. The weak binding keeps away of target residue of BSA from the center of FeTMPyP where the RNS is generated, which might be attributed as additional factors to the inactivation of FeTMPyP in protein nitration.


Asunto(s)
Peróxido de Hidrógeno/química , Metaloporfirinas/química , Nitratos/química , Nitritos/química , Albúmina Sérica Bovina/metabolismo , Tirosina/química , Animales , Catálisis , Bovinos , Peroxidasa/química , Ácido Peroxinitroso/metabolismo , Albúmina Sérica Bovina/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA