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1.
Cell ; 186(10): 2193-2207.e19, 2023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37098343

RESUMEN

Somatic hypermutation (SHM), initiated by activation-induced cytidine deaminase (AID), generates mutations in the antibody-coding sequence to allow affinity maturation. Why these mutations intrinsically focus on the three nonconsecutive complementarity-determining regions (CDRs) remains enigmatic. Here, we found that predisposition mutagenesis depends on the single-strand (ss) DNA substrate flexibility determined by the mesoscale sequence surrounding AID deaminase motifs. Mesoscale DNA sequences containing flexible pyrimidine-pyrimidine bases bind effectively to the positively charged surface patches of AID, resulting in preferential deamination activities. The CDR hypermutability is mimicable in in vitro deaminase assays and is evolutionarily conserved among species using SHM as a major diversification strategy. We demonstrated that mesoscale sequence alterations tune the in vivo mutability and promote mutations in an otherwise cold region in mice. Our results show a non-coding role of antibody-coding sequence in directing hypermutation, paving the way for the synthetic design of humanized animal models for optimal antibody discovery and explaining the AID mutagenesis pattern in lymphoma.


Asunto(s)
Citidina Desaminasa , Hipermutación Somática de Inmunoglobulina , Animales , Ratones , Anticuerpos/genética , Citidina Desaminasa/genética , Citidina Desaminasa/metabolismo , ADN/genética , ADN de Cadena Simple , Mutación , Evolución Molecular , Regiones Determinantes de Complementariedad/genética , Motivos de Nucleótidos
2.
Cell ; 184(21): 5357-5374.e22, 2021 10 14.
Artículo en Inglés | MEDLINE | ID: mdl-34582788

RESUMEN

Despite remarkable clinical efficacy of immune checkpoint blockade (ICB) in cancer treatment, ICB benefits for triple-negative breast cancer (TNBC) remain limited. Through pooled in vivo CRISPR knockout (KO) screens in syngeneic TNBC mouse models, we found that deletion of the E3 ubiquitin ligase Cop1 in cancer cells decreases secretion of macrophage-associated chemokines, reduces tumor macrophage infiltration, enhances anti-tumor immunity, and strengthens ICB response. Transcriptomics, epigenomics, and proteomics analyses revealed that Cop1 functions through proteasomal degradation of the C/ebpδ protein. The Cop1 substrate Trib2 functions as a scaffold linking Cop1 and C/ebpδ, which leads to polyubiquitination of C/ebpδ. In addition, deletion of the E3 ubiquitin ligase Cop1 in cancer cells stabilizes C/ebpδ to suppress expression of macrophage chemoattractant genes. Our integrated approach implicates Cop1 as a target for improving cancer immunotherapy efficacy in TNBC by regulating chemokine secretion and macrophage infiltration in the tumor microenvironment.


Asunto(s)
Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Inmunoterapia , Macrófagos/enzimología , Neoplasias/inmunología , Neoplasias/terapia , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Proteína delta de Unión al Potenciador CCAAT/metabolismo , Proteína 9 Asociada a CRISPR/metabolismo , Línea Celular Tumoral , Quimiocinas/metabolismo , Quimiotaxis , Modelos Animales de Enfermedad , Biblioteca de Genes , Humanos , Evasión Inmune , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Proteolisis , Especificidad por Sustrato , Neoplasias de la Mama Triple Negativas/inmunología , Neoplasias de la Mama Triple Negativas/terapia
3.
Mol Cell ; 81(6): 1292-1308.e11, 2021 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-33567269

RESUMEN

The ubiquitin-proteasome system (UPS) is the primary route for selective protein degradation in human cells. The UPS is an attractive target for novel cancer therapies, but the precise UPS genes and substrates important for cancer growth are incompletely understood. Leveraging multi-omics data across more than 9,000 human tumors and 33 cancer types, we found that over 19% of all cancer driver genes affect UPS function. We implicate transcription factors as important substrates and show that c-Myc stability is modulated by CUL3. Moreover, we developed a deep learning model (deepDegron) to identify mutations that result in degron loss and experimentally validated the prediction that gain-of-function truncating mutations in GATA3 and PPM1D result in increased protein stability. Last, we identified UPS driver genes associated with prognosis and the tumor microenvironment. This study demonstrates the important role of UPS dysregulation in human cancer and underscores the potential therapeutic utility of targeting the UPS.


Asunto(s)
Aprendizaje Profundo , Modelos Genéticos , Mutación , Proteínas de Neoplasias , Neoplasias , Proteolisis , Línea Celular Tumoral , Células HEK293 , Humanos , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias/genética , Neoplasias/metabolismo
4.
Mol Cell ; 78(6): 1096-1113.e8, 2020 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-32416067

RESUMEN

BET bromodomain inhibitors (BBDIs) are candidate therapeutic agents for triple-negative breast cancer (TNBC) and other cancer types, but inherent and acquired resistance to BBDIs limits their potential clinical use. Using CRISPR and small-molecule inhibitor screens combined with comprehensive molecular profiling of BBDI response and resistance, we identified synthetic lethal interactions with BBDIs and genes that, when deleted, confer resistance. We observed synergy with regulators of cell cycle progression, YAP, AXL, and SRC signaling, and chemotherapeutic agents. We also uncovered functional similarities and differences among BRD2, BRD4, and BRD7. Although deletion of BRD2 enhances sensitivity to BBDIs, BRD7 loss leads to gain of TEAD-YAP chromatin binding and luminal features associated with BBDI resistance. Single-cell RNA-seq, ATAC-seq, and cellular barcoding analysis of BBDI responses in sensitive and resistant cell lines highlight significant heterogeneity among samples and demonstrate that BBDI resistance can be pre-existing or acquired.


Asunto(s)
Resistencia a Antineoplásicos/genética , Proteínas/antagonistas & inhibidores , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Animales , Antineoplásicos/farmacología , Azepinas/farmacología , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proteínas Cromosómicas no Histona/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Ratones Endogámicos NOD , Proteínas Nucleares/metabolismo , Proteínas/metabolismo , Transducción de Señal/efectos de los fármacos , Factores de Transcripción/metabolismo , Triazoles/farmacología , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/metabolismo
5.
Cell Mol Life Sci ; 81(1): 118, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38448737

RESUMEN

Tektins are microtubule inner proteins (MIPs) and localize at the inside lumen of doublet microtubules (DMTs) of cilia/flagella. TEKTIP1, a newly identified protein by cryo-electron microscopy (cryo-EM), is proposed to be localized at the center of the tektin bundle and hypothesized to recruit tektins or stabilize the bundle. However, the physiological role of TEKTIP1 is unknown. In this study, we generated Tektip1-knockout (Tektip1-/-) mice and showed that they were male subfertile primarily due to reduced sperm motility. A high percentage of sperm from Tektip1-/- mice showed moderately disorganized axoneme structures and abnormal flagellar waveforms. TEKTIP1 predominately interacted with TEKT3 among tektins. Loss of TEKTIP1 partially disturbed the organization of tektin bundle by mainly affecting the native status of TEKT3 and its interaction with other tektins. Collectively, our study reveals the physiological role and potential molecular mechanism of TEKTIP1 in axonemal structure and sperm motility, highlights the importance of MIPs in stabilizing DMTs, and suggests a potential relevance of TEKTIP1 deficiency to human asthenospermia. Tektip1-/- mice will be an excellent animal model to study the DMT organization of sperm flagella using cryo-EM in future.


Asunto(s)
Axonema , Proteínas de Microtúbulos , Semen , Humanos , Masculino , Animales , Ratones , Femenino , Microscopía por Crioelectrón , Motilidad Espermática , Espermatozoides , Flagelos
6.
Proc Natl Acad Sci U S A ; 119(45): e2208505119, 2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36322772

RESUMEN

The linear positive magnetoresistance (LPMR) is a widely observed phenomenon in topological materials, which is promising for potential applications on topological spintronics. However, its mechanism remains ambiguous yet, and the effect is thus uncontrollable. Here, we report a quantitative scaling model that correlates the LPMR with the Berry curvature, based on a ferromagnetic Weyl semimetal CoS2 that bears the largest LPMR of over 500% at 2 K and 9 T, among known magnetic topological semimetals. In this system, masses of Weyl nodes existing near the Fermi level, revealed by theoretical calculations, serve as Berry-curvature monopoles and low-effective-mass carriers. Based on the Weyl picture, we propose a relation [Formula: see text], with B being the applied magnetic field and [Formula: see text] the average Berry curvature near the Fermi surface, and further introduce temperature factor to both MR/B slope (MR per unit field) and anomalous Hall conductivity, which establishes the connection between the model and experimental measurements. A clear picture of the linearly slowing down of carriers, i.e., the LPMR effect, is demonstrated under the cooperation of the k-space Berry curvature and real-space magnetic field. Our study not only provides experimental evidence of Berry curvature-induced LPMR but also promotes the common understanding and functional designing of the large Berry-curvature MR in topological Dirac/Weyl systems for magnetic sensing or information storage.

7.
Nano Lett ; 24(31): 9583-9590, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39041791

RESUMEN

Thanks to their tunable infrared absorption, solution processability, and low fabrication costs, HgTe colloidal quantum dots (CQDs) are promising for optoelectronic devices. Despite advancements in device design, their potential for imaging applications remains underexplored. For integration with Si-based readout integrated circuits (ROICs), top illumination is necessary for simultaneous light absorption and signal acquisition. However, most high-performing traditional HgTe CQD photodiodes are p-on-n stack and bottom-illuminated. Herein, we report top-illuminated inverted n-on-p HgTe CQD photodiodes using a robust p-type CQD layer and a thermally evaporated Bi2S3 electron transport layer. The p-type CQD solid is achieved by exploring the synergism in binary HgTe and Ag2Te CQDs. These photodetectors show a room-temperature detectivity of 3.4 × 1011 jones and an EQE of ∼44% at ∼1.7 µm wavelength, comparable to the p-on-n HgTe CQD photodiodes. A top-illuminated HgTe CQD short-wave infrared imager (640 × 512 pixels) was fabricated, demonstrating successful infrared imaging.

8.
Anal Chem ; 96(25): 10200-10209, 2024 06 25.
Artículo en Inglés | MEDLINE | ID: mdl-38867357

RESUMEN

Rapid tissue differentiation at the molecular level is a prerequisite for precise surgical resection, which is of special value for the treatment of malignant tumors, such as glioblastoma (GBM). Herein, a SERS-active microneedle is prepared by modifying glutathione (GSH)-responsive molecules, 5,5'-dithiobis(2-nitrobenzoic acid) (DTNB), on the surface of Au@Ag substrates for the distinction of different GBM tissues. Since the Raman signals on the surface of the DTNB@Au@Ag microneedle can be collected by both portable and benchtop Raman spectrometers, the distribution of GSH in different tissues at centimeter scale can be displayed through Raman spectroscopy and Raman imaging, and the entire analysis process can be accomplished within 12 min. Accordingly, in vivo brain tissues of orthotopic GBM xenograft mice and ex vivo tissues of GBM patients are accurately differentiated with the microneedle, and the results are well consistent with tissue staining and postoperative pathological reports. In addition, the outline of tumor, peritumoral, and normal tissues can be indicated by the DTNB@Au@Ag microneedle for at least 56 days. Considering that the tumor tissues are quickly discriminated at the molecular level without the restriction of depth, the DTNB@Au@Ag microneedle is promising to be a powerful intraoperative diagnostic tool for surgery navigation.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Glutatión , Oro , Espectrometría Raman , Glioblastoma/patología , Glioblastoma/metabolismo , Glioblastoma/diagnóstico por imagen , Animales , Humanos , Glutatión/análisis , Glutatión/metabolismo , Oro/química , Ratones , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/diagnóstico por imagen , Agujas , Plata/química , Ratones Desnudos , Ácido Ditionitrobenzoico/química , Línea Celular Tumoral , Nanopartículas del Metal/química
9.
Biochem Biophys Res Commun ; 703: 149665, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38359612

RESUMEN

BACKGROUND: Intrinsic brain tumours such as glioblastoma (GBM) are believed to develop from neuroglial stem or progenitor cells. GBM accounts for approximately half of gliomas. GBM has a poor prognosis and a low 5-year survival rate. Pentraxin 3 (PTX3) is overexpressed in GBM, but the potential mechanism is unclear. METHODS: Glioblastoma data from the TCGA and CGGA databases were used to analyse PTX3 expression. Subsequently, in vivo and in vitro experiments were conducted to verify the effect of PTX3 silencing in glioma cells on EMT like process and GSC maintenance. The JASPAR database was used to predict the downstream genes of PTX3. POSTN is a novel target gene of PTX3 in gliomas, and this finding was validated using a luciferase reporter gene assay. Western blotting and KEGG enrichment analysis were used to predict the downstream pathway of POSTN, and it was found that the MAPK/ERK pathway might be related to the function of POSTN. RESULTS: GBM tissues have higher levels of PTX3 expression than normal brain tissues (NBTs). In functional tests, PTX3 promoted the EMT like process of GBM cells while maintaining the stem cell characteristics of GBM stem cells and enhancing their self-renewal. Moreover, we performed a dual luciferase reporter experiment to confirm that PTX3 binds to the POSTN promoter region. In addition, the expression of key proteins in the MAPK/ERK signalling pathway was increased after PTX3 overexpression. CONCLUSION: POSTN is a direct target of PTX3 that promotes GBM growth via the MAPK/ERK signalling pathway.


Asunto(s)
Neoplasias Encefálicas , Proteína C-Reactiva , Glioblastoma , Glioma , Componente Amiloide P Sérico , Humanos , Glioblastoma/patología , Glioma/genética , Neoplasias Encefálicas/patología , Luciferasas/metabolismo , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Moléculas de Adhesión Celular/metabolismo
10.
Cancer Immunol Immunother ; 73(6): 112, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38693422

RESUMEN

OBJECTIVE: The high mortality rate of gastric cancer, traditionally managed through surgery, underscores the urgent need for advanced therapeutic strategies. Despite advancements in treatment modalities, outcomes remain suboptimal, necessitating the identification of novel biomarkers to predict sensitivity to immunotherapy. This study focuses on utilizing single-cell sequencing for gene identification and developing a random forest model to predict immunotherapy sensitivity in gastric cancer patients. METHODS: Differentially expressed genes were identified using single-cell RNA sequencing (scRNA-seq) and gene set enrichment analysis (GESA). A random forest model was constructed based on these genes, and its effectiveness was validated through prognostic analysis. Further, analyses of immune cell infiltration, immune checkpoints, and the random forest model provided deeper insights. RESULTS: High METTL1 expression was found to correlate with improved survival rates in gastric cancer patients (P = 0.042), and the random forest model, based on METTL1 and associated prognostic genes, achieved a significant predictive performance (AUC = 0.863). It showed associations with various immune cell types and negative correlations with CTLA4 and PDCD1 immune checkpoints. Experiments in vitro and in vivo demonstrated that METTL1 enhances gastric cancer cell activity by suppressing T cell proliferation and upregulating CTLA4 and PDCD1. CONCLUSION: The random forest model, based on scRNA-seq, shows high predictive value for survival and immunotherapy sensitivity in gastric cancer patients. This study underscores the potential of METTL1 as a biomarker in enhancing the efficacy of gastric cancer immunotherapy.


Asunto(s)
Inmunoterapia , Análisis de la Célula Individual , Neoplasias Gástricas , Neoplasias Gástricas/genética , Neoplasias Gástricas/terapia , Neoplasias Gástricas/inmunología , Neoplasias Gástricas/mortalidad , Humanos , Análisis de la Célula Individual/métodos , Inmunoterapia/métodos , Animales , Ratones , Pronóstico , Biomarcadores de Tumor/genética , Análisis de Secuencia de ARN/métodos , Femenino , Masculino , Regulación Neoplásica de la Expresión Génica , Ensayos Antitumor por Modelo de Xenoinjerto , Línea Celular Tumoral , Bosques Aleatorios
11.
Langmuir ; 40(25): 13265-13275, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38857070

RESUMEN

Artificial photoelectrochemistry (PEC) has emerged as a promising and efficient technology for the sustainable conversion of solar energy into chemicals. In this study, we present a refined PEC process that enables the highly selective and stable production of piperonal and other valuable aldehydes through the oxidation of the corresponding alcohols. By employing Fe2O3 or TiO2 as the photoanode material and 2,2,6,6-tetramethylpiperidinooxy (TEMPO) as a redox mediator in an H2O/acetonitrile solution, we achieve 100% selectivity and a >95% Faradaic efficiency for piperonal production from piperonyl alcohol (PA) oxidation. Remarkably, we reveal the enhancing effect on the PA oxidation reactivity of appropriate-amount water in the solvent as it plays a crucial role in inhibiting the photoelectron-hole recombination efficiency and facilitating charge transfer. Mechanistic analysis suggests that TEMPO-mediated PA oxidation involves the formation of •O2- radicals by the reduction of oxygen on the cathode, resulting in water as the sole byproduct. Furthermore, our PEC oxidation system exhibits applications on the 100%-selective production of various conjugated aldehydes, including 4-anisaldehyde, cuminaldehyde, and the vitamin B6 derivative. By implementing a TiO2//Fe2O3 dual-photoanode system, we achieve an enhanced piperonal production rate of 31.2 µmol h-1 cm-2 at 1.0 V vs Ag/Ag+ and demonstrate its stability over a 102 h cyclic test, ensuring near-quantitative yield. This research illuminates the potential of the PEC strategy as a generally applicable method for the efficient production of high-value aldehydes.

12.
Liver Int ; 44(1): 155-168, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-37804070

RESUMEN

BACKGROUND AND AIMS: Sarcopenia is associated with poor prognosis, but its role in older patients with intrahepatic cholangiocarcinoma (ICC) is unclear. We aimed to evaluate the impact of sarcopenia on the prognosis of older patients with ICC undergoing hepatectomy. METHODS: A total of 363 patients with ICC following hepatectomy from 2015 to 2021 were retrospectively reviewed at five institutions. Sarcopenia was evaluated using skeletal muscle index by computed tomography images. Patients were divided into four subgroups according to sarcopenia and age. Postoperative outcomes including complication, overall survival (OS) and recurrence-free survival (RFS) were evaluated. Risk factors were identified through univariate and multivariate Cox regression analyses. RESULTS: 302 patients were included in the analysis. The median age was 63 years and there were 128 patients (42.4%) aged over 65 years. 192 patients (63.6%) were diagnosed with sarcopenia, while 180 patients (59.6%) experienced myosteatosis. Older patients experienced a higher incidence of sarcopenia and myosteatosis, and worse postoperative outcomes than younger patients. In the subgroup of patients with sarcopenia, older patients experienced a significant shorter OS than younger patients, which was not observed in patients without sarcopenia. According to the multivariate Cox regression analysis, lymphatic metastasis (p < .001), blood transfusion (p = .004), low serum albumin (p = .051), sarcopenia (p = .024), and myosteatosis (p = .004) were identified as independent risk factors of OS in older patients, meanwhile tumour size (p = .013) and lymphatic metastasis (p < .001) were independent risk factors of RFS. CONCLUSIONS: Sarcopenia and myosteatosis have a significant adverse impact on postoperative outcomes in older patients with ICC undergoing hepatectomy.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Sarcopenia , Humanos , Anciano , Persona de Mediana Edad , Hepatectomía/efectos adversos , Sarcopenia/complicaciones , Sarcopenia/diagnóstico por imagen , Estudios Retrospectivos , Metástasis Linfática/patología , Colangiocarcinoma/patología , Pronóstico , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/patología
13.
BMC Neurol ; 24(1): 97, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38494491

RESUMEN

OBJECTIVE: To investigate the factors associated with brain frailty and the effect of brain frailty in patients with anterior circulation large artery occlusion (AC-LAO). METHODS: 1100 patients with AC-LVO consecutively admitted to the Second Hospital of Hebei Medical University, North China between June 2016 and April 2018 were retrospectively analyzed. The variables associated with brain frailty and stroke outcome were analyzed by ANOVA analysis, the Mann-Whitney U test and multiple linear regression. Based on previous research. Brain frailty score comprises 1 point each for white matter hyperintensity (WMH), old infarction lesions, and cerebral atrophy among 983 participants with baseline brain magnetic resonance imaging or computed tomography. RESULTS: Among AC-LAO participants, baseline brain frailty score ≥ 1 was common (750/983, 76.3%). Duration of hypertension > 5 years (mean difference [MD] 0.236, 95% CI 0.077, 0.395, p = 0.004), multiple vessel occlusion (MD 0.339, 95% CI 0.068, 0.611, p = 0.014) and basal ganglia infarction (MD -0.308, 95% CI -0.456, -0.160, p < 0.001) were independently associated with brain frailty score. Brain frailty score was independently associated with stroke events, and higher brain frailty scores were associated with higher rates of stroke events (p < 0.001). However, brain frailty has no independent effect on short-term outcome of ACI in AC-LAO patients. CONCLUSIONS: In AC-LAO patients, older age, duration of hypertension > 5 years, and multiple vessel occlusion influenced the brain frailty score. Brain frailty score was independently associated with the occurrence of stroke events in AC-LAO patients.


Asunto(s)
Isquemia Encefálica , Fragilidad , Hipertensión , Accidente Cerebrovascular , Humanos , Estudios Retrospectivos , Fragilidad/complicaciones , Fragilidad/epidemiología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/epidemiología , Encéfalo , Arterias , Infarto
14.
Nucleic Acids Res ; 50(6): e34, 2022 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-34931221

RESUMEN

Identifying rare variants that contribute to complex diseases is challenging because of the low statistical power in current tests comparing cases with controls. Here, we propose a novel and powerful rare variants association test based on the deviation of the observed mutation burden of a gene in cases from a baseline predicted by a weighted recursive truncated negative-binomial regression (RUNNER) on genomic features available from public data. Simulation studies show that RUNNER is substantially more powerful than state-of-the-art rare variant association tests and has reasonable type 1 error rates even for stratified populations or in small samples. Applied to real case-control data, RUNNER recapitulates known genes of Hirschsprung disease and Alzheimer's disease missed by current methods and detects promising new candidate genes for both disorders. In a case-only study, RUNNER successfully detected a known causal gene of amyotrophic lateral sclerosis. The present study provides a powerful and robust method to identify susceptibility genes with rare risk variants for complex diseases.


Asunto(s)
Predisposición Genética a la Enfermedad , Variación Genética , Modelos Genéticos , Programas Informáticos , Estudios de Casos y Controles , Simulación por Computador , Humanos , Mutación
15.
BMC Pediatr ; 24(1): 220, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38561714

RESUMEN

BACKGROUND: Sleep-disordered breathing (SDB) during childhood is common and includes a range of breathing abnormalities that range from primary snoring (PS) to obstructive sleep apnea syndrome (OSAS).Studies have shown that not only OSAS, but also PS, which is originally considered harmless, could cause cardiovascular, cognitive, behavioral, and psychosocial problems. Many researches are focused on the relation of OSA and serum lipid levels. However, little studies are focused on PS and serum lipid levels in children.We evaluated whether serum lipid (total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C),low-density lipoprotein cholesterol (LDL-C)) concentrations were associated with specific components of SDB, including indices of oxygen reduction index, lowest oxygen saturation, mean oxygen saturation. And we explored whether serum lipid levels were associated with different degree sleep disordered (PS and OSA group) and obese. METHODS: This was a cross-sectional study. Children who were complained by their guardians with habitual snoring and(or) mouth breathing were collected in the SDB group. Normal children without sleep problem were matched in the control group. Subjects in the SDB group underwent polysomnography. The serum lipid profiles of all the children included TC, TG, HDL-C and LDL-C concentrations were measured by appropriate enzymatic assays. RESULTS: A total of 241 with Apnea/Hypopnea Index ≥ 5 (AHI) were assigned to the OSAS group and the remaining 155 with normal AHI were assigned to the PS group. The values of TC, TG, LDL-C and LDL/HDL were significantly higher in the OSAS group than in the PS group, and the values in the PS group were significantly higher than the control group. Multiple regression analysis revealed serum TG only correlated negatively with lowest oxygen saturation. Body mass index-z score has a positive effect on TG in all the 1310 children (P = 0.031) and in SDB 396 children(P = 0.012). The level of serum TG in obese group was significantly higher than that in non-obese group. CONCLUSIONS: SDB had a very obvious effect on blood lipids, whereas PS without apnea and hypoxia. Obese only affects the aggregation of TG. TRIAL REGISTRATION: ChiCTR1900026807(2019.10.23).


Asunto(s)
Síndromes de la Apnea del Sueño , Apnea Obstructiva del Sueño , Niño , Humanos , Ronquido , Estudios de Casos y Controles , LDL-Colesterol , Estudios Transversales , Síndromes de la Apnea del Sueño/complicaciones , Apnea Obstructiva del Sueño/complicaciones , Triglicéridos , HDL-Colesterol , Lípidos , Obesidad/complicaciones , Hipoxia/etiología
16.
Sensors (Basel) ; 24(3)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38339661

RESUMEN

Vortex beams carrying orbital angular momentum (OAM) provide a new degree of freedom for light waves in addition to the traditional degrees of freedom, such as intensity, phase, frequency, time, and polarization. Due to the theoretically unlimited orthogonal states, the physical dimension of OAM is capable of addressing the problem of low information capacity. With the advancement of the OAM optical communication technology, OAM router devices (OAM-RDs) have played a key role in significantly improving the flexibility and practicability of communication systems. In this review, major breakthroughs in the OAM-RDs are summarized, and the latest technological standing is examined. Additionally, a detailed account of the recent works published on techniques related to the OAM-RDs has been categorized into five areas: channel multicasting, channel switching, channel filtering, channel hopping, and channel adding/extracting. Meanwhile, the principles, research methods, advantages, and disadvantages are discussed and summarized in depth while analyzing the future development trends and prospects of the OAM-RDs.

17.
Int J Mol Sci ; 25(13)2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-39000292

RESUMEN

Latilactobacillus (L.) sakei is a species of lactic acid bacteria (LAB) mostly studied according to its application in food fermentation. Previously, L. sakei L3 was isolated by our laboratory and possessed the capability of high exopolysaccharide (EPS) yield during sucrose-added fermentation. However, the understanding of sucrose promoting EPS production is still limited. Here, we analyzed the growth characteristics of L. sakei L3 and alterations of its transcriptional profiles during sucrose-added fermentation. The results showed that L. sakei L3 could survive between pH 4.0 and pH 9.0, tolerant to NaCl (<10%, w/v) and urea (<6%, w/v). Meanwhile, transcriptomic analysis showed that a total of 426 differentially expressed genes and eight non-coding RNAs were identified. Genes associated with sucrose metabolism were significantly induced, so L. sakei L3 increased the utilization of sucrose to produce EPS, while genes related to uridine monophosphate (UMP), fatty acids and folate synthetic pathways were significantly inhibited, indicating that L. sakei L3 decreased self-growth, substance and energy metabolism to satisfy EPS production. Overall, transcriptome analysis provided valuable insights into the mechanisms by which L. sakei L3 utilizes sucrose for EPS biosynthesis. The study provided a theoretical foundation for the further application of functional EPS in the food industry.


Asunto(s)
Fermentación , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Latilactobacillus sakei , Polisacáridos Bacterianos , Sacarosa , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/metabolismo , Sacarosa/metabolismo , Latilactobacillus sakei/metabolismo , Latilactobacillus sakei/genética , Transcriptoma , Concentración de Iones de Hidrógeno
18.
Angew Chem Int Ed Engl ; 63(15): e202320037, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38348605

RESUMEN

With the oxygen conversion efficiency of metal-free carbon-based fuel cells dramatically improved, the building blocks of covalent organic frameworks (COFs) raised principal concerns on the catalytic active sites with indistinct electronic states. Herein, to address this issue, we demonstrate COFs for oxygen reduction reaction (ORR) by regulating the edge-hanging thiophene units, and the molecular geometries are further modulated via positional thiophene isomerization strategy, affording isomeric COF-α with 2-substitution and COF-ß with 3-substitution on the frameworks. The electronic states and intermediate adsorption ability are well-regulated through geometric modification, resulting in controllable chemical activity and local density of π-electrons. Notably, the introduction of thiophene units with different substitution positions into a pristine pure carbon-based COF model COF-Ph achieves excellent activity with a half-wave potential of 0.76 V versus the reversible hydrogen electrode, which is higher than most of those metal-free or metal-based electrocatalysts. Utilizing the combination of theoretical prediction and in situ Raman spectra, we show that the isomeric thiophene skeleton (COF-α and COF-ß) can induce the dangling unit activation, accurately identifying the pentacyclic-carbon (thiophene α-position) adjacent to sulfur atom as active sites. The results suggest that the isomeric dangling groups in COFs are suitable for the ORR with promising geometry construction.

19.
J Gene Med ; 25(9): e3530, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37203323

RESUMEN

INTRODUCTION: Colorectal cancer (CRC) is the third most common malignancy and a major cause of cancer-related deaths. Peptidyl arginine deiminase 4 (PAD4 or PADI4) is expressed in neutrophils that, when activated, can drive the formation of neutrophil extracellular traps (NETs). PAD4 has been found to be upregulated in CRC patients and to predict a poor prognosis. This study is aimed at exploring the role of PAD4 inhibitor (GSK484) in NET formation and radioresistance in CRC. METHODS: Reverse transcriptase quantitative polymerase chain reaction and western blotting were used to measure PAD4 expression in CRC tissues and cells. GSK484, an inhibitor of PAD4, was investigated in the following functional assays in vitro: western blotting, clonogenic survival, colony formation, TUNEL, flow cytometry and transwell assays. Nude mouse xenograft models were applied to evaluate the effect of GSK484 on tumor growth in CRC in vivo. The formation of NETs influenced by GSK484 was also investigated. RESULTS: We showed upregulation of PAD4 mRNA and protein in CRC tissues and cells. High expression of PAD4 was related to a poor prognosis in CRC patients. GSK484 treatment promoted the radiosensitivity of CRC cells and induced cell death by promoting DNA double-strand breaks. Rescue experiments further verified that GSK484 inhibited the effects of PAD4 overexpression in irradiated CRC cells. Moreover, GSK484 injection strengthened the radiosensitivity of CRC and inhibited NET formation in vivo. CONCLUSIONS: PAD4 inhibitor GSK484 promotes the radiosensitivity of CRC and inhibits NET formation in vivo and in vitro.


Asunto(s)
Neoplasias Colorrectales , Trampas Extracelulares , Ratones , Animales , Humanos , Trampas Extracelulares/metabolismo , Neutrófilos/metabolismo , Neutrófilos/patología , Tolerancia a Radiación/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/radioterapia , Neoplasias Colorrectales/metabolismo
20.
Small ; 19(17): e2207298, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36703530

RESUMEN

The oxygen reduction reaction (ORR) is a key process in green energy conversion technology. Heteroatom doping has been proven to be a prospective strategy to prepare metal-free carbon-based electrocatalysts, but such methods often suffer from uncontrollable catalyst frameworks and imprecise active sites. Herein, an organic heterocyclic strategy is adopted to modulate the charge redistribution of alkynyl-containing conjugated microporous polymers (CMPs) by introducing varied five-membered heterocyclic structures. Among these CMPs, the S, 2N-containing thiadiazole heterocyclic molecule (CMP-Tdz) with carbonized alginate materials (CCA ) displays a remarkable quasi-four-electron-transfer ORR pathway, exhibiting an excellent half-wave potential (E1/2 ) of 0.77 V, coupled with superior methanol tolerance and electrochemical stability, which are among the highest performance in the metal-free organic catalytic material systems. Density functional theory calculations prove that the high catalytic performance of these catalysts originates from the sp-hybridized C atom (site-2) which is activated by their adjacent heterocyclic structures. Importantly, the five-membered heterocyclic structures can also modulate the local charge distribution, and increase dipole moment, with significantly improved catalytic kinetics. This incorporation of chemically designed heterocyclic-containing alkynyl-CMPs provides a new approach to developing efficient metal-free carbon-based electrocatalysts for fuel cells.

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