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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.
J Cell Mol Med ; 28(18): e18580, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39331689

RESUMEN

Oligo-astheno-teratozoospermia (OAT) is a common cause of male infertility, but the genetic basis of most OAT cases is still unknown. Here, one homozygous loss-of-function (LOF) variant in TDRD6, c.G1825T/p.Gly609X, was identified in an infertile patient with severe OAT by whole-exome sequencing (WES) and Sanger confirmation. Furthermore, Tdrd6-mutant mice (p.Gly615X; equivalent to p.Gly609X in human TDRD6) were generated. Remarkably, the Tdrd6-mutated mice mimicked the severe OAT symptoms of the patient. In addition, the architecture of chromatoid bodies (CBs) were disrupted in round spermatids from Tdrd6-mutant mice, leading to blocked spermatogenesis in the round spermatids. The assembly of PIWIL1, TDRD1, TDRD7 and DDX25 in CBs was disturbed in the Tdrd6-mutant mice. Applying immunoprecipitation-mass spectrometry (IP-MS), we identified some TDRD6-interacting partners, including CB proteins TDRD7, MAEL and PCBP1. Moreover, we described the assisted reproductive technology (ART) outcomes of the infertile patient and his partner. Altogether, our findings provide necessary evidences to support the idea that the homozygous LOF variant in TDRD6 induces male infertility with severe OAT, suggesting that TDRD6 could be a useful genetic diagnostic target for male infertility.


Asunto(s)
Infertilidad Masculina , Masculino , Animales , Humanos , Ratones , Infertilidad Masculina/genética , Infertilidad Masculina/patología , Espermatogénesis/genética , Mutación con Pérdida de Función , Secuenciación del Exoma , Teratozoospermia/genética , Teratozoospermia/patología , Oligospermia/genética , Oligospermia/patología , Astenozoospermia/genética , Astenozoospermia/patología , Modelos Animales de Enfermedad , Homocigoto , Adulto
9.
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
10.
Biochem Biophys Res Commun ; 703: 149665, 2024 04 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
11.
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
12.
J Transl Med ; 22(1): 877, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39350251

RESUMEN

OBJECTIVE: To investigate changes in proportions of peripheral blood lymphocyte subsets, the correlation between the lymphocyte subsets and cytokine levels in patients with GluR3B antibody-positive epilepsy, analyze the role of GluR3B antibodies and cytokines in the progression of epilepsy. In addition, the immunotherapeutic effect in patients with GluR3B antibody-positive epilepsy will be evaluated. METHODS: Patients with epilepsy hospitalized in the Department of Neurology of the affiliated Hospital of Xuzhou Medical University from December 2016 to May 2023 were recruited. GluR3B antibody levels were measured by enzyme-linked immunosorbent assay (ELISA). Lymphocyte subset proportions were determined using flow cytometry, and serum concentrations of 12 cytokines were measured using cytometric beads array. Differences in T lymphocyte subsets and inflammatory factors were analysed between GluR3B antibody positive and negative patients. Structural equation modeling (SEM) was used to analyse the role of GluR3B antibodies and inflammatory factors in drug-resistant epilepsy (DRE). Finally, the therapeutic effect of immunotherapy on epilepsy patients with GluR3B antibodies was assessed. RESULTS: In this study, sixty-four cases of DRE, sixty-six cases of drug-naïve epilepsy (DNE), and forty-one cases of drug-responsive epilepsy were recruited. (1) DRE patients with positive GluR3B antibody were characterized by a significant increase in the proportion of cluster of differentiation (CD)4+ T lymphocytes, a decrease in CD8+ T lymphocytes, and an increase of CD4+/CD8+ ratio. Similar alterations in T lymphocyte subsets were observed in GluR3B antibody-positive patients with DNE. GluR3B antibody levels correlated positively with CD4+ T lymphocytes (r = 0.23) and negatively with CD8+ T lymphocytes (r=-0.18). (2) In patients with DRE, the serum concentrations of interleukin-1ß (IL-1ß), IL-8, and interferon-gamma (IFN-γ) were significantly higher in those with positive GluR3B antibody compared to those with negative GluR3B antibody. Serum IL-1ß levels were also higher in GluR3B antibody-positive DNE patients compared to antibody-negative DNE patients. In drug-responsive epilepsy patients with GluR3B antibody-positive, both serum IL-1ß and IFN-γ levels were higher than those with GluR3B antibody-negative. Moreover, the concentrations of serum GluR3B antibody were positively correlated with the levels of IL-1ß, IL-8, and IFN-γ. (3) SEM analysis indicated that GluR3B antibody may be a direct risk factor for DRE (direct effect = 4.479, 95%CI 0.409-8.503), or may be involved in DRE progression through affecting IFN-γ and IL-8 levels (total indirect effect = 5.101, 95%CI 1.756-8.818). (4) Immunotherapy significantly decreased seizure frequency and serum GluR3B antibody levels, and the seizure frequency was positively correlated with the levels of GluR3B antibody levels in patients receiving immunotherapy. CONCLUSIONS: This study demonstrates that GluR3B antibody may influence the progression of epilepsy through altering the proportion of CD4+ and CD8+ lymphocyte subsets and increasing proinflammatory cytokines. The seizure suppression of immunotherapy is associated with the decrease of GluR3B antibody levels. Thus, the present study contributes to a better understanding of the immunoregulatory mechanisms of autoimmune-associated epilepsy and provides a potential target for DRE.


Asunto(s)
Citocinas , Progresión de la Enfermedad , Epilepsia , Subgrupos de Linfocitos T , Humanos , Masculino , Femenino , Epilepsia/inmunología , Epilepsia/sangre , Adulto , Citocinas/sangre , Subgrupos de Linfocitos T/inmunología , Receptores AMPA/inmunología , Adulto Joven , Mediadores de Inflamación/sangre , Mediadores de Inflamación/metabolismo , Persona de Mediana Edad , Adolescente , Autoanticuerpos/sangre , Autoanticuerpos/inmunología , Inflamación/sangre , Inflamación/inmunología
13.
J Hum Genet ; 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39155345

RESUMEN

Male infertility is a widespread population health concern, causing various degrees of adverse fertility outcomes. We determined the genetic cause of an infertile male from a consanguineous family, expanding the mutant spectrum of male infertility. A non-obstructive azoospermia (NOA) patient was recruited, and histological type of human testicular tissue of the patient categorized as maturation arrest. We identified a novel loss-of-function variant of syntaxin 2 (STX2) (c.142C>T:p.Gln48*) by performing Whole-exome sequencing (WES) on the NOA patient from a consanguineous Chinese family. Sanger sequencing confirmed the p.Gln48* variant was maternally and paternally inherited. The variant was predicted to be deleterious and resulted in aberrant changes to structure and function of STX2 by In silico analysis. In summary, we reported for the first time that a nonsense variant occurred in the exon region of STX2 in an infertile male presenting with NOA, which was beneficial for diagnosis and therapies of NOA.

14.
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.

15.
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
16.
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
17.
BMC Cardiovasc Disord ; 24(1): 430, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39148039

RESUMEN

BACKGROUND: Both atrial fibrillation (AF) and heart failure (HF) are common cardiovascular diseases. If the two exist together, the risk of stroke, hospitalization for HF and all-cause death is increased. Currently, research on left atrial appendage closure (LAAC) in patients with AF and HF is limited and controversial. This study was designed to investigate the safety and effectiveness of LAAC in AF patients with different types of HF. METHODS: Patients with non-valvular atrial fibrillation (NVAF) and HF who underwent LAAC in the First Affiliated Hospital of Army Medical University from August 2014 to July 2021 were enrolled. According to left ventricular ejection fraction (LVEF), the study divided into HF with reduced ejection fraction (LVEF < 50%, HFrEF) group and HF with preserved ejection fraction (LVEF ≥ 50%, HFpEF) group. The data we collected from patients included: gender, age, comorbid diseases, CHA2DS2-VASc score, HAS-BLED score, NT-proBNP level, residual shunt, cardiac catheterization results, occluder size, postoperative medication regimen, transthoracic echocardiography (TTE) results and transesophageal echocardiography (TEE) results, etc. Patients were followed up for stroke, bleeding, device related thrombus (DRT), pericardial tamponade, hospitalization for HF, and all-cause death within 2 years after surgery. Statistical methods were used to compare the differences in clinical outcome of LAAC in AF patients with different types of HF. RESULTS: Overall, 288 NVAF patients with HF were enrolled in this study, including 142 males and 146 females. There were 74 patients in the HFrEF group and 214 patients in the HFpEF group. All patients successfully underwent LAAC. The CHA2DS2-VASc score and HAS-BLED score of HFrEF group were lower than those of HFpEF group. A total of 288 LAAC devices were implanted. The average diameter of the occluders was 27.2 ± 3.5 mm in the HFrEF group and 26.8 ± 3.3 mm in the HFpEF group, and there was no statistical difference between the two groups (P = 0.470). Also, there was no statistically significant difference in the occurrence of residual shunts between the two groups as detected by TEE after surgery (P = 0.341). LVEF was significantly higher in HFrEF group at 3 days, 3 months and 1 year after operation than before (P < 0.001). At 45-60 days after surgery, we found DRT in 9 patients and there were 4 patients (5.4%) in HFrEF group and 5 patients (2.3%) in HFpEF group, with no significant difference between the two groups (P = 0.357). One patient with DRT had stroke. The incidence of stroke was 11.1% in patients with DRT and 0.7% in patients without DRT (P = 0.670). There was one case of postoperative pericardial tamponade, which was improved by pericardiocentesis at 24 h after surgery in the HFpEF group, and there was no significant difference between the two groups (P = 1.000). During a mean follow-up period of 49.7 ± 22.4 months, there were no significant differences in the incidence of stroke, bleeding, DRT and HF exacerbation between the two groups. We found a statistical difference in the improvement of HF between HFrEF group and HFpEF group (P < 0.05). CONCLUSIONS: LAAC is safe and effective in AF patients with different types of HF. The improvement of cardiac function after LAAC is more pronounced in HFrEF group than in HFpEF group.


Asunto(s)
Fibrilación Atrial , Función del Atrio Izquierdo , Insuficiencia Cardíaca , Cierre del Apéndice Auricular Izquierdo , Accidente Cerebrovascular , Función Ventricular Izquierda , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Apéndice Atrial/diagnóstico por imagen , Apéndice Atrial/fisiopatología , Apéndice Atrial/cirugía , Fibrilación Atrial/complicaciones , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Fibrilación Atrial/cirugía , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/cirugía , Cierre del Apéndice Auricular Izquierdo/efectos adversos , Recuperación de la Función , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Volumen Sistólico , Factores de Tiempo , Resultado del Tratamiento
18.
Biofouling ; 40(9): 617-631, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39291398

RESUMEN

The impact of Flavin adenine dinucleotide (FAD) on sulfate-reducing bacteria (SRB) corrosion of a pipeline welded joint (WJ) was investigated under anaerobic condition in this paper. The results showed that the thickness of the corrosion product on heat affected zone (HAZ) was lower than that on base metal (BM) and welded zone (WZ), and the FAD addition enhanced the development of the protruding microbial tubercles on the WJ. The local corrosion degrees of the BM and WZ coupons were significantly higher than that of the HAZ coupon. Besides, the FAD addition simultaneously promoted local corrosion of all three zones of the WJ in the SRB inoculated environment, and the promotion role was much more pronounced on the WZ coupons. The selective promotion effect of FAD on SRB corrosion in the WJ was attributed to the special structure of the WZ, the selected SRB attachment and the FAD/FADH2 redox feedback cycle.


Asunto(s)
Desulfovibrio desulfuricans , Flavina-Adenina Dinucleótido , Corrosión , Flavina-Adenina Dinucleótido/metabolismo , Flavina-Adenina Dinucleótido/química , Desulfovibrio desulfuricans/metabolismo , Oxidación-Reducción , Biopelículas
19.
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
20.
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
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