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1.
Immunity ; 54(7): 1611-1621.e5, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-34166623

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants continue to emerge during the global pandemic and may facilitate escape from current antibody therapies and vaccine protection. Here we showed that the South African variant B.1.351 was the most resistant to current monoclonal antibodies and convalescent plasma from coronavirus disease 2019 (COVID-19)-infected individuals, followed by the Brazilian variant P.1 and the United Kingdom variant B.1.1.7. This resistance hierarchy corresponded with Y144del and 242-244del mutations in the N-terminal domain and K417N/T, E484K, and N501Y mutations in the receptor-binding domain (RBD) of SARS-CoV-2. Crystal structure analysis of the B.1.351 triple mutant (417N-484K-501Y) RBD complexed with the monoclonal antibody P2C-1F11 revealed the molecular basis for antibody neutralization and escape. B.1.351 and P.1 also acquired the ability to use mouse and mink ACE2 receptors for entry. Our results demonstrate major antigenic shifts and potential broadening of the host range for B.1.351 and P.1 variants, which poses serious challenges to current antibody therapies and vaccine protection.


Asunto(s)
Enzima Convertidora de Angiotensina 2/metabolismo , Anticuerpos Neutralizantes/inmunología , Evasión Inmune , SARS-CoV-2/inmunología , Animales , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Anticuerpos Neutralizantes/química , Variación Antigénica/genética , COVID-19/inmunología , COVID-19/virología , Especificidad del Huésped , Humanos , Evasión Inmune/genética , Ratones , Visón , Mutación , Unión Proteica , SARS-CoV-2/genética , SARS-CoV-2/fisiología , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Glicoproteína de la Espiga del Coronavirus/metabolismo , Internalización del Virus
2.
Plant J ; 118(5): 1550-1568, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38412303

RESUMEN

The increased soil salinity is becoming a major challenge to produce more crops and feed the growing population of the world. In this study, we demonstrated that overexpression of OsDIR55 gene enhances rice salt tolerance by altering the root diffusion barrier. OsDIR55 is broadly expressed in all examined tissues and organs with the maximum expression levels at lignified regions in rice roots. Salt stress upregulates the expression of OsDIR55 gene in an abscisic acid (ABA)-dependent manner. Loss-function and overexpression of OsDIR55 compromised and improved the development of CS and root diffusion barrier, manifested with the decreased and increased width of CS, respectively, and ultimately affected the permeability of the apoplastic diffusion barrier in roots. OsDIR55 deficiency resulted in Na+ accumulation, ionic imbalance, and growth arrest, whereas overexpression of OsDIR55 enhances salinity tolerance and provides an overall benefit to plant growth and yield potential. Collectively, we propose that OsDIR55 is crucial for ions balance control and salt stress tolerance through regulating lignification-mediated root barrier modifications in rice.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Oryza , Proteínas de Plantas , Raíces de Plantas , Tolerancia a la Sal , Oryza/genética , Oryza/fisiología , Oryza/metabolismo , Oryza/crecimiento & desarrollo , Raíces de Plantas/genética , Raíces de Plantas/fisiología , Raíces de Plantas/crecimiento & desarrollo , Raíces de Plantas/metabolismo , Tolerancia a la Sal/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Abscísico/metabolismo , Sodio/metabolismo , Plantas Modificadas Genéticamente , Estrés Salino/genética
3.
Bioinformatics ; 40(5)2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38613848

RESUMEN

MOTIVATION: Identifying chromatin accessibility is one of the key steps in studying the regulation of eukaryotic genomes. The combination of exogenous methyltransferase and nanopore sequencing provides an strategy to identify open chromatin over long genomic ranges at the single-molecule scale. However, endogenous methylation, non-open-chromatin-specific exogenous methylation and base-calling errors limit the accuracy and hinders its application to complex genomes. RESULTS: We systematically evaluated the impact of these three influence factors, and developed a model-based computational method, methyltransferase accessible genome region finder (MAGNIFIER), to address the issues. By incorporating control data, MAGNIFIER attenuates the three influence factors with data-adaptive comparison strategy. We demonstrate that MAGNIFIER is not only sensitive to identify the open chromatin with much improved accuracy, but also able to detect the chromatin accessibility of repetitive regions that are missed by NGS-based methods. By incorporating long-read RNA-seq data, we revealed the association between the accessible Alu elements and non-classic gene isoforms. AVAILABILITY AND IMPLEMENTATION: Freely available on web at https://github.com/Goatofmountain/MAGNIFIER.


Asunto(s)
Cromatina , Genoma Humano , Secuenciación de Nanoporos , Humanos , Cromatina/metabolismo , Cromatina/química , Secuenciación de Nanoporos/métodos , Metiltransferasas/metabolismo , Metilación de ADN
4.
Nature ; 565(7737): 49-55, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30479383

RESUMEN

The proteasome is an ATP-dependent, 2.5-megadalton molecular machine that is responsible for selective protein degradation in eukaryotic cells. Here we present cryo-electron microscopy structures of the substrate-engaged human proteasome in seven conformational states at 2.8-3.6 Å resolution, captured during breakdown of a polyubiquitylated protein. These structures illuminate a spatiotemporal continuum of dynamic substrate-proteasome interactions from ubiquitin recognition to substrate translocation, during which ATP hydrolysis sequentially navigates through all six ATPases. There are three principal modes of coordinated hydrolysis, featuring hydrolytic events in two oppositely positioned ATPases, in two adjacent ATPases and in one ATPase at a time. These hydrolytic modes regulate deubiquitylation, initiation of translocation and processive unfolding of substrates, respectively. Hydrolysis of ATP powers a hinge-like motion in each ATPase that regulates its substrate interaction. Synchronization of ATP binding, ADP release and ATP hydrolysis in three adjacent ATPases drives rigid-body rotations of substrate-bound ATPases that are propagated unidirectionally in the ATPase ring and unfold the substrate.


Asunto(s)
Microscopía por Crioelectrón , Complejo de la Endopetidasa Proteasomal/metabolismo , Complejo de la Endopetidasa Proteasomal/ultraestructura , Adenosina Trifosfatasas/metabolismo , Adenosina Trifosfato/metabolismo , Regulación Alostérica , Holoenzimas/química , Holoenzimas/metabolismo , Holoenzimas/ultraestructura , Humanos , Hidrólisis , Modelos Moleculares , Complejo de la Endopetidasa Proteasomal/química , Conformación Proteica , Estructura Cuaternaria de Proteína , Desplegamiento Proteico , Especificidad por Sustrato , Ubiquitinación
5.
Nature ; 574(7780): 722-725, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31645759

RESUMEN

The enzyme protochlorophyllide oxidoreductase (POR) catalyses a light-dependent step in chlorophyll biosynthesis that is essential to photosynthesis and, ultimately, all life on Earth1-3. POR, which is one of three known light-dependent enzymes4,5, catalyses reduction of the photosensitizer and substrate protochlorophyllide to form the pigment chlorophyllide. Despite its biological importance, the structural basis for POR photocatalysis has remained unknown. Here we report crystal structures of cyanobacterial PORs from Thermosynechococcus elongatus and Synechocystis sp. in their free forms, and in complex with the nicotinamide coenzyme. Our structural models and simulations of the ternary protochlorophyllide-NADPH-POR complex identify multiple interactions in the POR active site that are important for protochlorophyllide binding, photosensitization and photochemical conversion to chlorophyllide. We demonstrate the importance of active-site architecture and protochlorophyllide structure in driving POR photochemistry in experiments using POR variants and protochlorophyllide analogues. These studies reveal how the POR active site facilitates light-driven reduction of protochlorophyllide by localized hydride transfer from NADPH and long-range proton transfer along structurally defined proton-transfer pathways.


Asunto(s)
Clorofila/biosíntesis , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/química , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Synechococcus/enzimología , Synechocystis/enzimología , Catálisis , Clorofila/química , Estructura Molecular , Fotoquímica , Protoclorofilida/metabolismo , Relación Estructura-Actividad , Especificidad por Sustrato
6.
Nucleic Acids Res ; 51(21): 11634-11651, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37870468

RESUMEN

Bromodomain-containing protein 9 (BRD9) is a specific subunit of the non-canonical SWI/SNF (ncBAF) chromatin-remodeling complex, whose function in human embryonic stem cells (hESCs) remains unclear. Here, we demonstrate that impaired BRD9 function reduces the self-renewal capacity of hESCs and alters their differentiation potential. Specifically, BRD9 depletion inhibits meso-endoderm differentiation while promoting neural ectoderm differentiation. Notably, supplementation of NODAL, TGF-ß, Activin A or WNT3A rescues the differentiation defects caused by BRD9 loss. Mechanistically, BRD9 forms a complex with BRD4, SMAD2/3, ß-CATENIN and P300, which regulates the expression of pluripotency genes and the activity of TGF-ß/Nodal/Activin and Wnt signaling pathways. This is achieved by regulating the deposition of H3K27ac on associated genes, thus maintaining and directing hESC differentiation. BRD9-mediated regulation of the TGF-ß/Activin/Nodal pathway is also demonstrated in the development of pancreatic and breast cancer cells. In summary, our study highlights the crucial role of BRD9 in the regulation of hESC self-renewal and differentiation, as well as its participation in the progression of pancreatic and breast cancers.


Asunto(s)
Células Madre Embrionarias Humanas , Neoplasias , Humanos , Factor de Crecimiento Transformador beta/genética , Células Madre Embrionarias Humanas/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Células Madre Embrionarias/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Diferenciación Celular/genética , Activinas/metabolismo , Vía de Señalización Wnt , Neoplasias/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo
7.
Nano Lett ; 24(25): 7572-7577, 2024 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-38860969

RESUMEN

Achieving high-temperature superlubricity is essential for modern extreme tribosystems. Solid lubrication is the sole viable alternative due to the degradation of liquid ones but currently suffers from notable wear, instability, and high friction coefficient. Here, we report robust superlubricity in MoS2/graphene van der Waals heterostructures at high temperatures up to ∼850 K, achieved through localized heating to enable reliable friction testing. The ultralow friction of the MoS2/graphene heterostructure is found to be notably further reduced at elevated temperature and dominantly contributed by the MoS2 edge. The observation can be well described by a multi-contact model, wherein the thermally activated rupture of edge-contacts facilitates the sliding. Our results should be applicable to other van der Waals heterostructures and shed light on their applications for superlubricity at elevated temperature.

8.
J Biol Chem ; 299(3): 102953, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36731795

RESUMEN

Acid-sensing ion channels (ASICs) play an important role in pain associated with tissue acidification. Peripheral inhibitory group II metabotropic glutamate receptors (mGluRs) have analgesic effects in a variety of pain conditions. Whether there is a link between ASICs and mGluRs in pain processes is still unclear. Herein, we show that the group II mGluR agonist LY354740 inhibited acid-evoked ASIC currents and action potentials in rat dorsal root ganglia neurons. LY354740 reduced the maximum current response to protons, but it did not change the sensitivity of ASICs to protons. LY354740 inhibited ASIC currents by activating group II mGluRs. We found that the inhibitory effect of LY354740 was blocked by intracellular application of the Gi/o protein inhibitor pertussis toxin and the cAMP analogue 8-Br-cAMP and mimicked by the protein kinase A (PKA) inhibitor H-89. LY354740 also inhibited ASIC3 currents in CHO cells coexpressing mGluR2 and ASIC3 but not in cells expressing ASIC3 alone. In addition, intraplantar injection of LY354740 dose-dependently alleviated acid-induced nociceptive behavior in rats through local group II mGluRs. Together, these results suggested that activation of peripheral group II mGluRs inhibited the functional activity of ASICs through a mechanism that depended on Gi/o proteins and the intracellular cAMP/PKA signaling pathway in rat dorsal root ganglia neurons. We propose that peripheral group II mGluRs are an important therapeutic target for ASIC-mediated pain.


Asunto(s)
Canales Iónicos Sensibles al Ácido , Ganglios Espinales , Receptores de Glutamato Metabotrópico , Células Receptoras Sensoriales , Animales , Cricetinae , Ratas , Canales Iónicos Sensibles al Ácido/metabolismo , Cricetulus , Ganglios Espinales/metabolismo , Dolor , Protones , Ratas Sprague-Dawley , Receptores de Glutamato Metabotrópico/metabolismo , Células Receptoras Sensoriales/metabolismo , Potenciales de Acción , Células CHO
9.
J Am Chem Soc ; 146(12): 8780-8786, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38497732

RESUMEN

The small RNAs on living cell membranes were recently found to be N-glycosylated and terminated with sialic acids, although the glycosylation sites and potential functions remain unclear. Herein, we designed a second-generation hierarchical coding strategy (HieCo 2) for in situ visualization of cell surface RNA-specific sialylation. After covalently binding DNA codes to sialic acids and then binding a DNA code to a target RNA via sequence specificity, cascade decoding processes were performed with subsequent signal amplification that enabled sensitive in situ visualization of low-abundance Y5 RNA-specific sialic acids on living cell membranes. The proposed strategy unveils the number of glycosylation sites on a single RNA and reveals the binding preference of glycosylated RNAs to different sialic acid binding-immunoglobulin lectin-type receptors, demonstrating a new route for exploration of the glycosylated RNA-related biological and pathological processes.


Asunto(s)
ARN , Ácidos Siálicos , Glicosilación , ARN/metabolismo , Membrana Celular/metabolismo , Ácidos Siálicos/metabolismo , ADN/metabolismo , Ácido N-Acetilneuramínico/metabolismo
10.
Am J Physiol Gastrointest Liver Physiol ; 326(6): G697-G711, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38591127

RESUMEN

Sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP) is a widely expressed membrane glycoprotein that acts as an important modulator of lipid metabolism and inflammatory stress. N-glycosylation of SCAP has been suggested to modulate cancer development, but its role in nonalcoholic steatohepatitis (NASH) is poorly understood. In this study, the N-glycosylation of SCAP was analyzed by using sequential trypsin proteolysis and glycosidase treatment. The liver cell lines expressing wild-type and N-glycosylation sites mutated SCAP were constructed to investigate the N-glycosylation role of SCAP in regulating inflammation and lipid accumulation as well as the underlying mechanisms. The hepatic SCAP protein levels were significantly increased in C57BL/6J mice fed with Western diet and sugar water (WD + SW) and diabetic db/db mice, which exhibited typical liver steatosis and inflammation accompanied with hyperglycemia. In vitro, the enhanced N-glycosylation by high glucose increased the protein stability of SCAP and hence increased its total protein levels, whereas the ablation of N-glycosylation significantly decreased SCAP protein stability and alleviated lipid accumulation and inflammation in hepatic cell lines. Mechanistically, SCAP N-glycosylation increased not only the SREBP-1-mediated acetyl-CoA synthetase 2 (ACSS2) transcription but also the AMPK-mediated S659 phosphorylation of ACCS2 protein, causing the enhanced ACSS2 levels in nucleus and hence increasing the histone H3K27 acetylation (H3K27ac), which is a key epigenetic modification associated with NASH. Modulating ACSS2 expression or its location in the nuclear abolished the effects of SCAP N-glycosylation on H3K27ac and lipid accumulation and inflammation. In conclusion, SCAP N-glycosylation aggravates inflammation and lipid accumulation through enhancing ACSS2-mediated H3K27ac in hepatocytes.NEW & NOTEWORTHY N-glycosylation of SCAP exacerbates inflammation and lipid accumulation in hepatocytes through ACSS2-mediated H3K27ac. Our data suggest that SCAP N-glycosylation plays a key role in regulating histone H3K27 acetylation and targeting SCAP N-glycosylation may be a new strategy for treating nonalcoholic steatohepatitis (NASH).


Asunto(s)
Histonas , Péptidos y Proteínas de Señalización Intracelular , Metabolismo de los Lípidos , Proteínas de la Membrana , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico , Animales , Glicosilación , Histonas/metabolismo , Acetilación , Ratones , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Metabolismo de los Lípidos/fisiología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Enfermedad del Hígado Graso no Alcohólico/patología , Masculino , Humanos , Hígado/metabolismo , Hígado/patología
11.
Pharmacogenomics J ; 24(2): 8, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38485921

RESUMEN

BACKGROUND: Tibetan medicine Gaoyuan'an capsule (GYAC) is widely used to prevent pulmonary edema at high altitude, but the specific mechanism has not been explored. In this study, we analyzed the mechanism of GYAC in hypoxia tolerance, and provided a new idea for the prevention and treatment of altitude disease. METHODS: The effective components and corresponding targets of GYAC were screened out by the Chinese herbal medicine network database, and the key targets of hypoxia tolerance were retrieved by Genecards, OMIM and PubMed database. Cytoscape 3.7.2 was used to construct GYAC ingredient-target-hypoxia tolerance-related target network. GO function annotation and KEGG enrichment analysis were performed to predict the pathways in which target genes may be involved, and molecular docking was used to verify the binding ability of the compound to target genes. In vitro, the above results were further verified by molecular experiment. RESULTS: We found that GYAC can improve hypoxia tolerance by regulating various target genes, including IL6, IFNG, etc. The main regulatory pathways were HIF-1 signaling pathway. Molecular docking showed that the affinity between luteolin and target genes (IL6, IFNG) were better. In vitro, we observed that hypoxia can inhibit cell viability and promote apoptosis of H9C2 cell. And hypoxia can promote the expression of LDH. After the addition of luteolin, the decrease of cell viability, the increase of cell apoptosis, LDH release and the decrease of mitochondrial membrane potential were inhibited. Besides, inflammatory related factors (IL-6, IL-10, IL-2, IFNG and VEGFA) expression were also inhibited hypoxic cell models. CONCLUSIONS: The results of network pharmacology and molecular docking showed that luteolin, a monomeric component of GYAC, played a role in hypoxia tolerance through a variety of target genes, such as IL6, IFNG. What's more, we have discovered that luteolin can reduce the inflammatory response in cardiac myocytes, thereby alleviating mitochondrial damage, and ultimately enhancing the hypoxia tolerance of H9C2 cardiomyocytes.


Asunto(s)
Medicamentos Herbarios Chinos , Interleucina-6 , Humanos , Simulación del Acoplamiento Molecular , Luteolina , Farmacología en Red , Hipoxia/tratamiento farmacológico , Hipoxia/genética , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico
12.
J Med Virol ; 96(2): e29445, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38299743

RESUMEN

Membrane-associated RING-CH (MARCH) family proteins were recently reported to inhibit viral replication through multiple modes. Previous work showed that human MARCH8 blocked Ebola virus (EBOV) glycoprotein (GP) maturation. Our study here demonstrates that human MARCH1 and MARCH2 share a similar pattern to MARCH8 in restricting EBOV GP-pseudotyped viral infection. Human MARCH1 and MARCH2 retain EBOV GP at the trans-Golgi network, reduce its cell surface display, and impair EBOV GP-pseudotyped virions infectivity. Furthermore, we uncover that the host proprotein convertase furin could interact with human MARCH1/2 and EBOV GP intracellularly. Importantly, the furin P domain is verified to be recognized by MARCH1/2/8, which is critical for their blocking activities. Besides, bovine MARCH2 and murine MARCH1 also impair EBOV GP proteolytic processing. Altogether, our findings confirm that MARCH1/2 proteins of different mammalian origins showed a relatively conserved feature in blocking EBOV GP cleavage, which could provide clues for subsequent MARCHs antiviral studies and may facilitate the development of novel strategies to antagonize enveloped virus infection.


Asunto(s)
Ebolavirus , Fiebre Hemorrágica Ebola , Animales , Bovinos , Humanos , Ratones , Línea Celular , Furina/metabolismo , Glicoproteínas , Mamíferos/metabolismo , Proteínas de la Membrana/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Envoltura Viral/metabolismo , Proteínas del Envoltorio Viral/genética , Proteínas del Envoltorio Viral/metabolismo
13.
Metabolomics ; 20(3): 57, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38773045

RESUMEN

BACKGROUND: Despite the clear clinical diagnostic criteria for necrozoospermia in andrology, the fundamental mechanisms underlying it remain elusive. This study aims to profile the lipid composition in seminal plasma systematically and to ascertain the potential of lipid biomarkers in the accurate diagnosis of necrozoospermia. It also evaluates the efficacy of a lipidomics-based random forest algorithm model in identifying necrozoospermia. METHODS: Seminal plasma samples were collected from patients diagnosed with necrozoospermia (n = 28) and normozoospermia (n = 28). Liquid chromatography-mass spectrometry (LC-MS) was used to perform lipidomic analysis and identify the underlying biomarkers. A lipid functional enrichment analysis was conducted using the LION lipid ontology database. The top 100 differentially significant lipids were subjected to lipid biomarker examination through random forest machine learning model. RESULTS: Lipidomic analysis identified 46 lipid classes comprising 1267 lipid metabolites in seminal plasma. The top five enriched lipid functions as follows: fatty acid (FA) with ≤ 18 carbons, FA with 16-18 carbons, monounsaturated FA, FA with 18 carbons, and FA with 16 carbons. The top 100 differentially significant lipids were subjected to machine learning analysis and identified 20 feature lipids. The random forest model identified lipids with an area under the curve > 0.8, including LPE(20:4) and TG(4:0_14:1_16:0). CONCLUSIONS: LPE(20:4) and TG(4:0_14:1_16:0), were identified as differential lipids for necrozoospermia. Seminal plasma lipidomic analysis could provide valuable biochemical information for the diagnosis of necrozoospermia, and its combination with conventional sperm analysis may improve the accuracy and reliability of the diagnosis.


Asunto(s)
Algoritmos , Lipidómica , Semen , Masculino , Humanos , Semen/metabolismo , Semen/química , Lipidómica/métodos , Adulto , Lípidos/análisis , Lípidos/sangre , Biomarcadores/sangre , Aprendizaje Automático , Cromatografía Liquida/métodos , Infertilidad Masculina/diagnóstico , Infertilidad Masculina/metabolismo , Espectrometría de Masas/métodos , Bosques Aleatorios
14.
Cancer Invest ; : 1-11, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38965994

RESUMEN

Despite the emergence of various treatment strategies for rectal cancer based on neoadjuvant chemoradiotherapy, there is currently a lack of reliable biomarkers to determine which patients will respond well to neoadjuvant chemoradiotherapy. Through collecting hematological and biochemical parameters data of patients prior to receiving neoadjuvant chemoradiotherapy, we evaluated the predictive value of systemic inflammatory indices for pathological response and prognosis in rectal cancer patients. We found that baseline GRIm-Score was an independent predictor for MPR in rectal cancer patients. However, no association was observed between several commonly systemic inflammation indices and long-term outcome.

15.
Psychol Med ; 54(3): 582-591, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37553976

RESUMEN

BACKGROUND: The age-related heterogeneity in major depressive disorder (MDD) has received significant attention. However, the neural mechanisms underlying such heterogeneity still need further investigation. This study aimed to explore the common and distinct functional brain abnormalities across different age groups of MDD patients from a large-sample, multicenter analysis. METHODS: The analyzed sample consisted of a total of 1238 individuals including 617 MDD patients (108 adolescents, 12-17 years old; 411 early-middle adults, 18-54 years old; and 98 late adults, > = 55 years old) and 621 demographically matched healthy controls (60 adolescents, 449 early-middle adults, and 112 late adults). MDD-related abnormalities in brain functional connectivity (FC) patterns were investigated in each age group separately and using the whole pooled sample, respectively. RESULTS: We found shared FC reductions among the sensorimotor, visual, and auditory networks across all three age groups of MDD patients. Furthermore, adolescent patients uniquely exhibited increased sensorimotor-subcortical FC; early-middle adult patients uniquely exhibited decreased visual-subcortical FC; and late adult patients uniquely exhibited wide FC reductions within the subcortical, default-mode, cingulo-opercular, and attention networks. Analysis of covariance models using the whole pooled sample further revealed: (1) significant main effects of age group on FCs within most brain networks, suggesting that they are decreased with aging; and (2) a significant age group × MDD diagnosis interaction on FC within the default-mode network, which may be reflective of an accelerated aging-related decline in default-mode FCs. CONCLUSIONS: To summarize, these findings may deepen our understanding of the age-related biological and clinical heterogeneity in MDD.


Asunto(s)
Trastorno Depresivo Mayor , Adulto , Humanos , Adolescente , Niño , Adulto Joven , Persona de Mediana Edad , Imagen por Resonancia Magnética , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Corteza Insular
16.
Neurochem Res ; 49(5): 1254-1267, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38381246

RESUMEN

Fibrotic scars play important roles in tissue reconstruction and functional recovery in the late stage of nervous system injury. However, the mechanisms underlying fibrotic scar formation and regulation remain unclear. Casein kinase II (CK2) is a protein kinase that regulates a variety of cellular functions through the phosphorylation of proteins, including bromodomain-containing protein 4 (BRD4). CK2 and BRD4 participate in fibrosis formation in a variety of tissues. However, whether CK2 affects fibrotic scar formation remains unclear, as do the mechanisms of signal regulation after cerebral ischemic injury. In this study, we assessed whether CK2 could modulate fibrotic scar formation after cerebral ischemic injury through BRD4. Primary meningeal fibroblasts were isolated from neonatal rats and treated with transforming growth factor-ß1 (TGF-ß1), SB431542 (a TGF-ß1 receptor kinase inhibitor) or TBB (a highly potent CK2 inhibitor). Adult SD rats were intraperitoneally injected with TBB to inhibit CK2 after MCAO/R. We found that CK2 expression was increased in vitro in the TGF-ß1-induced fibrosis model and in vivo in the MCAO/R injury model. The TGF-ß1 receptor kinase inhibitor SB431542 decreased CK2 expression in fibroblasts. The CK2 inhibitor TBB reduced the increases in proliferation, migration and activation of fibroblasts caused by TGF-ß1 in vitro, and it inhibited fibrotic scar formation, ameliorated histopathological damage, protected Nissl bodies, decreased infarct volume and alleviated neurological deficits after MCAO/R injury in vivo. Furthermore, CK2 inhibition decreased BRD4 phosphorylation both in vitro and in vivo. The findings of the present study suggested that CK2 may control BRD4 phosphorylation to regulate fibrotic scar formation, to affecting outcomes after ischemic stroke.


Asunto(s)
Benzamidas , Proteínas que Contienen Bromodominio , Quinasa de la Caseína II , Cicatriz , Dioxoles , Accidente Cerebrovascular Isquémico , Animales , Ratas , Quinasa de la Caseína II/antagonistas & inhibidores , Quinasa de la Caseína II/metabolismo , Cicatriz/metabolismo , Cicatriz/patología , Fibroblastos/metabolismo , Fibrosis , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/metabolismo , Proteínas Nucleares , Fosforilación , Ratas Sprague-Dawley , Factores de Transcripción/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , Proteínas que Contienen Bromodominio/efectos de los fármacos , Proteínas que Contienen Bromodominio/metabolismo
17.
J Surg Res ; 296: 18-28, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38215673

RESUMEN

INTRODUCTION: Ventricular septal defect (VSD) is the most common congenital heart malformation in children. This study aimed to investigate potential pathogenic genes associated with Tibetan familial VSD. METHODS: Whole genomic DNA was extracted from eight Tibetan children with VSD and their healthy parents (a total of 16 individuals). Whole-exome sequencing was performed using the Illumina HiSeq platform. After filtration, detection, and annotation, single nucleotide variations and insertion-deletion markers were examined. Comparative evaluations using the Sorting Intolerant from Tolerant, PolyPhen V2, Mutation Taster, and Combined Annotation Dependent Depletion databases were conducted to predict harmful mutant genes associated with the etiology of Tibetan familial VSD. RESULTS: A total of six missense mutations in genetic disease-causing genes associated with the development of Tibetan familial VSD were identified: activin A receptor type II-like 1 (c.652 C > T: p.R218 W), ATPase cation transporting 13A2 (c.1363 C > T: p.R455 W), endoplasmic reticulum aminopeptidase 1 (c.481 G > A: p.G161 R), MRI1 (c.629 G > A: p.R210Q), tumor necrosis factor receptor-associated protein 1 (c.224 G > A: p.R75H), and FBN2 (c.2260 G > A: p.G754S). The Human Gene Mutation Database confirmed activin A receptor type II-like 1, MRI1, and tumor necrosis factor receptor-associated protein 1 as pathogenic mutations, while FBN2 was classified as a probable pathogenic mutation. CONCLUSIONS: This novel study directly screens genetic variations associated with Tibetan familial VSD using whole-exome sequencing, providing new insights into the pathogenesis of VSD.


Asunto(s)
Cardiopatías Congénitas , Defectos del Tabique Interventricular , Niño , Humanos , Secuenciación del Exoma , Tibet , Defectos del Tabique Interventricular/genética , Defectos del Tabique Interventricular/metabolismo , Receptores del Factor de Necrosis Tumoral/genética
18.
Nanotechnology ; 35(12)2024 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-38100843

RESUMEN

Mucosal delivery systems have gained much attention as effective way for antigen delivery that induces both systemic and mucosal immunity. However, mucosal vaccination faces the challenges of mucus barrier and effective antigen uptake and presentation. In particular, split, subunit and recombinant protein vaccines that do not have an intact pathogen structure lack the efficiency to stimulate mucosal immunity. In this study, poly (lactic acid-co-glycolic acid-polyethylene glycol) (PLGA-PEG) block copolymers were modified by mannose to form a PLGA-PEG-Man conjugate (mannose modified PLGA-PEG), which were characterized. The novel nanoparticles (NPs) prepared with this material had a particle size of about 150 nm and a zeta potential of -15 mV, and possessed ideal mucus permeability, immune cell targeting, stability and low toxicity. Finally, PLGA-PEG-Man nanoparticles (PLGA-PEG-Man NPs) were successfully applied for intranasal delivery of split influenza vaccine in rat for the first time, which triggered strong systemic and mucosal immune responses. These studies suggest that PLGA-PEG-Man NPs could function as competitive potential nano-adjuvants to address the challenge of inefficient mucosal delivery of non-allopathogenic antigens.


Asunto(s)
Vacunas contra la Influenza , Nanopartículas , Humanos , Ratas , Animales , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Ácido Poliglicólico/química , Ácido Láctico/química , Manosa , Adyuvantes Inmunológicos/farmacología , Antígenos , Nanopartículas/química
19.
J Fluoresc ; 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38625573

RESUMEN

By employing a mixed-ligand strategy, we synthesized two new coordination polymers (CPs) featuring Co(II): {Co(H2L)(bib)]·2H2O}n (1) and {Co(L)(bib)2]·2H2O}n (2), where H4L represents 5-(3,5-dicarboxybenzyloxy) isophthalic acid, and bib denotes 1,4-bis(1-imidazolyl)benzene. These CPs were obtained through the reaction of H4L, a flexible carboxylic acid ligand, with Co(NO3)2·6H2O in various solvent mixtures, along with the N-donor co-ligand bib. Complexes 1 and 2 are formed through distinct coordination modes, resulting in their distinct structural features and excellent fluorescent properties. Based on ligand-centered fluorescence emission and the blue shift (CP 1) along with red shift (CP 2) characteristics, both complexes show promise for applications in fields such as blue fluorescence sensing materials and luminescent materials. After successfully synthesizing two CPs, CP 1 was chosen as the carrier for loading temozolomide (TMZ). Subsequently, leveraging the unique advantages of hydrogels, we developed a novel metal gel formulation loaded with TMZ. The inhibitory effect of this formulation on the growth of glioblastoma was evaluated. Our results demonstrate a significant suppression of glioblastoma cell proliferation by this system, providing an effective avenue for glioblastoma treatment.

20.
Artículo en Inglés | MEDLINE | ID: mdl-38319470

RESUMEN

PURPOSE: Acute kidney injury (AKI) following anticoagulant application has received growing attention as a significant emerging complication of anticoagulation. Nevertheless, there remains a lack of real-world studies to compare the incidence, clinical features, and prognosis of AKI across different anticoagulant regimens. METHODS: Disproportionality analysis and Bayesian analysis were used to identify suspected AKI cases after different anticoagulant use within the Food and Drug Administration's Adverse Event Reporting System from January 2004 to March 2023. The time to onset, fatality, and hospitalization rates of anticoagulant-associated AKI were also investigated. RESULTS: We identified 9313 anticoagulant-associated AKIs, which appeared to influence mostly patients over 65 years old (65.37%). Lepirudin displayed a stronger AKI association than others, based on the highest reporting odds ratio (ROR = 6.66, 95% CI = 3.97-11.18), proportional reporting ratio (PRR = 6.08, χ2 = 69.12), and empirical Bayes geometric mean (EBGM = 6.08, the lower 90% one-sided CI = 3.95). Warfarin showed the slightest association with AKI in oral anticoagulants, lower than any direct oral anticoagulants excluding apixaban. Edoxaban exhibited the highest potential renal risk among direct oral anticoagulants, with an ROR of 3.32 (95% CI = 2.95-3.72). The median time to AKI onset was 36 (IQR 7-205) days following the initiation of anticoagulation therapy, and most AKI cases occurred within the first month. CONCLUSION: Particular attention should be directed toward monitoring renal function in individuals receiving anticoagulants, including warfarin and direct oral anticoagulants, as well as other anticoagulant agents. This diligence is particularly imperative within the first month after anticoagulant administration for individuals with a tendency for AKI.

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