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1.
Nat Immunol ; 24(10): 1762-1777, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37653247

RESUMEN

Multivalent viral epitopes induce rapid, robust and T cell-independent humoral immune responses, but the biochemical basis for such potency remains incompletely understood. We take advantage of a set of liposomes of viral size engineered to display affinity mutants of the model antigen (Ag) hen egg lysozyme. Particulate Ag induces potent 'all-or-none' B cell responses that are density dependent but affinity independent. Unlike soluble Ag, particulate Ag induces signal amplification downstream of the B cell receptor by selectively evading LYN-dependent inhibitory pathways and maximally activates NF-κB in a manner that mimics T cell help. Such signaling induces MYC expression and enables even low doses of particulate Ag to trigger robust B cell proliferation in vivo in the absence of adjuvant. We uncover a molecular basis for highly sensitive B cell responses to viral Ag display that is independent of encapsulated nucleic acids and is not merely accounted for by avidity and B cell receptor cross-linking.


Asunto(s)
Antígenos , Linfocitos B , Receptores de Antígenos de Linfocitos B/metabolismo , Activación de Linfocitos , Epítopos/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(1): e2315242121, 2024 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-38154064

RESUMEN

High-risk neuroblastoma (NB) is a significant clinical challenge. MYCN and Anaplastic Lymphoma Kinase (ALK), which are often involved in high-risk NB, lead to increased replication stress in cancer cells, suggesting therapeutic strategies. We previously identified an ATR (ataxia telangiectasia and Rad3-related)/ALK inhibitor (ATRi/ALKi) combination as such a strategy in two independent genetically modified mouse NB models. Here, we identify an underlying molecular mechanism, in which ALK signaling leads to phosphorylation of ATR and CHK1, supporting an effective DNA damage response. The importance of ALK inhibition is supported by mouse data, in which ATRi monotreatment resulted in a robust initial response, but subsequent relapse, in contrast to a 14-d ALKi/ATRi combination treatment that resulted in a robust and sustained response. Finally, we show that the remarkable response to the 14-d combined ATR/ALK inhibition protocol reflects a robust differentiation response, reprogramming tumor cells to a neuronal/Schwann cell lineage identity. Our results identify an ability of ATR inhibition to promote NB differentiation and underscore the importance of further exploring combined ALK/ATR inhibition in NB, particularly in high-risk patient groups with oncogene-induced replication stress.


Asunto(s)
Neuroblastoma , Proteínas Tirosina Quinasas Receptoras , Humanos , Ratones , Animales , Quinasa de Linfoma Anaplásico/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Proliferación Celular , Línea Celular Tumoral , Neuroblastoma/tratamiento farmacológico , Neuroblastoma/genética , Neuroblastoma/patología , Reparación del ADN , Daño del ADN , Proteínas de la Ataxia Telangiectasia Mutada/genética
3.
Plant Cell ; 35(8): 2887-2909, 2023 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-37132483

RESUMEN

The phytohormone ethylene plays an important role in promoting the softening of climacteric fruits, such as apples (Malus domestica); however, important aspects of the underlying regulatory mechanisms are not well understood. In this study, we identified apple MITOGEN-ACTIVATED PROTEIN KINASE 3 (MdMAPK3) as an important positive regulator of ethylene-induced apple fruit softening during storage. Specifically, we show that MdMAPK3 interacts with and phosphorylates the transcription factor NAM-ATAF1/2-CUC2 72 (MdNAC72), which functions as a transcriptional repressor of the cell wall degradation-related gene POLYGALACTURONASE1 (MdPG1). The increase in MdMAPK3 kinase activity was induced by ethylene, which promoted the phosphorylation of MdNAC72 by MdMAPK3. Additionally, MdPUB24 functions as an E3 ubiquitin ligase to ubiquitinate MdNAC72, resulting in its degradation via the 26S proteasome pathway, which was enhanced by ethylene-induced phosphorylation of MdNAC72 by MdMAPK3. The degradation of MdNAC72 increased the expression of MdPG1, which in turn promoted apple fruit softening. Notably, using variants of MdNAC72 that were mutated at specific phosphorylation sites, we observed that the phosphorylation state of MdNAC72 affected apple fruit softening during storage. This study thus reveals that the ethylene-MdMAPK3-MdNAC72-MdPUB24 module is involved in ethylene-induced apple fruit softening, providing insights into climacteric fruit softening.


Asunto(s)
Malus , Malus/genética , Malus/metabolismo , Frutas/metabolismo , Fosforilación , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Etilenos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulación de la Expresión Génica de las Plantas
4.
J Immunol ; 213(8): 1061-1075, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39212443

RESUMEN

Class-switched neutralizing Ab (nAb) production is rapidly induced upon many viral infections. However, due to the presence of multiple components in virions, the precise biochemical and biophysical signals from viral infections that initiate nAb responses remain inadequately defined. Using a reductionist system of synthetic virus-like structures, in this study, we show that a foreign protein on a virion-sized liposome can serve as a stand-alone danger signal to initiate class-switched nAb responses without T cell help or TLR but requires CD19. Introduction of internal nucleic acids (iNAs) obviates the need for CD19, lowers the epitope density (ED) required to elicit the Ab response, and transforms these structures into highly potent immunogens that rival conventional virus-like particles in their ability to elicit strong Ag-specific IgG. As early as day 5 after immunization, structures harboring iNAs and decorated with just a few molecules of surface Ag at doses as low as 100 ng induced all IgG subclasses of Ab in mice and reproduced the IgG2a/2c restriction that is long observed in live viral infections. These findings reveal a shared mechanism for the nAb response in mice. High ED is capable but not necessary for driving Ab secretion. Instead, even a few molecules of surface Ag, when combined with nucleic acids within these structures, can trigger strong IgG production. As a result, the signaling threshold for induction of IgG in individual B cells is set by dual signals originating from both ED on the surface and the presence of iNAs within viral particulate immunogens.


Asunto(s)
Anticuerpos Neutralizantes , Inmunoglobulina G , Transducción de Señal , Animales , Ratones , Inmunoglobulina G/inmunología , Transducción de Señal/inmunología , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Ratones Endogámicos C57BL , Cambio de Clase de Inmunoglobulina/inmunología , Antígenos CD19/inmunología , Ratones Noqueados , Liposomas/inmunología
5.
Proc Natl Acad Sci U S A ; 120(8): e2216479120, 2023 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-36791109

RESUMEN

Anaplastic lymphoma kinase (ALK) fusion variants in Non-Small Cell Lung Cancer (NSCLC) consist of numerous dimerizing fusion partners. Retrospective investigations suggest that treatment benefit in response to ALK tyrosine kinase inhibitors (TKIs) differs dependent on the fusion variant present in the patient tumor. Therefore, understanding the oncogenic signaling networks driven by different ALK fusion variants is important. To do this, we developed controlled inducible cell models expressing either Echinoderm Microtubule Associated Protein Like 4 (EML4)-ALK-V1, EML4-ALK-V3, Kinesin Family Member 5B (KIF5B)-ALK, or TRK-fused gene (TFG)-ALK and investigated their transcriptomic and proteomic responses to ALK activity modulation together with patient-derived ALK-positive NSCLC cell lines. This allowed identification of both common and isoform-specific responses downstream of these four ALK fusions. An inflammatory signature that included upregulation of the Serpin B4 serine protease inhibitor was observed in both ALK fusion inducible and patient-derived cells. We show that Signal transducer and activator of transcription 3 (STAT3), Nuclear Factor Kappa B (NF-κB) and Activator protein 1 (AP1) are major transcriptional regulators of SERPINB4 downstream of ALK fusions. Upregulation of SERPINB4 promotes survival and inhibits natural killer cell-mediated cytotoxicity, which has potential for therapeutic impact targeting the immune response together with ALK TKIs in NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Serpinas , Humanos , Quinasa de Linfoma Anaplásico/genética , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Oncogenes , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/genética , Proteómica , Estudios Retrospectivos , Serpinas/genética
6.
EMBO J ; 40(3): e105784, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33411331

RESUMEN

High-risk neuroblastoma (NB) is responsible for a disproportionate number of childhood deaths due to cancer. One indicator of high-risk NB is amplification of the neural MYC (MYCN) oncogene, which is currently therapeutically intractable. Identification of anaplastic lymphoma kinase (ALK) as an NB oncogene raised the possibility of using ALK tyrosine kinase inhibitors (TKIs) in treatment of patients with activating ALK mutations. 8-10% of primary NB patients are ALK-positive, a figure that increases in the relapsed population. ALK is activated by the ALKAL2 ligand located on chromosome 2p, along with ALK and MYCN, in the "2p-gain" region associated with NB. Dysregulation of ALK ligand in NB has not been addressed, although one of the first oncogenes described was v-sis that shares > 90% homology with PDGF. Therefore, we tested whether ALKAL2 ligand could potentiate NB progression in the absence of ALK mutation. We show that ALKAL2 overexpression in mice drives ALK TKI-sensitive NB in the absence of ALK mutation, suggesting that additional NB patients, such as those exhibiting 2p-gain, may benefit from ALK TKI-based therapeutic intervention.


Asunto(s)
Citocinas/genética , Citocinas/metabolismo , Proteína Proto-Oncogénica N-Myc/metabolismo , Neuroblastoma/patología , Inhibidores de Proteínas Quinasas/farmacología , Regulación hacia Arriba , Quinasa de Linfoma Anaplásico/genética , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Mutación con Ganancia de Función , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Proteína Proto-Oncogénica N-Myc/genética , Neuroblastoma/genética , Neuroblastoma/metabolismo , Análisis de Secuencia de ARN , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Clin Immunol ; 259: 109880, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38142902

RESUMEN

Monocyte aberrations have been increasingly recognized as contributors to renal damage in systemic lupus erythematosus (SLE), however, recognition of the underlying mechanisms and modulating strategies is at an early stage. Our studies have demonstrated that brain-derived neurotrophic factor precursor (proBDNF) drives the progress of SLE by perturbing antibody-secreting B cells, and proBDNF facilitates pro-inflammatory responses in monocytes. By utilizing peripheral blood from patients with SLE, GEO database and spontaneous MRL/lpr lupus mice, we demonstrated in the present study that CX3CR1+ patrolling monocytes (PMo) numbers were decreased in SLE. ProBDNF was specifically expressed in CX3CR1+ PMo and was closely correlated with disease activity and the degree of renal injury in SLE patients. In MRL/lpr mice, elevated proBDNF was found in circulating PMo and the kidney, and blockade of proBDNF restored the balance of circulating and kidney-infiltrating PMo. This blockade also led to the reversal of pro-inflammatory responses in monocytes and a noticeable improvement in renal damage in lupus mice. Overall, the results indicate that the upregulation of proBDNF in PMo plays a crucial role in their infiltration into the kidney, thereby contributing to nephritis in SLE. Targeting of proBDNF offers a potential therapeutic role in modulating monocyte-driven renal damage in SLE.


Asunto(s)
Lupus Eritematoso Sistémico , Nefritis Lúpica , Animales , Humanos , Ratones , Riñón , Ratones Endogámicos MRL lpr , Monocitos , Regulación hacia Arriba , Precursores de Proteínas
8.
Biochem Biophys Res Commun ; 696: 149472, 2024 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-38241809

RESUMEN

Lysosomal dysfunction and impaired autophagic flux are involved in the pathogenesis of lipotoxicity in the kidney. Here, we investigated the role of transcription factor EB (TFEB), a master regulator of autophagy-lysosomal pathway, in palmitic acid induced renal tubular epithelial cells injury. We examined lipid accumulation, autophagic flux, expression of Ps211-TFEB, and nuclear translocation of TFEB in HK-2 cells overloaded with palmitic acid (PA). By utilizing immunohistochemistry, we detected TFEB expression in renal biopsy tissues from patients with diabetic nephropathy and normal renal tissue adjacent to surgically removed renal carcinoma (controls), as well as kidney tissues from rat fed with high-fat diet (HFD) and low-fat diet (LFD). We found significant lipid accumulation, increased apoptosis, accompanied with elevated Ps211-TFEB, decreased nuclear TFEB, reduced lysosome biogenesis and insufficient autophagy in HK-2 cells treated with PA. Kidney tissues from patients with diabetic nephropathy had lower nuclear and total levels of TFEB than that in control kidney tissues. Level of renal nuclear TFEB in HFD rats was also lower than that in LFD rats. Exogenous overexpression of TFEB increased the nuclear TFEB level in HK-2 cells treated with PA, promoted lysosomal biogenesis, improved autophagic flux, reduced lipid accumulation and apoptosis. Our results collectively indicate that PA is a strong inducer for TFEB phosphorylation modification at ser211 accompanied with lower nuclear translocation of TFEB. Impairment of TFEB-mediated lysosomal biogenesis and function by palmitic acid may lead to insufficient autophagy and promote HK-2 cells injury.


Asunto(s)
Nefropatías Diabéticas , Ácido Palmítico , Ratas , Humanos , Animales , Ácido Palmítico/farmacología , Ácido Palmítico/metabolismo , Nefropatías Diabéticas/metabolismo , Autofagia , Lisosomas/metabolismo , Células Epiteliales/metabolismo , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo
9.
Artículo en Inglés | MEDLINE | ID: mdl-39254769

RESUMEN

BACKGROUND: Double-negative T (DNT) cells comprise a distinct subset of T lymphocytes that have been implicated in immune responses. The aim of this study was to characterize the peripheral DNT population in breast cancer (BC) patients. METHODS: DNT cells were isolated from the peripheral blood samples of BC patients and healthy controls by flow cytometry. The sorted DNT cells were analyzed by the Smart-seq2 for single-cell full-length transcriptome profiling. The differentially expressed genes (DEGs) between the BC and control groups were screened and functionally annotated by Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses using R. The protein-protein interaction (PPI) network of the DEGs was constructed using the CytoHubba and MCODE plug-in of Cytoscape software to identify the core genes. Survival status, DNA methylation level, immune infiltration and immune checkpoint expression were analyzed using Kaplan-Meier Plotter, UALCAN, MethSeuvr, TIMER, and TISIDB respectively. The sequencing results were verified by RT-qPCR. RESULT: The percentage of DNT cells was higher in the BC patients compared to healthy controls. We identified 289 DEGs between the DNT populations of both groups. GO and KEGG pathway analyses revealed that the DEGs were mainly related to immunoglobulin mediated immune response, complement activation, and B cell receptor signaling. The PPI networks of the common DEGs were constructed using Cytoscape, and 10 core genes were identified, including TMEM176B, C1QB, C1QC, RASD2, and IFIT3. The expression levels of these genes correlated with the prognosis and immune infiltration in BC patients, and were validated by RT-qPCR (P < 0.05). CONCLUSIONS: DNT cells are abundant in patients with BC, and might exert anti-tumor immune responses by regulating genes such as TMEM176B and EGR1.

10.
Small ; : e2403679, 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39240068

RESUMEN

Diabetic wounds tend to develop into nonhealing wounds associated with the complex inflammatory microenvironment of uncontrollable bacterial infection, reactive oxygen species (ROS) accumulation, and chronic hypoxia. Damaged blood vessels hinder metabolic circulation, aggravating hypoxia, and ROS accumulation and further exacerbating the diabetic wound microenvironment. However, existing treatments with a single functionality have difficulty healing complicated diabetic wounds. Therefore, developing an integrative strategy to improve the hostility of the diabetic wound microenvironment is urgently needed. Herein, multifunctional genipin (GP)-crosslinked chitosan (CS)-based hydrogels decorated with the biomimetic metal-organic framework (MOF)-nanozymes and the natural antibacterial agent chlorogenic acid (CGA), which is named MOF/CGA@GP-CS (MCGC), are prepared. With catalase (CAT)-like activity, these dual-metal MOF-nanozymes are promising bioreactors for simultaneously alleviating ROS accumulation and hypoxia by converting elevated endogenous H2O2 into dissolved oxygen in diabetic wounds. In addition, the other component of natural polyphenolic CGA acts as a mild antibacterial agent, efficiently inhibiting wound infection and avoiding antibiotic resistance. Impressively, the MCGC hydrogels accelerate infected diabetic wound healing by eliminating oxidative stress, increasing oxygenation, and reversing bacterial infection in vivo. In this work, an effective strategy based on multifunctional hydrogel wound dressings is successfully developed and applied in diabetic wound management.

11.
Plant Physiol ; 191(1): 694-714, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-36287070

RESUMEN

The plant hormone ethylene plays a central role in the ripening of climacteric fruits, such as apple (Malus domestica). Ethylene biosynthesis in apple fruit can be suppressed by calcium ions (Ca2+); however, the underlying mechanism is largely unknown. In this study, we identified an apple APETALA2/ETHYLENE-RESPONSIVE FACTOR (AP2/ERF) transcription factor, MdCYTOKININ RESPONSE FACTOR4 (MdCRF4), which functions as a transcriptional activator of ethylene biosynthesis- and signaling-related genes, including Md1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID SYNTHASE1 (MdACS1) and MdETHYLENE-RESPONSIVE FACTOR3 (MdERF3), as a partner of the calcium sensor, calmodulin. Ca2+ promoted the Ca2+/CaM2-mediated phosphorylation of MdCRF4, resulting in MdCRF4 recognition by the E3 ubiquitin ligase MdXB3 ORTHOLOG 1 IN ARABIDOPSIS THALIANA (MdXBAT31), and consequently its ubiquitination and degradation via the 26S proteasome pathway. This in turn resulted in lower expression of MdACS1 and MdERF3 and reduced ethylene biosynthesis. Transiently overexpressing various MdCRF4 proteins with specific mutated phosphorylation sites revealed that the phosphorylation state of MdCRF4 affects the ripening of apple fruit. The results reveal that a Ca2+/CaM-MdCRF4-MdXBAT31 module is involved in Ca2+-suppressed ethylene biosynthesis, which delays apple fruit ripening. This provides insights into fruit ripening that may result in strategies for extending fruit shelf life.


Asunto(s)
Malus , Malus/genética , Malus/metabolismo , Frutas/metabolismo , Calcio/metabolismo , Fosforilación , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Etilenos/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Regulación de la Expresión Génica de las Plantas
12.
Plant Physiol ; 191(4): 2475-2488, 2023 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-36653326

RESUMEN

Ethylene biosynthesis in apple (Malus domestica) fruit can be suppressed by calcium ions (Ca2+) during storage; however, the underlying mechanisms are unclear. In this study, we identified the apple transcription factor MCM1-AGAMOUS-DEFICIENS-SRF5 (MdMADS5), which functions as a transcriptional activator of the ethylene biosynthesis-related gene 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID SYNTHASE1 (MdACS1), a partner of the calcium sensor CALCIUM-DEPENDENT PROTEIN KINASES7 (MdCDPK7). Ca2+ promoted the MdCDPK7-mediated phosphorylation of MdMADS5, which resulted in the degradation of MdMADS5 via the 26S proteasome pathway. MdCDPK7 also phosphorylated 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID OXIDASE1 (MdACO1), the key enzyme in ethylene biosynthesis, leading to MdACO1 degradation and inhibition of ethylene biosynthesis. Our results reveal that Ca2+/MdCDPK7-MdMADS5 and Ca2+/MdCDPK7-MdACO1 are involved in Ca2+-suppressed ethylene biosynthesis, which delays apple fruit ripening. These findings provide insights into fruit ripening, which may lead to the development of strategies for extending the shelf life of fruit.


Asunto(s)
Malus , Malus/metabolismo , Calcio/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Fosforilación , Etilenos/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Frutas/metabolismo
13.
Biomacromolecules ; 25(1): 143-154, 2024 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-38054613

RESUMEN

Hydrogel-based flexible strain sensors have been known for their excellent ability to convert different motions of humans into electrical signals, thus enabling real-time monitoring of various human health parameters. In this work, a composite hydrogel with hydrophobic association and hybrid cross-linking was fabricated by using polyacrylamide (PAm), surfactant sodium dodecyl sulfate (SDS), lauryl methacrylate (LMA), and polypyrrole (PPy). The dynamic dissociation-conjugation among LMA, SDS, and PPy could dissipate energy to improve the toughness of hydrogels. The SDS/PPy/LMPAm composite hydrogel with a toughness of 1.44 MJ/m3, tensile fracture stress of 345 kPa, tensile strain of 1021%, and electrical conductivity of 0.57 S/m was obtained. Furthermore, an interdigital electrode flexible pressure sensor was designed to replace the bipolar electrode flexible pressure sensor, which greatly improved the sensitivity and resolution of the pressure sensor. The SDS/PPy/LMPAm composite hydrogel-based interdigital electrode flexible pressure sensor showed extraordinary stability and identified different hand gestures as well as monitored the pulse signal of humans. Moreover, the characteristic systolic and diastolic peaks were clearly observed. The pulse frequency (65 times/min) and the radial artery augmentation index (0.57) were calculated, which are very important in evaluating the arterial vessel wall and function of human arteries.


Asunto(s)
Hidrogeles , Polímeros , Humanos , Pirroles , Conductividad Eléctrica , Electrodos
14.
Inorg Chem ; 63(39): 18365-18378, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39287929

RESUMEN

Metallacyclopropanes are highly strained and very reactive organometallics; the rare-earth metal complexes bearing both highly reactive electrophilic carbon and strongly polarized metallacyclopropanes are extremely rare. This type of rare-earth metal complexes (κ2-L)RE(η2-C2B10H10)·(THF)3 [L = 1-(2-N-C5H10NCH2CH2)-3-(2,6-iPr2C6H3N═CH)-C8H4N, RE = Lu(1a), Yb(1b), Er(1c), Y(1d), Dy(1e)] bearing the indol-2-yl electrophilic carbon and carboryne-based strongly polarized metallacyclopropanes have been synthesized. Structures of complexes 1 are further confirmed by single-crystal X-ray diffraction and DFT theoretical calculations. It is found that complexes 1 have remarkable reactivity toward different polar unsaturated small molecules, elemental sulfur, and selenium to provide different products (2-15) through the selective reactions of the RE-Ccage, and RE-C2-ind bonds with the given small molecules, respectively. The reactivities of these complexes are different from those of the reported rare-earth metallacyclopropenes and d-block metal-carborynes.

15.
J Hered ; 115(3): 292-301, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38364316

RESUMEN

Biodiversity conservation is a top priority in the face of global environmental change, and the practical restoration of biodiversity has emerged as a key objective. Nevertheless, the question of how to effectively contribute to biodiversity restoration and identify suitable systems for such efforts continues to present major challenges. By using genome-wide SNP data, our study revealed that populations from different mountain ranges of the Formosan Long-Arm Scarab beetle, a flagship species that receives strict protection, exhibited a single genetic cluster with no subdivision. Additionally, our result implied an association between the demographic history and historical fluctuations in climate and environmental conditions. Furthermore, we showed that, despite a stable and moderately sized effective population over recent history, all the individuals we studied exhibited signs of genetic inbreeding. We argued that the current practice of protecting the species as one evolutionarily significant unit remains the best conservation plan and that recent habitat change may have led to the pattern of significant inbreeding. We closed by emphasizing the importance of conservation genetic studies in guiding policy decisions and highlighting the potential of genomic data for identifying ideal empirical systems for genetic rescue, or assisted gene flow studies.


Asunto(s)
Escarabajos , Conservación de los Recursos Naturales , Genética de Población , Endogamia , Densidad de Población , Animales , Escarabajos/genética , Polimorfismo de Nucleótido Simple , Ecosistema , Flujo Génico , Genómica/métodos , Variación Genética , Biodiversidad
16.
Artículo en Inglés | MEDLINE | ID: mdl-39068629

RESUMEN

The prognostic value of growth differentiation factor-15 (GDF-15) in predicting long-term adverse outcomes in coronary heart disease (CHD) patients remains limited. Our study examines the association between GDF-15 and adverse outcomes over an extended period in CHD patients and firstly assesses the incremental prognostic effect of incorporating GDF-15 into the Framingham risk score (FRS)-based model. This single-center prospective cohort study included 3,321 patients with CHD categorized into 2,479 acute coronary syndrome (ACS) (74.6%) and 842 non-ACS (25.4%) groups. The median age was 61.0 years (range: 53.0-70.0), and 917 (27.6%) were females. Mortality and major adverse cardiovascular events (MACEs) included cardiovascular mortality, myocardial infarction (MI), stroke, and heart failure (HF) (inclusive of HF episodes requiring outpatient treatment and/or hospital admission). Cox regression models assessed the associations between GDF-15 and the incidence of all-cause mortality and MACEs. Patients were stratified into three groups based on GDF-15 levels: the first tertile group (< 1,370 ng/L), the second tertile group (1,370-2,556 ng/L), and the third tertile group (> 2,556 ng/L). The C-index, integrated discrimination improvement (IDI), net reclassification improvement (NRI), and decision curve analysis (DCA) were used to assess incremental value. Over a median 9.4-year follow-up, 759 patients (22.9%) died, and 1,291 (38.9%) experienced MACEs. The multivariate Cox model indicated that GDF-15 was significantly associated with all-cause mortality (per ln unit increase, HR = 1.49, 95% CI: 1.36-1.64) and MACEs (per ln unit increase, HR = 1.29, 95% CI: 1.20-1.38). These associations persisted when GDF-15 was analyzed as an ordinal variable (p for trend < 0.05). Subgroup analysis of ACS and non-ACS for the components of MACEs separately showed a significant association between GDF-15 and both cardiovascular mortality and HF, but no association was observed between GDF-15 and MI /stroke in both ACS and non-ACS patients. The addition of GDF-15 to the FRS-based model enhanced the discrimination for both all-cause mortality (∆ C-index = 0.009, 95% CI: 0.005-0.014; IDI = 0.030, 95% CI: 0.015-0.047; continuous NRI = 0.631, 95% CI: 0.569-0.652) and MACEs (∆ C-index = 0.009, 95% CI: 0.006-0.012; IDI = 0.026, 95% CI: 0.009-0.042; continuous NRI = 0.593, 95% CI: 0.478-0.682). DCA suggested that incorporating GDF-15 into the FRS-based model demonstrated higher net benefits compared to FRS-based models alone (All-cause mortality: FRS-based model: area under the curve of DCA (AUDC) = 0.0903, FRS-based model + GDF-15: AUDC = 0.0908; MACEs: FRS-based model: AUDC = 0.1806, FRS-based model + GDF-15: AUDC = 0.1833). GDF-15 significantly associates with the long-term prognosis of all-cause mortality and MACEs in CHD patients and significantly improves the prognostic accuracy of the FRS-based model for both outcomes.

17.
Ecotoxicol Environ Saf ; 272: 116085, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38342010

RESUMEN

Zearalenone (ZEN) is a prevalent mycotoxin that severely impacts human and animal health. However, the possible interactions between ZEN exposure, pathogen infection, immune system, and reactive oxygen species (ROS) were rarely investigated. We studied the effects of early-life ZEN (50 µM) exposure on the immune response of Caenorhabditis elegans against Bacillus thuringiensis infection and the associated mechanisms. The transcriptomic responses of C. elegans after early-life ZEN exposure were investigated using RNA sequencing and followed by verification using quantitative PCR analysis. We also investigated the immune responses of the worms through B. thuringiensis killing assays and by measuring oxidative stress. The transcriptomics result showed that early-life exposure to ZEN resulted in 44 differentially expressed genes, 7 of which were protein-coding genes with unknown functions. The Gene Ontology analysis suggested that metabolic processes and immune response were among the most significantly enriched biological processes, and the KEGG analysis suggested that lysosomes and metabolic pathways were the most significantly enriched pathways. The ZEN-exposed worms exhibited significantly reduced survival after 24-h B. thuringiensis infection, reaching near 100% mortality compared to 60% of the controls. Using qRT-PCR assay, we found that ZEN further enhanced the expression of immunity genes lys-6, spp-1, and clec-60 after B. thuringiensis infection. A concurrently enhanced ROS accumulation was also observed for ZEN-exposed worms after B. thuringiensis infection, which was 1.2-fold compared with the controls. Moreover, ZEN exposure further enhanced mRNA expression of catalases (ctl-1 and ctl-2) and increased catalase protein activity after B. thuringiensis exposure compared with their non-exposed counterparts, suggesting an elevated oxidative stress. This study suggests that early-life exposure to mycotoxin zearalenone overstimulates immune responses involving spp-17, clec-52, and clec-56, resulting in excessive ROS production, enhanced oxidative stress as indicated by aggravated ctl expression and activity, and a decline in host resistance to pathogenic infection which ultimately leads to increased mortality under B. thuringiensis infection. Our findings provide evidence that could improve our understanding on the potential interactions between mycotoxin zearalenone and pathogens.


Asunto(s)
Bacillus thuringiensis , Micotoxinas , Zearalenona , Animales , Humanos , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Zearalenona/toxicidad , Especies Reactivas de Oxígeno/metabolismo , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Micotoxinas/metabolismo , Estrés Oxidativo , Antioxidantes/metabolismo , Inmunidad
18.
J Asian Nat Prod Res ; 26(10): 1239-1246, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38780916

RESUMEN

A new compound, named coniferin B (1), and fourteen known compounds were purified and identified from the leaves and branches of Wikstroemia chamaedaphne Meisn. Their chemical structures were elucidated through analyzing spectroscopic and HRESIMS data. Compounds 2, 3, 5, 7-9, 11, and 13 were isolated from this plant for the first time. All compounds were assayed for cytotoxicity and activation of latent HIV activity on NH2 cells. The results showed that all compounds did not produce cytotoxicity at 10.0 µM and compounds 1, 9-11 showed weak activating activity with activation folds of 4.88, 7.14, 5.3, and 6.97, respectively.


Asunto(s)
Hojas de la Planta , Wikstroemia , Hojas de la Planta/química , Estructura Molecular , Wikstroemia/química , Humanos , VIH-1/efectos de los fármacos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/aislamiento & purificación , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/química , Fármacos Anti-VIH/aislamiento & purificación , Tallos de la Planta/química
19.
Telemed J E Health ; 30(9): 2477-2482, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38934135

RESUMEN

Background: Blurry images in teledermatology and consultation increased the diagnostic difficulty for both deep learning models and physicians. We aim to determine the extent of restoration in diagnostic accuracy after blurry images are deblurred by deep learning models. Methods: We used 19,191 skin images from a public skin image dataset that includes 23 skin disease categories, 54 skin images from a public dataset of blurry skin images, and 53 blurry dermatology consultation photos in a medical center to compare the diagnosis accuracy of trained diagnostic deep learning models and subjective sharpness between blurry and deblurred images. We evaluated five different deblurring models, including models for motion blur, Gaussian blur, Bokeh blur, mixed slight blur, and mixed strong blur. Main Outcomes and Measures: Diagnostic accuracy was measured as sensitivity and precision of correct model prediction of the skin disease category. Sharpness rating was performed by board-certified dermatologists on a 4-point scale, with 4 being the highest image clarity. Results: The sensitivity of diagnostic models dropped 0.15 and 0.22 on slightly and strongly blurred images, respectively, and deblurring models restored 0.14 and 0.17 for each group. The sharpness ratings perceived by dermatologists improved from 1.87 to 2.51 after deblurring. Activation maps showed the focus of diagnostic models was compromised by the blurriness but was restored after deblurring. Conclusions: Deep learning models can restore the diagnostic accuracy of diagnostic models for blurry images and increase image sharpness perceived by dermatologists. The model can be incorporated into teledermatology to help the diagnosis of blurry images.


Asunto(s)
Aprendizaje Profundo , Dermatología , Enfermedades de la Piel , Telemedicina , Humanos , Enfermedades de la Piel/diagnóstico , Enfermedades de la Piel/diagnóstico por imagen , Dermatología/métodos , Fotograbar
20.
Chin Med Sci J ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39256059

RESUMEN

Objective The extent to which the association between hypertension and chronic pain in observational studies is either causally linked or influenced by other shared risk factors has not been substantially addressed. In the present study, Mendelian randomization (MR) was employed to examine the potential causal relationship between hypertension and risk of chronic pain. Methods The study data were derived from the pooled dataset of the genome-wide association study (GWAS), enabling the evaluation of the causal effects of hypertension on various types of chronic pain including headache as well as chest, abdominal, joint, back, limb, and multisite chronic pain. We performed a bidirectional two-sample MR analysis using random effect inverse variance weighting (IVW), MR-Egger, and weighted median and weighted mode, quantified by the odds ratio (OR). Results Genetically predicted essential hypertension was associated with an increased risk of chronic headache (OR = 1.007, 95% CI: 1.003-1.011, P = 0.002) and limb pain (OR = 1.219, 95% CI: 1.033-1.439, P = 0.019). No potential causal associations were identified between chronic pain and essential hypertension in the reverse direction MR ( P > 0.05). In addition, there was no potential causal association between secondary hypertension and chronic pain (P > 0.05). Conclusion This study provided genetic evidence that a unidirectional causal relationship exists between essential hypertension and the increased risks of chronic headache and limb pain, and no causal relationship was found between secondary hypertension and chronic pain. These findings offer crucial theoretical underpinnings for future research on managing hypertension and chronic pain.

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