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1.
J Immunol ; 212(6): 1012-1021, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38251913

RESUMEN

It is becoming clear that every organ is seeded by a population of fetal liver-derived macrophages that are replaced at different rates by monocyte-derived macrophages. Using the Ms4a3tdTomato reporter mouse that reports on monocyte-derived alveolar macrophages (Mo-AMs) and our ability to examine AM function using our multichannel intravital microscopy, we examined the fetal-liver derived alveolar macrophage (FL-AM) and Mo-AM populations within the same mouse under various environmental conditions. The experiments unveiled that AMs migrated from alveolus to alveolus and phagocytosed bacteria identically regardless of ontogenic origin. Using 50 PFU of influenza A virus (IAV) determined using the Madin-Darby canine kidney (MDCK) cell line, we noted that both populations were susceptible to IAV-induced immunoparalysis, which also led to impaired phagocytosis of secondary bacterial infections. Both FL-AMs and Mo-AMs were trained by ß-glucan to resist IAV-induced paralysis. Over time (40 wk), Mo-AMs began to outperform FL-AMs, although both populations were still sensitive to IAV. Our data also show that clodronate depletion of AMs leads to replenishment, but by FL-AMs, and these macrophages do show some functional impairment for a limited time. Overall, the system is designed such that new macrophages rapidly assume the function of tissue-resident macrophages when both populations are examined in an identical environment. These data do differ from artificial depletion methods that compare Mo-AMs and FL-AMs.


Asunto(s)
Coinfección , Virus de la Influenza A , Animales , Perros , Ratones , Pulmón , Macrófagos , Macrófagos Alveolares , Fagocitosis , Hígado
2.
Mol Biol Evol ; 41(8)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39136558

RESUMEN

Sex chromosomes display remarkable diversity and variability among vertebrates. Compared with research on the X/Y and Z/W chromosomes, which have long evolutionary histories in mammals and birds, studies on the sex chromosomes at early evolutionary stages are limited. Here, we precisely assembled the genomes of homozygous XX female and YY male Lanzhou catfish (Silurus lanzhouensis) derived from an artificial gynogenetic family and a self-fertilized family, respectively. Chromosome 24 (Chr24) was identified as the sex chromosome based on resequencing data. Comparative analysis of the X and Y chromosomes showed an approximate 320 kb Y-specific region with a Y-specific duplicate of anti-Mullerian hormone type II receptor (amhr2y), which is consistent with findings in 2 other Silurus species but on different chromosomes (Chr24 of Silurus meridionalis and Chr5 of Silurus asotus). Deficiency of amhr2y resulted in male-to-female sex reversal, indicating that amhr2y plays a male-determining role in S. lanzhouensis. Phylogenetic analysis and comparative genomics revealed that the common sex-determining gene amhr2y was initially translocated to Chr24 of the Silurus ancestor along with the expansion of transposable elements. Chr24 was maintained as the sex chromosome in S. meridionalis and S. lanzhouensis, whereas a sex-determining region transition triggered sex chromosome turnover from Chr24 to Chr5 in S. asotus. Additionally, gene duplication, translocation, and degeneration were observed in the Y-specific regions of Silurus species. These findings present a clear case for the early evolutionary trajectory of sex chromosomes, including sex-determining gene origin, repeat sequence expansion, gene gathering and degeneration in sex-determining region, and sex chromosome turnover.


Asunto(s)
Bagres , Procesos de Determinación del Sexo , Animales , Masculino , Femenino , Bagres/genética , Evolución Molecular , Filogenia , Cromosomas Sexuales/genética , Cromosoma Y/genética , Genoma , Cromosoma X/genética , Receptores de Péptidos , Receptores de Factores de Crecimiento Transformadores beta
3.
PLoS Genet ; 18(6): e1010288, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35767574

RESUMEN

Although evolutionary fates and expression patterns of duplicated genes have been extensively investigated, how duplicated genes co-regulate a biological process in polyploids remains largely unknown. Here, we identified two gsdf (gonadal somatic cell-derived factor) homeologous genes (gsdf-A and gsdf-B) in hexaploid gibel carp (Carassius gibelio), wherein each homeolog contained three highly conserved alleles. Interestingly, gsdf-A and gsdf-B transcription were mainly activated by dmrt1-A (dsx- and mab-3-related transcription factor 1) and dmrt1-B, respectively. Loss of either gsdf-A or gsdf-B alone resulted in partial male-to-female sex reversal and loss of both caused complete sex reversal, which could be rescued by a nonsteroidal aromatase inhibitor. Compensatory expression of gsdf-A and gsdf-B was observed in gsdf-B and gsdf-A mutants, respectively. Subsequently, we determined that in tissue culture cells, Gsdf-A and Gsdf-B both interacted with Ncoa5 (nuclear receptor coactivator 5) and blocked Ncoa5 interaction with Rora (retinoic acid-related orphan receptor-alpha) to repress Rora/Ncoa5-induced activation of cyp19a1a (cytochrome P450, family 19, subfamily A, polypeptide 1a). These findings illustrate that Gsdf-A and Gsdf-B can regulate male differentiation by inhibiting cyp19a1a transcription in hexaploid gibel carp and also reveal that Gsdf-A and Gsdf-B can interact with Ncoa5 to suppress cyp19a1a transcription in vitro. This study provides a typical case of cooperative mechanism of duplicated genes in polyploids and also sheds light on the conserved evolution of sex differentiation.


Asunto(s)
Gónadas , Diferenciación Sexual , Animales , Diferenciación Celular/genética , Femenino , Proteínas de Peces/genética , Peces/genética , Regulación del Desarrollo de la Expresión Génica , Gónadas/metabolismo , Masculino , Poliploidía , Diferenciación Sexual/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
4.
J Allergy Clin Immunol ; 153(4): 1025-1039, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38072196

RESUMEN

BACKGROUND: Ectopic lymphoid tissues (eLTs) and associated follicular helper T (TFH) cells contribute to local immunoglobulin hyperproduction in nasal polyps (NPs). Follicular regulatory T (TFR) cells in secondary lymphoid organs counteract TFH cells and suppress immunoglobulin production; however, the presence and function of TFR cells in eLTs in peripheral diseased tissues remain poorly understood. OBJECTIVE: We sought to investigate the presence, phenotype, and function of TFR cells in NPs. METHODS: The presence, abundance, and phenotype of TFR cells in NPs were examined using single-cell RNA sequencing, immunofluorescence staining, and flow cytometry. Sorted polyp and circulating T-cell subsets were cocultured with autologous circulating naïve B cells, and cytokine and immunoglobulin production were measured by ELISA. RESULTS: TFR cells were primarily localized within eLTs in NPs. TFR cell frequency and TFR cell/TFH cell ratio were decreased in NPs with eLTs compared with NPs without eLTs and control inferior turbinate tissues. TFR cells displayed an overlapping phenotype with TFH cells and FOXP3+ regulatory T cells in NPs. Polyp TFR cells had reduced CTLA-4 expression and decreased capacity to inhibit TFH cell-induced immunoglobulin production compared with their counterpart in blood and tonsils. Blocking CTLA-4 abolished the suppressive effect of TFR cells. Lower vitamin D receptor expression was observed on polyp TFR cells compared with TFR cells in blood and tonsils. Vitamin D treatment upregulated CTLA-4 expression on polyp TFR cells and restored their suppressive function in vitro. CONCLUSIONS: Polyp TFR cells in eLTs have decreased CLTA-4 and vitamin D receptor expression and impaired capacity to suppress TFH cell-induced immunoglobulin production, which can be reversed by vitamin D treatment in vitro.


Asunto(s)
Pólipos Nasales , Estructuras Linfoides Terciarias , Humanos , Linfocitos T Reguladores/patología , Linfocitos T Colaboradores-Inductores/patología , Antígeno CTLA-4/metabolismo , Receptores de Calcitriol/metabolismo , Pólipos Nasales/patología , Estructuras Linfoides Terciarias/patología , Inmunoglobulinas/metabolismo , Vitamina D/metabolismo
5.
Mol Cancer ; 23(1): 213, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39342168

RESUMEN

The pursuit of innovative therapeutic strategies in oncology remains imperative, given the persistent global impact of cancer as a leading cause of mortality. Immunotherapy is regarded as one of the most promising techniques for systemic cancer therapies among the several therapeutic options available. Nevertheless, limited immune response rates and immune resistance urge us on an augmentation for therapeutic efficacy rather than sticking to conventional approaches. Ferroptosis, a novel reprogrammed cell death, is tightly correlated with the tumor immune environment and interferes with cancer progression. Highly mutant or metastasis-prone tumor cells are more susceptible to iron-dependent nonapoptotic cell death. Consequently, ferroptosis-induction therapies hold the promise of overcoming resistance to conventional treatments. The most prevalent post-transcriptional modification, RNA m6A modification, regulates the metabolic processes of targeted RNAs and is involved in numerous physiological and pathological processes. Aberrant m6A modification influences cell susceptibility to ferroptosis, as well as the expression of immune checkpoints. Clarifying the regulation of m6A modification on ferroptosis and its significance in tumor cell response will provide a distinct method for finding potential targets to enhance the effectiveness of immunotherapy. In this review, we comprehensively summarized regulatory characteristics of RNA m6A modification on ferroptosis and discussed the role of RNA m6A-mediated ferroptosis on immunotherapy, aiming to enhance the effectiveness of ferroptosis-sensitive immunotherapy as a treatment for immune-resistant malignancies.


Asunto(s)
Ferroptosis , Inmunoterapia , Neoplasias , Ferroptosis/genética , Humanos , Neoplasias/terapia , Neoplasias/inmunología , Neoplasias/genética , Neoplasias/patología , Neoplasias/metabolismo , Inmunoterapia/métodos , Animales , Adenosina/análogos & derivados , Adenosina/metabolismo , Regulación Neoplásica de la Expresión Génica , Procesamiento Postranscripcional del ARN , Metilación de ARN
6.
Anal Chem ; 96(21): 8730-8739, 2024 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-38743814

RESUMEN

Adenosine-to-inosine (A-to-I) editing and N6-methyladenosine (m6A) modifications are pivotal RNA modifications with widespread functional significance in physiological and pathological processes. Although significant effort has been dedicated to developing methodologies for identifying and quantifying these modifications, traditional approaches have often focused on each modification independently, neglecting the potential co-occurrence of A-to-I editing and m6A modifications at the same adenosine residues. This limitation has constrained our understanding of the intricate regulatory mechanisms governing RNA function and the interplay between different types of RNA modifications. To address this gap, we introduced an innovative technique called deamination-assisted reverse transcription stalling (DARTS), specifically designed for the simultaneous quantification of A-to-I editing and m6A at the same RNA sites. DARTS leverages the selective deamination activity of the engineered TadA-TadA8e protein, which converts adenosine residues to inosine, in combination with the unique property of Bst 2.0 DNA polymerase, which stalls when encountering inosine during reverse transcription. This approach enables the accurate quantification of A-to-I editing, m6A, and unmodified adenosine at identical RNA sites. The DARTS method is remarkable for its ability to directly quantify two distinct types of RNA modifications simultaneously, a capability that has remained largely unexplored in the field of RNA biology. By facilitating a comprehensive analysis of the co-occurrence and interaction between A-to-I editing and m6A modifications, DARTS opens new avenues for exploring the complex regulatory networks modulated by different RNA modifications.


Asunto(s)
Adenosina , Inosina , Edición de ARN , Adenosina/análogos & derivados , Adenosina/análisis , Adenosina/metabolismo , Inosina/metabolismo , Inosina/análogos & derivados , Inosina/química , Desaminación , ARN/metabolismo , ARN/genética , ARN/análisis , Transcripción Reversa , Humanos
7.
Cancer Immunol Immunother ; 73(7): 132, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753055

RESUMEN

BACKGROUND: Immune checkpoint inhibitors (ICIs) combined with chemotherapy have become the first-line treatment of metastatic gastric and gastroesophageal adenocarcinomas (GEACs). This study aims to figure out the optimal combined positive score (CPS) cutoff value. METHODS: We searched for randomized phase III trials to investigate the efficacy of ICIs plus chemotherapy for metastatic GEACs compared with chemotherapy alone. Pooled analyses of hazard ratios (HRs) based on PD-L1 expression were performed. RESULTS: A total of six trials (KEYNOTE-062, KEYNOTE-590, KEYNOTE-859, ATTRACTION-04, CheckMate 649, and ORIENT-16) were included, comprising 5,242 patients. ICIs plus chemotherapy significantly improved OS (HR: 0.79, 95% CI 0.72-0.86 in global patients; HR: 0.75, 95% CI 0.57-0.98 in Asian patients) and PFS (HR: 0.74, 95% CI 0.68-0.82 in global patients; HR: 0.64, 95% CI 0.56-0.73 in Asian patients) compared with chemotherapy alone. The differences in OS (ratio of HR: 1.05, 95% CI 0.79-1.40; predictive value: - 5.1%) and PFS (ratio of HR: 1.16, 95% CI 0.98-1.36; predictive value: - 13.5%) were not statistically significant between the global and Asian patients. Subgroup analyses indicated that the optimal CPS threshold was at ≥ 5 for OS and ≥ 10 for PFS with the highest predictive values. CONCLUSIONS: The benefit derived from ICIs plus chemotherapy is similar between Asian and global GEAC patients. However, those with a PD-L1 CPS < 5 or CPS < 10 may not have significant benefits from ICIs therapy. Therefore, it is advisable to routinely assess PD-L1 expression in GEAC patients considered for ICIs treatment.


Asunto(s)
Adenocarcinoma , Protocolos de Quimioterapia Combinada Antineoplásica , Antígeno B7-H1 , Inhibidores de Puntos de Control Inmunológico , Receptor ErbB-2 , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidad , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inhibidores , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/mortalidad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Receptor ErbB-2/metabolismo , Pronóstico , Ensayos Clínicos Controlados Aleatorios como Asunto , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Ensayos Clínicos Fase III como Asunto , Biomarcadores de Tumor/metabolismo
8.
PLoS Pathog ; 18(6): e1010626, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35727817

RESUMEN

From insects to mammals, both innate and adaptive immune response are usually higher in females than in males, with the sex chromosome and hormonal differences considered the main reasons. Here, we report that zebrafish cyp19a1a (cytochrome P450, family 19, subfamily A, polypeptide 1a), an autosomal gene with female-biased expression, causes female fish to exhibit a lower antiviral response. First, we successfully constructed an infection model by intraperitoneal injection of spring viremia of carp virus (SVCV) into zebrafish (Danio rerio) and Carassius auratus herpesvirus (CaHV) in gibel carp (Carassius gibelio). Specifically, female fish were more vulnerable to viral infection than males, accompanied by a significantly weaker interferon (IFN) expression. After screening several candidates, cyp19a1a, which was highly expressed in female fish tissues, was selected for further analysis. The IFN expression and antiviral response were significantly higher in cyp19a1a-/- than in cyp19a1a+/+. Further investigation of the molecular mechanism revealed that Cyp19a1a targets mediator of IRF3 activation (MITA) for autophagic degradation. Interestingly, in the absence of MITA, Cyp19a1a alone could not elicit an autophagic response. Furthermore, the autophagy factor ATG14 (autophagy-related 14) was found interacted with Cyp19a1a to either promote or attenuate Cyp19a1a-mediated MITA degradation by either being overexpressed or knocked down, respectively. At the cellular level, both the normal and MITA-enhanced cellular antiviral responses were diminished by Cyp19a1a. These findings demonstrated a sex difference in the antiviral response based on a regulation mechanism controlled by a female-biased gene besides sex chromosome and hormonal differences, supplying the current understanding of sex differences in fish.


Asunto(s)
Carpas , Enfermedades de los Peces , Herpesviridae , Animales , Antivirales/farmacología , Autofagia , Femenino , Inmunidad Innata/genética , Masculino , Mamíferos , Pez Cebra/genética
9.
Plant Cell Environ ; 47(8): 3227-3240, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38738504

RESUMEN

Plants synthesise a vast array of volatile organic compounds (VOCs), which serve as chemical defence and communication agents in their interactions with insect herbivores. Although nitrogen (N) is a critical resource in the production of plant metabolites, its regulatory effects on defensive VOCs remain largely unknown. Here, we investigated the effect of N content in tomato (Solanum lycopersicum) on the tobacco cutworm (Spodoptera litura), a notorious agricultural pest, using biochemical and molecular experiments in combination with insect behavioural and performance analyses. We observed that on tomato leaves with different N contents, S. litura showed distinct feeding preference and growth and developmental performance. Particularly, metabolomics profiling revealed that limited N availability conferred resistance upon tomato plants to S. litura is likely associated with the biosynthesis and emission of the volatile metabolite α-humulene as a repellent. Moreover, exogenous application of α-humulene on tomato leaves elicited a significant repellent response against herbivores. Thus, our findings unravel the key factors involved in N-mediated plant defence against insect herbivores and pave the way for innovation of N management to improve the plant defence responses to facilitate pest control strategies within agroecosystems.


Asunto(s)
Herbivoria , Nitrógeno , Hojas de la Planta , Solanum lycopersicum , Spodoptera , Compuestos Orgánicos Volátiles , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiología , Solanum lycopersicum/parasitología , Animales , Nitrógeno/metabolismo , Spodoptera/fisiología , Compuestos Orgánicos Volátiles/metabolismo , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología , Defensa de la Planta contra la Herbivoria , Volatilización , Larva/fisiología
10.
Allergy ; 79(5): 1230-1241, 2024 05.
Artículo en Inglés | MEDLINE | ID: mdl-38403941

RESUMEN

BACKGROUND: Identifying predictive biomarkers for allergen immunotherapy response is crucial for enhancing clinical efficacy. This study aims to identify such biomarkers in patients with allergic rhinitis (AR) undergoing subcutaneous immunotherapy (SCIT) for house dust mite allergy. METHODS: The Tongji (discovery) cohort comprised 72 AR patients who completed 1-year SCIT follow-up. Circulating T and B cell subsets were characterized using multiplexed flow cytometry before SCIT. Serum immunoglobulin levels and combined symptom and medication score (CSMS) were assessed before and after 12-month SCIT. Responders, exhibiting ≥30% CSMS improvement, were identified. The random forest algorithm and logistic regression analysis were used to select biomarkers and establish predictive models for SCIT efficacy in the Tongji cohort, which was validated in another Wisco cohort with 43 AR patients. RESULTS: Positive SCIT response correlated with higher baseline CSMS, allergen-specific IgE (sIgE)/total IgE (tIgE) ratio, and frequencies of Type 2 helper T cells, Type 2 follicular helper T (TFH2) cells, and CD23+ nonswitched memory B (BNSM) and switched memory B (BSM) cells, as well as lower follicular regulatory T (TFR) cell frequency and TFR/TFH2 cell ratio. The random forest algorithm identified sIgE/tIgE ratio, TFR/TFH2 cell ratio, and BNSM frequency as the key biomarkers discriminating responders from nonresponders in the Tongji cohort. Logistic regression analysis confirmed the predictive value of a combination model, including sIgE/tIgE ratio, TFR/TFH2 cell ratio, and CD23+ BSM frequency (AUC = 0.899 in Tongji; validated AUC = 0.893 in Wisco). CONCLUSIONS: A T- and B-cell signature combination efficiently identified SCIT responders before treatment, enabling personalized approaches for AR patients.


Asunto(s)
Biomarcadores , Desensibilización Inmunológica , Pyroglyphidae , Rinitis Alérgica , Humanos , Rinitis Alérgica/terapia , Rinitis Alérgica/inmunología , Masculino , Desensibilización Inmunológica/métodos , Animales , Femenino , Adulto , Pyroglyphidae/inmunología , Resultado del Tratamiento , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Persona de Mediana Edad , Adulto Joven , Alérgenos/inmunología , Alérgenos/administración & dosificación , Antígenos Dermatofagoides/inmunología , Inyecciones Subcutáneas , Adolescente , Pronóstico
11.
Diabetes Metab Res Rev ; 40(1): e3706, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37545385

RESUMEN

OBJECTIVE: To explore the difference in temperature recovery following cold stimulation between participants with and without diabetes mellitus (DM). MATERIALS AND METHODS: The participants without (control group; n = 25) and with (DM group; n = 26) DM were subjected to local cold stimulation (10º C for 90 s). The thermal images of their hands were continuously captured using a thermal camera within 7 min following cold stimulation, and the highest temperature of each fingertip was calculated. According to the temperature values at different timepoints, the temperature recovery curves were drawn, and the baseline temperature (T-base), initial temperature after cooling (T0), temperature decline amplitude (T-range), and area under the temperature recovery curve > T0 (S) were calculated. Finally, symmetry differences between the two groups were analysed. RESULTS: No statistical differences in the T-base, T0, and T-range were observed between the DM and control groups. After drawing the rewarming curve according to the temperature of the fingertips of the patients following cold stimulation, the S in the DM group was significantly lower than that in the control group (p < 0.05). Furthermore, the asymmetry of the base temperature of the hand was observed in the DM group. CONCLUSIONS: Following cold stimulation, the patients with DM exhibited a different rewarming pattern than those without DM. Thus, cold stimulation tests under infrared thermography may contribute to the early screening of diabetic peripheral neuropathy in future.


Asunto(s)
Diabetes Mellitus , Termografía , Humanos , Temperatura , Termografía/métodos , Frío , Recalentamiento , Temperatura Cutánea
12.
Chemistry ; 30(9): e202303568, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38061996

RESUMEN

Selected gold complexes have been regarded as promising anti-cancer agents because they can bind with protein targets containing thiol or selenol moieties, but their clinical applications were hindered by the unbiased binding towards off-target thiol-proteins. Recently, a novel gold(III)-hydride complex (abbreviated as 1) with visible light-induced thiol reactivity has been reported as potent photo-activated anticancer agents (Angew. Chem. Int. Ed., 2020, 132, 11139). To explore new strategies to stimuli this potential antitumor drug, the effect of oriented external electric fields (OEEFs) on its geometric structure, electronic properties, and chemical reactivity was systematically investigated. Results reveal that imposing external electric fields along the Au-H bond of 1 can effectively activate this bond, which is conducive to its dissociation and the binding of Au site to potential targets. Hence, this study provides a new OEEF-strategy to activate this reported gold(III)-hydride, revealing its potential application in electrochemical therapy. We anticipate this work could promote the development of more electric field-activated anticancer agents. However, further experimental research should be conducted to verify the conclusions obtained in this work.


Asunto(s)
Antineoplásicos , Oro , Oro/química , Antineoplásicos/química , Electricidad , Compuestos de Sulfhidrilo
13.
Langmuir ; 40(31): 16538-16548, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39041610

RESUMEN

The theory of heat conduction paths has been widely recognized and widely studied in the research about the thermal conductivity of thermal conductive polymer composites at present. Encapsulating polymer pellets with thermally conductive fillers and processing them into thermally conductive polymer composites is a simple and effective method for constructing heat conduction paths. It is meaningful to investigate the related heat conduction mechanism of this method. Otherwise, this approach can significantly preserve the performance of the polymer substrate, making it highly valuable for practical material applications. In this work, polyethylene-octene elastomer (POE) pellets were encapsulated with thermal conductive fillers by physical absorption. Subsequently, the composite films containing heat conduction paths were fabricated using the encapsulated POE pellets through a heating press. Alumina (Al2O3), boron nitride (BN), and alumina/boron nitride hybrid (Al2O3/BN) fillers were used to prepare Al2O3@POE, BN@POE, and BN/Al2O3@POE composite films to investigate the influence of filler shapes on heat conduction path construction. The influence of the constitute and density of heat conduction paths on the thermal conductivity of composite films was analyzed by infrared thermal imaging, finite element analysis, and thermal resistance theory in detail. Owing to the reserved good adhesion and flexibility of the POE substrate, the composite films could be directly used as thermal interface materials for chip cooling, which presented a good heat dissipation effect. Furthermore, a series of integrated composite materials were prepared by the combination of encapsulated pellets with various functional films (copper foil, aluminum foil, and graphite sheet) through a one-pot heating press, exhibiting a good electromagnetic shielding effect. The performance of the composites and the corresponding preparation method demonstrate the strong significance of this research for practical applications.

14.
Org Biomol Chem ; 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39402895

RESUMEN

Four previously undescribed heterodimeric diketopiperazine alkaloids, expansines A-D, were identified from the solid rice medium fermented by Penicillium expansum MA147, along with one new resorcylic acid derivative and five known compounds. Their structures and relative/absolute configurations were elucidated by interpretation of their spectroscopic data, quantum chemical calculations, and chemical conversion. Some obtained compounds were evaluated for the cytotoxicity against a triple-negative breast cancer cell line MDA-MB-231, and expansine C showed an IC50 value of 3.23 µM. In further mechanistic studies, we found that it might act by increasing the expression of ATP-binding cassette transporter A1 and reducing cellular cholesterol levels, suggesting its potential as a novel anti-cancer agent.

15.
J Chem Inf Model ; 64(8): 3222-3236, 2024 04 22.
Artículo en Inglés | MEDLINE | ID: mdl-38498003

RESUMEN

Liver microsomal stability, a crucial aspect of metabolic stability, significantly impacts practical drug discovery. However, current models for predicting liver microsomal stability are based on limited molecular information from a single species. To address this limitation, we constructed the largest public database of compounds from three common species: human, rat, and mouse. Subsequently, we developed a series of classification models using both traditional descriptor-based and classic graph-based machine learning (ML) algorithms. Remarkably, the best-performing models for the three species achieved Matthews correlation coefficients (MCCs) of 0.616, 0.603, and 0.574, respectively, on the test set. Furthermore, through the construction of consensus models based on these individual models, we have demonstrated their superior predictive performance in comparison with the existing models of the same type. To explore the similarities and differences in the properties of liver microsomal stability among multispecies molecules, we conducted preliminary interpretative explorations using the Shapley additive explanations (SHAP) and atom heatmap approaches for the models and misclassified molecules. Additionally, we further investigated representative structural modifications and substructures that decrease the liver microsomal stability in different species using the matched molecule pair analysis (MMPA) method and substructure extraction techniques. The established prediction models, along with insightful interpretation information regarding liver microsomal stability, will significantly contribute to enhancing the efficiency of exploring practical drugs for development.


Asunto(s)
Inteligencia Artificial , Microsomas Hepáticos , Microsomas Hepáticos/metabolismo , Animales , Ratones , Ratas , Humanos , Aprendizaje Automático , Descubrimiento de Drogas/métodos , Preparaciones Farmacéuticas/metabolismo , Preparaciones Farmacéuticas/química
16.
Phys Chem Chem Phys ; 26(6): 5020-5026, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38258474

RESUMEN

Near-field radiative heat transfer (NFRHT) with composite materials is of significant technological interest for practical applications. In this study, we investigate the NFRHT occurring between two composite materials composed of gradient plasmonic nanoparticles (GPNs). We delve into the physical mechanism underlying NFRHT, highlighting the strong coupling and enhancement effect from surface plasmon polaritons (SPPs) at the composite/air interface or the localized SPPs (LSPPs) on the surface of nanoparticles. Furthermore, leveraging the red-shift effect caused by the gradient profile, the intensity of NFRHT can be controlled by adjusting the gradient function and volume fraction of GPNs. Notably, we observe the enhancement of NFRHT from composite materials to bulk materials, with the enhancement ratio exhibiting a notable increase at large spacing. This research establishes a theoretical foundation for the development of near-field thermal devices utilizing composite materials containing GPNs.

17.
Neuroradiology ; 66(3): 443-455, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38183426

RESUMEN

BACKGROUND: Optimal lumbar puncture segment selection remains controversial. This study aims to analyze anatomical differences among L3-4, L4-5, and L5-S1 segments across age groups and provide quantitative evidence for optimized selection. METHODS: 80 cases of CT images were collected with patients aged 10-80 years old. Threedimensional models containing L3-S1 vertebrae, dural sac, and nerve roots were reconstructed. Computer simulation determined the optimal puncture angles for the L3-4, L4-5, and L5-S1 segments. The effective dural sac area (ALDS), traversing nerve root area (ATNR), and area of the lumbar inter-laminar space (ALILS) were measured. Puncture efficacy ratio (ALDS/ALILS) and nerve injury risk ratio (ATNR/ALILS) were calculated. Cases were divided into four groups: A (10-20 years), B (21-40 years), C (41-60 years), and D (61-80 years). Statistical analysis was performed using SPSS. RESULTS: 1) ALDS was similar among segments; 2) ATNR was greatest at L5-S1; 3) ALILS was greatest at L5-S1; 4) Puncture efficacy ratio was highest at L3-4 and lowest at L5-S1; 5) Nerve injury risk was highest at L5-S1. In group D, L5-S1 ALDS was larger than L3-4 and L4-5. ALDS decreased after age 40. Age variations were minimal across parameters. CONCLUSION: The comprehensive analysis demonstrated L3-4 as the optimal first-choice segment for ages 10-60 years, conferring maximal efficacy and safety. L5-S1 can serve as an alternative option for ages 61-80 years when upper interspaces narrow. This study provides quantitative imaging evidence supporting age-specific, optimized lumbar puncture segment selection.


Asunto(s)
Vértebras Lumbares , Punción Espinal , Humanos , Niño , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Simulación por Computador , Vértebras Lumbares/diagnóstico por imagen , Región Lumbosacra , Tomografía Computarizada por Rayos X
18.
J Nat Prod ; 87(4): 743-752, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38359467

RESUMEN

Nuclear magnetic resonance (NMR) chemical shift calculations are powerful tools for structure elucidation and have been extensively employed in both natural product and synthetic chemistry. However, density functional theory (DFT) NMR chemical shift calculations are usually time-consuming, while fast data-driven methods often lack reliability, making it challenging to apply them to computationally intensive tasks with a high requirement on quality. Herein, we have constructed a 54-layer-deep graph convolutional network for 13C NMR chemical shift calculations, which achieved high accuracy with low time-cost and performed competitively with DFT NMR chemical shift calculations on structure assignment benchmarks. Our model utilizes a semiempirical method, GFN2-xTB, and is compatible with a broad variety of organic systems, including those composed of hundreds of atoms or elements ranging from H to Rn. We used this model to resolve the controversial J/K ring junction problem of maitotoxin, which is the largest whole molecule assigned by NMR calculations to date. This model has been developed into user-friendly software, providing a useful tool for routine rapid structure validation and assignation as well as a new approach to elucidate the large structures that were previously unsuitable for NMR calculations.


Asunto(s)
Teoría Funcional de la Densidad , Estructura Molecular , Espectroscopía de Resonancia Magnética con Carbono-13/métodos , Oxocinas/química , Programas Informáticos
19.
Acta Pharmacol Sin ; 45(9): 1926-1936, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38744938

RESUMEN

Primary Sjögren's syndrome (pSS) is a chronic inflammatory autoimmune disease with an unclear pathogenesis, and there is currently no approved drug for the treatment of this disease. Iguratimod, as a novel clinical anti-rheumatic drug in China and Japan, has shown remarkable efficacy in improving the symptoms of patients with pSS in clinical studies. In this study we investigated the mechanisms underlying the therapeutic effect of iguratimod in the treatment of pSS. Experimental Sjögren's syndrome (ESS) model was established in female mice by immunizing with salivary gland protein. After immunization, ESS mice were orally treated with iguratimod (10, 30, 100 mg·kg-1·d-1) or hydroxychloroquine (50 mg·kg-1·d-1) for 70 days. We showed that iguratimod administration dose-dependently increased saliva secretion, and ameliorated ESS development by predominantly inhibiting B cells activation and plasma cell differentiation. Iguratimod (30 and 100 mg·kg-1·d-1) was more effective than hydroxychloroquine (50 mg·kg-1·d-1). When the potential target of iguratimod was searched, we found that iguratimod bound to TEC kinase and promoted its degradation through the autophagy-lysosome pathway in BAFF-activated B cells, thereby directly inhibiting TEC-regulated B cells function, suggesting that the action mode of iguratimod on TEC was different from that of conventional kinase inhibitors. In addition, we found a crucial role of TEC overexpression in plasma cells of patients with pSS. Together, we demonstrate that iguratimod effectively ameliorates ESS via its unique suppression of TEC function, which will be helpful for its clinical application. Targeting TEC kinase, a new regulatory factor for B cells, may be a promising therapeutic option.


Asunto(s)
Diferenciación Celular , Cromonas , Células Plasmáticas , Proteínas Tirosina Quinasas , Síndrome de Sjögren , Sulfonamidas , Animales , Síndrome de Sjögren/tratamiento farmacológico , Femenino , Diferenciación Celular/efectos de los fármacos , Ratones , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Tirosina Quinasas/metabolismo , Células Plasmáticas/efectos de los fármacos , Cromonas/farmacología , Cromonas/uso terapéutico , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico , Benzofuranos/farmacología , Benzofuranos/uso terapéutico , Hidroxicloroquina/farmacología , Hidroxicloroquina/uso terapéutico , Modelos Animales de Enfermedad , Humanos , Linfocitos B/efectos de los fármacos , Linfocitos B/metabolismo , Antirreumáticos/farmacología , Antirreumáticos/uso terapéutico
20.
Acta Pharmacol Sin ; 2024 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-39472494

RESUMEN

Translational pharmacological research on traditional medicines lays the foundation for precisely understanding how the medicines function in the body to deliver therapeutic benefits. Borneolum syntheticum (Bingpian) is commonly used in Chinese herbal medicines for coronary heart disease, but its specific cardiovascular impact remains poorly understood. Isoborneol, a constituent of Bingpian, has been found to reduce lipid accumulation in macrophages in vitro, but its oral bioavailability is limited. This investigation aimed to evaluate anti-atherosclerotic effects of Bingpian, based on understanding its first-pass metabolism. Human subjects orally received an herbal medicine containing Bingpian and their plasma samples were analyzed to identify the major circulating compounds of Bingpian, with the metabolism that was also characterized in vitro and in mice. The identified compounds were evaluated for their ability to inhibit macrophage foam-cell formation induced by oxidized low-density lipoprotein. Furthermore, the anti-atherosclerotic effect of repeatedly dosed Bingpian was assessed in ApoE-/- mice fed a high-fat diet. In human subjects, the major circulating compounds of Bingpian were metabolites, rather than their precursor constituents borneol and isoborneol. These constituents were efficiently absorbed in the intestinal tract but underwent significant first-pass metabolism, involving UGT2B7-mediated glucuronidation into borneol-2-O-glucuronide and isoborneol-2-O-glucuronide, respectively, and CYP2A6/2B6/3A-mediated oxidation both into camphor. Despite their poor membrane permeability, hepatic efflux of borneol-2-O-glucuronide and isoborneol-2-O-glucuronide into the systemic circulation was enhanced by MRP3/4. The circulating metabolites, particularly their combinations, markedly inhibited macrophage foam-cell formation induced by oxidized low-density lipoprotein in vitro. Sub-chronic administration of Bingpian (30 mg·kg-1·d-1, i.g.) for 12 weeks significantly decreased atherosclerotic lesion size and enhanced plaque stability in ApoE-/- mice. Systemic exposure to Bingpian metabolites in mice closely resembles that in humans, suggesting that the pharmacodynamic effects of Bingpian in mice are likely applicable to humans. Overall, the cardiovascular benefits of Bingpian involve reducing atherosclerosis by inhibiting foam-cell formation through its metabolites. This investigation supports that oral Bingpian could be a druggable agent for reducing atherosclerosis.

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