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1.
Cell ; 185(12): 2035-2056.e33, 2022 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-35688132

RESUMEN

Alpha-synuclein (αS) is a conformationally plastic protein that reversibly binds to cellular membranes. It aggregates and is genetically linked to Parkinson's disease (PD). Here, we show that αS directly modulates processing bodies (P-bodies), membraneless organelles that function in mRNA turnover and storage. The N terminus of αS, but not other synucleins, dictates mutually exclusive binding either to cellular membranes or to P-bodies in the cytosol. αS associates with multiple decapping proteins in close proximity on the Edc4 scaffold. As αS pathologically accumulates, aberrant interaction with Edc4 occurs at the expense of physiologic decapping-module interactions. mRNA decay kinetics within PD-relevant pathways are correspondingly disrupted in PD patient neurons and brain. Genetic modulation of P-body components alters αS toxicity, and human genetic analysis lends support to the disease-relevance of these interactions. Beyond revealing an unexpected aspect of αS function and pathology, our data highlight the versatility of conformationally plastic proteins with high intrinsic disorder.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Humanos , Enfermedad de Parkinson/metabolismo , Cuerpos de Procesamiento , Estabilidad del ARN , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
2.
Cell ; 184(2): 370-383.e13, 2021 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-33333023

RESUMEN

Proton-coupled monocarboxylate transporters MCT1-4 catalyze the transmembrane movement of metabolically essential monocarboxylates and have been targeted for cancer treatment because of their enhanced expression in various tumors. Here, we report five cryo-EM structures, at resolutions of 3.0-3.3 Å, of human MCT1 bound to lactate or inhibitors in the presence of Basigin-2, a single transmembrane segment (TM)-containing chaperon. MCT1 exhibits similar outward-open conformations when complexed with lactate or the inhibitors BAY-8002 and AZD3965. In the presence of the inhibitor 7ACC2 or with the neutralization of the proton-coupling residue Asp309 by Asn, similar inward-open structures were captured. Complemented by structural-guided biochemical analyses, our studies reveal the substrate binding and transport mechanism of MCTs, elucidate the mode of action of three anti-cancer drug candidates, and identify the determinants for subtype-specific sensitivities to AZD3965 by MCT1 and MCT4. These findings lay out an important framework for structure-guided drug discovery targeting MCTs.


Asunto(s)
Antineoplásicos/farmacología , Transportadores de Ácidos Monocarboxílicos/antagonistas & inhibidores , Transportadores de Ácidos Monocarboxílicos/química , Simportadores/antagonistas & inhibidores , Simportadores/química , Secuencia de Aminoácidos , Animales , Basigina/química , Sitios de Unión , Microscopía por Crioelectrón , Humanos , Ligandos , Modelos Moleculares , Transportadores de Ácidos Monocarboxílicos/ultraestructura , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Protones , Pirimidinonas/química , Pirimidinonas/farmacología , Ratas , Homología Estructural de Proteína , Especificidad por Sustrato , Simportadores/ultraestructura , Tiofenos/química , Tiofenos/farmacología
3.
Cell ; 183(1): 258-268.e12, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32860739

RESUMEN

Plasmodium species, the causative agent of malaria, rely on glucose for energy supply during blood stage. Inhibition of glucose uptake thus represents a potential strategy for the development of antimalarial drugs. Here, we present the crystal structures of PfHT1, the sole hexose transporter in the genome of Plasmodium species, at resolutions of 2.6 Å in complex with D-glucose and 3.7 Å with a moderately selective inhibitor, C3361. Although both structures exhibit occluded conformations, binding of C3361 induces marked rearrangements that result in an additional pocket. This inhibitor-binding-induced pocket presents an opportunity for the rational design of PfHT1-specific inhibitors. Among our designed C3361 derivatives, several exhibited improved inhibition of PfHT1 and cellular potency against P. falciparum, with excellent selectivity to human GLUT1. These findings serve as a proof of concept for the development of the next-generation antimalarial chemotherapeutics by simultaneously targeting the orthosteric and allosteric sites of PfHT1.


Asunto(s)
Proteínas de Transporte de Monosacáridos/ultraestructura , Plasmodium falciparum/metabolismo , Plasmodium falciparum/ultraestructura , Proteínas Protozoarias/ultraestructura , Secuencia de Aminoácidos , Animales , Antimaláricos , Transporte Biológico , Glucosa/metabolismo , Humanos , Malaria , Malaria Falciparum/parasitología , Proteínas de Transporte de Monosacáridos/química , Proteínas de Transporte de Monosacáridos/metabolismo , Parásitos , Plasmodium falciparum/genética , Proteínas Protozoarias/química , Proteínas Protozoarias/metabolismo , Azúcares/metabolismo
4.
Nature ; 2024 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-39401516

RESUMEN

In recent years, perovskite has been widely adopted in series-connected monolithic tandem solar cells (TSCs) to overcome the Shockley-Queisser limit of single-junction solar cells. Perovskite/organic TSCs, comprising a wide-bandgap (WBG) perovskite solar cell (pero-SC) as the front cell and a narrow-bandgap organic solar cell (OSC) as the rear cell, have recently drawn attention owing to the good stability and potential high power conversion efficiency (PCE)1,2,3,4. However, WBG pero-SCs usually exhibit higher voltage losses than regular pero-SCs, which limits the performance of TSCs5,6. One of the major obstacles comes from interfacial recombination at the perovskite/C60 interface, and it is important to develop effective surface passivation strategies to pursue higher PCE of perovskite/organic TSCs7. Here we exploit a new surface passivator cyclohexane 1,4-diammonium diiodide (CyDAI2), which naturally contains two isomeric structures with ammonium groups on the same or opposite sides of the hexane ring (denoted as cis-CyDAI2 and trans-CyDAI2, respectively), and the two isomers demonstrate completely different surface interaction behaviors. The cis-CyDAI2 passivation treatment reduces the Quasi-Fermi level splitting (QFLS)-open circuit voltage (Voc) mismatch of the WBG pero-SCs with a bandgap of 1.88 eV and enhanced its Voc to 1.36 V. Combining the cis-CyDAI2 treated perovskite and the organic active layer with a narrow-bandgap of 1.24 eV, the constructed monolithic perovskite/organic TSC demonstrates a PCE of 26.4% (certified as 25.7%).

5.
Proc Natl Acad Sci U S A ; 121(20): e2312855121, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38713626

RESUMEN

The immune landscape of bladder cancer progression is not fully understood, and effective therapies are lacking in advanced bladder cancer. Here, we visualized that bladder cancer cells recruited neutrophils by secreting interleukin-8 (IL-8); in turn, neutrophils played dual functions in bladder cancer, including hepatocyte growth factor (HGF) release and CCL3highPD-L1high super-immunosuppressive subset formation. Mechanistically, c-Fos was identified as the mediator of HGF up-regulating IL-8 transcription in bladder cancer cells, which was central to the positive feedback of neutrophil recruitment. Clinically, compared with serum IL-8, urine IL-8 was a better biomarker for bladder cancer prognosis and clinical benefit of immune checkpoint blockade (ICB). Additionally, targeting neutrophils or hepatocyte growth factor receptor (MET) signaling combined with ICB inhibited bladder cancer progression and boosted the antitumor effect of CD8+ T cells in mice. These findings reveal the mechanism by which tumor-neutrophil cross talk orchestrates the bladder cancer microenvironment and provide combination strategies, which may have broad impacts on patients suffering from malignancies enriched with neutrophils.


Asunto(s)
Progresión de la Enfermedad , Interleucina-8 , Neutrófilos , Microambiente Tumoral , Neoplasias de la Vejiga Urinaria , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/inmunología , Microambiente Tumoral/inmunología , Humanos , Neutrófilos/inmunología , Neutrófilos/metabolismo , Animales , Ratones , Interleucina-8/metabolismo , Línea Celular Tumoral , Factor de Crecimiento de Hepatocito/metabolismo , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Antígeno B7-H1/metabolismo , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Femenino , Masculino , Infiltración Neutrófila
6.
Plant Physiol ; 195(2): 1642-1659, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38431524

RESUMEN

Maize (Zea mays) smut is a common biotrophic fungal disease caused by Ustilago maydis and leads to low maize yield. Maize resistance to U. maydis is a quantitative trait. However, the molecular mechanism underlying the resistance of maize to U. maydis is poorly understood. Here, we reported that a maize mutant caused by a single gene mutation exhibited defects in both fungal resistance and plant development. maize mutant highly susceptible to U. maydis (mmsu) with a dwarf phenotype forms tumors in the ear. A map-based cloning and allelism test demonstrated that 1 gene encoding a putative arogenate dehydratase/prephenate dehydratase (ADT/PDT) is responsible for the phenotypes of the mmsu and was designated as ZmADT2. Combined transcriptomic and metabolomic analyses revealed that mmsu had substantial differences in multiple metabolic pathways in response to U. maydis infection compared with the wild type. Disruption of ZmADT2 caused damage to the chloroplast ultrastructure and function, metabolic flux redirection, and reduced the amounts of salicylic acid (SA) and lignin, leading to susceptibility to U. maydis and dwarf phenotype. These results suggested that ZmADT2 is required for maintaining metabolic flux, as well as resistance to U. maydis and plant development in maize. Meanwhile, our findings provided insights into the maize response mechanism to U. maydis infection.


Asunto(s)
Resistencia a la Enfermedad , Hidroliasas , Enfermedades de las Plantas , Zea mays , Basidiomycota/fisiología , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas , Hidroliasas/genética , Hidroliasas/metabolismo , Mutación/genética , Fenotipo , Enfermedades de las Plantas/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Salicílico/metabolismo , Ustilago/genética , Zea mays/microbiología , Zea mays/genética , Zea mays/crecimiento & desarrollo
7.
Proc Natl Acad Sci U S A ; 119(49): e2123487119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36454749

RESUMEN

Hexanucleotide G4C2 repeat expansions in the C9orf72 gene are the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Dipeptide repeat proteins (DPRs) generated by translation of repeat-containing RNAs show toxic effects in vivo as well as in vitro and are key targets for therapeutic intervention. We generated human antibodies that bind DPRs with high affinity and specificity. Anti-GA antibodies engaged extra- and intra-cellular poly-GA and reduced aggregate formation in a poly-GA overexpressing human cell line. However, antibody treatment in human neuronal cultures synthesizing exogenous poly-GA resulted in the formation of large extracellular immune complexes and did not affect accumulation of intracellular poly-GA aggregates. Treatment with antibodies was also shown to directly alter the morphological and biochemical properties of poly-GA and to shift poly-GA/antibody complexes to more rapidly sedimenting ones. These alterations were not observed with poly-GP and have important implications for accurate measurement of poly-GA levels including the need to evaluate all centrifugation fractions and disrupt the interaction between treatment antibodies and poly-GA by denaturation. Targeting poly-GA and poly-GP in two mouse models expressing G4C2 repeats by systemic antibody delivery for up to 16 mo was well-tolerated and led to measurable brain penetration of antibodies. Long-term treatment with anti-GA antibodies produced improvement in an open-field movement test in aged C9orf72450 mice. However, chronic administration of anti-GA antibodies in AAV-(G4C2)149 mice was associated with increased levels of poly-GA detected by immunoassay and did not significantly reduce poly-GA aggregates or alleviate disease progression in this model.


Asunto(s)
Genes Reguladores , Poli A , Animales , Humanos , Ratones , Complejo Antígeno-Anticuerpo , Proteína C9orf72/genética , Dipéptidos , Modelos Animales de Enfermedad
8.
J Cell Mol Med ; 28(19): e70073, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39397259

RESUMEN

Human papillomavirus (HPV) infection is a causative factor in the occurrence and progression of oropharyngeal squamous cell carcinoma (OPSCC). In recent years, clinical studies have found that HPV-positive OPSCC patients may present a better prognosis than HPV-negative patients, yet the underlying causes are unclear. This study aimed to investigate the relevance of HPV infection and the prognosis of OPSCC. On this basis, we aimed to establish a prediction model to accurately predict the prognosis and guide clinical practice. We analysed the records of 233 patients with OPSCC. Cox regression was applied to identify factors associated with survival. Moreover, variables with significant discrepancies were integrated into a nomogram model to predict prognosis. The results showed that HPV was an independent prognostic factor for OS and PFS. Immunoglobulin Heavy Constant Mu (IGHM) mRNA was significantly upregulated in patients with HPV-positive OPSCC. Crucially, IGHM expression was associated with better prognosis. The receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis both confirmed that the prognostic model exhibits good performance. In summary, HPV infection were independent prognostic factors for OPSCC. IGHM may be the key contributors to the prognostic differences in HPV-associated OPSCC. This nomogram model was able to accurately predict the prognosis of patients.


Asunto(s)
Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Humanos , Masculino , Femenino , Neoplasias Orofaríngeas/virología , Neoplasias Orofaríngeas/mortalidad , Neoplasias Orofaríngeas/genética , Pronóstico , Persona de Mediana Edad , Infecciones por Papillomavirus/virología , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética , Nomogramas , Curva ROC , Papillomaviridae/genética , Anciano , Carcinoma de Células Escamosas/virología , Carcinoma de Células Escamosas/genética , Biomarcadores de Tumor/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Virus del Papiloma Humano
9.
J Cell Physiol ; 239(2): e31149, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38308838

RESUMEN

Metabolic disorders and oxidative stress are the main causes of diabetic cardiomyopathy. Activation of nuclear factor erythroid 2-related factor 2 (Nrf2) exerts a powerful antioxidant effect and prevents the progression of diabetic cardiomyopathy. However, the mechanism of its cardiac protection and direct action on cardiomyocytes are not well understood. Here, we investigated in a cardiomyocyte-restricted Nrf2 transgenic mice (Nrf2-TG) the direct effect of Nrf2 on cardiomyocytes in DCM and its mechanism. In this study, cardiomyocyte-restricted Nrf2 transgenic mice (Nrf2-TG) were used to directly observe whether cardiomyocyte-specific overexpression of Nrf2 can prevent diabetic cardiomyopathy and correct glucose and lipid metabolism disorders in the heart. Compared to wild-type mice, Nrf2-TG mice showed resistance to diabetic cardiomyopathy in a streptozotocin-induced type 1 diabetes mouse model. This was primarily manifested as improved echocardiography results as well as reduced myocardial fibrosis, cardiac inflammation, and oxidative stress. These results showed that Nrf2 can directly act on cardiomyocytes to exert a cardioprotective role. Mechanistically, the cardioprotective effects of Nrf2 depend on its antioxidation activity, partially through improving glucose and lipid metabolism by directly targeting lipid metabolic pathway of AMPK/Sirt1/PGC-1α activation via upstream genes of sestrin2 and LKB1, and indirectly enabling AKT/GSK-3ß/HK-Ⅱ activity via AMPK mediated p70S6K inhibition.


Asunto(s)
Diabetes Mellitus Experimental , Cardiomiopatías Diabéticas , Ratones , Animales , Cardiomiopatías Diabéticas/genética , Cardiomiopatías Diabéticas/prevención & control , Cardiomiopatías Diabéticas/metabolismo , Antioxidantes/farmacología , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Glucosa/metabolismo , Proteínas Quinasas Activadas por AMP/metabolismo , Metabolismo de los Lípidos/genética , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Transducción de Señal , Diabetes Mellitus Experimental/metabolismo , Miocitos Cardíacos/metabolismo , Estrés Oxidativo , Ratones Transgénicos
10.
J Am Chem Soc ; 146(6): 4162-4171, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38306246

RESUMEN

Magnesium is an abundant metal element in space, and magnesium chemistry has vital importance in the evolution of interstellar medium (ISM) and circumstellar regions, such as the asymptotic giant branch star IRC+10216 where a variety of Mg compounds bearing H, C, N, and O have been detected and proposed as the important components in the gas-phase molecular clouds and solid-state dust grains. Herein, we report the formation and infrared spectroscopic characterization of the Mg-bearing molecules HMg, [Mg, N, C], [Mg, H, N, C], [Mg, N, C, O], and [Mg, H, N, C, O] from the reactions of Mg/Mg+ and the prebiotic isocyanic acid (HNCO) in the solid neon matrix. Based on their thermal diffusion and photochemical behavior, a complex reactivity landscape involving association, decomposition, and isomerization reactions of these Mg-bearing molecules is developed, which can not only help understand the chemical processes of the magnesium (iso)cyanides in astrochemistry but also provide implications on the presence of magnesium (iso)cyanates in the ISM and the chemical model for the dust grain surface reactions. It also provides a new paradigm of the key intermediate nature of the cationic complexes in the formation of neutral interstellar species.

11.
Eur J Neurosci ; 59(10): 2535-2548, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38720367

RESUMEN

The maturation of forebrain dopamine circuitry occurs over multiple developmental periods, extending from early postnatal life until adulthood, with the precise timing of maturation defined by the target region. We recently demonstrated in the adult mouse brain that axon terminals arising from midbrain dopamine neurons innervate the anterior corpus callosum and that oligodendrocyte lineage cells in this white matter tract express dopamine receptor transcripts. Whether corpus callosal dopamine circuitry undergoes maturational changes between early adolescence and adulthood is unknown but may be relevant to understanding the dramatic micro- and macro-anatomical changes that occur in the corpus callosum of multiple species during early adolescence, including in the degree of myelination. Using quantitative neuroanatomy, we show that dopamine innervation in the forceps minor, but not the rostral genu, of the corpus callosum, is greater during early adolescence (P21) compared to adulthood (>P90) in wild-type mice. We further demonstrate with RNAscope that, as in the adult, Drd1 and Drd2 transcripts are expressed at higher levels in oligodendrocyte precursor cells (OPCs) and decline as these cells differentiate into oligodendrocytes. In addition, the number of OPCs that express Drd1 transcripts during early adolescence is double the number of those expressing the transcript during early adulthood. These data further implicate dopamine in axon myelination and myelin regulation. Moreover, because developmental (activity-independent) myelination peaks during early adolescence, with experience-dependent (activity-dependent) myelination greatest during early adulthood, our data suggest that potential roles of dopamine on callosal myelination shift between early adolescence and adulthood, from a developmental role to an experience-dependent role.


Asunto(s)
Cuerpo Calloso , Ratones Endogámicos C57BL , Receptores de Dopamina D1 , Receptores de Dopamina D2 , Animales , Ratones , Cuerpo Calloso/metabolismo , Cuerpo Calloso/crecimiento & desarrollo , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D2/genética , Masculino , Neuronas Dopaminérgicas/metabolismo , Dopamina/metabolismo , Células Precursoras de Oligodendrocitos/metabolismo , Femenino
12.
Anal Chem ; 96(37): 15042-15049, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39219053

RESUMEN

Despite many luminescent advantages including outstanding absorption coefficient and high quantum yield, pyrene and its derivatives have been suffering from a dramatic aggregation-caused quenching (ACQ) effect. Although the dramatic ACQ effect of pyrene-based fluorophores has been restrained in pyrene-doped metal-organic frameworks (MOFs), the low loading of fluorescent (FL) units substantially impedes the improved luminescent behaviors. Herein, pyrene-based MOFs hydrogel was synthesized with a high loading of pyrene as the unique organic linker blocks instead of a dopant in MOFs. The gel matrix contributed to rigidifying the location of the FL emitters and achieving intensive FL emission and high luminescent stability and therefore efficiently overcoming the ACQ effect. Furthermore, the protonation of pyrene in the MOFs hydrogel remarkably decreased the luminescent intensity, which endowed the FL hydrogel with highly pH-responsive activity in the broad range (pH 4-10). Interestingly, glucose oxidase was immobilized into ZIF-8 as a highly efficient luminescent quencher, which contributed to catalyzing the form of gluconic acid and thus drastically quenching the FL signal of the MOFs hydrogel. Furthermore, the emitter-quencher pair of pyrene-based MOFs hydrogel and glucose oxidase was successfully employed to develop an ultrasensitive FL immunoassay platform for cardiac troponin I (as a model analyte). The limit of detection for cardiac troponin I was 5.2 pg/mL (3σ). The proof-of-principle study demonstrated the thrilling auxiliary effect of tailorable MOFs hydrogel on boosting the feasibility of aqueous insoluble FL chromophores for trace analysis.


Asunto(s)
Hidrogeles , Estructuras Metalorgánicas , Pirenos , Troponina I , Pirenos/química , Estructuras Metalorgánicas/química , Troponina I/análisis , Troponina I/sangre , Concentración de Iones de Hidrógeno , Humanos , Hidrogeles/química , Inmunoensayo/métodos , Colorantes Fluorescentes/química , Fluorescencia
13.
Anal Chem ; 96(4): 1742-1749, 2024 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-38221770

RESUMEN

Speciation analysis of arsenic in urine is essential for the studies of arsenic metabolism and biological effects, but the unstable arsenic species represented by MMAIII and DMAIII pose a huge challenge to analytical accuracy. Herein, a novel urine self-sampling (USS) kit combined with an automated preparation-sampler (APS) device is rationally designed and used for convenient analysis of arsenic metabolites by high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS). The subject can collect urine into a sampling vial at home and use a homemade syringe to pump argon to displace oxygen in the vial, thereby inhibiting the oxidation of MMAIII and DMAIII. After USS and transportation, the sampling vial is loaded directly onto the APS device, where the urine sample can be automatically mixed with diluent, filtered, and loaded into HPLC-ICPMS for arsenic speciation analysis under anaerobic conditions. For a single sample, the sampling time and the analysis time are <8 and <18 min, respectively. The recoveries of MMAIII and DMAIII in urine over 24 h at 4 °C are 86 and 67%, surpassing the conventional sampling method by 28 and 67%, respectively. When the APS is coupled to HPLC-ICPMS, the detection limits of AsC, iAsIII, MMAIII, DMAV, MMAV, DMAIII, and iAsV are 0.03-0.10 µg L-1 with precisions of <10%. The present method provides a convenient and reliable tool for the storage and analysis of unstable arsenic species in urine and lays the foundation for studying the metabolic and biological effects of methylated trivalent arsenicals.


Asunto(s)
Arsénico , Arsenicales , Compuestos Organometálicos , Arsénico/análisis , Arsenicales/análisis , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas/métodos
14.
Anal Chem ; 96(18): 7155-7162, 2024 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-38652710

RESUMEN

Microplastics (MPs) can act as carriers of environmental arsenic species into the stomach with food and release arsenic species during digestion, which threatens human health. Herein, an integrated dynamic stomach model (DSM)-capillary electrophoresis-inductively coupled plasma mass spectrometry (CE-ICPMS) is developed for online monitoring of the release and transformation behaviors of arsenic species loaded on MPs (As-MPs) in the simulated human stomach. The 3D-printed DSM with a soft stomach chamber enables the behaviors of gastric peristalsis, gastric and salivary fluid addition, pH adjustment, and gastric emptying (GE) to be controlled by a self-written program after oral ingestion of food with As-MPs. The gastric extract during digestion is introduced into the spiral channel to remove the large particulate impurity and online filtered to obtain the clarified arsenic-containing solution for subsequent speciation analysis of arsenic by CE-ICPMS. The digestion conditions and pretreatment processes of DSM are tracked and validated, and the release rates of As-MPs digested by DSM are compared with those digested by the static stomach model and DSM without GE. The release rate of inorganic arsenic on MPs is higher than that of organic arsenic throughout the gastric digestion process, and 8% of As(V) is reduced to As(III). The detection limits for As(III), DMA, MMA, and As(V) are 0.5-0.9 µg L-1 using DSM-CE-ICPMS, along with precisions of ≤8%. This present method provides an integrated and convenient tool for evaluating the release and transformation of As-MPs during human gastric digestion and provides a reference for exploring the interactions between MPs and metals/metalloids in the human body.


Asunto(s)
Arsénico , Electroforesis Capilar , Espectrometría de Masas , Microplásticos , Estómago , Arsénico/análisis , Humanos , Espectrometría de Masas/métodos , Electroforesis Capilar/métodos , Microplásticos/análisis , Estómago/química , Digestión , Modelos Biológicos
15.
Eur J Immunol ; 53(10): e2250071, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37379419

RESUMEN

Disulfide bond A oxidoreductase-like protein (DsbA-L) drives acute kidney injury (AKI) by directly upregulating the expression of voltage-dependent anion-selective channels in proximal tubular cells. However, the role of DsbA-L in immune cells remains unclear. In this study, we used an LPS-induced AKI mouse model to assess the hypothesis that DsbA-L deletion attenuates LPS-induced AKI and explore the potential mechanism of DsbA-L action. After 24 hours of LPS exposure, the DsbA-L knockout group exhibited lower serum creatinine levels compared to the WT group. Furthermore, peripheral levels of the inflammatory cytokine IL-6 were decreased. Transcriptomic data analysis revealed a significant down-regulation in the IL-17 and tumor necrosis factor pathways in DsbA-L knockout mice following LPS induction. Metabolomic analysis suggested that arginine metabolism was significantly different between the WT and DsbA-L knockout groups after LPS treatment. Notably, the M1 polarization of macrophages in the kidneys of DsbA-L knockout AKI mice was significantly reduced. Expression of the transcription factors NF-κB and AP-1 was downregulated after DsbA-L knockout. Our results suggest that DsbA-L regulates LPS-mediated oxidative stress, promotes M1 polarization of macrophages, and induces expression of inflammatory factors via the NF-κB/AP-1 pathway.


Asunto(s)
Lesión Renal Aguda , FN-kappa B , Animales , Ratones , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/genética , Riñón/patología , Lipopolisacáridos/farmacología , Macrófagos , FN-kappa B/metabolismo , Factor de Transcripción AP-1
16.
Artículo en Inglés | MEDLINE | ID: mdl-39489842

RESUMEN

OBJECTIVE: To quantify the pressure levels necessary for effective Manual Lymphatic Drainage (MLD) in managing Breast Cancer-Related Lymphedema (BCRL) across various stages, and to contribute to the development of standardized protocols for MLD therapy. METHODS: The study included 42 patients with BCRL (Stages I-III) and 14 certified lymphedema therapists. Forearms and upper arm circumferences were measured pre and post a 21-day MLD intervention. A tactile sensor system recorded the applied pressure during treatment. The data were preprocessed and statistically analyzed to assess pressure patterns and their stage-specific impacts on lymphedema. RESULTS: The mean age of the patients was 52.4 years, and that of the therapists was 39.1 years. A statistically significant reduction in arm circumference was observed post-MLD treatment (P < 0.05). The pressure applied varied across stages: I forearm 16.5-20.1 mmHg, I upper arm 16.1-20.7 mmHg; II forearm 16.6-19.8 mmHg, II upper arm 19.7-23.8 mmHg; III forearm 29.3-34.3 mmHg, III upper arm 29.7-34.3 mmHg. No statistically significant difference was found between forearm and upper arm treatment pressures within Stages I (P = 0.283) and III (P = 0.08), while Stage II exhibited a significant difference (P < 0.001). Across the same treatment area, pressures for Stages I and II in the forearm were significantly lower than those in Stage III (P < 0.001). The treatment pressure differences between forearm stages I and II were not statistically significant (P > 0.05). Differences in upper arm treatment pressures across Stages I, II, and III were also statistically significant (P < 0.001). DISCUSSION: The study provides quantitative evidence on the pressure ranges needed for MLD across different stages of BCRL. It highlights the importance for stage-specific pressure adjustments to optimize treatment outcomes. These findings contribute to the existing body of knowledge on MLD and offer valuable data that could inform the development of rehabilitation technologies, including intelligent robots and visualization systems, as well as enhance therapist training programs.

17.
Small ; : e2400798, 2024 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-39340271

RESUMEN

Diamond nanomaterials are renowned for their exceptional properties, which include the inherent attributes of bulk diamond. Additionally, they exhibit unique characteristics at the nanoscale, including high specific surface areas, tunable surface structure, and excellent biocompatibility. These multifaceted attributes have piqued the interest of researchers globally, leading to an extensive exploration of various diamond nanostructures in a myriad of applications. This review focuses on non-zero-dimensional (non-0D) diamond nanostructures including diamond films and extended diamond nanostructures, such as diamond nanowires, nanoplatelets, and diamond foams. It delves into the fabrication, modification, and diverse applications of non-0D diamond nanostructures. This review begins with a concise review of the preparation methods for different types of diamond films and extended nanostructures, followed by an exploration of the intricacies of surface termination and the process of immobilizing target moieties of interest. It then transitions into an exploration of the applications of diamond films and extended nanostructures in the fields of biomedicine and electrochemistry. In the concluding section, this article provides a forward-looking perspective on the current state and future directions of diamond films and extended nanostructures research, offering insights into the opportunities and challenges that lie ahead in this exciting field.

18.
Small ; 20(28): e2310523, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38295042

RESUMEN

Electrochemical capacitors (ECs) show great perspective in alternate current (AC) filtering once they simultaneously reach ultra-fast response and high capacitance density. Nevertheless, the structure-design criteria of the two key properties are often mutually incompatible in electrode construction. Herein, it is proposed that combining vertically oriented porous carbon with enhanced interfacial capacitance (Ci) can efficiently solve this issue. Theoretically, the density function theory calculation shows that the Ci of a carbon electrode can be enhanced by boron doping due to the corresponding compact induced charge layer. Experimentally, the vertical-oriented boron-doped graphene nanowalls (BGNWs) electrodes, whose Ci is enhanced from 4.20 to 10.16 µF cm-2 upon boron doping, are prepared on a large scale (480 cm2) using a hot-filament chemical vapor deposition technique (HFCVD). Owing to the high Ci and vertically oriented porous structure, BGNWs-based EC has a high capacitance density of 996 µF cm-2 with a phase angle of - 79.4° at 120 Hz in aqueous electrolyte and a high energy density of 1953 µFV2 cm-2 in organic electrolyte. As a result, the EC is capable of smoothing 120 Hz ripples for 60 Hz AC filtering. These results provide enlightening insights on designing high-performance ECs for high-frequency applications.

19.
Small ; : e2403970, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38984738

RESUMEN

Self-assembly of nanoparticles into supercrystals represents a powerful approach to create unique and complex superstructures with fascinating properties and novel functions, but the complexity in spatial configuration, and the tunability in lattice structure are still quite limited compared to the crystals formed by atoms and molecules. Herein, shallowly concave gold nanoarrows with a unique concave-convex geometry are synthesized and employed as novel building blocks for shape-directed self-assembly of a wealth of complex 3D supercrystals with unprecedented configurations. The obtained diverse superstructures including six Interlocking-type supercrystals and three Packing-type supercrystals exhibit four types of Bravais lattices (i.e., tP, oI, tI, and oF) and six types of crystallographic space groups (i.e., Pmmm, I222, Pnnm, Ibam, I4/mmm, and Fmmm), which have not been documented in the mesoscale self-assembled systems. It has been revealed that the relative yield of different supercrystal structures is mainly determined by the packing density and deformability of the supercrystals, which are closely related to the tailored concavity of the nanoparticles and is affected by the particle concentration, thus allowing for programmable self-assembly into specific supercrystals through particle shape modulation. The concavity-enabled supercrystal engineering may open a new avenue toward unconventional nanoparticle superstructures with expanded complexity, tunability, and functionality.

20.
Planta ; 259(2): 50, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38285114

RESUMEN

MAIN CONCLUSION: The oxidosqualene cyclases (OSCs) generating triterpenoid skeletons in Cyclocarya paliurus were identified for the first time, and two uridine diphosphate (UDP)-glycosyltransferases (UGTs) catalyzing the glycosylation of flavonoids were characterized. Cyclocarya paliurus, a native rare dicotyledonous plant in China, contains an abundance of triterpenoid saponins and flavonoid glycosides that exhibit valuable pharmaceutical effects in preventing hypertension, hyperlipidemia, and diabetes. However, the molecular mechanism explaining the biosynthesis of triterpenoid saponin and flavonoid glycoside in C. paliurus remains unclear. In this study, the triterpene content in different tissues and the expression pattern of genes encoding the key enzymes associated with triterpenoid saponin and flavonoid glycoside biosynthesis were studied using transcriptome and metabolome analysis. The eight upstream oxidosqualene cyclases (OSCs) involved in triterpenoid saponin biosynthesis were functionally characterized, among them CpalOSC6 catalyzed 2,3;22,23-dioxidosqualene to form 3-epicabraleadiol; CpalOSC8 cyclized 2,3-oxidosqualene to generate dammarenediol-II; CpalOSC2 and CpalOSC3 produced ß-amyrin and CpalOSC4 produced cycloartenol, while CpalOSC2-CpalOSC5, CpalOSC7, and CpalOSC8 all produced lanosterol. However, no catalytic product was detected for CpalOSC1. Moreover, two downstream flavonoid uridine diphosphate (UDP)-glycosyltransferases (UGTs) (CpalUGT015 and CpalUGT100) that catalyze the last step of flavonoid glycoside biosynthesis were functionally elucidated. These results uncovered the key genes involved in the biosynthesis of triterpenoid saponins and flavonoid glycosides in C. paliurus that could be applied to produce flavonoid glycosides and key triterpenoid saponins in the future via a synthetic strategy.


Asunto(s)
Saponinas , Escualeno/análogos & derivados , Triterpenos , Glicósidos , Flavonoides , Saponinas/genética , Glicosiltransferasas , Uridina Difosfato
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