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1.
Nature ; 626(7998): 419-426, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38052229

RESUMEN

Determining the structure and phenotypic context of molecules detected in untargeted metabolomics experiments remains challenging. Here we present reverse metabolomics as a discovery strategy, whereby tandem mass spectrometry spectra acquired from newly synthesized compounds are searched for in public metabolomics datasets to uncover phenotypic associations. To demonstrate the concept, we broadly synthesized and explored multiple classes of metabolites in humans, including N-acyl amides, fatty acid esters of hydroxy fatty acids, bile acid esters and conjugated bile acids. Using repository-scale analysis1,2, we discovered that some conjugated bile acids are associated with inflammatory bowel disease (IBD). Validation using four distinct human IBD cohorts showed that cholic acids conjugated to Glu, Ile/Leu, Phe, Thr, Trp or Tyr are increased in Crohn's disease. Several of these compounds and related structures affected pathways associated with IBD, such as interferon-γ production in CD4+ T cells3 and agonism of the pregnane X receptor4. Culture of bacteria belonging to the Bifidobacterium, Clostridium and Enterococcus genera produced these bile amidates. Because searching repositories with tandem mass spectrometry spectra has only recently become possible, this reverse metabolomics approach can now be used as a general strategy to discover other molecules from human and animal ecosystems.


Asunto(s)
Amidas , Ácidos y Sales Biliares , Ésteres , Ácidos Grasos , Metabolómica , Animales , Humanos , Bifidobacterium/metabolismo , Ácidos y Sales Biliares/química , Ácidos y Sales Biliares/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Clostridium/metabolismo , Estudios de Cohortes , Enfermedad de Crohn/metabolismo , Enterococcus/metabolismo , Ésteres/química , Ésteres/metabolismo , Ácidos Grasos/química , Ácidos Grasos/metabolismo , Enfermedades Inflamatorias del Intestino/metabolismo , Metabolómica/métodos , Fenotipo , Receptor X de Pregnano/metabolismo , Reproducibilidad de los Resultados , Espectrometría de Masas en Tándem , Amidas/química , Amidas/metabolismo
2.
Nature ; 626(8000): 859-863, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38326609

RESUMEN

Bacteria in the gastrointestinal tract produce amino acid bile acid amidates that can affect host-mediated metabolic processes1-6; however, the bacterial gene(s) responsible for their production remain unknown. Herein, we report that bile salt hydrolase (BSH) possesses dual functions in bile acid metabolism. Specifically, we identified a previously unknown role for BSH as an amine N-acyltransferase that conjugates amines to bile acids, thus forming bacterial bile acid amidates (BBAAs). To characterize this amine N-acyltransferase BSH activity, we used pharmacological inhibition of BSH, heterologous expression of bsh and mutants in Escherichia coli and bsh knockout and complementation in Bacteroides fragilis to demonstrate that BSH generates BBAAs. We further show in a human infant cohort that BBAA production is positively correlated with the colonization of bsh-expressing bacteria. Lastly, we report that in cell culture models, BBAAs activate host ligand-activated transcription factors including the pregnane X receptor and the aryl hydrocarbon receptor. These findings enhance our understanding of how gut bacteria, through the promiscuous actions of BSH, have a significant role in regulating the bile acid metabolic network.


Asunto(s)
Aciltransferasas , Amidohidrolasas , Aminas , Ácidos y Sales Biliares , Biocatálisis , Microbioma Gastrointestinal , Humanos , Aciltransferasas/metabolismo , Amidohidrolasas/metabolismo , Aminas/química , Aminas/metabolismo , Bacteroides fragilis/enzimología , Bacteroides fragilis/genética , Bacteroides fragilis/metabolismo , Ácidos y Sales Biliares/química , Ácidos y Sales Biliares/metabolismo , Estudios de Cohortes , Escherichia coli/enzimología , Escherichia coli/genética , Escherichia coli/metabolismo , Microbioma Gastrointestinal/fisiología , Ligandos , Receptor X de Pregnano/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Factores de Transcripción/metabolismo , Lactante , Técnicas de Cultivo de Célula
3.
Proc Natl Acad Sci U S A ; 121(6): e2317408121, 2024 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-38285953

RESUMEN

Light plays a central role in plant growth and development, providing an energy source and governing various aspects of plant morphology. Previous study showed that many polyadenylated full-length RNA molecules within the nucleus contain unspliced introns (post-transcriptionally spliced introns, PTS introns), which may play a role in rapidly responding to changes in environmental signals. However, the mechanism underlying post-transcriptional regulation during initial light exposure of young, etiolated seedlings remains elusive. In this study, we used FLEP-seq2, a Nanopore-based sequencing technique, to analyze nuclear RNAs in Arabidopsis (Arabidopsis thaliana) seedlings under different light conditions and found numerous light-responsive PTS introns. We also used single-nucleus RNA sequencing (snRNA-seq) to profile transcripts in single nucleus and investigate the distribution of light-responsive PTS introns across distinct cell types. We established that light-induced PTS introns are predominant in mesophyll cells during seedling de-etiolation following exposure of etiolated seedlings to light. We further demonstrated the involvement of the splicing-related factor A. thaliana PROTEIN ARGININE METHYLTRANSFERASE 5 (AtPRMT5), working in concert with the E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), a critical repressor of light signaling pathways. We showed that these two proteins orchestrate light-induced PTS events in mesophyll cells and facilitate chloroplast development, photosynthesis, and morphogenesis in response to ever-changing light conditions. These findings provide crucial insights into the intricate mechanisms underlying plant acclimation to light at the cell-type level.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Proteína-Arginina N-Metiltransferasas , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Proteína-Arginina N-Metiltransferasas/genética , Proteína-Arginina N-Metiltransferasas/metabolismo , Plantones/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Luz
4.
Plant Cell ; 34(6): 2266-2285, 2022 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-35294019

RESUMEN

B-box containing proteins (BBXs) integrate light and various hormonal signals to regulate plant growth and development. Here, we demonstrate that the photomorphogenic repressors BBX28 and BBX29 positively regulate brassinosteroid (BR) signaling in Arabidopsis thaliana seedlings. Treatment with the BR brassinolide stabilized BBX28 and BBX29, which partially depended on BR INSENSITIVE1 (BRI1) and BIN2. bbx28 bbx29 seedlings exhibited larger cotyledon aperture than the wild-type when treated with brassinazole in the dark, which partially suppressed the closed cotyledons of brassinazole resistant 1-1D (bzr1-1D). Consistently, overexpressing BBX28 and BBX29 partially rescued the short hypocotyls of bri1-5 and bin2-1 in both the dark and light, while the loss-of-function of BBX28 and BBX29 partially suppressed the long hypocotyls of bzr1-1D in the light. BBX28 and BBX29 physically interacted with BR-ENHANCED EXPRESSION1 (BEE1), BEE2, and BEE3 and enhanced their binding to and activation of their target genes. Moreover, BBX28 and BBX29 as well as BEE1, BEE2, and BEE3 increased BZR1 accumulation to promote the BR signaling pathway. Therefore, both BBX28 and BBX29 interact with BEE1, BEE2, and BEE3 to orchestrate light and BR signaling by facilitating the transcriptional activity of BEE target genes. Our study provides insights into the pivotal roles of BBX28 and BBX29 as signal integrators in ensuring normal seedling development.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/fisiología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brasinoesteroides/metabolismo , Brasinoesteroides/farmacología , Regulación de la Expresión Génica de las Plantas/genética , Proteínas Quinasas/metabolismo , Plantones/genética , Plantones/metabolismo , Transducción de Señal , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
5.
Hepatology ; 77(1): 239-255, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-35460276

RESUMEN

BACKGROUND AND AIMS: Peroxisome proliferator-activated receptor α (PPARα) regulates fatty acid transport and catabolism in liver. However, the role of intestinal PPARα in lipid homeostasis is largely unknown. Here, intestinal PPARα was examined for its modulation of obesity and NASH. APPROACH AND RESULTS: Intestinal PPARα was activated and fatty acid-binding protein 1 (FABP1) up-regulated in humans with obesity and high-fat diet (HFD)-fed mice as revealed by using human intestine specimens or HFD/high-fat, high-cholesterol, and high-fructose diet (HFCFD)-fed C57BL/6N mice and PPARA -humanized, peroxisome proliferator response element-luciferase mice. Intestine-specific Ppara or Fabp1 disruption in mice fed a HFD or HFCFD decreased obesity-associated metabolic disorders and NASH. Molecular analyses by luciferase reporter assays and chromatin immunoprecipitation assays in combination with fatty acid uptake assays in primary intestinal organoids revealed that intestinal PPARα induced the expression of FABP1 that in turn mediated the effects of intestinal PPARα in modulating fatty acid uptake. The PPARα antagonist GW6471 improved obesity and NASH, dependent on intestinal PPARα or FABP1. Double-knockout ( Ppara/Fabp1ΔIE ) mice demonstrated that intestinal Ppara disruption failed to further decrease obesity and NASH in the absence of intestinal FABP1. Translationally, GW6471 reduced human PPARA-driven intestinal fatty acid uptake and improved obesity-related metabolic dysfunctions in PPARA -humanized, but not Ppara -null, mice. CONCLUSIONS: Intestinal PPARα signaling promotes NASH progression through regulating dietary fatty acid uptake through modulation of FABP1, which provides a compelling therapeutic target for NASH treatment.


Asunto(s)
Enfermedad del Hígado Graso no Alcohólico , Humanos , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/metabolismo , PPAR alfa/metabolismo , Ratones Endogámicos C57BL , Hígado/metabolismo , Dieta Alta en Grasa/efectos adversos , Obesidad/metabolismo , Ratones Noqueados , Intestinos , Proteínas de Unión a Ácidos Grasos/metabolismo , Proteínas de Unión a Ácidos Grasos/farmacología , Ácidos Grasos/metabolismo
6.
J Exp Bot ; 75(11): 3452-3466, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38497815

RESUMEN

The 2-(2-phenethyl)chromones (PECs) are the signature constituents responsible for the fragrance and pharmacological properties of agarwood. O-Methyltransferases (OMTs) are necessary for the biosynthesis of methylated PECs, but there is little known about OMTs in Aquilaria sinensis. In this study, we identified 29 OMT genes from the A. sinensis genome. Expression analysis showed they were differentially expressed in different tissues and responded to drill wounding. Comprehensive analysis of the gene expression and methylated PEC content revealed that AsOMT2, AsOMT8, AsOMT11, AsOMT16, and AsOMT28 could potentially be involved in methylated PECs biosynthesis. In vitro enzyme assays and functional analysis in Nicotiana benthamiana demonstrated that AsOMT11 and AsOMT16 could methylate 6-hydroxy-2-(2-phenylethyl)chromone to form 6-methoxy-2-(2-phenylethyl)chromone. A transient overexpression experiment in the variety 'Qi-Nan' revealed that AsOMT11 and AsOMT16 could significantly promote the accumulation of three major methylated PECs. Our results provide candidate genes for the mass production of methylated PECs using synthetic biology.


Asunto(s)
Metiltransferasas , Proteínas de Plantas , Thymelaeaceae , Thymelaeaceae/genética , Thymelaeaceae/metabolismo , Thymelaeaceae/enzimología , Metiltransferasas/metabolismo , Metiltransferasas/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Cromonas/metabolismo , Madera/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Metilación , Regulación de la Expresión Génica de las Plantas , Flavonoides
7.
Rapid Commun Mass Spectrom ; 38(17): e9844, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38932679

RESUMEN

RATIONALE: Sphingomyelins (SMs) and resulting metabolic products serve important functional and cell signaling roles and can act as potential biomarkers and therapeutic targets in many pathological disorders. SMs each contain a sphingoid base, an amide-linked fatty acyl chain, and a phosphocholine headgroup. Despite these simple building blocks, variations and modifications of both the sphingoid base and the fatty acyl chain result in a diverse array of structurally complicated SM compounds. Conventional tandem mass spectrometry (MS/MS) using the collision-induced dissociation (CID) method only provides limited structural information, necessitating other tools to unravel the structural complexity of these lipids. METHODS: We utilize electron-induced dissociation (EID) and sequential CID/EID approaches to elucidate detailed structural features of SMs. Integrating the CID/EID method into an imaging MS workflow enables accurate identification of SMs directly from kidney tissue. RESULTS: The application of EID enables identification of SMs at the molecular species level, identifying the sphingosine base and the amide-linked fatty acyl chains. Furthermore, removal of the phosphocholine headgroup via CID followed by sequential EID in an MS3 analysis (CID/EID) enhances the structural information obtained. CID/EID provides diagnostic fragmentation patterns revealing the hydroxylation site and double bond position in both the sphingosine base and amide-linked fatty acyl chains. CONCLUSIONS: Detailed structural information of SMs from synthetic standards and biological tissue samples is obtained using an alternative electron-based dissociation method. Accurate characterization of SMs promises to better inform studies of tissue biochemistry, lipid metabolism, and molecular pathology.


Asunto(s)
Esfingomielinas , Espectrometría de Masas en Tándem , Esfingomielinas/química , Espectrometría de Masas en Tándem/métodos , Animales , Riñón/química , Electrones
8.
Cereb Cortex ; 33(7): 3910-3921, 2023 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-35972410

RESUMEN

Speech perception depends on the dynamic interplay of bottom-up and top-down information along a hierarchically organized cortical network. Here, we test, for the first time in the human brain, whether neural processing of attended speech is dynamically modulated by task demand using a context-free discrimination paradigm. Electroencephalographic signals were recorded during 3 parallel experiments that differed only in the phonological feature of discrimination (word, vowel, and lexical tone, respectively). The event-related potentials (ERPs) revealed the task modulation of speech processing at approximately 200 ms (P2) after stimulus onset, probably influencing what phonological information to retain in memory. For the phonological comparison of sequential words, task modulation occurred later at approximately 300 ms (N3 and P3), reflecting the engagement of task-specific cognitive processes. The ERP results were consistent with the changes in delta-theta neural oscillations, suggesting the involvement of cortical tracking of speech envelopes. The study thus provides neurophysiological evidence for goal-oriented modulation of attended speech and calls for speech perception models incorporating limited memory capacity and goal-oriented optimization mechanisms.


Asunto(s)
Percepción del Habla , Humanos , Percepción del Habla/fisiología , Estimulación Acústica/métodos , Objetivos , Potenciales Evocados/fisiología , Habla/fisiología , Electroencefalografía/métodos
9.
Mar Drugs ; 22(2)2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38393028

RESUMEN

Oxidative stress, which damages cellular components and causes mitochondrial dysfunction, occurs in a variety of human diseases, including neurological disorders. The clearance of damaged mitochondria via mitophagy maintains the normal function of mitochondria and facilitates cell survival. Astaxanthin is an antioxidant known to have neuroprotective effects, but the underlying mechanisms remain unclear. This study demonstrated that astaxanthin inhibited H2O2-induced apoptosis in SH-SY5Y cells by ameliorating mitochondrial damage and enhancing cell survival. H2O2 treatment significantly reduced the levels of activated Akt and mTOR and induced mitophagy, while pretreatment with astaxanthin prevented H2O2-induced inhibition of Akt and mTOR and attenuated H2O2-induced mitophagy. Moreover, the inhibition of Akt attenuated the protective effect of astaxanthin against H2O2-induced cytotoxicity. Taken together, astaxanthin might inhibit H2O2-induced apoptosis by protecting mitochondrial function and reducing mitophagy. The results also indicate that the Akt/mTOR signaling pathway was critical for the protection of astaxanthin against H2O2-induced cytotoxicity. The results from the present study suggest that astaxanthin can reduce neuronal oxidative injury and may have the potential to be used for preventing neurotoxicity associated with neurodegenerative diseases.


Asunto(s)
Neuroblastoma , Proteínas Proto-Oncogénicas c-akt , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Peróxido de Hidrógeno/toxicidad , Mitofagia , Neuroblastoma/tratamiento farmacológico , Apoptosis , Estrés Oxidativo , Serina-Treonina Quinasas TOR/metabolismo , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Xantófilas
10.
Sensors (Basel) ; 24(11)2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38894201

RESUMEN

Information-Centric Networking (ICN) is the emerging next-generation internet paradigm. The Low Earth Orbit (LEO) satellite mega-constellation based on ICN can achieve seamless global coverage and provide excellent support for Internet of Things (IoT) services. Additionally, in-network caching, typically characteristic of ICN, plays a paramount role in network performance. Therefore, the in-network caching policy is one of the hotspot problems. Especially, compared to caching traditional internet content, in-networking caching IoT content is more challenging, since the IoT content lifetime is small and transient. In this paper, firstly, the framework of the LEO satellite mega-constellation Information-Centric Networking for IoT (LEO-SMC-ICN-IoT) is proposed. Then, introducing the concept of "viscosity", the proposed Caching Algorithm based on the Random Forest (CARF) policy of satellite nodes combines both content popularity prediction and satellite nodes location prediction, for achieving good cache matching between the satellite nodes and content. And using the matching rule, the Random Forest (RF) algorithm is adopted to predict the matching relationship among satellite nodes and content for guiding the deployment of caches. Especially, the content is cached in advance at the future satellite to maintain communication with the current ground segment at the time of satellite switchover. Additionally, the policy considers both the IoT content lifetime and the freshness. Finally, a simulation platform with LEO satellite mega-constellation based on ICN is developed in Network Simulator 3 (NS-3). The simulation results show that the proposed caching policy compared with the Leave Copy Everywhere (LCE), the opportunistic (OPP), the Leave Copy down (LCD), and the probabilistic algorithm which caches each content with probability 0.5 (prob 0.5) yield a significant performance improvement, such as the average number of hops, i.e., delay, cache hit rate, and throughput.

11.
Nano Lett ; 23(17): 8295-8302, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37638790

RESUMEN

Photodetectors displaying an ultraviolet (UV) spectral response window are typically based on wide-bandgap semiconductors that have long been dominated by inorganic materials that suffer from bottlenecks of low flexibility and a limited material family. Here, we synthesized a novel organic small molecule and controlled its crystallization to suppress leakage currents and facilitate separation of the carriers, and the relationship between the nanoscale phase separation morphology and the optoelectrical performance of the photodetectors is disclosed. Our optimized organic photodetector (OPD) presents a UV spectral response window, with superior self-powered responsivities of 45 mA/W (under 250 nm light) and 70 mA/W (under 300 nm light), outperforming the Si photodiode and rivaling other reported UV self-powered photodetectors. Finally, an imaging system was constructed to demonstrate the application potential of the OPD in UV flexible imaging with high-resolution arrays of 400 pixels × 400 pixels (5 µm × 5 µm per pixel), which could work in bent states and successfully output images of micrometer-sized objects.

12.
Heart Lung Circ ; 33(5): 605-638, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38242833

RESUMEN

AIM: With the advancement of anti-cancer medicine, cardiovascular toxicities due to cancer therapies are common in oncology patients, resulting in increased mortality and economic burden. Cardiovascular toxicities caused by cancer therapies include different severities of cardiomyopathy, arrhythmia, myocardial ischaemia, hypertension, and thrombosis, which may lead to left ventricular dysfunction and heart failure. This scoping review aimed to summarise the mechanisms of cardiovascular toxicities following various anti-cancer treatments and potential predictive biomarkers for early detection. METHODS: PubMed, Cochrane, Embase, Web of Science, Scopus, and CINAHL databases were searched for original studies written in English related to the mechanisms of cardiovascular toxicity induced by anti-cancer therapies, including chemotherapy, targeted therapy, immunotherapy, radiation therapy, and relevant biomarkers. The search and title/abstract screening were conducted independently by two reviewers, and the final analysed full texts achieved the consensus of the two reviewers. RESULTS: A total of 240 studies were identified based on their titles and abstracts. In total, 107 full-text articles were included in the analysis. Cardiomyocyte and endothelial cell apoptosis caused by oxidative stress injury, activation of cell apoptosis, blocking of normal cardiovascular protection signalling pathways, overactivation of immune cells, and myocardial remodelling were the main mechanisms. Promising biomarkers for anti-cancer therapies related to cardiovascular toxicity included placental growth factor, microRNAs, galectin-3, and myeloperoxidase for the early detection of cardiovascular toxicity. CONCLUSION: Understanding the mechanisms of cardiovascular toxicity following various anti-cancer treatments could provide implications for future personalised treatment methods to protect cardiovascular function. Furthermore, specific early sensitive and stable biomarkers of cardiovascular system damage need to be identified to predict reversible damage to the cardiovascular system and improve the effects of anti-cancer agents.


Asunto(s)
Antineoplásicos , Biomarcadores , Enfermedades Cardiovasculares , Neoplasias , Humanos , Neoplasias/tratamiento farmacológico , Biomarcadores/metabolismo , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/diagnóstico , Antineoplásicos/efectos adversos , Cardiotoxicidad/etiología , Cardiotoxicidad/diagnóstico
13.
Br J Cancer ; 128(2): 363-374, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36396820

RESUMEN

BACKGROUND: Chemotherapy resistance is the major cause of recurrence in patients with colorectal cancer (CRC). A previous study found that Fusobacterium (F.) nucleatum promoted CRC chemoresistance. Additionally, metformin rescued F. nucleatum-induced tumorigenicity of CRC. Here, we aimed to investigate whether metformin could revert F. nucleatum-induced chemoresistance and explore the mechanism. METHODS: The role of metformin in F. nucleatum-infected CRC cells was confirmed using cell counting kit 8 assays and CRC xenograft mice. Stemness was identified by tumorsphere formation. Bioinformatic analyses were used to explore the regulatory molecules involved in metformin and F. nucleatum-mediated regulation of the sonic hedgehog pathway. RESULTS: We found that metformin abrogated F. nucleatum-promoted CRC resistance to chemotherapy. Furthermore, metformin attenuated F. nucleatum-stimulated stemness by inhibiting sonic hedgehog signaling. Mechanistically, metformin diminished sonic hedgehog signaling proteins by targeting the MYC/miR-361-5p cascade to reverse F. nucleatum-induced stemness, thereby rescuing F. nucleatum-triggered chemoresistance in CRC. CONCLUSIONS: Metformin acts on F. nucleatum-infected CRC via the MYC/miR-361-5p/sonic hedgehog pathway cascade, subsequently reversing stemness and abolishing F. nucleatum-triggered chemoresistance. Our results identified metformin intervention as a potential clinical treatment for patients with chemoresistant CRC with high amounts of F. nucleatum.


Asunto(s)
Neoplasias Colorrectales , MicroARNs , Humanos , Animales , Ratones , MicroARNs/genética , MicroARNs/metabolismo , Proteínas Hedgehog/genética , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Fusobacterium nucleatum , Resistencia a Antineoplásicos/genética
14.
Anal Chem ; 95(42): 15707-15715, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37818979

RESUMEN

The chemical complexity of biological tissues creates challenges in the analysis of lipids via imaging mass spectrometry. The presence of isobaric and isomeric compounds introduces chemical noise that makes it difficult to unambiguously identify and accurately map the spatial distributions of these compounds. Electron-induced dissociation (EID) has previously been shown to profile phosphatidylcholine (PCs) sn-isomers directly from rat brain tissue in matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry. However, the acquisition of true pixel-by-pixel images, as opposed to regional profiling measurements, using EID is difficult due to low fragmentation efficiency and precursor ion signal dilution into multiple fragment ion channels, resulting in low sensitivity. In this work, we have developed a sequential collision-induced dissociation (CID)/EID method to visualize the distribution of sn-isomers in MALDI imaging mass spectrometry experiments. Briefly, CID is performed on sodium-adducted PCs, which results in facile loss of the phosphocholine headgroup. This ion is then subjected to an EID analysis. Since the lipid headgroup is removed prior to EID, a major fragmentation pathway common to EID ion activation is eliminated, resulting in a more sensitive analysis. This sequential CID/EID workflow generates sn-specific fragment ions allowing for the assignment of the sn-positions. Carbon-carbon double-bond (C═C) positions are also localized along the fatty acyl tails by the presence of a 2 Da shift pattern in the fragment ions arising from carbon-carbon bond cleavages. Moreover, the integration of the CID/EID method into MALDI imaging mass spectrometry enables the mapping of the absolute and relative distribution of sn-isomers at every pixel. The localized relative abundances of sn-isomers vary throughout brain substructures and likely reflect different biological functions and metabolism.


Asunto(s)
Electrones , Fosfatidilcolinas , Ratas , Animales , Iones/química , Encéfalo , Carbono
15.
Breast Cancer Res Treat ; 197(2): 343-354, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36409395

RESUMEN

PURPOSE: Whether peripheral immune cell subsets can predict pathological complete response (pCR) in breast cancer patients remains to be elucidated. We aimed to dissect the relationship between peripheral immune cell subsets and pCR. METHODS: Two hundred and twenty-six eligible patients from two prospective clinical trials (SHPD001 and SHPD002) in China were randomly divided into a training cohort and a validation cohort. The breast cancer subtypes in this study included hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative (n = 95), HER2-positive (n = 100), and triple negative (n = 31) breast cancer. We defined the "Neo-Peripheral Adaptive Immune Score" for neoadjuvant chemotherapy (neoPAI Score) based on the percentages of CD4 + T cells, CD8 + T cells, B cells, and the CD4 + /CD8 + ratio in peripheral blood. We also evaluated the ability of the neoPAI Score derived from tumor-infiltrating immune cells (TIICs) to predict survival by employing The Cancer Genome Atlas-Breast Cancer (TCGA-BRCA) database. RESULTS: In the training cohort, multivariate analysis showed that HR status [odds ratio (OR) 0.325; 95% confidence interval (CI) 0.135-0.761; P = 0.010], HER2 status (OR 2.657; 95% CI 1.266-5.730; P = 0.011), Ki67 index (OR 3.191; 95% CI 1.509-6.956; P = 0.003), histological grade (OR 2.297; 95% CI 1.031-5.290; P = 0.045) and neoPAI Score (OR 4.451; 95% CI 1.608-13.068; P = 0.005) were independent predictors of pCR. In the validation cohort, histological grade (OR 3.779; 95% CI 3.793-1.136 × 103; P = 0.008) and neoPAI Score (OR 90.828; 95% CI 3.827-9.843 × 103; P = 0.019) were independent predictors of pCR. The Immune Model that integrated the neoPAI Score was more accurate in predicting pCR than the Clinical Model that exclusively contained clinicopathological parameters in both cohorts. In TCGA-BRCA database, the neoPAI Score constructed from TIICs can predict the progression-free interval (P = 0.048) of breast cancer. CONCLUSION: The neoPAI Score defined by the percentages of peripheral immune cell subsets could be used as a potential biomarker for neoadjuvant chemotherapy efficacy.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Estudios Prospectivos , Terapia Neoadyuvante , Supervivencia sin Enfermedad , Receptor ErbB-2/metabolismo , Inducción de Remisión , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico
16.
Small ; 19(10): e2206070, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36538751

RESUMEN

Tandem catalysis is a promising way to break the limitation of linear scaling relationship for enhancing efficiency, and the desired tandem catalysts for electrochemical CO2 reduction reaction (CO2 RR) are urgent to be developed. Here, a tandem electrocatalyst created by combining Cu foil (CF) with a single-site Cu(II) metal-organic framework (MOF), named as Cu-MOF-CF, to realize improved electrochemical CO2 RR performance, is reported. The Cu-MOF-CF shows suppression of CH4 , great increase in C2 H4 selectivity (48.6%), and partial current density of C2 H4 at -1.11 V versus reversible hydrogen electrode. The outstanding performance of Cu-MOF-CF for CO2 RR results from the improved microenvironment of the Cu active sites that inhibits CH4 production, more CO intermediate produced by single-site Cu-MOF in situ for CF, and the enlarged active surface area by porous Cu-MOF. This work provides a strategy to combine MOFs with copper-based electrocatalysts to establish high-efficiency electrocatalytic CO2 RR.

17.
Small ; 19(9): e2206310, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36587965

RESUMEN

2D Ruddlesden-Popper perovskites (PVKs) have recently shown overwhelming potential in various optoelectronic devices on account of enhanced stability to their 3D counterparts. So far, regulating the phase distribution and orientation of 2D perovskite thin films remains challenging to achieve efficient charge transport. This work elucidates the balance struck between sufficient gradient sedimentation of perovskite colloids and less formation of small-n phases, which results in the layered alignment of phase compositions and thus in enhanced photoresponse. The solvent engineering strategy, together with the introduction of poly(3,4-ethylene-dioxythiophene):polystyrene sulfonate (PEDOT:PSS) and PC71 BM layer jointly contribute to outstanding self-powered performance of indium tin oxide/PEDOT:PSS/PVK/PC71 BM/Ag device, with a photocurrent of 18.4 µA and an on/off ratio up to 2800. The as-fabricated photodetector exhibits high sensitivity characteristics with the peak responsivity of 0.22 A W-1 and the detectivity up to 1.3 × 1012  Jones detected at UV-A region, outperforming most reported perovskite-based UV photodetectors and maintaining high stability over a wide spectrum ranging from UV to visible region. This discovery supplies deep insights into the control of ordered phases and crystallinity in quasi-2D perovskite films for high-performance optoelectronic devices.

18.
Clin Exp Rheumatol ; 41(11): 2257-2263, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37279146

RESUMEN

OBJECTIVES: To define the clinical and prognostic features associated with anti-Ro52 autoantibodies in patients with connective tissue diseases with interstitial lung disease (CTD-ILD). METHODS: A total of 238 patients with CTD-ILD were included in this single-centre retrospective cohort study. Patients with positive anti-Ro52 antibodies were selected as the study group, and those with negative anti-Ro52 antibodies were included in the control group. Clinical and follow-up data were analysed. RESULTS: Among 238 patients, 145 (60.92%) were positive for the anti-Ro52 antibody. These patients were more likely to have respiratory symptoms at baseline, with more organising pneumonia (OP) patterns and worse forced vital capacity (FVC). Follow-up data were obtained for ILD progression in 170 patients. Varying degrees of progression in pulmonary function (PF) or imaging were found in 48 patients (28.24%) with CTD-ILD. A dichotomous logistic analysis based on the presence or absence of progress showed no correlation with anti-Ro52 antibodies. During the follow-up of 170 patients, there were 35 deaths: 24 in the anti-Ro52 antibody positive group and 11 in the anti-Ro52 antibody negative group. Kaplan-Meier survival curves were used to describe the difference in survival between the two groups (mortality 17.14% vs. 12.5%, log-rank p=0.287). The multivariate logistic analysis showed that ILD progression was associated with older age, worse FVC and diffusion capacity for carbon monoxide at baseline, higher levels of C-reactive protein, serum ferritin, immunoglobulin G and lower absolute lymphocyte count. CONCLUSIONS: Anti-Ro52 antibodies may predict more severe lung damage in CTD-ILD; however, anti-Ro52 antibodies were not correlated with progression and death in patients with ILD.


Asunto(s)
Enfermedades del Tejido Conjuntivo , Enfermedades Pulmonares Intersticiales , Humanos , Pronóstico , Estudios Retrospectivos , Autoanticuerpos , Enfermedades Pulmonares Intersticiales/diagnóstico , Enfermedades Pulmonares Intersticiales/etiología , Enfermedades del Tejido Conjuntivo/complicaciones , Enfermedades del Tejido Conjuntivo/diagnóstico
19.
Clin Exp Rheumatol ; 41(2): 247-253, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-35819809

RESUMEN

OBJECTIVES: Anti-nuclear matrix protein 2 (NXP2) antibody is a rare myositis-specific antibody. Thus, the pattern and prognosis of interstitial lung disease (ILD) in NXP2-positive patients remain unclear. This study investigates the clinical features and effects of pulmonary complications on survival in NXP2-positive patients. METHODS: We retrospectively analysed the clinical and follow-up data of a cohort of 33 hospitalised adult patients with anti-NXP2 antibody positivity at three tertiary rheumatology centres from June 2017 to December 2020. RESULTS: Thirty-three patients were enrolled, and 87.9% (29/33) had dermatomyositis. The major pulmonary lesions manifested as various types of ILD (14/33, 42.4%), bilateral pleural effusion (2/33, 6.1%) and diffuse alveolar haemorrhage (1/33, 3%). Only 3 patients (3/33, 9.1%) had respiratory symptoms at onset. The most common lung imaging manifestations were non-specific interstitial pneumonia (NSIP) and/or organising pneumonia (OP) (11/14, 78.6%). Patients in the ILD group were older than those in the non-ILD group (p=0.002). Logistic regression analysis showed that age (p=0.008) was the only independent predictor for ILD. Kaplan-Meier survival curves displayed no association between ILD and all-cause death (log-rank p=0.84). None of the deaths during follow-up were directly related to ILD. CONCLUSIONS: Adult patients with anti-NXP2 antibody positivity mainly had dermatomyositis. Concurrent ILD is not uncommon, but clinical manifestations are often latent. NSIP and/or OP are the most common patterns. ILD is more common in older age groups. Although the prognosis of patients in the ILD group is not very poor, early screening may help to improve prognosis and quality of life.


Asunto(s)
Dermatomiositis , Enfermedades Pulmonares Intersticiales , Humanos , Adulto , Anciano , Estudios de Seguimiento , Dermatomiositis/complicaciones , Estudios Retrospectivos , Calidad de Vida , Enfermedades Pulmonares Intersticiales/etiología , Pronóstico , Autoanticuerpos
20.
Environ Sci Technol ; 57(50): 21470-21482, 2023 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-38050842

RESUMEN

NOx and CH3SH as two typical air pollutants widely coexist in various energy and industrial processes; hence, it is urgent to develop highly efficient catalysts to synergistically eliminate NOx and CH3SH. However, the catalytic system for synergistically eliminating NOx and CH3SH is seldom investigated to date. Meanwhile, the deactivation effects of CH3SH on catalysts and the formation mechanism of toxic byproducts emitted from the synergistic catalytic elimination reaction are still vague. Herein, selective synergistic catalytic elimination (SSCE) of NOx and CH3SH via engineering deep oxidation sites over Cu-modified Nb-Fe composite oxides supported on TiO2 catalyst against toxic CO and HCN byproducts formation has been originally demonstrated. Various spectroscopic and microscopic characterizations demonstrate that the sufficient chemisorbed oxygen species induced by the persistent electron transfer from Nb-Fe composite oxides to copper oxides can deeply oxidize HCOOH to CO2 for avoiding highly toxic byproducts formation. This work is of significance in designing superior catalysts employed in more complex working conditions and sheds light on the progress in the SSCE of NOx and sulfur-containing volatile organic compounds.


Asunto(s)
Contaminantes Atmosféricos , Óxidos , Oxidación-Reducción , Óxidos/análisis , Óxidos/química , Oxígeno , Transporte de Electrón , Catálisis , Amoníaco/química
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