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1.
Nature ; 575(7783): 505-511, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31723265

RESUMEN

Chronic liver disease due to alcohol-use disorder contributes markedly to the global burden of disease and mortality1-3. Alcoholic hepatitis is a severe and life-threatening form of alcohol-associated liver disease. The gut microbiota promotes ethanol-induced liver disease in mice4, but little is known about the microbial factors that are responsible for this process. Here we identify cytolysin-a two-subunit exotoxin that is secreted by Enterococcus faecalis5,6-as a cause of hepatocyte death and liver injury. Compared with non-alcoholic individuals or patients with alcohol-use disorder, patients with alcoholic hepatitis have increased faecal numbers of E. faecalis. The presence of cytolysin-positive (cytolytic) E. faecalis correlated with the severity of liver disease and with mortality in patients with alcoholic hepatitis. Using humanized mice that were colonized with bacteria from the faeces of patients with alcoholic hepatitis, we investigated the therapeutic effects of bacteriophages that target cytolytic E. faecalis. We found that these bacteriophages decrease cytolysin in the liver and abolish ethanol-induced liver disease in humanized mice. Our findings link cytolytic E. faecalis with more severe clinical outcomes and increased mortality in patients with alcoholic hepatitis. We show that bacteriophages can specifically target cytolytic E. faecalis, which provides a method for precisely editing the intestinal microbiota. A clinical trial with a larger cohort is required to validate the relevance of our findings in humans, and to test whether this therapeutic approach is effective for patients with alcoholic hepatitis.


Asunto(s)
Bacteriófagos/fisiología , Enterococcus faecalis/patogenicidad , Enterococcus faecalis/virología , Microbioma Gastrointestinal , Hepatitis Alcohólica/microbiología , Hepatitis Alcohólica/terapia , Terapia de Fagos , Alcoholismo/complicaciones , Alcoholismo/microbiología , Animales , Enterococcus faecalis/aislamiento & purificación , Etanol/efectos adversos , Hígado Graso/complicaciones , Hígado Graso/microbiología , Heces/microbiología , Femenino , Vida Libre de Gérmenes , Hepatitis Alcohólica/complicaciones , Hepatitis Alcohólica/mortalidad , Hepatocitos/efectos de los fármacos , Hepatocitos/patología , Humanos , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Perforina/metabolismo
2.
Small ; 20(37): e2400783, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38573959

RESUMEN

Endowing conventional materials with specific functions that are hardly available is invariably of significant importance but greatly challenging. TiO2 is proven to be highly active for the photocatalytic hydrogen evolution while intrinsically inert for electrocatalytic hydrogen evolution reaction (HER) due to its poor electrical conductivity and unfavorable hydrogen adsorption/desorption behavior. Herein, the first activation of inert TiO2 for electrocatalytic HER is demonstrated by synergistically modulating the positions of d-band center and triggering hydrogen spillover through the dual doping-induced partial phase transition. The N, F co-doping-induced partial phase transition from anatase to rutile phase in TiO2 (AR-TiO2|(N,F)) exhibits extraordinary HER performance with overpotentials of 74, 80, and 142 mV at a current density of 10 mA cm-2 in 1.0 M KOH, 0.5 M H2SO4, and 1.0 M phosphate-buffered saline electrolytes, respectively, which are substantially better than pure TiO2, and even superior to the benchmark Pt/C catalysts. These findings may open a new avenue for the development of low-cost alternative to noble metal catalysts for electrocatalytic hydrogen production.

3.
Opt Express ; 32(8): 13408-13418, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38859312

RESUMEN

Fiber optic hydrophones (FOHs) offer the notable advantage of electromagnetic interference resistance. Nevertheless, overcoming the challenge of sustaining stable, high-performance operation in intricate underwater settings at a low cost remains a considerable obstacle for them. To circumvent the restrictions noted above, we employed a miniaturized FOH, utilizing an easily fabricated extrinsic Fabry-Perot interferometer (EFPI) which is made up of a composite chromium-aluminum (Cr-Al) membrane and fiber. The linear demodulation also suppresses the drift issue in the output spectrum. The average sound pressure sensitivity of the sensor, according to experimental findings, is around -139.15 dB re 1 V/µPa, while the equivalent noise sound pressure at 1 kHz is 51.52 dB re 1 µPa/Hz1/2. This sensor has a lot of potential because of features like sensitive low-frequency response and noise performance.

4.
Rapid Commun Mass Spectrom ; 38(19): e9880, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39159996

RESUMEN

RATIONALE: Isopsoralen (ISO), a quality control marker (Q-marker) in Psoraleae Fructus, is proven to present an obvious anti-osteoporosis effect. Until now, the metabolism and anti-osteoporosis mechanisms of ISO have not been fully elucidated, greatly restricting its drug development. METHODS: The metabolites of ISO in rats were profiled by using ultrahigh-performance liquid chromatography coupled with time-of-flight mass spectrometry. The potential anti-osteoporosis mechanism of ISO in vivo was predicted by using network pharmacology. RESULTS: A total of 15 metabolites were characterized in rats after ingestion of ISO (20 mg/kg/day, by gavage), including 2 in plasma, 12 in urine, 6 in feces, 1 in heart, 3 in liver, 1 in spleen, 1 in lung, 3 in kidney, and 2 in brain. The pharmacology network results showed that ISO and its metabolites could regulate AKT1, SRC, NFKB1, EGFR, MAPK3, etc., involved in the prolactin signaling pathway, ErbB signaling pathway, thyroid hormone pathway, and PI3K-Akt signaling pathway. CONCLUSIONS: This is the first time for revealing the in vivo metabolism features and potential anti-osteoporosis mechanism of ISO by metabolite profiling and network pharmacology, providing data for further verification of pharmacological mechanism.


Asunto(s)
Furocumarinas , Farmacología en Red , Psoralea , Ratas Sprague-Dawley , Animales , Furocumarinas/farmacología , Furocumarinas/química , Psoralea/química , Ratas , Cromatografía Líquida de Alta Presión/métodos , Masculino , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Control de Calidad , Biomarcadores/análisis , Biomarcadores/metabolismo , Biomarcadores/orina , Frutas/química , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/administración & dosificación , Espectrometría de Masas/métodos , Conservadores de la Densidad Ósea/farmacología , Metaboloma/efectos de los fármacos , Metabolómica/métodos
5.
Rapid Commun Mass Spectrom ; 38(19): e9872, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39044122

RESUMEN

RATIONALE: Eucommia cortex is the core herb in traditional Chinese medicine preparations for the treatment of osteoporosis. Pinoresinol diglucoside (PDG), the quality control marker and the key pharmacodynamic component in Eucommia cortex, has attracted global attention because of its definite effects on osteoporosis. However, the in vivo metabolic characteristics of PDG and its anti-osteoporotic mechanism are still unclear, restricting its development and application. METHODS: Ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry was used to analyze the metabolic characteristics of PDG in rats, and its anti-osteoporosis targets and mechanism were predicted using network pharmacology. RESULTS: A total of 51 metabolites were identified or tentatively characterized in rats after oral administration of PDG (10 mg/kg/day), including 9 in plasma, 28 in urine, 13 in feces, 10 in liver, 4 in heart, 3 in spleen, 11 in kidneys, and 5 in lungs. Furan-ring opening, dimethoxylation, glucuronidation, and sulfation were the main metabolic characteristics of PDG in vivo. The potential mechanism of PDG against osteoporosis was predicted using network pharmacology. PDG and its metabolites could regulate BCL2, MARK3, ALB, and IL6, involving PI3K-Akt signaling pathway, estrogen signaling pathway, and so on. CONCLUSIONS: This study was the first to demonstrate the metabolic characteristics of PDG in vivo and its potential anti-osteoporosis mechanism, providing the data for further pharmacological validation of PDG in the treatment of osteoporosis.


Asunto(s)
Lignanos , Farmacología en Red , Osteoporosis , Ratas Sprague-Dawley , Animales , Lignanos/farmacología , Lignanos/metabolismo , Osteoporosis/tratamiento farmacológico , Osteoporosis/metabolismo , Ratas , Cromatografía Líquida de Alta Presión/métodos , Masculino , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/administración & dosificación , Medicamentos Herbarios Chinos/metabolismo , Medicamentos Herbarios Chinos/química , Metabolómica/métodos , Glucósidos/farmacología , Metaboloma/efectos de los fármacos , Espectrometría de Masas/métodos
6.
Cereb Cortex ; 33(14): 8942-8955, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37183188

RESUMEN

Advancements in deep learning algorithms over the past decade have led to extensive developments in brain-computer interfaces (BCI). A promising imaging modality for BCI is magnetoencephalography (MEG), which is a non-invasive functional imaging technique. The present study developed a MEG sensor-based BCI neural network to decode Rock-Paper-scissors gestures (MEG-RPSnet). Unique preprocessing pipelines in tandem with convolutional neural network deep-learning models accurately classified gestures. On a single-trial basis, we found an average of 85.56% classification accuracy in 12 subjects. Our MEG-RPSnet model outperformed two state-of-the-art neural network architectures for electroencephalogram-based BCI as well as a traditional machine learning method, and demonstrated equivalent and/or better performance than machine learning methods that have employed invasive, electrocorticography-based BCI using the same task. In addition, MEG-RPSnet classification performance using an intra-subject approach outperformed a model that used a cross-subject approach. Remarkably, we also found that when using only central-parietal-occipital regional sensors or occipitotemporal regional sensors, the deep learning model achieved classification performances that were similar to the whole-brain sensor model. The MEG-RSPnet model also distinguished neuronal features of individual hand gestures with very good accuracy. Altogether, these results show that noninvasive MEG-based BCI applications hold promise for future BCI developments in hand-gesture decoding.


Asunto(s)
Interfaces Cerebro-Computador , Aprendizaje Profundo , Humanos , Magnetoencefalografía , Gestos , Electroencefalografía/métodos , Algoritmos
7.
Alzheimers Dement ; 20(1): 356-365, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37622539

RESUMEN

INTRODUCTION: Despite their increased application, the heritability of Alzheimer's disease (AD)-related blood-based biomarkers remains unexplored. METHODS: Plasma amyloid beta 40 (Aß40), Aß42, the Aß42/40 ratio, total tau (t-tau), and neurofilament light (NfL) data came from 1035 men 60 to 73 years of age (µ = 67.0, SD = 2.6). Twin models were used to calculate heritability and the genetic and environmental correlations between them. RESULTS: Additive genetics explained 44% to 52% of Aß42, Aß40, t-tau, and NfL. The Aß42/40 ratio was not heritable. Aß40 and Aß42 were genetically near identical (rg  = 0.94). Both Aß40 and Aß42 were genetically correlated with NfL (rg  = 0.35 to 0.38), but genetically unrelated to t-tau. DISCUSSION: Except for Aß42/40, plasma biomarkers are heritable. Aß40 and Aß42 share mostly the same genetic influences, whereas genetic influences on plasma t-tau and NfL are largely unique in early old-age men. The absence of genetic associations between the Aßs and t-tau is not consistent with the amyloid cascade hypothesis.


Asunto(s)
Enfermedad de Alzheimer , Masculino , Humanos , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides , Proteínas tau/genética , Biomarcadores , Fragmentos de Péptidos
8.
Angew Chem Int Ed Engl ; : e202404196, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39161281

RESUMEN

In this study, we present a novel plasma-enabled strategy for the rapid breakdown of various types of plastic wastes, including mixtures, into high-value carbon nanomaterials and hydrogen. The H2 yield and selectivity achieved through the catalyst-free plasma-enabled strategy are 14.2 and 5.9 times higher, respectively, compared to those obtained with conventional thermal pyrolysis. It is noteworthy that this catalyst-free plasma alone approach yields a significantly higher energy yield of H2 (gH2/kWh) compared to other pyrolysis processes. By coupling plasma pyrolysis with thermal catalytic process, employing of 1 wt.% M/CeO2 atomically dispersed catalysts can further enhance hydrogen production. Specifically, the 1 wt.% Co/CeO2 catalyst demonstrated excellent catalytic performance throughout the 10 cycles of plastic waste decomposition, achieving the highest H2 yield of 46.7 mmol/gplastic (equivalent to 64.4% of theoretical H2 production) and nearly 100% hydrogen atom recovery efficiency at the 7th cycle. Notably, the H2 yield achieved over the atomically dispersed Fe on CeO2 surface in the integrated plasma-thermal catalytic process is comparable to that obtained with Fe particles on CeO2 surface (10 wt.%). This innovative and straightforward approach provides a promising and expedient strategy for continuously converting diverse plastic waste streams into high-value products conducive to a circular plastic economy.

9.
J Am Chem Soc ; 2023 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-37792912

RESUMEN

Dry reforming of methane (DRM) has been investigated for more than a century; the paramount stumbling block in its industrial application is the inevitable sintering of catalysts and excessive carbon emissions at high temperatures. However, the low-temperature DRM process still suffered from poor reactivity and severe catalyst deactivation from coking. Herein, we proposed a concept that highly durable DRM could be achieved at low temperatures via fabricating the active site integration with light irradiation. The active sites with Ni-O coordination (NiSA/CeO2) and Ni-Ni coordination (NiNP/CeO2) on CeO2, respectively, were successfully constructed to obtain two targeted reaction paths that produced the key intermediate (CH3O*) for anticoking during DRM. In particular, the operando diffuse reflectance infrared Fourier transform spectroscopy coupling with steady-state isotopic transient kinetic analysis (operando DRIFTS-SSITKA) was utilized and successfully tracked the anticoking paths during the DRM process. It was found that the path from CH3* to CH3O* over NiSA/CeO2 was the key path for anticoking. Furthermore, the targeted reaction path from CH3* to CH3O* was reinforced by light irradiation during the DRM process. Hence, the NiSA/CeO2 catalyst exhibits excellent stability with negligible carbon deposition for 230 h under thermo-photo catalytic DRM at a low temperature of 472 °C, while NiNP/CeO2 shows apparent coke deposition behavior after 0.5 h in solely thermal-driven DRM. The findings are vital as they provide critical insights into the simultaneous achievement of low-temperature and anticoking DRM process through distinguishing and directionally regulating the key intermediate species.

10.
Gastroenterology ; 163(4): 1079-1089.e5, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35788349

RESUMEN

BACKGROUND & AIMS: Magnetic resonance elastography (MRE) is an accurate biomarker of liver fibrosis; however, limited data characterize its association with clinical outcomes. We conducted an individual participant data pooled meta-analysis on patients with nonalcoholic fatty liver disease to evaluate the association between liver stiffness on MRE and liver-related outcomes. METHODS: A systematic search identified 6 cohorts of adults with nonalcoholic fatty liver disease who underwent a baseline MRE and were followed for hepatic decompensation, hepatocellular carcinoma, and death. Cox and logistic regression were used to assess the association between liver stiffness on MRE and liver-related outcomes, including a composite primary outcome defined as varices needing treatment, ascites, and hepatic encephalopathy. RESULTS: This individual participant data pooled meta-analysis included 2018 patients (53% women) with a mean (± standard deviation) age of 57.8 (±14) years and MRE at baseline of 4.15 (±2.19) kPa, respectively. Among 1707 patients with available longitudinal data with a median (interquartile range) of 3 (4.2) years of follow-up, the hazard ratio for the primary outcome for MRE of 5 to 8 kPa was 11.0 (95% confidence interval [CI]: 7.03-17.1, P < .001) and for ≥ 8 kPa was 15.9 (95% CI: 9.32-27.2, P < .001), compared with those with MRE <5 kPa. The MEFIB index (defined as positive when MRE ≥3.3 kPa and Fibrosis-4 ≥1.6) had a robust association with the primary outcome with a hazard ratio of 20.6 (95% CI: 10.4-40.8, P < .001) and a negative MEFIB had a high negative predictive value for the primary outcome, 99.1% at 5 years. The 3-year risk of incident hepatocellular carcinoma was 0.35% for MRE <5 kPa, 5.25% for 5 to 8 kPa, and 5.66% for MRE ≥8 kPa, respectively. CONCLUSION: Liver stiffness assessed by MRE is associated with liver-related events, and the combination of MRE and Fibrosis-4 has excellent negative predictive value for hepatic decompensation. These data have important implications for clinical practice.


Asunto(s)
Carcinoma Hepatocelular , Diagnóstico por Imagen de Elasticidad , Neoplasias Hepáticas , Enfermedad del Hígado Graso no Alcohólico , Adulto , Anciano , Biomarcadores , Carcinoma Hepatocelular/patología , Femenino , Fibrosis , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/patología , Neoplasias Hepáticas/patología , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/diagnóstico por imagen , Enfermedad del Hígado Graso no Alcohólico/patología
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