RESUMEN
Numerous electrochemistry reactions require the precise calculation of the ion solvation energy. Despite the significant progress in the first-principles calculations for crystals and defect formation energies for solids, the liquid system free energy calculations still face many challenges. Ion solvation free energies can be calculated via different semiempirical ways, e.g., using implicit solvent models or cluster of explicit molecule models; however, systematically improving these models is difficult due to their lack of a solid theoretical base. A theoretically sound approach for calculating the free energy is to use thermodynamic integration. Nevertheless, owing to the difficulties of self-consistent convergence in first-principles calculations for unphysical atomic configurations, the computational alchemy approach has not been widely used for first-principles calculations. This study proposes a general approach to use first-principles computational alchemy for calculating the ion solvation energy. This approach is also applicable for other small molecules. The calculated ion solvation free energies for Li+, Na+, K+, Be2+, Mg2+, and Ca2+ are close to the experimental results, and the standard deviation due to molecular dynamics fluctuations is within 0.06 eV.
RESUMEN
INTRODUCTION: In the event of radiological accidents and cancer radiotherapies in the clinic, the gastrointestinal (GI) system is vulnerable to ionizing radiation and shows GI injury. Accessible biomarkers may provide means to predict, evaluate, and treat GI tissue damage. The current study investigated radiation GI injury biomarkers in rat plasma. MATERIAL AND METHODS: High-coverage targeted lipidomics was employed to profile lipidome perturbations at 72 h after 0, 1, 2, 3, 5, and 8 Gy (60Co γ-rays at 1 Gy/min) total-body irradiation in male rat jejunum. The results were correlated with previous plasma screening outcomes. RESULTS: In total, 93 differential metabolites and 28 linear dose-responsive metabolites were screened in the jejunum. Moreover, 52 lipid species with significant differences both in jejunum and plasma were obtained. Three lipid species with linear dose-response relationship both in jejunum and plasma were put forth, which exhibited good to excellent sensitivity and specificity in triaging different exposure levels. DISCUSSION: The linear dose-effect relationship of lipid metabolites in the jejunum and the triage performance of radiation GI injury biomarkers in plasma were studied for the first time. CONCLUSION: The present study can provide insights into expanded biomarkers of IR-mediated GI injury and minimally invasive assays for evaluation.
Asunto(s)
Lipidómica , Irradiación Corporal Total , Animales , Biomarcadores/metabolismo , Rayos gamma , Lípidos , Masculino , RatasRESUMEN
Rapid early triage and dose estimation is vital for limited medical resource allocation and treatment of a large number of the wounded after radiological accidents. Lipidomics has been utilized to delineate biofluid lipid signatures after irradiation. Here, high-coverage targeted lipidomics was employed to screen radiosensitive lipids after 0, 1, 2, 3, 5, and 8 Gy total body irradiation at 4, 24, and 72 h postirradiation in rat plasma. Ultra-performance liquid chromatography-tandem mass spectrometry with a multiple reaction monitoring method was utilized. In total, 416 individual lipids from 18 major classes were quantified and those biomarkers altered in a dose-dependent manner constituted panel A-panel D. Receiver operator characteristic curve analysis using combined lipids showed good to excellent sensitivity and specificity in triaging different radiation exposure levels (area under curve = 0.814-1.000). The equations for dose estimation were established by stepwise regression analysis for three time points. A novel strategy for radiation early triage and dose estimation was first established and validated using panels of lipids. Our study suggests that it is feasible to acquire quantitative lipid biomarker panels using targeted lipidomics platforms for rapid, high-throughput triage, which can provide further insights in developing lipidomics strategies for radiation biodosimetry in humans.
Asunto(s)
Lipidómica , Exposición a la Radiación , Animales , Lípidos , Plasma , Ratas , TriajeRESUMEN
The surface of an electrocatalyst undergoes dynamic chemical and structural transformations under electrochemical operating conditions. There is a dynamic exchange of metal cations between the electrocatalyst and electrolyte. Understanding how iron in the electrolyte gets incorporated in the nickel hydroxide electrocatalyst is critical for pinpointing the roles of Fe during water oxidation. Here, we report that iron incorporation and oxygen evolution reaction (OER) are highly coupled, especially at high working potentials. The iron incorporation rate is much higher at OER potentials than that at the OER dormant state (low potentials). At OER potentials, iron incorporation favors electrochemically more reactive edge sites, as visualized by synchrotron X-ray fluorescence microscopy. Using X-ray absorption spectroscopy and density functional theory calculations, we show that Fe incorporation can suppress the oxidation of Ni and enhance the Ni reducibility, leading to improved OER catalytic activity. Our findings provide a holistic approach to understanding and tailoring Fe incorporation dynamics across the electrocatalyst-electrolyte interface, thus controlling catalytic processes.
RESUMEN
Engineering high-performance electrocatalysts is of great importance for energy conversion and storage. As an efficient strategy, element doping has long been adopted to improve catalytic activity, however, it has not been clarified how the valence state of dopant affects the catalytic mechanism and properties. Herein, it is reported that the valence state of a doping element plays a crucial role in improving catalytic performance. Specifically, in the case of iridium doped nickel-iron layer double hydroxide (NiFe-LDH), trivalent iridium ions (Ir3+ ) can boost hydrogen evolution reaction (HER) more efficiently than tetravalent iridium (Ir4+ ) ions. Ir3+ -doped NiFe-LDH delivers an ultralow overpotential (19 mV @ 10 mA cm-2 ) for HER, which is superior to Ir4+ doped NiFe-LDH (44 mV@10 mA cm-2 ) and even commercial Pt/C catalyst (40 mV@ 10 mA cm-2 ), and reaches the highest level ever reported for NiFe-LDH-based catalysts. Theoretical and experimental analyses reveal that Ir3+ ions donate more electrons to their neighboring O atoms than Ir4+ ions, which facilitates the water dissociation and hydrogen desorption, eventually boosting HER. The same valence-state effect is found for Ru and Pt dopants in NiFe-LDH, implying that chemical valence state should be considered as a common factor in modulating catalytic performance.
RESUMEN
23,24-Dihydrocucurbitacin B (designated as C95 in this article) is a cucurbitane triterpenoid that has been shown to possess a variety of pharmacological activities, such as anti-inflammatory and anti-HIV-1 activities etc. In this study, we investigated the effects of 23,24-dihydrocucurbitacin B on lipid regulation. We showed that 23,24-dihydrocucurbitacin B (1-5 µM) dose-dependently promoted DiI-LDL uptake in HepG2 cells by upregulating low-density lipoprotein receptor (LDLR) protein. In HepG2 cells, 23,24-dihydrocucurbitacin B (1-10 µM) dose-dependently enhanced LDLR promoter activity by elevating the mature form of SREBP2 (sterol regulatory element binding protein 2) protein levels on one hand, and inhibited PCSK9 (proprotein convertase subtilisin/kexin type 9) promoter activity by attenuating HNF1α (hepatocyte nuclear factor-1α) protein levels in nuclei on the other hand. Consequently, the expression of LDLR protein markedly increased, whereas the PCSK9-mediated LDLR protein degradation decreased. In a high-cholesterol LVG golden Syrian Hamster model, administration of 23,24-dihydrocucurbitacin B (30 mg · kg-1â d-1, intragastric, for 3 weeks) significantly decreased the serum LDL-cholesterol (LDL-C) levels. PCSK9 protein levels in the serum and liver tissues were significantly decreased, whereas LDLR protein levels in liver tissues were significantly increased in the treated animals as compared with the control animals. In conclusion, our study demonstrates for the first time that 23,24-dihydrocucurbitacin B exhibits dual transcriptional regulation of LDLR and PCSK9 in HepG2 cells by increasing SREBP2 protein levels and decreasing HNF1α protein levels in the nuclei. These results propose a new strategy to simultaneously manage LDLR and PCSK9 protein expression and provide a promising lead compound for drug development.
Asunto(s)
Inhibidores de PCSK9 , Receptores de LDL/metabolismo , Triterpenos/farmacología , Administración Oral , Animales , Supervivencia Celular/efectos de los fármacos , Cricetinae , Relación Dosis-Respuesta a Droga , Células Hep G2 , Humanos , Metabolismo de los Lípidos/efectos de los fármacos , Conformación Molecular , Raíces de Plantas/química , Proproteína Convertasa 9/genética , Proproteína Convertasa 9/metabolismo , Receptores de LDL/genética , Relación Estructura-Actividad , Trichosanthes/química , Triterpenos/administración & dosificación , Triterpenos/aislamiento & purificación , Células Tumorales CultivadasRESUMEN
Developing highly efficient and low-cost photocatalysts for overall water splitting has long been a pursuit for converting solar power into clean hydrogen energy. Herein, we demonstrate that a nonstoichiometric nickel-cobalt double hydroxide can achieve overall water splitting by itself upon solar light irradiation, avoiding the consumption of noble-metal co-catalysts. We employed an intensive laser to ablate a NiCo alloy target immersed in alkaline solution, and produced so-called L-NiCo nanosheets with a nonstoichiometric composition and O2- /Co3+ ions exposed on the surface. The nonstoichiometric composition broadens the band gap, while O2- and Co3+ ions boost hydrogen and oxygen evolution, respectively. As such, the photocatalyst achieves a H2 evolution rate of 1.7â µmol h-1 under AMâ 1.5G sunlight irradiation and an apparent quantum yield (AQE) of 1.38 % at 380â nm.
RESUMEN
The electroreduction of carbon dioxide (CO2 ) toward high-value fuels can reduce the carbon footprint and store intermittent renewable energy. The iodide-ion-assisted synthesis of porous copper (P-Cu) microspheres with a moderate coordination number of 7.7, which is beneficial for the selective electroreduction of CO2 into multicarbon (C2+ ) chemicals is reported. P-Cu delivers a C2+ Faradaic efficiency of 78 ± 1% at a potential of -1.1 V versus a reversible hydrogen electrode, which is 32% higher than that of the compact Cu counterpart and approaches the record (79%) reported in the same cell configuration. In addition, P-Cu shows good stability without performance loss throughout a continuous operation of 10 h.
RESUMEN
Magnesium lithospermate B (MLB) is an active component of Salvia miltiorrhiza Radix, a traditional Chinese herb used in treating cardiovascular diseases. In this study, we investigated the protective effects of MLB against inflammation-induced endothelial dysfunction in vitro and in vivo, and the underlying mechanisms. Endothelial dysfunction was induced in human dermal microvascular endothelial cells (HMEC-1) in vitro by lipopolysaccharide (LPS, 1 µg/mL). We showed that pretreatment with MLB (10-100 µM) dose-dependently inhibited LPS-induced upregulation of inflammatory cytokines ICAM1, VCAM1, and TNFα, which contributed to reduced leukocytes adhesion and attenuation of endothelial hyperpermeability in HMEC-1 cells. SD rats were injected with LPS (10 mg/kg, ip) to induce endothelial dysfunction in vivo. We showed that pretreatment with MLB (25-100 mg/kg, ip) dose-dependently restored LPS-impaired endothelial-dependent vasodilation in superior mesenteric artery (SMA), attenuated leukocyte adhesion in mesenteric venules and decreased vascular leakage in the lungs. We further elucidated the mechanisms underlying the protective effects of MLB, and revealed that MLB pretreatment inhibited NF-κB activation through inhibition of IκBα degradation and subsequent phosphorylation of NF-κB p65 in vitro and in vivo. In HMEC-1 cells, MLB pretreatment activated the nuclear factor erythroid-2-related factor 2 (Nrf2) pathway. Knockdown of Nrf2 with siRNA abolished the inhibitory effects of MLB on IκBα degradation and ICAM1 up-regulation, which were mimicked by PKC inhibition (Gö6983) or PI3K/Akt inhibition (LY294002). In summary, our results demonstrate that MLB inhibits NF-κB activation through PKC- and PI3K/Akt-mediated Nrf2 activation in HMEC-1 cells and protects against LPS-induced endothelial dysfunction in murine model of acute inflammation.
Asunto(s)
Antiinflamatorios/farmacología , Medicamentos Herbarios Chinos/farmacología , Endotelio Vascular/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Factor 2 Relacionado con NF-E2/metabolismo , Sustancias Protectoras/farmacología , Animales , Línea Celular , Citocinas/metabolismo , Células Endoteliales/efectos de los fármacos , Humanos , Inflamación/inducido químicamente , Lipopolisacáridos , Masculino , Arteria Mesentérica Superior/efectos de los fármacos , FN-kappa B/metabolismo , Ratas Sprague-Dawley , Vasodilatación/efectos de los fármacosRESUMEN
OBJECTIVE: There is a growing interest in the role of kynurenine pathway and tryptophan metabolites in the pathophysiology of depression. In the present study, the metabolism of tryptophan along the kynurenine pathway was analysed in a rat model of depression. METHODS: Kynurenic acid (KYNA) and 3-hydroxykynurenine (3-HK) were measured by high-performance liquid chromatography (HPLC) in prefrontal cortex (PFC) and frontal cortex (FC) in a rat model of depression, the Flinders Sensitive Line (FSL) and their controls, the Flinders Resistant Line (FRL) rats. In addition, KYNA was also measured in hippocampus, striatum and cerebellum. RESULTS: KYNA levels were reduced in the PFC of FSL rats compared with FRL rats, but did not differ with regard to the FC, hippocampus, striatum or cerebellum. 3-HK levels in PFC and FC, representing the activity of the microglial branch of the kynurenine pathway, did not differ between the FSL and FRL strains. CONCLUSION: Our results suggest an imbalanced metabolism of the kynurenine pathway in the PFC of FSL rats.
Asunto(s)
Trastorno Depresivo/metabolismo , Ácido Quinurénico/metabolismo , Quinurenina/análogos & derivados , Corteza Prefrontal/metabolismo , Triptófano/metabolismo , Animales , Cerebelo/metabolismo , Cromatografía Liquida , Cuerpo Estriado/metabolismo , Trastorno Depresivo/genética , Modelos Animales de Enfermedad , Hipocampo/metabolismo , Quinurenina/metabolismo , RatasRESUMEN
Myocardial dysfunction is an important manifestation of sepsis. Previous studies suggest that melatonin is protective against sepsis. In addition, activation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway has been reported to be beneficial in sepsis. However, the role of PI3K/Akt signaling in the protective effect of melatonin against sepsis-induced myocardial dysfunction remains unclear. Here, LY294002, a PI3K inhibitor, was used to investigate the role of PI3K/Akt signaling in mediating the effects of melatonin on sepsis-induced myocardial injury. Cecal ligation and puncture (CLP) surgery was used to establish a rat model of sepsis. Melatonin was administrated to rats intraperitoneally (30 mg/kg). The survival rate, measures of myocardial injury and cardiac performance, serum lactate dehydrogenase level, inflammatory cytokine levels, oxidative stress level, and the extent of myocardial apoptosis were assessed. The results suggest that melatonin administration after CLP surgery improved survival rates and cardiac function, attenuated myocardial injury and apoptosis, and decreased the serum lactate dehydrogenase level. Melatonin decreased the production of the inflammatory cytokines TNF-α, IL-1ß, and HMGB1, increased anti-oxidant enzyme activity, and decreased the expression of markers of oxidative damage. Levels of phosphorylated Akt (p-Akt), unphosphorylated Akt (Akt), Bcl-2, and Bax were measured by Western blot. Melatonin increased p-Akt levels, which suggests Akt pathway activation. Melatonin induced higher Bcl-2 expression and lower Bax expression, suggesting inhibition of apoptosis. All protective effects of melatonin were abolished by LY294002, the PI3K inhibitor. In conclusion, our results demonstrate that melatonin mitigates myocardial injury in sepsis via PI3K/Akt signaling activation.
Asunto(s)
Antioxidantes/farmacología , Cardiopatías/metabolismo , Corazón/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Melatonina/farmacología , Sepsis/complicaciones , Animales , Western Blotting , Modelos Animales de Enfermedad , Ecocardiografía , Ensayo de Inmunoadsorción Enzimática , Cardiopatías/inducido químicamente , Cardiopatías/tratamiento farmacológico , Etiquetado Corte-Fin in Situ , Masculino , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacosRESUMEN
AIM: Betulin is a pentacyclic triterpenoid isolated from the bark of yellow and white birch trees with anti-cancer and anti-malaria activities. In this study we examined the effects of betulin on atherosclerosis in apoE-/- mice and the underlying mechanisms. METHODS: Murine macrophage RAW264.7 cells and human monocyte-derived THP-1 cells were tested. Foam cell formation was detected with Oil Red O staining. Cholesterol efflux was assessed using [3H]-cholesterol efflux assay. The expression of ATP-binding cassette transporter A1 and G1 (ABCA1 and ABCG1) was examined using RT-PCR and Western-blotting. The ABCA1 promoter activity was evaluated using luciferase activity assay. Male apoE-/- mice fed on a high-fat-diet (HFD), and received betulin (20 and 40 mg·kg-1·d-1, ig) for 12 weeks. The macrophage content and ABCA1 expression in the aortic sinuses were evaluated with immunofluorescence staining. The hepatic, intestinal and fecal cholesterol were also analyzed in the mice. RESULTS: In RAW264.7 cells, betulin (0.1-2.5 µg/mL) dose-dependently ameliorated oxLDL-induced cholesterol accumulation and enhanced cholesterol efflux. In both RAW264.7 and THP-1 cells, betulin increased the expression of ABCA1 and ABCG1 via suppressing the transcriptional repressors sterol-responsive element-binding proteins (SREBPs) that bound to E-box motifs in ABCA1 promoter, whereas E-box binding site mutation markedly attenuated betulin-induced ABCA1 promoter activity. In HFD-fed apoE-/- mice, betulin administration significantly reduced lesions in en face aortas and aortic sinuses. Furthermore, betulin administration significantly increased ABCA1 expression and suppressed macrophage positive areas in the aortic sinuses. Moreover, betulin administration improved plasma lipid profiles and enhanced fecal cholesterol excretion in the mice. CONCLUSION: Betulin attenuates atherosclerosis in apoE-/- mice by promoting cholesterol efflux in macrophages.
Asunto(s)
Transportador 1 de Casete de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1/metabolismo , Anticolesterolemiantes/uso terapéutico , Apolipoproteínas E/genética , Aterosclerosis/tratamiento farmacológico , Triterpenos/uso terapéutico , Animales , Anticolesterolemiantes/farmacología , Aterosclerosis/metabolismo , Línea Celular , Colesterol/metabolismo , Humanos , Macrófagos/metabolismo , Masculino , Ratones , Proteínas de Unión a los Elementos Reguladores de Esteroles/antagonistas & inhibidores , Triterpenos/farmacología , Regulación hacia ArribaRESUMEN
Exposure to infections in early life is considered a risk-factor for developing schizophrenia. Recently we reported that a neonatal CNS infection with influenza A virus in mice resulted in a transient induction of the brain kynurenine pathway, and subsequent behavioral disturbances in immune-deficient adult mice. The aim of the present study was to investigate a potential role in this regard of kynurenic acid (KYNA), an endogenous antagonist at the glycine site of the N-methyl-D-aspartic acid (NMDA) receptor and at the cholinergic α7 nicotinic receptor. C57BL/6 mice were injected i.p. with neurotropic influenza A/WSN/33 virus (2400 plaque-forming units) at postnatal day (P) 3 or with L-kynurenine (2×200 mg/kg/day) at P7-16. In mice neonatally treated with L-kynurenine prepulse inhibition of the acoustic startle, anxiety, and learning and memory were also assessed. Neonatally infected mice showed enhanced sensitivity to D-amphetamine-induced (5 mg/kg i.p.) increase in locomotor activity as adults. Neonatally L-kynurenine treated mice showed enhanced sensitivity to D-amphetamine-induced (5 mg/kg i.p.) increase in locomotor activity as well as mild impairments in prepulse inhibition and memory. Also, D-amphetamine tended to potentiate dopamine release in the striatum in kynurenine-treated mice. These long-lasting behavioral and neurochemical alterations suggest that the kynurenine pathway can link early-life infection with the development of neuropsychiatric disturbances in adulthood.
Asunto(s)
Conducta Animal/efectos de los fármacos , Encéfalo/metabolismo , Ácido Quinurénico/metabolismo , Quinurenina/farmacología , Infecciones por Orthomyxoviridae/fisiopatología , Anfetamina/farmacología , Animales , Animales Recién Nacidos , Química Encefálica/efectos de los fármacos , Condicionamiento Psicológico/efectos de los fármacos , Dopamina/análisis , Dopaminérgicos/farmacología , Femenino , Virus de la Influenza A , Masculino , Ratones , Ratones Endogámicos C57BL , Actividad Motora/efectos de los fármacos , Infecciones por Orthomyxoviridae/metabolismoRESUMEN
OBJECTIVE: To explore the effect of levetiracetam combined with oxcarbazepine on the memory and cognitive function of adult patients with temporal lobe epilepsy. METHODS: This retrospective analysis included 91 adult patients with temporal lobe epilepsy treated at Xianyang Hospital from June 2020 to December 2022. Based on their medication regimen, patients were categorized into an observation group (n=51) receiving levetiracetam plus oxcarbazepine and a control group (n=40) receiving only levetiracetam. Both groups underwent 3 months of continuous treatment. Therapeutic efficacy, pre- and post-treatment memory function (assessed using the Clinical Memory Scale, CMS), cognitive function (evaluated with the Wechsler Adult Intelligence Scale-Revised in China, WAISRC), anxiety and depression levels (measured by the Hamilton Anxiety Scale, HAMA, and Hamilton Depression Scale, HAMD), as well as adverse reactions, were compared between the two groups. Independent factors influencing treatment efficacy were also analyzed. RESULTS: CMS and WAISRC scores significantly increased in both groups after treatment (both P=0.001), with the observation group showing more significant improvements than the control group (P=0.001). The improvements in HAMA and HAMD scores in the observation group were significantly better than the control group (all P<0.001). Adverse reaction occurrence showed no significant difference between the two groups (P>0.05). Prognostic analysis identified seizure frequency and treatment regimen as independent factors influencing efficacy. CONCLUSION: Levetiracetam combined with oxcarbazepine effectively improves cognitive dysfunction in adults with temporal lobe epilepsy, with superior efficacy to levetiracetam alone, and good safety.
RESUMEN
AIM: To investigate the efficacy of a new visual acuity (VA) screening method, the baby vision test for young children. METHODS: A total 105 eyes of 65 children aged 2-8y were included in the study. Acuity testing was conducted using a standardized recognition acuity chart (Snellen visual chart: at 3 m) and the baby vision model assessment. The baby vision device includes a screen, a near infrared camera and a computer. Children were seated at a measured distance of 33-40 cm from a display for testing. VA was estimated according to the highest resolution the children could follow. Decimal VA data were converted to logarithm of the minimum angle of resolution (logMAR) for statistical analysis. The VA results for each child were recorded and analyzed for consistency. RESULTS: The mean VA measured using the Snellen visual chart was 0.62±0.32, and that assessed using the baby vision test was 0.66±0.27. The 95% limit of agreement was -0.609 to 0.695, with 95.2% (100/105) plots within the 95% limits of agreement. VA values of the baby vision test were significantly correlated with those of the Snellen chart (R=0.274, P=0.005). CONCLUSION: The baby vision test can be used as a relatively reliable method for estimating VA in young children. This new acuity assessment might be a valid predictor of optotype-measured acuity later in preverbal children.
RESUMEN
Metabonomics is an important platform for investigating the metabolites of integrated living systems and their dynamic responses to changes caused by both endogenous and exogenous factors. A metabonomics strategy based on liquid chromatography-mass spectrometry/mass spectrometry in both positive and negative ion modes was applied to investigate the short-term and long-term stability of metabolites in plasma. Principal components analysis and ten types of identified metabolites were used to summarize the time-dependent change rules in metabolites systematically at different temperatures. The long-term stability of metabolites in plasma specimens stored at -80 °C for five years was also studied. Analysis of these subjects identified 36 metabolites with statistically significant changes in expression (p < 0.05) and found a kind of metabolite with a hundred-fold change. The stability of metabolites in blood at 4 °C for 24 h was also investigated. These studies show that a thorough understanding of the effects of metabolite stability are necessary for improving the reliability of potential biomarkers.
Asunto(s)
Análisis Químico de la Sangre , Metabolómica , Espectrometría de Masas en Tándem , Animales , Biomarcadores/sangre , Cromatografía Liquida , Masculino , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Temperatura , Factores de TiempoRESUMEN
A zinc-infiltration process was adopted to prepare silver-doped copper nanosheet arrays. The larger atomic radius of Ag introduces tensile stress, which lowers the electron density at the s-orbitals of Cu atoms and improves the adsorption capability for hydrogen atoms. As a catalyst for hydrogen evolution, these silver doped copper nanosheet arrays achieved a low overpotential of 103 mV at 10 mA cm-2 in 1 M KOH, which is 604 mV lower than that of pure copper foil.
RESUMEN
This study was aimed at exploring the application value of positron emission tomography (PET) + magnetic resonance imaging (MRI) technology based on convolutional neural network (CNN) in the biopsy and treatment of intracranial glioma. 35 patients with preoperatively suspicious gliomas were selected as the research objects. Their imaging images were processed using CNN. They were performed with the preoperative head MRI, fluorodeoxyglucose (FDG) PET, and ethylcholine (FECH) PET scans to construct the cancer tissue contours. In addition, the performance of CNN was evaluated, and the postoperative pathology of patients was analyzed. The results suggested that the CNN-based PET + MRI technology showed a recognition accuracy of 97% for images. Semiquantitative analysis was adopted to analyze the standard uptake value (SUV). It was found that the SUVFDG and SUVFECH of grade II/III glioma were 9.77 ± 4.87 and 1.82 ± 0.50, respectively, and the SUVFDG and SUVFECH of grade IV glioma were 13.91 ± 1.83 and 3.65 ± 0.34, respectively. According to FDG PET, the mean value of SUV on the lesion side of grade IV glioma was greater than that of grade II-III glioma, and the difference was significant (P < 0.05), and similar results were obtained on FECH PET. It showed that CNN-based PET + MRI fusion technology can effectively improve the recognition effect of glioma, can more accurately determine the scope of glioma lesions, and can predict the degree of malignant glioma to a certain extent.
Asunto(s)
Neoplasias Encefálicas , Glioma , Algoritmos , Inteligencia Artificial , Biopsia , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/patología , Fluorodesoxiglucosa F18 , Glioma/diagnóstico por imagen , Glioma/patología , Humanos , Imagen por Resonancia Magnética/métodos , Tomografía de Emisión de Positrones/métodos , RadiofármacosRESUMEN
OBJECTIVE: To analyze the changes of carbohydrate antigen 153 (CA15-3), S-100 calcium-binding protein B (S100B) and insulin-like growth factor-1 (IGF-1) in the treatment of patients with high-grade glioma and their predictive value for efficacy. METHODS: In this retrospective the PG and CG study, 74 patients with glioma who were treated in the Affiliated Hospital of Yan'an University from January 2015 to January 2017 were labeled as the patient group (PG); the other 70 patients who underwent craniocerebral trauma surgery during the same period were selected as the control group (CG). The expressions of CA15-3, S100B and IGF-1 in the PG and CG were compared. The relationship between CA15-3, S100B, IGF-1, and the pathologic data of patients was analyzed. The expression differences of CA15-3, S100B, and IGF-1 were compared between low-grade glioma patients and high-grade glioma patients and their diagnostic value was analyzed. The values of CA15-3, S100B, and IGF-1 expression for predicting treatment efficacy were analyzed. RESULTS: Expressions of CA15-3, S100B, and IGF-1 in glioma patients were markedly higher than those in the CG (P<0.0001). The proportion of grade III+IV patients with high expression of CA15-3, S100B, and IGF-1 was higher than in grade II patients (P<0.05), and the expressions of CA15-3, S100B and IGF-1 in low-grade glioma patients were lower than in high-grade glioma (P<0.01). The AUCs of CA15-3, S100B, and IGF-1 in differentiating different grades of glioma were 0.822, 0.722, and 0.768, respectively. Serum CA15-3, S100B and IGF-1 levels of the patients after treatment were significantly lower than those before treatment (P<0.0001). With the deterioration of clinical efficacy, serum levels of CA15-3, S100B, and IGF-1 gradually increased (P<0.05), and CA15-3, S100B and IGF-1 were positively correlated with therapeutic efficacy (P<0.05). AUCs of CA15-3, S100B, and IGF-1 for predicting the clinical efficacy in glioma patients were 0.824, 0.741, and 0.800, respectively. CONCLUSION: CA15-3, S100B, and IGF-1 are highly expressed in patients with glioma. They are diagnostic indicators to distinguish patients with high-grade glioma, and have predictive value for treatment efficacy.
RESUMEN
This research aimed to discuss the characteristics of benign paroxysmal positional vertigo (BPPV) and the correlation with cerebrovascular disease. An artificial intelligence algorithm under a parallel dual-domain concatenated convolutional neural network (PDDC-CNN) was proposed to process the images of magnetic resonance imaging (MRI). MRI, magnetic resonance angiography (MRA), and susceptibility weighted imaging (SWI) were performed on all 60 research objects with a 3.0 MRI scanner. The number of cases with cerebral microbleeds (CMBs), SWI image display of small veins, the number of lacunar infarctions, vertebral artery dominance, and vertebrobasilar morphology were observed in the two groups. The number of lacunar infarctions was 2.400 ± 3.358 and 0.672 ± 0.251, respectively, in the BBPV group with 30 cases and the control group with the other 30 cases. The positive rates of CMBs on SWI images were 48% and 27% in the BBPV group and the control group, respectively, and the average CMBs were counted as 1.670 ± 2.326 and 0.487 ± 0.865. CMBs were shown as round or oval lesions of conventional sequence deletion in the images with a diameter of less than 1.5 cm. SWI images of the BBPV group showed a significant increase in intracerebral small veins compared to those of the control group. The curvature of the vertebrobasilar artery in the BBPV group was significantly higher than that in the control group, and the curvature of the basilar artery was slightly higher than that in the control group. In conclusion, the MRI features of BPPV patients were related to their own microvascular lesions closely, and it was speculated that the cerebrovascular factors might play a dominant role in the early onset of BPPV.