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1.
Neuroimage ; 290: 120566, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38467345

RESUMEN

OBJECTIVES: Many studies have investigated aberrant functional connectivity (FC) using resting-state functional MRI (rs-fMRI) in subjective tinnitus patients. However, no studies have verified the efficacy of resting-state FC as a diagnostic imaging marker. We established a convolutional neural network (CNN) model based on rs-fMRI FC to distinguish tinnitus patients from healthy controls, providing guidance and fast diagnostic tools for the clinical diagnosis of subjective tinnitus. METHODS: A CNN architecture was trained on rs-fMRI data from 100 tinnitus patients and 100 healthy controls using an asymmetric convolutional layer. Additionally, a traditional machine learning model and a transfer learning model were included for comparison with the CNN, and each of the three models was tested on three different brain atlases. RESULTS: Of the three models, the CNN model outperformed the other two models with the highest area under the curve, especially on the Dos_160 atlas (AUC = 0.944). Meanwhile, the model with the best classification performance highlights the crucial role of the default mode network, salience network, and sensorimotor network in distinguishing between normal controls and patients with subjective tinnitus. CONCLUSION: Our CNN model could appropriately tackle the diagnosis of tinnitus patients using rs-fMRI and confirmed the diagnostic value of FC as measured by rs-fMRI.


Asunto(s)
Mapeo Encefálico , Acúfeno , Humanos , Mapeo Encefálico/métodos , Acúfeno/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Encéfalo/diagnóstico por imagen , Redes Neurales de la Computación
2.
BMC Plant Biol ; 24(1): 686, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39026194

RESUMEN

BACKGROUND: In plants, the leaf functions as a solar panel, where photosynthesis converts carbon dioxide and water into carbohydrates and oxygen. In soybean, leaf type traits, including leaf shape, leaf area, leaf width, and leaf width so on, are considered to be associated with yield. In this study, we performed morphological characterization, transcriptome analysis, and endogenous hormone analysis of a rolled and narrow leaf mutant line (rl) in soybean. RESULTS: Compared with wild type HX3, mutant line rl showed rolled and narrower leaflet, and smaller leaf, meanwhile rl also performed narrower pod and narrower seed. Anatomical analysis of leaflet demonstrated that cell area of upper epidermis was bigger than the cell area of lower epidermis in rl, which may lead rolled and narrow leaf. Transcriptome analysis revealed that several cytokinin oxidase/dehydrogenase (CKX) genes (Glyma.06G028900, Glyma.09G225400, Glyma.13G104700, Glyma.14G099000, and Glyma.17G054500) were up-regulation dramatically, which may cause lower cytokinin level in rl. Endogenous hormone analysis verified that cytokinin content of rl was lower. Hormone treatment results indicated that 6-BA rescued rolled leaf enough, rescued partly narrow leaf. And after 6-BA treatment, the cell area was similar between upper epidermis and lower epidermis in rl. Although IAA content and ABA content were reduced in rl, but exogenous IAA and ABA didn't affect leaf type of HX3 and rl. CONCLUSIONS: Our results suggest abnormal cytokinin metabolism caused rolled and narrow leaf in rl, and provide valuable clues for further understanding the mechanisms underlying leaf development in soybean.


Asunto(s)
Perfilación de la Expresión Génica , Glycine max , Hojas de la Planta , Glycine max/genética , Glycine max/crecimiento & desarrollo , Glycine max/anatomía & histología , Glycine max/metabolismo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/anatomía & histología , Transcriptoma , Mutación , Regulación de la Expresión Génica de las Plantas , Reguladores del Crecimiento de las Plantas/metabolismo , Citocininas/metabolismo , Fenotipo
3.
Biomed Chromatogr ; 38(5): e5839, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38402638

RESUMEN

Resveratrol (Res) has been demonstrated to have beneficial effects on gouty nephropathy (GN). However, the mechanisms of Res on GN remain unclear. This study aimed to investigate the mechanisms of Res on GN. In this study, network pharmacology technology was used to predict the Res targets in the prevention and treatment of GN. Renal metabonomics was used to identify differential metabolites in kidney tissue of GN model rats. Finally, molecular docking technology was used to verify the binding ability of Res to key targets. Metabonomics analysis showed that 24 potentially important metabolites were involved in the prevention and treatment of GN with Res. After exposure to Res, metabolite levels normalized. The network pharmacology analysis showed that 24 key targets were involved in the prevention and treatment of GN disease. According to the metabolite-gene network diagram, we identified two core genes, PTGS1 and PTGS2, and found that both were involved in the arachidonic acid metabolism pathway. Molecular docking further verified the affinity of Res binding to PTGS1 and PTGS2. In conclusion, the mechanism of Res against GN may be the regulation of arachidonic acid metabolism through the regulation of PTGS 1 and PTGS 2.


Asunto(s)
Riñón , Proteínas de la Membrana , Metabolómica , Simulación del Acoplamiento Molecular , Farmacología en Red , Ratas Sprague-Dawley , Resveratrol , Animales , Resveratrol/farmacología , Resveratrol/química , Riñón/efectos de los fármacos , Riñón/metabolismo , Ratas , Metabolómica/métodos , Masculino , Ciclooxigenasa 2/metabolismo , Ciclooxigenasa 2/genética , Metaboloma/efectos de los fármacos , Ciclooxigenasa 1/metabolismo , Ciclooxigenasa 1/genética , Ciclooxigenasa 1/química , Gota/metabolismo , Gota/tratamiento farmacológico , Enfermedades Renales/metabolismo , Enfermedades Renales/tratamiento farmacológico
4.
Mikrochim Acta ; 191(10): 637, 2024 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-39349675

RESUMEN

Gold-platinum (Au@Pt) nanozymes with high catalytic activity and stability were designed to improve the stability of the enzyme-linked immunosorbent assay (ELISA), and a two-mode signal output was used to enhance the sensitivity and confidence of the assay. This study reports the two-mode signal output based on Au@Pt nanozyme to catalyzed 3,3',5,5'-tetramethylbenzidine (TMB) reaction. Oxidized 3,3',5,5'-tetramethylbenzidine (ox-TMB) has wide absorption spectrum, providing excellent optical density capabilities and fluorescence quenching. The detection limits of imidacloprid were 0.88 µg/L and 1.14 µg/L in colorimetric and fluorescence modes, respectively. Multiple-mode strategy improves detection accuracy, increases the confidence of experimental results, and broadens detection modes. Two modes can meet the requirements of accurate and flexible multi-mode sensing in different application situations.


Asunto(s)
Bencidinas , Colorimetría , Oro , Límite de Detección , Neonicotinoides , Nitrocompuestos , Platino (Metal) , Neonicotinoides/análisis , Nitrocompuestos/química , Nitrocompuestos/análisis , Platino (Metal)/química , Oro/química , Colorimetría/métodos , Bencidinas/química , Nanopartículas del Metal/química , Insecticidas/análisis , Catálisis , Espectrometría de Fluorescencia/métodos , Técnicas Biosensibles/métodos
5.
Wei Sheng Yan Jiu ; 53(1): 95-101, 2024 Jan.
Artículo en Zh | MEDLINE | ID: mdl-38443179

RESUMEN

OBJECTIVE: An analytical method was developed for tetrodotoxin(TTX) in urine by liquid chromatography-tandem mass spectrometry(LC-MS/MS) with internal standard calibration. METHODS: TTX in the sample was extracted with the mixture of acetic acid/methanol/acetonitrile(0.005 mL/0.8 mL/1.8 mL), cleaned by solid phase extraction(SPE) with cation exchange cartridge, eluted with 50% acetonitrile/water containing 0.3% hydrochloric acid, and neutralized with ammonia. The extract was separated by a Waters XBridge~(TM) BEH Amide column(150 mm×3.0mm, 1.7 µm) and measured by MS/MS. By optimizing sample extraction and SPE cleanup conditions, the problems of low recovery and strong suppression effects of MS signal for TTX in urine were resolved when cleaned with cation exchange cartridge. RESULTS: Quantitatively calibrated by the internal standard of Kasugamycin, good linear relationship was found for TTX in urine at the range of 0.2-200 µg/L with the correlation coefficient(r~2) of 0.997. The limits of detection and quantitation for TTX in sample matrix were 0.1 and 0.2µg/L, respectively. The average recoveries at three spiking levels(0.2, 10.0 and 200 µg/L) were 89.3%-95.3% with relative standard deviation(n=6) less than 5.1%. The concentrations of TTX in urine from 11 poisoning patients were 0.4-138 µg/L. The detection rate was 100% in urine collected within 3 days after poisoning. CONCLUSION: The established method was simple, accurate and sensitive. It can provide reliable technical support for the rapid treatment of TTX poisoning events and the study of toxin metabolism in vivo.


Asunto(s)
Espectrometría de Masas en Tándem , Humanos , Tetrodotoxina , Cromatografía Liquida , Calibración , Acetonitrilos , Cationes
6.
Zhongguo Zhong Yao Za Zhi ; 49(1): 224-231, 2024 Jan.
Artículo en Zh | MEDLINE | ID: mdl-38403355

RESUMEN

This study aims to reveal the effect of acteoside on gouty arthritis(GA) in rats based on liver metabolomics. The ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) was employed to search for the potential biomarkers and metabolic pathways. SD rats were randomly assigned into blank, model, colchicine(0.3 mg·kg~(-1)), and high-, medium-, low-dose(200, 100, and 50 mg·kg~(-1), respectively) acteoside groups(n=7). The rats were administrated once a day for 7 continuous days. Monosodium urate(MSU) was used to induce GA model in rats during administration. The degree of joint swelling and pathological changes of synovial tissue in rats were observed, and the levels of interleukin(IL)-1ß, IL-18 and tumor necrosis factor(TNF)-α in the synovial tissue of rats were measured. UPLC-Q-TOF-MS was employed to collect rat liver data, and Progenesis QI and EZ info were used for data analysis. Human Metabolomics Database(HMDB) and Kyoto Encyclopedia of Genes and Genomes(KEGG) were employed to predict the potential biomarkers and metabolic pathways. The results showed that acteoside alleviated joint swelling, reduced synovial tissue damage, and lowered the levels of inflammatory cytokines in GA rats. A total of 19 common biomarkers were identified, 17 of which can be regulated by acteoside. Seven metabolic pathways were enriched, such as glycerophospholipid metabolism, linoleic acid metabolism, and taurine and hypotaurine metabolism, among which glycerophospholipid metabolism was strongly disturbed. The metabolomics analysis suggested that acteoside may down-regulate the expression of inflammatory cytokines and alleviate the symptoms of GA rats by regulating glycerophospholipid metabolism, linoleic acid metabolism, and taurine and hypotaurine metabolism. The findings provide a reference for future research and development of acteoside.


Asunto(s)
Artritis Gotosa , Glucósidos , Polifenoles , Taurina/análogos & derivados , Humanos , Ratas , Animales , Artritis Gotosa/inducido químicamente , Artritis Gotosa/tratamiento farmacológico , Ácido Linoleico , Ratas Sprague-Dawley , Metabolómica , Hígado/metabolismo , Citocinas , Biomarcadores/metabolismo , Glicerofosfolípidos , Cromatografía Líquida de Alta Presión
7.
Neuroimage ; 284: 120475, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38013009

RESUMEN

Age-related hearing loss (ARHL), one of the most common sensory deficits in elderly individuals, is a risk factor for dementia; however, it is unclear how ARHL affects the decline in cognitive function. To address this issue, a connectome gradient framework was used to identify critical features of information integration between sensory and cognitive processing centers using resting-state functional magnetic resonance imaging (rs-fMRI) data from 40 individuals with ARHL and 36 healthy controls (HCs). The first three functional gradient alterations associated with ARHL were investigated at the global, network and regional levels. Using a support vector machine (SVM) model, our analysis distinguished individuals with ARHL with normal cognitive function from those with cognitive decline. Compared to HCs, individuals with ARHL had a contracted principal primary-to-transmodal gradient axis, especially in the visual and default mode networks, with an altered gradient explained ratio and variance. Among individuals with ARHL, cognitive decline was detected in the visual network in the principal gradient as well as in the limbic, salience and default mode networks in the third gradient (salience to frontoparietal/default mode). These results suggest that ARHL is associated with disrupted information processing from the primary sensory networks to higher-order cognitive networks and highlight the key nodes closely associated with cognitive decline during cognitive processing in ARHL, providing new insights into the mechanism of cognitive impairment and suggesting potential treatments related to ARHL.


Asunto(s)
Disfunción Cognitiva , Conectoma , Presbiacusia , Humanos , Anciano , Conectoma/métodos , Cognición , Factores de Riesgo , Imagen por Resonancia Magnética/métodos
8.
Neuroimage ; 283: 120421, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37879424

RESUMEN

Elevated impulsivity has been frequently reported in individuals with opioid addiction receiving methadone maintenance therapy (MMT), but the underlying neural mechanisms and cognitive subprocesses are not fully understood. We acquired functional magnetic resonance imaging (fMRI) data from 37 subjects with heroin addiction receiving long-term MMT and 33 healthy controls who performed a probabilistic reversal learning task, and measured their resting-state brain glucose using fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET). Subjects receiving MMT exhibited significantly elevated self-reported impulsivity, and computational modeling revealed a marked impulsive decision bias manifested as switching more frequently without available evidence. Moreover, this impulsive decision bias was associated with the dose and duration of methadone use, irrelevant to the duration of heroin use. During the task, the switch-related hypoactivation in the left rostral middle frontal gyrus was correlated with the impulsive decision bias while the function of reward sensitivity was intact in subjects receiving MMT. Using prior brain-wide receptor density data, we found that the highest variance of regional metabolic abnormalities was explained by the spatial distribution of µ-opioid receptors among 10 types of neurotransmitter receptors. Heightened impulsivity in individuals receiving prolonged MMT is manifested as atypical choice bias and noise in decision-making processes, which is further driven by deficits in top-down cognitive control, other than reward sensitivity. Our findings uncover multifaceted mechanisms underlying elevated impulsivity in subjects receiving MMT, which might provide insights for developing complementary therapies to improve retention during MMT.


Asunto(s)
Dependencia de Heroína , Humanos , Dependencia de Heroína/tratamiento farmacológico , Metadona/uso terapéutico , Heroína/efectos adversos , Encéfalo/diagnóstico por imagen , Conducta Impulsiva
9.
Eur J Neurosci ; 58(4): 3026-3036, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37337805

RESUMEN

Previous studies have suggested that the Papez circuit may be involved in the cognitive impairment observed after hearing loss in presbycusis patients, yet relatively little is known about the pattern of changes in effective connectivity within the circuit. The aim of this study was to investigate abnormal alterations in resting-state effective connectivity within the Papez circuit and their association with cognitive decline in presbycusis patients. The spectral dynamic causal modelling (spDCM) approach was used for resting-state effective connectivity analysis in 61 presbycusis patients and 52 healthy controls (HCs) within the Papez circuit. The hippocampus (HPC), mamillary body (MB), anterior thalamic nuclei (ATN), anterior cingulate cortex (ACC), posterior cingulate cortex (PCC), entorhinal cortex (ERC), subiculum (Sub) and parahippocampal gyrus (PHG) were selected as the regions of interest (ROIs). The fully connected model difference in effective connectivity between the two groups was assessed, and the correlation between effective connectivity alteration and cognitive scale was analysed. We found that presbycusis patients demonstrated decreased effective connectivity from MB, PCC, and Sub to ACC relative to HCs, whereas higher effective connectivity strength was shown from HPC to MB, from ATN to PHG and from PHG to Sub. The effective connectivity from PHG to Sub was significantly negatively correlated with the complex figure test (CFT)-delay score (rho = -0.259, p = 0.044). The results support and reinforce the role of abnormal effective connectivity within the Papez circuit in the pathophysiology of presbycusis-related cognitive impairment and reveal its potential as a novel imaging marker.

10.
Nutr Cancer ; 75(7): 1520-1530, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37177915

RESUMEN

This meta-analysis was conducted to systematically evaluate the prognostic role of the Naples prognostic score (NPS) in patients with gastrointestinal (GI) cancers. A comprehensive literature search of several major databases was performed for studies published until October 16, 2022. Hazard ratios (HRs) with 95% confidence intervals (CIs) were extracted and pooled by fixed-effects or random-effects models to analyze the associations between the NPS and overall survival (OS), cancer-specific survival (CSS), and recurrence-free/disease-free survival (RFS/DFS) in GI cancers. Thirteen studies were included in the meta-analysis. Pooled results indicated that a high NPS predicted poor OS (HR = 2.28, 95% CI: 1.90-2.74, p < 0.001), CSS (HR = 2.77, 95% CI: 2.10-3.66, p < 0.001), and RFS/DFS (HR = 2.77, 95% CI: 2.26-3.40, p < 0.001). For OS-related and RFS/DFS-related studies, subgroup analyses showed that a high NPS was significantly associated with poor OS and RFS/DFS irrespective of NPS group, calculation of the NPS, and tumor type. In the study that focused on CSS, subgroup analyses by NPS group and calculation of the NPS revealed similar results. The NPS may represent an effective prognostic indicator in patients with GI cancers.


Asunto(s)
Neoplasias Gastrointestinales , Humanos , Pronóstico , Supervivencia sin Enfermedad , Modelos de Riesgos Proporcionales
11.
Vox Sang ; 118(2): 138-146, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36534000

RESUMEN

BACKGROUND AND OBJECTIVES: Transfusion services in China must establish a quality management system, and regular inspection of quality indicators is an important component of quality management. Although the positive role of information technology in reducing human errors has been widely reported, its role in improving transfusion quality indicators still requires further study. This study explores the role of information technology in improving the quality of transfusion practice. MATERIALS AND METHODS: We developed an optimized blood transfusion management information system and then analysed the changes in four quality indicators before and after using the system to clarify the role of information technology in improving the quality of transfusion practice. RESULTS: After using the optimized system, the completeness rate for transfusion request forms increased from 81.5% to 99.3%; an unqualified doctor's signature was the most common incomplete content (0.45%). The appropriate transfusion rate increased from 87% to 99.4%, and red blood cell and frozen plasma utilization in most surgical departments decreased. Although the reporting rate for adverse transfusion reactions increased from 0.22% to 0.49%, these increases might be partly due to changes in transfusion regulations. The adequacy rate of transfusion medical records increased from 74.8% to 90.4%. Overall, the inadequacy of informed consent for transfusion, pre-transfusion laboratory tests and documentation of the transfusion process were reduced from 6.4%, 6.2% and 12.6% to 1.7%, 2.0% and 5.9%, respectively. CONCLUSION: Information technology can play an important role in improving the quality of transfusion practice, as part of a programme of medical education, regular audit and other measures.


Asunto(s)
Transfusión Sanguínea , Tecnología de la Información , Humanos , Consentimiento Informado , China
12.
BMC Womens Health ; 23(1): 401, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37528370

RESUMEN

OBJECTIVE: Advances in surgical techniques and perioperative management are the two major contributing factors to improved surgical outcomes. The purpose of the current study was to compare the efficacy of single-port surgery and perioperative enhanced recovery after surgery (ERAS) management in laparoscopic myomectomy. METHODS: The present study included 120 patients undergoing laparoscopic myomectomy in the Gynecological Ward of Quzhou Affiliated Hospital of Wenzhou Medical University. According to the traditional perioperative management mode and ERAS management, multi-port and single-port procedures, all patients were assigned to the Conventional-SPLS (Single-Port Laparoscopic Surgery with conventional perioperative care) group (n = 34), Conventional-Multi (multi-port laparoscopic surgery with conventional perioperative care) group (n = 47), and ERAS (multi-port laparoscopic surgery with ERAS perioperative care) group (n = 39). The surgical outcomes of the three groups were compared operation time, intraoperative blood loss, variations in postoperative hemoglobin, postoperative walking time, postoperative flatus expelling time, postoperative hospital stay, and visual analog scale (VAS) scores at 6 and 12 h following surgery. RESULTS: The ERAS group recovered the quickest in terms of postoperative walking time and flatus expelling duration. The ERAS group also recovered the shortest postoperative hospital stay (3.85 ± 1.14 days), which differed significantly from that in the Conventional-Multi group, but not significantly from that in the Conventional-SPLS group. In terms of VAS scores at 6 and 12 h after surgery, the ERAS group had the lowest pain intensity, which differed significantly from that of the other two groups. The effect of surgical procedures or postoperative care on hospital stay was assessed using multiple regression analysis. The results demonstrated that ERAS was an important independent contributor to reducing postoperative hospital stay (ß = 0.270, p = 0.002), while single-port surgery did not affect this index (ß = 0.107, p = 0.278). CONCLUSION: In laparoscopic myomectomy, perioperative ERAS management could control postoperative pain and shorten hospital stay. Single-port surgery could speed up the recovery of gastrointestinal function and postoperative walking time, but it did not affect postoperative pain management or the length of hospital stay. Thus, the most effective approach to improving postoperative outcomes in laparoscopic myomectomy was the application of perioperative ERAS management.


Asunto(s)
Recuperación Mejorada Después de la Cirugía , Laparoscopía , Miomectomía Uterina , Femenino , Humanos , Miomectomía Uterina/métodos , Flatulencia , Laparoscopía/métodos , Dolor Postoperatorio/prevención & control , Tiempo de Internación , Complicaciones Posoperatorias , Estudios Retrospectivos
13.
Artículo en Inglés | MEDLINE | ID: mdl-37883769

RESUMEN

Gouty arthritis (GA) cause great harm to patients. Cellular pyroptosis, a mode of programmed cell death associated with inflammatory response, is closely related to GA. Both cysteamine aspartate-1-dependent and non-dependent pathways are involved in the progression of GA. During GA development, high blood uric acid levels leads to excessive biologically-inspired NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasome activation to drive caspase-1 activation for promoting the maturation of interleukin-1ß precursors, and caspase-1 activation disrupts the amino terminus in gasdermin D-N (GSDMD-N) and carboxy-terminal gasdermin-C structural domains, causing pores in the membrane and thus inducing the onset of scorch death. Therefore, modulating the onset of scorch death may become an important target for drug intervention in diseases. Chinese medicine is substantially biologically inspired and used synergistically to treat GA through multiple pathways and targets, which may regulate the relevant pathways through cellular pyroptosis quality. This study focuses on the interpretable regulatory mechanism of cellular pyroptosis bionic in GA and the role of Chinese medicine on GA, which provides a new scientific basis and strategy for targeting cellular pyroptosis bionic as the prevention and treatment quality of GA.

14.
Sensors (Basel) ; 23(3)2023 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-36772336

RESUMEN

Fibre optic sensors offer a means for the real-time continuous measurement of temperature or strain in concrete structures. Backscattered light along a fibre optic sensing (FOS) cable is interrogated to record a frequency shift and this shift is typically translated into a physical parameter such as strain or temperature using a calibration factor. However, when the measured frequency shift is a response to a combination of mechanical, thermal or hygral (humidity) loadings it is difficult to decouple individual influences. This presents a challenge in complex materials such as concrete where the strain, temperature and moisture levels change concurrently during the fresh and hardened states. Furthermore, depending on the application, both short- and longer-term measurements are required. As such, not only is the influence of these physical factors of interest but also the time and spatial stability of the measured frequency, which is highly dependent on the FOS cable composition. To investigate this aspect, fibre optic cables commonly used for strain (three tight-buffered cables) or temperature (two loose-buffered cables) measurement were considered. The cables were subjected to mechanical or environmental exposure and interrogated using a high-resolution optical backscatter reflectometer. The exposure regimes included three temperature cycles with sustained steps from 10 °C to 60 °C and back to 10 °C and an increasing and decreasing humidity cycle with steps between 30 to 90% relH. These ranges were selected to be indicative of typical environments for concrete. The results showed that the calibration factors back-calculated from increasing and decreasing temperature or humidity cycles differed. The third temperature cycle results were found to exhibit the smallest differences between heating and cooling suggesting that temperature pre-conditioning prior to installation could be advantageous. For all the cables, a drift in the readings was observed over the duration (2.5 h for temperature and 30 h for moisture) of the sustained steps. The magnitude of the drift depended on the cable type and exposure condition. In addition, local frequency fluctuations along the cable were observed which would need to be taken into account if only a single point along the cable length was used for analysis. The obtained results highlight the importance of the cable selection to maximise the FOS measurement fidelity for a given parameter of interest.

15.
Nano Lett ; 22(3): 1207-1216, 2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35084869

RESUMEN

Flexible lithium-sulfur (Li-S) batteries with high mechanical compliance and energy density are highly desired. This manuscript reported that large-area freestanding MXene (Ti3C2Tx) film has been obtained through a scalable drop-casting method, significantly improving adhesion to the sulfur layer under the continuously bent. Titanium oxide anchored on holey Ti3C2Tx (TiO2/H-Ti3C2Tx) was also produced by the well-controlled oxidation of few-layer Ti3C2Tx, which greatly facilitates lithium ion transport as well as prevents the shuttling of lithium polysulfides. Therefore, the obtained sandwich electrode has demonstrated a high capacity of 740 mAh g-1 at 2 C and a high capacity retention of 81% at 1 C after 500 cycles. Flexible Li-S batteries based on this sandwich electrode have a capacity retention as high as 95% after bending 500 times. This work provides effective design strategies of MXene for flexible batteries and wearable electronics.

16.
Molecules ; 28(3)2023 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-36770789

RESUMEN

The harmful effects on the human body from p-phenylenediamine (PPD) in hair dyes can cause allergies and even cancer. Therefore, it is particularly important to accurately control and detect the content of PPD in our daily products and environment. Here, a small amount of non-metallic elemental P doped in perovskite oxide of SrCoO3-δ (SC) forms a good catalytic material, SrCo0.95P0.05O3-δ (SCP), for PPD detection. The improved performance compared with that of the parent SC can be attributed to three contributing factors, including a larger amount of highly oxidative oxygen species O22-/O-, better electrical conductivity, and more active sites on the P5+-oxygen bonds of SCP. Moreover, the lattice oxygen mechanism (LOM) with highly active species of lattice O vacancies and adsorbed -OO for electrocatalytic oxidation of PPD by the SCP/GCE (glass carbon electrode) sensor is proposed in our work. More importantly, the SCP/GCE sensor exhibits good stability, a low limit of detection, and high reliability (error < 5.78%) towards PPD determination in real samples of hair dyes, suggesting the substantial research potential for practical applications.

17.
Angew Chem Int Ed Engl ; 62(24): e202302844, 2023 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-37022339

RESUMEN

A peroxygenase-catalysed hydroxylation of organosilanes is reported. The recombinant peroxygenase from Agrocybe aegerita (AaeUPO) enabled efficient conversion of a broad range of silane starting materials in attractive productivities (up to 300 mM h-1 ), catalyst performance (up to 84 s-1 and more than 120 000 catalytic turnovers). Molecular modelling of the enzyme-substrate interaction puts a basis for the mechanistic understanding of AaeUPO selectivity.

18.
Mol Cancer ; 21(1): 63, 2022 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-35236349

RESUMEN

BACKGROUND: Circular RNAs (circRNAs) are differentially expressed between normal and cancerous tissues, contributing to tumor initiation and progression. However, comprehensive landscape of dysregulated circRNAs across cancer types remains unclear. METHODS: In this study, we conducted Ribo-Zero transcriptome sequencing on tumor tissues and their adjacent normal samples including glioblastoma, esophageal squamous cell carcinoma, lung adenocarcinoma, thyroid cancer, colorectal cancer, gastric cancer and hepatocellular carcinoma. CIRCexplorer2 was employed to identify circRNAs and dysregulated circRNAs and genes were determined by DESeq2 package. The expression of hsa_circ_0072309 (circLIFR) was measured by reverse transcription and quantitative real-time PCR, and its effect on cell migration was examined by Transwell and wound healing assays. The role of circLIFR in tumor metastasis was evaluated via mouse models of tail-vein injection and spleen injection for lung and liver metastasis, respectively. RESULTS: Distinct circRNA expression signatures were identified among seven types of solid tumors, and the dysregulated circRNAs exhibited cancer-specific expression or shared common expression signatures across cancers. Bioinformatics analyses indicated that aberrant expression of host genes and/or RNA-binding proteins contributed to circRNA dysregulation in cancer. Finally, circLIFR was experimentally validated to be downregulated in six solid tumors and to significantly inhibit cell migration in vitro and tumor metastasis in vivo. CONCLUSIONS: Our results provide a comprehensive landscape of differentially expressed circRNAs in solid tumors and highlight that circRNAs are extensively involved in cancer pathogenesis.


Asunto(s)
Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Animales , Movimiento Celular/genética , Biología Computacional/métodos , Humanos , Ratones , ARN/genética , ARN/metabolismo , ARN Circular/genética
19.
Small ; 18(10): e2105329, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35023622

RESUMEN

Nonprecious group metal (NPGM)-based single atom catalysts (SACs) hold a great potential in electrocatalysis and dopant engineering has been extensively exploited to boost their catalytic activity, while the coordination environment of dopant, which also significantly affects the electronic structure of SACs, and consequently their electrocatalytic performance, have been largely ignored. Here, by adopting a precursor modulation strategy, the authors successfully synthesize single cobalt atom catalysts embedded in nitrogen-doped carbon, Co-N/C, with similar overall Co and N concentrations but different N types, that is, pyridinic N (NP ), graphitic N (NG ), and pyrrolic N (NPY ). Co-N/C with the Co-N4 moieties coordinated with NG displays far superior activity for oxygen reduction (ORR) and evolution reactions, and superior activity and stability in both zinc-air batteries and proton exchange membrane fuel cells. Density functional theory calculation indicates that coordinated N species in particular NG functions as electron donors to the Co core of Co-N4 active sites, leading to the downshift of d-band center of Co-N4 and weakening the binding energies of the intermediates on Co-N4 sites, thus, significantly promoting catalytic kinetics and thermodynamics for ORR in a full pH range condition.

20.
Chembiochem ; 23(6): e202200017, 2022 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-35023279

RESUMEN

In this study, we developed a new bienzymatic reaction to produce enantioenriched phenylethanols. In a first step, the recombinant, unspecific peroxygenase from Agrocybe aegerita (rAaeUPO) was used to oxidise ethylbenzene and its derivatives to the corresponding ketones (prochiral intermediates) followed by enantioselective reduction into the desired (R)- or (S)-phenylethanols using the (R)-selective alcohol dehydrogenase (ADH) from Lactobacillus kefir (LkADH) or the (S)-selective ADH from Rhodococcus ruber (ADH-A). In a one-pot two-step cascade, 11 ethylbenzene derivatives were converted into the corresponding chiral alcohols at acceptable yields and often excellent enantioselectivity.


Asunto(s)
Alcohol Deshidrogenasa , Alcohol Feniletílico , Alcohol Deshidrogenasa/metabolismo , Derivados del Benceno , Oxigenasas de Función Mixta , Oxidación-Reducción , Estereoisomerismo
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