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1.
Circ Res ; 134(6): 635-658, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38484029

RESUMEN

Energetic demand and nutrient supply fluctuate as a function of time-of-day, in alignment with sleep-wake and fasting-feeding cycles. These daily rhythms are mirrored by 24-hour oscillations in numerous cardiovascular functional parameters, including blood pressure, heart rate, and myocardial contractility. It is, therefore, not surprising that metabolic processes also fluctuate over the course of the day, to ensure temporal needs for ATP, building blocks, and metabolism-based signaling molecules are met. What has become increasingly clear is that in addition to classic signal-response coupling (termed reactionary mechanisms), cardiovascular-relevant cells use autonomous circadian clocks to temporally orchestrate metabolic pathways in preparation for predicted stimuli/stresses (termed anticipatory mechanisms). Here, we review current knowledge regarding circadian regulation of metabolism, how metabolic rhythms are synchronized with cardiovascular function, and whether circadian misalignment/disruption of metabolic processes contribute toward the pathogenesis of cardiovascular disease.


Asunto(s)
Relojes Circadianos , Ritmo Circadiano , Corazón , Relojes Circadianos/fisiología , Sueño/fisiología , Miocardio/metabolismo
2.
Small ; : e2403852, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-39046073

RESUMEN

N-type PbSe thermoelectric materials encounter challenges in improving the power factor due to the single-band structure near the Fermi level, which obstructs typical band convergence. The primary strategy for enhancing the thermoelectric figure of merit (ZT) for n-type PbSe involves reducing lattice thermal conductivity (κlat) by introducing various defect structures. However, lattice mismatches resulting from internal defects within the matrix can diminish carrier mobility, thereby affecting electrical transport properties. In this study, n-type AgCuTe-alloyed PbSe systems achieve a peak ZT value of ≈1.5 at 773 K. Transmission electron microscopy reveals nanoprecipitates of Ag2Te, the room temperature second phase of AgCuTe, within the PbSe matrix. Meanwhile, a unique semi-coherent phase boundary is observed between the PbSe matrix and the Ag2Te nanoprecipitates. This semi-coherent phase interface effectively scatters low-frequency phonons while minimizing damage to carrier mobility. Additionally, the dynamic doping effect of Cu atoms from the decomposition of AgCuTe within the matrix further optimize the high-temperature thermoelectric performance. Overall, these factors significantly enhance the ZT across the whole temperature range. The ZT value of ≈1.5 indicates high competitiveness compared to the latest reported n-type PbSe materials, suggesting that these findings hold promise for advancing the development of efficient thermoelectric systems.

3.
Opt Express ; 32(9): 15065-15077, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859166

RESUMEN

Optical resonators made of 2D photonic crystal (PhC) slabs provide efficient ways to manipulate light at the nanoscale through small group-velocity modes with low radiation losses. The resonant modes in periodic photonic lattices are predominantly limited by nonleaky guided modes at the boundary of the Brillouin zone below the light cone. Here, we propose a mechanism for ultra-high Q resonators based on the bound states in the continuum (BICs) above the light cone that have zero-group velocity (ZGV) at an arbitrary Bloch wavevector. By means of the mode expansion method, the construction and evolution of avoided crossings and Friedrich-Wintgen BICs are theoretically investigated at the same time. By tuning geometric parameters of the PhC slab, the coalescence of eigenfrequencies for a pair of BIC and ZGV modes is achieved, indicating that the waveguide modes are confined longitudinally by small group-velocity propagation and transversely by BICs. Using this mechanism, we engineer ultra-high Q nanoscale resonators that can significantly suppress the radiative losses, despite the operating frequencies above the light cone and the momenta at the generic k point. Our work suggests that the designed devices possess potential applications in low-threshold lasers and enhanced nonlinear effects.

4.
Eur Radiol ; 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38488972

RESUMEN

OBJECTIVES: We aimed to develop machine learning (ML) models based on diffusion- and perfusion-weighted imaging fusion (DP fusion) for identifying stroke within 4.5 h, to compare them with DWI- and/or PWI-based ML models, and to construct an automatic segmentation-classification model and compare with manual labeling methods. METHODS: ML models were developed from multimodal MRI datasets of acute stroke patients within 24 h of clear symptom onset from two centers. The processes included manual segmentation, registration, DP fusion, feature extraction, and model establishment (logistic regression (LR) and support vector machine (SVM)). A segmentation-classification model (X-Net) was proposed for automatically identifying stroke within 4.5 h. The area under the receiver operating characteristic curve (AUC), sensitivity, Dice coefficients, decision curve analysis, and calibration curves were used to evaluate model performance. RESULTS: A total of 418 patients (≤ 4.5 h: 214; > 4.5 h: 204) were evaluated. The DP fusion model achieved the highest AUC in identifying the onset time in the training (LR: 0.95; SVM: 0.92) and test sets (LR: 0.91; SVM: 0.90). The DP fusion-LR model displayed consistent positive and greater net benefits than other models across a broad range of risk thresholds. The calibration curve demonstrated the good calibration of the DP fusion-LR model (average absolute error: 0.049). The X-Net model obtained the highest Dice coefficients (DWI: 0.81; Tmax: 0.83) and achieved similar performance to manual labeling (AUC: 0.84). CONCLUSIONS: The automatic segmentation-classification models based on DWI and PWI fusion images had high performance in identifying stroke within 4.5 h. CLINICAL RELEVANCE STATEMENT: Perfusion-weighted imaging (PWI) fusion images had high performance in identifying stroke within 4.5 h. The automatic segmentation-classification models based on DWI and PWI fusion images could provide clinicians with decision-making guidance for acute stroke patients with unknown onset time. KEY POINTS: • The diffusion/perfusion-weighted imaging fusion model had the best performance in identifying stroke within 4.5 h. • The X-Net model had the highest Dice and achieved performance close to manual labeling in segmenting lesions of acute stroke. • The automatic segmentation-classification model based on DP fusion images performed well in identifying stroke within 4.5 h.

5.
Int J Med Sci ; 21(7): 1204-1212, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38818479

RESUMEN

The mitochondrial unfolded protein response (UPRmt) is a pivotal cellular mechanism that ensures mitochondrial homeostasis and cellular survival under stress conditions. This study investigates the role of UPRmt in modulating the response of nasopharyngeal carcinoma cells to cisplatin-induced stress. We report that the inhibition of UPRmt via AEB5F exacerbates cisplatin cytotoxicity, as evidenced by increased lactate dehydrogenase (LDH) release and apoptosis, characterized by a surge in TUNEL-positive cells. Conversely, the activation of UPRmt with oligomycin attenuates these effects, preserving cell viability and reducing apoptotic markers. Immunofluorescence assays reveal that UPRmt activation maintains mitochondrial membrane potential and ATP production in the presence of cisplatin, countering the rise in reactive oxygen species (ROS) and inhibiting caspase-9 activation. These findings suggest that UPRmt serves as a cytoprotective mechanism in cancer cells, mitigating cisplatin-induced mitochondrial dysfunction and apoptosis. The data underscore the therapeutic potential of modulating UPRmt to improve the efficacy and reduce the side effects of cisplatin chemotherapy. This study provides a foundation for future research on the exploitation of UPRmt in cancer treatment, with the aim of enhancing patient outcomes by leveraging the cellular stress response pathways.


Asunto(s)
Apoptosis , Cisplatino , Mitocondrias , Especies Reactivas de Oxígeno , Respuesta de Proteína Desplegada , Humanos , Respuesta de Proteína Desplegada/efectos de los fármacos , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Cisplatino/farmacología , Cisplatino/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Neoplasias Nasofaríngeas/patología , Neoplasias Nasofaríngeas/tratamiento farmacológico , Neoplasias Nasofaríngeas/metabolismo , Carcinoma Nasofaríngeo/patología , Carcinoma Nasofaríngeo/tratamiento farmacológico , Carcinoma Nasofaríngeo/metabolismo , Carcinoma Nasofaríngeo/genética , Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos
6.
Artículo en Inglés | MEDLINE | ID: mdl-38978507

RESUMEN

In hypertrophic scars, the differentiation and migration of fibroblasts are influenced by the extracellular matrix microenvironment, which includes factors such as stiffness, restraint, and tensile force. These mechanical stresses incite alterations in cell behavior, accompanied by cytoskeletal protein reorganization. However, the role of nucleo-skeletal proteins in this context remains underexplored. In this study, we use a polyacrylamide hydrogel (PAA) to simulate the mechanical stress experienced by cells in scar tissue and investigate the impact of Emerin on cell behavior. We utilize atomic force microscopy (AFM) and RNA interference technology to analyze cell differentiation, migration, and stiffness. Our findings reveal that rigid substrates and cellular restriction elevate Emerin expression and diminish differentiation. Conversely, reducing Emerin expression leads to attenuated cell differentiation, where stiffness and constraining factors exert no notable influence. Furthermore, a softening of cells and an enhanced migration rate are also markedly observed. These observations indicate that variations in nuclear skeletal proteins, prompted by diverse matrix microenvironments, play a pivotal role in the pathogenesis of hypertrophic scars (HSs). This research offers novel insights and a reference point for understanding scar fibrosis formation mechanisms and preventing fibrosis.

7.
J Liposome Res ; : 1-13, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38563474

RESUMEN

ABSTACTThe medicinal properties of genetic drugs are highly dependent on the design of delivery systems. Ionizable cationic lipids are considered core materials in delivery systems. However, there has not yet been a widespread consensus on the relationship between the wide diversity of lipid structure design and gene delivery efficiency. The aims of the research work were to synthesize ionizable cholesterol derivatives (iChol-lipids) and to evaluate their potential applications as gene delivery vector. A series of iChol-lipids with different head groups were synthesized with carbamate bond spacer. The chemical structures were characterized by 1H NMR, MS, melting range, and pKa. The interactions between iChol-lipids and MALAT1-siRNA were studied by molecular dynamics simulations and compared with market available DC-Chol, which revealed that hydrogen bonds, salt-bridge, and electrostatic interaction were probably involved. The self-assemble behaviors of these lipids were intensively investigated and evaluated by dynamic laser scattering in the presence of different helper lipids and PEGylated lipids. Their plasmid binding ability, transfection efficiency, hemolytic toxicity, and cytotoxicity were fully studied. IZ-Chol-LNPs was proved to be highly potential to effectively complex with DNA, and endosome escape mechanisms mediated by proton sponge effect was verified by pH-sensitive fluorescence probe BCFL.

8.
BMC Oral Health ; 24(1): 962, 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39154183

RESUMEN

BACKGROUND: This study investigated the characteristics of Monson's sphere in Chinese young adult females with individual normal occlusion to provide a reference for oral rehabilitation in prosthodontic and orthodontic treatments. METHODS: Points at the dental cusps and incisal edges were selected from 51 digital mandibular dental models of Chinese young adult females (aged 18-22 years) with individual normal occlusion. Monson's spheres were fitted to the selected points based on the least-squares principle and the radii were calculated. The deviation of each selected point from its relative spherical surface was also calculated. The radii and deviations of these points were examined using conventional descriptive statistics and distributions of the most deviated points inside and outside the spheres were analyzed. RESULTS: The mean radius of Monson's sphere in Chinese young adult females was 79.60 ± 14.13 mm. The deviation of each selected point from its relative sphere surface was 0.38 ± 0.30 mm. The maximum deviations inside and outside the sphere were 0.93 ± 0.25 mm and 0.95 ± 0.30 mm, respectively. The most deviated points outside the spheres were mainly distributed at the distolingual cusps of the mandibular second permanent molars (31.37%), while those inside the spheres were mainly distributed at the mesiolingual cusps of the mandibular first permanent molars (45.10%). CONCLUSIONS: The radius of Monson's sphere in Chinese young adult females was smaller than the classic four-inch value suggested by Monson. Deviation was observed from all selected points to their Monson's sphere surface, with the most deviated points distributed primarily in the molar region.


Asunto(s)
Mandíbula , Modelos Dentales , Humanos , Femenino , Adulto Joven , Adolescente , Mandíbula/anatomía & histología , Oclusión Dental , Imagenología Tridimensional/métodos , China , Pueblos del Este de Asia
9.
BMC Oral Health ; 24(1): 629, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38807098

RESUMEN

BACKGROUND: In orthodontics, anterior open bite is a common malocclusion that recurs frequently. Because the causes of anterior open bite are so varied, medical professionals must create customized treatment programs for each patient based on their unique etiology. Through the lowering of the posterior teeth, closure of the anterior teeth gap, and cooperation with intermaxillary traction, the treatment plan outlined in this case study sought to achieve a stable occlusion. CASE PRESENTATION: This case report aims to describe an orthodontic camouflage treatment of a 15-year-old female patient with anterior open bite, arch width discrepancy and a history of temporomandibular joint disorder. The patient was treated with intermaxillary vertical elastics and the multiple edgewise arch wire (MEAW) approach. A satisfactory occlusion with a neutral molar relationship was attained after 29 months of orthodontic therapy. The condylography recording showed that this patient's occlusion tended to be more stable both before and after our treatment. The purpose of this case study is to provide an overview of an orthodontic camouflage treatment for a female patient, who had a history of temporomandibular joint disease, anterior open bite, and arch width disparity. CONCLUSIONS: Our results demonstrated that more attention should be paid to levelling the occlusal plane, intrusion of the molars, decompression of temporomandibular joints and the etiology factors of malocclusion during the orthodontic period for those patients with anterior open bite.


Asunto(s)
Mordida Abierta , Trastornos de la Articulación Temporomandibular , Humanos , Femenino , Adolescente , Mordida Abierta/terapia , Trastornos de la Articulación Temporomandibular/terapia , Ortodoncia Correctiva/métodos , Cefalometría , Planificación de Atención al Paciente
10.
Materials (Basel) ; 17(9)2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38730833

RESUMEN

Flow-accelerated corrosion (FAC) preferentially attacks the downstream heat-affected zone of the root-pass weld in steam pipe systems. A detailed characterization identifies the fusion boundary as the initiation location for the attack. Alloying elements are found depleted along the weld fusion boundary, and multiple welding thermal cycles and repetitive austenite-to-ferrite phase transformations result in an increased proportion of grains with Goss {110}<001> texture along the fusion boundary. The synergistic effects of chemical segregation and the Schmid factor may contribute to the preferential initiation of FAC cracks along the root weld fusion boundary, making it the weakest link for FAC attack in steam pipe girth welds.

11.
Curr Med Imaging ; 20: e15734056234694, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38087298

RESUMEN

Background: High-altitude pulmonary edema (HAPE) is a serious life-threatening disease that occurs after rapid ascent to high altitude; its main early-stage presentations include fatigue, headache, low-grade fever, dyspnea, and cough. X-ray and computed tomography (CT) images show pulmonary shadows and patches, which may be localized (initial right lung field predomination) or generalized to the bilateral lung base. Case Presentation: In this report, we present a case of a 25-year-old man diagnosed with HAPE combined with spontaneous pneumomediastinum. After a quick descent and effective medical treatment, this patient made a full recovery. The case may provide helpful information for the prevention and treatment of this disease since an increased number of people, especially young men, currently travel and work at high altitudes. Conclusion: After accurate clinical diagnosis with the help of CT or X-ray, immediate descent and appropriate oxygen supplementation are the most effective treatments for HAPE at high altitude.


Asunto(s)
Mal de Altura , Enfisema Mediastínico , Edema Pulmonar , Masculino , Humanos , Adulto , Altitud , Edema Pulmonar/diagnóstico por imagen , Edema Pulmonar/etiología , Enfisema Mediastínico/etiología , Enfisema Mediastínico/complicaciones , Mal de Altura/complicaciones , Mal de Altura/diagnóstico por imagen
12.
Rev Sci Instrum ; 95(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38557885

RESUMEN

Tikhonov regularization, or truncated singular value decomposition (TSVD), is usually used for dynamic light scattering (DLS) inversion of particles in suspension. The Tikhonov regularization method uses a regularization matrix to modify all singular values in the kernel matrix. The modification of large singular values cannot effectively reduce the variance of the estimated values but may introduce bias in the solution, resulting in poor disturbance resistance in the inversion results. The TSVD method, on the other hand, truncates all small singular values, which leads to the loss of particle size information during the inversion process. The shortcomings of the two methods mentioned above do not have a significant impact on the inversion of high signal-to-noise ratio data. However, compared to the classical DLS particle size inversion for non-flowing suspended particles, the DLS inversion of flowing aerosols is more significantly affected by noise, and the extraction of particle size information is more difficult due to the effect of flow velocity, resulting in worse inversion results with increasing aerosol flow velocity for both methods. To improve the accuracy of the particle size distribution (PSD) of flowing aerosols, we introduced a kernel matrix into the regularization matrix, and based on the principles of the two methods, the spectral information of the kernel matrix was utilized to make the modification of small singular values by the regularization matrix. Correspondingly, weak or no modification was made according to the values of large singular values to reduce the introduction of bias. The inversion results of simulated and measured data indicate that the reconstruction of the regularization matrix improves the anti-disturbance performance and avoids the loss of particle size information during the regularization inversion process, thereby significantly improving the PSD accuracy, which is affected by the dual effects of flow velocity and noise in the DLS measurement of flowing particles. The peak error and distribution error of the inversion results by reconstructing the regularization matrix are lower than those of Tikhonov regularization.

13.
Fitoterapia ; 174: 105860, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38367649

RESUMEN

PURPOSE: The aim of our research was to investigate the mechanism of the Hengqing II decoction in treating Alzheimer's disease (AD) through network pharmacology and experimental validation methods. METHODS: Firstly, the major chemical compounds of Hengqing II decoction were characterized by ultra-high-performance liquid chromatography-high resolution mass spectrometry (UHPLC-Q-TOF-MS/MS), and the gene sets related to AD treatment by Hengqing II decoction were collected through the database of PubChem, Swiss TargetPrediction, and DisGeNET. Secondly, a multi-level molecular network of "Traditional Chinese medicine (TCM)-compound-target-disease" was constructed and visualized using the STRING platform and Cytoscape 3.9.1 software, and the enrichment analysis based on the Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway databases was performed to predict the potential active compounds and targets of Hengqing II decoction for treating AD. Finally, molecular docking simulation was applied to investigate the binding interactions between potential active compounds and key targets, and the western blotting technique was employed to examine the expression levels of AKT1, TNF-α, and NOS2 proteins affected by active compounds. RESULTS: Totally 120 compounds in Hengqing II decoction were characterized by UHPLC-Q-TOF-MS/MS. Network pharmacology results showed that potential active compounds in Hengqing II decoction in treating AD included catalpol, gastrodin, and rehmannioside D, etc., and the main target proteins were TNF-α, NOS2, and AKT1. Further functional enrichment analysis revealed that Hengqing II decoction mainly exerted its therapeutic effects on AD by regulating lipid and atherosclerosis signaling pathways, AD signaling pathways, AKT1 signaling pathways, and PTGS2 signaling pathways. CONCLUSION: Hengqing II decoction exerted therapeutic effects on AD through multi-component, multi-target, and multi-pathway regulation, and its action mechanisms were related to oxidative stress, neuroinflammation, autophagy, and other pathways. Our research laid the data foundation for further exploration of action mechanism and clarification of clinical positioning and provided new ideas and clues in TCM formula research.


Asunto(s)
Enfermedad de Alzheimer , Medicamentos Herbarios Chinos , Humanos , Factor de Necrosis Tumoral alfa , Enfermedad de Alzheimer/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Farmacología en Red , Espectrometría de Masas en Tándem , Estructura Molecular , Medicamentos Herbarios Chinos/farmacología
14.
Indian J Orthop ; 58(3): 242-249, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38425821

RESUMEN

Introduction: We present a new surgical technique of Krackow suture combined with vertical Nice knot for the treatment of inferior patellar fractures and report the clinical results. Patients and Methods: Seventeen consecutive patients admitted with inferior patellar fractures over a 2-year period from June 2019 to February 2022 were prospectively enrolled. The AO classification was 34-A1. All patients underwent open reduction and fixation with Krackow sutures in combination with vertical Nice knot. Postoperative follow-up was performed for at least 1 year to evaluate knee function. Results: The mean age of seventeen patients was 53.2 ± 9.5 years (39-68 years), and all patients were followed up for more than 12 months. The operation time was 54.6 ± 7.7 min (42-68 min). No patients had nonunion, joint stiffness, and joint pain. All cases achieved bony union at an average of 9.9 ± 1.5 weeks (8-13 weeks) after surgery. At the last follow-up, there was no significant difference in range of motion between the injured knee (129.7 ± 3.3°, range 125-135°) and the unaffected knee (130.8 ± 3.8°, range 126-137°) (t = 0.28, P > 0.05). The mean Bostman score of the knee joint was 29.6 ± 0.7, including 15 excellent cases (88.2%) and two good case (11.8%). Conclusion: Krackow sutures combined with vertical Nice knots are stable and reliable in the treatment of inferior patellar fractures. Knee rehabilitation can be performed immediately after surgery and satisfactory knee function can be achieved. It is a safe, simple, and reliable alternative surgical method, and patients do not need to bear the secondary surgical injury of removing the internal fixation material. Therefore, it is suitable for the application of clinical promotion. Supplementary Information: The online version contains supplementary material available at 10.1007/s43465-023-01093-0.

15.
J Hazard Mater ; 467: 133726, 2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38341883

RESUMEN

Understanding of the environmental behaviors of microplastics is limited by a lack of knowledge about how photoaging influences biofilm formation on microplastics in soil. Here, original microplastics (OMPs) and photoaged-microplastics (AMPs) were incubated in soil to study the effect of photoaging on formation and characteristics of biofilm on the poly (butylene succinate) microplastics. Because photoaging decreased the hydrophobicity of the microplastic, the biomass of biofilm on the OMPs was nearly twice that on the AMPs in the early stage of incubation. However, the significance of the substrate on biomass in the biofilm declined as the plastisphere developed. The bacterial communities in the plastisphere were distinct from, and less diverse than, those in surrounding soil. The dominant genera in the OMPs and AMPs plastispheres were Achromobacter and Burkholderia, respectively, indicating that photoaging changed the composition of the bacterial community of biofilm at the genus level. Meantime, photoaging decreased the complexity and stability of the plastisphere bacterial community network. Results of Biolog ECO-microplate assays and functional prediction from amplicons showed that photoaging treatment enhanced the carbon metabolic capacity of the microplastic biofilm. This study provides new insights into the formation of plastispheres in soil.


Asunto(s)
Butileno Glicoles , Microbiota , Polímeros , Envejecimiento de la Piel , Biomasa , Microplásticos , Plásticos , Biopelículas , Suelo
16.
Chin Herb Med ; 16(2): 231-234, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38706828

RESUMEN

Objective: To isolate bioactive compounds from the endophytic fungus Fusarium sporotrichioides isolated from Rauwolfia yunnanensis, and investigate their pharmacological activities. Methods: The chemical constituents were isolated and purified by combining with ODS column chromatography, silica gel column chromatography and by performing semipreparative HPLC. Their structures were established on the basis of 1D NMR (1H-NMR and 13C-NMR) and 2D NMR (1H-1H COSY, HSQC, HMBC and NOESY), as well as HRESIMS and comparison with literature data. In addition, the absolute configuration of compound 1 was determined by calculated ECD data. Results: One previously undescribed tetracyclic triterpenoid derivative, named as integracide L (1), 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8,14-diene-2α,3ß,11ß-triol (2), 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8-momoene-2α,3ß,11ß-triol (3), 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8,14-diene-3ß,11ß-triol (4), and 12α-acetoxy-4,4-dimethyl-24-methylene-5α-cholesta-8-momoene-3ß,11ß-triol (5) were isolated from F. sporotrichioide. Moreover, compound 1 was rare tetracyclic triterpenoid with single methyl replacement at C-4 position. Conclusion: Compound 1 was a new tetracyclic triterpenoid isolated from the endophytic fungus F. sporotrichioides. In addition, compound 2 could inhibit the growth of three different human cancer cells significantly. Compounds 3 and 5 were found to possess better cytotoxic activities on HepG-2 cells than the other compounds, with IC50 values of (2.8 ± 0.1) and (6.3 ± 0.3) µmol/L respectively.

17.
Front Microbiol ; 15: 1336278, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38803375

RESUMEN

Introduction: The aim of this study was to investigate the effects of diets on the composition and function of rumen microbiome and metabolites in Sanhe heifers. Methods: Metagenomic and metabolomic analyses were performed using rumen fluid samples collected from Sanhe heifers (n = 20) with similar body weights and ages from grass-fed and grain-fed systems. Results: The grain-fed group exhibited more intensive rumen fermentation than the grass-fed group. However, the grass-fed group exhibited carbohydrate metabolism and methane production higher than that of the grain-fed group; these increases were observed as a higher abundance of various bacterial phyla (Firmicutes, Bacteroidetes, Actinobacteria, Lentisphaerae, and Verrucomicrobia), families (Lachnospiraceae, Eubacteriaceae, and Eggerthellaceae), and the archaeal family Methanobacteriaceae. A comparison of genes encoding carbohydrate-active enzymes, using Kyoto Encyclopedia of Genes and Genome profiles, revealed noteworthy differences in the functions of rumen microbiota; these differences were largely dependent on the feeding system. Conclusion: These results could help manipulate and regulate feed efficiency in Sanhe cattle.

18.
Food Res Int ; 191: 114699, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39059955

RESUMEN

Ascorbic acid (AsA) is an indicator of the nutritional value of freshly cut kiwifruit during storage at 4℃, and its degradation can be inhibited after ozone treatment (1 mg/L, 10 min). The aim of this study was to elucidate the regulatory mechanism affecting AsA metabolism in fresh-cut kiwifruit after ozone treatment. In this study, ozone treatment not only prevented the decrease in AsA/dehydroascorbic acid and delayed the accumulation of total soluble solids/titratable acidity, but also altered phytohormone levels differently. Transcriptomic profiling combined with cis-acting element and correlation analysis were performed to reveal that abscisic acid and salicylic acid synergistically delay AsA degradation under ozone-treatment conditions. Actinidia03760, encoding ascorbate peroxidase, could be specifically recognized by the bZIP transcription factor and is considered a key candidate gene for further research. Collectively, ozone treatment is a promising method for preserving AsA content and improving the nutrition of fresh-cut kiwifruit.


Asunto(s)
Actinidia , Ácido Ascórbico , Frutas , Perfilación de la Expresión Génica , Ozono , Reguladores del Crecimiento de las Plantas , Transducción de Señal , Actinidia/genética , Actinidia/química , Actinidia/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Frutas/metabolismo , Frutas/química , Frutas/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Transcriptoma , Ácido Salicílico , Ácido Abscísico/metabolismo
19.
PLoS One ; 19(2): e0289129, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38330003

RESUMEN

To further enhance the residual current detection capability of low-voltage distribution networks, an improved adaptive residual current detection method that combines variational modal decomposition (VMD) and BP neural network (BPNN) is proposed. Firstly, the method employs the envelope entropy as the adaptability function, optimizes the [k, ɑ] combination value of the VMD decomposition using the bacterial foraging-particle swarm algorithm (BFO-PSO), and utilizes the interrelation number R as the classification index with the Least Mean Square Algorithm (LMS) to classify, filter, and extract the effective signal from the decomposed signal. Then, the extracted signals are detected by BPNN, and the training data are utilized to predict the residual current signals. Simulation and experimental data demonstrate that the proposed algorithm exhibits strong robustness and high detection accuracy. With an ambient noise of 10dB, the signal-to-noise ratio is 16.3108dB, the RMSE is 0.4359, and the goodness-of-fit is 0.9627 after processing by the algorithm presented in this paper, which are superior to the Variational Modal Decomposition-Long Short-Term Memory (VMD-LSTM) and Normalized-Least Mean Square (N-LMS) detection methods. The results were also statistically analyzed in conjunction with the Kolmogorov-Smirnov test, which demonstrated significance at the experimental data level, indicating the high accuracy of the algorithms presented in this paper and providing a certain reference for new residual current protection devices for biological body electrocution.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Simulación por Computador , Entropía , Memoria a Largo Plazo
20.
Front Immunol ; 15: 1425443, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39104538

RESUMEN

T cells, as a major lymphocyte population involved in the adaptive immune response, play an important immunomodulatory role in the early stages of autoimmune diseases. Autophagy is a cellular catabolism mediated by lysosomes. Autophagy maintains cell homeostasis by recycling degraded cytoplasmic components and damaged organelles. Autophagy has a protective effect on cells and plays an important role in regulating T cell development, activation, proliferation and differentiation. Autophagy mediates the participation of T cells in the acquired immune response and plays a key role in antigen processing as well as in the maintenance of T cell homeostasis. In autoimmune diseases, dysregulated autophagy of T cells largely influences the pathological changes. Therefore, it is of great significance to study how T cells play a role in the immune mechanism of autoimmune diseases through autophagy pathway to guide the clinical treatment of diseases.


Asunto(s)
Enfermedades Autoinmunes , Autofagia , Linfocitos T , Humanos , Autofagia/inmunología , Enfermedades Autoinmunes/inmunología , Animales , Linfocitos T/inmunología , Activación de Linfocitos/inmunología
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