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1.
Food Sci Nutr ; 12(4): 2223-2239, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628201

RESUMO

A growing number of publications have shown that resveratrol has anticancer effects and has become a hotspot in cancer research. The purpose of this study is to analyze the academic results and research trends in resveratrol within the field of anticancer and to predict the future trends in this field. We conducted a literature search for resveratrol in anticancer research from 2003 to 2022 using the Science Citation Index Expanded of the Web of Science Core Collection. The visualization software was used to perform the bibliometric analysis. A total of 1463 publications from 2003 to 2022 were retrieved. China had the highest number of publications. Taipei Medical University became the research institution with the largest number of publications worldwide. The journals with the highest output and co-citation frequency were Molecules and Cancer Research. Levenson, Anait S and Jaeger, Walter published the largest number of papers. Jang, MS was the most co-cited author. Timeline View shows trends and relationship between research topics over time and suggests that the emerging frontier of resveratrol in anticancer may be "resveratrol induces apoptosis." As more and more evidence shows the important role of resveratrol in anticancer, further research on its mechanisms and target discovery may become a major direction for future research. The bibliometric analysis findings of this study will significantly contribute to scholars' comprehensive understanding of the anticancer effects and mechanisms of action of resveratrol, aiding in delineating research hotspots and frontier directions within this field, thereby providing guidance for future investigations.

2.
Value Health ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38608875

RESUMO

OBJECTIVES: Health-related Quality of Life (HRQoL) instruments for cardiovascular diseases (CVD) have been commonly used to measure important patient-reported outcomes (PROs) in clinical trials and practices. This study aimed at systematically identifying and assessing the content validity of CVD-specific HRQoL instruments in clinical studies. METHODS: The research team searched CINAHL, Embase, and PubMed from inception to January 20, 2022. The research team included studies that reported the development and content validity for CVD-specific instruments. Two reviewers independently assessed the methodological quality using the Consensus-based Standards for the Selection of Health Measurement Instruments (COSMIN) methods on evaluating content validity of PROs. Content analysis was used to categorize the items included in the instruments. RESULTS: The research team found 69 studies reporting the content validity of 40 instruments specifically developed for CVD. Fourteen (35.0%) were rated "sufficient" with very low to moderate quality of evidence. For PRO development, all instruments were rated "doubtful" or "inadequate". 28 (70.0%) instruments cover the core concepts of HRQoL. CONCLUSIONS: The quality of development and content validity vary among existing CVD-specific instruments. The evidence on the content validity should be considered when choosing a HRQoL instrument in CVD clinical studies and health economic evaluations.

3.
Adv Sci (Weinh) ; : e2400377, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561956

RESUMO

Ligand-protected heterometallic nanoclusters in contrast to homo-metal counterparts show more broad applications due to the synergistic effect of hetero-metals but their controllable syntheses remain a challenge. Among heterometallic nanoclusters, monovalent Ag-Cu compounds are rarely explored due to much difference of Ag(I) and Cu(I) such as atom radius, coordination habits, and redox potential. Encouraged by copper-catalyzed alkyne-azide cycloaddition (CuAAC) reaction, comproportionation reaction of Cu(II)X2 and Cu(0) in the presence of (PhC≡CAg)n complex and molybdate generated a core-shell peanut-shaped 66-nuclear Ag(I)-Cu(I) heterometallic nanocluster, [(Mo4O16)2@Cu12Ag54(PhC≡C)50] (referred to as Ag54Cu12). The structure and composition of Ag-Cu heterometallic nanocluster are fully characterized. X-ray single crystal diffraction reveals that Ag54Cu12 has a peanut-shaped silver(I)/copper(I) heterometallic nanocage protected by fifty phenylacetylene ligands in µ3-modes and encapsulated two mutually twisted tetramolybdates. Heterometallic nanocage contains a 54-Ag-atom outer ellipsoid silver cage decorated by 12 copper inside wall. Nanosized Ag54Cu12 is a n-type narrow-band-gap semiconductor with a good photocurrent response. Preliminary experiments demonstrates that Ag54Cu12 itself and activated carbon supported Ag54Cu12/C are effective catalysts for 1,3-dipole cycloaddition between alkynes and azides at ambient conditions. The work provides not only a new synthetic route toward Ag(I)-Cu(I) nanoclusters but also an important heterometallic intermediate in CuAAC catalytic reaction.

4.
Opt Express ; 32(7): 11886-11894, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571026

RESUMO

A polarization beam-splitting multimode filter using pixelated waveguides has been presented and experimentally demonstrated in this paper. Finite difference time domain method and direct binary search optimization algorithm are employed to optimize pixelated waveguides to realize compact size, broad bandwidth, large extinction ratio, low insertion loss, and good polarization extinction ratio. Measurement results show that, in a wavelength range from 1520 to 1560 nm, for the fabricated device working at transverse-electric polarization, the measured insertion loss is less than 1.23 dB and extinction ratio is larger than 15.14 dB, while for transverse-magnetic polarization, the corresponding insertion loss lower than 0.74 dB and extinction ratio greater than 15.50 dB are realized. The measured polarization extinction ratio larger than 15.02 dB is achieved. The device's length is only 15.4 µm.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38603540

RESUMO

Solar-blind photodetectors based on wide bandgap semiconductors have recently attracted a lot of interest. Nickel-containing spinel phase oxides, such as NiAl2O4, are stable p-type semiconductors. This paper describes a multifunctional solar-blind photodetector based on a NiAl2O4/4H-SiC heterojunction that utilizes photovoltaic effects. The position sensitivity reaches a value of 1589.7 mV/mm under 405 nm laser illumination, while the relaxation times of vertical photovoltaic (VPV) effect and lateral photovoltaic (LPV) effect under 266 nm laser illumination are only 0.32 and 0.42 µs, respectively. This junction was used to create a space optical communication system with sunlight having little effect on its optoelectronic properties. The ultrafast photovoltaic relaxation time makes NiAl2O4/4H-SiC a promising candidate for self-powered high-performance solar-blind detectors.

6.
Nat Commun ; 15(1): 3046, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589370

RESUMO

Sintering of active metal species often happens during catalytic reactions, which requires redispersion in a reactive atmosphere at elevated temperatures to recover the activity. Herein, we report a simple method to redisperse sintered Cu catalysts via O2-H2O treatment at room temperature. In-situ spectroscopic characterizations reveal that H2O induces the formation of hydroxylated Cu species in humid O2, pushing surface diffusion of Cu atoms at room temperature. Further, surface OH groups formed on most hydroxylable support surfaces such as γ-Al2O3, SiO2, and CeO2 in the humid atmosphere help to pull the mobile Cu species and enhance Cu redispersion. Both pushing and pulling effects of gaseous H2O promote the structural transformation of Cu aggregates into highly dispersed Cu species at room temperature, which exhibit enhanced activity in reverse water gas shift and preferential oxidation of carbon monoxide reactions. These findings highlight the important role of H2O in the dynamic structure evolution of supported metal nanocatalysts and lay the foundation for the regeneration of sintered catalysts under mild conditions.

7.
BMC Urol ; 24(1): 82, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594657

RESUMO

OBJECTIVES: Redo surgery for pelvic fracture urethral distraction defects (PFUDDs) is still a challenge. the long urethral defect makes it difficult while the high tension increase the recurrence rate. Although certain ancillary maneuvers can relieve tension, there is no consensus or guidelines for the prediction/planning of the selection. In this study, we present our experience with developing an intraoperative guidance system to achieve tension-free urethral anastomosis. PATIENTS AND METHODS: A total of 91 recurrent PFUDD patients managed at our center between 2020 and 2022 were retrospectively analyzed. The patients underwent scar removing and urethral anastomosis. For the long defect and high-tension cases, 6 kinds of tension-relieving maneuvers were used respectively during the process of urethral anastomosis. Preoperative assessment of the urethrogram was done before surgery, while biaxial (vertical and horizontal) defect measurements were performed intraoperatively. The patients were followed-up for 12 months (8.9 ± 4.2), furthermore, recurrence and complications were analyzed. RESULTS: The overall success rate was 86.81%. The mean defect in urethrogram was 2.9 ± 1.1 cm. 27 simple anastomosis was performed when the vertical plus horizontal defect was less than 2 cm with 11.11% recurrence. 24 cavernous septum splittings were performed when the horizontal defect was greater than 2 cm with 8.33% recurrence. 21 inferior pubectomies were performed when the horizontal defect was greater than 3 cm with 19.05% recurrence. 15 ancillary distal urethra manipulations (fully distal urethral mobilization, urethral suspension and corpus cavernosa folding) were performed when the vertical defect was 3 to 4 cm with 13.33 recurrence. 4 reroutings were performed when the vertical defect was greater than 4 cm with 25.00% recurrence. CONCLUSIONS: Ancillary maneuvers are effective for reducing tension in redo urethral anastomosis. Measurement of divergent vertical and horizontal urethral defects could guide the selection of ancillary maneuvers. Combined tension-relieving maneuvers is recommended according to the defect direction and length to achieve a tension-free anastomosis.


Assuntos
Fraturas Ósseas , Ossos Pélvicos , Estreitamento Uretral , Humanos , Uretra/cirurgia , Estudos Retrospectivos , Procedimentos Cirúrgicos Urológicos/efeitos adversos , Anastomose Cirúrgica/efeitos adversos , Fraturas Ósseas/complicações , Estreitamento Uretral/cirurgia , Resultado do Tratamento
8.
Respir Res ; 25(1): 173, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38643126

RESUMO

RATIONALE: Our understanding of airway dysbiosis in chronic obstructive pulmonary disease (COPD) remains incomplete, which may be improved by unraveling the complexity in microbial interactome. OBJECTIVES: To characterize reproducible features of airway bacterial interactome in COPD at clinical stability and during exacerbation, and evaluate their associations with disease phenotypes. METHODS: We performed weighted ensemble-based co-occurrence network analysis of 1742 sputum microbiomes from published and new microbiome datasets, comprising two case-control studies of stable COPD versus healthy control, two studies of COPD stability versus exacerbation, and one study with exacerbation-recovery time series data. RESULTS: Patients with COPD had reproducibly lower degree of negative bacterial interactions, i.e. total number of negative interactions as a proportion of total interactions, in their airway microbiome compared with healthy controls. Evaluation of the Haemophilus interactome showed that the antagonistic interaction networks of this established pathogen rather than its abundance consistently changed in COPD. Interactome dynamic analysis revealed reproducibly reduced antagonistic interactions but not diversity loss during COPD exacerbation, which recovered after treatment. In phenotypic analysis, unsupervised network clustering showed that loss of antagonistic interactions was associated with worse clinical symptoms (dyspnea), poorer lung function, exaggerated neutrophilic inflammation, and higher exacerbation risk. Furthermore, the frequent exacerbators (≥ 2 exacerbations per year) had significantly reduced antagonistic bacterial interactions while exhibiting subtle compositional changes in their airway microbiota. CONCLUSIONS: Bacterial interactome disturbance characterized by reduced antagonistic interactions, rather than change in pathogen abundance or diversity, is a reproducible feature of airway dysbiosis in COPD clinical stability and exacerbations, which suggests that we may target interactome rather than pathogen alone for disease treatment.


Assuntos
Disbiose , Doença Pulmonar Obstrutiva Crônica , Humanos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Pulmão , Haemophilus , Escarro/microbiologia , Progressão da Doença
9.
J Orthop Surg Res ; 19(1): 249, 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38637795

RESUMO

PURPOSE: Preoperative anemia increases postoperative morbidity, mortality, and the risk of allogeneic transfusion. However, the incidence of preoperative anemia in patients undergoing total hip arthroplasty and total knee arthroplasty (TKA) and its relationship to postoperative outcomes has not been previously reported. METHODS: We conducted a comprehensive literature search through PubMed, Cochrane Library, Web of Sincien, and Embase from inception to July 2023 to investigate the prevalence of preoperative anemia in patients undergoing Total Joint Arthroplasty, comorbidities between anemic and non-anemicpatients before surgery, and postoperative outcomes. postoperative outcomes were analyzed. Overall prevalence was calculated using a random-effects model, and heterogeneity between studies was examined by Cochran's Q test and quantified by the I2 statistic. Subgroup analyses and meta-regression analyses were performed to identify sources of heterogeneity. Publication bias was assessed by funnel plots and validated by Egger's test. RESULTS: A total of 21 studies with 369,101 samples were included, all of which were retrospective cohort studies. 3 studies were of high quality and 18 studies were of moderate quality. The results showed that the prevalence of preoperative anemia was 22% in patients awaiting arthroplasty; subgroup analyses revealed that the prevalence of preoperative anemia was highest in patients awaiting revision of total knee arthroplasty; the highest prevalence of preoperative anemia was found in the Americas; preoperative anemia was more prevalent in the female than in the male population; and preoperative anemia with a history of preoperative anemia was more common in the female than in the male population. patients with a history of preoperative anemia; patients with joint replacement who had a history of preoperative anemia had an increased risk of infection, postoperative blood transfusion rate, postoperative blood transfusion, Deep vein thrombosis of the lower limbs, days in hospital, readmission within three months, and mortality compared with patients who did not have preoperative anemia. CONCLUSION: The prevalence of preoperative anemia in patients awaiting total joint arthroplasty is 22%, and is higher in TKA and female patients undergoing revision, while preoperative anemia is detrimental to the patient's postoperative recovery and will increase the risk of postoperative complications, transfusion rates, days in the hospital, readmission rates, and mortality.


Assuntos
Anemia , Artroplastia de Quadril , Artroplastia do Joelho , Humanos , Masculino , Feminino , Estudos Retrospectivos , Anemia/etiologia , Artroplastia do Joelho/efeitos adversos , Artroplastia de Quadril/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Extremidade Inferior
10.
Talanta ; 275: 126083, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38636442

RESUMO

MicroRNA (miRNA) is a promising biomarker that plays an important role in various biomedical applications, especially in cancer diagnosis. However, the current miRNA detection technology has inherent limitations such as complex operation, expensive testing cost and excessive detection time. In this study, a dual signal amplification biosensor based on DNA-functionalized metal-organic frameworks (MOFs) fluorescent probes, MFPBiosensor, was established for the enzyme-free and pretreatment-free detection of the colon cancer (CC) marker miR-23a. DNA-functionalized MOFs NH2-MIL-53(Al) (DNA@MOFs) were synthesized as fluorescent probes with specific recognition functions. A single DNA@MOF carries a large number of fluorescent ligands 2-aminoterephthalic acid (NH2-H2BDC), which can generate strong fluorescence signals after alkaline hydrolysis. Combined with catalyzed hairpin assembly (CHA), an efficient isothermal amplification technique, the dual signal enhancement strategy reduced matrix interference and sensitized the signal response. The established MFPBiosensor successfully detected extremely low levels of miRNA in complex biological samples with acceptable sensitivity and specificity. With a single detection cost of $0.583 and a test time of 50 min, the excellent inexpensive and rapid advantage of the MFPBiosensor is highlighted. More importantly, the subtle design enables the MFPBiosensor to achieve convenient batch detection, where miRNA in serum can be directly detected without any pretreatment process or enzyme. In conclusion, MFPBiosensor is a promising biosensor with substantial potential for commercial miRNA detection and clinical diagnostic applications of CC.

11.
Angew Chem Int Ed Engl ; : e202405379, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639181

RESUMO

Due to the superior catalytic activity and efficient utilization of noble metals, nanocatalysts are extensively used in the modern industrial production of chemicals. The surface structures of these materials are significantly influenced by reactive adsorbates, leading to dynamic behavior under experimental conditions. The dynamic nature poses significant challenges in studying the  structure-activity relations of catalysts. Herein, we unveil an anomalous entropic effect on catalysis via surface pre-melting of nanoclusters through machine learning accelerated molecular dynamics and free energy calculation. We find that due to the pre-melting of shell atoms, there exists a non-linear variation in the catalytic activity of the nanoclusters with temperature. Consequently, two notable changes in catalyst activity occur at the respective temperatures of melting for the shell and core atoms. We further study the nanoclusters with surface point defects, i.e. vacancy and ad-atom, and observe significant decrease in the surface melting temperatures of the nanoclusters, enabling the reaction to take place under more favorable and milder conditions. These findings not only provide novel insights into dynamic catalysis of nanoclusters  but also offer new understanding of the role of point defects in catalytic processes.

12.
Anim Reprod ; 21(1): e20230146, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562607

RESUMO

The subcortical maternal complex, which consists of maternal-effect genes, plays a crucial role in the development of oocytes and preimplantation embryo until the activation of the zygote genome. One such gene, known as peptidyl-arginine deiminase VI (Padi6), is involved in the oocyte maturation, fertilization and embryonic development. However, the precise function of Padi6 gene in buffalo is still unclear and requires further investigation. In this study, the sequence, mRNA and protein expression patterns of Padi6 gene were analyzed in oocytes, preimplantation embryos and somatic tissues of buffalo. The coding sequence of gene was successfully cloned and characterized. Real-time quantitative PCR results indicated an absence of Padi6 transcripts in somatic tissues. Notably, the expression levels of Padi6 in oocytes showed an increased from the germinal vesicle stage to metaphase II stage, followed by a rapid decrease during the morula and blastocyst stages. Immunofluorescence analysis confirmed these findings, revealing a noticeable decline in protein expression levels. Our research provides the initial comprehensive expression profile of Padi6 in buffalo oocytes and preimplantation embryos, serving as a solid foundation for further investigations into the functionality of maternal-effect genes in buffalo.

13.
Front Neurorobot ; 18: 1379906, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601918

RESUMO

Introduction: Periodicity, self-excitation, and time ratio asymmetry are the fundamental characteristics of the human gait. In order to imitate these mentioned characteristics, a pattern generator with four degrees of freedom is proposed based on cardioid oscillators developed by the authors. Method: The proposed pattern generator is composed of four coupled cardioid oscillators, which are self-excited and have asymmetric time ratios. These oscillators are connected with other oscillators through coupled factors. The dynamic behaviors of the proposed oscillators, such as phase locking, time ratio, and self-excitation, are analyzed via simulations by employing the harmonic balance method. Moreover, for comparison, the simulated trajectories are compared with the natural joint trajectories measured in experiments. Results and discussion: Simulation and experimental results show that the behaviors of the proposed pattern generator are similar to those of the natural lower limb. It means the simulated trajectories from the generator are self-excited without any additional inputs and have asymmetric time ratios. Their phases are locked with others. Moreover, the proposed pattern generator can be applied as the reference model for the lower limb exoskeleton controlling algorithm to produce self-adjusted reference trajectories.

14.
Nat Commun ; 15(1): 3100, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600159

RESUMO

In heterogeneous catalysis catalyst activation is often observed during the reaction process, which is mostly attributed to the induction by reactants. In this work we report that surface structure of molybdenum nitride (MoNx) catalyst exhibits a high dependency on the partial pressure or concentration of reaction products i.e., CO and H2O in reverse water gas-shift reaction (RWGS) (CO2:H2 = 1:3) but not reactants of CO2 and H2. Molybdenum oxide (MoOx) overlayers formed by oxidation with H2O are observed at reaction pressure below 10 mbar or with low partial pressure of CO/H2O products, while CO-induced surface carbonization happens at reaction pressure above 100 mbar and with high partial pressure of CO/H2O products. The reaction products induce restructuring of MoNx surface into more active molybdenum carbide (MoCx) to increase the reaction rate and make for higher partial pressure CO, which in turn promote further surface carbonization of MoNx. We refer to this as the positive feedback between catalytic activity and catalyst activation in RWGS, which should be widely present in heterogeneous catalysis.

15.
Nat Commun ; 15(1): 2969, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38582766

RESUMO

Artificial electronic kagome lattices may emerge from electronic potential landscapes using customized structures with exotic supersymmetries, benefiting from the confinement of Shockley surface-state electrons on coinage metals, which offers a flexible approach to realizing intriguing quantum phases of matter that are highly desired but scarce in available kagome materials. Here, we devise a general strategy to construct varieties of electronic kagome lattices by utilizing the on-surface synthesis of halogen hydrogen-bonded organic frameworks (XHOFs). As a proof of concept, we demonstrate three XHOFs on Ag(111) and Au(111) surfaces, which correspondingly deliver regular, breathing, and chiral breathing diatomic-kagome lattices with patterned potential landscapes, showing evident topological edge states at the interfaces. The combination of scanning tunnelling microscopy and noncontact atomic force microscopy, complemented by density functional theory and tight-binding calculations, directly substantiates our method as a reliable and effective way to achieve electronic kagome lattices for engineering quantum states.

16.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(2): 195-201, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38442938

RESUMO

The COVID-19 epidemic has spread to the whole world for three years and has had a serious impact on human life, health and economic activities. China's epidemic prevention and control has gone through the following stages: emergency unconventional stage, emergency normalization stage, and the transitional stage from the emergency normalization to the "Category B infectious disease treated as Category B" normalization, and achieved a major and decisive victory. The designated hospitals for prevention and control of COVID-19 epidemic in Tianjin has successfully completed its tasks in all stages of epidemic prevention and control, and has accumulated valuable experience. This article summarizes the experience of constructing a hospital infection prevention and control system during the "Category B infectious disease treated as Category A" period in designated hospital. The experience is summarized as the "Cluster" hospital infection prevention and control system, namely "three rings" outside, middle and inside, "three districts" of green, orange and red, "three things" before, during and after the event, "two-day pre-purification" and "two-director system", and "one zone" management. In emergency situations, we adopt a simplified version of the cluster hospital infection prevention and control system. In emergency situations, a simplified version of the "Cluster" hospital infection prevention and control system can be adopted. This system has the following characteristics: firstly, the system emphasizes the characteristics of "cluster" and the overall management of key measures to avoid any shortcomings. The second, it emphasizes the transformation of infection control concepts to maximize the safety of medical services through infection control. The third, it emphasizes the optimization of the process. The prevention and control measures should be comprehensive and focused, while also preventing excessive use. The measures emphasize the use of the least resources to achieve the best infection control effect. The fourth, it emphasizes the quality control work of infection control, pays attention to the importance of the process, and advocates the concept of "system slimming, process fattening". Fifthly, it emphasizes that the future development depends on artificial intelligence, in order to improve the quality and efficiency of prevention and control to the greatest extent. Sixth, hospitals need to strengthen continuous training and retraining. We utilize diverse training methods, including artificial intelligence, to ensure that infection control policies and procedures are simple. We have established an evaluation and feedback mechanism to ensure that medical personnel are in an emergency state at all times.


Assuntos
COVID-19 , Doenças Transmissíveis , Infecção Hospitalar , Humanos , Inteligência Artificial , COVID-19/prevenção & controle , Hospitais
17.
Heliyon ; 10(5): e27261, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38468927

RESUMO

To investigate the variation in the mechanical properties of clay under freeze-thaw cycles (FTCs), a series of experiments were conducted in the laboratory. Samples with different water contents and dry densities were subjected to FTCs ranging from 0 to 11 times. Then, cohesion, shear strength, internal friction angle and elastic modulus were obtained using triaxial test. The results show that with the increase in the number of FTCs, the shear strength, cohesion and elastic modulus decreased, while the internal friction angle increased slightly. However, the variation in the internal friction angle is not obvious, and the maximum increment is within 4°. The cohesion exhibited the most decrease after the first freeze-thaw action. Besides, under a same number of FTCs, four mechanical properties are significantly affected by water content and dry density. The shear strength, cohesion, elastic modulus and internal friction angle decrease with water content while increasing with dry density. Additionally, the elastic modulus is associated with confining pressure, which increases with confining pressure. This study provides evidence for the variation in mechanical properties of the soils subjected to FTCs and guides the design and construction of the cold regional engineering.

18.
J Colloid Interface Sci ; 665: 188-203, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38522159

RESUMO

Anti-tumor therapies reliant on reactive oxygen species (ROS) as primary therapeutic agents face challenges due to a limited oxygen substrate. Photodynamic therapy (PDT) is particularly hindered by inherent hypoxia, while chemodynamic therapy (CDT) encounters obstacles from insufficient endogenous hydrogen peroxide (H2O2) levels. In this study, we engineered biodegradable tumor microenvironment (TME)-activated hollow mesoporous MnO2-based nanotheranostic agents, designated as HAMnO2A. This construct entails loading artemisinin (ART) into the cavity and surface modification with a mussel-inspired polymer ligand, namely hyaluronic acid-linked poly(ethylene glycol)-diethylenetriamine-conjugated (3,4-dihydroxyphenyl) acetic acid, and the photosensitizer Chlorin e6 (mPEG-HA-Dien-(Dhpa/Ce6)), facilitating dual-modal imaging-guided PDT/CDT synergistic therapy. In vitro experimentation revealed that HAMnO2A exhibited ideal physiological stability and enhanced cellular uptake capability via CD44-mediated endocytosis. Additionally, it was demonstrated that accelerated endo-lysosomal escape through the pH-dependent protonation of Dien. Within the acidic and highly glutathione (GSH)-rich TME, the active component of HAMnO2A, MnO2, underwent decomposition, liberating oxygen and releasing both Mn2+ and ART. This process alleviates hypoxia within the tumor region and initiates a Fenton-like reaction through the combination of ART and Mn2+, thereby enhancing the effectiveness of PDT and CDT by generating increased singlet oxygen (1O2) and hydroxyl radicals (•OH). Moreover, the presence of Mn2+ ions enabled the activation of T1-weighted magnetic resonance imaging. In vivo findings further validated that HAMnO2A displayed meaningful tumor-targeting capabilities, prolonged circulation time in the bloodstream, and outstanding efficacy in restraining tumor growth while inducing minimal damage to normal tissues. Hence, this nanoplatform serves as an efficient all-in-one solution by facilitating the integration of multiple functions, ultimately enhancing the effectiveness of tumor theranostics.


Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Humanos , Fotoquimioterapia/métodos , Compostos de Manganês/farmacologia , Compostos de Manganês/química , Microambiente Tumoral , Nanomedicina Teranóstica/métodos , Peróxido de Hidrogênio/química , Óxidos/química , Fármacos Fotossensibilizantes/química , Neoplasias/tratamento farmacológico , Oxigênio , Hipóxia/tratamento farmacológico , Linhagem Celular Tumoral , Nanopartículas/química
19.
Int J Pharm ; 655: 124002, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38492898

RESUMO

Pterostilbene, a stilbene compound, demonstrates neuroprotective effects through its antioxidant and anti-inflammatory properties. However, pterostilbene exhibits low bioavailability. We developed a pterostilbene nanoemulsion with better release stability and particle size. Behavioral tests, including the Y maze, new object recognition, and water maze, revealed that the pterostilbene nanoemulsion demonstrated a more significant effect on improving learning and memory function than pterostilbene. Immunofluorescence analysis revealed that pterostilbene nanoemulsion was more potent in safeguarding hippocampal neurons and inhibiting apoptosis and oxidative stress than pterostilbene. Further results from the Western blot and quantitative reverse transcription polymerase chain reaction indicated that the enhanced efficacy of pterostilbene nanoemulsion may be attributed to its stronger promotion of the nuclear factor erythroid 2-related factor 2 signaling pathway. Hence, enhanced drug delivery efficiency decreased dosage requirements and increased the bioavailability of pterostilbene, thereby potentially providing a safe, effective, and convenient treatment option for patients with Alzheimer's disease.


Assuntos
Doença de Alzheimer , Estilbenos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Transdução de Sinais , Estilbenos/farmacologia , Estilbenos/uso terapêutico , Animais , Camundongos
20.
Food Chem ; 448: 139119, 2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38547703

RESUMO

Buffalo colostrum is the initial mammary secretion after parturition, consisting of nutritional and bioactive components. In this study, we conducted a proteomic analysis of buffalo colostrum whey to identify bioactive proteins and peptides. A total of 107 differentially expressed proteins (DEPs) were identified in buffalo colostrum whey compared to those in mature milk. Gene Ontology analysis revealed that DEPs were primarily associated with immune response and tissue development. KEGG pathway enrichment suggested that colostrum actively enhances nascent immunity involved in interleukin and interferon signaling pathways. Furthermore, candidate antimicrobial peptides (AMPs) of whey protein hydrolysates from buffalo colostrum were characterized, which exhibits broad-spectrum activity against gram-positive and gram-negative pathogens. Overall, this study improves our understanding of protein variations in buffalo lactation, and contributes to the development of AMPs from buffalo colostrum.

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