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1.
Front Nutr ; 11: 1304519, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38577157

RESUMO

Introduction: Produce prescription programs are rapidly expanding as a type of Food is Medicine intervention with prospects for mitigating food insecurity and reducing diet-related health disparities. Gaining insight into participant perspectives on program logistics and perceived impacts is crucial to program success and improvements. Methods: Between May and June 2021, we conducted individual and small group interviews with 23 caregivers with children aged 1-5 years who participated in a produce prescription program from 2020 to 2021 in Texas, U.S. They were provided with a gift card to a major national grocery retailer to purchase fresh produce. The card was reloaded $60 monthly for 8 months with automatic roll-over of unused funds to the next month. Participants also received nutrition education in the form of two videos. A deductive analysis approach was employed, and NVivo qualitative data analysis software was used to perform coding and to assist with subsequent analyses. Results: All 23 participants were female, with an average age of 37.5 years, and the majority identified as Hispanic/Latino (83%). About 43% of the families had three or more children. Six themes were generated from interviews. Three of these themes were related to program logistics: (1) ease of program use; (2) participant satisfaction with the incentive; and (3) desire for additional store options. The remaining main themes pertained to program impact: (1) the enhanced ability to purchase produce; (2) the usefulness of the nutrition education; and (3) persistent challenges encountered when preparing the produce for picky eaters and young children. Conclusion: A pediatric produce prescription program was perceived as logistically easy and a helpful source of financial support for accessing fresh produce. Program features such as card-based incentive system and partnership with major grocery retailer were favored by participants. For future program design, it may be beneficial to consider collaborating with multiple grocery outlets and enhancing the intensity and targeting of nutrition education.

2.
Pharmacol Res ; 203: 107175, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38582357

RESUMO

Cisplatin, a frequently prescribed chemotherapeutic agent, serves as a clinically therapeutic strategy for a broad range of malignancies. Its primary mode of action centers around interference with DNA replication and RNA transcription, thereby inducing apoptosis in cancer cells. Nevertheless, the clinical utility of cisplatin is constrained by its severe adverse effects and the burgeoning problem of drug resistance. Ginsenosides, potent bioactive constituents derived from ginseng, possess an array of biological activities. Recent scientific investigations underscore the substantial amplification of cisplatin's anticancer potency and the mitigation of its harmful side effects when administered concomitantly with ginsenosides. This review aims to explore the underlying mechanisms at play in this combination therapy. Initially, we provide a concise introduction to the cisplatin. Then, we pivot towards illuminating how ginsenosides bolster the anticancer efficacy of cisplatin and counteract cisplatin resistance, culminating in enhanced therapeutic outcomes. Furthermore, we provide an extensive discussion on the reduction of cisplatin-induced toxicity in the kidneys, liver, gastrointestinal tract, nervous system, and ear, accompanied by immune-fortification with ginsenosides. The existing clinical combined use of cisplatin and ginsenosides is also discussed. We propose several recommendations to propel additional research into the mechanisms governing the synergistic use of ginsenosides and cisplatin, thereby furnishing invaluable insights and fostering advancement in combined modality therapy.

3.
Cell Death Discov ; 10(1): 170, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38594265

RESUMO

Exosomes are a subtype of extracellular vesicles composed of bioactive molecules, including nucleic acids, proteins, and lipids. Exosomes are generated by the fusion of intracellular multivesicular bodies (MVBs) with the cell membrane and subsequently released into the extracellular space to participate in intercellular communication and diverse biological processes within target cells. As a crucial mediator, exosomes have been implicated in regulating ferroptosis-an iron-dependent programmed cell death characterized by lipid peroxide accumulation induced by reactive oxygen species. The involvement of exosomes in iron, lipid, and amino acid metabolism contributes to their regulatory role in specific mechanisms underlying how exosomes modulate ferroptosis, which remains incompletely understood, and some related studies are still preliminary. Therefore, targeting the regulation of ferroptosis by exosomes holds promise for future clinical treatment strategies across various diseases. This review aims to provide insights into the pathophysiology and mechanisms governing the interaction between exosomes and ferroptosis and their implications in disease development and treatment to serve as a reference for further research.

4.
J Nutr ; 154(4): 1321-1332, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38582699

RESUMO

BACKGROUND: Obesity is a progressive metabolic disease that begins with lipid metabolism disorders. Aromatic amino acids (AAAs), including tryptophan, phenylalanine, and tyrosine, have diverse biological activities as nutrients. However, the underlying mechanisms by which AAAs affect lipid metabolism are unclear. OBJECTIVES: This study was designed to investigate the possible roles and underlying molecular mechanisms of AAA in the pathogenesis of lipid metabolism disorders. METHODS: We added an AAA mixture to the high-fat diet (HFD) of mice. Glucose tolerance test was recorded. Protein expression of hepatic bile acid (BA) synthase and mRNA expression of BA metabolism-related genes were determined. Hepatic BA profiles and gut microbial were also determined in mice. RESULTS: The results showed that AAA significantly increased body weight and white adipose tissue, aggravated liver injury, impaired glucose tolerance and intestinal integrity, and significantly increased hepatic BA synthesis by inhibiting intestinal farnesoid X receptor (FXR). Moreover, AAA increased the content of total BA in the liver and altered the hepatic BA profile, with elevated levels of lithocholic acid, glycochenodeoxycholic acid, and glycoursodeoxycholic acid. AAA markedly increased the levels of proteins involved in BA synthesis (cholesterol 7α-hydroxylase and oxysterol 7α-hydroxylase) and inhibited the intestinal FXR. Gut microbial composition also changed, reducing the abundance of some beneficial bacteria, such as Parvibacter and Lactobacillus. CONCLUSIONS: Under HFD conditions, AAAs stimulate BA synthesis in both the classical and alternative pathways, leading to aggravation of liver injury and fat deposition. Excessive intake of AAA disrupts BA metabolism and contributes to the development of lipid metabolism disorders, suggesting that AAA may be a causative agent of lipid metabolism disorders.


Assuntos
Transtornos do Metabolismo dos Lipídeos , Metabolismo dos Lipídeos , Camundongos , Animais , Aminoácidos Aromáticos , Fígado/metabolismo , Transtornos do Metabolismo dos Lipídeos/metabolismo , Ácidos e Sais Biliares/metabolismo , Camundongos Endogâmicos C57BL
5.
J Nutr ; 154(4): 1333-1346, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38582698

RESUMO

BACKGROUND: The increase in circulating insulin levels is associated with the onset of type 2 diabetes (T2D), and the levels of branched-chain amino acids and aromatic amino acids (AAAs) are altered in T2D, but whether AAAs play a role in insulin secretion and signaling remains unclear. OBJECTIVES: This study aimed to investigate the effects of different AAAs on pancreatic function and on the use of insulin in finishing pigs. METHODS: A total of 18 healthy finishing pigs (Large White) with average body weight of 100 ± 1.15 kg were randomly allocated to 3 dietary treatments: Con, a normal diet supplemented with 0.68% alanine; Phe, a normal diet supplemented with 1.26% phenylalanine; and Trp, a normal diet supplemented with 0.78% tryptophan. The 3 diets were isonitrogenous. There were 6 replicates in each group. RESULTS: Herein, we investigated the effects of tryptophan and phenylalanine on pancreatic function and the use of insulin in finishing pigs and found that the addition of tryptophan and phenylalanine aggravated pancreatic fat deposition, increased the relative content of saturated fatty acids, especially palmitate (C16:0) and stearate (C18:0), and the resulting lipid toxicity disrupted pancreatic secretory function. We also found that tryptophan and phenylalanine inhibited the growth and secretion of ß-cells, downregulated the gene expression of the PI3K/Akt pathway in the pancreas and liver, and reduced glucose utilization in the liver. CONCLUSIONS: Using fattening pigs as a model, multiorgan combined analysis of the insulin-secreting organ pancreas and the main insulin-acting organ liver, excessive intake of tryptophan and phenylalanine will aggravate pancreatic damage leading to glucose metabolism disorders, providing new evidence for the occurrence and development of T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Triptofano , Suínos , Animais , Fenilalanina , Fosfatidilinositol 3-Quinases , Dieta , Insulina , Ração Animal/análise
6.
J Anim Sci Biotechnol ; 15(1): 56, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584279

RESUMO

BACKGROUND: Cold stress has negative effects on the growth and health of mammals, and has become a factor restricting livestock development at high latitudes and on plateaus. The gut-liver axis is central to energy metabolism, and the mechanisms by which it regulates host energy metabolism at cold temperatures have rarely been illustrated. In this study, we evaluated the status of glycolipid metabolism and oxidative stress in pigs based on the gut-liver axis and propose that AMP-activated protein kinase (AMPK) is a key target for alleviating energy stress at cold temperatures by dietary fat supplementation. RESULTS: Dietary fat supplementation alleviated the negative effects of cold temperatures on growth performance and digestive enzymes, while hormonal homeostasis was also restored. Moreover, cold temperature exposure increased glucose transport in the jejunum. In contrast, we observed abnormalities in lipid metabolism, which was characterized by the accumulation of bile acids in the ileum and plasma. In addition, the results of the ileal metabolomic analysis were consistent with the energy metabolism measurements in the jejunum, and dietary fat supplementation increased the activity of the mitochondrial respiratory chain and lipid metabolism. As the central nexus of energy metabolism, the state of glycolipid metabolism and oxidative stress in the liver are inconsistent with that in the small intestine. Specifically, we found that cold temperature exposure increased glucose transport in the liver, which fully validates the idea that hormones can act on the liver to regulate glucose output. Additionally, dietary fat supplementation inhibited glucose transport and glycolysis, but increased gluconeogenesis, bile acid cycling, and lipid metabolism. Sustained activation of AMPK, which an energy receptor and regulator, leads to oxidative stress and apoptosis in the liver; dietary fat supplementation alleviates energy stress by reducing AMPK phosphorylation. CONCLUSIONS: Cold stress reduced the growth performance and aggravated glycolipid metabolism disorders and oxidative stress damage in pigs. Dietary fat supplementation improved growth performance and alleviated cold temperature-induced energy stress through AMPK-mediated mitochondrial homeostasis. In this study, we highlight the importance of AMPK in dietary fat supplementation-mediated alleviation of host energy stress in response to environmental changes.

7.
Inorg Chem ; 63(14): 6418-6426, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38526055

RESUMO

Direct photocatalytic hydrogen from earth-abundant seawater is a great potential way to achieve sustainable and clean energy, yet unsatisfactory decomposition and rapid electron-hole pair recombination of catalysts hinder the solar-driven H2 conversion efficiency. Herein, we designed a series of PtCu alloy nanoparticle-modified porous triptycene-based polymers (PtxCu1-TCP) to construct the heterostructure for highly efficient hydrogen generation from photocatalytic water/seawater splitting. Characterizations displayed that TCP with an ultrahigh surface area can confine the agglomeration of PtCu alloy; meanwhile, the PtCu alloy can facilitate the rapid electron transfer from TCP. In addition, TCP with a stable covalent bond structure can resist the corrosion of seawater. Benefiting from these two advantages, Pt7Cu1-TCP showed a remarkably enhanced photocatalytic performance with a maximum H2 evolution rate of 3255 µmol g-1 h-1 in natural seawater with triethanolamine, which is 2.69, 116.25, and 1.08 times that of Pt-TCP, Cu-TCP, and optimal catalyst in pure water, respectively. This study provides an idea for the development of a novel catalytic system for hydrogen production from solar-driven water/seawater splitting.

8.
Water Res ; 254: 121399, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38447375

RESUMO

Despite numerous studies investigating the occurrence and fate of microplastics, no effort has been devoted toward exploring the characteristics of dissolved organic matter (DOM) leached from face masks mainly made of plastics and additives used in large quantities during the COVID-19 pandemic. By using FTIR, UV-vis, fluorescence EEM coupling with FRI and PARAFAC, and kinetic models of leaching experiments, we explored the leaching behaviors of face mask-derived DOM (FM-DOM) from commonly used face masks including N95, KN95, medical surgical masks, etc. The concentration of FM-DOM increased quickly at early 0-48 h and reached equilibrium at about 48 h measured in terms of dissolved organic carbon and fluorescence intensity. The protein-like materials ranged from 80.32 % to 89.40 % of percentage fluorescence response (Pi,n) were dominant in four types of FM-DOM analyzed by fluorescence EEM-FRI during the leaching experiments from 1 to 360 h. Four fluorescent components were identified, which included tryptophan-like components, tyrosine-like components, microbial protein-like components, and fulvic-like components with fluorescence EEM-PARAFAC models. The multi-order kinetic model (Radj2 0.975-0.999) fitted better than the zero-order and first-order kinetic model (Radj2 0.936-0.982) for all PARAFAC components of FM-DOM based on equations derived by pseudo kinetic models. The leaching rate constants (kn) ranged from 0.058 to 30.938 and the half-life times (T1/2) ranged from 2.73 to 24.87 h for four FM-DOM samples, following the solubility order of fulvic-like components (C4) > microbial protein-like components (C3) > tryptophan-like components (C1) > tyrosine-like components (C2) for FM-DOM from four types of face masks during the leaching experiment from 0 to 360 h. These novel findings will contribute to the understanding of the underappreciated environment impact of face masks in aquatic ecosystems.


Assuntos
Matéria Orgânica Dissolvida , Plásticos , Humanos , Ecossistema , Máscaras , Pandemias , Triptofano , Espectrometria de Fluorescência , Tirosina , Substâncias Húmicas/análise , Análise Fatorial
9.
ACS Nano ; 18(12): 8600-8625, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38469753

RESUMO

Accurately controlling magnetic and spin states presents a significant challenge in spintronics, especially as demands for higher data storage density and increased processing speeds grow. Approaches such as light control are gradually supplanting traditional magnetic field methods. Traditionally, the modulation of magnetism was predominantly achieved through polarized light with the help of ultrafast light technologies. With the growing demand for energy efficiency and multifunctionality in spintronic devices, integrating photovoltaic materials into magnetoelectric systems has introduced more physical effects. This development suggests that sunlight will play an increasingly pivotal role in manipulating spin orientation in the future. This review introduces and concludes the influence of various light types on magnetism, exploring mechanisms such as magneto-optical (MO) effects, light-induced magnetic phase transitions, and spin photovoltaic effects. This review briefly summarizes recent advancements in the light control of magnetism, especially sunlight, and their potential applications, providing an optimistic perspective on future research directions in this area.

10.
Front Psychol ; 15: 1338796, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529089

RESUMO

The relationship between anxiety and sleep disorders is a key research topic in the academic community. However, evidence on the mechanism through which anxiety influences sleep disorders remains limited. The purpose of this study was to investigate the roles of flourishing and neuroticism in the mechanism through which anxiety influences sleep disorders in medical students. We constructed a moderated mediation model and tested the mediating role of flourishing and the moderating role of neuroticism in medical college students. The results showed that: (1) anxiety was significantly and positively related to sleep disorders and significantly and negatively related to flourishing; flourishing was significantly and negatively related to sleep disorders; neuroticism was significantly and positively related to sleep disorders; (2) flourishing had a mediation effect on the relationship between anxiety and sleep disorders; (3) neuroticism moderated the process through which flourishing mediated the effect of anxiety on sleep disorders. Our research expands the literature on the mechanism underlying the effects of anxiety on sleep disorders and provides insights into the potential prevention and intervention of sleep and emotional problems in medical students.

11.
Inorg Chem ; 63(9): 4429-4437, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38377564

RESUMO

Designing and fabricating efficient and stable nonprecious metal-based oxygen reduction reaction (ORR) electrocatalysts is a pressing and challenging task for the pursuit of sustainable new energy devices. Herein, porous P-CoSe2@NC electrocatalysts with high-density carbon-coated CoSe2 sites were successfully fabricated based on a pyridyl-porphyrinic metal-organic framework (Co-TPyP MOF) via a molten salt-assisted synthesis method. The hierarchical pore and N-doping carbon substrate of P-CoSe2@NC promotes mass transfer and electron-transfer efficiency, which is beneficial to maximize CoSe2 site utilization. Well-designed P-CoSe2@NC exhibits efficient ORR catalytic activity with a high half-wave potential of 0.863 V and excellent catalytic stability. Meanwhile, rechargeable aqueous primary/quasi-solid-state ZABs based on a P-CoSe2@NC air cathode show a high peak power density and exceptional operating stability, catering to the demands of practical applications. The qualified performance and structure stability of the electrocatalytic system may be mainly attributed to the protection of the CoSe2 nanoparticle by the coated carbon layer. Given the rational design of the structure and the component of the electrocatalyst with enhanced ORR activity, we believe that this work has provided a reliable pathway to the development of high-performance transition-metal chalcogenides for energy-storage and -conversion devices.

12.
Front Immunol ; 15: 1289644, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333214

RESUMO

Chlamydia trachomatis, is a kind of obligate intracellular pathogen. The removal of C. trachomatis relies primarily on specific cellular immunity. It is currently considered that CD4+ Th1 cytokine responses are the major protective immunity against C. trachomatis infection and reinfection rather than CD8+ T cells. The non-specific immunity (innate immunity) also plays an important role in the infection process. To survive inside the cells, the first process that C. trachomatis faces is the innate immune response. As the "sentry" of the body, mast cells attempt to engulf and remove C. trachomatis. Dendritic cells present antigen of C. trachomatis to the "commanders" (T cells) through MHC-I and MHC-II. IFN-γ produced by activated T cells and natural killer cells (NK) further activates macrophages. They form the body's "combat troops" and produce immunity against C. trachomatis in the tissues and blood. In addition, the role of eosinophils, basophils, innate lymphoid cells (ILCs), natural killer T (NKT) cells, γδT cells and B-1 cells should not be underestimated in the infection of C. trachomatis. The protective role of innate immunity is insufficient, and sexually transmitted diseases (STDs) caused by C. trachomatis infections tend to be insidious and recalcitrant. As a consequence, C. trachomatis has developed a unique evasion mechanism that triggers inflammatory immunopathology and acts as a bridge to protective to pathological adaptive immunity. This review focuses on the recent advances in how C. trachomatis evades various innate immune cells, which contributes to vaccine development and our understanding of the pathophysiologic consequences of C. trachomatis infection.


Assuntos
Infecções por Chlamydia , Chlamydia trachomatis , Humanos , Linfócitos T CD8-Positivos , Imunidade Inata , Interferon gama , Linfócitos/patologia
13.
Environ Res ; 249: 118358, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38325777

RESUMO

Increasing the electron-hole recombination rate in g-C3N4 can effectively improve its photocatalytic performance. In this work, NiCoP/g-C3N4 (NCP/PCN) composites with ohmic junction were formed by embedding granular NiCoP in irregularly porous g-C3N4. There was almost no barrier between the metal and the semiconductor in ohmic junction, which made it easier for electrons to slip from PCN to NCP along the curved energy band, and NCP acted as an electron collector to rapidly capture the slipping electrons. In addition, porous g-C3N4 prepared by supramolecular self-assembly could provide a shorter diffusion path for electrons. Thus, the electron-hole was effectively separated and the photocatalytic performance was improved. The band electronic structure and existence of ohmic junction in 7-NCP/PCN composite were demonstrated by XPS, ESR and DFT calculation. Finally, a reasonable photocatalytic degradation mechanism and possible tetracycline degradation path were proposed. This work has significant potential for providing an effective method for the design of non-precious metal photocatalysts.

14.
Polymers (Basel) ; 16(4)2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38399834

RESUMO

To evaluate the thermal stability of composite polymer-modified asphalt, thermoplastic elastomer styrene-butadiene rubber (SBR)/polypropylene (PP) pellets were prepared using a hot-melt blending technique, with butyl rubber powder and waste polypropylene pellets as raw materials. The effects of different evaluation indexes on the thermal stability of SBR/PP-modified asphalt were investigated using a frequency scan test and a multi-stress creep recovery (MSCR) test, and the compatibility of SBR/PP particles with asphalt was studied using the Cole-Cole diagram and microstructure images. The tests show that, firstly, the performance grade (PG) classification of asphalt can be improved by adding an SBR/PP thermoplastic elastomer to enhance the adaptability of asphalt in high- and low-temperature environments, and the evaluation separation index can reflect the high-temperature storage stability of composite-modified asphalt more reasonably. Additionally, the larger the rubber-to-plastic ratio the worse the high-temperature thermal stability of composite-modified asphalt. Moreover, the addition of additives to the composite particles can promote the SBR/PP particles in the asphalt to be more uniformly dispersed, forming a more desirable microstructure and improving the thermal stability of composite-modified asphalt. Ultimately, the semicircular curve of the Cole-Cole diagram can reflect the compatibility characteristics of the two-phase structure of SBR/PP-modified asphalt, which can be used as an auxiliary index to evaluate the compatibility of polymer-modified asphalt.

15.
Front Nutr ; 11: 1300860, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38371505

RESUMO

Background: The association between natural products and dietary interventions on liver enzymes is unclear; therefore, this study aimed to examine their effects on liver enzymes in adults. Methods: PubMed, Embase, and Cochrane Library of Systematic Reviews databases were searched from inception until March 2023. The Assessment of Multiple Systematic Reviews-2 (AMSTAR-2) and Grading of Recommendations Assessment, Development, and Evaluation (GRADE) systems were used to assess the methodological and evidence quality, and the therapeutic effects were summarized in a narrative form. Results: A total of 40 meta-analyses on natural products (n = 25), dietary supplements (n = 10), and dietary patterns (n = 5) were evaluated, and results were presented in a narrative form. The overall methodological quality of the included studies was relatively poor. The results indicated that positive effects were observed for nigella sativa, garlic, artichoke, curcumin, silymarin, vitamin E, vitamin D, L-carnitine, propolis, and polyunsaturated fatty acids on certain liver enzymes. The dietary patterns, including high-protein, Mediterranean, and calorie-restriction diets and evening snacks, may reduce liver enzymes; however, other supplements and herbs did not reduce liver enzyme levels or have minimal effects. The evidence quality was generally weak given the risk of bias, heterogeneity, and imprecision. Conclusion: This umbrella review suggests that natural products and dietary interventions have beneficial therapeutic effects on liver enzymes levels. Further clinical trials are necessary to establish the effectiveness of supplements that reduce liver enzymes.

16.
J Org Chem ; 89(3): 1736-1747, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38215479

RESUMO

An effective method was explored for the selective synthesis of sulfonamides and sulfenamides using sodium sulfinates and amines as starting materials. This method offers mild reaction conditions, a broad substrate scope, high efficiency, and readily accessible materials, making it suitable and an alternative strategy for the preparation of a variety of biologically or pharmaceutically active compounds.

17.
IEEE Trans Med Imaging ; PP2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38163305

RESUMO

Deep learning techniques have been investigated for the computer-aided diagnosis of thyroid nodules in ultrasound images. However, most existing thyroid nodule detection methods were simply based on static ultrasound images, which cannot well explore spatial and temporal information following the clinical examination process. In this paper, we propose a novel video-based semi-supervised framework for ultrasound thyroid nodule detection. Especially, considering clinical examinations that need to detect thyroid nodules at the ultrasonic probe positions, we first construct an adjacent frame guided detection backbone network by using adjacent supporting reference frames. To further reduce the labour-intensive thyroid nodule annotation in ultrasound videos, we extend the video-based detection in a semi-supervised manner by using both labeled and unlabeled videos. Based on the detection consistency in sequential neighbouring frames, a pseudo label adaptation strategy is proposed for the refinement of unpredicted frames. The proposed framework is validated on 996 transverse viewed and 1088 longitudinal viewed ultrasound videos. Experimental results demonstrated the superior performance of our proposed method in the ultrasound video-based detection of thyroid nodules.

18.
J Mol Model ; 30(1): 19, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38165505

RESUMO

CONTEXT: Polyimide (PI) and aramid, as functional polymer materials, have significant application prospects in special fields such as fire prevention and arc resistance. Blends of materials can not only improve the physical and chemical properties of a single material, but also save costs, so in order to improve the performance of polyimide, it is of great practical importance to study the properties of PI and aramid blends. Molecular dynamics simulation results showed that the two materials are compatible. The solubility parameters of PI tend to stabilize when the polymerization degree exceeded 10; aramid-1313 and aramid-1414 tend to stabilize at polymerization degrees of 10 and 15 or more, respectively. On this basis, the binding energy, diffusion coefficient, and mechanical properties of PI/aramid-1313 and PI/aramid-1414 blends with different mass ratios were analyzed. It was found that with the continuous increase of aramid content, the binding energy of the blends continue to improve, limiting the gas molecules diffusion ability. The mechanical properties of the materials also continue to improve. The simulation results provided in this paper can provide theoretical guidance for experiments on PI blends and shorten the research time and cost. METHODS: To investigate the properties of PI and aramid blends, the PI/aramid composite system models were constructed using the Amorphous Cell module in Materials Studio software. Subsequently, molecular dynamics simulations of the PI/aramid composite system were performed using the Forcite module, while the interactions between atoms and molecules were described using the COMPASS II force field.

19.
J Anim Sci ; 1022024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38266070

RESUMO

Nisin (Ni) is a polypeptide bacteriocin produced by lactic streptococci (probiotics) that can inhibit the majority of gram-positive bacteria, and improve the growth performance of broilers, and exert antioxidative and anti-inflammatory properties. The present study investigated the potential preventive effect of Nisin on necrotic enteritis induced by Clostridium perfringens (Cp) challenge. A total of 288 Arbor Acres broiler chickens of 1-d-olds were allocated using 2 × 2 factorial arrangement into four groups with six replicates (12 chickens per replicate), including: (1) control group (Con, basal diet), (2) Cp challenge group (Cp, basal diet + 1.0 × 108 CFU/mL Cp), (3) Ni group (Ni, basal diet + 100 mg/kg Ni), and (4) Ni + Cp group (Ni + Cp, basal diet + 100 mg/kg Ni + 1.0 × 108 CFU/mL Cp). The results showed that Cp challenge decreased the average daily gain (ADG) of days 15 to 21 (P<0.05) and increased interleukin-6 (IL-6) content in the serum (P < 0.05), as well as a significant reduction in villus height (VH) and the ratio of VH to crypt depth (VCR) (P<0.05) and a significant increase in crypt depth (CD) of jejunum (P<0.05). Furthermore, the mRNA expressions of Occludin and Claudin-1 were downregulated (P<0.05), while the mRNA expressions of Caspase3, Caspase9, Bax, and Bax/Bcl-2 were upregulated (P<0.05) in the jejunum. However, the inclusion of dietary Ni supplementation significantly improved body weight (BW) on days 21 and 28, ADG of days 15 to 21 (P<0.05), decreased CD in the jejunum, and reduced tumor necrosis factor-α (TNF-α) content in the serum (P<0.05). Ni addition upregulated the mRNA levels of Claudin-1 expression and downregulated the mRNA expression levels of Caspase9 in the jejunum (P<0.05). Moreover, Cp challenge and Ni altered the cecal microbiota composition, which manifested that Cp challenge decreased the relative abundance of phylum Fusobacteriota and increased Shannon index (P<0.05) and the trend of phylum Proteobacteria (0.05

Necrotic enteritis (NE), a severe digestive disorder in broiler chickens caused by Clostridium perfringens (Cp), a gram-positive bacterium, is a widespread issue in the global poultry industry, leading to significant economic losses. Nisin (Ni), a polypeptide bacteriocin produced by probiotic lactic streptococci, has been found to enhance daily weight gain and feed intake, while also exhibiting inhibitory effects on gram-positive bacteria and anti-inflammatory properties. In this study, a NE infection model in broilers was established to examine the potential preventive effects of Ni. These results demonstrated that Cp challenge reduced growth performance, caused inflammatory responses and intestinal apoptosis, damaged intestinal morphology and barrier function, and was accompanied by changes in the composition of the gut microbiota. Dietary supplementation with Ni improved growth performance and protected intestine against Cp challenge-induced damage in broilers. As a result, Ni may be a potential safe and effective additive for NE prevention in broiler production.


Assuntos
Infecções por Clostridium , Nisina , Doenças das Aves Domésticas , Animais , Clostridium perfringens , Galinhas , Intestinos , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , Infecções por Clostridium/microbiologia , Nisina/farmacologia , Claudina-1 , Proteína X Associada a bcl-2/farmacologia , Dieta/veterinária , RNA Mensageiro/genética , Imunidade , Doenças das Aves Domésticas/microbiologia , Suplementos Nutricionais , Ração Animal/análise
20.
Angew Chem Int Ed Engl ; 63(10): e202318159, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38189634

RESUMO

Molecular emitters with multi-emissive properties are in high demand in numerous fields, while these properties basically depend on specific molecular conformation and packing. For amorphous systems, special molecular arrangement is unnecessary, but it remains challenging to achieve such luminescent behaviors. Herein, we present a general strategy that takes advantage of molecular rigidity and S1 -T1 energy gap balance for emitter design, which enables fluorescence-phosphorescence dual-emission properties in various solid forms, whether crystalline or amorphous. Subsequently, the amorphism of the emitters based polymethyl methacrylate films endowed an in situ regulation of the dual-emissive characteristics. With the ratiometric regulation of phosphorescence by external stimuli and stable fluorescence as internal reference, highly controllable luminescent color tuning (yellow to blue including white emission) was achieved. There properties together with a persistent luminous behavior is of benefit for an irreplaceable set of optical information combination, featuring an ultrahigh-security anti-counterfeiting ability. Our research introduces a concept of eliminating the crystal-form and molecular-conformational dependence of complex luminescent properties through emitter molecular design. This has profound implications for the development of functional materials.

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