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1.
Biochem Biophys Res Commun ; 711: 149911, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38603832

RESUMO

Macrophages play a crucial role in host response and wound healing, with M2 polarization contributing to the reduction of foreign-body reactions induced by the implantation of biomaterials and promoting tissue regeneration. Electrical stimulation (ES) and micropatterned substrates have a significant impact on the macrophage polarization. However, there is currently a lack of well-established cell culture platforms for studying the synergistic effects of these two factors. In this study, we prepared a graphene free-standing substrate with 20 µm microgrooves using capillary forces induced by water evaporation. Subsequently, we established an ES cell culture platform for macrophage cultivation by integrating a self-designed multi-well chamber cell culture device. We observed that graphene microgrooves, in combination with ES, significantly reduce cell spreading area and circularity. Results from immunofluorescence, ELISA, and flow cytometry demonstrate that the synergistic effect of graphene microgrooves and ES effectively promotes macrophage M2 phenotypic polarization. Finally, RNA sequencing results reveal that the synergistic effects of ES and graphene microgrooves inhibit the macrophage actin polymerization and the downstream PI3K signaling pathway, thereby influencing the phenotypic transition. Our results demonstrate the potential of graphene-based microgrooves and ES to synergistically modulate macrophage polarization, offering promising applications in regenerative medicine.


Assuntos
Estimulação Elétrica , Grafite , Macrófagos , Grafite/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Animais , Camundongos , Células RAW 264.7 , Polaridade Celular/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais
2.
Chemistry ; 30(43): e202401303, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38794842

RESUMO

Developing pragmatic strategies for accessing functional benzofuran-2-ones from 3-([1,1'-biphenyl]-2-yl)benzofuran remains an enduring challenge. Herein, we have achieved a highly discriminating electrochemical oxidative dearomative spiroannulation of 3-([1,1'-biphenyl]-2-yl)benzofuran, culminating in the synthesis of 2H-spiro[benzofuran-3,9'-fluoren]-2-one derivatives. By harnessing the electrophilic intermediates of benzofuryl radical cations supported by DFT calculations, we attain exceptional regioselectivity while eliminating the need for stoichiometric oxidants. Mechanistic investigations reveal a sequence of events involving the benzofuran radical cation, encompassing the capture of H2O, nucleophilic arene attack, and subsequent deprotonation, ultimately yielding the final benzofuran-2-ones.

3.
Cell Commun Signal ; 22(1): 357, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987851

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is highly prevalent worldwide, and its global burden is substantial and growing. CKD displays a number of features of accelerated senescence. Tubular cell senescence is a common biological process that contributes to CKD progression. Tubulointerstitial inflammation is a driver of tubular cell senescence and a common characteristic of CKD. However, the mechanism by which the interstitial inflammation drives tubular cell senescence remains unclear. This paper aims to explore the role of exosomal miRNAs derived from macrophages in the development of tubular cell senescence. METHODS: Among the identified inflammation-related miRNAs, miR-155 is considered to be one of the most important miRNAs involved in the inflammatory response. Macrophages, the primary immune cells that mediate inflammatory processes, contain a high abundance of miR-155 in their released exosomes. We assessed the potential role of miR-155 in tubular cell senescence and renal fibrosis. We subjected miR-155-/- mice and wild-type controls, as well as tubular epithelial cells (TECs), to angiotensin II (AngII)-induced kidney injury. We assessed kidney function and injury using standard techniques. TECs were evaluated for cell senescence and telomere dysfunction in vivo and in vitro. Telomeres were measured by the fluorescence in situ hybridization. RESULTS: Compared with normal controls, miR-155 was up-regulated in proximal renal tubule cells in CKD patients and mouse models of CKD. Moreover, the expression of miR-155 was positively correlated with the extent of renal fibrosis, eGFR decline and p16INK4A expression. The overexpression of miR-155 exacerbated tubular senescence, evidenced by increased detection of p16INK4A/p21expression and senescence-associated ß-galactosidase activity. Notably, miR-155 knockout attenuates renal fibrosis and tubule cell senescence in vivo. Interestingly, once released, macrophages-derived exosomal miR-155 was internalized by TECs, leading to telomere shortening and dysfunction through targeting TRF1. A dual-luciferase reporter assay confirmed that TRF1 was the direct target of miR-155. Thus, our study clearly demonstrates that exosomal miR-155 may mediate communication between macrophages and TECs, subsequently inducing telomere dysfunction and senescence in TECs. CONCLUSIONS: Our work suggests a new mechanism by which macrophage exosomes are involved in the development of tubule senescence and renal fibrosis, in part by delivering miR-155 to target TRF1 to promote telomere dysfunction. Our study may provide novel strategies for the treatment of AngII-induced kidney injury.


Assuntos
Senescência Celular , Células Epiteliais , Exossomos , Túbulos Renais , Macrófagos , MicroRNAs , Telômero , MicroRNAs/genética , MicroRNAs/metabolismo , Senescência Celular/genética , Exossomos/metabolismo , Exossomos/genética , Animais , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Macrófagos/metabolismo , Túbulos Renais/patologia , Túbulos Renais/metabolismo , Camundongos , Telômero/genética , Telômero/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Masculino , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Fibrose/genética , Angiotensina II
4.
Fish Shellfish Immunol ; 152: 109789, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39053585

RESUMO

Bacillus genus, particularly Bacillus velezensis, is increasingly considered as viable alternatives to antibiotics in aquaculture due to their safety and probiotic potential. However, the specific mechanisms through which probiotic B. velezensis confers protection against Aeromonas hydrophila infection in fish remain poorly understood. This study delved into the multifaceted impacts of B. velezensis BV1704-Y on diverse facets of zebrafish health, including gut barrier function, immune response, oxidative stress, gut environment, microbiome composition, and disease resistance. Our findings demonstrate that supplementation with B. velezensis BV1704-Y significantly alleviated symptoms and reduced mortality in zebrafish infected with A. hydrophila. Furthermore, a notable reduction in the expression of pivotal immune-related genes, such as IL-1ß, IL6, and TNF-α, was evident in the gut and head kidney of zebrafish upon infection. Moreover, B. velezensis BV1704-Y supplementation resulted in elevated activity levels of essential antioxidant enzymes, including SOD, CAT, and GSH, in gut tissue. Notably, B. velezensis BV1704-Y positively modulated the structure and function of the intestinal microbiome, potentially enhancing immune response and resilience in zebrafish. Specifically, supplementation with B. velezensis BV1704-Y promoted the relative abundance of beneficial bacteria, such as Cetobacterium, which showed a noteworthy negative correlation with the expression of pro-inflammatory genes and a positive correlation with gut barrier-related genes. Altogether, our study suggests that B. velezensis BV1704-Y holds promise as an effective probiotic for protecting zebrafish against A. hydrophila infection, offering potential benefits for the aquaculture industry.


Assuntos
Aeromonas hydrophila , Bacillus , Resistência à Doença , Doenças dos Peixes , Infecções por Bactérias Gram-Negativas , Probióticos , Peixe-Zebra , Animais , Aeromonas hydrophila/fisiologia , Peixe-Zebra/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Infecções por Bactérias Gram-Negativas/veterinária , Doenças dos Peixes/imunologia , Probióticos/farmacologia , Probióticos/administração & dosagem , Bacillus/química , Bacillus/fisiologia , Resistência à Doença/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Ração Animal/análise , Dieta/veterinária , Imunidade Inata
5.
Environ Sci Technol ; 58(16): 7113-7123, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38547102

RESUMO

Low-pressure mercury lamps with high-purity quartz can emit both vacuum-UV (VUV, 185 nm) and UV (254 nm) and are commercially available and promising for eliminating recalcitrant organic pollutants. The feasibility of VUV/UV as a chemical-free oxidation process was verified and quantitatively assessed by the concept of H2O2 equivalence (EQH2O2), at which UV/H2O2 showed the same performance as VUV/UV for the degradation of trace organic contaminants (TOrCs). Although VUV showed superior H2O activation and oxidation performance, its performance highly varied as a function of light path length (Lp) in water, while that of UV/H2O2 proportionally decreased with decreasing H2O2 dose regardless of Lp. On increasing Lp from 1.0 to 3.0 cm, the EQH2O2 of VUV/UV decreased from 0.81 to 0.22 mM H2O2. Chloride and nitrate hardly influenced UV/H2O2, but they dramatically inhibited VUV/UV. The competitive absorbance of VUV by chloride and nitrate was verified as the main reason. The inhibitory effect was partially compensated by •OH formation from the propagation reactions of chloride or nitrate VUV photolysis, which was verified by kinetic modeling in Kintecus. In water with an Lp of 2.0 cm, the EQH2O2 of VUV/UV decreased from 0.43 to 0.17 mM (60.8% decrease) on increasing the chloride concentration from 0 to 15 mM and to 0.20 mM (53.5% decrease) at 4 mM nitrate. The results of this study provide a comprehensive understanding of VUV/UV oxidation in comparison to UV/H2O2, which underscores the suitability and efficiency of chemical-free oxidation with VUV/UV.


Assuntos
Peróxido de Hidrogênio , Compostos Orgânicos , Oxirredução , Raios Ultravioleta , Peróxido de Hidrogênio/química , Compostos Orgânicos/química , Fotólise , Poluentes Químicos da Água/química , Nitratos/química
6.
Anal Bioanal Chem ; 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38358531

RESUMO

α-Glucosidase (α-Glu) is implicated in the progression and pathogenesis of type II diabetes (T2D). In this study, we developed a rapid colorimetric technique using platinum nanoparticles stabilized by chitosan (Ch-PtNPs) to detect α-Glu activity and its inhibitor. The Ch-PtNPs facilitate the conversion of 3,3',5,5'-tetramethylbenzidine (TMB) into oxidized TMB (oxTMB) in the presence of dissolved O2. The catalytic hydrolysis of 2-O-α-D-glucopyranosyl-L-ascorbic acid (AA-2G) by α-Glu produces ascorbic acid (AA), which reduces oxTMB to TMB, leading to the fading of the blue color. However, the presence of α-Glu inhibitors (AGIs) hinders the generation of AA, allowing Ch-PtNPs to re-oxidize colorless TMB back to blue oxTMB. This unique phenomenon enables the colorimetric detection of α-Glu activity and AGIs. The linear range for α-Glu was found to be 0.1-1.0 U mL-1 and the detection limit was 0.026 U mL-1. Additionally, the half-maximal inhibition value (IC50) for acarbose, an α-Glu inhibitor, was calculated to be 0.4769 mM. Excitingly, this sensing platform successfully detected α-Glu activity in human serum samples and effectively screened AGIs. These promising findings highlight the potential application of the proposed strategy in clinical diabetes diagnosis and drug discovery.

7.
J Neuroeng Rehabil ; 21(1): 120, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026279

RESUMO

BACKGROUND: The contribution of cholinergic degeneration to gait disturbance in Parkinson's disease (PD) is increasingly recognized, yet its relationship with dopaminergic-resistant gait parameters has been poorly investigated. We investigated the association between comprehensive gait parameters and cholinergic nucleus degeneration in PD. METHODS: This cross-sectional study enrolled 84 PD patients and 69 controls. All subjects underwent brain structural magnetic resonance imaging to assess the gray matter density (GMD) and volume (GMV) of the cholinergic nuclei (Ch123/Ch4). Gait parameters under single-task (ST) and dual-task (DT) walking tests were acquired using sensor wearables in PD group. We compared cholinergic nucleus morphology and gait performance between groups and examined their association. RESULTS: PD patients exhibited significantly decreased GMD and GMV of the left Ch4 compared to controls after reaching HY stage > 2. Significant correlations were observed between multiple gait parameters and bilateral Ch123/Ch4. After multiple testing correction, the Ch123/Ch4 degeneration was significantly associated with shorter stride length, lower gait velocity, longer stance phase, smaller ankle toe-off and heel-strike angles under both ST and DT condition. For PD patients with HY stage 1-2, there were no significant degeneration of Ch123/4, and only right side Ch123/Ch4 were corrected with the gait parameters. However, as the disease progressed to HY stage > 2, bilateral Ch123/Ch4 nuclei showed correlations with gait performance, with more extensive significant correlations were observed in the right side. CONCLUSIONS: Our study demonstrated the progressive association between cholinergic nuclei degeneration and gait impairment across different stages of PD, and highlighting the potential lateralization of the cholinergic nuclei's impact on gait impairment. These findings offer insights for the design and implementation of future clinical trials investigating cholinergic treatments as a promising approach to address gait impairments in PD.


Assuntos
Transtornos Neurológicos da Marcha , Imageamento por Ressonância Magnética , Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/fisiopatologia , Doença de Parkinson/diagnóstico por imagem , Masculino , Feminino , Idoso , Estudos Transversais , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/fisiopatologia , Pessoa de Meia-Idade , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Neurônios Colinérgicos/patologia , Núcleo Basal de Meynert/diagnóstico por imagem
8.
J Youth Adolesc ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39033221

RESUMO

Numerous studies have investigated the relationship between social support and problematic mobile phone use among adolescents, yet a definitive consensus remains elusive. The high prevalence of problematic mobile phone use among children and adolescents requires urgent clarity on this issue. However, previous meta-analyses on this topic have primarily focused on college students, overlooking this association in younger age groups. The present study thus concentrated on children and adolescents, conducting a three-level meta-analysis to combine existing research findings and analyze various moderators to identify sources of research heterogeneity. A systematic literature search retrieved a total of 33 studies with 135 effect sizes for this meta-analysis, and 25,537 students (53.83% female, age range 7-19, grades range 3rd-12th) were included. The results showed a negative correlation (r = -0.139) between social support and problematic mobile phone use in children and adolescents. Age, social support measurement, sources of social support, and symptoms of problematic mobile phone use were found to have a significant moderating influence. Specifically, social support showed a stronger negative correlation with problematic mobile phone use in older adolescents compared to their younger counterparts. The correlation was more pronounced when using the Multidimensional Scale of Perceived Social Support than other scales. Family support exhibited a stronger negative correlation with problematic mobile phone use compared to other sources of support. Among the symptoms of problematic mobile phone use, the inability to control craving has the strongest negative correlation with social support. This meta-analysis suggested that providing more social support, particularly in the form of family support, during the development of children and adolescents may help alleviate problematic mobile phone use.

9.
Zhongguo Zhong Yao Za Zhi ; 49(2): 518-533, 2024 Jan.
Artigo em Zh | MEDLINE | ID: mdl-38403327

RESUMO

The efficacy and safety of different Chinese patent medicines in the treatment of coronary heart disease complicated with heart failure were evaluated by network Meta-analysis. The randomized controlled trial(RCT) of Chinese patent medicines for coronary heart disease complicated with heart failure was retrieved from CNKI, Wanfang, VIP, SinoMed, PubMed, Web of Science, EMbase, and Cochrane Library with the time interval from inception to July 5, 2023. The quality of the included RCT was evaluated by the Cochrane's risk of bias assessment tool, and a network Meta-analysis was performed in Stata 16.0. Finally, a total of 82 RCTs were included, involving 9 298 patients and 11 Chinese patent medicines. Network Meta-analysis yielded the following results based on the surface under the cumulative ranking curve(SUCRA).(1)In terms of improving the clinical response rate, the top three interventions were Qishen Yiqi Dripping Pills + conventional western medicine, Zhenyuan Capsules + conventional western medicine, and Tongxinluo Capsules + conventional western medicine.(2) In terms of increasing left ventricular ejection fraction(LVEF), the top three interventions were Shexiang Baoxin Pills + conventional western medicine, Compound Danshen Dripping Pills + conventional western medicine, and Tongxinluo Capsules + conventional western medicine.(3) In terms of reducing left ventricular end-diastolic diameter(LVEDD), the top three interventions were Shexiang Tongxin Dripping Pills + conventional western medicine, Tongxinluo Capsules + conventional western medicine, and Shexiang Baoxin Pills + conventional western medicine.(4) In terms of reducing N-terminal pro-brain natriuretic peptide(NT-proBNP), the top three interventions were Shexiang Baoxin Pills + conventional western medicine, Qi-shen Yiqi Dripping Pills + conventional western medicine, and Compound Danshen Dripping Pills + conventional western medicine.(5) In terms of reducing hyper-sensitive C-reactive protein(hs-CRP), the top three interventions were Naoxintong Capsules + conventional western medicine, Shexiang Baoxin Pills + conventional western medicine, and Compound Danshen Dripping Pills + conventional western medicine.(6) In terms of increasing the distance of the six-minute walking trail(6MWT), the top three interventions were Zhen-yuan Capsules + conventional western medicine, Qili Qiangxin Capsules + conventional western medicine, and Qishen Yiqi Dripping Pills + conventional western medicine. The results showed that Chinese patent medicines combined with conventional western medicine can effectively improve the clinical response rate, LVEF, and 6MWT and reduce LVEDD, NT-proBNP, and hs-CRP. However, due to the overall low quality of the articles included and the few articles of some Chinese patent medicines, direct comparison between diffe-rent Chinese patent medicines remains to be carried out and the results need to be further verified.


Assuntos
Doença das Coronárias , Medicamentos de Ervas Chinesas , Insuficiência Cardíaca , Humanos , Metanálise em Rede , Medicamentos sem Prescrição/uso terapêutico , Proteína C-Reativa , Volume Sistólico , Função Ventricular Esquerda , Medicamentos de Ervas Chinesas/uso terapêutico , Doença das Coronárias/complicações , Doença das Coronárias/tratamento farmacológico , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/tratamento farmacológico
10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 48(11): 1746-1752, 2023 Nov 28.
Artigo em Inglês, Zh | MEDLINE | ID: mdl-38432866

RESUMO

Ulcerative colitis (UC) is an inflammatory bowel disease induced by multiple factors, which causes abnormal activation of intestinal immune cells and excessive release of antibodies and inflammatory factors, repeatedly damaging the intestinal mucosa. Macrophages, as innate intestinal immune cells, often maintain the balance of M1/M2 macrophages polarization to normalize the regression inflammation, and the imbalance of their polarization will cause repeated damage of intestinal mucosa and persistent inflammation, which is a main cause of UC. Nuclear factor E2-related factor 2 (Nrf2), as an important regulator of antioxidant and anti-inflammatory, is often used as a target for the treatment of autoimmune diseases.Nrf2 alleviates intestinal high oxidative stress and inflammatory factors by balancing macrophage polarization, which may be of great significance for the prevention and treatment of UC. Summarizing the mechanism of macrophage polarization imbalance on the course of UC and the possible regulatory mechanism of Nrf2 may provide basis for the development of UC targeted therapeutic drugs.


Assuntos
Colite Ulcerativa , Doenças Inflamatórias Intestinais , Humanos , Inflamação , Macrófagos , Fator 2 Relacionado a NF-E2
13.
J Sch Health ; 94(1): 23-36, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37697677

RESUMO

BACKGROUND: Since 2002, the Chinese Ministry of Education has conducted reform in the physical education (PE) curriculums of schools in China, with a focus on shifting from sports skills to regular participation in physical activity (PA) and promoting health. The aim of the study, therefore, is to examine the effects of school PE on the exercise habits of children and adolescents in China over time. METHODS: Data based on 5941 observations of 3708 individuals aged 6 to 17 were collected from the China Health and Nutrition Survey (CHNS) for the period 2004 to 2015. The data were analyzed using the fixed-effect Logit model and the random-effect Tobit model. RESULTS: The likelihood of exercising outside of school is 20.2% higher for students who have school PE than those who do not. Our study found that increasing the duration of PE at school by 100%, increases the duration of out-of-school PA by 22.3%. The variety of the types of sports schools offer encourages students to participate in out-of-school physical activity. The likelihood of students exercising outside of school increases by 5.6% when 1 more exercise type is provided in school PE. In addition, soccer, basketball, badminton, and volleyball education increases students' participation in after-school exercises. Soccer and basketball education, in particular, improves the duration of after-school PA. CONCLUSIONS: To form exercise habits in children and adolescents, we encourage the promotion of a variety of physical activities in schools, especially team sports such as soccer and basketball.


Assuntos
Exercício Físico , Educação Física e Treinamento , Criança , Humanos , Adolescente , Instituições Acadêmicas , Inquéritos Nutricionais , Hábitos
14.
J Health Psychol ; : 13591053241273655, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39175156

RESUMO

This study was aimed to examine the moderated mediating effects of exercise self-efficacy and fear of movement on the relationship between fatigue and quality of life in patients with heart failure. A total of 305 patients with heart failure were enrolled in this cross-sectional study. The results showed that fear of movement significantly mediated the relationship between fatigue and quality of life, indicating that relieving fear of movement may be beneficial to improve quality of life. Furthermore, exercise self-efficacy negatively moderated the mediating effect of fear of movement on the relationship between fatigue and physical health-related quality of life. It is suggesting that improving exercise self-efficacy may provide opportunities to buffer the negative effect of fear of movement on physical health-related quality of life in patients with heart failure, especially for those with fatigue. The findings provide additional strategies to optimize quality of life management in patients with heart failure.

15.
Artigo em Inglês | MEDLINE | ID: mdl-39136206

RESUMO

BACKGROUND: The adverse health effects of incarceration are well-documented, impacting individuals throughout their life course. However, the influence of a history of incarceration on end-of-life (EOL) experiences remains unexplored. This study aims to examine how prior incarceration affects individuals' experiences and care needs as they approach the end of life. METHODS: Leveraging the Health and Retirement Study, we conducted secondary analyses on 1,710 individuals who participated between 2012-2018. Through retrospective cohort analysis, we explored the association between incarceration history and EOL care, focusing on pain and symptom burden. RESULTS: Analyses showed that individuals with a history of incarceration experienced significantly higher levels of pain (65% reported "moderate" or "severe" pain) compared to non-incarcerated individuals (50%; AOR = 1.45, 95% CI: 1.22-1.71, p < 0.001). Additionally, the symptom burden index revealed formerly incarcerated individuals had a higher average symptom score (2.8 vs. 2.1; ß = 0.7, 95% CI: 0.5-0.9, p < 0.001), indicating a greater range of symptoms in their final year of life. These disparities persisted after adjusting for demographic, health, and socioeconomic variables. CONCLUSION: This study reveals that a history of incarceration significantly impacts EOL experiences, with formerly incarcerated individuals facing higher levels of pain and a greater symptom burden compared to non-incarcerated individuals. This underscores the need for tailored palliative care to address the unique needs of this vulnerable population. This research highlights a critical area for intervention and calls for healthcare systems to adapt their practices to better serve those with incarceration histories.

16.
Biomimetics (Basel) ; 9(6)2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38921226

RESUMO

As technology rapidly evolves, the application of bipedal robots in various environments has widely expanded. These robots, compared to their wheeled counterparts, exhibit a greater degree of freedom and a higher complexity in control, making the challenge of maintaining balance and stability under changing wind speeds particularly intricate. Overcoming this challenge is critical as it enables bipedal robots to sustain more stable gaits during outdoor tasks, thereby increasing safety and enhancing operational efficiency in outdoor settings. To transcend the constraints of existing methodologies, this research introduces an adaptive bio-inspired exploration framework for bipedal robots facing wind disturbances, which is based on the Deep Deterministic Policy Gradient (DDPG) approach. This framework allows the robots to perceive their bodily states through wind force inputs and adaptively modify their exploration coefficients. Additionally, to address the convergence challenges posed by sparse rewards, this study incorporates Hindsight Experience Replay (HER) and a reward-reshaping strategy to provide safer and more effective training guidance for the agents. Simulation outcomes reveal that robots utilizing this advanced method can more swiftly explore behaviors that contribute to stability in complex conditions, and demonstrate improvements in training speed and walking distance over traditional DDPG algorithms.

17.
Nanomaterials (Basel) ; 14(13)2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38998712

RESUMO

Magnetic metal absorbing materials have exhibited excellent absorptance performance. However, their applications are still limited in terms of light weight, low thickness and wide absorption bandwidth. To address this challenge, we design a broadband and low-profile multilayer absorber using cobalt-iron (CoFe) alloys doped with rare earth elements (REEs) lanthanum (La) and Neodymium (Nd). An improved estimation of distribution algorithm (IEDA) is employed in conjunction with a mathematical model of multilayer absorbing materials (MAMs) to optimize both the relative bandwidth with reflection loss (RL) below -10 dB and the thickness. Firstly, the absorption performance of CoFe alloys doped with La/Nd with different contents is analysed. Subsequently, IEDA is introduced based on a mathematical model to achieve an optimal MAM design that obtains a balance between absorption bandwidth and thickness. To validate the feasibility of our proposed method, a triple-layer MAM is designed and optimized to exhibit wide absorption bandwidth covering C, X, and Ku bands (6.16-12.82 GHz) and a total thickness of 2.39 mm. Then, the electromagnetic (EM) absorption mechanisms of the triple-layer MAMs are systematically investigated. Finally, the triple-layer sample is further fabricated and measured. The experimental result is in good agreement with the simulated result. This paper presents a rapid and efficient optimization method for designing MAMs, offering promising prospects in microwave applications, such as radar-stealth technology, EM shielding, and reduced EM pollution for electronic devices.

18.
Lab Anim Res ; 40(1): 18, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741131

RESUMO

Community-acquired respiratory infection is the commonest cause of sepsis presenting to emergency departments. Yet current experimental animal models simulate peritoneal sepsis with intraperitoneal (I.P.) injection of lipopolysaccharide (LPS) as the predominant route. We aimed to compare the progression of organ injury between I.P. LPS and intranasal (I.N.) LPS in order to establish a better endotoxemia murine model of respiratory sepsis. Eight weeks old male BALB/c mice received LPS-Escherichia coli doses at 0.15, 1, 10, 20, 40 and 100 mg per kg body weight (e.g. LPS-10 is a dose of 10 mg/kg body weight). Disease severity was monitored by a modified Mouse Clinical Assessment Score for Sepsis (M-CASS; range 0-21). A M-CASS score ≥ 10 or a weight reduction of ≥ 20%, was used as a criterion for euthanasia. The primary outcome was the survival rate (either no death or no need for euthanasia). The progression of disease was specified as M-CASS, body weight, blood glucose, histopathological changes to lung, liver, spleen, kidney, brain and heart tissues. Survival rate in I.P. LPS-20 mice was 0% (2/3 died; 1/3 euthanized with M-CASS > 10) at 24 h. Survival rate in all doses of I.N. LPS was 100% (20/20; 3-4 per group) at 96 h. 24 h mean M-CASS post-I.P. LPS-10 was 6.4/21 significantly higher than I.N. LPS-10 of 1.7/21 (Unpaired t test, P < 0.05). Organ injury was present at 96 h in the I.P. LPS-10 group: lung (3/3; 100%), spleen (3/3; 100%) and liver (1/3; 33%). At 24 h in the I.P. LPS-20 group, kidney injury was observed in the euthanized mouse. At 96 h in the post-I.N. LPS-20 group, only lung injury was observed in 2/3 (67%) mice (Kruskal-Wallis test with Dunn's, P < 0.01). At 24 h in the post-I.N. LPS-100 group all (4/4) mice had evidence of lung injury. Variable doses of I.N. LPS in mice produced lung injury but did not produce sepsis. Higher doses of I.P. LPS induced multi-organ injury but not respiratory sepsis. Lethal models of respiratory virus, e.g., influenza A, might provide alternative avenues that can be explored in future research.

19.
Endocrine ; 85(1): 238-249, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38191984

RESUMO

PURPOSE: The four and a half LIM domain protein 1 (FHL1) has been found to act as a tumor suppressor in several cancers. However, the clinical and functional significance, as well as underlying molecular mechanisms of FHL1 in papillary thyroid cancer (PTC) are largely unknown. METHODS: Bioinformatics analyses, qRT-PCR and Western blotting were used to investigate the expression of FHL1 in PTC. Cell proliferation was measured using CCK8, Edu, colony formation, and flow cytometry assays. Cell migration and invasion were examined by wound healing and Transwell assays. qRT-PCR, Western blot, immunofluorescence and Top/Fop reporter assays were performed to assess the underlying mechanisms. RESULTS: FHL1 expression was significantly downregulated in PTC. FHL1 downregulation negatively correlated with stage, T classification, and N classification of the patients. The downregulation of FHL1 is associated with poor prognosis. Overexpression of FHL1 inhibited PTC cells' proliferation, invasion, migration and Wnt/ß-catenin pathway activity. LiCl partially restored the inhibitory effects of FHL1 on aggressive phenotypes and Wnt/ß-catenin pathway activity of PTC cells. CONCLUSION: FHL1 is downregulated in PTC and its expression is associated with better clinical outcomes for patients with the disease. FHL1 acts as a tumor suppressor via, at least partially, suppressing Wnt/ß-catenin pathway.


Assuntos
Movimento Celular , Proliferação de Células , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas com Domínio LIM , Proteínas Musculares , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide , Via de Sinalização Wnt , Humanos , Via de Sinalização Wnt/fisiologia , Via de Sinalização Wnt/genética , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/genética , Proteínas com Domínio LIM/genética , Proteínas com Domínio LIM/metabolismo , Câncer Papilífero da Tireoide/patologia , Câncer Papilífero da Tireoide/genética , Câncer Papilífero da Tireoide/metabolismo , Proteínas Musculares/metabolismo , Proteínas Musculares/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Feminino , Linhagem Celular Tumoral , Masculino , Pessoa de Meia-Idade , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Adulto , Regulação para Baixo
20.
Microorganisms ; 12(5)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38792703

RESUMO

Intestinal barrier hyperpermeability, which is characterised by impaired tight junction proteins, is associated with a variety of gastrointestinal and systemic diseases. Therefore, maintaining intestinal barrier integrity is considered one of the effective strategies to reduce the risk of such disorders. This study aims to investigate the potential benefits of two probiotic strains (Lactiplantibacillus plantarum ST-III and Lacticaseibacillus rhamnosus KF7) on intestinal barrier function by using a physiologically relevant in vitro model of the intestinal epithelium. Our results demonstrate that both strains increased transepithelial electrical resistance, a measure of intestinal barrier integrity. Immunolocalisation studies indicated that this improvement in barrier function was not due to changes in the co-localisation of the tight junction (TJ) proteins ZO-1 and occludin. However, we observed several modifications in TJ-related genes in response to the probiotics, including the upregulation of transmembrane and cytosolic TJ proteins, as well as TJ signalling proteins. Gene expression modulation was strain- and time-dependent, with a greater number of differentially expressed genes and higher fold-change being observed in the L. plantarum ST-III group and at the latter timepoint. Further studies to investigate how the observed gene expression changes can lead to enhanced barrier function will aid in the development of probiotic foods to help improve intestinal barrier function.

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