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1.
J Environ Manage ; 354: 120263, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38387360

RESUMEN

Biogenic carbon emissions, including carbon dioxide (CO2) and methane (CH4), have emerged as a major concern during organic pollutant degradation within constructed wetlands (CWs). Since these organic compounds primarily originate from the photosynthetic fixation of atmospheric CO2, it potentially introduces uncertainty when assessing the greenhouse effect of biogenic carbon emissions in CWs based on direct field observations. To objectively assessing this effect, this study proposed a new strategy by quantifying CO2-equivalent (CO2-eq) changes as carbon passes through CWs and tested it in various types of CWs based on 64 literature records. The findings reveal that CWs can contribute to CO2-eq additions, yet are only responsible for 15.6% derived from direct field observations. The type of CWs plays a crucial role in these CO2-eq additions, with vertical flow CWs causing the lowest levels (6.8%), followed by surface flow CWs (14.2%). In contrast, horizontal flow CWs are associated with the strongest CO2-eq addition (25.7%). The findings provide new insights for the objective assessment of the greenhouse effect of biogenic carbon emissions in CWs, which will be beneficial for future life cycle assessment.


Asunto(s)
Contaminantes Ambientales , Humedales , Efecto Invernadero , Dióxido de Carbono/análisis , Metano , Óxido Nitroso/análisis
2.
Environ Sci Technol ; 57(36): 13356-13365, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37653579

RESUMEN

To understand the nanotoxicity effects on plants, it is necessary to systematically study the distribution of NPs in vivo. Herein, elemental and particle-imaging techniques were used to unravel the size effects of ZnO NPs on phytotoxicity. Small-sized ZnO NPs (5, 20, and 50 nm) showed an inhibitory effect on the length and biomass of rice (Oryza sativa L.) used as a model plant. ZnO NP nanotoxicity caused rice root cell membrane damage, increased the malondialdehyde content, and activated antioxidant enzymes. As a control, the same dose of Zn2+ salt did not affect the physiological and biochemical indices of rice, suggesting that the toxicity is caused by the entry of the ZnO NPs and not the dissolved Zn2+. Laser ablation inductively coupled plasma optical emission spectroscopy analysis revealed that ZnO NPs accumulated in the rice root vascular tissues of the rhizodermis and procambium. Furthermore, transmission electron microscopy confirmed that the NPs were internalized to the root tissues. These results suggest that ZnO NPs may exist in the rice root system and that their particle size could be a crucial factor in determining toxicity. This study provides evidence of the size-dependent phytotoxicity of ZnO NPs.


Asunto(s)
Oryza , Óxido de Zinc , Tamaño de la Partícula , Óxido de Zinc/toxicidad , Antioxidantes , Biomasa
3.
Environ Sci Technol ; 57(21): 8035-8043, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37200099

RESUMEN

Microplastics (MPs), as a new persistent pollutant, can be emitted and accumulated in urban environments, but there is no detailed information on the driving factors of MP pollution. In this study, through a large-scale wetland soil survey, the features of MPs were characterized in each urban area. The results showed an average abundance to be 379 n/kg in wetland soil. Polypropylene, fiber or fragment, and black color were common composition, shape, and color, respectively. The spatial distribution information showed that MP abundance was significantly relevant to the distance from the urban economic center. Furthermore, the correlation and regression analysis revealed that MP abundance was related to soil heavy metal and atmospheric particle (PM10 and PM2.5) concentrations (P < 0.05), while the promotion of socioeconomic activities (urbanization level, population density, etc.) may aggravate the pollution degree. Additionally, by using structural equation modeling, it was found that the urbanization level was the dominant factor driving the MP pollution degree, with a total effect coefficient of 0.49. Overall, this work provides multi-sided environmental information regarding MP pollution in urban ecosystems, which is significant for follow-up studies of MP pollution control and restoration.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos/análisis , Humedales , Ecosistema , Suelo , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis
4.
Environ Res ; 233: 116472, 2023 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-37348631

RESUMEN

Inland waters are significant sources of atmospheric greenhouse gas (GHG) emissions. The thin boundary layer (TBL) model is often employed as a means of estimating GHG diffusion in inland waters based on gas transfer velocity (k) at the air-water interface, with k being subject to regulation by near-surface turbulence that is primarily driven by wind speed in many cases. This wind speed-based estimation of k (wind-k), however, can introduce substantial uncertainty for turbulent waterways where wind speed does not accurately represent overall turbulence. In this study, GHG diffusion in the Beijing-Hangzhou Grand Canal (China), the first and longest man-made canal in the world, was estimated using the TBL model, revealing that this model substantially underestimated GHG diffusion when relying on wind-k. Strikingly, the carbon dioxide, methane, and nitrous oxide diffusions were respectively underestimated by 159%, 162%, and 124% when using this model. These findings are significant for developing more reliable approaches to evaluate GHG emissions from inland waterways.


Asunto(s)
Gases de Efecto Invernadero , Humanos , Dióxido de Carbono/análisis , Viento , Metano/análisis , China , Óxido Nitroso , Efecto Invernadero
5.
J Med Internet Res ; 25: e46084, 2023 05 15.
Artículo en Inglés | MEDLINE | ID: mdl-37184899

RESUMEN

BACKGROUND: Scholars have used data from in-person interviews, administrative systems, and surveys for sexual violence research. Using Twitter as a data source for examining the nature of sexual violence is a relatively new and underexplored area of study. OBJECTIVE: We aimed to perform a scoping review of the current literature on using Twitter data for researching sexual violence, elaborate on the validity of the methods, and discuss the implications and limitations of existing studies. METHODS: We performed a literature search in the following 6 databases: APA PsycInfo (Ovid), Scopus, PubMed, International Bibliography of Social Sciences (ProQuest), Criminal Justice Abstracts (EBSCO), and Communications Abstracts (EBSCO), in April 2022. The initial search identified 3759 articles that were imported into Covidence. Seven independent reviewers screened these articles following 2 steps: (1) title and abstract screening, and (2) full-text screening. The inclusion criteria were as follows: (1) empirical research, (2) focus on sexual violence, (3) analysis of Twitter data (ie, tweets or Twitter metadata), and (4) text in English. Finally, we selected 121 articles that met the inclusion criteria and coded these articles. RESULTS: We coded and presented the 121 articles using Twitter-based data for sexual violence research. About 70% (89/121, 73.6%) of the articles were published in peer-reviewed journals after 2018. The reviewed articles collectively analyzed about 79.6 million tweets. The primary approaches to using Twitter as a data source were content text analysis (112/121, 92.5%) and sentiment analysis (31/121, 25.6%). Hashtags (103/121, 85.1%) were the most prominent metadata feature, followed by tweet time and date, retweets, replies, URLs, and geotags. More than a third of the articles (51/121, 42.1%) used the application programming interface to collect Twitter data. Data analyses included qualitative thematic analysis, machine learning (eg, sentiment analysis, supervised machine learning, unsupervised machine learning, and social network analysis), and quantitative analysis. Only 10.7% (13/121) of the studies discussed ethical considerations. CONCLUSIONS: We described the current state of using Twitter data for sexual violence research, developed a new taxonomy describing Twitter as a data source, and evaluated the methodologies. Research recommendations include the following: development of methods for data collection and analysis, in-depth discussions about ethical norms, exploration of specific aspects of sexual violence on Twitter, examination of tweets in multiple languages, and decontextualization of Twitter data. This review demonstrates the potential of using Twitter data in sexual violence research.


Asunto(s)
Delitos Sexuales , Medios de Comunicación Sociales , Humanos , Comunicación , Aprendizaje Automático , Encuestas y Cuestionarios
6.
J Med Internet Res ; 25: e47217, 2023 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-38113097

RESUMEN

BACKGROUND: Chatbots have become ubiquitous in our daily lives, enabling natural language conversations with users through various modes of communication. Chatbots have the potential to play a significant role in promoting health and well-being. As the number of studies and available products related to chatbots continues to rise, there is a critical need to assess product features to enhance the design of chatbots that effectively promote health and behavioral change. OBJECTIVE: This scoping review aims to provide a comprehensive assessment of the current state of health-related chatbots, including the chatbots' characteristics and features, user backgrounds, communication models, relational building capacity, personalization, interaction, responses to suicidal thoughts, and users' in-app experiences during chatbot use. Through this analysis, we seek to identify gaps in the current research, guide future directions, and enhance the design of health-focused chatbots. METHODS: Following the scoping review methodology by Arksey and O'Malley and guided by the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) checklist, this study used a two-pronged approach to identify relevant chatbots: (1) searching the iOS and Android App Stores and (2) reviewing scientific literature through a search strategy designed by a librarian. Overall, 36 chatbots were selected based on predefined criteria from both sources. These chatbots were systematically evaluated using a comprehensive framework developed for this study, including chatbot characteristics, user backgrounds, building relational capacity, personalization, interaction models, responses to critical situations, and user experiences. Ten coauthors were responsible for downloading and testing the chatbots, coding their features, and evaluating their performance in simulated conversations. The testing of all chatbot apps was limited to their free-to-use features. RESULTS: This review provides an overview of the diversity of health-related chatbots, encompassing categories such as mental health support, physical activity promotion, and behavior change interventions. Chatbots use text, animations, speech, images, and emojis for communication. The findings highlight variations in conversational capabilities, including empathy, humor, and personalization. Notably, concerns regarding safety, particularly in addressing suicidal thoughts, were evident. Approximately 44% (16/36) of the chatbots effectively addressed suicidal thoughts. User experiences and behavioral outcomes demonstrated the potential of chatbots in health interventions, but evidence remains limited. CONCLUSIONS: This scoping review underscores the significance of chatbots in health-related applications and offers insights into their features, functionalities, and user experiences. This study contributes to advancing the understanding of chatbots' role in digital health interventions, thus paving the way for more effective and user-centric health promotion strategies. This study informs future research directions, emphasizing the need for rigorous randomized control trials, standardized evaluation metrics, and user-centered design to unlock the full potential of chatbots in enhancing health and well-being. Future research should focus on addressing limitations, exploring real-world user experiences, and implementing robust data security and privacy measures.


Asunto(s)
Salud Digital , Promoción de la Salud , Humanos , Comunicación , Benchmarking , Lista de Verificación , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
J Sci Food Agric ; 103(13): 6706-6718, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37276023

RESUMEN

BACKGROUND: Alfalfa (Medicago sativa L.) has been used widely in preparing silage. However, forage legumes are prone to contamination by spoilage bacteria during fermentation. Nisin has broad-spectrum antibacterial properties and has been applied as an inhibitor of rumen methane emissions. However, little research has been carried out on the application of nisin in silage. This study therefore aimed to investigate the impacts of different nisin concentrations on the bacterial community and fermentation dynamics, in vitro ruminal fermentation characteristics, microbiota, and methane emissions of alfalfa silage. RESULTS: The detection limits of organic acid in nisin-treated silages were not reached in 0.09 g kg-1 nisin (0.09 level) from days 1 to 7 of ensiling. With increasing nisin concentrations, the silage dry matter increased linearly (P < 0.05), and dry matter loss decreased linearly (P < 0.05). Moreover, both the 0.06 g kg-1 nisin (0.06 level) and 0.09 level treatments increased the relative abundance of Pediococcus acidilactici during ensiling. Concurrently, as the nisin concentrations increased, ruminal methane production decreased linearly (P < 0.05), while the relative abundances of ruminal Succinivibrio, Fibrobacter succinogenes and Ruminobacter amylophilus increased linearly (P < 0.05). The populations of ruminal total bacteria, methanogens, protozoa, and fungi decreased linearly with increasing nisin concentrations (P < 0.05). CONCLUSION: The addition of nisin delayed the fermentation process, preserved more nutrients in alfalfa silage, and promoted fermentation dominated by P. acidilactici in the late phase of ensiling. Moreover, nisin reduced in vitro rumen methane emissions without adverse effects on dry matter digestibility. © 2023 Society of Chemical Industry.


Asunto(s)
Microbiota , Nisina , Animales , Femenino , Ensilaje/análisis , Leche/química , Medicago sativa/microbiología , Lactancia , Dieta , Rumen/metabolismo , Fermentación , Metano/metabolismo , Nisina/farmacología , Digestión , Bacterias
8.
Appl Opt ; 61(27): 7899-7911, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-36255910

RESUMEN

Rough manual interpretation distance cannot keep up with the intelligent detection and interpretation of sewer pipe defects. We present an automatic location method for the accurate longitudinal distance of the structural defects in sewer pipes via a pinhole-based defect monocular ranging model via image processing of pipe diameters. Then the model verification experiment is undertaken through a comparison with the actual data of the pipe size and the camera parameters. The results of the experiment demonstrate an improved accuracy of this method of defect spatial location and the robustness and stability of the model of the accurate acquisition of the longitudinal distance based on the monocular ranging between the inspection robot and the pipe defect.

9.
Ecotoxicol Environ Saf ; 246: 114194, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36252513

RESUMEN

The potential toxicity of microplastic (MPs) to organisms has attracted extensive attention. However, due to the subacute toxicity of MPs, the biological effect is hard to verify in short-term exposure experiment. Here, by tracking the dynamics of gut microbes, mice model was utilized to evaluate the toxicity of compositional MPs (PE, PET, PP, PS and PVC). After 7 days digestive exposure, the physiological indicators were normal as the control group that the body weight and serum cholesterol levels were insignificant change. Whereas, through histopathological examination, all the treatment groups suffered colon tissue damage, among which PS had the most inflammatory cells. Moreover, the high-throughput sequencing results revealed great variation of intestinal flora in treated mice. The ratio of Bacteroidetes and Firmicutes in PE, PET and PP treatment groups heighten, and the relative abundance of Ruminococcaceae and Lachnospiraceae increased significantly at family levels. At the genus level, Alistipes bacteria in PS treatment group significantly decreased that is associated with obesity risk. It indicated that MPs induced inflammatory response would further interfere the dynamics of intestinal flora causing health effect in living organisms. This work shed light on MPs toxicity in short-term exposure and supplied research paradigm of MPs health risk assessment.


Asunto(s)
Microbioma Gastrointestinal , Microplásticos , Ratones , Animales , Plásticos , Bacterias/genética , Digestión
10.
Nutr Metab Cardiovasc Dis ; 30(6): 967-976, 2020 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-32249138

RESUMEN

BACKGROUND AND AIMS: Plant-based protein intake is associated with all-cause and/or cardiovascular disease (CVD) mortality in general population, but such data are scarce in dialysis patients. Thus, we examined the associations of plant-based protein-total protein ratio with all-cause and CVD mortality in patients on peritoneal dialysis (PD). METHODS AND RESULTS: The study enrolled 884 incident patients who started PD between October 2002 and August 2014. All demographic and laboratory data were recorded at baseline. Repeated measurements for laboratory and nutrition parameters were recorded at regular intervals and thus calculated as time-averaged values. Multivariable Cox regression models were used to estimate the hazard ratio (HR) of plant-based protein-total protein ratio and mortality based on baseline and time-averaged covariates, respectively. There were 437 (49%) patients died during a mean follow-up period of 45 months, of which 178 (40.8%) were due to CVD. Each 10% in increase in time-averaged plant-based protein-total protein ratio was associated with a reduction of 71% (95% CI, 90%-14%) and 89% (95% CI, 98%-29%) for all-cause and CVD mortality, respectively. Based on examination on interactive effects, we further found both baseline and time-averaged plant-based protein-total protein ratio were inversely associated with all-cause and CVD mortality in the subgroups of female, age ≥60 years, and albumin >35 g/L. CONCLUSIONS: The present study suggested that a diet with a higher plant-based protein-total protein ratio is associated with lower all-cause and CVD mortality in PD patients, and is more significant in female and elderly patients, and those without hypoalbuminemia.


Asunto(s)
Enfermedades Cardiovasculares/mortalidad , Fallo Renal Crónico/terapia , Diálisis Peritoneal/mortalidad , Proteínas de Vegetales Comestibles/administración & dosificación , Adulto , Factores de Edad , Anciano , Beijing/epidemiología , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/prevención & control , Causas de Muerte , Comorbilidad , Femenino , Humanos , Hipoalbuminemia/mortalidad , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/mortalidad , Masculino , Persona de Mediana Edad , Estado Nutricional , Diálisis Peritoneal/efectos adversos , Proteínas de Vegetales Comestibles/efectos adversos , Factores Protectores , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Factores de Tiempo , Resultado del Tratamiento
11.
Int J Cancer ; 145(7): 1946-1957, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30873585

RESUMEN

Cancer-associated fibroblasts (CAFs) play a key role in orchestrating the tumor malignant biological properties within tumor microenvironment and evidences demonstrate that CAFs are a critical regulator of tumoral immunosuppression of the T cell response. However, the functions and regulation of CAFs in the expression of programmed death-ligand 1 (PD-L1) in melanoma and colorectal carcinoma (CRC) are not completely understood. Herein, by scrutinizing the expression of α-SMA and PD-L1 in melanoma and CRC tissues, we found that CAFs was positive correlated with PD-L1 expression. Further analyses showed that CAFs promoted PD-L1 expression in mice tumor cells. By detecting a majority of cytokines expression in normal mice fibroblasts and CAFs, we determined that CXCL5 was abnormal high expression in CAFs and the immunohistochemistry and in situ hybridization confirmed that were CAFs which were expressing CXCL5. In addition, CXCL5 promoted PD-L1 expression in B16, CT26, A375 and HCT116. The silencing of CXCR2, the receptor of CXCL5, inhibited the PD-L1 expression induced by CAFs in turn. Functionally, CXCL5 derived by CAFs promoted PD-L1 expression in mice tumor cells through activating PI3K/AKT signaling. LY294002, the inhibitor of PI3K, confirmed that CXCL5 forested an immunosuppression microenvironment by promoting PD-L1 expression via PI3K/AKT signaling. Meanwhile, the B16/CT26 xenograft tumor models were used and both CXCR2 and p-AKT were found to be positively correlated with PD-L1 in the xenograft tumor tissues. The immunosuppressive action of CAFs on tumor cells is probably reflective of them being a potential therapeutic biomarker for melanoma and CRC.


Asunto(s)
Antígeno B7-H1/metabolismo , Fibroblastos Asociados al Cáncer/metabolismo , Quimiocina CXCL5/metabolismo , Neoplasias Colorrectales/metabolismo , Melanoma Experimental/metabolismo , Actinas/metabolismo , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Células HCT116 , Humanos , Sistema de Señalización de MAP Quinasas , Melanoma Experimental/genética , Ratones , Trasplante de Neoplasias , Fosfatidilinositol 3-Quinasas/metabolismo , Regulación hacia Arriba
12.
Br J Nutr ; 122(9): 996-1005, 2019 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-31322103

RESUMEN

Higher fibre intake reduced all-cause and cardiovascular mortality among healthy population, but such data in dialysis patients are limited. We aimed to examine these associations in patients on peritoneal dialysis (PD). This single-centre prospective cohort study enrolled 881 incident PD patients between October 2002 and August 2014. All patients were followed until death, transfer to haemodialysis, renal transplantation or until being censored in June 2018. Demographic data were collected at baseline. Biochemical, dietary and nutrition data were examined at baseline and thereafter at regular intervals to calculate the average values throughout the study. The outcomes were defined as all-cause and cardiovascular death. Cox proportional regression models were applied to explore the relationship between fibre intake and outcomes. Participants with higher fibre intake were more likely to be younger, male and have better residual renal function and serum lipids at baseline. They were prone to maintain better nutrient status, higher blood pressure and lower inflammatory status at baseline and afterwards. Neither baseline nor time-averaged fibre intake did show protective effects on all-cause mortality after multivariate adjustment in the whole cohort. Among non-diabetic PD patients, an independent association between fibre intake and all-cause mortality was found, in which each 1 g/d increase in time-averaged fibre intake correlated to 13 % of reduction in all-cause mortality. We did not observe any benefits of fibre intake in the CVD mortality for both whole cohort and subgroups. The present study revealed that higher dietary fibre intake appeared to have a protective effect on all-cause mortality in non-diabetic PD patients, which suggest that PD patients should be encouraged to eat a diet rich in fibres.


Asunto(s)
Fibras de la Dieta , Fallo Renal Crónico/mortalidad , Fallo Renal Crónico/terapia , Diálisis Peritoneal , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estado Nutricional , Factores de Riesgo
13.
Ren Fail ; 40(1): 259-264, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29619872

RESUMEN

OBJECTIVE: To investigate the association of short-term blood pressure variability (BPV) with cardiovascular mortality in hemodialysis (HD) patients, using a reliable index called average real variability (ARV), and to assess the factors associated with ARV in incident HD population. METHODS: A total of 103 HD patients were recruited, with 44-h ambulatory blood pressure monitoring performed after the midweek HD session. Systolic BPV was assessed by SD, coefficient of variation (CV), and ARV, respectively. Laboratory data were obtained from blood samples before the midweek HD. All patients were followed up for 24 months. RESULTS: According to the median of BPV indices, the comparisons between patients with the low and high values were conducted. Kaplan-Meier analysis showed the survival curves corresponding to median of SD and CV exhibit similar performance for the low and high groups (p = .647, p = .098, respectively). In contrast, patients with higher ARV had a lower survival rate than those with lower ARV (77.8% vs. 98.0%, p = .002). After adjustment for demographics and clinical factors, ARV (HR: 1.143; 95% CI: 1.022-1.279, p = .019) and high-sensitivity C-reactive protein (HR: 1.394; 95% CI: 1.025-1.363, p = .021) were associated with increased risk of cardiovascular mortality in HD patients. Age and interdialytic weight gain (IDWG) were related factors for ARV (ß = 0.065, p = .005; ß = 0.825, p = .003, respectively). CONCLUSIONS: Greater ARV was independently associated with increased risk of cardiovascular mortality in HD patients. Age and IDWG were independent related factors for ARV.


Asunto(s)
Presión Sanguínea , Enfermedades Cardiovasculares/mortalidad , Fallo Renal Crónico/mortalidad , Diálisis Renal , Factores de Edad , Anciano , Monitoreo Ambulatorio de la Presión Arterial , Proteína C-Reactiva/análisis , Enfermedades Cardiovasculares/sangre , Enfermedades Cardiovasculares/etiología , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Fallo Renal Crónico/sangre , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Medición de Riesgo/métodos , Factores de Riesgo , Aumento de Peso
14.
Molecules ; 23(6)2018 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-29882920

RESUMEN

Curcumin is acknowledged for its antioxidant, anti-inflammatory, anti-cancer, and wound-healing properties. However, the biological activity and the molecular mechanisms of T59, which is a new derivative of curcumin, are not fully understood. The present study was aimed to determine the cytoxicity role of T59 in human lung cancer and the molecular mechanisms. Cytotoxicity and cell apoptosis effects induced by T59 were determined by MTT, AO staining, Annexin V, and JC-1. Compared with curcumin, T59 exerted more effective cytotoxicity and cell apoptosis effects in A549 and H1975. With the decreasing level of the mitochondrion membrane potential, the generation of reactive oxygen species (ROS) was increased and induced by T59. Furthermore, the expressions of cleaved-caspase-3 and Bax were increased, which were reversed by NAC mainly through the PI3K/AKT signaling pathway. Our results suggested that T59 has the potential for further investigation and study to act as an anti-cancer therapeutic against human lung cancer.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Curcumina/análogos & derivados , Neoplasias Pulmonares/patología , Especies Reactivas de Oxígeno/metabolismo , Acetilcisteína/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
15.
Cancer Immunol Immunother ; 66(3): 355-366, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27915371

RESUMEN

Myeloid-derived suppressor cells (MDSC) have been identified as a population of immature myeloid cells that suppress anti-tumor immunity. MDSC are increased in tumor-bearing hosts; thus, depletion of MDSC may enhance anti-tumor immunity. Histone deacetylase inhibitors (HDACi) are chemical agents that are primarily used against hematologic malignancies. The ability of these agents to modulate anticancer immunity has recently been extensively studied. However, the effect of HDACi on MDSC has remained largely unexplored. In the present study, we provide the first demonstration that HDACi treatment decreases MDSC accumulation in the spleen, blood and tumor bed but increases the proportion of T cells (particularly the frequency of IFN-γ- or perforin-producing CD8+ T cells) in BALB/C mice with 4T1 mammary tumors. In addition, HDACi exposure of bone marrow (BM) cells significantly eliminated the MDSC population induced by GM-CSF or the tumor burden in vitro, which was further demonstrated as functionally important to relieve the inhibitory effect of MDSC-enriched BM cells on T cell proliferation. Mechanistically, HDACi increased the apoptosis of Gr-1+ cells (almost MDSC) compared with that of Gr-1- cells, which was abrogated by the ROS scavenger N-acetylcysteine, suggesting that the HDACi-induced increase in MDSC apoptosis due to increased intracellular ROS might partially account for the observed depletion of MDSC. These findings suggest that the elimination of MDSC using an HDACi may contribute to the overall anti-tumor properties of these agents, highlighting a novel property of HDACi as potent MDSC-targeting agents, which may be used to enhance the efficacy of immunotherapeutic regimens.


Asunto(s)
Inhibidores de Histona Desacetilasas/farmacología , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Células Supresoras de Origen Mieloide/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Neoplasias Mamarias Experimentales/enzimología , Neoplasias Mamarias Experimentales/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células Supresoras de Origen Mieloide/patología
16.
Arch Biochem Biophys ; 608: 34-41, 2016 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-27592306

RESUMEN

Nodal is a member of transforming growth factor beta (TGF-ß) superfamily. Nodal promotes the self-renewal of human cancer stem cells (CSCs) and triggers carcinogenesis of human cancers via an autocrine manner through Smad2/3 pathway. In our study, generation of Nodal-overexpressed cancer cells was constructed, and the effect of Nodal on the stem cell marker Oct-4 was evaluated by overexpression or blocked Nodal/ALKs signaling pathway in non-small cell lung cancer cells A549 and prostate cancer cells PC3. Functionally, Nodal also increased the proliferation via the ß-catenin nuclear translocation. This increase was attributed to GSK-3ß dephosphorylating, and activin receptor-like kinase 4/7 (ALK4/7) played a major role in human cancer cells. Our study provides a positive understanding of Nodal function in cancer cells and suggests a potential novel target for clinical therapeutic research.


Asunto(s)
Transporte Activo de Núcleo Celular , Regulación Neoplásica de la Expresión Génica , Proteína Nodal/metabolismo , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Neoplasias de la Próstata/metabolismo , beta Catenina/metabolismo , Células A549 , Receptores de Activinas Tipo I/metabolismo , Línea Celular Tumoral , Núcleo Celular/metabolismo , Proliferación Celular , Citoplasma/metabolismo , Humanos , Masculino , Transducción de Señal , Transfección
17.
Bioorg Med Chem ; 24(4): 619-26, 2016 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-26740156

RESUMEN

A series of disubstituted xanthones was obtained by cationic modification of xanthone's C2 and C7 with amine groups of different pKa values. Modified structures by using moieties with high pKa values had good antitumor activity according to the MTT assay, AO/EB staining and flow cytometry assay, especially bis-dimethylamine derivative (5a). Further study indicated that compound 5a had good binding activity to telomeric G-quadruplex DNA, as detected by using spectroscopy methods, melting profiles, polymerase chain reaction stop assay and molecular modeling study. The results suggested that the antitumor activity of 5a might be associated with its stabilization of G-quadruplex DNA, which could be developed as new G-quadruplex DNA stabilizer and potent antitumor agents.


Asunto(s)
Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , ADN de Neoplasias/efectos de los fármacos , G-Cuádruplex/efectos de los fármacos , Telómero/efectos de los fármacos , Xantonas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Sitios de Unión/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Citometría de Flujo , Células HeLa , Humanos , Células MCF-7 , Modelos Moleculares , Estructura Molecular , Relación Estructura-Actividad , Xantonas/síntesis química , Xantonas/química
18.
Materials (Basel) ; 17(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38730778

RESUMEN

To enhance the physical and mechanical characteristics of steam-cured concrete, an orthogonal experimental design was utilized to examine the effects of varying contents of fly ash (0 wt%, 10 wt%, 15 wt%, 20 wt%), silica fume (0 wt%, 5 wt%, 10 wt%, 15 wt%), basalt fiber (0 vol%, 0.05 vol%, 0.1 vol%, 0.2 vol%), and polypropylene fiber (0 vol%, 0.05 vol%, 0.1 vol%, 0.2 vol%) on its mechanical properties. Utilizing range and variance analyses, this study identified four preliminary optimized compositions of concrete incorporating fly ash, silica fume, basalt fiber, and polypropylene fiber. On this basis, in order to determine the optimal mix proportion, the mechanical performances, the pore characteristics, and the microstructure of four optimized mix proportions were analyzed. According to the results of macroscopic, fine, and microscopic multi-scale tests, the addition of 15 wt% fly ash, 10 wt% silica ash, 0.2 vol% basalt fiber, and 0.1 vol% polypropylene fiber to the steamed concrete is the best to improve the performance of the steamed concrete. Compared to ordinary concrete, the compressive strength increases by 28%, the tensile strength increases by 40%, and the porosity decreases by 47.2%.

19.
Food Chem ; 445: 138657, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38354640

RESUMEN

Rice varieties of different subspecies types (indica rice and japonica rice) across various geographical origins (Hunan, Jiangsu, and Northeast China) were monitored using microsatellite markers (simple sequence repeats, SSR). 110 representative rice cultivars were collected from the main crop areas. Multiple methods including clustering analysis (neighbor-joining (NJ) method, unweighted pair-group method with arithmetic mean (UPGMA) method), principal component analysis (PCA) and model-based grouping were applied. The study revealed that 25 pairs of SSR markers exhibited a broad range of polymorphism information content (PIC) values, ranging from 0.240 to 0.830. Furthermore, our study successfully achieved a higher overall mean correct rate of 99.09% in determining the geographical origin of rice. Simultaneously, it accurately classified indica rice and japonica rice. These findings are significant as they provide an SSR fingerprint of 110 high-quality rice cultivars, serving as a valuable scientific resource for the detection of rice adulteration and traceability of its origin.


Asunto(s)
Variación Genética , Oryza , Oryza/genética , Polimorfismo Genético , Repeticiones de Microsatélite/genética , Análisis de Componente Principal , Filogenia
20.
ACS Appl Mater Interfaces ; 16(10): 12897-12906, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38412379

RESUMEN

The "von Neumann bottleneck" is a formidable challenge in conventional computing, driving exploration into artificial synapses. Organic semiconductor materials show promise but are hindered by issues such as poor adhesion and a high elastic modulus. Here, we combine polyisoindigo-bithiophene (PIID-2T) with grafted poly(dimethylsiloxane) (PDMS) to synthesize the triblock-conjugated polymer (PIID-2T-PDMS). The polymer exhibited substantial enhancements in adhesion (4.8-68.8 nN) and reductions in elastic modulus (1.6-0.58 GPa) while maintaining the electrical characteristics of PIID-2T. The three-terminal organic synaptic transistor (three-terminal p-type organic artificial synapse (TPOAS)), constructed using PIID-2T-PDMS, exhibits an unprecedented analog switching range of 276×, surpassing previous records, and a remarkable memory on-off ratio of 106. Moreover, the device displays outstanding operational stability, retaining 99.6% of its original current after 1600 write-read events in the air. Notably, TPOAS replicates key biological synaptic behaviors, including paired-pulse facilitation (PPF), short-term plasticity (STP), and long-term plasticity (LTP). Simulations using handwritten digital data sets reveal an impressive recognition accuracy of 91.7%. This study presents a polyisoindigo-bithiophene-based block copolymer that offers enhanced adhesion, reduced elastic modulus, and high-performance artificial synapses, paving the way for the next generation of neuromorphic computing systems.

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