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1.
mSphere ; 9(4): e0018524, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38530018

RESUMO

Most microbial life on Earth is found in localized microenvironments that collectively exert a crucial role in maintaining ecosystem health and influencing global biogeochemical cycles. In many habitats such as biofilms in aquatic systems, bacterial flocs in activated sludge, periphyton mats, or particles sinking in the ocean, these microenvironments experience sporadic or continuous flow. Depending on their microscale structure, pores and channels through the microenvironments permit localized flow that shifts the relative importance of diffusive and advective mass transport. How this flow alters nutrient supply, facilitates waste removal, drives the emergence of different microbial niches, and impacts the overall function of the microenvironments remains unclear. Here, we quantify how pores through microenvironments that permit flow can elevate nutrient supply to the resident bacterial community using a microfluidic experimental system and gain further insights from coupled population-based and computational fluid dynamics simulations. We find that the microscale structure determines the relative contribution of advection vs diffusion, and even a modest flow through a pore in the range of 10 µm s-1 can increase the carrying capacity of a microenvironment by 10%. Recognizing the fundamental role that microbial hotspots play in the Earth system, developing frameworks that predict how their heterogeneous morphology and potential interstitial flows change microbial function and collectively alter global scale fluxes is critical.IMPORTANCEMicrobial life is a key driver of global biogeochemical cycles. Similar to the distribution of humans on Earth, they are often not homogeneously distributed in nature but occur in dense clusters that resemble microbial cities. Within and around these clusters, diffusion is often assumed as the sole mass-transfer process that dictates nutrient supply and waste removal. In many natural and engineered systems such as biofilms in aquatic environments, aggregates in bioremediation, or flocs in wastewater treatment plants, these clusters are exposed to flow that elevates mass transfer, a process that is often overlooked. In this study, we show that advective fluxes can increase the local growth of bacteria in a single microenvironment by up to 50% and shape their metabolism by disrupting localized anoxia or supplying nutrients at different rates. Collectively, advection-enhanced mass transport may thus regulate important biogeochemical transformations in both natural and engineered environments.

2.
Nicotine Tob Res ; 26(4): 427-434, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-37788378

RESUMO

INTRODUCTION: Adolescents are uniquely vulnerable to nicotine addiction, and smoking is common among male adolescents in China. Although China implemented a ban on cigarette and e-cigarette advertising in public places, Chinese youth remain exposed to this marketing, which may contribute to future use. AIMS AND METHODS: From December 2021 to January 2022, we conducted 20 online focus group discussions with 119 adolescents in 10 Chinese cities to explore sources of tobacco marketing exposure, defined as exposure to cigarette and e-cigarette ads and product displays, and what features made marketing attractive. RESULTS: All groups discussed exposure to tobacco ads/displays in public places, including locations near their home or school. Nearly all groups discussed that exposure to online tobacco ads was common, particularly exposure to e-cigarette commercial ads and posts made by classmates or friends selling e-cigarettes. Most groups identified how eye-catching colors, imagery, product packaging, and price promotions featured in e-cigarette ads/displays attracted their attention. CONCLUSIONS: Results suggest Chinese adolescents are exposed to cigarette and e-cigarette ads and displays, many of which are placed in youth-friendly locations and contain youth-appealing features. IMPLICATIONS: Only a handful of studies have examined the influence of cigarette and e-cigarette advertising on youth in the context of China. Prior research has established the relationship between youth exposure to tobacco marketing and increased susceptibility to future use. Our findings emphasize the importance of effectively enforcing and expanding restrictions on cigarette and e-cigarette marketing in order to protect youth from exposure and future smoking/vaping initiation.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Produtos do Tabaco , Vaping , Adolescente , Humanos , Masculino , Publicidade/métodos , China/epidemiologia , Marketing/métodos , Fumar/epidemiologia
3.
J Interferon Cytokine Res ; 41(8): 302-306, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34410877

RESUMO

Psoriasis is a chronic disorder characterized by a complex interplay between keratinocytes and inflammatory mediators. In a previous study, we evaluated diacerein's ability to diminish interleukin (IL)-1's proinflammatory effects on cultured primary human keratinocytes. In this study, we evaluated diacerein's ability to diminish the inflammatory effects of a cytokine mixture (CM) consisting of IL-17A, IL-22, oncostatin M, IL-1A, and tumor necrosis factor (TNF)-alpha on cultured primary human keratinocytes. These five cytokines have been previously shown to induce an in vivo-equivalent cell culture psoriasis model. We also evaluated diacerein's anti-inflammatory effects in comparison to and in combination with infliximab, a TNF-alpha inhibitor currently used in the treatment of psoriasis. We found 81 genes that were significantly (P < 0.05) dysregulated by CM compared to medium control. All three treatment groups (diacerein alone, infliximab alone, and diacerein plus infliximab) diminished the effects of CM on these genes, with the greatest effect seen with diacerein plus infliximab. Using enzyme-linked immunosorbent assay method on cell culture supernatant, we determined the protein concentration for five genes (IL-19, IL-6, CSF3, S100A8, and NAP-2) significantly (P < 0.05) upregulated by CM at the gene level. Diacerein alone diminished the effect of CM on the protein concentration of two genes, whereas diacerein plus infliximab diminished the effect of CM on the protein concentration of all the five genes. Based on these results, we conclude that diacerein alone or in combination with infliximab may have a therapeutic role in psoriasis by downregulating key inflammatory mediators.


Assuntos
Antraquinonas/farmacologia , Mediadores da Inflamação/farmacologia , Infliximab/farmacologia , Queratinócitos/efeitos dos fármacos , Humanos , Interleucina-17/antagonistas & inibidores , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-1alfa/antagonistas & inibidores , Interleucina-1alfa/genética , Interleucina-1alfa/metabolismo , Interleucinas/antagonistas & inibidores , Interleucinas/genética , Interleucinas/metabolismo , Queratinócitos/metabolismo , Oncostatina M/antagonistas & inibidores , Oncostatina M/genética , Oncostatina M/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Interleucina 22
4.
J Exp Psychol Hum Percept Perform ; 47(7): 893-907, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34292047

RESUMO

Individuals are better at recognizing faces from their own ethnic group compared with other ethnicity faces-the other-ethnicity effect (OEE). This finding is said to reflect differences in experience and familiarity to faces from other ethnicities relative to faces corresponding with the viewers' ethnicity. However, own-ethnicity face recognition performance ranges considerably within a population, from very poor to extremely good. In addition, within-population recognition performance on other-ethnicity faces can also vary considerably with some individuals being classed as "other ethnicity face blind" (Wan et al., 2017). Despite evidence for considerable variation in performance within population for faces of both types, it is currently unclear whether the magnitude of the OEE changes as a function of this variability. By recruiting large-scale multinational samples, we investigated the size of the OEE across the full range of own and other ethnicity face performance while considering measures of social contact. We find that the magnitude of the OEE is remarkably consistent across all levels of within-population own- and other-ethnicity face recognition ability, and this pattern was unaffected by social contact measures. These findings suggest that the OEE is a persistent feature of face recognition performance, with consequences for models built around very poor, and very good face recognizers. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Etnicidade , Reconhecimento Facial , Humanos , Individualidade , Reconhecimento Psicológico
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