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1.
iScience ; 25(10): 105156, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36212025

RESUMO

Increasing concentrations of atmospheric CO2 are leading to rising global temperatures and extreme weather events. However, the most prominent method of removing CO2 via direct air capture remains cost-prohibitive. Oceans sequester carbon through several naturally occurring carbon dioxide removal (CDR) processes, one of which includes microorganisms that utilize dissolved inorganic carbon (DIC) in their metabolic processes. Atmospheric CO2 is in dynamic equilibrium with DIC at the ocean's surface. Thus, ocean-based CDR can function to capture carbon from the air indirectly. This work discusses a hybrid method that combines primary CO2 capture via the growth of autotrophic microorganisms (i.e., photosynthetic cyanobacteria) and microbially induced carbonate precipitation. Carbon fixation and carbonate precipitation can be co-optimized using bipolar membrane electrodialysis (BPMED) devices , which generate seawater with an adjustable pH. We examine the scale-up potential for naturally produced bio-carbonate composite material and compare its production with published ocean CDR strategies for reducing anthropogenic CO2 emissions.

2.
J Photochem Photobiol B ; 230: 112427, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35338920

RESUMO

Fewer antibiotics are available for effective management of bacterial infections to date owing to increasing multiple-drug resistance (MDR). Here, we expand our early success in combination of 405 nm blue light irradiation with phenolic compounds to sufficiently kill blue light-refractory MDR Escherichia coli (E. coli). p-Toluquinone (p-TQ) alongside blue light inactivated 7.3 log10E. coli within 6 min, whereas either alone was totally ineffective. A similar killing efficacy was attained with four other pathogens commonly seen in hospital-acquired infections and Enterococcus faecalis (Ef) that don't produce porphyrins-like molecules. The combinatory therapy prevented recurrence of E. coli infection in skin scratch wounds of murine. The bactericidal activity was ascribed to reactive oxygen species (ROS) generation triggered by blue light-mediated excitation of p-TQ, which is less likely to induce resistance because of multi-targeted and non-specific nature of ROS. Remarkably, toxic p-TQ became harmless to mammalian cells after brief exposure to blue light while retaining its bactericidal activity. The opposite effect of blue light on p-TQ activity unravels a novel, simple strategy to detoxify p-TQ and its combination with blue light as a safe and efficacious bactericidal modality for managing MDR bacterial infections.


Assuntos
Infecções Bacterianas , Escherichia coli , Animais , Antibacterianos/farmacologia , Benzoquinonas , Luz , Mamíferos , Camundongos , Espécies Reativas de Oxigênio/farmacologia
3.
ACS Appl Mater Interfaces ; 14(14): 16505-16514, 2022 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-35353487

RESUMO

In this work, we demonstrate an experimental realization of a granular multiferroic composite, where the magnetic state of a nanocrystal array is modified by tuning the interparticle exchange coupling using an applied electric field. Previous theoretical models of a granular multiferroic composite predicted a unique magnetoelectric coupling mechanism, in which the magnetic spins of the ensemble are governed by interparticle exchange. The extent of these exchange interactions can be controlled by varying the local dielectric environment between grains. We specifically utilize the strong dielectric dependence of ferroelectric materials to modify the interparticle coupling of closely spaced magnetic nanoparticles using either a change in temperature or an electric field. This coupling modifies the ensemble magnetic coercivity and thus the superparamagnetic-to-ferromagnetic phase transition temperature. Through the use of two different ferroelectrics, our results suggest that this magnetoelectric coupling mechanism could be generalized as a new class of multiferroic material, applicable to a broad range of ferroelectric/magnetic nanocrystal composites.

4.
Cancers (Basel) ; 13(17)2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34503214

RESUMO

The etiology of colorectal cancer (CRC) is complex. Approximately, 10% of individuals with CRC have predisposing germline mutations that lead to familial cancer syndromes, whereas most CRC patients have sporadic cancer resulting from a combination of environmental and genetic risk factors. It has become increasingly clear that chronic alcohol consumption is associated with the development of sporadic CRC; however, the exact mechanisms by which alcohol contributes to colorectal carcinogenesis are largely unknown. Several proposed mechanisms from studies in CRC models suggest that alcohol metabolites and/or enzymes associated with alcohol metabolism alter cellular redox balance, cause DNA damage, and epigenetic dysregulation. In addition, alcohol metabolites can cause a dysbiotic colorectal microbiome and intestinal permeability, resulting in bacterial translocation, inflammation, and immunosuppression. All of these effects can increase the risk of developing CRC. This review aims to outline some of the most significant and recent findings on the mechanisms of alcohol in colorectal carcinogenesis. We examine the effect of alcohol on the generation of reactive oxygen species, the development of genotoxic stress, modulation of one-carbon metabolism, disruption of the microbiome, and immunosuppression.

5.
Sci Transl Med ; 13(575)2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33408183

RESUMO

Development of alternatives to antibiotics is one of the top priorities in the battle against multidrug-resistant (MDR) bacterial infections. Here, we report that two naturally occurring nonantibiotic modalities, blue light and phytochemical carvacrol, synergistically kill an array of bacteria including their planktonic forms, mature biofilms, and persisters, irrespective of their antibiotic susceptibility. Combination but not single treatment completely or substantially cured acute and established biofilm-associated Acinetobacter baumannii and methicillin-resistant Staphylococcus aureus infections of full thickness murine third-degree burn wounds and rescued mice from lethal Pseudomonas aeruginosa skin wound infections. The combined therapy diminished bacterial colony-forming units as high as 7.5 log10 within 30 min and introduced few adverse events in the survival of cocultured mammalian cells, wound healing, or host DNA. Mechanistic studies revealed that carvacrol was photocatalytically oxidized into a series of photoreactive substrates that underwent photolysis or additional photosensitization reactions in response to the same blue light, forming two autoxidation cycles that interacted with each other resulting in robust generation of cytotoxic reactive oxygen species. This phototoxic reaction took place exclusively in bacteria, initiated by blue light excitation of endogenous porphyrin-like molecules abundantly produced in bacteria compared with mammalian cells. Moreover, no bacterial resistance developed to the combined treatment after 20 successive passages. This highly selective phototoxic reaction confers a unique strategy to combat the growing threat of MDR bacteria.


Assuntos
Acinetobacter baumannii , Staphylococcus aureus Resistente à Meticilina , Animais , Antibacterianos/uso terapêutico , Bactérias , Biofilmes , Cimenos , Camundongos , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos , Pseudomonas aeruginosa
6.
J Med Internet Res ; 22(8): e17449, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32780027

RESUMO

BACKGROUND: Novel alcohol prevention strategies are needed for heavy-drinking young adults. Sleep problems are common among young adults who drink heavily and are a risk factor for developing an alcohol use disorder (AUD). Young adults, interested in the connection between sleep and alcohol, are open to getting help with their sleep. Therefore, sleep interventions may offer an innovative solution. This study evaluates social media advertising for reaching young adults and recruiting them for a new alcohol prevention program focused on sleep. OBJECTIVE: This study aims to evaluate the effectiveness and cost of using Facebook, Instagram, and Snapchat advertising to reach young adults who drink heavily for a sleep intervention; characterize responders' sleep, alcohol use, and related concerns and interests; and identify the most appealing advertising content. METHODS: In study 1, advertisements targeting young adults with sleep concerns, heavy alcohol use, or interest in participating in a sleep program ran over 3 months. Advertisements directed volunteers to a brief web-based survey to determine initial sleep program eligibility and characterize the concerns or interests that attracted them to click the advertisement. In study 2, three advertisements ran simultaneously for 2 days to enable us to compare the effectiveness of specific advertising themes. RESULTS: In study 1, advertisements generated 13,638 clicks, 909 surveys, and 27 enrolled volunteers in 3 months across the social media platforms. Fees averaged US $0.27 per click, US $3.99 per completed survey, US $11.43 per volunteer meeting initial screening eligibility, and US $106.59 per study enrollee. On average, those who completed the web-based survey were 21.1 (SD 2.3) years of age, and 69.4% (631/909) were female. Most reported sleep concerns (725/909, 79.8%) and an interest in the connection between sleep and alcohol use (547/909, 60.2%), but few had drinking concerns (49/909, 5.4%). About one-third (317/909, 34.9%) were identified as being at risk for developing an AUD based on a validated alcohol screener. Among this subsample, 8.5% (27/317) met the final criteria and were enrolled in the trial. Some volunteers also referred additional volunteers by word of mouth. In study 2, advertisements targeting sleep yielded a higher response rate than advertisements targeting alcohol use (0.91% vs 0.56% click rate, respectively; P<.001). CONCLUSIONS: Social media advertisements designed to target young adults with sleep concerns reached those who also drank alcohol heavily, despite few being concerned about their drinking. Moreover, advertisements focused on sleep were more effective than those focused on drinking. Compared with previous studies, cost-effectiveness was moderate for engagement (impressions to clicks), excellent for conversion (clicks to survey completion), and reasonable for enrollment. These data demonstrate the utility of social media advertising focused on sleep to reach young adults who drink heavily and recruit them for intervention.


Assuntos
Consumo de Bebidas Alcoólicas/prevenção & controle , Alcoolismo/terapia , Transtornos do Sono-Vigília/etiologia , Mídias Sociais/normas , Adolescente , Adulto , Feminino , Humanos , Masculino , Estudos Prospectivos , Inquéritos e Questionários , Voluntários , Adulto Jovem
7.
Sci Total Environ ; 690: 853-866, 2019 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-31302550

RESUMO

1,4-Dioxane has historically been used to stabilize chlorinated solvents and more recently has been found as a contaminant of numerous consumer and food products. Once discharged into the environment, its physical and chemical characteristics facilitate migration in groundwater, resulting in widespread contamination of drinking water supplies. Over one-fifth of U.S. public drinking water supplies contain detectable levels of 1,4-dioxane. Remediation efforts using common adsorption and membrane filtration techniques have been ineffective, highlighting the need for alternative removal approaches. While the data evaluating human exposure and health effects are limited, animal studies have shown chronic exposure to cause carcinogenic responses in the liver across multiple species and routes of exposure. Based on this experimental evidence, the U.S. Environmental Protection Agency has listed 1,4-dioxane as a high priority chemical and classified it as a probable human carcinogen. Despite these health concerns, there are no federal or state maximum contaminant levels for 1,4-dioxane. Effective public health policy for this emerging contaminant requires additional information about human health effects, chemical interactions, environmental fate, analytical detection, and treatment technologies. This review highlights the current state of knowledge, key uncertainties, and data needs for future research on 1,4-dioxane.

8.
Anim Sci J ; 90(6): 781-789, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30938015

RESUMO

Skeletal muscle fiber is largely classified into two types: type 1 (slow-twitch) and type 2 (fast-twitch) fibers. Meat quality and composition of fiber types are thought to be closely related. Previous research showed that overexpression of constitutively active peroxisome proliferator-activated receptor (PPAR)δ, a nuclear receptor present in skeletal muscle, increased type 1 fibers in mice. In this study, we found that hexane extracts of Yamabushitake mushroom (Hericium erinaceus) showed PPARδ agonistic activity in vitro. Eight-week-old C57BL/6J mice were fed a diet supplemented with 5% (w/w) freeze-dried Yamabushitake mushroom for 24 hr. After the treatment period, the extensor digitorum longus (EDL) muscles were excised. The Yamabushitake-supplemented diet up-regulated the PPARδ target genes Pdk4 and Ucp3 in mouse skeletal muscles in vivo. Furthermore, feeding the Yamabushitake-supplemented diet to mice for 8 weeks resulted in a significant increase in muscle endurance. These results indicate that Yamabushitake mushroom contains PPARδ agonistic ligands and that dietary intake of Yamabushitake mushroom could activate PPARδ in skeletal muscle of mice. Unexpectedly, we observed no significant alterations in composition of muscle fiber types between the mice fed control and Yamabushitake-supplemented diets.


Assuntos
Agaricales/química , Suplementos Nutricionais , Força Muscular , Músculo Esquelético/metabolismo , PPAR delta/agonistas , Extratos Vegetais/farmacologia , Animais , Hexanos , Ligantes , Masculino , Camundongos Endogâmicos C57BL , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , PPAR delta/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Desidrogenase Quinase de Transferência de Acetil , Fatores de Tempo , Proteína Desacopladora 3/genética , Proteína Desacopladora 3/metabolismo , Regulação para Cima/efeitos dos fármacos
9.
Lab Invest ; 98(6): 783-798, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29463877

RESUMO

The bark of Cinnamomum cassia (C. cassia) has been used for the management of coronary heart disease (CHD) and diabetes mellitus. C. cassia may target the vasculature, as it stimulates angiogenesis, promotes blood circulation and wound healing. However, the active components and working mechanisms of C. cassia are not fully elucidated. The Shexiang Baoxin pill (SBP), which consists of seven medicinal materials, including C. cassia etc., is widely used as a traditional Chinese patent medicine for the treatment of CHD. Here, 22 single effective components of SBP were evaluated against the human umbilical vein endothelial cells (HUVECs). We demonstrated that in HUVECs, cinnamaldehyde (CA) stimulated proliferation, migration, and tube formation. CA also activated the phosphatidylinositol 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways. Furthermore, the secretion of vascular endothelial growth factor (VEGF) from HUVECs was increased by CA. In vivo, CA partially restored intersegmental vessels in zebrafish pretreated with PTK787, which is a selective inhibitor for vascular endothelial growth factor receptor (VEGFR). CA also showed pro-angiogenic efficacy in the Matrigel plug assay. Additionally, CA attenuated wound sizes in a cutaneous wound model, and elevated VEGF protein and CD31-positive vascular density at the margin of these wounds. These results illustrate that CA accelerates wound healing by inducing angiogenesis in the wound area. The potential mechanism involves activation of the PI3K/AKT and MAPK signaling pathways. Such a small non-peptide molecule may have clinical applications for promoting therapeutic angiogenesis in chronic diabetic wounds and myocardial infarction.


Assuntos
Acroleína/análogos & derivados , Sistema de Sinalização das MAP Quinases/fisiologia , Neovascularização Fisiológica/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/fisiologia , Cicatrização/efeitos dos fármacos , Acroleína/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Óxido Nítrico Sintase Tipo III/fisiologia , Ftalazinas/farmacologia , Piridinas/farmacologia , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular/biossíntese , Peixe-Zebra
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