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1.
Circ Res ; 132(9): 1168-1180, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-37104558

RESUMO

The use of electronic nicotine delivery systems, specifically electronic cigarettes (e-cig), has risen dramatically within the last few years; the demographic purchasing these devices is now predominantly adolescents that are not trying to quit the use of traditional combustible cigarettes, but rather are new users. The composition and appearance of these devices has changed since their first entry into the market in the late 2000s, but they remain composed of a battery and aerosol delivery system that is used to deliver breakdown products of propylene glycol/vegetable glycerin, flavorings, and potentially nicotine or other additives. Manufacturers have also adjusted the type of nicotine that is used within the liquid to make the inhalation more palatable for younger users, further affecting the number of youth who use these devices. Although the full spectrum of cardiovascular and cardiometabolic consequences of e-cig use is not fully appreciated, data is beginning to show that e-cigs can cause both short- and long-term issues on cardiac function, vascular integrity and cardiometabolic issues. This review will provide an overview of the cardiovascular, cardiometabolic, and vascular implications of the use of e-cigs, and the potential short- and long-term health effects. A robust understanding of these effects is important in order to inform policy makers on the dangers of e-cigs use.


Assuntos
Doenças Cardiovasculares , Sistemas Eletrônicos de Liberação de Nicotina , Vaping , Humanos , Adolescente , Nicotina/efeitos adversos , Pulmão/metabolismo , Vaping/efeitos adversos , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/metabolismo
3.
Circulation ; 145(3): 219-232, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35041473

RESUMO

Electronic cigarettes (e-cigarettes) are battery powered electronic nicotine delivery systems that use a propylene glycol/vegetable glycerin base to deliver vaporized nicotine and flavorings to the body. E-cigarettes became commercially available without evidence regarding their risks, long-term safety, or utility in smoking cessation. Recent clinical trials suggest that e-cigarette use with counseling may be effective in reducing cigarette use but not nicotine dependence. However, meta-analyses of observational studies demonstrate that e-cigarette use is not associated with smoking cessation. Cardiovascular studies reported sympathetic activation, vascular stiffening, and endothelial dysfunction, which are associated with adverse cardiovascular events. The majority of pulmonary clinical trials in e-cigarette users included standard spirometry as the primary outcome measure, reporting no change in lung function. However, studies reported increased biomarkers of pulmonary disease in e-cigarette users. These studies were conducted in adults, but >30% of high school-age adolescents reported e-cigarette use. The effects of e-cigarette use on cardiopulmonary endpoints in adolescents and young adults remain unstudied. Because of adverse clinical findings and associations between e-cigarette use and increased incidence of respiratory diseases in people who have never smoked, large longitudinal studies are needed to understand the risk profile of e-cigarettes. Consistent with the Centers for Disease Control and Prevention recommendations, clinicians should monitor the health risks of e-cigarette use, discourage nonsmokers and adolescents from using e-cigarettes, and discourage smokers from engaging in dual use without cigarette reduction or cessation.


Assuntos
Fumar Cigarros/efeitos adversos , Sistemas Eletrônicos de Liberação de Nicotina , Papel do Médico , Vaping/efeitos adversos , Humanos , Fumar/epidemiologia , Tabagismo/prevenção & controle
4.
Life Sci ; 289: 120147, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34785191

RESUMO

Exposure to dust, smoke, and fumes containing volatile chemicals and particulate matter (PM) from the World Trade Center (WTC) towers' collapse impacted thousands of citizens and first responders (FR; firefighters, medicals staff, police officers) of New York City. Surviving FR and recovery workers are increasingly prone to age-related diseases that their prior WTC dust exposures might expedite or make worse. This review provides an overview of published WTC studies concerning FR/recovery workers' exposure and causal mechanisms of age-related disease susceptibility, specifically those involving the cardiopulmonary and neurological systems. This review also highlights the recent findings of the major health effects of cardiovascular, pulmonary, and neurological health sequelae from WTC dust exposure. To better treat those that risked their lives during and after the disaster of September 11, 2001, the deleterious mechanisms that WTC dust exposure exerted and continue to exert on the heart, lungs, and brain of FR must be better understood.


Assuntos
Doenças Cardiovasculares , Pneumopatias , Doenças do Sistema Nervoso , Material Particulado/toxicidade , Ataques Terroristas de 11 de Setembro , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Humanos , Pneumopatias/induzido quimicamente , Pneumopatias/epidemiologia , Doenças do Sistema Nervoso/induzido quimicamente , Doenças do Sistema Nervoso/epidemiologia , Cidade de Nova Iorque/epidemiologia
5.
MethodsX ; 8: 101433, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34226865

RESUMO

Precautionary measures of physical isolation, social distancing, and masks have all aided in controlling the spread of COVID-19. However, detection of the virus is crucial to implement isolation of infected individuals. This paper presents the innovative repurposing of lab materials, workspace, and personnel in response to the COVID-19-induced shutdown and consequential shortage of commercially made virus transport media (VTM). This method for VTM production highlights the ability of standard research labs to fulfill the needs of those affected by the pandemic and potential recurrence of outbreaks. Further, the collaboration of the various entities at The Ohio State University Wexner Medical Center (OSUWMC) allowed for efficient production and distribution of VTM tubes to facilitate mass COVID-19 testing. We propose that implementation of this process by university research labs would enable quicker interventions, potentially better outcomes, and prevention of further spread of disease.

6.
J Chem Phys ; 154(16): 164902, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33940801

RESUMO

Fluorescence correlation spectroscopy was used to show that the temperature-dependent diffusion coefficient of poly(ethylene oxide) (PEO) adsorbed on polystyrene and different poly(alkyl methacrylate) (PAMA) films in aqueous solution exhibited a maximum close to (but below) the surface glass transition temperature, Tgs, of the film. This elevated diffusion was observed over a small range of temperatures below Tgs for these surfaces, and at other temperatures, the diffusion was similar to that on silicon, although the diffusion coefficient for PEO on polystyrene at temperatures above Tgs did not completely decrease to that on silicon, in contrast to the PAMA surfaces. It is concluded that the enhanced surface mobility of the films near the surface glass transition temperature induces conformational changes in the adsorbed PEO. The origin of this narrow and dramatic increase in diffusion coefficient is not clear, but it is proposed that it is caused by a coupling of a dominant capillary mode in the liquid surface layer with the polymer. Friction force microscopy experiments also demonstrate an unexpected increase in friction at the same temperature as the increase in diffusion coefficient.

7.
Macromolecules ; 51(16): 6312-6317, 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30174342

RESUMO

The diffusion of rhodamine-labeled poly(ethylene glycol) (r-PEG) within surface-grafted poly(ethylene glycol) (s-PEG) layers in aqueous solution at 18 °C was measured by fluorescence correlation spectroscopy. The diffusion coefficient of r-PEG within s-PEG was controlled by the grafting density, σ, and scaled as σ-1.42±0.09. It is proposed that a characteristic blob size associated with the grafted (brush) layer defines the region through which the r-PEG diffusion occurs. The diffusion coefficients for r-PEG in semidilute solution were found to be similar to those in the brushes.

8.
Biochim Biophys Acta ; 1848(2): 518-26, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25462171

RESUMO

The mechanical properties of Rhodococcus RC291 were measured using force spectroscopy equipped with a bacterial cell probe. Rhodococcal cells in the late growth stage of development were found to have greater adhesion to a silicon oxide surface than those in the early growth stage. This is because there are more extracellular polymeric substances (EPS) that contain nonspecific binding sites available on the cells of late growth stage. It is found that EPS in the late exponential phase are less densely bound but consist of chains able to extend further into their local environment, while the denser EPS at the late stationary phase act more to sheath the cell. Contraction and extension of the EPS could change the density of the binding sites, and therefore affect the magnitude of the adhesion force between the EPS and the silicon oxide surface. By treating rhodococcal EPS as a surface-grafted polyelectrolyte layer and using scaling theory, the interaction between EPS and a solid substrate was modelled for the cell approaching the surface which revealed that EPS possess a large capacity to store charge. Changing the pH of the surrounding medium acts to change the conformation of EPS chains.


Assuntos
Polissacarídeos Bacterianos/química , Rhodococcus/química , Dióxido de Silício/química , Aderência Bacteriana , Sítios de Ligação , Concentração de Íons de Hidrogênio , Microscopia de Força Atômica , Conformação Molecular , Sondas Moleculares/química , Polilisina/química , Eletricidade Estática , Propriedades de Superfície
9.
Theriogenology ; 81(5): 764-9, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24423988

RESUMO

The curvilinear velocity (VCL) of boar spermatozoa between standard microscopy glassware decreases when the slides are coated with the hydrophobic polymer polystyrene (PS) compared with the less hydrophobic poly(methyl methacrylate) (PMMA) coating. Sperm from three boars were observed and analyzed using particle tracking software. The VCL did not differ significantly between coatings of different thickness, indicating no penetration of the sperm into the coating and that only the surface layer of the polymer film interacts with the sperm and buffer medium. The VCL of sperm between PS-coated surfaces was significantly reduced compared with PMMA surfaces (P < 0.0001), and this was attributed to a stronger hydrophobic effect between PS and water. The size of this effect varied between different boars, perhaps as a consequence of variations in hydrophobicity of sperm from different boars or different ejaculates. The modification of surface properties in this way may improve our understanding of sperm behavior and may provide improvements to assisted conception techniques as animal or human sperm used in assisted conception are frequently manipulated in laboratory plastics as part of diagnostic procedures (e.g., semen analysis) or before injection into an oocyte or during the co-incubation with the oocyte in IVF. Controlling the velocity of sperm using the interaction properties of inert polymer coatings could lead to new sperm selection procedures for clinical use or the development of model systems to better understand sperm-surface interactions.


Assuntos
Interações Hidrofóbicas e Hidrofílicas , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/química , Propriedades de Superfície , Suínos , Animais , Masculino , Plásticos , Polimetil Metacrilato/química , Poliestirenos/química , Análise do Sêmen , Água/química
10.
Macromol Rapid Commun ; 32(18): 1411-8, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21751276

RESUMO

We consider the behaviour of single molecules on surfaces and, more generally, in confined environments. These are loosely split into three sections: single molecules in biology, the physics of single molecules on surfaces and controlled (directed) diffusion. With recent advances in single molecule detection techniques, the importance and mechanisms of single molecule processes such as localised enzyme production and intracellular diffusion across membranes has been highlighted, emphasising the extra information that cannot be obtained with techniques that present average behaviour. Progress has also been made in producing artificial systems that can control the rate and direction of diffusion, and because these are still in their infancy (especially in comparison to complex biological systems), we discuss the new physics revealed by these phenomena.


Assuntos
Substâncias Macromoleculares/química , Proteínas/química , Animais , Difusão , Humanos , Modelos Biológicos
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