Using Holographic Microscopy To Measure the Effect of Confinement on Crowding Agents in Lipid Vesicles.

The hydrodynamic effects of macromolecular crowding inside cells are often studied in vitro by using polymers as crowding agents. Confinement of polymers inside cell-sized droplets has been shown to affect the diffusion of small molecules. Here we develop a method, based on digital holographic microscopy, to measure the diffusion of polystyrene microspheres that are confined within lipid vesicles containing a high concentration of solute. We apply the method to three solutes of varying complexity: sucrose, dextran, and PEG, prepared at ∼7 % (w/w). We find that diffusion inside and outside the vesicles is the same when the solute is sucrose or dextran that is prepared below the critical overlap concentration. For poly(ethylene glycol), which is present at a concentration higher than the critical overlap concentration, the diffusion of microspheres inside vesicles is slower, hinting at the potential effects of confinement on crowding agents.

A cross-sectional survey of prevalence and correlates of sunscreen use among a rural Tri-State Appalachian population.

Over five million people are diagnosed with skin cancers each year. With the sun's ultraviolet radiation exposure being the major risk factor for all skin cancers, sunscreen use is a vital preventative measure. However, in the US, sunscreen use remains inadequate. Furthermore, research regarding sunscreen use amongst rural populations has been particularly sparse. To identify the prevalence of sunscreen use and identify correlates thereof, a cross-sectional study was conducted on a sample of patients from rural Tri-State Appalachia. A total of 212 patients participated in this study. Findings showed that young individuals, females and those with higher educational attainment were more likely to utilize sunscreen. Furthermore, individuals with skin types prone to burning were four times as likely to utilize sunscreen. Overall, sunscreen use amongst residents in the Tri-State area was low, emphasizing the need for targeted interventions to prevent the incidence of skin cancer amongst this population.

Distance and Microsphere Aggregation-Based DNA Detection in a Paper-Based Microfluidic Device.

In paper-based microfluidics, the simplest devices are colorimetric, giving qualitative results. However, getting quantitative data can be quite a bit more difficult. Distance-based devices provide a user-friendly means of obtaining quantitative data without the need for any additional equipment, simply by using an included ruler or calibrated markings. This article details the development of a quantitative DNA detection device that utilizes the aggregation of polystyrene microspheres to affect the distance that microspheres wick through filter paper. The microspheres are conjugated to single-stranded DNA (ssDNA) oligomers that are partially complementary to a target strand and, in the presence of the target strand, form a three-strand complex, resulting in the formation of aggregates. The higher the concentration of the target strand, the larger the aggregate, and the shorter the distance wicked by the microspheres. This behavior was investigated across a wide range of target concentrations and under different incubation times to understand aggregate formation. The device was then used to successfully detect a target strand spiked in extracted plant DNA.

Skin Cancer Knowledge, Attitudes, and Practices among Chinese Population: A Narrative Review.

Skin cancers are becoming a substantial public health problem in China. Fair skin and increased exposure to ultraviolet B (UVB) rays from the sun are among the most substantial risk factors for skin cancer development, thus making the Chinese people vulnerable to this group of diseases. The purpose of this article is to present a narrative review of the knowledge, attitudes, and practices (KAP) related to skin cancers within the Chinese population. A systematic electronic search of MEDLINE (PubMed), CINAHL, ScienceDirect, and Google Scholar databases yielded nine articles that met the inclusion criteria. The review found that although sunscreen application was a commonly used method of skin protection among the general Chinese population, educational interventions enhancing current knowledge and attitudes about the effects of UVB rays on skin from undue sun exposure were limited in many smaller communities of the country. Hence, there is an essential need to design effective, evidence-based educational programs promoting sun protection behaviors in both congregated and sparsely populated areas of China.