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We report here a new DNA detection method in which polymer growth in atom transfer radical polymerization (ATRP) is used as a means to amplify detection signals. In this method, DNA hybridization and ligation reactions led to the attachment of ATRP initiators on a solid surface where specific DNA sequences were located. These initiators subsequently triggered the growth of poly(hydroxyethyl methacrylate) (PHEMA) at the end of immobilized DNA molecules and formed polymer brushes. The formation of PHEMA altered substrate opacity, rendering the corresponding spots readily distinguishable to the naked eye. A second ATRP reaction to form branched polymers on the surface drastically improved the visibility of DNA hybridization and significantly shortened the detection time. The resulting polymer film was characterized using infrared spectroscopy, ellipsometry, contact angle measurements, and atomic force microscopy. Direct visualization of 1 fmol of target DNA molecules of interest was demonstrated. A proof-of-principle experiment to detect DNA point mutation was conducted. The perfectly matched DNA targets were distinctively differentiated from those with mutations. The demonstrated capability to detect DNA mutation with direct visualization laid the groundwork for the future development of detector-free testing kits in single-nucleotide polymorphism screenings.

Young, Black, gay bisexual or other MSM are significantly less likely to use PrEP than their White counterparts. These disparities may be due, in part, to medical mistrust and mistreatment within the healthcare system. This study aimed to uncover how young Black MSM's perceptions of, and experiences with, health care contribute to low engagement in the healthcare system and low PrEP utilization. In late 2017 and early 2018, we conducted six focus groups with 44 Black MSM ages 16-25 in Milwaukee. Focus group topics included participants' knowledge and perceptions of PrEP, perceptions and stereotypes about PrEP users, and general healthcare utilization patterns and behaviors. Focus group transcripts were transcribed verbatim and coded using MAXQDA qualitative analysis software. We used a team-based approach to thematic content analysis to understand how racism and homonegativity affected healthcare access and experiences. Results from this study help to characterize what contributes to mistrust of the healthcare system and healthcare providers to negatively affect PrEP use among young Black MSM. Focus group discussions revealed how previous and anticipated negative interactions with physicians and skepticism about the healthcare system have alienated young Black MSM from the health care system and created significant barriers to PrEP. Efforts to increase PrEP uptake and must address negative and discriminatory interactions with providers and the healthcare system.

Cognitive impairment is prevalent in patients presenting for CABG surgery. Impaired cognition before surgery must be considered when assessing the effects of CABG surgery on cognitive performance.

Drug induced cognitive change is generally investigated using small sample sizes. In terms of null hypothesis significance testing (NHST) this can render a meaningful change non-significant, as a result of insufficient power in the statistical model. NHST leads to 'all or none' thinking, where a non-significant result is interpreted as an absence of change. An effect size calculation indicates the magnitude of change which has occurred post-intervention, and therefore whether a significant result is meaningful. We used a scopolamine challenge to demonstrate the usefulness of effect sizes. The aim of the study was to determine how effect sizes could describe the cognitive changes that occur following administration of subcutaneous scopolamine (s.c. scopolamine). Twenty four healthy young males (M = 32.6, sd = 4.5 years) were administered placebo and 0.2 mg, 0.4 mg & 0.6 mg of s.c. scopolamine using a 4-way crossover design. Memory, learning, psychomotor function, attention and executive function were assessed. Scopolamine significantly impaired performance on all tasks in a dose and time related manner. These results demonstrate the functionality of change scores to draw comparisons between different times and doses. This methodology overcomes the limitations of comparisons between studies using different tasks, doses and time at which cognitive functions are measured.

Computerized tests are suitable for measuring cognitive change after CABG surgery and may detect change in a greater proportion of patients 6 days after CABG surgery than conventional neuropsychological tests.

High-dose fentanyl is not associated with a difference in the incidence of POCD at 3 or 12 months after surgery. Low-dose fentanyl leads to shorter postoperative ventilation times and may be associated with a greater incidence of POCD 1 week after surgery. Early POCD is associated with an increased duration of stay in the hospital.

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