Dark-adapted red flash ERGs in healthy adults

Purpose

The x-wave of the dark-adapted (DA) ERG to a red flash reflects DA cone function. This exploratory study of healthy adults aimed to investigate changes in the DA red ERG with flash strength and during dark adaptation to optimise visualisation and therefore quantification of the x-wave.

Methods

The effect of altering red flash strength was investigated in four subjects by recording ERGs after 20 min dark adaptation to red flashes (0.2–2.0 cd s m⁻²) using skin electrodes and natural pupils. The effect of dark adaptation duration was investigated in 16 subjects during 20 min in the dark, by recording DA 1.5 red ERGs at 1, 2, 3, 4, 5, 10, 15 and 20 min.

Results

For a dark adaption period of 20 min, the x-wave was more clearly visualised to weaker (< 0.6 cd s m⁻²) red flash strengths: to stronger flashes it became obscured by the b-wave. For red flashes of 1.5 cd s m⁻², the x-wave was most prominent in ERGs recorded after 1–5 min of dark adaptation: with longer dark adaptation, it was subsumed into the b-wave’s rising edge.

Conclusions

This small study suggests that x-wave visibility in healthy subjects after 20 min dark adaptation is improved by using flashes weaker than around 0.6 cd s m⁻²; for flash strengths of 1.5 cd s m⁻², x-wave visibility is enhanced by recording after only around 5 min of dark adaptation. No evidence was found that interim red flash ERGs affect the dark-adapted state of the normal retina.

Low intensity transcranial electric stimulation: Safety, ethical, legal regulatory and application guidelines

Low intensity transcranial electrical stimulation (TES) in humans, encompassing transcranial direct current (tDCS), transcutaneous spinal Direct Current Stimulation (tsDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation or their combinations, appears to be safe. No serious adverse events (SAEs) have been reported so far in over 18,000 sessions administered to healthy subjects, neurological and psychiatric patients, as summarized here. Moderate adverse events (AEs), as defined by the necessity to intervene, are rare, and include skin burns with tDCS due to suboptimal electrode-skin contact. Very rarely mania or hypomania was induced in patients with depression (11 documented cases), yet a causal relationship is difficult to prove because of the low incidence rate and limited numbers of subjects in controlled trials. Mild AEs (MAEs) include headache and fatigue following stimulation as well as prickling and burning sensations occurring during tDCS at peak-to-baseline intensities of 1-2mA and during tACS at higher peak-to-peak intensities above 2mA. The prevalence of published AEs is different in studies specifically assessing AEs vs. those not assessing them, being higher in the former. AEs are frequently reported by individuals receiving placebo stimulation. The profile of AEs in terms of frequency, magnitude and type is comparable in healthy and clinical populations, and this is also the case for more vulnerable populations, such as children, elderly persons, or pregnant women. Combined interventions (e.g., co-application of drugs, electrophysiological measurements, neuroimaging) were not associated with further safety issues. Safety is established for low-intensity 'conventional' TES defined as <4mA, up to 60min duration per day. Animal studies and modeling evidence indicate that brain injury could occur at predicted current densities in the brain of 6.3-13A/m2 that are over an order of magnitude above those produced by tDCS in humans. Using AC stimulation fewer AEs were reported compared to DC. In specific paradigms with amplitudes of up to 10mA, frequencies in the kHz range appear to be safe. In this paper we provide structured interviews and recommend their use in future controlled studies, in particular when trying to extend the parameters applied. We also discuss recent regulatory issues, reporting practices and ethical issues. These recommendations achieved consensus in a meeting, which took place in Göttingen, Germany, on September 6-7, 2016 and were refined thereafter by email correspondence.

Assessing the Efficacy of a Group Mediated Nutritional Knowledge Intervention for Individuals with Obesity

Purpose: This study reports on the effect of a group-based nutrition and physical activity intervention program on nutrition knowledge and eating habits in a cohort of people with obesity.

Methods: A quasi-experimental design with pre- and post-test measures. The intervention consisted of physical activity led by certified exercise physiologists and a nutritional education component led by registered dietitians over a 6-month period followed by 6 months of self-management. Participants’ nutrition knowledge and eating habits were assessed using the modified Nutrition Assessment, the Nutrition Knowledge Survey, and the Food Choice Questionnaires at baseline, after the 6-month intervention, and after 6 months of self-management.

Results: Complete data were available for 59 (40%) of participants after 12 months because of attrition. Nutritional knowledge and behaviours improved. Participants reported increasing their consumption of healthy foods during the active intervention and maintained these changes through the self-management phase. Knowledge of healthy foods was improved and a greater likelihood of choosing food for weight control and health properties was reported.

Conclusions: Knowledge and reported consumption of healthier nutrition improved during the active intervention and was maintained during the self-management period for individuals who completed the program. Registered dietitians can play an important role in managing patients with obesity in group settings.

Oxidative damage to myelin proteins accompanies peripheral nerve motor dysfunction in aging C57BL/6 male mice

Aging is associated with a decline in peripheral nerve function of both motor and sensory nerves. The decline in function of peripheral sensorimotor nerves with aging has been linked to sarcopenia, the age-related decline in muscle mass and function that significantly compromises the quality of life in older humans. In this study, we report a significant increase in oxidized fatty acids and insoluble protein carbonyls in sciatic nerves of aged C57BL/6 male mice (28-30mo) that exhibit a profound decline in motor nerve function and degenerative changes in both axon and myelin structure, compared to young mice (6-8mo). Our data further suggests that this age-related loss of function of peripheral motor nerves is likely precipitated by changes in mechanisms that protect and/or repair oxidative damage. We predict that interventions that target these mechanisms may protect against age-related decline in peripheral sensorimotor nerve function and likely improve the debilitating outcome of sarcopenia in older humans.

Composing hope through collage: A community-based intervention for cancer survivors living with lymphedema

Secondary lymphedema after cancer may result in distress, yet few interventions exist to support coping skills in this population. As part of a community-based intervention, we piloted the use of creative practices to promote active orientations to hope. A total of 19 participants completed the workshops; 11 collaged. The main themes address the collage processes as well as their content. The former addresses sub-themes such as selecting/composing. The latter includes sub-themes related to movement depicted in the collages. Collages and their associated discussions concretized hoping as an active and accessible process for participants living with two chronic illnesses.

Clinical Characteristics and Outcomes of Late Relapse in Stage I Testicular Seminoma

AIMS

To identify the characteristics and outcomes associated with late relapse in stage I seminoma.

MATERIALS AND METHODS

A retrospective review was carried out of all patients with stage I seminoma managed at our institution between 1981 and 2011. Data were obtained from a prospectively maintained database. Late relapse was defined as tumour recurrence > 2 years after orchiectomy.

RESULTS

Overall, 1060 stage I seminoma patients were managed with active surveillance (n=766) or adjuvant radiotherapy (n=294). At a median follow-up of 10.6 years (range 1.2-30), 142 patients relapsed at a median (range) of 14 (3-129) months; 128 on active surveillance and 14 after adjuvant radiotherapy. The late relapse rate for the active surveillance and adjuvant radiotherapy groups was 4% and 1%, respectively. There was no specific clinicopathological factor associated with late relapse. Isolated para-aortic node(s) was the most common relapse site in active surveillance patients either in late (88%) or early relapse (82%). Among the active surveillance group, no patients with late relapse subsequently developed a second relapse after either salvage radiotherapy (n=25) or chemotherapy (n=6), whereas in early relapse patients a second relapse was reported in seven (10%) of 72 patients treated with salvage radiotherapy and one (4%) of 23 patients who received chemotherapy; all second relapses were subsequently salvaged with chemotherapy. No patient in the adjuvant radiotherapy group developed a second relapse after salvage chemotherapy (n=10) or inguinal radiotherapy/surgery (n=4). Of seven deaths, only one was related to seminoma. Among active surveillance patients, the 10 year overall survival for late and early relapse groups were 100% and 96% (P = 0.2), whereas the 10 year cancer-specific survival rates were 100% and 99% (P = 0.3), respectively.

CONCLUSIONS

In stage I seminoma, the extent and pattern of late relapse is similar to that for early relapse. For active surveillance patients, selective use of salvage radiotherapy/chemotherapy for relapse results in excellent outcomes regardless of the timing of relapse, whereas salvage radiotherapy for late relapse seems to be associated with a minimal risk of second relapse.

Photometric Compliance of Tablet Screens and Retro-Illuminated Acuity Charts As Visual Acuity Measurement Devices

Mobile technology is increasingly used to measure visual acuity. Standards for chart-based acuity tests specify photometric requirements for luminance, optotype contrast and luminance uniformity. Manufacturers provide some photometric data but little is known about tablet performance for visual acuity testing. This study photometrically characterised seven tablet computers (iPad, Apple inc.) and three ETDRS (Early Treatment Diabetic Retinopathy Study) visual acuity charts with room lights on and off, and compared findings with visual acuity measurement standards. Tablet screen luminance and contrast were measured using nine points across a black and white checkerboard test screen at five arbitrary brightness levels. ETDRS optotypes and adjacent white background luminance and contrast were measured. All seven tablets (room lights off) exceeded the most stringent requirement for mean luminance (≥ 120 cd/m2) providing the nominal brightness setting was above 50%. All exceeded contrast requirement (Weber ≥ 90%) regardless of brightness setting, and five were marginally below the required luminance uniformity threshold (Lmin/Lmax ≥ 80%). Re-assessing three tablets with room lights on made little difference to mean luminance or contrast, and improved luminance uniformity to exceed the threshold. The three EDTRS charts (room lights off) had adequate mean luminance (≥ 120 cd/m2) and Weber contrast (≥ 90%), but all three charts failed to meet the luminance uniformity standard (Lmin/Lmax ≥ 80%). Two charts were operating beyond manufacturer's recommended lamp replacement schedule. With room lights on, chart mean luminance and Weber contrast increased, but two charts still had inadequate luminance uniformity. Tablet computers showed less inter-device variability, higher contrast, and better luminance uniformity than charts in both lights-on and lights-off environments, providing brightness setting was >50%. Overall, iPad tablets matched or marginally out-performed ETDRS charts in terms of photometric compliance with high contrast acuity standards.

Critical care of obese patients during and after spine surgery

Obesity is one of the most prevalent health problems facing the United States today, with a recent JAMA article published in 2014 estimating the prevalence of one third of all adults in the United States being obese. Also, due to technological advancements, the incidence of spine surgeries is growing. Considering these overall increases in both obesity and the performance of spinal surgeries, it can be inferred that more spinal surgery candidates will be obese. Due to this, certain factors must be taken into consideration when dealing with spine surgeries in the obese. Obesity is closely correlated with additional medical comorbidities, including hypertension, coronary artery disease, congestive heart failure, and diabetes mellitus. The pre-operative evaluation may be more difficult, as a more extensive medical evaluation may be needed. Also, adequate radiographic images can be difficult to obtain due to patient size and equipment limitations. Administering anesthesia becomes more difficult, as does proper patient positioning. Post-operatively, the obese patient is at greater risk for reintubation, difficulty with pain control, wound infection and deep vein thrombosis. However, despite these concerns, appropriate clinical outcomes can still be achieved in the obese spine surgical candidate. Obesity, therefore, is not a contraindication to spine surgery, and appropriate patient selection remains the key to obtaining favorable clinical outcomes.

The mammalian target of rapamycin modulates the immunoproteasome system in the heart

The mammalian target of rapamycin (mTOR) plays an important role in cardiac development and function. Inhibition of mTOR by rapamycin has been shown to attenuate pathological cardiac hypertrophy and improve the function of aging heart, accompanied by an inhibition of the cardiac proteasome activity. The current study aimed to determine the potential mechanism(s) by which mTOR inhibition modulates cardiac proteasome. Inhibition of mTOR by rapamycin was found to reduce primarily the immunoproteasome in both H9c2 cells in vitro and mouse heart in vivo, without significant effect on the constitutive proteasome and protein ubiquitination. Concurrent with the reduction of the immunoproteasome, rapamycin reduced two important inflammatory response pathways, the NF-κB and Stat3 signaling. In addition, rapamycin attenuated the induction of the immunoproteasome in H9c2 cells by inflammatory cytokines, including INFγ and TNFα, by suppressing NF-κB signaling. These data indicate that rapamycin indirectly modulated immunoproteasome through the suppression of inflammatory response pathways. Lastly, the role of the immunoproteasome during the development of cardiac hypertrophy was investigated. Administration of a specific inhibitor of the immunoproteasome ONX 0914 attenuated isoproterenol-induced cardiac hypertrophy, suggesting that the immunoproteasome may be involved in the development of cardiac hypertrophy and therefore could be a therapeutic target. In conclusion, rapamycin inhibits the immunoproteasome through its effect on the inflammatory signaling pathways and the immunoproteasome could be a potential therapeutic target for pathological cardiac hypertrophy.

An analysis of the association between prostate cancer risk loci, PSA levels, disease aggressiveness and disease-specific mortality

BACKGROUND

Genome-wide association studies have identified multiple single-nucleotide polymorphsims (SNPs) associated with prostate cancer (PCa). Although these SNPs have been clearly associated with disease risk, their relationship with clinical outcomes is less clear. Our aim was to assess the frequency of known PCa susceptibility alleles within a single institution ascertainment and to correlate risk alleles with disease-specific outcomes.

METHODS

We genotyped 1354 individuals treated for localised PCa between June 1988 and December 2007. Blood samples were prospectively collected and de-identified before being genotyped and matched to phenotypic data. We investigated associations between 61 SNPs and disease-specific end points using multivariable analysis and also determined if SNPs were associated with PSA at diagnosis.

RESULTS

Seven SNPs showed associations on multivariable analysis (P<0.05), rs13385191 with both biochemical recurrence (BR) and castrate metastasis (CM), rs339331 (BR), rs1894292, rs17178655 and rs11067228 (CM), and rs11902236 and rs4857841 PCa-specific mortality. After applying a Bonferroni correction for number of SNPs (P<0.0008), the only persistent significant association was between rs17632542 (KLK3) and PSA levels at diagnosis (P=1.4 × 10(-5)).

CONCLUSIONS

We confirmed that rs17632542 in KLK3 is associated with PSA at diagnosis. No significant association was seen between loci and disease-specific end points when accounting for multiple testing. This provides further evidence that known PCa risk SNPs do not predict likelihood of disease progression.