Optogenetic Control by Pulsed Illumination.

Sensory photoreceptors evoke numerous adaptive responses in nature and serve as light-gated actuators in optogenetics to enable the spatiotemporally precise, reversible, and noninvasive control of cellular events. The output of optogenetic circuits can often be dialed in by varying illumination quality, quantity, and duration. A programmable matrix of light-emitting diodes has been devised to efficiently probe the response of optogenetic systems to intermittently applied light of varying intensity and pulse frequency. Circuits for light-regulated gene expression markedly differed in their responses to pulsed illumination of a single color which sufficed for their sequential triggering. In addition to quantity and quality, the pulse frequency of intermittent light hence provides a further input variable for output control in optogenetics and photobiology. Pulsed illumination schemes allow the reduction of overall light dose and facilitate the multiplexing of several lightdependent actuators and reporters.

Early-Life Human Microbiota Associated With Childhood Allergy Promotes the T Helper 17 Axis in Mice.

The intestinal microbiota influences immune maturation during childhood, and is implicated in early-life allergy development. However, to directly study intestinal microbes and gut immune responses in infants is difficult. To investigate how different types of early-life gut microbiota affect immune development, we collected fecal samples from children with different allergic heredity (AH) and inoculated germ-free mice. Immune responses and microbiota composition were evaluated in the offspring of these mice. Microbial composition in the small intestine, the cecum and the colon were determined by 16S rRNA sequencing. The intestinal microbiota differed markedly between the groups of mice, but only exposure to microbiota associated with AH and known future allergy in children resulted in a T helper 17 (Th17)-signature, both systemically and in the gut mucosa in the mouse offspring. These Th17 responses could be signs of a particular microbiota and a shift in immune development, ultimately resulting in an increased risk of allergy.

Perineal ultrasound as a complement to POP-Q in the assessment of cystoceles.

PURPOSE: In the present study we want to propose a classification system to quantify cystoceles by perineal ultrasound (PUS). MATERIALS AND METHODS: 120 PUS data were analyzed measuring the distance between the lowest point of the bladder and the midpubic line (MPL) during rest and Valsalva. Results were classified into groups and compared to POP-Q using the κ-coefficient. Results for exact bladder position were checked for interrater reliability using ICC and Pearson's coefficient and results for classification were checked using the κ-coefficient. Bladder positions at rest and Valsalva were correlated with the distance between these points. RESULTS: Highly significant differences concerning the position at rest and the distance between rest and Valsalva were found between the groups. For the interrater agreement, the Pearson correlation coefficient was ρ = 0.98, the ICC (A-1) = 0.98, and κ = 1.00. Comparing the classification results for POP-Q and PUS, the kappa-coefficient was κ = 0.65. CONCLUSION: PUS using the MPL and the classification system is a highly reliable tool for the evaluation of cystoceles. PUS shows good correlation with POP-Q. Furthermore, PUS offers a doubtless identification of the descending organ. Further studies are needed to evaluate the clinical use of the classification system proposed here.

Visualization of polypropylene and polyvinylidene fluoride slings in perineal ultrasound and correlation with clinical outcome.

INTRODUCTION AND HYPOTHESIS: Complications and malfunctioning after TOT can occur due to several factors, such as the material of the sling. The aim of the present study is to evaluate morphology and functionality of two types of slings (PVDF; polypropylene) in vivo using perineal ultrasound (PUS). MATERIALS: In n = 47 women with TOT four criteria for PUS were taken and checked for possible differences: vertical stability of the sling position during Valsalva manoeuvre and contraction; distance "sling to urethra"; width of the sling and condition of the selvedges. RESULTS: We observed an increased vertical displacement of the PP-slings, a significantly smaller variance to the extent of the displacement in PVDF-slings (P < 0.01), a significantly larger distance between sling and urethra (P < 0.001) in PVDF-slings, and a significantly smaller width of the PP-slings (P < 0.0001). CONCLUSION: Significant differences were found between the slings according to the four criteria. There was no difference established between the slings in the improvement of continence and no significant influence of the parameters was found for the resulting state of continence. In future studies, PUS may help to link differences in the morphology and functionality of in vivo slings to their material properties.

Sensitivity, reproducibility, and reliability of self-paced versus fixed stimulus presentation in an fMRI study on exact, non-symbolic arithmetic in typically developing children aged between 6 and 12 years.

Fixed stimulus presentation times pose several methodological problems for developmental functional magnetic resonance imaging (fMRI) studies that can be avoided by self-paced study designs. Yet, methodological issues of self-paced stimulus presentation for fMRI studies are largely understudied. Therefore, we compared sensitivity, reproducibility, and reliability of neural activation of a fixed and a self-paced design for an exact, non-symbolic addition paradigm in a sample of children aged 6-12 years. Both design types were comparable in sensitivity, and the self-paced design was superior in reproducibility and reliability. Therefore, self-paced study designs seem to be a valid option for developmental fMRI studies on higher cognition.