Adaption reveals a neural code for the visual location of orientation change

We apply an adaptation technique to explore the neural code for the visual location of textures defined by modulation of orientation over space. In showing that adaptation to textures modulated around one orientation shifts the perceived location of textures modulated around a different orientation, we demonstrate the existence of a neural code for the location of orientation change that generalises across orientation content. Using competitive adaptation, we characterise the neural processes underlying this code as single-opponent for orientation, that is with concentric excitatory/inhibitory receptive areas tuned to a single orientation.<br /

A reevaluation of achromatic spatio-temporal vision: nonoriented filters are monocular, they adapt, and can be used for decision making at high flicker speeds

Masking, adaptation, and summation paradigms have been used to investigate the characteristics of early spatio-temporal vision. Each has been taken to provide evidence for (i) oriented and (ii) nonoriented spatial-filtering mechanisms. However, subsequent findings suggest that the evidence for nonoriented mechanisms has been misinterpreted: those experiments might have revealed the characteristics of suppression (eg, gain control), not excitation, or merely the isotropic subunits of the oriented detecting mechanisms. To shed light on this, we used all three paradigms to focus on the ‘high-speed’ corner of spatio-temporal vision (low spatial frequency, high temporal frequency), where cross-oriented achromatic effects are greatest. We used flickering Gabor patches as targets and a 2IFC procedure for monocular, binocular, and dichoptic stimulus presentations. To account for our results, we devised a simple model involving an isotropic monocular filter-stage feeding orientation-tuned binocular filters. Both filter stages are adaptable, and their outputs are available to the decision stage following nonlinear contrast transduction. However, the monocular isotropic filters (i) adapt only to high-speed stimuli—consistent with a magnocellular subcortical substrate—and (ii) benefit decision making only for high-speed stimuli (ie, isotropic monocular outputs are available only for high-speed stimuli). According to this model, the visual processes revealed by masking, adaptation, and summation are related but not identical

Sphincter saving anorectoplasty (SSARP) for the reconstruction of Anorectal malformations

<p>Abstract</p> <p>Background</p> <p>This report describes a new technique of sphincter saving anorectoplasty (SSARP) for the repair of anorectal malformations (ARM).</p> <p>Methods</p> <p>Twenty six males with high ARM were treated with SSARP. Preoperative localization of the center of the muscle complex is facilitated using real time sonography and computed tomography. A soft guide wire is inserted under image control which serves as the route for final pull through of bowel. The operative technique consists of a subcoccygeal approach to dissect the blind rectal pouch. The separation of the rectum from the fistulous communication followed by pull through of the bowel is performed through the same incision. The skin or the levators in the midline posteriorly are not divided. Postoperative anorectal function as assessed by clinical Wingspread scoring was judged as excellent, good, fair and poor. Older patients were examined for sensations of touch, pain, heat and cold in the circumanal skin and the perineum. Electromyography (EMG) was done to assess preoperative and postoperative integrity of external anal sphincter (EAS).</p> <p>Results</p> <p>The patients were separated in 2 groups. The first group, Group I (n = 10), were newborns in whom SSARP was performed as a primary procedure. The second group, Group II (n = 16), were children who underwent an initial colostomy followed by delayed SSARP. There were no operative complications. The follow up ranged from 4 months to 18 months. Group I patients have symmetric anal contraction to stimulation and strong squeeze on digital rectal examination with an average number of bowel movements per day was 3–5. In group II the rate of excellent and good scores was 81% (13/16). All patients have an appropriate size anus and regular bowel actions. There has been no rectal prolapse, or anal stricture. EAS activity and perineal proprioception were preserved postoperatively. Follow up computed tomogram showed central placement the pull through bowel in between the muscle complex.</p> <p>Conclusion</p> <p>The technique of SSARP allows safe and anatomical reconstruction in a significant proportion of patients with ARM's without the need to divide the levator plate and muscle complex. It preserves all the components contributing to superior faecal continence, and avoids the potential complications associated with the open posterior sagittal approach.</p

Diagnostic and cost utility of whole exome sequencing in peripheral neuropathy.

OBJECTIVE: To explore the diagnostic utility and cost effectiveness of whole exome sequencing (WES) in a cohort of individuals with peripheral neuropathy. METHODS: Singleton WES was performed in individuals recruited though one pediatric and one adult tertiary center between February 2014 and December 2015. Initial analysis was restricted to a virtual panel of 55 genes associated with peripheral neuropathies. Patients with uninformative results underwent expanded analysis of the WES data. Data on the cost of prior investigations and assessments performed for diagnostic purposes in each patient was collected. RESULTS: Fifty patients with a peripheral neuropathy were recruited (median age 18 years; range 2-68 years). The median time from initial presentation to study enrollment was 6 years 9 months (range 2 months-62 years), and the average cost of prior investigations and assessments for diagnostic purposes AU$4013 per patient. Eleven individuals received a diagnosis from the virtual panel. Eight individuals received a diagnosis following expanded analysis of the WES data, increasing the overall diagnostic yield to 38%. Two additional individuals were diagnosed with pathogenic copy number variants through SNP microarray. CONCLUSIONS: This study provides evidence that WES has a high diagnostic utility and is cost effective in patients with a peripheral neuropathy. Expanded analysis of WES data significantly improves the diagnostic yield in patients in whom a diagnosis is not found on the initial targeted analysis. This is primarily due to diagnosis of conditions caused by newly discovered genes and the resolution of complex and atypical phenotypes

Anorectal malformations

Anorectal malformations comprise a wide spectrum of diseases, which can affect boys and girls, and involve the distal anus and rectum as well as the urinary and genital tracts. They occur in approximately 1 in 5000 live births. Defects range from the very minor and easily treated with an excellent functional prognosis, to those that are complex, difficult to manage, are often associated with other anomalies, and have a poor functional prognosis. The surgical approach to repairing these defects changed dramatically in 1980 with the introduction of the posterior sagittal approach, which allowed surgeons to view the anatomy of these defects clearly, to repair them under direct vision, and to learn about the complex anatomic arrangement of the junction of rectum and genitourinary tract. Better imaging techniques, and a better knowledge of the anatomy and physiology of the pelvic structures at birth have refined diagnosis and initial management, and the analysis of large series of patients allows better prediction of associated anomalies and functional prognosis. The main concerns for the surgeon in correcting these anomalies are bowel control, urinary control, and sexual function. With early diagnosis, management of associated anomalies and efficient meticulous surgical repair, patients have the best chance for a good functional outcome. Fecal and urinary incontinence can occur even with an excellent anatomic repair, due mainly to associated problems such as a poorly developed sacrum, deficient nerve supply, and spinal cord anomalies. For these patients, an effective bowel management program, including enema and dietary restrictions has been devised to improve their quality of life

The New Urban Agenda: key opportunities and challenges for policy and practice

The UN-HABITAT III conference held in Quito in late 2016 enshrined the first Sustainable Development Goal (SDG) with an exclusively urban focus. SDG 11, as it became known, aims to make cities more inclusive, safe, resilient and sustainable through a range of metrics, indicators, and evaluation systems. It also became part of a post-Quito ‘New Urban Agenda’ that is still taking shape. This paper raises questions around the potential for reductionism in this new agenda, and argues for the reflexive need to be aware of the types of urban space that are potentially sidelined by the new trends in global urban policy

A tumor focused approach to resolving the etiology of DNA mismatch repair deficient tumors classified as suspected Lynch syndrome

Published online 26 April 2023Routine screening of tumors for DNA mismatch repair (MMR) deficiency (dMMR) in colorectal (CRC), endometrial (EC) and sebaceous skin (SST) tumors leads to a significant proportion of unresolved cases classified as suspected Lynch syndrome (SLS). SLS cases (n = 135) were recruited from Family Cancer Clinics across Australia and New Zealand. Targeted panel sequencing was performed on tumor (n = 137; 80×CRCs, 33×ECs and 24xSSTs) and matched blood-derived DNA to assess for microsatellite instability status, tumor mutation burden, COSMIC tumor mutational signatures and to identify germline and somatic MMR gene variants. MMR immunohistochemistry (IHC) and MLH1 promoter methylation were repeated. In total, 86.9% of the 137 SLS tumors could be resolved into established subtypes. For 22.6% of these resolved SLS cases, primary MLH1 epimutations (2.2%) as well as previously undetected germline MMR pathogenic variants (1.5%), tumor MLH1 methylation (13.1%) or false positive dMMR IHC (5.8%) results were identified. Double somatic MMR gene mutations were the major cause of dMMR identified across each tumor type (73.9% of resolved cases, 64.2% overall, 70% of CRC, 45.5% of ECs and 70.8% of SSTs). The unresolved SLS tumors (13.1%) comprised tumors with only a single somatic (7.3%) or no somatic (5.8%) MMR gene mutations. A tumor-focused testing approach reclassified 86.9% of SLS into Lynch syndrome, sporadic dMMR or MMR-proficient cases. These findings support the incorporation of tumor sequencing and alternate MLH1 methylation assays into clinical diagnostics to reduce the number of SLS patients and provide more appropriate surveillance and screening recommendations.Romy Walker ... Nicola Poplawski ... et al. and for the Family Cancer Clinics of Australi