The various forms of sensorimotor plasticity following limb amputation and their link with rehabilitation strategies

Limb amputation is characterized by complex and intermingled brain reorganization processes combining sensorimotor deprivation induced by the loss of the limb per se, and compensatory behaviors, such as the over-use of the intact or remaining limb. While a large body of evidence documents sensorimotor representation plasticity following arm amputation, less investigations have been performed to fully understand the use-dependent plasticity phenomenon and the role of behavioral compensation in brain reorganization. In this article, I will review the findings on sensorimotor plasticity after limb amputation, focusing on these two aspects: sensorimotor deprivation and adaptive patterns of limb usage, and describe the models that attempt to link these reorganizational processes with phantom limb pain. Two main models have been proposed: the maladaptive plasticity model which states that the reorganization of the adjacent cortical territories into the representation of the missing limb is proportional to phantom pain intensity, and the persistent representation model, which rather suggests that the intensity of residual brain activity associated with phantom hand movements scales with phantom limb pain intensity. I will finally illustrate how this fundamental research helps designing new therapeutic strategies for phantom plain relief.

VECMAtk: a scalable verification, validation and uncertainty quantification toolkit for scientific simulations

We present the VECMA toolkit (VECMAtk), a flexible software environment for single and multiscale simulations that introduces directly applicable and reusable procedures for verification, validation (V&V), sensitivity analysis (SA) and uncertainty quantication (UQ). It enables users to verify key aspects of their applications, systematically compare and validate the simulation outputs against observational or benchmark data, and run simulations conveniently on any platform from the desktop to current multi-petascale computers. In this sequel to our paper on VECMAtk which we presented last year [1] we focus on a range of functional and performance improvements that we have introduced, cover newly introduced components, and applications examples from seven different domains such as conflict modelling and environmental sciences. We also present several implemented patterns for UQ/SA and V&V, and guide the reader through one example concerning COVID-19 modelling in detail. This article is part of the theme issue 'Reliability and reproducibility in computational science: implementing verification, validation and uncertainty quantification in silico'.

Are there regional tendencies toward controversial screening practices? A study of prostate and breast cancer screening in a Medicare population

INTRODUCTION

Prostate and breast cancer screening in older patients continue to be controversial. Balancing the desire for early detection with avoidance of over-diagnosis has led to competing and contradictory guidelines for both practices. Despite similarities, it is not known how these screening practices are related at the regional level. In this study, we examined how screening PSA and mammography are related within healthcare regions, and, to better understand what may be driving these practices, whether they are associated with local intensity of care.

METHODS

We performed a retrospective cross-sectional study of fee-for-service Medicare beneficiaries in 2012. For each of 306 hospital referral regions (HRRs), we calculated rates of PSA screening for men aged ≥68 years, as well as rates of screening mammography for women aged ≥75 years, adjusted for age and race. Additionally, we determined regional rates of "healthcare intensity", including spending on tests and procedures, and intensity of end-of-life care. Pearson correlations of adjusted rates were calculated within HRRs.

RESULTS

The mean adjusted rate of PSA screening was 22%. The mean age of screened and unscreened patients was 75.0 and 77.4 years, respectively (p<0.0001). The mean adjusted rate of screening mammography was 23%; mean ages of screened and non-screened women were 79.95 and 83.67, respectively (p<0.0001). HRR-level PSA screening rates were independent of screening mammography rates (r=0.06, p=0.31). PSA screening rates were associated with spending on testing and procedures (r=0.42, p<0.0001) and various measures of intensity of EOL care (e.g. r=0.40, p<0.0001 for mechanical ventilator use). Screening mammography had low correlation with both health care spending and EOL care intensity measures (all r-values <0.3).

CONCLUSIONS

Regional rates of PSA screening rates were independent of screening mammography, thus these practices appear to be driven by different factors. Unlike mammography, PSA screening was associated with local enthusiasm for testing and treatment. Efforts to reduce over-testing should contemplate these practices differently, and future research should examine the factors motivating these screening practices.

Pneumoscrotum With Extensive Penile and Abdominal Subcutaneous Emphysema: A Case Report of Uncertain Etiology

Pneumoscrotum and subcutaneous emphysema make for impressive findings on examination and imaging. With ranging etiologies, thorough investigation into the source is essential to rule out potentially life threatening situations. We present a 31-year-old man with pneumoscrotum and extensive subcutaneous emphysema of his penis, abdomen, and perineum. History and physical exam didn't reveal a clear cause and he subsequently underwent surgical exploration showing no soft tissue infection. On post-operative day 1, he remained clinically stable and was discharged. Despite the usual benign nature of pneumoscrotum, full assessment is necessary to identify possible underlying conditions of significant morbidity and mortality.

What factors are associated with unplanned return following transurethral resection of bladder tumor? An analysis of a large single institution's experience

OBJECTIVE

This study sought to evaluate factors associated with unplanned hospital return (UR) following transurethral resection of bladder tumor (TURBT), the largest source of readmission among ambulatory urological procedures.

MATERIALS AND METHODS

A retrospective review of TURBTs at a single academic institution between April 2011 and August 2014 was performed. Demographics, comorbidities, length of stay, tumor size and multiple other factors were recorded. UR was recorded within 30 days of surgery. Bivariate and multivariable analyses were performed to determine factors associated with UR.

RESULTS

Among 708 patients undergoing TURBT, 23.9% were female with a mean age of 70 years. The rate of UR was 10.9%. The most common cause of UR was gross hematuria, accounting for 70%. On bivariate analysis, Foley catheter placement in the operating room, non-aspirin anticoagulation and index length of stay longer than 24 h were associated with hematuria-related UR (p < 0.05). Preoperative antibiotics, female gender and aspirin therapy were associated with lower rates of hematuria-related UR (p < 0.05), while tumor size, distance of residence to the hospital, and Foley on hospital discharge (rather than from the operating room) had no association (p > 0.05). On multivariable analysis, only Foley placement in the operating room remained associated with higher rates of hematuria-related UR, while preoperative antibiotics, female gender and aspirin therapy remained associated with a lower likelihood of this event.

CONCLUSIONS

UR following TURBT is common and typically results from gross hematuria. Patients with postoperative Foley catheterization in the operating room may require additional counseling or supervision before discharge, and should be considered for discharge with a Foley rather than having a prompt voiding trial.

Success factors for the future survival of rural hospitals

Rural hospitals are among those at greatest risk in the changing world of healthcare delivery. There are, however, those that are continuing to thrive despite the odds. The common thread among these are factors found in select Midwest rural hospitals.

[Primary intracranial and intraspinal neoplasms in Denmark 1943-1987]

This is a descriptive study of primary intracranial and intraspinal tumours notified to the national Danish Cancer Registry during the years 1943-1987. A total of 19,317 cases of benign and malignant neoplasms were included over these 45 years with a doubling of the age-standardized incidence rates for both men and women from start till end of the registration period. The trend was mainly explained by markedly increasing rates in the age groups 60 years or above at diagnosis. Approximately some 74% of tumours were derived from the brain tissues and 19% from the intracranial and intraspinal meninges. Meningiomas predominate among women with a male:female ratio of 0.5, while tumours of the brain tissues predominate among men (ratio 1.3). Meningiomas are more frequently encountered as a chance finding at autopsy compared to other types of intracranial and intraspinal tumours. The above-mentioned increase in age-specific incidence is due mainly to improved diagnostic capabilities over the period and a subsequent decrease in the underreporting of these tumour types.