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Human activity is leaving a pervasive and persistent signature on Earth. Vigorous debate continues about whether this warrants recognition as a new geologic time unit known as the Anthropocene. We review anthropogenic markers of functional changes in the Earth system through the stratigraphic record. The appearance of manufactured materials in sediments, including aluminum, plastics, and concrete, coincides with global spikes in fallout radionuclides and particulates from fossil fuel combustion. Carbon, nitrogen, and phosphorus cycles have been substantially modified over the past century. Rates of sea-level rise and the extent of human perturbation of the climate system exceed Late Holocene changes. Biotic changes include species invasions worldwide and accelerating rates of extinction. These combined signals render the Anthropocene stratigraphically distinct from the Holocene and earlier epochs., (Copyright © 2016, American Association for the Advancement of Science.)

Aim: Risk-reducing mastectomy (RRM) is on the increase, now frequently combined with breast reconstruction (BR). However, the resource implications associated with bilateral mastectomy and reconstruction are unknown. This study assessed the overall cost of performing risk-reducing surgery., Methods: All cases of RRM and BR performed between 1991 and 2011 at this hospital were identified from a prospectively collected database. All patients undergoing bilateral mastectomy were included, when at least one mastectomy was risk-reducing. Overall treatment costs for all surgical procedures, complications, revisional procedures and outpatient attendances were calculated and compared to the National Tariff allowed. Mann-Whitney U and Fischer's exact tests were used to calculate levels of significance., Results: Fifty patients underwent bilateral mastectomy and BR (median follow up 20 [range 1-106] months), 72 were Latissimus Dorsi reconstructions (LDR) and 28 were Subpectoral reconstructions (SPR). LDR took longer than SPR (p = 0.001), with a greater length of stay (p = 0.024). Nine percent of patients returned to theatre for early complications, but the type of BR did not influence the early complication rate (LDR versus SPR, p = 0.345) or the need for additional unplanned procedures (LDR versus SPR, p = 0.671). The overall mean cost for bilateral RRM and BR was £14,797 per patient. The inpatient cost for bilateral RRM and LDR was £10,082 compared with £5,905 SPR. Both procedures exceeded the £5,697 tariff allowed in the UK., Conclusion: Bilateral RRM and BR is a safe procedure, but the resource implications are considerable and exceed the tariff allowed, particularly when performing more complex techniques., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Background: Peripheral nerves straighten and stretch in order to accommodate increases in bed length during joint movements. The ulnar nerve is predicted to show large bed length changes, particularly on elbow flexion. The present study examines sliding of the ulnar nerve during limb movements, to determine how far these changes are accommodated by straightening and stretch., Methods: Ultrasound imaging was used to measure longitudinal nerve sliding in the forearm and upper arm during 40 degrees wrist extension, 90 degrees elbow flexion and 50 degrees shoulder abduction. Nerve trunk folding in the upper arm was measured from still ultrasound images taken in a series of limb positions from 40 degrees shoulder abduction, elbow extended and wrist neutral to full elbow flexion, 90 degrees shoulder abduction and wrist extension, a position designed to stretch the ulnar nerve., Findings: Wrist extension led to clear nerve sliding in the forearm with movements of up to 4 mm. However, shoulder abduction and elbow flexion caused remarkably little nerve movement. Images of the ulnar nerve showed considerable curvature with 40 degrees shoulder abduction and elbow extension but a much straighter path with the elbow flexed., Interpretation: The ulnar nerve appears unloaded and follows a wavy path in most functional upper limb positions. During elbow and shoulder movements, changes in bed length appear to be accommodated largely by straightening of the nerve path, with only modest stretch of the nerve itself when the elbow flexes. The ulnar nerve is thus well adapted for the large changes in bed length that occur during limb movements.

Schwann cells play a central role in peripheral-nerve regeneration, in which it has been shown that the addition of exogenous Schwann cells enhances the temporal and spatial sequence of events observed in regeneration. In this study, the authors investigated the fate of exogenous cells in this process by using fluorescently tagged autogenous Schwann cells in an established rat model of peripheral-nerve regeneration. Tracking labeled cells over a 4-week period revealed early migration of Schwann cells into the proximal nerve segment, followed by a concentration of migrating Schwann cells, leading the proximal growth cone throughout the regenerative process. The early proximal distribution of labeled cells suggests active migration in response to nerve damage, with spatial localization at the center of the proximal nerve segment and not the epineural surface. These observations demonstrate an interaction of exogenous Schwann cells with intact nerve tissue in vivo and affirm their role in the directional growth of regenerating axons.

Background & Aims: Src activation is reported as an early event found in preneoplastic colonic adenomas and in 70% of colon carcinomas. The aim of this study was to identify the biological consequences of c-src overexpression in rat colon epithelial cells., Methods: Introduction and overexpression of c-src in an immortalized rat colon epithelial cell line was achieved using lipofection. Transfectants were tested for changes in growth and cell behavior using different in vitro assay systems., Results: Colon epithelial cells overexpressing c-src showed the ability to form microcolonies in soft agar without acquiring tumorigenic potential. In in vitro assays, c-src transfectants displayed a gain of invasive potential through Matrigel without an accompanying change in migrational ability. No discernible qualitative changes were observed in the phosphotyrosyl protein profile between c-src and v-src transfectants. Assessment of the cadherin/catenin status in these cells revealed an intact, functional complex with no detectable tyrosine phosphorylation of different components of the complex., Conclusions: Overexpression of c-src in an immortalized rat colon epithelial cell line does not elicit full neoplastic transformation but enhances anchorage-independent growth and confers invasion capability. Increased invasion through Matrigel was not linked to inactivation of the cadherin complex in c-src transfectants.

Immersion in water in spas has been practised for centuries and has many proponents. Despite fierce debate about its efficacy there has been little scientific evaluation of the effect of immersion in mineral waters. Eight normal subjects were immersed in Bath spa water for two hours and the renal, haematological, and cardiovascular responses were compared with those in the control periods before and after immersion. Significant, twofold diuresis and natriuresis, 5% haemodilution, and a 50% increase in cardiac index were observed in subjects immersed, sitting, in Bath spa water at 35 degrees C. These changes may constitute part of the scientific rationale for spa treatment in many states of disease.