Comparison of esophageal submucosal glands in experimental models for esophagus tissue engineering applications

Abstract

Objective

Esophagus tissue engineering holds promises to overcome the limitations of the presently employed esophageal replacement procedures. This study investigated 5 animal models for esophageal submucosal glands (ESMG) to identify models appropriate for regenerative medicine applications. Furthermore, this study aimed to measure geometric parameters of ESMG that could be utilized for fabrication of ESMG-specific scaffolds for esophagus tissue engineering applications.

Methods

Ovine, avian, bovine, murine, and porcine esophagus were investigated using Hematoxylin–Eosin (HE), Periodic Acid Schiff (PAS), and Alcian Blue (AB), with AB applied in 3 pH levels (0.2, 1.0, and 2.5) to detect sulphated mucous. Celleye^® (version F) was employed to gain parametric data on ESMGs (size, perimeter, distance to lumen, and acini concentration) necessary for scaffold fabrication.

Results

Murine, bovine, and ovine esophagus were devoid of ESMG. Avian esophagus demonstrated sulphated acid mucous producing ESMGs with a holocrine secretion pattern, whereas sulphated acid and neutral mucous producing ESMGs with a merocrine secretion pattern were observed in porcine esophagus. Distance of ESMGs to lumen ranged from 127–340 μm (avian) to 916–983 μm (porcine). ESMGs comprised 35% (avian) to 45% (porcine) area of the submucosa. ESMG had an area of 125000 μm² (avian) to 580000 μm² (porcine).

Conclusion

Avian and porcine esophagus possesses ESMGs. However, porcine esophagus correlates with data available on human ESMGs. Geometric and parametric data obtained from ESMG are valuable for the fabrication of ESMG-specific scaffolds for esophagus tissue engineering using the hybrid construct approach.

Complete lymph node dissection or observation in melanoma patients with multiple positive sentinel lymph nodes: A single‐center retrospective analysis

The Journal of Dermatology, EarlyView.

Communications principles for inviting inquiry and exploration through science and data visualization

Abstract

Science, in the popular imagination, is about finding answers to questions. Scientists make discoveries, develop theories, and deliver those discoveries and theories to audiences with an interest in the truth as backed up by science. Well-designed data visualization (dataviz), by contrast, can generate and address not only new questions but new kinds of questions. It has the particular quality of allowing its viewers, users and makers the ability to generate new inquiries, and to put them in a better place to answer them. Dataviz offers aesthetic and interactive platforms for discussion and inquiry that can help scientists to both do their work and better communicate their work to broader audiences.Here I will illustrate and examine case studies from multiple points along the rich and varied possibility space that opens up when science and dataviz work together. I will also introduce three communication principles that I have learned from my involvement with hundreds of dataviz projects over the years. Well-designed dataviz can help scientists and those involved with science find ways to navigate the multiple competing interests and priorities inherent in both communication to non-scientists and exploratory data-rich interfaces.http://sicb.org/meetings/2018/abstracts/correctsymposia.php

Sexually dimorphic eye-loss driven by ecological selection in an ostracod crustacean: support for the reproductive role hypothesis

Abstract

Euphilomedes carcharodonta ostracods exhibit sex-specific eye-loss, with females lacking image-forming compound eyes compared to males and related species. The standard assumption is that sexual dimorphism is driven by sexual selection. However, previous work in E. carcharodonta suggests that male eyes are used to evade predators in the male-specific ecological niche, and that male-eyes lack the resolution to search for females. In this study, we examine whether sexual selection or ecological selection drives the retention of male eyes. Ecological niche differentiation was hypothesized by Darwin (1871) to be an alternative selective force for sexual dimorphism either through food competition or through dimorphic sex-role behavior, the reproductive role hypothesis. As of yet, there is little experimental evidence supporting this hypothesis. Here, we experimentally blindfold male E. carcharodonta to mimic the female phenotype and examine the effects on sex-specific niches and behavior. Blindfolding does not appear to grossly change male behavior, nor do females behave differently when exposed to blindfolded males. This leads us to conclude that the development of complex eyes in male E. arises from ecological selection rather than sexual selection.

Correction to: Estimating the Reproducibility of Experimental Philosophy

Appendix 1 was incomplete in the initial online publication. The original article has been corrected.

Bildgebende radiologische Diagnostik und Verlaufsbeurteilung beim HCC

Zusammenfassung

Hintergrund

Die bildgebende radiologische Diagnostik ist heute aus den Untersuchungen beim hepatozellulären Karzinom (HCC) nicht mehr wegzudenken. Die Multidetektor-Computertomographie (CT) und Magnetresonanztomographie (MRT) spielen hierbei eine entscheidende Rolle. Die Kontrastmittelsonographie (CE-US, „contrast enhanced ultrasound") stellt zudem für die Charakterisierung des HCC bei einer in der B‑Bild-Sonographie zufällig entdeckten Leberläsion bei Hochrisikopatienten eine Alternative dar.

Methode

Es wurden eine Recherche und Analyse aktueller Literatur durchgeführt.

Ergebnisse

Die CT ist als schnell und universell verfügbare Bildgebungsmodalität eine wichtige Methode zur Diagnostik des HCC. Sie profitiert von den technischen Weiterentwicklungen der letzten Jahrzehnte, die sich neben reduzierter Strahlendosis v. a. in schnellerer Akquisition niederschlagen. Mit der MRT können noch weitere Diagnosekriterien für die Evaluation und Differenzialdiagnose von fokalen Leberläsionen in der zirrhotischen Leber herangezogen werden. Sie ist heute ausreichend robust, um bei den allermeisten Patienten adäquate Bilder zu generieren. Die CE-US ist in der aktuellen nationalen S3-Leitlinie zur Diagnostik und Therapie des HCC als alternatives bildgebendes Verfahren zur CT und MRT für die Charakterisierung des HCC empfohlen, wenn ein unklarer Leberrundherd unabhängig von seiner Größe in einer Hochrisikogruppe in der B‑Bild-Sonographie detektiert wird. Die Vorteile liegen in den geringen Kosten, der raschen Verfügbarkeit, der fehlenden Strahlenbelastung und der fehlenden Nephrotoxizität. Im klinischen Alltag hat sich die Responsebeurteilung mit den mRECIST-Kriterien beim HCC weitestgehend durchgesetzt.

Coastal erosion—a “new” land-based source of labile mercury to the marine environment

Abstract

Mercury (Hg) can be introduced into the marine environment in many different ways. In the case of the Baltic Sea, rivers and atmospheric deposition are the predominant ones. However, in the face of ongoing climate change, a new potential source, coastal erosion, is starting to become more important and is currently considered to be the third largest source of Hg in the Gdansk Basin region. It is especially significant along sections of coastline where, due to the higher frequency of extreme natural phenomena such as storms, heavy rains, and floods, increased erosion processes have already been noted. Cliffs, which account for about 20% of the Polish coastline, are particularly vulnerable. The aim of the study was to estimate the annual load of labile Hg entering the Gdansk Basin as a result of coastal erosion. Samples of down-core sediments (0–65 cm) were collected in the years 2016–2017 from selected cliffs situated in the Gulf of Gdansk area. The thermodesorption method was used to distinguish between labile and stable fractions of Hg. Considering the mean total Hg concentrations in the collected sediments (9.7 ng g⁻¹) and the mean share of labile (64%), bioavailable mercury, it was estimated that the load of labile Hg originating from coastal erosion entering the Gdansk Basin is 10.0 kg per year. The load can increase by up to 50% in the case of episodic abrasion events during heavy storms and rains.

Deterrence and Norms to Foster Stability in Cyberspace

Abstract

Deterrence in cyberspace is possible. But it requires an effort to develop a new domain-specific, conceptual, normative, and strategic framework. To be successful, cyber deterrence needs to shift from threatening to prevailing. I argue that by itself, deterrence is insufficient to ensure stability of cyberspace. An international regime of norms regulating state behaviour in cyberspace is necessary to complement cyber deterrence strategies and foster stability. Enforcing this regime requires an authority able to ensure States compliance with the norms at an international level, run investigations into suspected State-run (or Statesponsored) cyber operations to define attribution, expose breaches of the norms, and impose adequate sanctions and punishments. These requirements define a political mandate for an authority that will have a deep impact on international relations and geo-political equilibriums. The UN Security Council has the necessary resources and the political and coercive power to meet these requirements. The time has come to embrace this power to consolidate and enforce an international regime of norms to regulate state behaviour in cyberspace. Problems, mistakes, and even failures are to be expected, but they must not hinder the process.

Blunt Cerebrovascular Injuries: Advances in Screening, Imaging, and Management Trends [LETTERS]

Reply: [LETTERS]

Simultaneous Bipedicular Radiofrequency Ablation Combined with Vertebral Augmentation for Local Tumor Control of Spinal Metastases [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

Percutaneous radiofrequency ablation combined with vertebral augmentation has emerged as a minimally invasive treatment for patients with vertebral metastases who do not respond to or have contraindications to radiation therapy. The prevalence of posterior vertebral body metastases presents access and treatment challenges in the unique anatomy of the spine. The purpose of this study was to evaluate the safety and efficacy of simultaneous bipedicular radiofrequency ablation using articulating bipolar electrodes combined with vertebral augmentation for local tumor control of spinal metastases.

MATERIALS AND METHODS:

Imaging-guided simultaneous bipedicular radiofrequency ablation combined with vertebral augmentation was performed in 27 patients (33 tumors) with vertebral metastases selected following multidisciplinary consultations, to achieve local tumor control in this retrospective study. Tumor characteristics, procedural details, and complications were documented. Pre- and postprocedural cross-sectional imaging was evaluated to assess local tumor control rates.

RESULTS:

Thirty-three tumors were successfully ablated in 27 patients. Posterior vertebral body or pedicle involvement or both were present in 94% (31/33) of cases. Sixty-seven percent (22/33) of the tumors involved ≥75% of the vertebral body volume. Posttreatment imaging was available for 79% (26/33) of the treated tumors. Local tumor control was achieved in 96% (25/26) of tumors median imaging follow up of 16 weeks. No complications were reported, and no patients had clinical evidence of metastatic spinal cord compression at the treated levels.

CONCLUSIONS:

Simultaneous bipedicular radiofrequency ablation combined with vertebral augmentation is safe and effective for local tumor control of vertebral metastases. Articulating bipolar electrodes enable the placement and proximity necessary for optimal confluence of the ablation zones. Local tumor control may lead to more durable pain palliation, prevent disease progression, and reduce skeletal-related events of the spine.

Evaluation of Thick-Slab Overlapping MIP Images of Contrast-Enhanced 3D T1-Weighted CUBE for Detection of Intracranial Metastases: A Pilot Study for Comparison of Lesion Detection, Interpretation Time, and Sensitivity with Nonoverlapping CUBE MIP, CUBE, and Inversion-Recovery-Prepared Fast-Spoiled Gradient Recalled Brain Volume [ADULT BRAIN]

BACKGROUND AND PURPOSE:

Early and accurate identification of cerebral metastases is important for prognostication and treatment planning although this process is often time consuming and labor intensive, especially with the hundreds of images associated with 3D volumetric imaging. This study aimed to evaluate the benefits of thick-slab overlapping MIPs constructed from contrast-enhanced T1-weighted CUBE (overlapping CUBE MIP) for the detection of brain metastases in comparison with traditional CUBE and inversion-recovery prepared fast-spoiled gradient recalled brain volume (IR-FSPGR-BRAVO) and nonoverlapping CUBE MIP.

MATERIALS AND METHODS:

A retrospective review of 48 patients with cerebral metastases was performed at our institution from June 2016 to October 2017. Brain MRIs, which were acquired on multiple 3T scanners, included gadolinium-enhanced T1-weighted IR-FSPGR-BRAVO and CUBE, with subsequent generation of nonoverlapping CUBE MIP and overlapping CUBE MIP. Two blinded radiologists identified the total number and location of metastases on each image type. The Cohen was used to determine interrater agreement. Sensitivity, interpretation time, and lesion contrast-to-noise ratio were assessed.

RESULTS:

Interrater agreement for identification of metastases was fair-to-moderate for all image types ( = 0.222–0.598). The total number of metastases identified was not significantly different across the image types. Interpretation time for CUBE MIPs was significantly shorter than for CUBE and IR-FSPGR-BRAVO, saving at least 50 seconds per case on average (P < .001). The mean lesion contrast-to-noise ratio for both CUBE MIPs was higher than for IR-FSPGR-BRAVO. The mean contrast-to-noise ratio for small lesions (<4 mm) was lower for nonoverlapping CUBE MIP (1.55) than for overlapping CUBE MIP (2.35). For both readers, the sensitivity for lesion detection was high for all image types but highest for overlapping CUBE MIP and CUBE (0.93–0.97).

CONCLUSIONS:

This study suggests that the use of overlapping CUBE MIP or nonoverlapping CUBE MIP for the detection of brain metastases can reduce interpretation time without sacrificing sensitivity, though the contrast-to-noise ratio of lesions is highest for overlapping CUBE MIP.

Quantitative MRI of Perivascular Spaces at 3T for Early Diagnosis of Mild Cognitive Impairment [ADULT BRAIN]

BACKGROUND AND PURPOSE:

The limitations inherent in the current methods of diagnosing mild cognitive impairment have constrained the use of early therapeutic interventions to delay the progression of mild cognitive impairment to dementia. This study evaluated whether quantifying enlarged perivascular spaces observed on MR imaging can help differentiate those with mild cognitive impairment from cognitively healthy controls and, thus, have an application in the diagnosis of mild cognitive impairment.

MATERIALS AND METHODS:

We automated the identification of enlarged perivascular spaces in brain MR Images using a custom quantitative program designed with Matlab. We then quantified the densities of enlarged perivascular spaces for patients with mild cognitive impairment (n = 14) and age-matched cognitively healthy controls (n = 15) and compared them to determine whether the density of enlarged perivascular spaces can serve as an imaging surrogate for mild cognitive impairment diagnosis.

RESULTS:

Quantified as a percentage of volume fraction (v/v%), densities of enlarged perivascular spaces were calculated to be 2.82 ± 0.40 v/v% for controls and 4.17 ± 0.57 v/v% for the mild cognitive impairment group in the subcortical brain (P < .001), and 2.74 ± 0.57 v/v% for the controls and 3.90 ± 0.62 v/v% for the mild cognitive impairment cohort in the basal ganglia (P < .001). Maximum intensity projections exhibited a visually conspicuous difference in the distributions of enlarged perivascular spaces for a patient with mild cognitive impairment and a control patient. By means of receiver operating characteristic curve analysis, we determined the sensitivity and specificity of using enlarged perivascular spaces as a differentiating biomarker between mild cognitive impairment and controls to be 92.86% and 93.33%, respectively.

CONCLUSIONS:

The density of enlarged perivascular spaces was found to be significantly higher in those with mild cognitive impairment compared with age-matched healthy control subjects. The density of enlarged perivascular spaces, therefore, may be a useful imaging biomarker for the diagnosis of mild cognitive impairment.

Adjunctive Efficacy of Intra-Arterial Conebeam CT Angiography Relative to DSA in the Diagnosis and Surgical Planning of Micro-Arteriovenous Malformations [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

Micro-arteriovenous malformations are an underrecognized etiology of intracranial hemorrhage. Our study aimed to assess the adjunctive efficacy of intra-arterial conebeam CTA relative to DSA in the diagnosis and surgical planning of intracranial micro-AVMs.

MATERIALS AND METHODS:

We performed a retrospective study of all micro-AVMs (≤1-cm nidus) at our institution. Blinded neuroradiologists qualitatively graded DSA and intra-arterial conebeam CTA images for the detection of specific micro-AVM anatomic parameters (arterial feeder, micronidus, and venous drainer) and defined an overall diagnostic value. Statistical and absolute differences in the overall diagnostic values defined the relative intra-arterial conebeam CTA diagnostic values, respectively. Blinded neurosurgeons reported their treatment approach after DSA and graded the adjunctive value of intra-arterial conebeam CTA to improve or modify treatment. Intra-arterial conebeam CTA efficacy was defined as interobserver agreement in the relative intra-arterial conebeam CTA diagnostic and/or treatment-planning value scores.

RESULTS:

Ten patients with micro-AVMs presented with neurologic deficits and/or intracranial hemorrhages. Both neuroradiologists assigned a higher overall intra-arterial conebeam CTA diagnostic value (P < .05), secondary to improved evaluation of both arterial feeders and the micronidus, with good interobserver agreement ( = 0.66, P = .018) in the relative intra-arterial conebeam CTA diagnostic value. Both neurosurgeons reported that integrating the intra-arterial conebeam CTA data into their treatment plan would allow more confident localization for surgical/radiation treatment (8/10; altering the treatment plan in 1 patient), with good interobserver agreement in the relative intra-arterial conebeam CTA treatment planning value ( = 0.73, P = .025).

CONCLUSIONS:

Adjunctive intra-arterial conebeam CTA techniques are more effective in the diagnostic identification and anatomic delineation of micro-AVMs, relative to DSA alone, with the potential to improve microsurgical or radiosurgery treatment planning.

Investigation of a New Version of the Liquid Embolic Agent PHIL with Extra-Low-Viscosity in an Endovascular Embolization Model [INTERVENTIONAL]

BACKGROUND AND PURPOSE:

The type and composition of an embolic agent have a relevant influence on the performance of endovascular embolization. The aim of this study was to investigate a new version of the liquid embolic agent precipitating hydrophobic injectable liquid (PHIL) with extra-low-viscosity in an in vivo embolization model.

MATERIALS AND METHODS:

Twenty-four embolization procedures were performed in the porcine rete mirabile. Eight embolizations were performed with PHIL 25% low viscosity, Squid 12, and standard PHIL 25%, respectively. Procedure time, required volume of embolic agent, visibility of the embolic agent, embolization control, embolization extent (ie, penetration of the rete mirabile), amount of reflux, and degree of embolization distal to the rete mirabile were assessed.

RESULTS:

All embolic agents were adequately visible. The embolization extent was not significantly different among the 3 investigated agents; however, there was a tendency toward a higher embolization extent for PHIL 25% low viscosity (median embolization extent: 88% [PHIL 25% low viscosity]; 65% [Squid 12]; 60% [PHIL 25%]; P = .146). The amount of reflux was significantly lower for the extra-low-viscosity agents PHIL 25% low viscosity and Squid 12 compared with the standard PHIL 25% (median reflux distance: 8 mm [PHIL 25% low viscosity]; 6 mm [Squid 12]; 17 mm [PHIL 25%]; P = .011). All other embolization features did not differ among agents.

CONCLUSIONS:

PHIL 25% low viscosity is a promising liquid embolic agent for endovascular embolization, featuring effective distal penetration, adequate visibility, a low amount of reflux, and good flow control.

Brachial Plexus Ultrasound and MRI in Children with Brachial Plexus Birth Injury [PEDIATRICS]

BACKGROUND AND PURPOSE:

Brachial plexus birth injury is caused by traction on the neck during delivery and results in flaccid palsy of an upper extremity commonly involving C5–C6 nerve roots. MR imaging and MR myelography help to assess the anatomic location, extent, and severity of brachial plexus injuries which influence the long-term prognosis along with the surgical decision making. Recently, sonography has been increasingly used as the imaging modality of choice for brachial plexus injuries. The aim of this study was to assess the degree of correlation among brachial plexus sonography, MR imaging, and surgical findings in children with brachial plexus birth injury.

MATERIALS AND METHODS:

This prospective study included 55 consecutive patients (girls/boys = 32:23; mean age, 2.1 ± 0.8 months) with brachial plexus birth injury between May 2014 and April 2017. The patients were classified according to the Narakas classification and were followed up at 4- to 6-week intervals for recovery by the Modified Mallet system and sonography without specific preparation for evaluation. All patients had MR imaging under general anesthesia. Nerve root avulsion-retraction, pseudomeningocele, and periscalene soft tissue were accepted brachial plexus injury findings on imaging. Interobserver agreement for MR imaging and the agreement between imaging and surgical findings were estimated using the statistic. The diagnostic accuracy of sonography and MR imaging was calculated on the basis of the standard reference, which was the surgical findings.

RESULTS:

Forty-three patients had pre- and postganglionic injury, 12 had only postganglionic injury findings, and 47% of patients underwent an operation. On sonography, no patients had preganglionic injury, but all patients had postganglionic injury findings. For postganglionic injury, the concordance rates between imaging and the surgical findings ranged from 84% to 100%, and the diagnostic accuracy of sonography and MR imaging was 89% and 100%, respectively. For preganglionic injury, the diagnostic accuracy of MR imaging was 92%. Interobserver agreement and the agreement between imaging and the surgical findings were almost perfect for postganglionic injury ( = 0.81–1, P < .001).

CONCLUSIONS:

High-resolution sonography can identify and locate the postganglionic injury associated with the upper and middle trunks. The ability of sonography to evaluate pre- and the postganglionic injury associated with the lower trunk was quite limited. Sonography can be used as a complement to MR imaging; thus, the duration of the MR imaging examination and the need for sedation can be reduced by sonography.

Gadolinium Deposition within the Pediatric Brain: No Increased Intrinsic T1-Weighted Signal Intensity within the Dentate Nucleus following the Administration of a Minimum of 4 Doses of the Macrocyclic Agent Gadoteridol [PEDIATRICS]

BACKGROUND AND PURPOSE:

Our aim was to evaluate whether serial administration of the macrocyclic gadolinium-based contrast agent gadoteridol in children is associated with T1-weighted hyperintensity within the dentate nucleus, an imaging surrogate for gadolinium deposition.

MATERIALS AND METHODS:

We identified a retrospective cohort of 10 patients younger than 18 years of age who underwent between 4 and 8 gadoteridol-enhanced MR imaging examinations of the brain from 2016 to 2017. For comparison, we identified a retrospective cohort of 9 pediatric patients who each underwent 6 gadodiamide-enhanced MR imaging examinations. For each examination, both dentate nuclei were contoured on unenhanced images and the mean dentate-to-pons signal intensity ratio was calculated. Dentate-to-pons signal intensity ratios from the first and last scans were compared using paired t tests.

RESULTS:

In the gadoteridol group, there was no significant change in the mean dentate-to-pons signal intensity ratio from the first to the last scan (0.99 versus 0.99, P = .59). In the gadodiamide group, there was a significant increase in the mean dentate-to-pons signal intensity ratio from the first to the last scan (0.99 versus 1.10, P = .001).

CONCLUSIONS:

Repeat administration of the macrocyclic gadolinium-based contrast agent gadoteridol in children was not associated with T1-weighted dentate hyperintensity, while the repeat administration of the linear gadolinium-based contrast agent gadodiamide was associated with T1-weighted dentate hyperintensity, presumably due to gadolinium deposition.

Comparison of a Photon-Counting-Detector CT with an Energy-Integrating-Detector CT for Temporal Bone Imaging: A Cadaveric Study [HEAD & NECK]

BACKGROUND AND PURPOSE:

Evaluating abnormalities of the temporal bone requires high-spatial-resolution CT imaging. Our aim was to assess the performance of photon-counting-detector ultra-high-resolution acquisitions for temporal bone imaging and compare the results with those of energy-integrating-detector ultra-high-resolution acquisitions.

MATERIALS AND METHODS:

Phantom studies were conducted to quantify spatial resolution of the ultra-high-resolution mode on a prototype photon-counting-detector CT scanner and an energy-integrating-detector CT scanner that uses a comb filter. Ten cadaveric temporal bones were scanned on both systems with the radiation dose matched to that of the clinical examinations. Images were reconstructed using a sharp kernel, 0.6-mm (minimum) thickness for energy-integrating-detector CT, and 0.6- and 0.25-mm (minimum) thicknesses for photon-counting-detector CT. Image noise was measured and compared using adjusted 1-way ANOVA. Images were reviewed blindly by 3 neuroradiologists to assess the incudomallear joint, stapes footplate, modiolus, and overall image quality. The ranking results for each specimen and protocol were compared using the Friedman test. The Krippendorff α was used for interreader agreement.

RESULTS:

Photon-counting-detector CT showed an increase of in-plane resolution compared with energy-integrating-detector CT. At the same thickness (0.6 mm), images from photon-counting-detector CT had significantly lower (P < .001) image noise compared with energy-integrating-detector CT. Readers preferred the photon-counting-detector CT images to the energy-integrating-detector images for all 3 temporal bone structures. A moderate interreader agreement was observed with the Krippendorff α = 0.50. For overall image quality, photon-counting-detector CT image sets were ranked significantly higher than images from energy-integrating-detector CT (P < .001).

CONCLUSIONS:

This study demonstrated substantially better delineation of fine anatomy for the temporal bones scanned with the ultra-high-resolution mode of photon-counting-detector CT compared with the ultra-high-resolution mode of a commercial energy-integrating-detector CT scanner.

Organ transplant recipients express enhanced skin autofluorescence and pigmentation at skin cancer sites

Publication date: Available online 9 August 2018

Source: Journal of Photochemistry and Photobiology B: Biology

Author(s): Katrine Togsverd-Bo, Peter Alshede Philipsen, Merete Haedersdal, Hans Christian Wulf

Abstract

Background

Skin autofluorescence and pigmentation can estimate photodamage and sun exposure. These techniques may quantify differences in actinic damage between high-risk organ transplant recipients (OTRs) and immunocompetent patients.

Methods

Age and gender-matched OTRs (n = 15) and immunocompetent controls (n = 15) with a new keratinocyte carcinoma (KC) were included. We measured skin autofluorescence (370 nm excitation, F370) and skin pigmentation at five standardized body sites; and determined black light-evaluated solar lentigines on the shoulders and photosensitivity to UVA and simulated solar radiation (SSR) as minimal erythema doses (MED).

Results

F370 autofluorescence values were enhanced at KC site versus other body sites in OTRs (2208 vs. 1458–1898 AU, p < 0.05). Compared with non-OTRs, OTRs expressed higher F370 autofluorescence at KC site (2208 vs. 1385 arbitrary units AU, p = 0.01) and the shoulder (1898 vs. 1525, p = 0.05). Likewise, OTRs had increased skin pigmentation (25.0 vs. 20.8 pigment%, p = 0.05) and solar lentigines (3.5 vs. 3.0, p = 0.048) on the shoulders. MED tests showed increased UVA photosensitivity in OTRs (2.4 vs. 1.7 times higher than expected, p = 0.03), whereas SSR photosensitivity was similar.

Conclusion

Quantified F370 autofluorescence, skin pigmentation, and density of solar lentigines could serve to assess photodamage in OTR. Increased UVA photosensitivity may account for higher skin photodamage.

Tracing the sources of suspended sediment and particle-bound trace metal elements in an urban catchment coupling elemental and isotopic geochemistry, and fallout radionuclides

Abstract

The excessive supply of contaminants from urban areas to rivers during the last centuries has led to deleterious impacts on aquatic ecosystems. The sources, the behavior, and the dynamics of these contaminants must be better understood in order to reduce this excessive anthropogenic pollution. Accordingly, the current research investigated the particle-bound trace element (TE) contamination of the 900-km² Orge River (Seine basin, France) and the potential sources of these particles (agricultural or forest soils, channel banks, road deposited sediments), through the analysis of multiple fallout radionuclides, elemental geochemistry, and lead isotopic composition on suspended particulate matter (SPM) collected during a hydrological year at four stations following an increasing urbanization gradient (300 to 5000 inhab.km⁻²). Fallout radionuclide measurements showed an increasing contribution of recently eroded particles from urban areas to the SPM in downstream direction. However, this contribution varied depending on hydrological conditions. A greater contribution of particles originating from urban areas was observed during low stage periods. On the contrary, the contribution of agricultural soils and channel banks that are less enriched in contaminants and fallout radionuclides was higher during seasonal floods, which explained the dilution of radionuclide contents in sediment transiting the river during those events. Trace element contamination of SPM in Cu, Zn, Pb, and Sb increased from moderate to significant levels with urban pressure in downstream direction (with corresponding enrichment factors raising from 2 to 6). In addition, Pb isotopic ratios indicated that the main source of Pb corresponded to the "urban" signature found in road deposited sediments. The low variations in lead isotope ratios found in the SPM for contrasting hydrological conditions demonstrated the occurrence of a single source of Pb contamination. These results demonstrate the need to better manage urban runoff during both flood and low precipitation events to prevent the supply of diffuse particle-bound contamination to rivers draining urban areas.