Spatial single cell profiling using imaging mass cytometry - inflammatory versus penetrating Crohn's disease

BACKGROUND AND AIMS

Fistula formation is a major complication in Crohn's disease (CD) and the role of the immune cell compartment remains to be elucidated. Thus, we compared the immune-cell compartment of CD fistula to inflammatory CD colitis using imaging mass cytometry and immunofluorescence.

METHODS

A 36-marker panel including structural, functional and lineage markers for use in imaging mass cytometry (IMC) was established. This panel was applied to analyze paraffin-embedded CD fistula tract (n=11), CD colitis (n=10), and colon samples from non-inflamed controls (n=12). Computational methods for cell segmentation, dimensionality reduction and cell type clustering were used to define cell populations for cell frequency, marker distribution and spatial neighborhood analysis. Multiplex immunofluorescence was used for higher resolution spatial analysis.

RESULTS

Analysis of cell frequencies in CD fistulas compared to CD colitis and control colonic samples revealed a significant increase in neutrophils, effector cytotoxic T cells and inflammatory macrophages in CD fistula samples, whereas regulatory T cells were decreased. Neutrophils in CD fistula expressed significantly more matrix metalloproteinase 9 (MMP9), correlating to extracellular matrix remodeling. Neighborhood analysis revealed a strong association between MMP9+ neutrophils and effector cytotoxic T cells in both CD fistulas and colitis.

CONCLUSIONS

This study presents the first highly multiplexed single cell analysis of the immune-cell compartment of CD fistulas and their spatial context. It links immune cell dynamics, particularly MMP9+ neutrophils, to extracellular matrix remodeling in CD fistulas, offering insights into the complex network of cellular interactions and potential therapeutic targets for CD complications.

Activation of gp130 signaling in T cells drives TH17-mediated multi-organ autoimmunity

The IL-6-gp130-STAT3 signaling axis is a major regulator of inflammation. Activating mutations in the gene encoding gp130 and germline gain-of-function mutations in STAT3 (STAT3GOF) are associated with multi-organ autoimmunity, severe morbidity, and adverse prognosis. To dissect crucial cellular subsets and disease biology involved in activated gp130 signaling, the gp130-JAK-STAT3 axis was constitutively activated using a transgene, L-gp130, specifically targeted to T cells. Activating gp130 signaling in T cells in vivo resulted in fatal, early onset, multi-organ autoimmunity in mice that resembled human STAT3GOF disease. Female mice had more rapid disease progression than male mice. On a cellular level, gp130 signaling induced the activation and effector cell differentiation of T cells, promoted the expansion of T helper type 17 (TH17) cells, and impaired the activity of regulatory T cells. Transcriptomic profiling of CD4+ and CD8+ T cells from these mice revealed commonly dysregulated genes and a gene signature that, when applied to human transcriptomic data, improved the segregation of patients with transcriptionally diverse STAT3GOF mutations from healthy controls. The findings demonstrate that increased gp130-STAT3 signaling leads to TH17-driven autoimmunity that phenotypically resembles human STAT3GOF disease.

Maxillary canine position of patients with non-syndromic craniofacial disorder: a retrospective evaluation of panoramic radiographs

BACKGROUND

The study evaluates the position and displacement tendency of unerupted maxillary canines in orthodontic patients with non-syndromic craniofacial disorders (CD) compared to a control (C) group.

METHODS

Canine position and displacement tendency were evaluated using panoramic radiographs (PAN) examined with parameters such as sector classification (sectors 1-5) and inclination angles (α and β). The displacement tendency was defined as the positioning of the tip in sectors 1 or 2, as well as its combination with increased angles (α > 30° and β > 39°). In addition, the correlation of the tooth position and agenesis, cleft side, and sex was assessed.

RESULTS

A total of 116 pre-treatment PAN, divided into the CD group (n = 50; mean age 8.32 ± 2.27 years) and the C group (n = 66; mean age 10.80 ± 2.82 years), were evaluated in this study. The sector classification showed no displacement tendency in both groups. Inclination angles α/β showed a statistically significant higher displacement tendency (p = 0.01) of the CD group (n = 5) on the right side, compared to healthy subjects (n = 1). Male CD patients had a statistically significant higher displacement tendency on the right side (p = 0.03). A statistically significant correlation between cleft and non-cleft-side (p = 0.03) was found.

CONCLUSION

Patients with CD showed a statistically significant higher displacement tendency of the maxillary canine affected by the cleft side. The inclination angle was found to be the better predictor compared to the sector classification which should be considered in the orthodontic treatment planning.

Combined chemotherapy and pembrolizumab salvages multi-chemotherapy agent and avelumab resistant choriocarcinoma: A case report

Introduction

Gestational trophoblastic neoplasia (GTN) including choriocarcinoma (CC) frequently requires multi-agent chemotherapy to achieve cure. In chemotherapy-resistant GTN, immunotherapy with the checkpoint inhibitors pembrolizumab, avelumab and camrelizumab are potential new treatment options previously described in small case series, phase 2 trials and case reports.

Case description

A 32-year-old woman was diagnosed with gestational choriocarcinoma (FIGO score 5). Prior administered therapy regimes included methotrexate, actinomycin-D followed by open hysterectomy with bilateral salpingectomy (histology without GTN) as well as multi-agent chemotherapy and avelumab single-agent. After detection of a suspicious pulmonary mass video- assisted thoracoscopic left lung segmentectomy was performed confirming CC. The patient experienced an intracerebral haemorrhage and was treated with an emergency decompressive craniotomy. The cerebrospinal fluid showed an increased ratio of hCG compared to serum. Therapy with combined escalated etoposide and cisplatin with pembrolizumab was commenced followed by maintenance pembrolizumab achieving a complete hCG response and negative PET CT.

Discussion

In the management of multi drug- resistant GTN, application of checkpoint inhibitor pembrolizumab is a new therapeutic strategy. In this heavily pre-treated patient incorporation of pembrolizumab resulted in complete long-term response in a patient who had also failed avelumab therapy.

[Topicality of the fundamental and determining importance of chronic critical ischemia of the extremities and its restorative treatment using crural/pedal bypasses in Germany and in Saxony-Anhalt]

INTRODUCTION

Currently, there is an increase in severe stages of peripheral arterial occlusive disease (PAOD) with critical ischemia. This seems to correspond to the general demographic change as well as a consequence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic of the last 3 years. The now established and accepted interventional/endovascular approach for severe lower leg PAOD in experienced hands is still considered the first-line treatment but from the authors' perspective crural/pedal venous bypass is experiencing a renaissance.

MATERIAL AND METHODS

Compact narrative review of the current state of crural/pedal bypass surgery in Germany and Saxony-Anhalt (SA) combined with selective references from the current scientific medical literature and own clinical experiences.

RESULTS

The current statistics of case-related diagnosis-related groups (DRG) data show that, especially with the occurrence of the corona pandemic, a decrease in inpatient case numbers of patients with PAOD stage IIB can be observed nationwide and also in SA. The severe PAOD stages have remained approximately the same in case numbers but increased in SA. The risk stratification based on the wound, ischemia and foot infection (WIFI) classification offers the possibility to be able to make statements about the risk of amputation, benefits and type of revascularization measures. The length of the occlusion, occlusion site of the affected vessels and degree of calcification are taken into account in the global limb anatomic staging system (GLASS) to assess the prognosis. The evaluation of the case-based hospital statistics from 2015 to 2020 showed a constant use of femorocrural/femoropedal bypass surgery in Germany as well as a slight increase in reconstruction using femorocrural bypasses in SA, which seems to correlate with the tendency for an increase in the number of cases of severe PAOD. Parameter-based objectification of the severity of critical limb ischemia should be included in the indications for placement of a crural/pedal bypass. The WIFI classification and GLASS are suitable for this purpose as a relative prognosis of success is also possible. The treatment of critical limb ischemia by crural/pedal bypass surgery continues to find a constant application in Germany and SA.

[Statutory provisions, aims, motives, attitudes and thinking on the outpatient operation profile of general and abdominal surgery]

AIM

The aim of the manuscript is to discuss and assess the implications and opportunities as well as dangers of "outpatientization" of surgical and inpatient services for general and abdominal surgery.

METHOD

Narrative overview with literature reference based on a PubMed search with the search terms: outpatient operations and inpatient interventions, AOP catalog, hybrid DRG, outpatient hernia surgery, outpatient proctological surgery, selective sector-equal reimbursement and day-care forms of care. RESULTS (KEY POINTS): - In the Anglo-American area, the treatment of inguinal hernias is predominantly carried out on an outpatient clinic basis. In the USA, Sweden and Denmark, for example, over 70% of all hernias are treated in an outpatient clinic setting, in Germany it is only 20%. In Germany, the catalog of operations that can be performed on an outpatient basis and other department-replacing interventions in hospitals defines outpatient interventions in accordance with § 115b Social Security Code (SGB) V (Germany). - The conversion from inpatient to outpatient hernia surgery has also failed so far due to an enormous difference in revenues. According to the will of the Federal Ministry of Health, the planned forms of semistationary care are intended to relieve the nursing staff in the hospitals and thus relieve the tense situation of nursing professionals. By the end of March 2023, a special industry-specific reimbursement, so-called hybrid DRGs, is to be agreed, which applies regardless of whether a paid service is provided on an outpatient or inpatient basis. - According to § 115b SGB V, whether a hernia can be performed under inpatient or outpatient conditions is also decided according to the location of the hernia. In the new AOP catalog, frailty is operationalized in the context factors via the degree of care and the Barthel index. If one compares the number of encryption procedures for the 5‑530 procedure (closure of an inguinal hernia) in 2005 (184,679) with the pre-corona year 2019 (179,851), it can be seen that the proportion of hernias treated in hospital remained approximately the same over a period of 14 years. - Most elective proctological procedures can be performed on an outpatient basis. For reasons of safety (bleeding) and practicality (pain management, dressing change of large abscesses), inpatient surgery is preferred: extensive hemorrhoidectomy in the case of massive findings, large abscesses, extensive perianal fistula corrections, particularly high transsphincteric or suprasphincteric fistulas. - Guidelines based on the British Guidelines for Ambulant Surgery should be required for comprehensive outpatient treatment in surgery. The introduction of corresponding hybrid DRGs seems to be the right way to cover the costs of outpatient surgery in hospitals.

CONCLUSION

The restructuring of the hospital landscape and the nationwide expansion of outpatient operations is an unavoidable requirement in view of rising costs in the healthcare system and impending financing bottlenecks, which will pose challenges for the surgical disciplines in the years to come. Outpatient surgery is already practiced in many areas but has not become established due to the different remuneration. The flat rates for the same branches can be a starting point here. Furthermore, evidence-based framework conditions must be created along the lines of the British Guidelines for Ambulant Surgery.

Universal DNA methylation age across mammalian tissues

Aging, often considered a result of random cellular damage, can be accurately estimated using DNA methylation profiles, the foundation of pan-tissue epigenetic clocks. Here, we demonstrate the development of universal pan-mammalian clocks, using 11,754 methylation arrays from our Mammalian Methylation Consortium, which encompass 59 tissue types across 185 mammalian species. These predictive models estimate mammalian tissue age with high accuracy (r > 0.96). Age deviations correlate with human mortality risk, mouse somatotropic axis mutations and caloric restriction. We identified specific cytosines with methylation levels that change with age across numerous species. These sites, highly enriched in polycomb repressive complex 2-binding locations, are near genes implicated in mammalian development, cancer, obesity and longevity. Our findings offer new evidence suggesting that aging is evolutionarily conserved and intertwined with developmental processes across all mammals.

Photosensitisation and green egg yolks in laying hens caused by the feeding of ensiled alfalfa leaves

1. The present study was carried out to determine the effects of feeding ensiled alfalfa leaves (ALS) as an alternative protein source to laying hens under the terms of an organic diet. Due to the occurrence of unexpected negative health effects and undesirable egg yolk pigmentation in the test groups the trial was prematurely stopped and further analysis was conducted to evaluate the responsible substances.2. Body weights of the test groups decreased significantly already in week 2 of the trial. Performance variables dropped. Olive green pigmented egg yolks were found in groups fed diets containing ALS. Severe comb necrosis occurred in the experimental group receiving the highest level of ALS (20%) combined with the option of free-range access and therefore natural light exposure.3. The noxious agent found in ALS, blood serum and egg yolk was the photosensitising chlorophyll derivate pheophorbid a (PPBa), deriving from a strong depletion of chlorophyll contained in the alfalfa leaves. PPBa caused the olive-green pigmentation found in yolks and led to photosensitivity in groups with the highest level of ALS in the diet in combination with light exposure.4. By aiming for high protein and amino acid levels, harvesting and processing have, unintentionally and initially unnoticed, led to a strong accumulation of phototoxic PPBa. From these results it is strongly advised not to include ensiled alfalfa leaves as a protein source in organic laying hen diets.

Visualization of Inflammation in Experimental Colitis by Magnetic Resonance Imaging Using Very Small Superparamagnetic Iron Oxide Particles

Inflammatory bowel diseases (IBD) comprise mainly ulcerative colitis (UC) and Crohn´s disease (CD). Both forms present with a chronic inflammation of the (gastro) intestinal tract, which induces excessive changes in the composition of the associated extracellular matrix (ECM). In UC, the inflammation is limited to the colon, whereas it can occur throughout the entire gastrointestinal tract in CD. Tools for early diagnosis of IBD are still very limited and highly invasive and measures for standardized evaluation of structural changes are scarce. To investigate an efficient non-invasive way of diagnosing intestinal inflammation and early changes of the ECM, very small superparamagnetic iron oxide nanoparticles (VSOPs) in magnetic resonance imaging (MRI) were applied in two mouse models of experimental colitis: the dextran sulfate sodium (DSS)-induced colitis and the transfer model of colitis. For further validation of ECM changes and inflammation, tissue sections were analyzed by immunohistochemistry. For in depth ex-vivo investigation of VSOPs localization within the tissue, Europium-doped VSOPs served to visualize the contrast agent by imaging mass cytometry (IMC). VSOPs accumulation in the inflamed colon wall of DSS-induced colitis mice was visualized in T₂* weighted MRI scans. Components of the ECM, especially the hyaluronic acid content, were found to influence VSOPs binding. Using IMC, co-localization of VSOPs with macrophages and endothelial cells in colon tissue was shown. In contrast to the DSS model, colonic inflammation could not be visualized with VSOP-enhanced MRI in transfer colitis. VSOPs present a potential contrast agent for contrast-enhanced MRI to detect intestinal inflammation in mice at an early stage and in a less invasive manner depending on hyaluronic acid content.

Tooth agenesis in German orthodontic patients with non-syndromic craniofacial disorder: a retrospective evaluation of panoramic radiographs

Objectives

The study objective was to evaluate the tooth agenesis in German orthodontic patients with non-syndromic cleft lip and/or palate and Robin sequence compared to a control group without craniofacial disorder.

Materials/methods

A total of 108 panoramic radiographs were examined using the binary system of Tooth Agenesis Code (TAC) (excluding the third molar). Patients were divided into the craniofacial disorder group 1 (n = 43) and the healthy control group 2 (n = 65). Parameters such as skeletal class malformation, sex, localization of the cleft, craniofacial disorder, and interobserver reliability were assessed.

Results

Permanent tooth agenesis was observed in 44% of group 1 and 14% in group 2 with a statistically significant higher prevalence (p = 0.00162 (χ²)). Fourteen different TAC patterns were observed in group 1, ten of these occurring only once in separate patients. The distribution of the TAC codes in group 2 showed nine different possibilities of TAC code patterns; seven TACs were unique. In group 1, the most frequently absent teeth were the maxillary lateral incisor of the left side (30%); in group 2, the second premolar of the lower jaw on the right side (9%). Male patients with craniofacial disorder showed a higher percentage of tooth agenesis than female.

Conclusion

The data presented here shows a statistically significant higher prevalence of tooth agenesis in German patients with non-syndromic craniofacial disorder.

Clinical relevance

Radiographic evaluation enables the diagnosis of tooth agenesis. Recognizing early on the higher prevalence of tooth agenesis in patients exhibiting a craniofacial disorder is an important issue when developing long-term and comprehensive interdisciplinary treatment.

Human small intestinal infection by SARS-CoV-2 is characterized by a mucosal infiltration with activated CD8+ T cells

The SARS-CoV-2 pandemic has so far claimed over three and a half million lives worldwide. Though the SARS-CoV-2 mediated disease COVID-19 has first been characterized by an infection of the upper airways and the lung, recent evidence suggests a complex disease including gastrointestinal symptoms. Even if a direct viral tropism of intestinal cells has recently been demonstrated, it remains unclear, whether gastrointestinal symptoms are caused by direct infection of the gastrointestinal tract by SARS-CoV-2 or whether they are a consequence of a systemic immune activation and subsequent modulation of the mucosal immune system. To better understand the cause of intestinal symptoms we analyzed biopsies of the small intestine from SARS-CoV-2 infected individuals. Applying qRT-PCR and immunohistochemistry, we detected SARS-CoV-2 RNA and nucleocapsid protein in duodenal mucosa. In addition, applying imaging mass cytometry and immunohistochemistry, we identified histomorphological changes of the epithelium, which were characterized by an accumulation of activated intraepithelial CD8⁺ T cells as well as epithelial apoptosis and subsequent regenerative proliferation in the small intestine of COVID-19 patients. In summary, our findings indicate that intraepithelial CD8⁺ T cells are activated upon infection of intestinal epithelial cells with SARS-CoV-2, providing one possible explanation for gastrointestinal symptoms associated with COVID-19.

Produção leiteira de vacas em sistema semi-extensivo e sua relação com o estresse calórico

Considerando as caraterísticas subtropicais sul do Brasil, onde o verão é caracterizado por sua extensa duração com elevadas temperaturas e altos níveis de umidade, o estresse calórico é fator recorrente e pronunciado na bovinocultura leiteira. TTendo em vista o número expressivo de pequenos produtores e agricultura familiar na região de Santa Catarina, é imprescindível a análise dos impactos do estresse calórico em produções com menores dimensões. Por essas razões, o objetivo do presente estudo foi avaliar o impacto do estresse calórico na produção leiteira de vacas de baixa produção.11 animais foram analisados durante 4 meses (novembro a março), e as produções individuais diárias de leite foram obtidas através de copo coletor acoplado ao sistema de ordenha tipo espinha de peixe, com circuito fechado. Os dados das temperaturas diárias mínima e máxima, bem como a umidade relativa do ar durante o período experimental foram obtidos na estação meteorológica do Instituto Federal Catarinense Campus Araquari. As análises estatísticas foram realizadas com o auxílio do software SAS (versão 9.3, SAS Institute Inc., Cary, NC). Os dados foram submetidos a análise de variância (PROC MIXED) para avaliar o efeito do mês sobre o índice temperatura e umidade e a produção média de leite, e avaliar o efeito do ITU abaixo ou acima de 72 sobre a produção média de leite, além de correlação de Pearson (PROC CORR) e regressão (PROC REG) para avaliar a relação entre o ITU e a produção média de leite. As médias foram comparadas pelo teste de Tukey a 5% de probabilidade de erro. Os animais estudados não tiveram queda na produção quando o ITU foi mais pronunciado, sendo justificado pela baixa produção leiteira dos animais, tendo menor desafio metabólico.

Improvements in beam's eye view fiducial tracking using a novel multilayer imager

Purpose.Electronic portal image devices (EPIDs) have been investigated previously for beams-eye view (BEV) applications such as tumor tracking but are limited by low contrast-to-noise ratio and detective quantum efficiency. A novel multilayer imager (MLI), consisting of four stacked flat-panels was used to measure improvements in fiducial tracking during liver stereotactic body radiation therapy (SBRT) procedures compared to a single layer EPID.Methods.The prototype MLI was installed on a clinical TrueBeam linac in place of the conventional DMI single-layer EPID. The panel was extended during volumetric modulated arc therapy SBRT treatments in order to passively acquire data during therapy. Images were acquired for six patients receiving SBRT to liver metastases over two fractions each, one with the MLI using all 4 layers and one with the MLI using the top layer only, representing a standard EPID. The acquired frames were processed by a previously published tracking algorithm modified to identify implanted radiopaque fiducials. Truth data was determined using respiratory traces combined with partial manual tracking. Results for 4- and 1-layer mode were compared against truth data for tracking accuracy and efficiency. Tracking and noise improvements as a function of gantry angle were determined.Results. Tracking efficiency with 4-layers improved to 82.8% versus 58.4% for the 1-layer mode, a relative improvement of 41.7%. Fiducial tracking with 1-layer returned a root mean square error (RMSE) of 2.1 mm compared to 4-layer RMSE of 1.5 mm, a statistically significant (p < 0.001) improvement of 0.6 mm. The reduction in noise correlated with an increase in successfully tracked frames (r = 0.913) and with increased tracking accuracy (0.927).Conclusion. Increases in MV photon detection efficiency by utilization of a MLI results in improved fiducial tracking for liver SBRT treatments. Future clinical applications utilizing BEV imaging may be enhanced by including similar noise reduction strategies.

Olfactory transmucosal SARS-CoV-2 invasion as a port of central nervous system entry in individuals with COVID-19

The newly identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes COVID-19, a pandemic respiratory disease. Moreover, thromboembolic events throughout the body, including in the CNS, have been described. Given the neurological symptoms observed in a large majority of individuals with COVID-19, SARS-CoV-2 penetrance of the CNS is likely. By various means, we demonstrate the presence of SARS-CoV-2 RNA and protein in anatomically distinct regions of the nasopharynx and brain. Furthermore, we describe the morphological changes associated with infection such as thromboembolic ischemic infarction of the CNS and present evidence of SARS-CoV-2 neurotropism. SARS-CoV-2 can enter the nervous system by crossing the neural-mucosal interface in olfactory mucosa, exploiting the close vicinity of olfactory mucosal, endothelial and nervous tissue, including delicate olfactory and sensory nerve endings. Subsequently, SARS-CoV-2 appears to follow neuroanatomical structures, penetrating defined neuroanatomical areas including the primary respiratory and cardiovascular control center in the medulla oblongata.

Mutations in the splicing regulator Prp31 lead to retinal degeneration in Drosophila

Retinitis pigmentosa (RP) is a clinically heterogeneous disease affecting 1.6 million people worldwide. The second-largest group of genes causing autosomal dominant RP in human encodes regulators of the splicing machinery. Yet, how defects in splicing factor genes are linked to the aetiology of the disease remains largely elusive. To explore possible mechanisms underlying retinal degeneration caused by mutations in regulators of the splicing machinery, we induced mutations in Drosophila Prp31, the orthologue of human PRPF31, mutations in which are associated with RP11. Flies heterozygous mutant for Prp31 are viable and develop normal eyes and retina. However, photoreceptors degenerate under light stress, thus resembling the human disease phenotype. Degeneration is associated with increased accumulation of the visual pigment rhodopsin 1 and increased mRNA levels of twinfilin, a gene associated with rhodopsin trafficking. Reducing rhodopsin levels by raising animals in a carotenoid-free medium not only attenuates rhodopsin accumulation, but also retinal degeneration. Given a similar importance of proper rhodopsin trafficking for photoreceptor homeostasis in human, results obtained in flies presented here will also contribute to further unravel molecular mechanisms underlying the human disease.

This paper has an associated First Person interview with the co-first authors of the article.

Summary: Retinitis pigmentosa (RP) is a human disease resulting in blindness, which affects 1 in 4.000 people worldwide. So far >90 genes have been identified that are causally related to RP. Mutations in the splicing factor PRPF31 are linked to RP11. We induced mutations in the Drosophila orthologue Prp31 and show that flies heterozygous for Prp31 undergo light-dependent retinal degeneration. Degeneration is associated with increased accumulation of the light-sensitive molecule, rhodopsin 1. In fact, reducing rhodopsin levels by dietary intervention modifies the extent of retinal degeneration. This model will further contribute to better understand the aetiology of the human disease.

Clinical translation of a new flat-panel detector for beam's-eye-view imaging

Electronic portal imaging devices (EPIDs) lend themselves to beams-eye view clinical applications, such as tumor tracking, but are limited by low contrast and detective quantum efficiency (DQE). We characterize a novel EPID prototype consisting of multiple layers and investigate its suitability for use under clinical conditions. A prototype multi-layer imager (MLI) was constructed utilizing four conventional EPID layers, each consisting of a copper plate, a Gd2O2S:Tb phosphor scintillator, and an amorphous silicon flat panel array detector. We measured the detector's response to a 6 MV photon beam with regards to modulation transfer function, noise power spectrum, DQE, contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and the linearity of the detector's response to dose. Additionally, we compared MLI performance to the single top layer of the MLI and the standard Varian AS-1200 detector. Pre-clinical imaging was done on an anthropomorphic phantom, and the detector's CNR, SNR and spatial resolution were assessed in a clinical environment. Images obtained from spine and liver patient treatment deliveries were analyzed to verify CNR and SNR improvements. The MLI has a DQE(0) of 9.7%, about 5.7 times the reference AS-1200 detector. Improved noise performance largely drives the increase. CNR and SNR of clinical images improved three-fold compared to reference. A novel MLI was characterized and prepared for clinical translation. The MLI substantially improved DQE and CNR performance while maintaining the same resolution. Pre-clinical tests on an anthropomorphic phantom demonstrated improved performance as predicted theoretically. Preliminary patient data were analyzed, confirming improved CNR and SNR. Clinical applications are anticipated to include more accurate soft tissue tracking.

Research Note: Delay in sampling influences the profile of phytate in gizzard digesta and ileal digestibility of phosphorus in broilers

The objective of this study was to investigate the effect of different durations of time delay when sampling digesta from the gizzard and ileum of broilers on the degradation of myo-inositol hexakisphosphate (InsP₆) and digestibility of phosphorus (P). There was 1 experimental diet with a supplemental phytase activity of 1,212 phytase units/kg feed, which was provided to birds from day 13 to 18 after hatching. The diet was formulated to provide 6.6 g/kg Ca and 1.9 g/kg nonphytate P and fed to 24 cages of 6 birds. The 24 cages of birds were further randomly divided into 6 subgroups of 4 cages from which the digesta samples in the gizzard and ileum were collected at 0, 5, 10, or 20 min postmortem. The results showed that the concentration of InsP₆ decreased linearly (P = 0.002), InsP₅ decreased quadratically (P = 0.038), and the summation of concentrations of P in InsP_6-4 decreased linearly (P = 0.028) in the gizzard digesta with the increasing delay of sampling. In the ileum, the digestibility of phytate P tended to decrease linearly (P = 0.087), and the digestibility of total P decreased linearly (P = 0.026) with prolonged delay. In conclusion, delay in sampling could alter the measured profile of InsP esters in gizzard digesta probably because of a continued effect of supplemental phytase, while the ileal digestibility of total P could diminish. Therefore, standard sampling procedures should be implemented to minimize variance.

Automated MV markerless tumor tracking for VMAT

Tumor tracking during radiotherapy treatment can improve dose accuracy, conformity and sparing of healthy tissue. Many methods have been introduced to tackle this challenge utilizing multiple imaging modalities, including a template matching based approach using the megavoltage (MV) on-board portal imager demonstrated on 3D conformal treatments. However, the complexity of treatments is evolving with the introduction of VMAT and IMRT, and successful motion management is becoming more important due to a trend towards hypofractionation. We have developed a markerless lung tumor tracking algorithm, utilizing the electronic portal imager (EPID) of the treatment machine. The algorithm has been specifically adapted to track during complex treatment deliveries with gantry and MLC motion. The core of the algorithm is an adaptive template matching method that relies on template stability metrics and local relative orientations to perform multiple feature tracking simultaneously. Only a single image is required to initialize the algorithm and features are automatically added, modified or removed in response to the input images. This algorithm was evaluated against images collected during VMAT arcs of a dynamic thorax phantom. Dynamic phantom images were collected during radiation delivery for multiple lung SBRT breathing traces and an example patient data set. The tracking error was 1.34 mm for the phantom data and 0.68 mm for the patient data. A multi-region, markerless tracking algorithm has been developed, capable of tracking multiple features simultaneously without requiring any other a priori information. This novel approach delivers robust target localization during complex treatment delivery. The reported tracking error is similar to previous reports for 3D conformal treatments.

Concurrent Vogt-Koyanagi-Harada disease and impressive response to immune checkpoint blockade in metastatic melanoma

Background: Vogt-Koyanagi-Harada disease (VKHD)-like symptoms have previously been reported in 11 melanoma patients treated with immune checkpoint inhibitors. Materials & methods: We report a female patient with multilocular metastatic melanoma who was treated with nivolumab. Results: Following the first nivolumab dose, she experienced bilateral blurry vision, hearing loss, vertigo and ataxia. Ocular ultrasound was consistent with the diagnosis of uveitis. Audiography revealed severe bilateral sensorineural hearing loss. A high-dose corticosteroid regimen was initiated under which the patient developed generalized vitiligo. Abdominal and thoracic CT scans showed an almost complete response to nivolumab therapy. This patient fulfilled all criteria of VKHD which is characterized pathogenetically by an antimelanocytic autoimmune process. Conclusion: The present case showed an impressive response to antimelanoma immunotherapy. Based on these data, the occurrence of VKHD in melanoma patients appears to be a strong indicator for immune checkpoint inhibitor efficacy.

Dynamical diffraction effects on the geometric phase of inhomogeneous strain fields

In specimens with an inhomogeneous displacement field in electron beam direction dynamical diffraction effects lead to complex non-linear properties of the diffracted electron wave. Consequently, the diffracted beam's phase contains information about the inhomogeneous displacement field. These phases are experimentally and theoretically investigated under different excitation errors and specimen thicknesses as well as for different depths of the displacement field. An inclined InGaAs layer with a larger lattice constant than the surrounding GaAs matrix serves as controlled displacement field, which is inhomogeneous in electron beam direction with a continuously changing depth. The phase and amplitude of the diffracted beam are measured by dark-field electron holography. The measurements agree with calculations performed by numerical propagation of the electron wave using the Darwin-Howie-Whelan equations. A strong dependency on the excitation conditions is found showing that the interplay between dynamical effects and the strain field must be considered in the interpretation of the geometric phase.

Drosophila melanogaster: A Valuable Genetic Model Organism to Elucidate the Biology of Retinitis Pigmentosa

Retinitis pigmentosa (RP) is a complex inherited disease. It is associated with mutations in a wide variety of genes with many different functions. These mutations impact the integrity of rod photoreceptors and ultimately result in the progressive degeneration of rods and cone photoreceptors in the retina, leading to complete blindness. A hallmark of this disease is the variable degree to which symptoms are manifest in patients. This is indicative of the influence of the environment, and/or of the distinct genetic makeup of the individual.The fruit fly, Drosophila melanogaster, has effectively proven to be a great model system to better understand interconnected genetic networks. Unraveling genetic interactions and thereby different cellular processes is relatively easy because more than a century of research on flies has enabled the creation of sophisticated genetic tools to perturb gene function. A remarkable conservation of disease genes across evolution and the similarity of the general organization of the fly and vertebrate photoreceptor cell had prompted research on fly retinal degeneration. To date six fly models for RP, including RP4, RP11, RP12, RP14, RP25, and RP26, have been established, and have provided useful information on RP disease biology. In this chapter, an outline of approaches and experimental specifications are described to enable utilizing or developing new fly models of RP.

Coding of medically unexplained symptoms and somatoform disorders by general practitioners - an exploratory focus group study

BACKGROUND

Medically unexplained symptoms (MUS) and somatoform disorders are common in general practices, but there is evidence that general practitioners (GPs) rarely use these codes. Assuming that correct classification and coding of symptoms and diseases are important for adequate management and treatment, insights into these processes could reveal problematic areas and possible solutions. Our study aims at exploring general practitioners' views on coding and reasons for not coding MUS/somatoform disorders.

METHODS

We invited GPs to participate in six focus groups (N = 42). Patient vignettes and a semi-structured guideline were used by two moderators to facilitate the discussions. Recordings were transcribed verbatim. Two researchers analyzed the data using structuring content analysis with deductive and inductive category building.

RESULTS

Three main categories turned out to be most relevant. For category a) "benefits of coding" GPs described that coding is seen as being done for reimbursement purposes and is not necessarily linked to the content of their reference files for a specific patient. Others reported to code specific diagnoses only if longer consultations to explore psychosomatic symptoms or psychotherapy are intended to be billed. Reasons for b) "restrained coding" were attempting to protect the patient from stigma through certain diagnoses and the preference for tentative diagnoses and functional coding. Some GPs admitted to c) "code inaccurately" attributing this to insufficient knowledge of ICD-10-criteria, time constraints or using "rules of thumb" for coding.

CONCLUSIONS

There seem to be challenges in the process of coding of MUS and somatoform disorders, but GPs appear not to contest the patients' suffering and accept uncertainty (about diagnoses) as an elementary part of their work. From GPs' points of view ICD-10-coding does not appear to be a necessary requirement for treating patients and coding might be avoided to protect the patients from stigma and other negative consequences. Our findings supply a possible explanation for the commonly seen difference between routine and epidemiological data. The recent developments in the DSM-5 and the upcoming ICD-11 will supposedly change acceptance and handling of these diagnoses for GPs and patients. Either way, consequences for GPs' diagnosing and coding behavior are not yet foreseeable.

Modification of the triangulation technique for arthroscopy of the canine shoulder joint using a new target device

A modified triangulation technique for arthroscopy of the canine shoulder joint to insert a working cannula in the caudal joint pouch is described. This technique is compared with the triangulation technique of Van Ryssen (10). With the modified triangulation the insertion angle for the working cannula into the caudal joint pouch was provided by a target device which was attached to the arthroscopic sleeve. Both methods were carried out on 60 dog cadavers and the differences were recorded in terms of various parameters: success (SUC), time (TI), number of trials (TR), position of the working cannula (POS), damage to articular cartilage (DAM), and force to remove the working cannula (FOR). The modified triangulation technique permits simpler, faster and less traumatic insertion of the working cannula into the caudal joint pouch.

Prevalence, demographic variation and psychological correlates of exposure to police victimisation in four US cities

Aims Victimisation by the police is purported to be widespread in cities in the USA, but there is limited data on police-public encounters from community samples. This is partly due to an absence of measures for assessing police violence exposure from the standpoint of civilians. As such, the demographic distribution and mental health correlates of police victimisation are poorly understood. The aims of this study were to present community-based prevalence estimates of positive policing and police victimisation based on assessment with two novel measures, and to test the hypotheses that (1) exposure to police victimisation would vary across demographic groups and (2) would be associated with depression and psychological distress.

METHODS

The Survey of Police-Public Encounters study surveyed adults residing in four US cities to examine the prevalence, demographic distribution and psychological correlates of police victimisation. Participants (N = 1615) completed measures of psychological distress (K-6 scale), depression (Patient Health Questionnaire 9) and two newly constructed measures of civilian-reported police-public encounters. Both measures were developed to assess police victimisation based on the WHO domains of violence, which include physical violence (with and without a weapon, assessed separately), sexual violence (inappropriate sexual contact, including public strip searches), psychological violence (e.g., threatening, intimidating, stopping without cause, or using discriminatory slurs) and neglect (police not responding when called or responding too late). The Police Practices Inventory assesses lifetime history of exposure to positive policing and police victimisation, and the Expectations of Police Practices Scale assesses the perceived likelihood of future incidents of police victimisation. Linear regression models were used to test for associations between police-public encounters and psychological distress and depression.

RESULTS

Psychological violence (18.6%) and police neglect (18.8%) were commonly reported in this sample and a substantial minority of respondents also reported more severe forms of violence, specifically physical (6.1%), sexual (2.8%) and physical with a weapon (3.3%). Police victimisation was more frequently reported by racial/ethnic minorities, males, transgender respondents and younger adults. Nearly all forms of victimisation (but not positive policing) were associated with psychological distress and depression in adjusted linear regression models.

CONCLUSIONS

Victimisation by police appears to be widespread, inequitably distributed across demographic groups and psychologically impactful. These findings suggest that public health efforts to both reduce the prevalence of police violence and to alleviate its psychological impact may be needed, particularly in disadvantaged urban communities.

Electron holography on HfO2/HfO2-x bilayer structures with multilevel resistive switching properties

Unveiling the physical nature of the oxygen-deficient conductive filaments (CFs) that are responsible for the resistive switching of the HfO₂-based resistive random access memory (RRAM) devices represents a challenging task due to the oxygen vacancy related defect nature and nanometer size of the CFs. As a first important step to this goal, we demonstrate in this work direct visualization and a study of physico-chemical properties of oxygen-deficient amorphous HfO_2-x by carrying out transmission electron microscopy electron holography as well as energy dispersive x-ray spectroscopy on HfO₂/HfO_2-x bilayer heterostructures, which are realized by reactive molecular beam epitaxy. Furthermore, compared to single layer devices, Pt/HfO₂/HfO_2-x /TiN bilayer devices show enhanced resistive switching characteristics with multilevel behavior, indicating their potential as electronic synapses in future neuromorphic computing applications.

A microfluidic model of hemostasis sensitive to platelet function and coagulation

Hemostasis is the process of sealing a vascular injury with a thrombus to arrest bleeding. The type of thrombus that forms depends on the nature of the injury and hemodynamics. There are many models of intravascular thrombus formation whereby blood is exposed to prothrombotic molecules on a solid substrate. However, there are few models of extravascular thrombus formation whereby blood escapes into the extravascular space through a hole in the vessel wall. Here, we describe a microfluidic model of hemostasis that includes vascular, vessel wall, and extravascular compartments. Type I collagen and tissue factor, which support platelet adhesion and initiate coagulation, respectively, were adsorbed to the wall of the injury channel and act synergistically to yield a stable thrombus that stops blood loss into the extravascular compartment in ~7.5 min. Inhibiting factor VIII to mimic hemophilia A results in an unstable thrombus that was unable to close the injury. Treatment with a P2Y12 antagonist to reduce platelet activation prolonged the closure time two-fold compared to controls. Taken together, these data demonstrate a hemostatic model that is sensitive to both coagulation and platelet function and can be used to study coagulopathies and platelet dysfunction that result in excessive blood loss.

Evaluation of tubomanometry as a routine diagnostic tool for chronic obstructive Eustachian tube dysfunction

OBJECTIVE

The objective of this study was to demonstrate the reliability of tubomanometry (TMM) described by Estéve in the diagnosis of chronic obstructive Eustachian tube (ET) dysfunction.

STUDY DESIGN

Combined prospective and retrospective clinical study.

SETTING

Tertiary referral centre, affiliated to university.

METHODS

Two hundred and fifteen healthy subjects were examined once, 25 healthy subjects underwent TMM weekly for 6 weeks, and six healthy subjects were tested three times a day on at least three different days. The results of tubomanometry in healthy subjects were compared to data obtained from 171 patients with chronic obstructive ET dysfunction.

RESULTS

In healthy subjects, there was an immediate opening of the ET at 30-50 mbar with an R-value ≤ 1 in at least 94% of the cases. In patients with chronic ET dysfunction, an opening of the ET could be registered in only 42% of patients at 30 mbar and in 58% at 50 mbar. The average of the R-value in these subjects always indicated towards a delayed opening (R > 1). When measurements are repeated in the same subject with a weekly interval, the intraclass correlation (ICC) was 0.49 for the TMM with 30 mbar, 0.51 for the TMM with 40 mbar and 0.52 for the TMM with 50 mbar in healthy people. For the patients with symptoms of ET dysfunction, the ICC for up to four repeated measures was 0.50 for the TMM with 30 mbar, 0.53 for the TMM with 40 mbar and 0.54 for the TMM with 50 mbar. A complete agreement of the results in repeated measurements within seconds was present in 86% for 30 and 40 mbar and in 79% for 50 mbar. The ICC was 0.61 for the TMM with 50 mbar, 0.62 for the TMM with 40 mbar and 0.68 for the TMM with 30 mbar.

CONCLUSIONS

Tubomanometry can support the diagnosis of ET dysfunction. An R-value ≤ 1 indicates a regular function of the ET, an R-value >1 indicates a delayed opening of the ET, and no definable R-value means no detectable opening of the ET. TMM is a reliable and valid instrument to support the diagnosis of chronic obstructive ET dysfunction.

[Bacteriologic investigation of the Eustachian tube and the implications of perioperative antibiotics before balloon dilation]

BACKGROUND

Balloon Eustachian Tuboplasty (BET) is a new minimally invasive treatment for chronic Eustachian tube dysfunction (ETD). Initially, perioperative prophylactic antibiotic therapy with ciprofloxacin 2 × 500 mg p.o. for 5 days was administered. This study aimed to characterize the bacterial flora in the ET, nose, and pharynx in patients with chronic obstructive ETD. Additionally, we investigated the necessity of perioperative antibiotic prophylaxis in BET patients.

PATIENTS AND METHODS

We examined 40 patients undergoing BET: 20 patients with and 20 patients without perioperative antibiotic prophylaxis. All patients were followed-up for clinical signs and symptoms of local infection for at least 2 weeks after surgery. Following BET, the tips of 35 balloon catheters, as well as swabs from the nose and pharynx were sent for microbiologic analysis.

RESULTS

None of these 40 patients had postoperative signs of infection. Of the swabs of the balloon catheters, 46% were sterile and 23% showed standard flora. The remaining 31% of swaps revealed specific bacteria. However, none of the nasal or nasopharyngeal swaps were sterile.

CONCLUSION

Due to the lack of signs of postoperative infection in either investigated group, the authors no longer favor use of perioperative antibiotic prophylaxis in patients undergoing BET. The relevance of biofilms and pathogen colonization to ET function has recently been intensively discussed, and should be further investigated in future studies.

Hypoxia increases susceptibility of Pacific white shrimp to whitespot syndrome virus (WSSV)

The present study aimed to evaluate the mortality, reactive oxygen species production (ROS) and total hemocyte counts (THC) of the marine shrimp Litopenaeus vannamei infected with the white spot syndrome virus (WSSV) at three levels of oxygen saturation. For this, 360 shrimp (20±2g) were distributed in 24 tanks (60L), divided in two groups (infected and non-infected), which were subjected to 30, 60 and 100% of dissolved oxygen saturation (in quadruplicate). During 96 hours after infection, daily hemolymph samples were collected for hemato-immunological parameter evaluation (THC and ROS) and dead animals were removed and computed to assess cumulative mortality rates. In the infected group, animals subjected to 100% saturation showed higher ROS production (P<0.05) after 48 hours, while THC was significantly reduced (P<0.05), regardless of oxygen saturation. The hypoxia resulted in high mortality when compared to 100% saturation condition. In the uninfected group, no significant differences were observed in all evaluated parameters. Thus, the hypoxia condition increased the susceptibility of shrimp to the infection of WSSV, which may be partly related to the low ROS production showed by the animals subjected to 30% oxygen saturation.