Cyclin D-CDK4 Disulfide Bond Attenuates Pulmonary Vascular Cell Proliferation

BACKGROUND

Pulmonary hypertension (PH) is a chronic vascular disease characterized, among other abnormalities, by hyperproliferative smooth muscle cells and a perturbed cellular redox and metabolic balance. Oxidants induce cell cycle arrest to halt proliferation; however, little is known about the redox-regulated effector proteins that mediate these processes. Here, we report a novel kinase-inhibitory disulfide bond in cyclin D-CDK4 (cyclin-dependent kinase 4) and investigate its role in cell proliferation and PH.

METHODS

Oxidative modifications of cyclin D-CDK4 were detected in human pulmonary arterial smooth muscle cells and human pulmonary arterial endothelial cells. Site-directed mutagenesis, tandem mass-spectrometry, cell-based experiments, in vitro kinase activity assays, in silico structural modeling, and a novel redox-dead constitutive knock-in mouse were utilized to investigate the nature and definitively establish the importance of CDK4 cysteine modification in pulmonary vascular cell proliferation. Furthermore, the cyclin D-CDK4 oxidation was assessed in vivo in the pulmonary arteries and isolated human pulmonary arterial smooth muscle cells of patients with pulmonary arterial hypertension and in 3 preclinical models of PH.

RESULTS

Cyclin D-CDK4 forms a reversible oxidant-induced heterodimeric disulfide dimer between C7/8 and C135, respectively, in cells in vitro and in pulmonary arteries in vivo to inhibit cyclin D-CDK4 kinase activity, decrease Rb (retinoblastoma) protein phosphorylation, and induce cell cycle arrest. Mutation of CDK4 C135 causes a kinase-impaired phenotype, which decreases cell proliferation rate and alleviates disease phenotype in an experimental mouse PH model, suggesting this cysteine is indispensable for cyclin D-CDK4 kinase activity. Pulmonary arteries and human pulmonary arterial smooth muscle cells from patients with pulmonary arterial hypertension display a decreased level of CDK4 disulfide, consistent with CDK4 being hyperactive in human pulmonary arterial hypertension. Furthermore, auranofin treatment, which induces the cyclin D-CDK4 disulfide, attenuates disease severity in experimental PH models by mitigating pulmonary vascular remodeling.

CONCLUSIONS

A novel disulfide bond in cyclin D-CDK4 acts as a rapid switch to inhibit kinase activity and halt cell proliferation. This oxidative modification forms at a critical cysteine residue, which is unique to CDK4, offering the potential for the design of a selective covalent inhibitor predicted to be beneficial in PH.

Resilience to autosomal dominant Alzheimer's disease in a Reelin-COLBOS heterozygous man

We characterized the world's second case with ascertained extreme resilience to autosomal dominant Alzheimer's disease (ADAD). Side-by-side comparisons of this male case and the previously reported female case with ADAD homozygote for the APOE3 Christchurch (APOECh) variant allowed us to discern common features. The male remained cognitively intact until 67 years of age despite carrying a PSEN1-E280A mutation. Like the APOECh carrier, he had extremely elevated amyloid plaque burden and limited entorhinal Tau tangle burden. He did not carry the APOECh variant but was heterozygous for a rare variant in RELN (H3447R, termed COLBOS after the Colombia-Boston biomarker research study), a ligand that like apolipoprotein E binds to the VLDLr and APOEr2 receptors. RELN-COLBOS is a gain-of-function variant showing stronger ability to activate its canonical protein target Dab1 and reduce human Tau phosphorylation in a knockin mouse. A genetic variant in a case protected from ADAD suggests a role for RELN signaling in resilience to dementia.

Extracellular Matrix Profiling and Disease Modelling in Engineered Vascular Smooth Muscle Cell Tissues

Aortic smooth muscle cells (SMCs) have an intrinsic role in regulating vessel homeostasis and pathological remodelling. In two-dimensional (2D) cell culture formats, however, SMCs are not embedded in their physiological extracellular matrix (ECM) environment. To overcome the limitations of conventional 2D SMC cultures, we established a 3D in vitro model of engineered vascular smooth muscle cell tissues (EVTs). EVTs were casted from primary murine aortic SMCs by suspending a SMC-fibrin master mix between two flexible silicon-posts at day 0 before prolonged culture up to 14 days. Immunohistochemical analysis of EVT longitudinal sections demonstrated that SMCs were aligned, viable and secretory. Mass spectrometry-based proteomics analysis of murine EVT lysates was performed and identified 135 matrisome proteins. Proteoglycans, including the large aggregating proteoglycan versican, accumulated within EVTs by day 7 of culture. This was followed by the deposition of collagens, elastin-binding proteins and matrix regulators up to day 14 of culture. In contrast to 2D SMC controls, accumulation of versican occurred in parallel to an increase in versikine, a cleavage product mediated by proteases of the A Disintegrin and Metalloproteinase with Thrombospondin motifs (ADAMTS) family. Next, we tested the response of EVTs to stimulation with transforming growth factor beta-1 (TGFβ-1). EVTs contracted in response to TGFβ-1 stimulation with altered ECM composition. In contrast, treatment with the pharmacological activin-like kinase inhibitor (ALKi) SB 431542 suppressed ECM secretion. As a disease stimulus, we performed calcification assays. The ECM acts as a nidus for calcium phosphate deposition in the arterial wall. We compared the onset and extent of calcification in EVTs and 2D SMCs cultured under high calcium and phosphate conditions for 7 days. Calcified EVTs displayed increased tissue stiffness by up to 30 % compared to non-calcified controls. Unlike the rapid calcification of SMCs in 2D cultures, EVTs sustained expression of the calcification inhibitor matrix Gla protein and allowed for better discrimination of the calcification propensity between independent biological replicates. In summary, EVTs are an intuitive and versatile model to investigate ECM synthesis and turnover by SMCs in a 3D environment. Unlike conventional 2D cultures, EVTs provide a more relevant pathophysiological model for retention of the nascent ECM produced by SMCs.

Loss of Homeostatic Microglia Signature in Prion Diseases

Prion diseases are neurodegenerative diseases that affect humans and animals. They are always fatal and, to date, no treatment exists. The hallmark of prion disease pathophysiology is the misfolding of an endogenous protein, the cellular prion protein (PrP^C), into its disease-associated isoform PrP^Sc. Besides the aggregation and deposition of misfolded PrP^Sc, prion diseases are characterized by spongiform lesions and the activation of astrocytes and microglia. Microglia are the innate immune cells of the brain. Activated microglia and astrocytes represent a common pathological feature in neurodegenerative disorders. The role of activated microglia has already been studied in prion disease mouse models; however, it is still not fully clear how they contribute to disease progression. Moreover, the role of microglia in human prion diseases has not been thoroughly investigated thus far, and specific molecular pathways are still undetermined. Here, we review the current knowledge on the different roles of microglia in prion pathophysiology. We discuss microglia markers that are also dysregulated in other neurodegenerative diseases including microglia homeostasis markers. Data on murine and human brain tissues show that microglia are highly dysregulated in prion diseases. We highlight here that the loss of homeostatic markers may especially stand out.

CMYA5 is a novel interaction partner of FHL2 in cardiac myocytes

Four-and-a-half LIM domains protein 2 (FHL2) is an anti-hypertrophic adaptor protein that regulates cardiac myocyte signalling and function. Herein, we identified cardiomyopathy-associated 5 (CMYA5) as a novel FHL2 interaction partner in cardiac myocytes. In vitro pull-down assays demonstrated interaction between FHL2 and the N- and C-terminal regions of CMYA5. The interaction was verified in adult cardiac myocytes by proximity ligation assays. Immunofluorescence and confocal microscopy demonstrated co-localisation in the same subcellular compartment. The binding interface between FHL2 and CMYA5 was mapped by peptide arrays. Exposure of neonatal rat ventricular myocytes to a CMYA5 peptide covering one of the FHL2 interaction sites led to an increase in cell area at baseline, but a blunted response to chronic phenylephrine treatment. In contrast to wild-type hearts, loss or reduced FHL2 expression in Fhl2-targeted knockout mouse hearts or in a humanised mouse model of hypertrophic cardiomyopathy led to redistribution of CMYA5 into the perinuclear and intercalated disc region. Taken together, our results indicate a direct interaction of the two adaptor proteins FHL2 and CMYA5 in cardiac myocytes, which might impact subcellular compartmentation of CMYA5.

Mast cell‐deficient mice Mcpt5Cre/Dicer fl/fl redefine the role of mast cells in experimental bullous pemphigoid

Background

Bullous pemphigoid (BP) is the most frequent autoimmune blistering disease of the skin affecting the elderly. BP is immunopathologically characterized by autoantibodies against BP180 and BP230. With the growing evidence of cell‐mediated autoimmunity in the pathogenesis of BP, it still remains unclear whether mast cells (MCs) are involved, due to conflicting data obtained from Kit‐dependent MC‐deficient mouse models.

Objectives

To clarify the role of MCs in experimental BP; the dynamics in cutaneous MC numbers, associated immune cells and the development of disease in Kit‐independent MC‐deficient mouse model.

Methods

Employing a recently established murine adult passive transfer model of BP induced by the transfer of pathogenic immunoglobulin G (IgG), lesional skin biopsies were investigated histologically and immunohistochemically for the time‐dependent MC accumulation and dermal infiltration.

Results

The numbers of cutaneous MCs increased following the induction of BP, in part, maintained by MC proliferation. Numbers of T cells, neutrophils and eosinophils in the skin also increased after BP induction, with eosinophils showing a preferential co‐localization with MCs. Furthermore, clinical disease manifestation in MC‐deficient Mcpt5Cre/Dicer^fl/fl mice remained unchanged compared to MC‐sufficient Dicer^fl/fl mice. The composition of the immune cell infiltration including as T cells, neutrophils and eosinophils was largely unaffected by the absence of MCs.

Conclusion

MCs do not play a pivotal role in the pathogenesis of passive IgG‐transfer mediated BP model. Their increase in number may be a bystander effect following tissue injury. We therefore suggest caution regarding the selection of MCs as sole targets for the development of novel drugs for BP.

The blood-brain barrier is dysregulated in COVID-19 and serves as a CNS entry route for SARS-CoV-2

Neurological complications are common in COVID-19. Although SARS-CoV-2 has been detected in patients’ brain tissues, its entry routes and resulting consequences are not well understood. Here, we show a pronounced upregulation of interferon signaling pathways of the neurovascular unit in fatal COVID-19. By investigating the susceptibility of human induced pluripotent stem cell (hiPSC)-derived brain capillary endothelial-like cells (BCECs) to SARS-CoV-2 infection, we found that BCECs were infected and recapitulated transcriptional changes detected in vivo. While BCECs were not compromised in their paracellular tightness, we found SARS-CoV-2 in the basolateral compartment in transwell assays after apical infection, suggesting active replication and transcellular transport of virus across the blood-brain barrier (BBB) in vitro. Moreover, entry of SARS-CoV-2 into BCECs could be reduced by anti-spike-, anti-angiotensin-converting enzyme 2 (ACE2)-, and anti-neuropilin-1 (NRP1)-specific antibodies or the transmembrane protease serine subtype 2 (TMPRSS2) inhibitor nafamostat. Together, our data provide strong support for SARS-CoV-2 brain entry across the BBB resulting in increased interferon signaling.

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IFNγ signaling is upregulated in COVID-19 human neurovascular unit

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SARS-CoV-2-infected hiPS-BCECs display similar upregulation of IFNγ signaling

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SARS-CoV-2 replicates in hiPS-BCECs and is released while barrier remains intact

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SARS-CoV-2 infection of hiPS-BCECs is decreased by antibodies and protease inhibitors

Inoculation route-dependent Lassa virus dissemination and shedding dynamics in the natural reservoir - Mastomys natalensis

Lassa virus (LASV), a Risk Group-4 zoonotic haemorrhagic fever virus, affects sub-Saharan African countries. Lassa fever, caused by LASV, results in thousands of annual deaths. Although decades have elapsed since the identification of the Natal multimammate mouse (Mastomys natalensis) as a natural reservoir of LASV, little effort has been made to characterize LASV infection in its reservoir. The natural route of infection and transmission of LASV within M. natalensis remains unknown, and the clinical impact of LASV in M. natalensis is mostly undescribed. Herein, using an outbred colony of M. natalensis, we investigate the replication and dissemination dynamics of LASV in this reservoir following various inoculation routes. Inoculation with LASV, regardless of route, resulted in a systemic infection and accumulation of abundant LASV-RNA in many tissues. LASV infection in the Natal multimammate mice was subclinical, however, clinical chemistry values were transiently altered and immune infiltrates were observed histologically in lungs, spleens and livers, indicating a minor disease with coordinated immune responses are elicited, controlling infection. Intranasal infection resulted in unique virus tissue dissemination dynamics and heightened LASV shedding, compared to subcutaneous inoculation. Our study provides important insights into LASV infection in its natural reservoir using a contemporary infection system, demonstrating that specific inoculation routes result in disparate dissemination outcomes, suggesting intranasal inoculation is important in the maintenance of LASV in the natural reservoir, and emphasizes that selection of the appropriate inoculation route is necessary to examine aspects of viral replication, transmission and responses to zoonotic viruses in their natural reservoirs.

Association between ACTH stimulation test results and clinical signs in dogs with hyperadrenocorticism treated with trilostane

Trilostane is the recommended medical treatment for dogs with hyperadrenocorticicm (HAC). The objective of this study was to investigate the association between ACTH stimulation test (ACTHST) results, and relevant clinical signs, in dogs treated with trilostane. A disease-specific questionnaire was developed, which included the owner's assessment of polydipsia, polyuria, polyphagia, panting, and satisfaction with the treatment, based on a 5-response category rating scale. Forty-nine dogs with HAC were prospectively enrolled. Dogs were grouped according to their recheck appointment (first recheck, 710 days after commencement of treatment or change of trilostane dose; second recheck, 4 weeks after the first recheck; third recheck, performed at 3-6 months intervals once the dog was well controlled). At the recheck appointment, the owner's questionnaire responses were recorded, and an ACTHST was performed, along with urine specific gravity measurement. Linear mixed effects models were used to assess differences among the three recheck time points and to test possible associations between ACTHST results and clinical signs. Significant differences between rechecks were present for stimulated cortisol (first to third recheck, P < 0.001; second to third recheck, P < 0.01), polydipsia (first to second recheck, P = 0.001), polyuria (first to second recheck, P < 0.001; first to third recheck, P = 0.001), and owner satisfaction (first to second recheck, P < 0.001; first to third recheck, P < 0.001). Backward stepwise variable elimination did not identify any significant associations between ACTHST results and clinical signs. Therefore, clinical signs of HAC were not predicted based on the ACTHST results.

Hormonally controlled ILC antigen presentation potential is reduced during pregnancy

Strategically located in mucosal barriers, innate lymphoid cells (ILCs) are relevant in local containment and tolerance of commensal microflora. ILCs have been recently described at the fetomaternal interface, where the development of a semi-allogeneic fetus can only succeed in a well-controlled immune environment. We postulate that ILCs adapt their antigen presentation capacity to protect pregnancy from excessive immune responses. Human ILCs were studied in deciduae of term pregnancies, peripheral blood and in in vitro generated ILCs. Fresh isolated lymphocytes or cells treated with pregnancy-related factors were investigated. The fetal antigen rejection-based CBA/J × DBA/2J mouse model (poor outcome pregnant mice; POPM) was used to characterize ILC antigen presentation potential in normal and immunologically disturbed pregnancies. ILC antigen presentation potential was characterized by flow cytometry and qPCR. We discovered that the distribution of ILC subsets changed during both human and murine pregnancy. Moreover, the pregnancy was accompanied by reduced MHCII expression in splenic ILCs during normal pregnancy (CBA/J × BALB/c; good outcome pregnant mice; GOPM) but increased in splenic and intestinal ILCs of CBA/J × DBA/2J mice. In vitro, splenic ILCs from pregnant mice increased MHCII expression after stimulation with IL-1β and IL-23. In contrast, uterine ILCs displayed lower MHCII expression, which remained unchanged after stimulation. Finally, pregnancy-related factors and hormones present in the uterine environment reduced antigen presentation potential of human ILCs in vitro. Together, these data indicate that, during pregnancy, peripheral and especially uterine ILCs adapt their antigen presenting potential to maintain a level of tolerance and support pregnancy.

The impact of early musical training on striatal functional connectivity

Evidence from language, visual and sensorimotor learning suggests that training early in life is more effective. The present work explores the hypothesis that learning during sensitive periods involves distinct brain networks in addition to those involved when learning later in life. Expert pianists were tested who started their musical training early (<7 years of age; n = 21) or late (n = 15), but were matched for total lifetime practice. Motor timing expertise was assessed using a musical scale playing task. Brain activity at rest was measured using fMRI and compared with a control group of nonmusicians (n = 17). Functional connectivity from seeds in the striatum revealed a striatal-cortical-sensorimotor network that was observed only in the early-onset group. In this network, higher connectivity correlated with greater motor timing expertise, which resulted from early/late group differences in motor timing expertise. By contrast, networks that differentiated musicians and nonmusicians, namely a striatal-occipital-frontal-cerebellar network in which connectivity was higher in musicians, tended to not show differences between early and late musicians and not be correlated with motor timing expertise. These results parcel musical sensorimotor neuroplasticity into a set of musicianship-related networks and a distinct set of predominantly early-onset networks. The findings lend support to the possibility that we can learn skills more easily early in development because during sensitive periods we recruit distinct brain networks that are no longer implicated in learning later in life.

Rezidivraten und Form des Rezidivs nach endoluminaler Ablation der Vena saphena magna – Ein Vergleich von Laserablation (EVLA) 1470 nm, Radiofrequenz (RFITT und ClosureFast) sowie Heißdampf mit einer durchschnittlichen Nachbeobachtungszeit von 3,8 Jahren

Einleitung Erkrankungen des Venensystems, insbesondere auch die Insuffizienz der Vena saphena magna (VSM), gehören zu den häufigsten Krankheitsbildern in unserer Gesellschaft. Zur Behandlung stehen neben Krossektomie und Stripping sowie reiner Sklerosierungstherapie verschiedene endovenöse thermische Verfahren zur Verfügung, die in der vorliegenden Studie untereinander verglichen werden sollten.

Methoden Zwischen 2009 und 2013 wurde bei insgesamt 297 Patienten die insuffiziente VSM mit einer der 4 Methoden EVLA 1470 nm, ClosureFast, RFITT oder Heißdampf abladiert. Als primärer Endpunkt wurde die Rezidiv-Häufigkeit definiert. Die Nachkontrollen mit Duplexsonografie fanden 14 Tage postoperativ, 3 Monate postoperativ, nach 1 Jahr und schließlich jährlich mit einer durchschnittlichen Nachbeobachtungszeit von 3,8 Jahren und einer Follow-up-Rate von 81 % statt.

Ergebnisse Zum Zeitpunkt der letzten Nachkontrolle zeigten sich folgende anatomische Erfolgsraten der behandelten VSM: ClosureFast 95 %, EVLA 97 %, RFITT 79 % und Heißdampf 71 %. Schwerwiegende Komplikationen traten nur beim Heißdampf auf (Nekrosen an der Punktionsstelle), die Schmerzintensität lag bei allen Methoden 14 Tage postoperativ bei einem Median von 1–3 auf einer Skala von 1–10, bei den nachfolgenden Kontrollen lag der Median bei allen Methoden bei 1. Sowohl der Global Index Score (CIVIQ-Score) als auch der Venous Clinical Severity Score (VCSS) ließen sich durch alle endovenösen thermischen Methoden signifikant verbessern. In 5–12 % der Fälle trat ein Reflux der zuvor suffizienten Vena saphena magna accessoria (VSAA) auf.

Diskussion EVLA und ClosureFast sind zur Behandlung von Insuffizienzen der VSM mit hoher Erfolgsrate und vergleichbaren Ergebnissen zu Krossektomie und Stripping geeignet. Die Verfahren RFITT und Heißdampf zeigen im Vergleich signifikant niedrigere Verschlussraten und sind damit besonderen Situationen vorbehalten. Besonderes Augenmerk sollte auf das Vorhandensein einer zunächst nicht refluxiven VSAA gerichtet werden. Da sich hier eine erhöhte Rezidivrate bei dieser Vene zeigte, erscheint es sinnvoll, die VSAA primär mit zu abladieren.

Comparison of four commercially available point-of-care tests to detect antibodies against canine distemper virus in dogs

Pre-vaccination antibody testing to determine dogs' immunity against canine distemper virus (CDV) is increasingly used. Four point-of-care tests (POC A-D) are available in Europe, but their diagnostic accuracy has not been compared. The study evaluated the diagnostic accuracy and usability of these tests. Sera of client-owned dogs (n = 198; healthy n = 22; unhealthy dogs n = 176) and specific pathogen-free (SPF) dogs (n = 40) were included. Virus neutralisation (VN) was performed as the reference standard. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy (OA) were determined. McNemar's test was used to determine significant differences between specificity and sensitivity of the tests and Cohen's kappa was used to assess agreement. The prevalence of anti-CDV antibodies by VN was 80% in client-owned dogs overall, with 100% prevalence in healthy dogs, and 0% in SPF dogs. POC-C and POC-D were considered easiest to perform. Specificity of all tests was high using sera from SPF dogs (88-100%). In healthy dogs, sensitivity was variable (45-98%). Specificity was low in all four POC tests when using sera from acutely ill dogs (6-53%) and clinically healthy dogs with chronic disease (5-77%). In client-owned dogs, including healthy and unhealthy dogs, agreement was poor between tests. All POC tests had a low specificity when investigating sera from ill client-owned dogs and usefullness of these tests especially in dogs that are acutely ill or have chronic disease is not supported by this study.

Changes in renal parameters and their association with subclinical vector-borne infections in Bernese Mountain dogs

Background

An increased risk for glomerulonephritis and a higher prevalence of antibodies to Borrelia (B.) burgdorferi sensu lato have been reported in Bernese mountain dogs (BMDs). The aim of the study was to determine the prevalence of laboratory abnormalities suggestive of kidney disease in clinically healthy BMDs compared to a control population and to investigate if there is a correlation with the occurrence of antibodies to B. burgdorferi sensu lato, Ehrlichia canis, and Anaplasma (A.) spp. and with the occurrence of Dirofilaria (D.) immitis antigen.

A total of 197 BMDs and 57 control dogs were included in the study. Laboratory evidence of kidney disease was defined as renal azotemia and/or proteinuria with a urine protein creatinine ration of more than 0.5 in an inactive urine sediment. A SNAP®4Dx® ELISA (IDEXX, Laboratories, Inc., Westbrook, ME, USA) was used to detect antibodies to B. burgdorferi sensu lato, E. canis and Anaplasma spp. and antigen of D. immitis.

Results

Laboratory evidence of kidney disease was significantly more common in BMDs than in control dogs (17.8% versus 1.8%) (p = 0.005). The proportion of BMDs with anti-B. burgdorferi sensu latu antibodies and anti-A. phagocytophilum antibodies was significantly higher in BMDs (p <  0.001). However, an association between these findings could not be identified.

Conclusion

BMDs are more often affected by kidney disease and have a higher prevalence of antibodies to bacterial pathogens transmitted by Ixodes ticks than control dogs. However, a causal relationship between these two variables could not be established due to a lack of association between these two findings.

AllergoOncology: ultra-low IgE, a potential novel biomarker in cancer-a Position Paper of the European Academy of Allergy and Clinical Immunology (EAACI)

Elevated serum IgE levels are associated with allergic disorders, parasitosis and specific immunologic abnormalities. In addition, epidemiological and mechanistic evidence indicates an association between IgE-mediated immune surveillance and protection from tumour growth. Intriguingly, recent studies reveal a correlation between IgE deficiency and increased malignancy risk. This is the first review discussing IgE levels and links to pathological conditions, with special focus on the potential clinical significance of ultra-low serum IgE levels and risk of malignancy. In this Position Paper we discuss: (a) the utility of measuring total IgE levels in the management of allergies, parasitosis, and immunodeficiencies, (b) factors that may influence serum IgE levels, (c) IgE as a marker of different disorders, and d) the relationship between ultra-low IgE levels and malignancy susceptibility. While elevated serum IgE is generally associated with allergic/atopic conditions, very low or absent IgE may hamper anti-tumour surveillance, indicating the importance of a balanced IgE-mediated immune function. Ultra-low IgE may prove to be an unexpected biomarker for cancer risk. Nevertheless, given the early stage of investigations conducted mostly in patients with diseases that influence IgE levels, in-depth mechanistic studies and stratification of malignancy risk based on associated demographic, immunological and clinical co-factors are warranted.

[COVID-19 in hospitalized children and adolescents]

BACKGROUND

The clinical knowledge about the course, complications and treatment of COVID-19 in children and adolescents is so far limited.

AIM

This systematic review summarizes the current scientific evidence regarding the clinical presentation of COVID-19 in hospitalized children based on available case series from China. In addition, first data from a nationwide pediatric hospital survey conducted by the German Society for Pediatric Infectious Diseases (DGPI) are presented.

METHODS

This study evaluated 12 case series from China with 6-2143 children infected with SARS-CoV‑2, which were identified by a literature search in PubMed up to 31 March 2020. The database of the German nationwide DGPI COVID-19 survey was accessed on 6 April 2020.

RESULTS

The median patient age in the case series was between 2 and 7 years and 18-45% were infants <1 year of age. The duration of hospital stay was 5-20 days. Most commonly reported symptoms were fever and cough; in 40-100% of cases involvement of the lower respiratory tract was reported, usually confirmed by computed tomography (CT). Severe and critical courses of disease were reported in up to 8% of the children including 2 fatalities. So far the German DGPI COVID-19 survey reported 33 hospitalized children up to 6 April 2020, mostly with upper airway infections. Of these children, 45% were infants and 32% had an underlying medical condition. So far 3 children (9%) needed admission to an intensive care unit.

CONCLUSION

COVID-19 in hospitalized children usually presented as an uncomplicated febrile upper airway infection or mild pneumonia. Severe cases or fatalities rarely occurred in children. Information on neonates and children with underlying chronic conditions as well as on therapeutic and preventive measures are urgently needed.

Prevalence of prediabetes and type 2 diabetes in children with obesity and increased transaminases in European German-speaking countries. Analysis of the APV initiative

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), prediabetes and type 2 diabetes mellitus are known to be closely linked with obesity as early as during childhood.

OBJECTIVES

The study aimed to determine the prevalence of prediabetes and T2DM in children with obesity with or without increased transaminases.

METHODS

Data from the observational multicentre (n = 51), cross-sectional Adipositas Patienten Verlaufsbeobachtung registry were analyzed. Mild increase (mild group) was defined by alanine transaminase (ALT) >24 to ≤50 U/L and moderate to severe increase (advanced group) by ALT > 50 U/L. Prediabetes and T2DM were defined according to recent IDF/ISPAD guidelines.

RESULTS

The prevalence of prediabetes and T2DM was 11.9% (95% CI: 11.0-12.8) and 1.4% (95% CI: 1.1-1.7) among all participants (n = 4932; male = 2481; mean age 12.9 ± 2.7 years; BMI-SDS 2.1 ± 0.5; Tanner stage 3.2 ± 1.5). The prevalence of impaired glucose metabolism (prediabetes and T2DM) was 13.8% (95% CI: 12.1-15.4) in the mild, 21.9% (95% CI: 18.8-25.1) in the advanced group, 10.7% (95% CI: 9.4-11.9) in the control group. Mild and advanced groups had greater odds ratios for prediabetes [1.42; 95% CI: 1.17-1.72, 2.26-fold; (1.78-2.86), respectively], the advanced group also for T2DM [2.39 (1.36-4.21)] compared to controls. While an increase in transaminases predominantly affected boys, girls within the advanced group had a higher T2DM prevalence than males (5.4 vs. male 2.1%).

CONCLUSIONS

Children with obesity and increased liver transaminases as surrogates of NAFLD should be screened for T2DM.

Comparative pathogenesis of Ebola virus and Reston virus infection in humanized mice

Filoviruses of the genus Ebolavirus include 6 species with marked differences in their ability to cause disease in humans. From the highly virulent Ebola virus to the seemingly nonpathogenic Reston virus, case fatality rates can range between 0% and 90%. In order to understand the molecular basis of these differences, it is imperative to establish disease models that recapitulate human disease as faithfully as possible. Nonhuman primates (NHPs) are the gold-standard models for filovirus pathogenesis, but comparative studies are skewed by the fact that Reston virus infection can be lethal for NHPs. Here we used HLA-A2-transgenic, NOD-scid-IL-2γ receptor-knockout (NSG-A2) mice reconstituted with human hematopoiesis to compare Ebola virus and Reston virus pathogenesis in a human-like environment. While markedly less pathogenic than Ebola virus, Reston virus killed 20% of infected mice, a finding that was linked to exacerbated inflammation and viral replication in the liver. In addition, the case fatality ratios of different Ebolavirus species in humans were recapitulated in the humanized mice. Our findings point to humanized mice as a putative model to test the pathogenicity of newly discovered filoviruses, and suggest that further investigations on Reston virus pathogenesis in humans are warranted.

Complement 3+-astrocytes are highly abundant in prion diseases, but their abolishment led to an accelerated disease course and early dysregulation of microglia

Astrogliosis and activation of microglia are hallmarks of prion diseases in humans and animals. Both were viewed to be rather independent events in disease pathophysiology, with proinflammatory microglia considered to be the potential neurotoxic species at late disease stages. Recent investigations have provided substantial evidence that a proinflammatory microglial cytokine cocktail containing TNF-α, IL-1α and C1qa reprograms a subset of astrocytes to change their expression profile and phenotype, thus becoming neurotoxic (designated as A1-astrocytes). Knockout or antibody blockage of the three cytokines abolish formation of A1-astrocytes, therefore, this pathway is of high therapeutic interest in neurodegenerative diseases. Since astrocyte polarization profiles have never been investigated in prion diseases, we performed several analyses and could show that C3⁺-PrP^Sc-reactive-astrocytes, which may represent a subtype of A1-astrocytes, are highly abundant in prion disease mouse models and human prion diseases. To investigate their impact on prion disease pathophysiology and to evaluate their potential therapeutic targeting, we infected TNF-α, IL-1α, and C1qa Triple-KO mice (TKO-mice), which do not transit astrocytes into A1, with prions. Although formation of C3⁺-astrocytes was significantly reduced in prion infected Triple-KO-mice, this did not affect the amount of PrP^Sc deposition or titers of infectious prions. Detailed characterization of the astrocyte activation signature in thalamus tissue showed that astrocytes in prion diseases are highly activated, showing a mixed phenotype that is distinct from other neurodegenerative diseases and were therefore termed C3⁺-PrP^Sc-reactive-astrocytes. Unexpectedly, Triple-KO led to a significant acceleration of prion disease course. While pan-astrocyte and -microglia marker upregulation was unchanged compared to WT-brains, microglial homeostatic markers were lost early in disease in TKO-mice, pointing towards important functions of different glia cell types in prion diseases.

Richtigstellung: Saphenofemorale Rezidive nach endovenöser thermischer Therapie und nach chirurgischer Therapie

Die Arbeitsgruppe Mumme, Mühlberger, Sidhwa und Hummel haben mit ihrer Arbeit „Alarmierend hohe Rate saphenofemoraler Rezidive nach endovenöser Lasertherapie“ (Phlebologie 2019;48:18–22) mehrere Behauptungen aufgestellt, die nochmals genauer beleuchtet werden müssen.

Abstract P4-02-12: Comparison of RT-qPCR with consensus immunohistochemistry by three pathologists for ER, PR, HER2 and Ki-67 in Chinese breast cancer patients

Background

During the diagnostic work-up of breast carcinomas, immunohistochemistry (IHC) is the currently used method for assessing the expression of estrogen- (ER) and progesterone-receptors (PR), human epidermal growth factor receptor 2 (HER2) as well as of Ki-67 as a marker of tumor cell proliferation. In this study, we analyzed the concordance of these four breast cancer biomarkers between the RT-qPCR- and IHC-based (evaluated by three independent pathologists) determinations.

Methods

The expression of ER/ESR1, PR/PGR, HER2/ERBB2 and Ki-67/MKI67 was determined in 269 FFPE breast cancer samples with tumor content &gt;20% from Chinese patients. For IHC, the samples were freshly cut, stained and assessed by three independent pathologists using the same scoring methods in a blinded fashion (positivity defined as: ER/PR ≥1%, HER2 &gt;2+ and Ki-67 ≥20%). Measurement of the markers on the mRNA level was done on total RNA extracts prepared from whole tissue sections from the same FFPE blocks using the CE-marked RT-qPCR based IVD MammaTyper® on a Cobas® z480 qPCR cycler. IHC assessments of the three pathologists were compared to each other with regard to concordance of positive/negative results. Subsequently, agreement of RT-qPCR and IHC results for each marker and in samples in which the three pathologists had a consensus positive/negative IHC result was determined. Furthermore, we compared the MammaTyper® assessments from a subset of whole FFPE sections to data obtained from paired samples enriched for invasive carcinoma via macrodissection.

Results

From the 269 samples, 256 were available for final analysis. When excluding cases with discordant IHC callings between the three pathologists (6.0% for ER; 7.4% PR; 4.1% Her2; 17.1% Ki-67)) the concordance to the RT-qPCR determination and consensus IHC-based analysis displayed an excellent agreement for ER (OPA: 95.4%, PPA: 97.5%, NPA: 91.5%, Kappa: 0.897), PR (OPA: 91.1%, PPA: 89.6%, NPA: 93.1%, Kappa: 0.820) and HER2 (OPA: 97.1%, PPA: 91.9%, NPA: 100.0%, Kappa: 0.936). For cancer MKI67 mRNA and Ki-67 protein expression, a lower but still good concordance was found (OPA: 90.1%, PPA: 91.8%, NPA: 83.3%, Kappa: 0.707). In addition, we could demonstrate an excellent agreement of quantitative RT-qPCR measurements between whole surface and paired tumor-enriched samples in 99 Chinese breast cancer patients with R2 of 0.927 for ER, 0.926 for PR, 0.923 for HER2 and 0.908 for KI67. Even under highly standardized IHC scoring conditions, the discordance rates in the RT-qPCR marker callings with 0.0% for ESR1, 5.0% for PGR, 3.0% for ERBB2, 13.1% for MKI67 were lower than disagreements by three pathologists on the identical slide.

Conclusion

Standardized determination of the breast cancer biomarkers ER, PR, HER2 and Ki-67 on the mRNA level shows high concordance to a consensus IHC determined by three experienced pathologists indicating that RT-qPCR may be a valid alternative for determining the four breast cancer biomarkers. In line with previous research we could show on a large set of samples that macrodissection is not required for reliable assessment of the four breast cancer markers in clinical FFPE samples.

Citation Format: Teng X, Li X, Xu S, Zhang J, Hartmann K, Laible M, Hipfel R, Bai Y, Ba X, Wu Z, Wirtz RM, Liu S, Ugur S. Comparison of RT-qPCR with consensus immunohistochemistry by three pathologists for ER, PR, HER2 and Ki-67 in Chinese breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-02-12.

Abstract P2-07-08: Standardized prediction of Oncotype DX® risk classes by local RT-qPCR

Background: Recent results from the prospective validation of the Oncotype DX® recurrence score (RS) have underlined the clinical validity of the assay for the prediction of chemotherapy benefit in ER+/HER2- early stage breast cancer patients. Due to health economic restrictions, some patients have no easy access to the test. A pre-selection of tumor samples may help identify patients with a high likelihood to be spared chemotherapy. Histology and semi-quantitative IHC are hence used to select samples for Oncotype testing, but these suffer from intra- and inter-observer variability, especially for Ki-67 which is a main factor in most RS prediction algorithms. We have established and validated a tool for the prediction of RS risk classes (TAILORx cutoff RS ≤25) based on highly standardized, reproducible and locally performed RT-qPCR measurements of ERBB2, ESR1, PGR and MKI67 mRNA using the CE-marked IVD MammaTyper®.

Methods: Total RNA was extracted from whole surface 10μm sections from FFPE breast cancer samples with a known RS result and a tumor cell content ≥20%. ERBB2, ESR1, PGR and MKI67 mRNA expression was measured by RT-qPCR on a CFX96 qPCR cycler using the MammaTyper® kit. A prediction model for an RS ≤25 result was established using multivariable logistic regression. Based on this model and the training data two cutoffs for confident prediction of low chemotherapy benefit patients in a clinical setting were established at 95% and 97.5% specificity. The model and the cutoffs were then fixed and validated in a second, separate set of breast cancer samples. ROC analysis was used to characterize predictive power of the continuous values resulting from the prediction model. Positive and negative predictive values for detection of an RS ≤25 result were also determined on the validation samples using the two pre-defined cutoffs.

Results: The sample set for training of the prediction model encompassed 202 samples including 29 samples (14.4%) with an RS &gt;25. In an initial multivariable model with all four markers, PGR and MKI67 were the strongest predictors while the influence of ESR in the model was lower, but still significant. ERBB2 was no significant predictor in this set of ERBB2 negative samples and was therefore excluded from the final model which was based on three markers only. This three marker model achieved an AUC of 0.920 (95% CI: 0.871-0.968) in the training samples. When applying the fixed model from the training dataset to a second separately collected set of 104 samples containing 20 samples (19.2%) with an RS &gt;25, an AUC of 0.883 (95% CI: 0.810-0.955) was documented. When further applying the two predefined cutoffs established in the training set, 45 and 36 of the 104 validation samples (43.3% and 34.6%) had a predicted low chemotherapy benefit result (RS ≤25). Even with the less stringent cutoff, not a single one of the RS &gt;25 cases from the validation cohort was falsely predicted as RS ≤25 sample.

Conclusion: We have established a highly reliable method for prediction of Oncotype DX® low chemotherapy benefit results based on local and cost effective mRNA measurements. This method enables local pathologies to pre-assess routine samples using a highly precise molecular tool and thereby reserve the Oncotype DX® test for cases with ambiguous cancer biology.

Citation Format: Lehr H-A, Aulmann S, Etzrodt A, Laible M, Hartmann K, Gürtler C, Wirtz RM, Sahin U, Varga Z. Standardized prediction of Oncotype DX® risk classes by local RT-qPCR [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-07-08.

Eine jugendpsychiafrische Befundkarfe für erziehungsschwierige Minderjährige

Es wird über eine jugendpsychiatrische Befundkaxte für verwahrlosungsgefährdete bzw. verwahrloste Minderjährige berichtet. Die Befundkarte ist auf männliche Minderjährige spezifiziert, aber mit sinngemäßen Abänderungen und Ergänzungen auch für weibliche Minderjährige zu verwenden. Sie soll sowohl der gutachtlichen Beurteilung des einzelnen Verwahrlosten als auch der statistischen Analyse größerer Verwahrlostenkollektive dienen.

Für die gutachterliche Beurteilung des einzelnen Verwahrlosten enthält die Befundkarte einen Katalog von Verwahrlosungsmerkmalen, auf welchem der Untersucher die jeweils erhobenen Befunde registrieren und ihre Anzahl und Valenz ablesen kann.

Für die statistische Analyse größerer Verwahrlostenkollektive ist die Befundkarte mit einer Lochkarte kombiniert, auf welcher alle ermittelten Befunde abgelocht und für statistische Berechnungen ausgezählt werden können.

Das methodische Prinzip der Befundkarte wird auch für die gutachtliche Beurteilung und statistische Analyse anderer psychopathologischer Syndrome empfohlen.

Abstract P1-06-11: Prediction of oncotype DX® results based on local gene expression measurements by MammaTyper®

Background: Oncotype DX® recurrence score (RS) has emerged as a recommended risk classifier for patients with ER+/HER2- early-stage breast cancer. While RS is one of the most rigorously studied risk scores, it is also one of the most expensive tests, thus remaining beyond reach for a many patients.

The necessity for an affordable method for estimating risk of recurrence has motivated investigations on the correlation between RS and traditional parameters such as IHC for ER, PR and Ki67. However, semi-quantitative IHC lacks standardization across different laboratories especially for Ki67.

In this study we therefore investigated whether the standardized assessment of HER2, ER, PR, and Ki67 on mRNA level could better serve for prediction of low risk RS cases.

Methods: ERBB2, ESR1, PGR and MKI67 mRNA expression was measured by RT-qPCR in extracts from FFPE breast cancer samples using the MammaTyper® test. Complete data for RS, IHC, grading and mRNA measurement was available for 198 samples. Tumor subtypes according to St Gallen surrogate definition from 2013 were assigned based on binary mRNA marker classification (pos/neg) according to pre-defined cut-offs. Subtype results were compared to RS risk classes based on commercial and TAILORx-trial cut-offs. RS low risk classification (RS ≤25) based on four IHC markers and grading was estimated using the online tool breastrecurrenceestimator.onc.jhmi.edu and compared to observed RS classes.

Finally, the prediction of continuous RS values by mRNA or semi-quantitative IHC measurement was compared by linear regression and subsequent ROC analysis of prediction models.

Results: The distribution of RS risk classes in the set of samples with full data was 21% RS 0-10, 39% RS 11-17, 27% RS 18-25, 7% RS 26-30 and 7% RS &gt;30. MammaTyper® called 38% (76) of the samples as Luminal A-like. From these samples 70% and 99% had RS values below 18 and 25 respectively. Only 1 MammaTyper® Luminal A-like sample had an RS &gt;30.

Estimation of RS according to the online tool resulted in classification of 61% (121) of the samples as low risk (RS ≤25). Of these 74% and 98% of samples had observed RS values below 18 and between 18 and 25 respectively. 2 and 1 samples called as low risk by the online tool had an RS of 26-30 and &gt;30 and, respectively.

In linear regression analysis of IHC against RS only PR and Ki67 were significant predictors (p-values &lt;0.0001 and 0.0128) while when using mRNA values ESR1, PGR and MKI67 were found as predictors of RS in the multivariate model (all p-values &lt;0.0001). On a training set (67% of samples) the IHC based prediction model was correlated to the observed RS with an R2 of 0.305 whereas the mRNA based model achieved an R2 of 0.489. When the models were applied to training and validation dataset (33% of samples) for prediction of an RS &gt;25 result, the IHC based model had AUCs of 0.887 and 0.836, respectively, while the mRNA based model achieved AUCs of 0.909 and 0.899, respectively.

Conclusion: mRNA based prediction of RS was considerably better than prediction based on IHC. As Ki67 IHC standardization is reaching its limits, local gene expression measurements with their high degree of standardization could serve as a safer way for prediction of Oncotype low risk results.

Citation Format: Lehr H-A, Aulmann S, Laible M, Etzrodt A, Hartmann K, Gürtler C, Sahin U, Varga Z. Prediction of oncotype DX® results based on local gene expression measurements by MammaTyper® [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-06-11.

Abstract P3-08-14: Prediction of distant recurrence in low risk early breast cancer by RT-qPCR based subtyping using MammaTyper®

Background:

Estrogen receptor (ER/ESR1), progesterone receptor (PR/PGR) and epidermal growth factor receptor 2 (HER2/ERBB2) are routinely assessed by immunohistochemistry (IHC) during workup of breast cancer samples. The routine use of Ki67 (MKI67) IHC assessment in the context of breast cancer subtyping, however, remains controversial, due to poor reproducibility and lack of standardization.

The MammaTyper® test is an in-vitro diagnostic (IVD) test which measures the expression status of the four breast cancer biomarkers ERBB2, ESR1, PGR and MKI67 on the mRNA level via reverse transcription-quantitative PCR (RT-qPCR) and has demonstrated a high degree of reproducibility in the assessment of the four markers.

In this retrospective analysis we assessed the prognostic power of molecular subtyping by MammaTyper® in archived samples from low risk early breast cancers treated with adjuvant endocrine therapy only.

Methods:

ER+/HER2- (according to initial diagnosis) FFPE breast cancer samples from patients treated with adjuvant endocrine therapy only were obtained from 6 different centers. Tumor cellularity was assessed by H&E staining and RNA was extracted from samples with a tumor cell content of ≥20% using a bead-based RNA purification kit (RNXtract®). Total RNA was then used as input for MammaTyper® RT-qPCR. Expression values were classified as positive or negative for each marker based on predefined cutoff values. Tumor subtypes were assigned to each sample based on the combination of binary (pos/neg) single marker expression status according the St Gallen surrogate subtype definition. Distant disease free survival of Luminal A-like samples vs. samples with other subtypes was assessed by Kaplan Meier analysis and Cox regression using SAS version 9.4.

Results:

The final analysis included 319 samples with sufficient tumor cellularity and RNA content for reliable analysis. The rate of distant recurrence in the analyzed set was 8.5%. Median follow up was 7.8 years. The MammaTyper® test called 60% (192) of samples as Luminal-A-like (4.7% (9) distant events), 37% (119) as Luminal B-like (HER2 negative) (13.4% (16) distant events), 1.3% (4) as Triple negative (ductal) (25% (1) distant events), 0.6% (2) as “not defined according to St Gallen” (ESR1-/PGR+) (50% (1) distant events) and 0.6% (2) as Luminal B-like (HER2 positive) (no distant events).

When comparing Luminal A-like samples with the samples of the other subtypes in survival analysis, Luminal A-like samples had a significantly better distant disease free survival when assessing samples from patients with pN0 status (278) (p=0.0177, HR=0.344 (95% CI 0.137-0.866), pN1 status (0-3 affected nodes) (314) (p=0.0153, HR=0.374 (95% CI 0.163-0.855) as well as for all samples (p=0.0032, HR=0.319 (95% CI 0.143-0.711).

Conclusion:

Determination of HER2, ER, PR and Ki67 mRNA levels allows molecular subtyping according to the St Gallen surrogate subtype definition. Low risk of distant recurrence could be confirmed for the MammaTyper® Luminal A-like samples suggesting that for this patient group endocrine treatment alone may be sufficient. The high degree of standardization of mRNA measurement may drive the use of the Ki67/MKI67 biomarker in routine breast cancer pathology.

Citation Format: Laible M, Hartmann K, Gürtler C, Anzeneder T, Weber S, Keller T, Sahin U. Prediction of distant recurrence in low risk early breast cancer by RT-qPCR based subtyping using MammaTyper® [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-08-14.

Akuter blutiger Durchfall als Vorstellungsgrund bei einem Hund mit primärem Hypoadrenokortizismus

Ein 7 Jahre alter, männlich-kastrierter Schäferhundmischling wurde wegen akuten blutigen Erbrechens und wässrig-blutigen Durchfalls vorgestellt. Aufgrund klinischer Präsentation, unspezifischer Laborwertveränderungen, unauffälliger Elektrolytwerte und schneller klinischer Besserung auf Infusionstherapie wurde die Diagnose “hämorrhagische Gastroenteritis” (HGE) gestellt. Bei erneuter Vorstellung des Hundes wegen Leistungsschwäche einen Monat später bestanden Elektrolytverschiebungen (Hyperkaliämie und Hyponatriämie), die charakteristisch für einen typischen Hypoadrenokortizismus sind. Mittels ACTH-Stimulationstest wurde eine Unterfunktion der Nebennierenrinde bestätigt. Dieser Fallbericht zeigt, dass sich Patienten in einer Addison-Krise mit akutem hämorrhagischem Durchfall präsentieren können. Durch Erbrechen und Durchfall kann es zu einem Kaliumverlust über den Gastrointestinaltrakt kommen, wodurch typische Elektrolytverschiebungen für einen Morbus Addison verschleiert werden. Im Zweifelsfall sollte bei jedem Patienten mit blutigem Durchfall zum Ausschluss eines Hypoadrenokortizismus eine Bestimmung der basalen Kortisolkonzentration erfolgen.

Feline lower urinary tract disease in a German cat population

Objective: To investigate epidemiologic data, clinical signs, results of urinalysis and causes of lower urinary tract disease in a German veterinary hospital population of cats and to determine if the demographic data, history, clinical signs and urinalysis results correlate with a particular etiology. Materials and methods: Cats presented with signs of feline lower urinary tract disease (FLUTD) with a documented history and physical examination, a complete urinalysis (urine specific gravity, urine dipstick and sediment, urine culture) of urine obtained by cystocentesis or catheterization, and diagnostic imaging of the urinary tract were included into the study. Cats that had received a previous treatment during the same episode of FLUTD were excluded. Results: A total of 302 cats were included into the study. Cats with FLUTD presented throughout the seasons with similar frequency. The most common diagnosis was feline idiopathic cystitis (FIC) (55.0%), followed by bacterial urinary tract infection (UTI) (18.9%), urethral plug (10.3%) and urolithiasis (7.0%). Urethral obstruction was significantly more frequent in cats with FIC than in cats with UTI. Cats with FIC and urethral plugs were significantly younger and had significantly higher body weights than cats with UTI and neoplasia. FIC and urethral plugs were significantly more common causes of FLUTD in cats younger than 10 years compared to cats that were 10 years or older (65.2% versus [vs.] 35.8% and 13.3% vs. 3.0%), while the incidences of UTI and neoplasia increased with age (12.9% vs. 41.8% and 1.0% vs. 13.4%). Conclusion and clinical relevance: FIC and UTI are the most common diagnoses in cats with FLUTD, with a significant age-related difference in incidence.

The Rivalta’s test as a diagnostic variable in feline effusions – evaluation of optimum reaction and storage conditions

Objective: The Rivalta’s test is used to diagnose feline infectious peritonitis (FIP) in cats with effusion. Only little information on the influence of sample storage and reaction conditions on test results is available, and diagnostic sensitivity and specificity to diagnose FIP vary considerably between few available studies. This study determined the influence of storage of effusion, modifications on reaction conditions, and inter-observer variation. Material and methods: The Rivalta’s test was repeated up to 21 days after storage at room temperature, in the refrigerator, or freezer. The test was performed by two independent, blinded investigators. It was also performed using different volumes of acetic acid, different acids, and different kinds of water. Results: Even after storage for 21 days, test results were comparable. While inter-observer variation revealed substantial disagreement, different modifications in performance showed no major influence on test outcome. Conclusion: The Rivalta’s test seems to be a very robust test concerning storage conditions. Modifications in reaction condition also do not substantially influence outcome. However, the test is subjective and depends on the evaluating person.

Comparison of auricular and rectal temperature measurement in normothermic, hypothermic, and hyperthermic dogs

Objective: Measurement of rectal temperature is the most common method and considered gold standard for obtaining body temperature in dogs. So far, no study has been performed comparing agreement between rectal and auricular measurements in a large case series. The purpose of the study was to assess agreement between rectal and auricular temperature measurement in normothermic, hypothermic, and hyperthermic dogs with consideration of different environmental conditions and ear conformations. Materials and methods: Reference values for both methods were established using 62 healthy dogs. Three hundred dogs with various diseases (220 normothermic, 32 hypothermic, 48 hyperthermic) were enrolled in this prospective study. Rectal temperature was compared to auricular temperature and differences in agreement with regard to environmental temperature, relative humidity, and different ear conformations (pendulous versus prick ears) were evaluated using Pearson’s correlation coefficient and Bland-Altman analysis. Results: Correlation between rectal and auricular temperature was significant (r: 0.892; p < 0.01). However, Bland-Altman plots showed an inacceptable variation of values (bias: 0.300 °C; limits of agreement: –0.606 to 1.206 °C). This variation was above a maximal clinical tolerance of 0.3 °C, which was established by experts’ opinion (n = 16). Relative humidity had a significant influence (p = 0.001), whereas environmental temperature did not. Conclusion: Variation between the two methods of measuring body temperature was clinically unacceptable. Clinical relevance: Although measurement of auricular temperature is fast, simple, and well tolerated, this method provides a clinically unacceptable difference to the rectal measurement.

Immune mediated destruction of platelets in dogs with heat stroke: A prospective study

Objective: Severe thrombocytopenia is a common sequelae to heat stroke in dogs. So far it has been hypothezised that it is due to disseminated intravascular coagulation. We hypothezised that it is due to immune mediated destruction via antiplatelet antibodies. Material and methods: Prospective evaluation of dogs with heat stroke from May 2005 to August 2008. Dogs that developed severe thrombocytopenia within 5 days of admission were included in the study. All dogs were treated with a standardized treatment protocol. In addition, they received either immunoglobulins or prednisolone. Results: Six dogs were presented with heat stroke during that time period. Four developed a severe thrombocytopenia. All four dogs tested positive for antiplatelet antibodies and did not have elevated D-Dimers at that time. Platelet count in three dogs recovered fully, one dog was euthanized due to liver and renal failure. Conclusion: In those cases thrombocytopenia was due to immune mediated destruction not due to DIC. Clinical rele-vance: Due to the severity of the thrombocytopenia and the high risk for bleeding in those patients, immunosuppressive therapy in addition to DIC prophylaxis should be discussed.

Fallbericht und Literaturübersicht kutaner Dirofilariose

Gegenstand und Ziel: Der Fallbericht erörtert das diagnostische Vorgehen und differenzialdiagnostische Überlegungen bei Patienten mit Mikrofilarämie und negativem Dirofilaria-immitis-Antigentest und diskutiert die Infektion mit Dirofilaria repens und deren Therapie. Material und Methode: Bei einem Hund aus Ungarn wurden im Blutausstrich Mikrofilarien gefunden. Die weitere Diagnostik zur Differenzierung der Mikrofilarien umfasste einen Dirofilaria-immitis-Antigentest, eine Polymerasekettenreaktion zum Nachweis von Dirofilaria immitis und Dipetalonema reconditum sowie eine Saure-Phosphatase-Reaktion zur Diagnose einer Infektion mit Dirofilaria repens. Ergebnisse: Mittels der Saure-Phosphatase-Reaktion konnte eine Infektion mit Dirofilaria repens diagnostiziert werden. Die Therapie gegen die Mikrofilarien erfolgte mit Selamectin. Schlussfolgerung und klinische Relevanz: Bei mikrofilarämischen Patienten muss differenzialdiagnostisch neben einer Infektion mit Dirofilaria immitis eine Infektion mit anderen, weniger pathogenen Parasiten in Betracht gezogen werden, da sich die Notwendigkeit einer Therapie und das Therapieregime je nach Infektion deutlich unterscheiden.

Messung der myokardialen Geschwindigkeit mittels Gewebe-Doppler beim gesunden Hund

Ziele der Studie waren die Evaluierung der myokardialen Gewebegeschwindigkeit mittels Gewebe-Doppler (Tissue Velocity Imaging, TVI) hinsichtlich der Reproduzierbarkeit sowie die Erstellung von Referenzwerten für die systolische und diastolische longitudinale Myokardbewegung. Weiterhin wurde der Einfluss von Geschlecht, Herzfrequenz, Alter, Gewicht und Rasse untersucht. Material und Methoden: Das Probandenkollektiv umfasste 199 gesunde Hunde. Systolische und diastolische longitudinale TVI wurden mittels Farb-Gewebe-Doppler im linksapikalen Vierkammerblick für rechte freie Wand, Septum und linke freie Wand einzeln aufgezeichnet und ausgewertet. Ergebnisse: Die Variationskoeffizienten für die Intrareader-Variabilität lagen alle unter 10%. Die Variationskoeffizienten für die Interreader-Variabilität unterschritten 12,4%. Das TVI wies eine heterogene Verteilung im Myokard mit einem apikobasalen Geschwindigkeitsgradienten für systolische und diastolische Parameter auf. Es zeigte keine Abhängigkeit vom Geschlecht. Dagegen beeinflussten Herzfrequenz, Alter, Gewicht und Rasse das TVI signifikant. Schlussfolgerung und klinische Relevanz: Das TVI stellt eine Technik mit guter Reproduzierbarkeit dar. Nachteil des Verfahrens ist die Abhängigkeit von Herzfrequenz, Alter, Gewicht und Rasse der Hunde. Die Studie belegt, dass das TVI beim Hund als neue Methode in der Echokardiographie eingesetzt werden kann. Diese Arbeit stellt eine Grundlage für weitere Studien auf dem Gebiet der Gewebe-Dopplertechnik dar und liefert für den klinischen Einsatz Referenzwerte für Hunde verschiedener Gewichtsgruppen.

A transatlantic perspective on the integration of immuno-oncology prognostic and predictive biomarkers in innovative clinical trial design

Immuno-therapeutics aim to activate the body's own immune system against cancer and are one of the most promising cancer treatment strategies, but currently limited by a variable response rate. Biomarkers may help to distinguish those patients most likely to respond to therapy; they may also help guide clinical decision making for combination therapies, dosing schedules, and determining progression versus relapse. However, there is a need to confirm such biomarkers in preferably prospective clinical trials before they can be used in practice. Accordingly, it is essential that clinical trials for immuno-therapeutics incorporate biomarkers. Here, focusing on the specific setting of immune therapies, we discuss both the scientific and logistical hurdles to identifying potential biomarkers and testing them in clinical trials.

Cutaneous ulcers following hydroxyurea therapy

Hydroxyurea (HU) is usually a well tolerated antineoplastic agent and is commonly used in the treatment of chronic myeloproliferative diseases. Dermatological side effects are frequently seen in patients receiving longterm HU therapy. Cutaneous ulcers have been reported occasionally.

We report on four patients with cutaneous ulcers whilst on long-term hydroxyurea therapy for myeloproliferative diseases. In all patients we were able to reduce the dose, or stop HU altogether and their ulcers markedly improved. Our observations suggest that cutaneous ulcers should be considered as possible side effect of long-term HU therapy and healing of the ulcers can be achieved not only by cessation of the HU treatment, but also by reducing the dose of hydroxyurea for a limited time.

Die Sklerotherapie mit Luft- oder CO2-O2-Schaum

Ziel und Durchführung: Die Wirksamkeit und Nebenwirkungen der ultraschallgeführten Polidocanol-Schaumsklerosierung (FS) wurde in dieser Anwendungsbeobachtung (AWB) für Luft-FS und CO2-O2-FS über ein internetbasiertes Protokoll dokumentiert.

Material und Methoden: An der AWB nahmen 11 Zentren teil, neun Zentren arbeiteten mit Luft-FS, zwei Zentren mit CO2-O2-FS. Verwendet wurden zugelassene Medikamente. In 553 Behandlungen wurde bei 376 Patienten für die Luft-FS Polidocanol (Aethoxysklerol®, Kreussler) mit 0,25 % bis 4 % verwendet. In 152 Behandlungen erfolgte bei 125 Patienten die CO2-O2-FS mit Polidocanol 1–3 %, mit CO2(Laparox®, Linde) und mit O2 (Conoxia®, Linde) im Verhältnis 70:30. Die Abfüllung bei der CO2-O2-FS erfolgte steril mittels der Massendurchfluss-Messtechnik. Eine klinische Ab-schlussuntersuchung und Ultraschallkontrolle erfolgte zirka 4–6 Wochen nach der letzten Therapie.

Ergebnisse: Krampfadern größer als 3 mm wurden bei Luft-FS im Durchschnitt mit 5,3 ml, bei der CO2-O2–FS mit 8,2 ml behandelt; der Unterschied war signifikant. Nebenwirkungen: Hyperpigmentierungen: Luft 23,3 %, CO2-O2 13,6 %; Hämatom: Luft 14,4 %, CO2-O2 2,5 %; Migräne: Luft 0,1 %, CO2-O2 keine; Matting: Luft 1,4 %, CO2-O2 kein; Brennen: Luft 11,7 %, CO2-O25,5 %; Thrombo-sen: Luft 1,1 %, CO2-O2 1,6 %; Sehstörungen: Luft 0,2 %, CO2-O2 2 %.

In beiden Gruppen ergab sich kein Unterschied in der Sicherheit bei durchschnittlich 5,3 ml Schaum in der Luft-FS und 8,2 ml Schaum in der CO2-O2-FS. Lokale Nebenwirkungen waren in der CO2-O2-Gruppe geringer; in dieser Gruppe war die Behandlung effektiver, da größere Vo-lumen sicher angewandt werden konnten. In beiden Gruppen traten keine zentralneurologischen Nebenwirkungen auf, alle Sehstörungen waren innerhalb von 20 Minuten ohne zusätzliche Therapie spontan reversibel.

Conclusio: Die hier publizierten Ergebnisse stimmen mit über 1 000 Behandlungen für CO2-O2-FS aus der Literatur überein. Unter CO2-O2-FS trat in diesen Arbeiten keine TIA oder Apoplexe auf. Die CO2-O2-FS erscheint ins-gesamt für größere Krampfadern wirksamer als die Luft-FS. Die Verwendung der physiologischen Gase CO2-O2 in der FS ist möglicherweise sicherer als die Luft-FS. Klare Beweise stehen hier noch aus und die mögliche Komplikation der iatrogenen Gasembolie muss immer be-rücksichtigt werden.

Sensitivity and specificity of an in-clinic point-of-care PCR test for the diagnosis of canine leishmaniasis

Canine leishmaniasis is an important infectious disease worldwide. Although commonly used, antibody tests are often falsely negative, and in such cases direct detection of the pathogen, such as PCR, is necessary. However, PCR is only performed in specialized laboratories and not available in all localities. The aim of this study was to compare the sensitivity and specificity of an in-clinic point-of-care (ICPOC) PCR for the diagnosis of canine Leishmania spp. infection to those of a well characterized reference real-time PCR. In this study, 515 samples from 251 dogs (201 EDTA blood samples, 244 conjunctival swabs, 19 lymph node aspirates, and 51 bone marrow aspirates) were collected prospectively and analysed for the presence of Leishmania DNA using an ICPOC test. The results were compared to those of a reference real-time PCR for identification of Leishmania kinetoplast minicircle DNA. Sensitivity and specificity with 95% confidence interval (CI 95%) were determined. Specificity was 100% for all samples examined. Sensitivity was 57.1% (CI 95%, 34.0-78.2) in bone marrow aspirates, 58.8% (CI 95%, 32.9-81.6) in lymph node aspirates, 46.9% (CI 95%, 32.5-61.7) in conjunctival swabs, and 10.0% (CI 95%, 3.3-21.8) in blood. The ICPOC PCR was easy to perform and was reliable in the case of positive test results. A negative result, however, did not exclude infection and therefore requires further diagnostics.

Midostaurin: a magic bullet that blocks mast cell expansion and activation

Clinically relevant features in patients with systemic mastocytosis (SM) include the cosmetic burden of lesional skin, mediator-related symptoms, and organ damage resulting from mast cell (MC) infiltration in advanced forms of SM. Regardless of the SM variant, expansion of neoplastic MC in the skin and other organs is triggered by mutant forms of KIT, the most prevalent being D816V. Activation of MC with subsequent release of chemical mediators is often caused by IgE-dependent mechanisms in these patients. Midostaurin, also known as PKC412, blocks the kinase activity of wild-type KIT and KIT D816V, counteracts KIT-dependent growth of neoplastic MC, and inhibits IgE-dependent mediator secretion. Based on this activity-profile, the drug has been used for treatment of patients with advanced SM. Indeed, encouraging results have been obtained with the drug in a recent multi-center phase II trial in patients with advanced SM, with an overall response rate of 60% and a substantial decrease in the burden of neoplastic MC in various organs. Moreover, midostaurin improved the overall survival and relapse-free survival in patients with advanced SM compared with historical controls. In addition, midostaurin was found to improve mediator-related symptoms and quality of life, suggesting that the drug may also be useful in patients with indolent SM suffering from mediator-related symptoms resistant to conventional therapies or those with MC activation syndromes. Ongoing and future studies will determine the actual value of midostaurin-induced MC depletion and MC deactivation in these additional indications.