PCYT2 deficiency in Saarlooswolfdogs with progressive retinal, central, and peripheral neurodegeneration

We investigated a syndromic disease comprising blindness and neurodegeneration in 11 Saarlooswolfdogs. Clinical signs involved early adult onset retinal degeneration and adult-onset neurological deficits including gait abnormalities, hind limb weakness, tremors, ataxia, cognitive decline and behavioral changes such as aggression towards the owner. Histopathology in one affected dog demonstrated cataract, retinal degeneration, central and peripheral axonal degeneration, and severe astroglial hypertrophy and hyperplasia in the central nervous system. Pedigrees indicated autosomal recessive inheritance. We mapped the suspected genetic defect to a 15 Mb critical interval by combined linkage and autozygosity analysis. Whole genome sequencing revealed a private homozygous missense variant, PCYT2:c.4A>G, predicted to change the second amino acid of the encoded ethanolamine-phosphate cytidylyltransferase 2, XP_038402224.1:(p.Ile2Val). Genotyping of additional Saarlooswolfdogs confirmed the homozygous genotype in all eleven affected dogs and demonstrated an allele frequency of 9.9% in the population. This experiment also identified three additional homozygous mutant young dogs without overt clinical signs. Subsequent examination of one of these dogs revealed early-stage progressive retinal atrophy (PRA) and expansion of subarachnoid CSF spaces in MRI. Dogs homozygous for the pathogenic variant showed ether lipid accumulation, confirming a functional PCYT2 deficiency. The clinical and metabolic phenotype in affected dogs shows some parallels with human patients, in whom PCYT2 variants lead to a rare form of spastic paraplegia or axonal motor and sensory polyneuropathy. Our results demonstrate that PCYT2:c.4A>G in dogs cause PCYT2 deficiency. This canine model with histopathologically documented retinal, central, and peripheral neurodegeneration further deepens the knowledge of PCYT2 deficiency.

Associated Anomalies and Outcome in Patients with Prenatal Diagnosis of Aortic Arch Anomalies as Aberrant Right Subclavian Artery, Right Aortic Arch and Double Aortic Arch

We aimed to evaluate retrospectively associated anomalies and outcome in prenatal aortic arch anomalies (AAAs). We included ninety patients with aberrant right subclavian artery (ARSA), right aortic arch (RAA) with mirror image branching (RAA-mirror) or aberrant left subclavian artery (RAA-ALSA) and double aortic arch (DAA) between 2011 and 2020. In total, 19/90 (21.1%) had chromosomal anomalies, the highest rate being within the ARSA subgroup (17/46, 37%). All (13/13) of the RAA-mirror subgroup, 10/27 (37.0%) of RAA-ALSA, 13/46 (28.3%) of ARSA and 0/4 within the DAA subgroup had additional intracardiac anomaly. The rate of extracardiac anomalies was 30.7% in RAA-mirror, 28.3% in ARSA, 25.0% in DAA and 22.2% in the RAA-ALSA subgroup. A total of 42/90 (46.7%) had isolated AAAs: three (7.1%) with chromosomal anomalies, all trisomy 21 (3/26, 11.5%) within the ARSA subgroup. Out of 90, 19 (21.1%) were lost to follow-up (FU). Two (2.2%) intrauterine deaths occurred, and six (6.7%) with chromosomal anomalies terminated their pregnancy. In total, 63 (70.0%) were liveborn, 3/63 (4.8%) with severe comorbidity had compassionate care and 3/60 (5.0%) were lost to FU. The survival rate in the intention-to-treat cohort was 53/57 (93%). Forty-one (77.4%) presented with vascular ring/sling, two (4.9%) with RAA-ALSA developed symptoms and one (2.4%) needed an operation. We conclude that intervention due to vascular ring is rarely necessary. NIPT could be useful in isolated ARSA cases without higher a priori risk for trisomy 21 and after exclusion of other anomalies.

Relationship between magnetic resonance imaging findings and histological grade in spinal peripheral nerve sheath tumors in dogs

BACKGROUND

Peripheral nerve sheath tumors (PNSTs) are a group of neoplasms originating from Schwann cells or pluripotent cell of the neural crest. Therapeutic options and prognosis are influenced by their degree of malignancy and location.

HYPOTHESIS/OBJECTIVES

Identify magnetic resonance imaging (MRI) features predictive of PNST histologic grade.

ANIMALS

Forty-four dogs with histopathological diagnosis of spinal PNSTs and previous MRI investigation.

METHODS

A multicenter retrospective study including cases with (a) histopathologic diagnosis of PNST and (b) MRI studies available for review. Histologic slides were reviewed and graded by a board-certified pathologist according to a modified French system (FNCLCC) for grading soft tissue sarcomas. The MRI studies were reviewed by 2 board-certified radiologists blinded to the grade of the tumor and the final decision on the imaging characteristics was reached by consensus. Relationships between tumor grade and histological and MRI findings were assessed using statistical analysis.

RESULTS

Forty-four cases met inclusion criteria; 16 patients were PNSTs Grade 1 (low-grade), 19 were PNSTs Grade 2 (medium-grade), and 9 were PNSTs Grade 3 (high-grade). Large volume (P = .03) and severe peripheral contrast enhancement (P = .04) were significantly associated with high tumor grade. Degree of muscle atrophy, heterogeneous signal and tumor growth into the vertebral canal were not associated with grade.

CONCLUSIONS AND CLINICAL IMPORTANCE

Grade of malignancy was difficult to identify based on diagnostic imaging alone. However, some MRI features were predictive of high-grade PNSTs including tumor size and peripheral contrast enhancement.

Genetic Screening Reveals Heterogeneous Clinical Phenotypes in Patients with Dilated Cardiomyopathy and Troponin T2 Variants

Background: Cardiomyopathies (CMs) are a heterogeneous and severe group of diseases that shows a highly variable cardiac phenotype and an incidence of app. 1/100.000. Genetic screening of family members is not yet performed routinely. Patients and methods: Three families with dilated cardiomyopathy (DCM) and pathogenic variants in the troponin T2, Cardiac Type (TNNT2) gene were included. Pedigrees and clinical data of the patients were collected. The reported variants in the TNNT2 gene showed a high penetrance and a poor outcome, with 8 of 16 patients dying or receiving heart transplantation. The age of onset varied from the neonatal period to the age of 52. Acute heart failure and severe decompensation developed within a short period in some patients. Conclusion: Family screening of patients with DCM improves risk assessment, especially for individuals who are currently asymptomatic. Screening contributes to improved treatment by enabling practitioners to set appropriate control intervals and quickly begin interventional measures, such as heart failure medication or, in selected cases, pulmonary artery banding.

Cardiomyocyte hyperplasia and immaturity but not hypertrophy are characteristic features of patients with RASopathies

AIMS

RASopathies are caused by mutations in genes that alter the MAP kinase pathway and are marked by several malformations with cardiovascular disorders as the predominant cause of mortality. Mechanistic insights in the underlying pathogenesis in affected cardiac tissue are rare. The aim of the study was to assess the impact of RASopathy causing mutations on the human heart.

METHODS AND RESULTS

Using single cell approaches and histopathology we analyzed cardiac tissue from children with different RASopathy-associated mutations compared to age-matched dilated cardiomyopathy (DCM) and control hearts. The volume of cardiomyocytes was reduced in RASopathy conditions compared to controls and DCM patients, and the estimated number of cardiomyocytes per heart was ~4-10 times higher. Single nuclei RNA sequencing of a 13-year-old RASopathy patient (carrying a PTPN11 c.1528C > G mutation) revealed that myocardial cell composition and transcriptional patterns were similar to <1 year old DCM hearts. Additionally, immaturity of cardiomyocytes is shown by an increased MYH6/MYH7 expression ratio and reduced expression of genes associated with fatty acid metabolism. In the patient with the PTPN11 mutation activation of the MAP kinase pathway was not evident in cardiomyocytes, whereas increased phosphorylation of PDK1 and its downstream kinase Akt was detected.

CONCLUSION

In conclusion, an immature cardiomyocyte differentiation status appears to be preserved in juvenile RASopathy patients. The increased mass of the heart in such patients is due to an increase in cardiomyocyte number (hyperplasia) but not an enlargement of individual cardiomyocytes (hypertrophy).

Serum anti-GM2 and anti-GalNAc-GD1a ganglioside IgG antibodies are biomarkers for immune-mediated polyneuropathies in cats

Recent work identified anti-GM2 and anti-GalNAc-GD1a IgG ganglioside antibodies as biomarkers in dogs clinically diagnosed with acute canine polyradiculoneuritis, in turn considered a canine equivalent of Guillain-Barré syndrome. This study aims to investigate the serum prevalence of similar antibodies in cats clinically diagnosed with immune-mediated polyneuropathies. The sera from 41 cats clinically diagnosed with immune-mediated polyneuropathies (IPN), 9 cats with other neurological or neuromuscular disorders (ONM) and 46 neurologically normal cats (CTRL) were examined for the presence of IgG antibodies against glycolipids GM1, GM2, GD1a, GD1b, GalNAc-GD1a, GA1, SGPG, LM1, galactocerebroside and sulphatide. A total of 29/41 IPN-cats had either anti-GM2 or anti-GalNAc-GD1a IgG antibodies, with 24/29 cats having both. Direct comparison of anti-GM2 (sensitivity: 70.7%; specificity: 78.2%) and anti-GalNAc-GD1a (sensitivity: 70.7%; specificity: 70.9%) antibodies narrowly showed anti-GM2 IgG antibodies to be the better marker for identifying IPN-cats when compared to the combined ONM and CTRL groups (P = .049). Anti-GA1 and/or anti-sulphatide IgG antibodies were ubiquitously present across all sample groups, whereas antibodies against GM1, GD1a, GD1b, SGPG, LM1 and galactocerebroside were overall only rarely observed. Anti-GM2 and anti-GalNAc-GD1a IgG antibodies may serve as serum biomarkers for immune-mediated polyneuropathies in cats, as previously observed in dogs and humans.

The effects of sugammadex vs. neostigmine on postoperative respiratory complications and advanced healthcare utilisation: a multicentre retrospective cohort study

Reversing neuromuscular blockade with sugammadex can eliminate residual paralysis, which has been associated with postoperative respiratory complications. There are equivocal data on whether sugammadex reduces these when compared with neostigmine. We investigated the association of the choice of reversal drug with postoperative respiratory complications and advanced healthcare utilisation. We included adult patients who underwent surgery and received general anaesthesia with sugammadex or neostigmine reversal at two academic healthcare networks between January 2016 and June 2021. The primary outcome was postoperative respiratory complications, defined as post-extubation oxygen saturation < 90%, respiratory failure requiring non-invasive ventilation, or tracheal re-intubation within 7 days. Our main secondary outcome was advanced healthcare utilisation, a composite outcome including: 7-day unplanned intensive care unit admission; 30-day hospital readmission; or non-home discharge. In total, 5746 (6.9%) of 83,250 included patients experienced postoperative respiratory complications. This was not associated with the reversal drug (adjusted OR (95%CI) 1.01 (0.94-1.08); p = 0.76). After excluding patients admitted from skilled nursing facilities, 8372 (10.5%) patients required advanced healthcare utilisation, which was not associated with the choice of reversal (adjusted OR (95%CI) 0.95 (0.89-1.01); p = 0.11). Equivalence testing supported an equivalent effect size of sugammadex and neostigmine on both outcomes, and neostigmine was non-inferior to sugammadex with regard to postoperative respiratory complications or advanced healthcare utilisation. Finally, there was no association between the reversal drug and major adverse cardiovascular events (adjusted OR 1.07 (0.94-1.21); p = 0.32). Compared with neostigmine, reversal of neuromuscular blockade with sugammadex was not associated with a reduction in postoperative respiratory complications or post-procedural advanced healthcare utilisation.

Serum anti-GM2 and anti-GalNAc-GD1a IgG antibodies are biomarkers for acute canine polyradiculoneuritis

OBJECTIVES

A previous single-country pilot study indicated serum anti-GM2 and anti-GA1 anti-glycolipid antibodies as potential biomarkers for acute canine polyradiculoneuritis. This study aims to validate these findings in a large geographically heterogenous cohort.

MATERIALS AND METHODS

Sera from 175 dogs clinically diagnosed with acute canine polyradiculoneuritis, 112 dogs with other peripheral nerve, cranial nerve or neuromuscular disorders and 226 neurologically normal dogs were screened for anti-glycolipid antibodies against 11 common glycolipid targets to determine the immunoglobulin G anti-glycolipid antibodies with the highest combined sensitivity and specificity for acute canine polyradiculoneuritis.

RESULTS

Anti-GM2 anti-glycolipid antibodies reached the highest combined sensitivity and specificity (sensitivity: 65.1%, 95% confidence interval 57.6 to 72.2%; specificity: 90.2%, 95% confidence interval 83.1 to 95.0%), followed by anti-GalNAc-GD1a anti-glycolipid antibodies (sensitivity: 61.7%, 95% confidence interval 54.1 to 68.9%; specificity: 89.3%, 95% confidence interval 82.0 to 94.3%) and these anti-glycolipid antibodies were frequently present concomitantly. Anti-GA1 anti-glycolipid antibodies were detected in both acute canine polyradiculoneuritis and control animals. Both for anti-GM2 and anti-GalNAc-GD1a anti-glycolipid antibodies, sex was found a significantly associated factor with a female to male odds ratio of 2.55 (1.27 to 5.31) and 3.00 (1.22 to 7.89), respectively. Anti-GalNAc-GD1a anti-glycolipid antibodies were more commonly observed in dogs unable to walk (OR 4.56, 1.56 to 14.87).

CLINICAL SIGNIFICANCE

Anti-GM2 and anti-GalNAc-GD1a immunoglobulin G anti-glycolipid antibodies represent serum biomarkers for acute canine polyradiculoneuritis.

Comparison of Dorsal-to-Ventral Ratios of the Cervical Paraspinal Musculature in French Bulldogs With and Without Cervical Intervertebral Disk Disease and Two Other Breeds Based on CT Scan Measurements

Objective: To objectively assess the cervical paraspinal musculature of French bulldogs (FBs) using computed tomography (CT) scan-based measurements, outline differences in other breeds published in the literature, and investigate the potential influence of its cervical paraspinal musculature on predisposed sites for intervertebral disk disease.

Animals: Thirty FBs that underwent CT scans of the cervical spine from the skull to C7/T1 were enrolled. Fifteen dogs were patients suffering from intervertebral disk herniation (IVDH group), and 15 dogs underwent CT scans due to brachycephalic obstructive airway syndrome (BOAS group).

Methods: At the level of each cervical intervertebral disk from C2/C3 to C7/T1, measurements were performed and statistically analyzed. On the sagittal CT scan reconstruction, the height ratio of the dorsal to ventral paraspinal musculature and the angle of the disk axis to vertebral body length were assessed. On the transverse plane, the area ratio of the dorsal and ventral paraspinal musculature and the ratio of force moments were determined at each intervertebral disk level. Finally, ratios were compared to the values of Labrador retrievers and dachshunds published by Hartmann et al. (1).

Results: Comparing the two FB groups, one significant difference was detected in the mean height ratio of the dorsal to ventral paraspinal musculature at the level of C5/C6 (P = 0.0092) and C6/C7 (P = 0.0076), with IVDH FBs having the more prominent dorsal paraspinal musculature. At the level of C3/C4, a significantly less prominent dorsal paraspinal musculature in FBs than in dachshunds (P = 0.0058) and a significantly steeper disk to vertebral body angulation were observed (P = 0.0005).

Conclusion: Although some incidental differences were found, most parameters did not significantly differ between the BOAS and IVDH FBs. Significant conformational differences in the cervical paraspinal musculature and disk to vertebral body length angulation were found between FBs and two other breeds (chondrodystrophic and non-chondrodystrophic). This study's findings suggest that the paraspinal musculature is an additional biomechanical influencing factor on the preferential sites of IVDH in the cervical spine and that other major factors exist in IVDH development, especially in FBs.

Investigation of timing of surgery and other factors possibly influencing outcome in dogs with acute thoracolumbar disc extrusion: a retrospective study of 1501 cases

BACKGROUND

Intervertebral disc extrusions in the thoracolumbar region are a common spinal neurologic disorder in dogs and usually considered a neurological emergency. Several factors, like timing of surgery, have previously been analysed in order to determine the effect on outcome and time of recovery. Most studies have investigated one defined population of dogs and the influence of a single factor on the overall outcome. In this retrospective study, a large cohort of dogs and the influence of one or combinations of several factors on outcome and time of recovery were analysed.

RESULTS

The bivariate analysis demonstrated a significant association between the following variables and the time of recovery: the time span between the onset of clinical signs and surgery (Cramers Phi [Formula: see text] = 0.14; P = 0.003), the grade of severity ([Formula: see text] = 0.23; P < 0.001) and the implementation of physical rehabilitation ([Formula: see text] = 0.2; P < 0.001). However, the analysis of a multivariable regression model demonstrated that a significant correlation only exists between the time span between the onset of clinical signs and surgery and the overall outcome (P = 0.007), as well as between the grade of severity and the time of recovery (P < 0.001). The percentage of dogs with lacking deep pain perception (DPP) that had to be euthanised due to their neurological condition, decreased from 20.0 to 2.9% when physical rehabilitation was implemented. Additionally, the proportion of dogs (same group) that improved to reach an ambulatory status increased from 80.0 to 91.4%.

CONCLUSION

The results of the bivariate analysis demonstrated several correlations between some variables and overall outcome or time of recovery, whereas the multivariable regression model demonstrated only two associations. The time span between the onset of clinical signs and surgery was significantly associated with the overall outcome. We therefore suggest that a surgical intervention should be performed without unreasonable delay. Due to the correlation between the grade of severity and time of recovery, owners of dogs with more severe neurological deficits prior to surgery should be informed about the presumably prolonged time of recovery.

The p.Ala2430Val mutation in filamin C causes a "hypertrophic myofibrillar cardiomyopathy"

Hypertrophic cardiomyopathy (HCM) often leads to heart failure. Mutations in sarcomeric proteins are most frequently the cause of HCM but in many patients the gene defect is not known. Here we report on a young man who was diagnosed with HCM shortly after birth. Whole exome sequencing revealed a mutation in the FLNC gene (c.7289C > T; p.Ala2430Val) that was previously shown to cause aggregation of the mutant protein in transfected cells. Myocardial tissue from patients with this mutation has not been analyzed before and thus, the underlying etiology is not well understood. Myocardial tissue of our patient obtained during myectomy at the age of 23 years was analyzed in detail by histochemistry, immunofluorescence staining, electron microscopy and western blot analysis. Cardiac histology showed a pathology typical for myofibrillar myopathy with myofibril disarray and abnormal protein aggregates containing BAG3, desmin, HSPB5 and filamin C. Analysis of sarcomeric and intercalated disc proteins showed focally reduced expression of the gap junction protein connexin43 and Xin-positive sarcomeric lesions in the cardiomyocytes of our patient. In addition, autophagy pathways were altered with upregulation of LC3-II, WIPI1 and HSPB5, 6, 7 and 8. We conclude that the p.Ala2430Val mutation in FLNC most probably is associated with HCM characterized by abnormal intercalated discs, disarray of myofibrils and aggregates containing Z-disc proteins similar to myofibrillar myopathy, which supports the pathological effect of the mutation.

Single Nuclei Sequencing Reveals Novel Insights Into the Regulation of Cellular Signatures in Children With Dilated Cardiomyopathy

BACKGROUND

Dilated cardiomyopathy (DCM) is a leading cause of death in children with heart failure. The outcome of pediatric heart failure treatment is inconsistent, and large cohort studies are lacking. Progress may be achieved through personalized therapy that takes age- and disease-related pathophysiology, pathology, and molecular fingerprints into account. We present single nuclei RNA sequencing from pediatric patients with DCM as the next step in identifying cellular signatures.

METHODS

We performed single nuclei RNA sequencing with heart tissues from 6 children with DCM with an age of 0.5, 0.75, 5, 6, 12, and 13 years. Unsupervised clustering of 18 211 nuclei led to the identification of 14 distinct clusters with 6 major cell types.

RESULTS

The number of nuclei in fibroblast clusters increased with age in patients with DCM, a finding that was confirmed by histological analysis and was consistent with an age-related increase in cardiac fibrosis quantified by cardiac magnetic resonance imaging. Fibroblasts of patients with DCM >6 years of age showed a profoundly altered gene expression pattern with enrichment of genes encoding fibrillary collagens, modulation of proteoglycans, switch in thrombospondin isoforms, and signatures of fibroblast activation. In addition, a population of cardiomyocytes with a high proregenerative profile was identified in infant patients with DCM but was absent in children >6 years of age. This cluster showed high expression of cell cycle activators such as cyclin D family members, increased glycolytic metabolism and antioxidative genes, and alterations in ß-adrenergic signaling genes.

CONCLUSIONS

Novel insights into the cellular transcriptomes of hearts from pediatric patients with DCM provide remarkable age-dependent changes in the expression patterns of fibroblast and cardiomyocyte genes with less fibrotic but enriched proregenerative signatures in infants.

Single nuclei sequencing reveals novel insights into cardiac cell signatures in human pediatric dilated cardiopathy

 

The mechanism underlying dilated cardiomyopathy (DCM) in children without a known genetic disorder are unclear. In contrast to adult DCM patients, there is an unmet need for therapeutic options that improve survival in pediatric DCM. Therefore, we performed single nuclei RNA sequencing (snRNA-seq) from heart tissue obtained from children undergoing heart transplantation due to severe heart failure.

We processed heart tissue from 6 children with DCM (EF: 18.67±2.11%) of an age of 0.5, 0.75, 5, 6, 12 and 13 years (y). After snRNA-seq, unsupervised clustering was performed identifying 8 major cell types, including cardiomyocytes (CM), fibroblasts (FB), endothelial cells, leukocytes, pericytes, smooth muscle cells, neuronal-like cells and an endothelial-fibroblast-like cluster. Relative numbers of FB clusters correlated with increasing age of the children which was clinically validated by measuring late enhancement (LE) with cardiac magnetic resonance imaging in 68 pediatric DCM patients. The mean age of patients with LE was 5.86±0.53y vs. 2.36±0.53y in patients without LE (p&lt;0.05). Further analysis of unique highly expressed genes (DEGs) between the 3 age groups identified a profound alteration of gene expression in FB clusters. FBs of explants of &lt;1y old patients showed high expression of anti-fibrotic, development and remodeling associated genes. In contrast, FBs of 12–13y old children highly expressed pro-fibrotic and FB activation associated genes as transforming growth factor beta binding protein (6.63 fold), cytochrome P450 1B1 (3.79 fold), and periostin (7.67 fold) (all p&lt;0.05). Moreover, we observed a switch in collagen expression patterns and in thrombospondin isoforms (from THBS1 to THBS4). Furthermore, our analysis revealed most profound transcriptional changes in CMs. We identified a cluster of CMs with a pro-regenerative profile in &lt;1y old patients, which could not be detected during adolescence. This CM cluster showed high expression of genes associated with proliferation (e.g. cyclin D2), glycolytic metabolism and anti-oxidant markers. Increased cyclin D2 was confirmed by immunostaining (1.43 fold higher in &lt;1y vs. 12–13y). Since all of these gene expression patterns might be affected by the underlying disease of the pediatric heart recipients, we explored their expression in FBs and CMs of postnatal vs. adult mice. Importantly, we could recapitulate the vast majority of the findings from humans in the mice experiments.

Together, these data demonstrate an age-dependent decrease in CM numbers concomitant with increased FBs in pediatric DCM. FBs of &lt;1y old pediatric patients revealed a distinct collagen expression profile and showed lower levels of pro-fibrotic genes. CMs of &lt;1y old donors where characterized with a regeneration enabling gene expression profile, which include pro-proliferative genes. The expression patterns of the CMs indicates, that regeneration might also occur in humans during the firs year of life.

Funding Acknowledgement

Type of funding source: Public grant(s) – EU funding. Main funding source(s): Dr. Rolf M. Schwiete Stiftung, DZHK

Does the identification of seniors at risk (ISAR) score effectively select geriatric patients on emergency admission?

The number of older patients admitted to emergency departments (ED) increases continuously. The Identification of Seniors at Risk (ISAR) score is currently recommended to screen patients in German ED, but its appropriateness is being criticized. ISAR scores and clinical characteristics from 98 emergency admissions (EA), 80 from acute geriatrics (AG) and 89 from a geriatric rehabilitation (GR) unit were compared retrospectively. No significant differences were found between groups, being the ISAR score positive in 87.7% of EA, 94.9% of AG and 94.4% of GR cases. None of positively identified geriatric patients in the EA was transferred to the geriatric ward of competence. EA patients showed significantly higher number of functional impairments (p = 0.001) and higher BI score (p < 0.0001) compared to AG and GR groups. A higher ISAR score threshold and additional functional information might be needed to better select patients in need of prompt treatment by a geriatric team.

Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN

We report on the neutrino mass measurement result from the first four-week science run of the Karlsruhe Tritium Neutrino experiment KATRIN in spring 2019. Beta-decay electrons from a high-purity gaseous molecular tritium source are energy analyzed by a high-resolution MAC-E filter. A fit of the integrated electron spectrum over a narrow interval around the kinematic end point at 18.57 keV gives an effective neutrino mass square value of (-1.0_{-1.1}^{+0.9})  eV^{2}. From this, we derive an upper limit of 1.1 eV (90% confidence level) on the absolute mass scale of neutrinos. This value coincides with the KATRIN sensitivity. It improves upon previous mass limits from kinematic measurements by almost a factor of 2 and provides model-independent input to cosmological studies of structure formation.

[Fibromyalgia Syndrome - Impact for Rehabilitation]

Fibromyalgia syndrome (FMS) is one of the most common chronic pain syndromes. In a representative survey, 2.1% of the German population was affected in 2013, whereby the diagnosis can only be made on the basis of subjective complaints. This article should provide concrete information on the disease concept, diagnosis, therapy, rehabilitation and socialmedical assessment at the FMS. The basis for this is the second update of the S3 guideline to the FMS adopted in 2017.

Dysregulated autophagy in restrictive cardiomyopathy due to Pro209Leu mutation in BAG3

Myofibrillary myopathies (MFM) are hereditary myopathies histologically characterized by degeneration of myofibrils and aggregation of proteins in striated muscle. Cardiomyopathy is common in MFM but the pathophysiological mechanisms are not well understood. The BAG3-Pro209Leu mutation is associated with early onset MFM and severe restrictive cardiomyopathy (RCM), often necessitating heart transplantation during childhood. We report on a young male patient with a BAG3-Pro209Leu mutation who underwent heart transplantation at eight years of age. Detailed morphological analyses of the explanted heart tissue showed intracytoplasmic inclusions, aggregation of BAG3 and desmin, disintegration of myofibers and Z-disk alterations. The presence of undegraded autophagosomes, seen by electron microscopy, as well as increased levels of p62, LC3-I and WIPI1, detected by immunohistochemistry and western blot analyses, indicated a dysregulation of autophagy. Parkin and PINK1, proteins involved in mitophagy, were slightly increased whereas mitochondrial OXPHOS activities were not altered. These findings indicate that altered autophagy plays a role in the pathogenesis and rapid progression of RCM in MFM caused by the BAG3-Pro209Leu mutation, which could have implications for future therapeutic strategies.

Cardiac regeneration in children

Very young mammals have an impressive cardiac regeneration capacity. In contrast, cardiac regeneration is very limited in adult humans. The hearts of young children have a higher regenerative capacity compared with adults, as, for example, seen after surgical correction of an anomalous left coronary artery arising from the pulmonary artery or in children with univentricular hearts, who present enormous morphological changes after volume unloading. In addition, the enormous regenerative potential of growing children's hearts is reflected in the spontaneous courses of children with severely deteriorated cardiac function (e.g., patients with dilated cardiomyopathy). The extent of this regenerative capacity and its time dependency remain to be elucidated in the future and should be exploited to improve the treatment of children with severe heart insufficiency.

Systemic arterial endothelial function in children and young adults with idiopathic pulmonary arterial hypertension: is there a relation to pulmonary endothelium-dependent relaxation?

Pulmonary arterial endothelial function is known to be affected in patients with idiopathic pulmonary arterial hypertension (IPAH). Current reports also detected peripheral systemic arterial dysfunction in IPAH patients. The purpose of this study was to assess whether there is a relation between pulmonary arterial and systemic arterial endothelial function. Pulmonary arterial endothelium-dependent relaxation was assessed by changes in pulmonary blood flow in response to acetylcholine which were determined using intravascular Doppler flow measurements. Pulmonary flow reserve (PFR) was calculated as the ratio of pulmonary blood flow velocity in response to acetylcholine relative to baseline values. Systemic arterial endothelial function was assessed by the vascular response to reactive hyperemia, and was recorded non-invasively by peripheral arterial finger tonometry under standardized conditions. Thirteen children and young adults [mean age 16.7 (±5.6) years] with IPAH and 13 age-/gender-matched controls were included in the study. Digital reactive hyperemic index (RHI) of the IPAH patients was 1.54 (±0.69), and of the controls was 1.67 (±0.66) [p = 0.64]. The mean baseline flow velocity in the segmental pulmonary artery of all patients was 18.5 (±5.5) cm/s, increasing to 27.4 (±12.3) cm/s (p = 0.003) during acetylcholine infusion. The calculated mean PFR was 1.48 (±0.4). There was no significant correlation between the PFR and RHI (r = 0.19; p = 0.54). According to our results, systemic arterial endothelial function assessed by peripheral arterial finger tonometry was not significantly impaired in children and young adults with IPAH compared with age-/gender-matched controls. There was no correlation between systemic arterial and pulmonary arterial endothelial function, suggesting that different mechanisms may contribute to their pathogenesis and progression.

[Magnetic resonance imaging features of a caudal cruciate ligament rupture associated with a suspected bone bruise lesion in a dog]

In this case study we describe a surgically confirmed caudal cruciate ligament rupture in a 10-year-old Border Collie. Magnetic resonance imaging (MRI) demonstrated a complete rupture of the caudal cruciate ligament, a suspected bone bruise lesion on the proximolateral tibia and a muscle strain injury of the M. flexor digitorum lateralis. In human medicine, bone bruise lesions in MRI have been described as "footprint injuries" and can thereby explain the mechanism of trauma in ligament injuries. The combination of the MRI findings in this case can help to understand how the rarely diagnosed isolated rupture of the caudal cruciate ligament occurred in this dog.

Cardiovascular magnetic resonance assessment of ventricular function and myocardial scarring before and early after repair of anomalous left coronary artery from the pulmonary artery

BACKGROUND

In patients with anomalous left coronary artery from the pulmonary artery (ALCAPA) left ventricular (LV) dilatation and dysfunction evolves due to diminished myocardial perfusion caused by coronary steal phenomenon. Using late gadolinium enhanced cardiovascular magnetic resonance (LGE-CMR) imaging, myocardial scarring has been shown in ALCAPA patients late after repair, however the incidence of scarring before surgery and its impact on postoperative course after surgical repair remained unknown.

METHODS

8 ALCAPA-patients (mean age 10.0 ± 5.8 months) underwent CMR before and early after (mean 4.9 ± 2.5 months) coronary reimplantation procedures. CMR included functional analysis and LGE for detection of myocardial scars.

RESULTS

LV dilatation (mean LVEDVI 171 ± 94 ml/m2) and dysfunction (mean LV-EF 22 ± 10 %) was present in all patients and improved significantly after surgery (mean LVEDV 68 ± 42 ml/m2, p=0.02; mean LV-EF 58 ± 19 %, p<0.001). Preoperative CMR revealed myocardial scarring in 2 of the 8 patients and did not predict postoperative course. At follow-up CMR, one LGE-positive patient showed delayed recovery of LV function while myocardial scarring was still present in both patients. In two patients new-onset transmural scarring was found, although functional recovery after operation was sufficient. One of them showed a stenosis of the left coronary artery and required resurgery.

CONCLUSIONS

Despite diminished myocardial perfusion and severely compromised LV function, myocardial scarring was preoperatively only infrequently present. Improvement of myocardial function was independent of new-onset scarring while the impact of preoperative scarring still needs to be defined.

Aortopulmonary collateral flow is related to pulmonary artery size and affects ventricular dimensions in patients after the fontan procedure

BACKGROUND

Aortopulmonary collaterals (APCs) are frequently found in patients with a single-ventricle (SV) circulation. However, knowledge about the clinical significance of the systemic-to-pulmonary shunt flow in patients after the modified Fontan procedure and its potential causes is limited. Accordingly, the aim of our study was to detect and quantify APC flow using cardiovascular magnetic resonance (CMR) and assess its impact on SV volume and function as well as to evaluate the role of the size of the pulmonary arteries in regard to the development of APCs.

METHODS

60 patients (mean age 13.3 ± 6.8 years) after the Fontan procedure without patent tunnel fenestration underwent CMR as part of their routine clinical assessment that included ventricular functional analysis and flow measurements in the inferior vena cava (IVC), superior vena cava (SVC) and ascending aorta (Ao). APC flow was quantified using the systemic flow estimator: (Ao) - (IVC + SVC). Pulmonary artery index (Nakata index) was calculated as RPA + LPA area/body surface area using contrast enhanced MR angiography. The patient cohort was divided into two groups according to the median APC flow: group 1 < 0.495 l/min/m(2) and group 2 > 0.495 l/min/m(2).

RESULTS

Group 1 patients had significant smaller SV enddiastolic (71 ± 16 vs 87 ± 25 ml/m(2); p=0.004) and endsystolic volumes (29 ± 11 vs 40 ± 21 ml/m(2); p=0.02) whereas ejection fraction (59 ± 9 vs 56 ± 13%; p=0.38) differed not significantly. Interestingly, pulmonary artery size showed a significant inverse correlation with APC flow (r=-0.50, p=0.002).

CONCLUSIONS

Volume load due to APC flow in Fontan patients affected SV dimensions, but did not result in an impairment of SV function. APC flow was related to small pulmonary artery size, suggesting that small pulmonary arteries represent a potential stimulus for the development of APCs.