Phosphoproteome analysis of the crosstalk between sumoylation and phosphorylation in mouse spermatocytes.

Spermatogenesis is supported by various posttranslational modifications. There is growing evidence supporting a crosstalk between sumoylation and phosphorylation in different cell types. We have recently shown that inhibition of global sumoylation with a sumoylation inhibitor (Ginkgolic acid, GA) arrested purified mouse spermatocytes in vitro; the spermatocytes could not condense chromatin and disassemble the synaptonemal complex. Our data have also revealed that some kinases regulating the meiotic prophase (PLK1 and AURKB) were inhibited upon the inhibition of sumoylation. Nevertheless, specific phosphorylated targets affected by the inhibition of sumoylation have not been identified. To address this gap, in this study, we performed a comparative phospho-proteome analysis of the control spermatocytes and spermatocytes treated with the GA. Our analysis has narrowed down to several proteins implicated in the regulation of cell cycle and/or meiosis. Two of these targets, NPM1 and hnRNPH1, were studied further using western blotting in both cell lines and primary cells. Decrease in sumoylaion-dependend phosphorylation of NPM1 on Ser125 regulated by AURKB can be a contributing factor to the inability of spermatocytes to condense chromatin by the end of the prophase and should be studied further.

Retrospective evaluation of hypersensitivity reactions and anaphylaxis in dogs (2003-2014): 86 cases.

OBJECTIVE: To characterize anaphylactic reactions in dogs, including clinical signs, severity, treatments, prognosis, and estimated incidence. To determine whether glucocorticoids influence clinical recovery and survival. DESIGN: Retrospective study between January 1, 2003 and April 28, 2014. SETTING: University teaching hospital. ANIMALS: Eighty-six dogs treated for a type I hypersensitivity reaction. Nineteen dogs fulfilled the criteria for anaphylaxis, and 67 dogs had mild cutaneous reactions. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The estimated incidence was 0.04% for anaphylaxis and 0.15% for mild hypersensitivity reactions. The female:male ratio (2.3:1) was significantly higher (P = 0.032) compared to our source population (ratio of 1:1.158). Vaccines were the most frequent trigger for anaphylaxis (57.9%) and mild hypersensitivity reactions (28.4%). Seventy-four (86%) dogs had cutaneous signs, and 11 (57.9%) dogs with anaphylaxis had no cutaneous signs reported. Forty-two (48.8%) dogs received both an H1 antagonist and a glucocorticoid, 34 (39.5%) dogs received an H1 antagonist only, and 6 (6.9%) dogs received a glucocorticoid only. The majority of the dogs survived, and 1 was euthanized due to complications. Clinical signs associated with nonsurvival included respiratory signs (P = 0.006), particularly respiratory distress (P < 0.00001) and cyanosis (P < 0.00001), and circulatory shock (P = 0.005). The analysis of the interaction between etiology, clinical signs, treatment, and outcome did not show any association between pairs of variables. CONCLUSIONS: In the current study, anaphylaxis had a relatively good prognosis, and cutaneous signs were not always present. Based on the present data, the use of glucocorticoids to treat mild type I hypersensitivity reactions and anaphylaxis in dogs was not associated with clinical improvement or survival.

[Conservative management of distal radius fractures]. / Konservative Behandlung der distalen Radiusfraktur.

Distal radius fractures are the third most frequent fractures in Germany. The decision for conservative treatment and the weighing up of surgical treatment need an exact consideration of the indications based on instability criteria and the extent of possible articular involvement. Indications for an emergency operation must be excluded. In cases of stable fractures or multimorbid patients in a poor general condition conservative treatment is indicated. The principles for a successful treatment are the precise reduction and stable retention in a plaster splint. In the further course, fractures are closely monitored by biplanar radiography. This is necessary to rule out a secondary displacement until the swelling of the soft tissues has subsided and the plaster splint is changed to a circular cast approximately 11 days after the traumatic event. The total duration of immobilization is 4 weeks. Physiotherapy and ergotherapy including adjacent joints, starts after 2 weeks of treatment. This treatment is extended to the wrist after removal of the circular cast.

A spatiotemporal machine learning approach to forecasting COVID-19 incidence at the county level in the USA.

With COVID-19 affecting every country globally and changing everyday life, the ability to forecast the spread of the disease is more important than any previous epidemic. The conventional methods of disease-spread modeling, compartmental models, are based on the assumption of spatiotemporal homogeneity of the spread of the virus, which may cause forecasting to underperform, especially at high spatial resolutions. In this paper, we approach the forecasting task with an alternative technique-spatiotemporal machine learning. We present COVID-LSTM, a data-driven model based on a long short-term memory deep learning architecture for forecasting COVID-19 incidence at the county level in the USA. We use the weekly number of new positive cases as temporal input, and hand-engineered spatial features from Facebook movement and connectedness datasets to capture the spread of the disease in time and space. COVID-LSTM outperforms the COVID-19 Forecast Hub's Ensemble model (COVIDhub-ensemble) on our 17-week evaluation period, making it the first model to be more accurate than the COVIDhub-ensemble over one or more forecast periods. Over the 4-week forecast horizon, our model is on average 50 cases per county more accurate than the COVIDhub-ensemble. We highlight that the underutilization of data-driven forecasting of disease spread prior to COVID-19 is likely due to the lack of sufficient data available for previous diseases, in addition to the recent advances in machine learning methods for spatiotemporal forecasting. We discuss the impediments to the wider uptake of data-driven forecasting, and whether it is likely that more deep learning-based models will be used in the future.

Lessons learned during the sliding gantry CT implementation in a trauma suite.

PURPOSE: Early detection of bleeding is important for managing trauma cases in the emergency department (ED). Several trauma suites are equipped with computed tomography (CT) scanners to reduce the time to CT. In the last decade, sliding gantry CT has been implemented in trauma suites, highlighting conventional techniques' advantages. We investigated the change in the time to CT and the challenges faced during the implementation. METHODS: Trauma suite treatments with a conventional CT scanner between January and December 2016 formed the control group. From January to April 2017, trauma suites were modified, and treatment was outsourced to an interim trauma suite. By May 2017, trauma suites were equipped with a sliding gantry CT scanner. Treatments from May to July 2017 formed the transition group, and those from August to December 2017 formed the routine use group. We evaluated the time to CT in all groups and considered the reasons for the delays in the transition and routine use groups. RESULTS: On sliding gantry CT implementation, although time to CT remained unaffected in the transition group, it significantly reduced in the routine use group, independent of injury severity score. The incidence of cable management problems was significantly higher in the latter group. CONCLUSIONS: We have demonstrated a decrease in the time to CT with the implementation of a sliding gantry CT. However, due to a higher number of cable management problems in the routine use group, we recommend regular refresher team training with routine use.

The unequal impact of Covid-19 on the lives and rights of the children of modern slavery survivors, children in exploitation and children at risk of entering exploitation.

This article discusses the unequal impact of Covid-19 on the lives of the children of survivors of modern slavery, child victims of exploitation and children at risk of exploitation in the UK. It draws on research that has analysed the risks and impacts of Covid-19 on victims and survivors of modern slavery. It explores how pandemic responses may have hindered these children's rights to education, food, safety, development and participation and representation in legal processes. It suggests that the pandemic should be used as an impetus to address inequalities that existed pre-Covid-19 and those that have been exacerbated by it.

The impact of a qualified medical documentation assistant on trauma room management.

PURPOSE: To improve quality of trauma room management, intra- and inter-hospital benchmarking are important tools. However, primary data quality is crucial for benchmarking reliability. In this study, we analyzed the effect of a medical documentation assistant on documentation completeness in trauma room management in comparison to documentation by physicians involved in direct patient treatment. METHODS: We included all patients treated in the trauma room from 2016/01/01 to 2016/12/31 that were documented with the trauma module of the German Emergency Department Medical Record V2015.1. We divided the data into documentation by medical documentation assistant (DA, 07:00 to 17:00), physician in daytime (PD, 07:00 to 17:00), and physician at night (PN, 17:00 to 07:00). Data were analyzed for completeness (primary outcome parameter) as well as diagnostic intervals. RESULTS: There was a significant increase in complete recorded data for DA (74.5%; IQR 14.5%) compared to PD (26.9%; IQR 18.7%; p < 0.001) and PN (30.8%; IQR 18.9; p < 0.001). The time to whole-body computed tomography (WBCT) significantly decreased for DA (19 min; IQR 8.3) compared to PD (24 min; IQR 12.8; p = 0.007) or PN (24.5 min; IQR 10.0; p = 0.001). CONCLUSION: In presence of a qualified medical documentation assistant, data completeness and time to WBCT improved significantly. Therefore, utilizing a professional DA in the trauma room appears beneficial for data quality and time management.

Prehospital FAST reduces time to admission and operative treatment: a prospective, randomized, multicenter trial.

BACKGROUND: The focused assessment with sonography in trauma (FAST) exam is an established trauma care diagnostic procedure. Ultrasound performed during prehospital care can improve early treatment and management of the patients. In this prospective randomized clinical trial, we wanted to assess whether a pre-hospital FAST (p-FAST) influences pre-hospital strategy and the time to operative treatment. METHODS: We studied 296 trauma victims in a prehospital setting. Inclusion criteria were potential abdominal injuries identified either by clinical examination or suggested by the mechanism of injury. Physician-staffed helicopters and emergency ambulances were equipped with portable ultrasound devices. According to a scheme related to calendar weeks, a clinical exam only (CEX) or a clinical exam together with a p-FAST (CEX-p-FAST) was conducted. Outcome variables were prehospital diagnosis and strategy, the time to admission to the trauma room and to operation theater. The study was approved by the university ethical committee (REB#: 46/06). RESULTS: CEX-p-FAST showed a high sensitivity (94.7%) and specificity (97.6%) in detection of free fluid compared to CEX-only (80.0%, 84.4%). The median time to admission was reduced significantly by 13 min and to operative treatment by 15 min after CEX-p-FAST. We observed a cross-over rate of 30.8% of p-FAST (n = 36) to CEX-p-FAST during the CEX-only weeks. CONCLUSION: According to the experience of the principal investigators, CEX-p-FAST was superior to CEX-only. Despite the time needed for p-FAST, the relevant admission time was significantly shorter. Thus, p-FAST is recommended in addition to CEX if possible for decision-making in prehospital trauma care. TRIAL REGISTRATION: German Clinical Trials Register #DRKS00022117-Registered 10 July 2020-Retrospectively registered, https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00022117 .

Effects of Gynostemma pentaphyllum on spinal cord motor neurons and microglial cells in vitro.

The regenerative capability of spinal cord neurons is limited to impossible. Thus, experimental approaches supporting reconstruction/regeneration are in process. This study focused on the evaluation of the protective potency of an extract from Gynostemma pentaphyllum (GP), a plant used in traditional medicine with anti-oxidative and neuroprotective activities, in vitro on organotypic spinal cord cultures, the motor-neuron-like NSC-34 cell line and the microglial cell line BV-2. Organotypic cultures were mechanically stressed by the slicing procedure and the effect of GP on motor neuron survival and neurite sprouting was tested by immunohistochemistry. NSC-34 cells were neuronal differentiated by using special medium. Afterwards, cell survival (propidium iodide/fluorescein diacetate labeling), proliferation (BrdU-incorporation), and neurite sprouting were evaluated. BV-2 cells were stimulated with LPS/interferon γ and subjected to migration assay and nanoparticle uptake. Cell survival, proliferation and the expression pattern of different microglial activation markers (cFOS, iNOS) as well as transcription factors (PPARγ, YB1) were analyzed. In organotypic cultures, high-dose GP supported survival of motor neurons and especially of the neuronal fiber network. Despite reduced neurodegeneration, however, there was a GP-mediated activation of astro- and microglia. In NSC-34 cells, high-dosed GP had degenerative and anti-proliferative effects, but only in normal medium. Moreover, GP supported the neuro-differentiation ability. In BV-2 cells, high-dosed GP was toxic. In lower dosages, GP affected cell survival and proliferation when combined with LPS/interferon γ. Nanoparticle uptake, migration ability, and the transcription factor PPARγ, however, GP affected directly. The data suggest positive effects of GP on injured spinal motor neurons. Moreover, GP activated microglial cells. The dual role of microglia (protective/detrimental) in neurodegenerative processes required further experiments to enhance the knowledge about GP effects. Therefore, a possible clinical use of GP in spinal cord injuries is still a long way off.

Effect of 4DryField® PH on blood loss in hip bipolar hemiarthroplasty following intracapsular femoral neck fracture - a randomized clinical trial.

BACKGROUND: One of the most common complications of hip arthroplasty is excessive blood loss that could necessitate allogenic blood transfusion, which is further associated with other complications, such as infections, transfusion reactions or immunomodulation. In gynecology, 4DryField®PH, an absorbable polysaccharide-based formulation, is used for hemostasis and adhesion prophylaxis. In this study, we evaluated its hemostatic effect in patients undergoing hip bipolar hemiarthroplasty following intracapsular femoral neck fracture. METHODS: We studied 40 patients with intracapsular femoral neck fractures (Garden III or IV) admitted at our institution between July 2016 and November 2017. We included patients above 60 years with simple fracture and without pathologic fractures. Patients were randomized into intervention and control groups. The intervention group received 5 g of 4DryField® PH (subfascially and subcutaneously) during wound closure. Three drainages were inserted in a standardized manner (submuscular, subfascial, and subcutaneous) and drainage volume was measured immediately before extraction. Total blood loss was calculated using Mercuriali's formula and standard hemograms upon admission and five days after surgery. Volume of postoperative hematoma was measured using point-of-care ultrasound seven days after surgery. RESULTS: Volume of the postoperative hematoma was reduced by 43.0 mL. However, significant reduction of total blood loss and drainage volume was not observed. CONCLUSIONS: We observed that 4DryField® PH had a local hemostatic effect, thereby reducing volume of the postoperative hematoma. However, this reduction was small and had no effect on the total blood loss. Further studies are warranted to improve the application algorithm. TRIAL REGISTRATION: DRKS, DRKS00017452 , Registered 11 June 2019 - Retrospectively registered.

Existence and role of standard operating procedures in the emergency department : A national online survey.

BACKGROUND: In recent years, increases in the number of patients in emergency departments (ED) have led to continuous work intensification. To handle this problem, the treatment effectiveness has to be maximized. One strategy that may help to optimize workflow is the use of standard operating procedures (SOPs). We investigated the existence of SOPs and subjective effects on treatment in German EDs. METHODS: We performed an online survey from February 2015 until June 2016. We collected data regarding the existence of SOPs, health care level, medical field, work experience, and education. All professional groups participating in the treatment of patients were requested to take part in the survey. RESULTS: Seventy-five percent of the 589 participants in the survey confirmed the existence of SOPs in their EDs. SOPs were more frequently available in hospitals with higher health care levels. Participants working in EDs without SOPs felt less confident regarding treatment of patients. More than 85% of these participants were in favor of having SOPs. The absence of SOPs was associated with a subjective delay in patient treatment. CONCLUSION: Most of the EDs had available SOPs. In departments without SOPs, most physicians wanted them to be implemented. SOPs seemed adequate in terms of supporting workflow and satisfaction with patients' treatment.

Differentiation of NSC-34 cells is characterized by expression of NGF receptor p75, glutaminase and NCAM L1, activation of mitochondria, and sensitivity to fatty acid intervention.

Motor neuronal damage due to diseases, traumatic insults or de-afferentation of the spinal cord is often incurable because of poor intrinsic regenerative capacity. Hence, medical basic research has to provide a better understanding of development-/regeneration-related cellular processes as only way to develop new and successful therapeutic strategies. Here, we investigated the neuronal differentiation of the NSC-34 hybrid cell line, which is an accepted model for spinal cord motor neurons. Their differentiation was stimulated by switching from normal to differentiation medium and by supplementation with palmitic and oleic acid. To characterize neuro-differentiation of NSC-34 cells, expression of nicotinic acetylcholine receptor alpha 4, NGF p75 receptor, IGF I alpha receptor, glutaminase, NCAM L1, ADAM10 and myelin basic protein as well as activation of mitochondria were analyzed. Both switch from normal to differentiation medium and fatty acid application stimulated NSC-34 differentiation. Differentiation was characterized by diminishing expression of the nicotinic acetylcholine receptor alpha 4 and enhancing expression of the NGF receptor p75, of glutaminase, of NCAM L1 and it's partially transformation from the cell surface into the cell. Fatty acid intervention stabilized the expression of the nicotinic acetylcholine receptor alpha 4, diminished the expression of the NGF receptor p75, consolidated the expression profile of NCAM L1, and intensified the expression of the relevant for NCAM L1 cleavage ADAM10. However, NCAM L1 cleavage itself was unaffected by fatty acid intervention, as was the differentiation-relevant activation of mitochondria and their transformation into neuronal filopodia.

Identification of sumoylated targets in proliferating mouse spermatogonia and human testicular seminomas.

Spermatogenesis is regulated by a complex network of posttranslation modifications. Sumoylation (a modification by small ubiquitin-like modifiers, or SUMO proteins) was identified as an important cellular event in different cell types. SUMO proteins are highly expressed in the testis, and their role during spermatogenesis has begun to be elucidated. Given the important role of sumoylation in the regulation of mitosis and cancer progression in other tissues, the aim of the current study was to identify the targets of SUMO in proliferating mouse spermatogonia and human seminoma tissues and to initially examine the level of sumoylation in relation to the proliferative activity of the tissues. Using freshly purified spermatogonia and C18-4 spermatogonia cell line, mass spectrometry analysis identified several SUMO targets implicated into the proliferation of spermatogonia (such as heat shock protein 60 [HSP60] and prohibitin). Tissue array and western blot approaches showed that SUMO expression is a prominent feature of human seminomas and that the proliferative activity of the tumor tissues was positively correlated with the level of SUMO expression. Downregulation of sumoylation with si-RNA was not sufficient to significantly affect the proliferation of C18-4 spermatogonia; however, SUMO overexpression increased the proliferation rate of the cells. These data suggest that cells are more sensitive to an elevated level of SUMO, and that this situation may lead to an upregulated cellular proliferation and, possibly, cancer. Mass spectrometry analysis identified around a hundred SUMO targets in seminoma samples. Notably, many of the identified proteins (such as proliferating cell nuclear antigen [PCNA], DNA topoisomerase 2-alpha [Top2A], prohibitin, 14-3-3 protein, and others) were implicated in oncogenic transformation and cancer progression.

Normoxic post-ROSC ventilation delays hippocampal CA1 neurodegeneration in a rat cardiac arrest model, but does not prevent it.

The European Resuscitation Guidelines recommend that survivors of cardiac arrest (CA) be resuscitated with 100% O2 and undergo subsequent-post-return of spontaneous circulation (ROSC)-reduction of O2 supply to prevent hyperoxia. Hyperoxia produces a "second neurotoxic hit," which, together with the initial ischemic insult, causes ischemia-reperfusion injury. However, heterogeneous results from animal studies suggest that normoxia can also be detrimental. One clear reason for these inconsistent results is the considerable heterogeneity of the models used. In this study, the histological outcome of the hippocampal CA1 region following resuscitation with 100% O2 combined with different post-ROSC ventilation regimes (21%, 50%, and 100% O2) was investigated in a rat CA/resuscitation model with survival times of 7 and 21 days. Immunohistochemical stainings of NeuN, MAP2, GFAP, and IBA1 revealed a neuroprotective potency of post-ROSC ventilation with 21% O2, although it was only temporary. This limitation should be because of the post-ROSC intervention targeting only processes of ischemia-induced secondary injury. There were no ventilation-dependent effects on either microglial activation, reduction of which is accepted as being neuroprotective, or astroglial activation, which is accepted as being able to enhance neurons' resistance to ischemia/reperfusion injury. Furthermore, our findings verify the limited comparability of animal studies because of the individual heterogeneity of the animals, experimental regimes, and evaluation procedures used.

[Patient Motivation to Participate in Medical Education]. / Patientenmotivation zur Mitwirkung in verschiedenen Unterrichts- und Lehrmodalitäten der medizinischen Aus- und Weiterbildung.

BACKGROUND: Student education focuses increasingly on case-related teaching. Often the consent of the patient to participate in student education is supposed to be provided. In most instances this is taken for granted - which it is not. Here, we investigated the motivation of the patients to participate in student education and influence factors using an anonymised survey. MATERIAL AND METHODS: The survey was performed from 2017/01/01 until 2017/04/30 and recruited inpatients of a university department of trauma surgery. The questionnaire contained 10 multiple choice questions targeting socio-demographic factors and the motivation of the patients to participate in different aspects of medical education. This was captured using a 5-point Likert scale. The electronic analysis of the questionnaire was performed with the program KLAUS (Blubbsoft GmbH, Berlin, Germany) after digitalizing the data. RESULTS: In total 162 questionnaires were analysed. The patients were generally highly motivated to participate in bedside teaching and a student examination as well as consenting to the collection of pictures, videos and X-ray images or subsequent contact. Patient satisfaction was a principle factor. There was a positive correlation between the satisfaction with the motivation to participate in bedside teaching and a student examination as well as giving consent to the collection of pictures, videos and X-ray images or subsequent contact. There was significantly decreased motivation for participation in a lecture. In comparison, male patients had greater motivation to participate in a lecture. Moreover 40- to 49-year-old patients were significantly less motivated to participate in a lecture than 20- to 29-year-old and 50- to 59-year-old patients. Patient satisfaction had no influence on motivation to participate in a lecture. CONCLUSION: The motivation of the patients to participate in bedside teaching and a student examination as well as giving consent to the collection of pictures, videos and X-ray images or subsequent contact correlated with patient satisfaction. Socio-demographic factors are less important. Patient motivation to participate in a lecture is lower regardless of patient satisfaction.

Implementation of Emergency Department Performance Benchmarking Using R and LaTeX.

The German Emergency Department Data Registry (GEDD-registry, AKTIN) provides an infrastructure for collecting and querying up-to-date medical records in a distributed manner. Within this framework, a benchmark report on cross-institutional comparison using the program R is prepared using routine data of participating hospitals. Currently, 16 emergency departments (EDs) routinely transfer data of 1,200 to approximately 5,000 patients per month to a federated GEDD-registry datawarehouse. Using various packages in the R environment, hospitals receive a monthly visual report on their data among all participating hospitals. Graphical representations are implemented using column diagrams and box plots. Reports currently contain 25 tables and 40 graphs. Benchmark reports are created in R-Studio and exported using Portable Document Format, PDF. Quarterly expert meetings with the heads of participating EDs are currently performed for further improvements. Preparation of external benchmarking reports with R enables a detailed data presentation for participating hospitals and ED managers.

The way from pen and paper to electronic documentation in a German emergency department.

BACKGROUND: Some of the advantages of implementing electronic emergency department information systems (EDIS) are improvements in data availability and simplification of statistical evaluations of emergency department (ED) treatments. However, for multi-center evaluations, standardized documentation is necessary. The AKTIN project ("National Emergency Department Register: Improvement of Health Services Research in Acute Medicine in Germany") has used the "German Emergency Department Medical Record" (GEDMR) published by the German Interdisciplinary Association of Intensive and Emergency Care as the documentation standard for its national data registry. METHODS: Until March 2016 the documentation standard in ED was the pen-and-paper version of the GEDMR. In April 2016 we implemented the GEDMR in a timeline-based EDIS. Related to this, we compared the availability of structured treatment information of traumatological patients between pen-and-paper-based and electronic documentation, with special focus on the treatment time. RESULTS: All 796 data fields of the 6 modules (basic data, severe trauma, patient surveillance, anesthesia, council, neurology) were adapted for use with the existing EDIS configuration by a physician working regularly in the ED. Electronic implementation increased availability of structured anamnesis and treatment information. However, treatment time was increased in electronic documentation both immediately (2:12 ± 0:04 h; n = 2907) and 6 months after implementation (2:18 ± 0:03 h; n = 4778) compared to the pen-and-paper group (1:43 ± 0:02 h; n = 2523; p < 0.001). CONCLUSIONS: We successfully implemented standardized documentation in an EDIS. The availability of structured treatment information was improved, but treatment time was also increased. Thus, further work is necessary to improve input time.

Mutations in ELAC2 associated with hypertrophic cardiomyopathy impair mitochondrial tRNA 3'-end processing.

Mutations in either the mitochondrial or nuclear genomes are associated with a diverse group of human disorders characterized by impaired mitochondrial respiration. Within this group, an increasing number of mutations have been identified in nuclear genes involved in mitochondrial RNA metabolism, including ELAC2. The ELAC2 gene codes for the mitochondrial RNase Z, responsible for endonucleolytic cleavage of the 3' ends of mitochondrial pre-tRNAs. Here, we report the identification of 16 novel ELAC2 variants in individuals presenting with mitochondrial respiratory chain deficiency, hypertrophic cardiomyopathy (HCM), and lactic acidosis. We provide evidence for the pathogenicity of the novel missense variants by studying the RNase Z activity in an in vitro system. We also modeled the residues affected by a missense mutation in solved RNase Z structures, providing insight into enzyme structure and function. Finally, we show that primary fibroblasts from the affected individuals have elevated levels of unprocessed mitochondrial RNA precursors. Our study thus broadly confirms the correlation of ELAC2 variants with severe infantile-onset forms of HCM and mitochondrial respiratory chain dysfunction. One rare missense variant associated with the occurrence of prostate cancer (p.Arg781His) impairs the mitochondrial RNase Z activity of ELAC2, suggesting a functional link between tumorigenesis and mitochondrial RNA metabolism.