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1.
J Fish Biol ; 104(1): 252-264, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37804519

ABSTRACT

This study was the first to investigate the key reproductive traits of the electric lantern fish Electrona risso (Myctophidae, n = 918) and the bigscale fishes (Melamphaidae) Melamphaes polylepis (n = 260) and Scopelogadus mizolepis (n = 649). Specimens of these mesopelagic species were collected in March and April 2015 in the eastern Central Atlantic (0-24° N, 20-26° W). Sex ratio was not significantly different from 1:1 in E. risso and M. polylepis but significantly skewed toward female dominance in S. mizolepis. Reproductive phases were determined macroscopically and by histological analyses on selected individuals. Female length at 50% maturity (L50 ) was 55.1 mm standard length (LS ) in E. risso, with an observed female maximum length (Lmax ) of 81.2 mm LS . M. polylepis females had an L50 of 40.2 mm LS and an Lmax of 86.7 mm LS . S. mizolepis had an L50 of 46 mm LS and an Lmax of 97.9 mm LS . The three species show histological features of iteroparity, but the E. risso population appears to occur in two year-classes and experience only one spawning season per lifetime in the study region. All three species are batch-spawners. A batch fecundity of 2668 eggs was estimated from one E. risso individual, with a relative batch fecundity of 369 eggs g-1 gonad-free body mass. M. polylepis had a batch fecundity of 1027 eggs and a relative batch fecundity of 149 eggs g-1 (n = 3). S. polylepis had a batch fecundity of 1545 eggs and a relative batch fecundity of 215 eggs g-1 (n = 21). The median gonado-somatic index during the actively spawning phase of E. risso was 4.5, significantly lower than that of M. polylepis (7.5) and S. mizolepis (7.1). No regressing or regenerating phases were observed in this study. Batch-spawning in all three species is suggested to be advantageous to cope with intra-annual variability in food supply and other risks for offspring survival. With what appears to be in effect a (facultative) semelparous strategy in combination with a short life span in E. risso, interannual differences would have a great effect on population dynamics of this species. Knowledge is still lacking on temporal aspects of reproduction such as the duration of the spawning season and the frequency of spawning, as well as age and growth.


Subject(s)
Electric Fish , Reproduction , Female , Animals , Fertility , Fishes , Gonads , Seasons , Biology
2.
Heart Rhythm O2 ; 4(6): 382-390, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37361620

ABSTRACT

Background: Implantable cardioverter-defibrillator (ICD) therapy in elderly patients is controversial because survival benefits might be attenuated by nonarrhythmic causes of death. Objective: The purpose of this study was to investigate the outcome of septuagenarians and octogenarians after ICD generator exchange (GE). Methods: A total of 506 patients undergoing elective GE were analyzed to determine the incidence of ICD shocks and/or survival after GE. Patients were divided into a septuagenarian group (age 70-79 years) and an octogenarian group (age ≥80 years). The primary endpoint was death from any cause. Secondary endpoints were survival after appropriate ICD shock and death without experiencing ICD shocks after GE ("prior death"). Results: The association of the ICD with all-cause mortality and arrhythmic death was determined for septuagenarians and octogenarians. Comparing both groups, similar left ventricular ejection fraction (35.6% ± 11.2% vs 32.4% ± 8.9%) and baseline prevalence of New York Heart Association functional class III or IV heart failure (17.1% vs 14.7%) were found. During the entire follow-up period of the study, 42.5% of patients in the septuagenarian group died compared to 79% in the octogenarian group (P <.01). Prior death was significantly more frequent in both age groups than were appropriate ICD shocks. Predictors of mortality were common in both groups and included advanced heart failure, peripheral arterial disease, and renal failure. Conclusion: In clinical practice, decision-making for ICD GE among the elderly should be considered carefully for individual patients.

3.
Sci Data ; 9(1): 483, 2022 08 06.
Article in English | MEDLINE | ID: mdl-35933490

ABSTRACT

Data on marine biota exist in many formats and sources, such as published literature, data repositories, and unpublished material. Due to this heterogeneity, information is difficult to find, access and combine, severely impeding its reuse for further scientific analysis and its long-term availability for future generations. To address this challenge, we present CRITTERBASE, a publicly accessible data warehouse and interactive portal that currently hosts quality-controlled and taxonomically standardized presence/absence, abundance, and biomass data for 18,644 samples and 3,664 benthic taxa (2,824 of which at species level). These samples were collected by grabs, underwater imaging or trawls in Arctic, North Sea and Antarctic regions between the years 1800 and 2014. Data were collated from literature, unpublished data, own research and online repositories. All metadata and links to primary sources are included. We envision CRITTERBASE becoming a valuable and continuously expanding tool for a wide range of usages, such as studies of spatio-temporal biodiversity patterns, impacts and risks of climate change or the evidence-based design of marine protection policies.


Subject(s)
Biodiversity , Biota , Data Warehousing , Arctic Regions , Climate Change , Ecosystem , Oceans and Seas
4.
BMJ Open ; 12(4): e056888, 2022 04 15.
Article in English | MEDLINE | ID: mdl-35428636

ABSTRACT

INTRODUCTION: Acute myocardial infarction (AMI) is a major public health issue in Germany with considerable regional differences in morbidity and mortality. Possible reasons for regional differences include a higher prevalence of cardiovascular risk factors, infrastructural deficits, different levels of healthcare quality or social determinants. We aim to study associations of social determinants and of rural infrastructure with the quality of medical care (eg, time to reperfusion or medication adherence) and on the long-term outcome after myocardial infarction. METHODS AND ANALYSIS: We will employ a prospective cohort study design. Patients who are admitted with AMI will be invited to participate. We aim to recruit a total of 1000 participants over the course of 5 years. Information on outpatient care prior to AMI, acute healthcare of AMI, healthcare-related environmental factors and social determinants will be collected. Baseline data will be assessed in interviews and from the electronic data system of the hospital. Follow-up will be conducted after an observation period of 1 year via patient interviews. The outcomes of interest are cardiac and all-cause mortality, changes in quality of life, changes in health status of heart failure, major adverse cardiovascular events and participation in rehabilitation programmes. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Ethics Committee of Brandenburg Medical School (reference: E-01-20200923). Research findings will be disseminated and shared in different ways and include presenting at international and national conferences, publishing in peer-reviewed journals and facilitating dissemination workshops within local communities with patients and healthcare professionals. TRIALS REGISTRATION NUMBER: DRKS00024463.


Subject(s)
Myocardial Infarction , Quality of Life , Cohort Studies , Humans , Prospective Studies , Social Determinants of Health
5.
J Med Case Rep ; 15(1): 243, 2021 May 17.
Article in English | MEDLINE | ID: mdl-33993888

ABSTRACT

BACKGROUND: The implantation of cardioverter defibrillators (ICDs) is an established therapy in the prevention of sudden cardiac death in patients with systolic dysfunction after myocardial infarction. To avoid immediate implantation of an ICD, wearable cardioverter defibrillator vests (WCD) can be used to protect patients against malignant rhythm disorders, while at the same time drug-based heart failure therapy has to be initiated. This drug therapy can improve left ventricular ejection fraction and primary prophylactic cardioverter defibrillator implantation may not be necessary. However, the recent Vest Prevention of Early Sudden Death Trial (VEST) questioned the regular use of the WCD in this setting. CASE PRESENTATION: A 47-year-old Caucasian man with severely impaired left ventricular function early after myocardial infarction was prescribed a WCD as primary prophylaxis to prevent sudden cardiac death. Seven days after the patient was supplied with a WCD, the patient suffered from an electrical storm with recurrent ventricular tachycardia (VT), which was successfully terminated 17 times by the WCD. On coronary angiography, the formerly infarct-related right coronary artery had TIMI (Thrombolysis in Myocardial Ischemia Trial) III flow, and a remaining stenosis in the left anterior descending artery (LAD) was stented, which did not stop recurrent VT. In the electrophysiology (EP) study, a focus was mapped in the left inferior ventricle, which was ablated. This stopped the VT. A second radio-frequency (RF) ablation in the same area was necessary after 14 days. Finally, a permanent cardioverter defibrillator was implanted. CONCLUSION: We report the case of a patient who survived recurrent episodes of VT early after myocardial infarction by effective defibrillation with a WCD. The WCD is a useful device to bridge time until a final decision for implantation of a defibrillator.


Subject(s)
Defibrillators, Implantable , Myocardial Infarction , Tachycardia, Ventricular , Wearable Electronic Devices , Death, Sudden, Cardiac/prevention & control , Defibrillators , Electric Countershock , Humans , Male , Middle Aged , Myocardial Infarction/complications , Myocardial Infarction/therapy , Stroke Volume , Tachycardia, Ventricular/therapy , Ventricular Function, Left
6.
Healthcare (Basel) ; 9(5)2021 Apr 22.
Article in English | MEDLINE | ID: mdl-33922198

ABSTRACT

(1) Background: Healthcare workers (HCWs) are prone to intensified exposure to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in the ongoing pandemic. We prospectively analyzed the prevalence of antibodies against SARS-CoV-2 in HCWs at baseline and follow up with regard to clinical signs and symptoms in two university hospitals in Brandenburg, Germany. (2) Methods: Screening for anti-SARS-CoV-2 IgA and IgG antibodies was offered to HCWs at baseline and follow up two months thereafter in two hospitals of Brandenburg Medical School during the first wave of the COVID-19 pandemic in Germany in an ongoing observational cohort study. Medical history and signs and symptoms were recorded by questionnaires and analyzed. (3) Results: Baseline seroprevalence of anti-SARS-CoV-2 IgA was 11.7% and increased to 15% at follow up, whereas IgG seropositivity was 2.1% at baseline and 2.2% at follow up. The rate of asymptomatic seropositive cases was 39.5%. Symptoms were not associated with general seropositivity for anti-SARS-CoV-2; however, class switch from IgA to IgG was associated with increased symptom burden. (4) Conclusions: The seroprevalence of antibodies against SARS-CoV-2 was low in HCWs but higher compared to population data and increased over time. Screening for antibodies detected a significant proportion of seropositive participants cases without symptoms.

7.
Cardiology ; 146(2): 213-221, 2021.
Article in English | MEDLINE | ID: mdl-33550300

ABSTRACT

BACKGROUND: Arrhythmia and sudden cardiac death (SCD) are known complications of acute viral myocarditis, regardless of ejection fraction (EF) at presentation. Whether such complications confer long-term risk is unknown, especially in those who present with preserved left ventricular (LV) function. No guidelines exist to the long-term reduction of arrhythmic death in such patients. METHOD: In this retrospective study, we analyzed the long-term results of implantable cardioverter defibrillator (ICD) treatment in patients after an acute phase of myocarditis with life-threatening arrhythmia. RESULTS: We identified 51 patients who had ICDs implanted following life-threatening arrhythmia presentation of confirmed acute viral myocarditis, despite preserved LVEF. Overall, 72.5% of patients had a clinical history of chest pain and viral infection with fever. Viral myocarditis was confirmed by cardiac magnetic resonance imaging (all had late enhancement) plus endomyocardial biopsies (most frequent were Epstein-Barr virus 29.4%, adenovirus 17.6%, and Coxsackie 17.6%), and 88.2% were discharged on anti-arrhythmic drugs. Overall, 12 patients (23.5%) required ICD intervention within the first 3 months, a further 7 patients (37.3% overall) between 3 and 12 months, and a further 12 patients (60.8% overall) until 58 months. During the follow-up, 3 of 51 patients (5.9%) died-deaths were due to cardiac events (n = 1), fatal infection (n = 1), and car accidents (n = 1). Of the 31 patients who had ventricular tachycardias after the acute phase of myocarditis, 11 needed radiofrequency ablation due to a high number of events or electrical storm. No baseline variables were identified that would serve as a basis for risk stratification. CONCLUSION: Malignant arrhythmic events due to viral myocarditis are potential predictors of future SCD in patients not only with a reduced but also with a preserved EF.


Subject(s)
Defibrillators, Implantable , Epstein-Barr Virus Infections , Myocarditis , Arrhythmias, Cardiac/therapy , Biopsy , Death, Sudden, Cardiac/prevention & control , Herpesvirus 4, Human , Humans , Myocarditis/therapy , Retrospective Studies , Risk Factors , Secondary Prevention , Stroke Volume
8.
PLoS One ; 9(8): e102491, 2014.
Article in English | MEDLINE | ID: mdl-25105293

ABSTRACT

We investigated density-dependent mortality within the early months of life of the bivalves Macoma balthica (Baltic tellin) and Cerastoderma edule (common cockle) in the Wadden Sea. Mortality is thought to be density-dependent in juvenile bivalves, because there is no proportional relationship between the size of the reproductive adult stocks and the numbers of recruits for both species. It is not known however, when exactly density dependence in the pre-recruitment phase occurs and how prevalent it is. The magnitude of recruitment determines year class strength in bivalves. Thus, understanding pre-recruit mortality will improve the understanding of population dynamics. We analyzed count data from three years of temporal sampling during the first months after bivalve settlement at ten transects in the Sylt-Rømø-Bay in the northern German Wadden Sea. Analyses of density dependence are sensitive to bias through measurement error. Measurement error was estimated by bootstrapping, and residual deviances were adjusted by adding process error. With simulations the effect of these two types of error on the estimate of the density-dependent mortality coefficient was investigated. In three out of eight time intervals density dependence was detected for M. balthica, and in zero out of six time intervals for C. edule. Biological or environmental stochastic processes dominated over density dependence at the investigated scale.


Subject(s)
Bivalvia/physiology , Mortality , Age Factors , Animals , Computer Simulation , Linear Models , Netherlands , Oceans and Seas , Population Density , Regression Analysis , Research Design , Species Specificity
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