[Clinical characteristics and diagnostics of human spongiform encephalopathies: an update]

Human spongiform encephalopathies are rare transmissible neurodegenerative diseases of the brain and the nervous system that are caused by misfolding of the physiological prion protein into a pathological form and its deposition in the central nervous system (CNS). Prion diseases include Creutzfeldt-Jakob disease (CJD, sporadic or familial), Gerstmann-Straussler-Scheinker syndrome (GSS) and fatal familial insomnia (FFI). Prion diseases can be differentiated into three etiological categories: spontaneous (sporadic CJD), inherited (familial CJD, FFI, and GSS) and acquired (variant CJD and iatrogenic CJD). Most cases occur sporadically. Prion diseases can lead to a variety of neurological symptoms and always have an inevitably fatal course. Cerebrospinal fluid analysis and magnetic resonance imaging (MRI) play a crucial role in the diagnostics of prion diseases and may facilitate an early and reliable clinical diagnosis. A causal treatment or specific therapeutic agents are not yet available. In general, a palliative therapeutic concept is indicated.

Effect of SARS-CoV-2 Incidence and Immunisation Rates on Sporadic Creutzfeldt-Jakob Disease Incidence

BACKGROUND

Recent case studies and media outlets have hypothesised an effect of SARS-CoV-2 infection and immunisation on the development or progression of neurodegenerative diseases such as Alzheimer's disease or sporadic Creutzfeldt-Jakob disease (sCJD).

OBJECTIVES

This study aims to identify potential associations of SARS-CoV-2 infections and SARS-CoV-2 immunisation with sCJD incidence, disease duration, and age of onset.

METHOD

We used data from a prospective sCJD surveillance study in Germany (2016-2022) and publicly available datasets of SARS-CoV-2 cases and vaccination numbers in Germany for the years 2020-2022. Associations of SARS-CoV-2 incidence and immunisation rates with sCJD incidence were assessed by comparing quarterly and annual cumulative sCJD incidences in the periods before (2016-2019) and during the pandemic (2020-2022).

RESULTS

We could not identify any time-related effect of SARS-CoV-2 incidence or immunisation rate on the sCJD incidence. Moreover, we did not find any sCJD incidence alterations before and during the SARS-CoV-2 pandemic on a federal or state level. The overall sCJD incidence was within expected ranges in the years 2020-2022. There were no changes in age of onset and clinical disease duration in these years.

CONCLUSIONS

We found no evidence supporting a short-term effect of the pandemic on sCJD incidence. However, considering the extended pre-clinical phase of sCJD, continued surveillance is needed to identify potential future incidence alterations.

Comparative evaluation of clinical and cerebrospinal fluid biomarker characteristics in rapidly and non-rapidly progressive Alzheimer's disease

BACKGROUND

Rapidly progressive forms of Alzheimer's disease (rpAD) are increasingly recognized and may have a prevalence of up to 30% of patients among all patients with Alzheimer's disease (AD). However, insights about risk factors, underlying pathophysiological processes, and clinical characteristics of rpAD remain controversial. This study aimed to gain a comprehensive picture of rpAD and new insights into the clinical manifestation to enable a better interpretation of disease courses in clinical practice as well as in future clinical studies.

METHODS

Patients (n = 228) from a prospective observational study on AD were selected and categorized into rpAD (n = 67) and non-rpAD (n = 161) disease groups. Patients were recruited through the German Creutzfeldt-Jakob disease surveillance center and the memory outpatient clinic of the Göttingen University Medical Center, representing diverse phenotypes of the AD population. Biomarkers and clinical presentation were assessed using standardized protocols. A drop of ≥ MMSE 6 points within 12 months defined rapid progressors.

RESULTS

Lower CSF Amyloid beta 1-42 concentrations (p = 0.048), lower Amyloid beta 42/40 ratio (p = 0.038), and higher Tau/Amyloid-beta 1-42 ratio, as well as pTau/Amyloid-beta 1-42 ratio (each p = 0.004) were associated with rpAD. Analyzes in a subset of the cohort (rpAD: n = 12; non-rpAD: n = 31) showed higher CSF NfL levels in rpAD (p = 0.024). Clinically, rpAD showed earlier impairment of functional abilities (p < 0.001) and higher scores on the Unified Parkinson's Disease Rating Scale III (p < 0.001), indicating pronounced extrapyramidal motor symptoms. Furthermore, cognitive profiles (adjusted for overall cognitive performance) indicated marked deficits in semantic (p = 0.008) and phonematic (0.023) verbal fluency tests as well as word list learning (p = 0.007) in rpAD compared to non-rpAD. The distribution of APOE genotypes did not differ significantly between groups.

CONCLUSIONS

Our results suggest that rpAD is associated with distinct cognitive profiles, earlier occurrence of non-cognitive symptoms, extrapyramidal motoric disturbance, and lower Amyloid-beta 1-42 concentrations in the CSF. The findings may help to characterize a distinct phenotype of rpAD and estimate prognosis based on clinical characteristics and biomarker results. However, an important future goal should be a unified definition for rpAD to enable targeted study designs and better comparability of the results.

Application of real-time quaking-induced conversion in Creutzfeldt-Jakob disease surveillance

BACKGROUND

Evaluation of the application of CSF real-time quaking-induced conversion in Creutzfeldt-Jakob disease surveillance to investigate test accuracy, influencing factors, and associations with disease incidence.

METHODS

In a prospective surveillance study, CSF real-time quaking-induced conversion was performed in patients with clinical suspicion of prion disease (2014-2022). Clinically or histochemically characterized patients with sporadic Creutzfeldt-Jakob disease (n = 888) and patients with final diagnosis of non-prion disease (n = 371) were included for accuracy and association studies.

RESULTS

The overall test sensitivity for sporadic Creutzfeldt-Jakob disease was 90% and the specificity 99%. Lower sensitivity was associated with early disease stage (p = 0.029) and longer survival (p < 0.001). The frequency of false positives was significantly higher in patients with inflammatory CNS diseases (3.7%) than in other diagnoses (0.4%, p = 0.027). The incidence increased from 1.7 per million person-years (2006-2017) to 2.0 after the test was added to diagnostic the criteria (2018-2021).

CONCLUSION

We validated high diagnostic accuracy of CSF real-time quaking-induced conversion but identified inflammatory brain disease as a potential source of (rare) false-positive results, indicating thorough consideration of this condition in the differential diagnosis of Creutzfeldt-Jakob disease. The surveillance improved after amendment of the diagnostic criteria, whereas the incidence showed no suggestive alterations during the COVID-19 pandemic.

Plasma Lipocalin 2 in Alzheimer’s disease: potential utility in the differential diagnosis and relationship with other biomarkers

Background

Lipocalin-2 is a glycoprotein that is involved in various physiological and pathophysiological processes. In the brain, it is expressed in response to vascular and other brain injury, as well as in Alzheimer’s disease in reactive microglia and astrocytes. Plasma Lipocalin-2 has been proposed as a biomarker for Alzheimer’s disease but available data is scarce and inconsistent. Thus, we evaluated plasma Lipocalin-2 in the context of Alzheimer’s disease, differential diagnoses, other biomarkers, and clinical data.

Methods

For this two-center case-control study, we analyzed Lipocalin-2 concentrations in plasma samples from a cohort of n = 407 individuals. The diagnostic groups comprised Alzheimer’s disease (n = 74), vascular dementia (n = 28), other important differential diagnoses (n = 221), and healthy controls (n = 84). Main results were validated in an independent cohort with patients with Alzheimer’s disease (n = 19), mild cognitive impairment (n = 27), and healthy individuals (n = 28).

Results

Plasma Lipocalin-2 was significantly lower in Alzheimer’s disease compared to healthy controls (p < 0.001) and all other groups (p < 0.01) except for mixed dementia (vascular and Alzheimer’s pathologic changes). Areas under the curve from receiver operation characteristics for the discrimination of Alzheimer’s disease and healthy controls were 0.783 (95%CI: 0.712–0.855) in the study cohort and 0.766 (95%CI: 0.627–0.905) in the validation cohort. The area under the curve for Alzheimer’s disease versus vascular dementia was 0.778 (95%CI: 0.667–0.890) in the study cohort. In Alzheimer’s disease patients, plasma Lipocalin2 did not show significant correlation with cerebrospinal fluid biomarkers of neurodegeneration and AD-related pathology (total-tau, phosphorylated tau protein, and beta-amyloid 1-42), cognitive status (Mini Mental Status Examination scores), APOE genotype, or presence of white matter hyperintensities. Interestingly, Lipocalin 2 was lower in patients with rapid disease course compared to patients with non-rapidly progressive Alzheimer’s disease (p = 0.013).

Conclusions

Plasma Lipocalin-2 has potential as a diagnostic biomarker for Alzheimer’s disease and seems to be independent from currently employed biomarkers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13195-021-00955-9.

Baseline Cerebrospinal Fluid α-Synuclein in Parkinson's Disease Is Associated with Disease Progression and Cognitive Decline

Biomarkers are increasingly recognized as tools in the diagnosis and prognosis of neurodegenerative diseases. No fluid biomarker for Parkinson’s disease (PD) has been established to date, but α-synuclein, a major component of Lewy bodies in PD and dementia with Lewy bodies (DLB), has become a promising candidate. Here, we investigated CSF α-synuclein in patients with PD (n = 28), PDD (n = 8), and DLB (n = 5), applying an electrochemiluminescence immunoassay. Median values were non-significantly (p = 0.430) higher in patients with PDD and DLB (287 pg/mL) than in PD (236 pg/mL). A group of n = 36 primarily non-demented patients with PD and PDD was clinically followed for up to two years. A higher baseline α-synuclein was associated with increases in Hoehn and Yahr classifications (p = 0.019) and Beck Depression Inventory scores (p < 0.001) as well as worse performance in Trail Making Test A (p = 0.017), Trail Making Test B (p = 0.043), and the Boston Naming Test (p = 0.002) at follow-up. Surprisingly, higher levels were associated with a better performance in semantic verbal fluency tests (p = 0.046). In summary, CSF α-synuclein may be a potential prognostic marker for disease progression, affective symptoms, and executive cognitive function in PD. Larger-scaled studies have to validate these findings and the discordant results for single cognitive tests in this exploratory investigation.

Plasma neurofilament light chain as a biomarker for Fatal Familial Insomnia

BACKGROUND

Fatal Familial Insomnia is a rare hereditary prion disease associated with the D178N-129M PRNP mutation. Early diagnosis is difficult because the clinical syndrome may overlap with affective disorders. In addition, most known cerebrospinal fluid biomarkers for prion diseases and magnetic resonance imaging do not show a good diagnostic accuracy for Fatal Familial Insomnia. In this context, data on plasma biomarkers are scarce.

METHODS

We analyzed levels of neurofilament light chain, glial fibrillary acidic protein, chitinase-3-like protein 1, calcium-binding protein B, and total Tau protein in six serial plasma samples from a patient with Fatal Familial Insomnia. Subsequently, plasma neurofilament light chain was analyzed in n=25 patients and n=19 controls. The diagnostic accuracy and associations with disease stage and duration were explored.

RESULTS

Among all biomarker candidates in the case study, only neurofilament light chain levels showed a constant evolution and increased over time. It discriminated Fatal Familial Insomnia from controls with an area under the curve of 0.992 (95%CI:0.974 to 1) in the case-control study. Higher concentrations were associated with methionine homozygosity at Codon 129 PRNP (p=0.006), shorter total disease duration (rho=-0.467, p=0.019, 95%CI:-0.790 to -0.015), and shorter time from sampling to death (rho=-0.467, p=0.019, 95%CI -0.773 to -0.019).

CONCLUSION

Plasma neurofilament light chain may be a valuable minimal-invasive diagnostic biomarker for Fatal Familial Insomnia after clinical onset. Most important, stage-related increase and association with disease duration indicate potential as a prognostic marker and as a surrogate marker in clinical trials.

Total and Phosphorylated Cerebrospinal Fluid Tau in the Differential Diagnosis of Sporadic Creutzfeldt-Jakob Disease and Rapidly Progressive Alzheimer’s Disease

Background: CSF total-tau (t-tau) became a standard cerebrospinal fluid biomarker in Alzheimer’s disease (AD). In parallel, extremely elevated levels were observed in Creutzfeldt-Jakob disease (CJD). Therefore, tau is also considered as an alternative CJD biomarker, potentially complicating the interpretation of results. We investigated CSF t-tau and the t-tau/phosphorylated tau181 ratio in the differential diagnosis of sCJD and rapidly-progressive AD (rpAD). In addition, high t-tau concentrations and associated tau-ratios were explored in an unselected laboratory cohort. Methods: Retrospective analyses included n = 310 patients with CJD (n = 205), non-rpAD (n = 65), and rpAD (n = 40). The diagnostic accuracies of biomarkers were calculated and compared. Differential diagnoses were evaluated in patients from a neurochemistry laboratory with CSF t-tau >1250 pg/mL (n = 199 out of 7036). Results: CSF t-tau showed an AUC of 0.942 in the discrimination of sCJD from AD and 0.918 in the discrimination from rpAD. The tau ratio showed significantly higher AUCs (p < 0.001) of 0.992 versus non-rpAD and 0.990 versus rpAD. In the neurochemistry cohort, prion diseases accounted for only 25% of very high CSF t-tau values. High tau-ratios were observed in CJD, but also in non-neurodegenerative diseases. Conclusions: CSF t-tau is a reliable biomarker for sCJD, but false positive results may occur, especially in rpAD and acute encephalopathies. The t-tau/p-tau ratio may improve the diagnostic accuracy in centers where specific biomarkers are not available.

Development of heart failure in long-term survivors of childhood cancer: results from the cvss study

Background

Long-term survivors of childhood cancer (CCS) are at increased risk for cardiovascular sequelae, including heart failure (HF) as the largest non-malignant contributor to excess death. Yet, little is known about the risk factors, mechanisms of cardiac dysfunction and prevalence of different stages of HF in these patients.

Purpose

To investigate the development and prevalence of HF phenotypes in CCS compared to the general population.

Methods

The CVSS study is a prospective single-center cohort study investigating cardiovascular sequelae of CCS. Patients were eligible for the study when they were diagnosed with a neoplasia according to the International Classification of Childhood Cancer (ICCC 3) at an age prior to 15 years between 1980 and 1990, survived more than five years after initial cancer diagnosis and received antineoplastic treatment. Between 2013 and 2016, study individuals underwent a comprehensive, standardized clinical investigation in the CVSS cohort study including echocardiographic examination. HF was categorized as stages A to D according to current HF guidelines of the American Heart Association (AHA). A population-based sample free of cancer (age- and sex matched) serves as control group.

Results

From 1,002 individuals, all CCS with history of chemo- or radiotherapy and no subsequent neoplasia (n=877) were included (mean age 34.2 (±5.5) years, 44.7% (N=392) female). Age at diagnosis was 6.28 years (±4.24) and the mean interval from the date of diagnosis of cancer to the date of completion of baseline examination 28.5±3.2 years. Based on echocardiographic examination, clinical data and biomarker assessment, 26.6% of CCS were diagnosed with HF stage A, 21.1% with HF stage B and 2.1% with symptomatic HF, i.e. HF stage C/D. Importantly, prevalence of different HF stages varied strongly by specific tumor history. Compared to the population, the prevalence ratio (PR) was 1.16 [95% confidence interval 1.02/1.31] for stage A HF and 1.91 [1.63/2.23] for the composite of stage B to D HF in an age- and sex-adjusted Poisson regression model. Multivariable linear regression with the systolic marker left ventricular ejection fraction as dependent variable and adjustment for tumor entities, age, sex, and cardiovascular risk factors (CVRF) revealed a lower EF in patients with history of bone tumors (β −6.0 [−8.1/−3.0]), soft tissue sarcoma (β −2.2 [−4.1/−0.35]), leukemia (β −0.84 [−1.8/0.08]) and renal tumors (β −1.8 [−4.0/0.27]) compared to the population. In contrast, the same model for the diastolic marker E/E', showed an association only with CVRF, but not with tumor entities.

Conclusion

The prevalence of stage B to D HF was significantly higher among long-term CCS in the 3rd to 5th age decade compared to the population and varied strongly by tumor entity. Systolic dysfunction was primarily associated with history of tumor entities, whereas diastolic dysfunction was associated with the higher burden of CVRF in CCS.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): This study is funded by the Deutsche Forschungsgemeinschaft (DFG) (SP 1381/2-1&2, FA 1038/2-1&2, WI 3881/2-1&2)

Prevalence and outcome of cardiac amyloidosis in an all-comer population of patients with non-ischaemic heart failure

Background

Cardiac amyloidosis (CA) is increasingly recognized as an underlying cause of heart failure with preserved ejection fraction (HFpEF), associated with high morbidity and mortality. However, most studies, solely investigated the prevalence of CA in special subgroups including HFpEF and severe aortic valve disease.

Purpose

With the present study we sought to investigate prevalence of different phenotypes of CA in an all comer-population of patients with non-ischaemic heart failure (HF) and to analyze the impact of CA on all-cause mortality.

Methods

The My Biopsy HF-Study (German clinical trials register number: 22178) is a retrospective monocentric study investigating the underlying etiology of HF in an all-comer population of patients with HF of unknown etiology. Patients presenting with symptoms of HF at the University Medical Centre between 14/10/2012 and 01/03/2021, who underwent endomyocardial biopsy (EMB) were enrolled in the present study. Ischaemic HF and valvular HF were ruled out prior to EMB. Specimens were sent for further examination to a specialized laboratory approved by the Food and Drug Administration

Results

Between October 2012 and March 2021, 767 patients (71.6% men) with HF of unknown etiology were included. Mean age at the time of presentation was 55.4 years (±14.4). Altogether, 72.5% of the patients presented with HF with reduced ejection fraction (HFrEF), 7.1% were diagnosed with HF with mid-range ejection fraction (HFmrEF) and 20.4% with HFpEF. Based on histological examination and genotyping, CA was diagnosed in 44 (5.7%) patients (immunglobulin light chain [AL] CA: 15 patients; variant transthyretin [ATTRv] CA: 6 patients; wild type transthyretin [ATTRwt] CA: 21 patients; de novo CA: 2 patients). Patients with CA were older compared with patients without CA (69.4±11.4 vs. 54.1±14.5; p&lt;0.0001), had a higher prevalence of arterial hypertension (68.2% vs. 50.9%; p=0.045) and showed a better left ventricular ejection fraction based on echocardiographic examination (47.5% vs. 32.6%; p&lt;0.0001). With respect to biomarker expression, levels of both brain natriuretic peptide and high-sensitive troponin I were significantly higher in patients without CA (BNP: 914.1 vs 612; p=0.01; troponin I: 812.8 vs. 171.7; p=0.006). In univariate logistic regression analysis CA was associated with a significant all-cause mortality (hazard ratio [HR] per unit increase [ui], 5.17, 95% CI, 2.93–9.08; p&lt;0.0001), even after adjustment for classical cardiovascular risk factors (HRperui 3.12, 95% CI, 1.11–8.76; p=0.03) and comorbidities like chronic obstructive pulmonary disease, chronic kidney disease and stroke (HRperui 2.93, 95% CI, 1.2–7.15; p=0.018).

Conclusions

Among patients presenting with HF of unknown etiology, including patients with HFpEF, HFmrEF and HFrEF, cardiac amyloidosis is the underlying cause of HF in 5.7% of patients and is independently associated with all-cause mortality.

Funding Acknowledgement

Type of funding sources: None.

Impact of cardiac amyloidosis on outcomes of patients hospitalized with heart failure in Germany

Background

Amyloidosis is a multi-systemic disease resulting from deposition of misfolded proteins as insoluble fibrils in the interstitium of affected organs including the heart, subsequently leading to organ failure. Cardiac involvement is predominantly observed in light chain (AL) amyloidosis and wild-type transthyretin (ATTRwt) amyloidosis.

Purpose

We aimed to investigate prevalence and prognostic implications of cardiac amyloidosis of any etiology on outcomes of hospitalized patients with heart failure (HF) in Germany.

Methods

We analyzed data of the German nationwide inpatient sample (2005–2018) of patients hospitalized for HF (including myocarditis with HF and heart transplantation with HF). HF patients with amyloidosis (defined as cardiac amyloidosis [CA]) were compared with those HF patients without amyloidosis and impact of CA on outcomes was assessed (source: Research Data Center (RDC) of the Federal Statistical Office and the Statistical Offices of the federal states, DRG Statistics 2005–2018, and own calculations).

Results

During this fourteen-year observational period 5,478,835 hospitalizations of HF patients were analyzed. Amyloidosis was coded in 5,407 hospitalizations of HF patients (0.1%). Prevalence of CA was 1.87 hospitalizations per 100,000 German population. CA patients were younger (75.0 [IQR 67.0/80.0] vs. 79.0 [72.0–85.0] years, p&lt;0.001), predominantly male (68.9%) and had a higher prevalence of cancer (14.8% vs. 3.6%, P&lt;0.001) compared with HF without amyloidosis. Although patients without amyloidosis had a pronounced cardiovascular risk profile -especially arterial hypertension (45.4% vs. 35.6%; p&lt;0.001) and diabetes mellitus (38.9% vs. 18.5%; p&lt;0.001)- and a higher prevalence of concomitant coronary artery disease (40.5% vs. 34.5%; p&lt;0.001) and chronic obstructive pulmonary disease (17.1% vs. 9.4%; p&lt;0.001), adverse in-hospital events including necessity of transfusions of blood constituents (7.1% vs. 5.4%, p&lt;0.001) and cardio-pulmonary resuscitation (CPR, 2.7% vs. 1.4%; p&lt;0.001) were more frequent in CA. CA was independently associated with acute kidney failure (OR 1.40 [95% CI 1.28–1.52], p&lt;0.001), CPR (OR 1.58 [95% CI 1.34–1.86], p&lt;0.001), intracerebral bleeding (OR 3.13 [95% CI 1.68–5.83], p&lt;0.001) and in-hospital mortality in the 6th and 8th decade of life (6thdecade: OR 1.40 [95% CI 1.01–1.94], p=0.042; 8thdecade: OR 1.18 [95% CI 1.03–1.35], p=0.02).

Conclusions

CA was identified as an independent risk factor for complications and in-hospital mortality in HF patients. Physicians should be aware of this issue concerning treatments and monitoring of CA-patients.

Funding Acknowledgement

Type of funding sources: None.

Temporal trends, sex-differences and outcomes of patients hospitalized for heart failure in Germany

Background

Despite remarkable improvements in treatment of cardiovascular disease, heart failure (HF) is still characterized by a high mortality rate. Sex-specific differences in HF have been described, but underlying reasons are widely unexplored. Thus, we aimed to investigate sex differences of patients hospitalized for HF in a nationwide cohort.

Methods

The nationwide German inpatient sample (2005–2016) was used for this sex-specific analyses. Temporal trends on hospitalizations, mortality, and treatments were analyzed and independent predictors of adverse outcomes identified.

Results

The present analysis comprises 4,538,977 hospitalizations due to HF (52.0%women) in Germany (2005–2016). Although women were older (median 82 (IQR75–87) vs. 76 (69–82), P&lt;0.001), coronary artery disease (CAD, 50.3% vs. 30.7%, P&lt;0.001) was more prevalent in men, who were more often treated with PCI (3.4% vs. 1.4%, P&lt;0.001) and implantable cardioverter-defibrillator (2.2% vs. 0.5%, P&lt;0.001). In-hospital mortality was significantly lower in men than in women (8.9% vs. 10.2, P=0.001) and was reduced in patients who received PCI or implantation of an ICD.

While total numbers of hospitalizations between 2005 and 2016 increased in both men (β-estimate 7185.71 (95% CI 6502.23 to 7869.18), P&lt;0.001) and women (β-estimate 5297.60 (95% CI 4557.37 to 6037.83), P&lt;0.001) as well as almost all comorbid co-conditions, in-hospital mortality rate decreased more distinctly in women (β-estimate −0.41 (95% CI: −0.42 to −0.39), P&lt;0.001) compared to men (β-estimate −0.29 (95% CI: −0.30 to −0.27), P&lt;0.001).

Conclusions

Interventional treatments of HF were associated with improved outcomes and equally beneficial for both sexes. However, they were more often used in male HF patients, in which CAD is significantly more frequent than in female HF patients. This may explain the higher case fatality rate of HF in females.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): German Federal Ministry of Education and Research (BMBF)

Global longitudinal strain predicts outcome in chronic heart failure across American Heart Association stages: results from the MyoVasc study

Background

Global longitudinal strain (GLS) demonstrated a superior prognostic value over left ventricular ejection fraction (LVEF) in acute heart failure (HF). Its prognostic value across American Heart Association (AHA) stages of HF – especially under considering of conventional echocardiographic measures of systolic and diastolic function – has not yet been comprehensively evaluated.

Purpose

To evaluate the prognostic value of GLS for HF-specific outcome across AHA HF stages A to D.

Methods

Data from the MyoVasc-Study (n=3,289) were analysed. Comprehensive clinical phenotyping was performed during a five-hour investigation in a dedicated study centre. GLS was measured offline utilizing QLab 9.0.1 (PHILIPS, Germany) in participants presenting with sinus rhythm during echocardiography. Worsening of HF (comprising transition from asymptomatic to symptomatic HF, HF hospitalization, and cardiac death) was assessed during a structured follow-up with subsequent validation and adjudication of endpoints. AHA stages were defined according to current guidelines.

Results

Complete information on GLS was available in 2,400 participants of whom 2,186 categorized to AHA stage A to D were available for analysis. Overall, 434 individuals were classified as AHA stage A, 629 as stage B and 1,123 as stage C/D. Mean GLS increased across AHA stages of HF: it was lowest in stage A (−19.44±3.15%), −18.01±3.46% in stage B and highest in AHA stage C/D (−15.52±4.64%, P for trend &lt;0.0001). During a follow-up period of 3.0 [1.3/4.0] years, GLS denoted an increased risk for worsening of HF after adjustment for age and sex (hazard ratio, HRGLS [per standard deviation (SD)] 1.97 [95% confidence interval 1.73/2.23], P&lt;0.0001) in multivariable Cox regression analysis. After additional adjustment for cardiovascular risk factors, clinical profile, LVEF and E/E' ratio, GLS was the strongest echocardiographic predictor of worsening of HF (HRGLS [per SD] 1.47 [1.20/1.80], P=0.0002) in comparison to LVEF (HRLVEF [per SD] 1.23 [1.02/1.48], P=0.031) and E/E' ratio (HRE/E' [per SD] 1.12 [0.99/1.26], P=0.083). Interestingly, when stratifying for AHA stages, GLS denoted a similar increased risk for worsening of HF in individuals classified as AHA stage A/B (HRGLS [per SD] 1.63 [1.02/2.61], P=0.039) and in those classified as AHA stage C/D (HRGLS [per SD] 1.95 [1.65/2.29], P&lt;0.0001) after adjustment for age and sex. For further evaluation, Cox regression models with interaction analysis indicated no significant interaction for (i) AHA stage A/B vs C/D (P=0.83) and (ii) NYHA functional class &lt;II vs ≥II in individuals classified as AHA stage C/D (P=0.12).

Conclusions

GLS demonstrated a higher predictive value for worsening of HF than conventional echocardiographic measures of systolic and diastolic function. Interestingly, GLS indicated an increased risk for worsening of HF across AHA stages highlighting its potential value to advance risk prediction in chronic HF.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): German Center for Cardiovascular Research (DZHK), Center for Translational Vascular Biology (CTVB) of the University Medical Center of the Johannes Gutenberg-University Mainz

Sporadic Creutzfeldt-Jakob Disease among Physicians, Germany, 1993-2018

sCJD patients were significantly more likely than the general population to be physicians.

We investigated sporadic Creutzfeldt-Jakob disease (sCJD) among physicians in Germany by analyzing occupational information of patients with sCJD recorded by the German CJD Surveillance Unit (1993–2005; 1,250 patients, of whom 4 [0.32%] were physicians) and the National Reference Center for Human Spongiform Encephalopathies (2006–2016; 1,491 patients, of whom 13 [0.87%] were physicians). Among the physicians, we did not identify any neurologists, neurosurgeons, psychiatrists, or pathologists. A cumulative sum test showed an increase in reported physicians over time. Data for 2017–2018 indicated an increased rate of physicians among all notified sCJD cases (5/239 [2.1%]) when we used the total population of Germany as control group. Our data suggest the possibility of an increased risk for sCJD among physicians in Germany. However, we can only speculate about the reasons, and larger multinational studies are needed to replicate the finding and to clarify whether this finding is a general or a country-specific phenomenon.

OS3.2 Relevant topics for brain tumor patients in the Distress Thermometer, first results of the HEAT study

BACKGROUND

Patient-centered assessments and disease-adjusted patient-reported outcome measures (PROMs) are crucial in neuro-oncology. The Distress Thermometer (DT) is a well-accepted screening tool for cancer patients including a numerical rating scale (1–10, cut-offs indicating relevant distress ≥4–6) and 40 items describing possible problem categories (emotional, social, physical, practical and spiritual). The aims of the first part of the “Adaption of the Distress Thermometer in patients with intracranial tumors” (HEAT) study were to evaluate the importance and relevance of items for brain tumor patients (BTP).

MATERIAL AND METHODS

The multicenter study included three University hospitals. After given informed consent patients were prospectively evaluated either during their hospital stay or in the outpatient setting using DT as well as the 40 item problem list. Clinical and demographic data were recorded. We performed an analysis regarding frequency of indicated topics and evaluated their relevance for patients’ psychosocial well-beings via Pearson correlations with the DT score.

RESULTS

Data of n = 670 patients were analyzed. Mean age was 52 years (SD = 14, range 18–81), most of the patients harbored WHO°I tumors (37%) and WHO°IV tumors (28%). Male to female ratio was 1:1, 17% were assessed preoperatively, 40% postoperatively and 43% during adjuvant therapy or follow-up. 14% of the patients faced a tumor recurrence at assessment. Mean score of DT was 5.23 (SD = 2.9, range 0–10). Applying a cut-off score ≥ 4, 61% reported distress (≥ 5: 46% and ≥ 6: 37%). Regarding the relevance of the problem list for BTP, emotional problems (e. g., anxiety, depression) were most frequently reported. A total of 14/40 (35 %) of items were endorsed by less than 10% of patients. With exception of emotional problems all areas were reflected: practical problems (e. g., problems with child care or insurance), social problems (e. g., problems with children), spiritual concerns (e. g., loss of faith), and physical problems (e. g., breathing, fever). However, some of these rarely reported problems were of relevance for patients’ psychosocial well-being as indicated by significant correlations between the respective item and the DT score. This was, for example, the case for problems with childcare (r = .106; p < .01) or breathing (r = .125; p = .001).

CONCLUSION

Tools developed for cancer patients do not yet perfectly reflect all needs of BTP. Based on our data, we suggest further adjustments of available tools. Yet, it should be taken into account that subgroups of BTP may require different problem lists in the DT, as we observed some topics (e.g. breathing) probably be related to BTP under chemotherapy or steroids only. Moreover, our data require cross-cultural validation as especially results regarding practical problems and insurance might differ in cultures with different social security systems.

Plasma total prion protein as a potential biomarker for neurodegenerative dementia: diagnostic accuracy in the spectrum of prion diseases

AIMS

In the search for blood-based biomarkers of neurodegenerative diseases, we characterized the concentration of total prion protein (t-PrP) in the plasma of neurodegenerative dementias. We aimed to assess its accuracy in this differential diagnostic context.

METHODS

Plasma t-PrP was measured in 520 individuals including healthy controls (HC) and patients diagnosed with neurological disease control (ND), Alzheimer's disease (AD), sporadic Creutzfeldt-Jakob disease (sCJD), frontotemporal dementia (FTD), Lewy body dementia (LBD) and vascular dementia (VaD). Additionally, t-PrP was quantified in genetic prion diseases and iatrogenic CJD. The accuracy of t-PrP discriminating the diagnostic groups was evaluated and correlated with demographic, genetic and clinical data in prion diseases. Markers of blood-brain barrier impairment were investigated in sCJD brains.

RESULTS

Compared to HC and ND, elevated plasma t-PrP concentrations were detected in sCJD, followed by FTD, AD, VaD and LBD. In sCJD, t-PrP was associated neither with age nor sex, but with codon 129 PRNP genotype. Plasma t-PrP concentrations correlated with cerebrospinal fluid (CSF) markers of neuro-axonal damage, but not with CSF t-PrP. In genetic prion diseases, plasma t-PrP was elevated in all type of mutations investigated. In sCJD brain tissue, extravasation of immunoglobulin G and the presence of swollen astrocytic end-feet around the vessels suggested leakage of blood-brain barrier as a potential source of increased plasma t-PrP.

CONCLUSIONS

Plasma t-PrP is elevated in prion diseases regardless of aetiology. This pilot study opens the possibility to consider plasma t-PrP as a promising blood-based biomarker in the diagnostic of prion disease.

Plasma YKL-40 in the spectrum of neurodegenerative dementia

Background

Increased plasma YKL-40 has been reported in Alzheimer’s disease (AD), but its levels in other neurodegenerative diseases are unknown. Here, we aimed to investigate plasma YKL-40 in the spectrum of neurodegenerative dementias.

Methods

YKL-40 was quantified in the plasma of 315 cases, including healthy controls (HC), neurological disease controls (ND), AD, vascular dementia (VaD), frontotemporal dementia (FTD), sporadic Creutzfeldt-Jakob disease (CJD) and Lewy body dementia (LBD). Diagnostic accuracy in the differential diagnostic context and influence of age and gender was assessed.

Results

Highest YKL-40 levels were detected in CJD, followed by LBD, VaD, AD, FTD, ND and HC. YKL-40 was associated to age but not to sex. After controlling for age, YKL-40 was significantly elevated in CJD compared to HC (p < 0.001), ND, AD and VaD (p < 0.01) and in LBD compared to HC (p < 0.05). In CJD, YKL-40 concentrations were significantly higher at late disease stages.

Conclusions

Plasma YKL-40 is significantly elevated in CJD regardless of clinical and genetic parameters, with moderate diagnostic accuracy in the discrimination from control cases. Our study discards a potential use of this biomarker in the differential diagnostic context but opens the possibility to be explored as a marker for CJD monitoring.

Distinct microglia profile in Creutzfeldt-Jakob disease and Alzheimer's disease is independent of disease kinetics

Activated microglia represent a common pathological feature of neurodegenerative diseases. Sporadic Creutzfeldt-Jakob disease (sCJD) patients show more pronounced microglial activation than Alzheimer's disease (AD) patients. Whether these differences are due to differences in disease kinetics or represent disease-specific changes is unknown. We investigated microglial phenotypes in brains of rapidly progressive AD (rpAD) and sCJD patients matched for clinical presentation, including disease duration. We immunostained the frontal cortex, basal ganglia and cerebellum in 16 patients with rpAD and sCJD using antibodies against markers of microglia and recruited monocytes (ionized calcium-binding adaptor molecule 1, human leukocyte antigen DPQR, Cluster of Differentiation 68), an antibody unique to brain-resident microglia (transmembrane protein 119 (TMEM119)), in addition to antibodies against a marker of astrocytes (glial fibrillary acidic protein), amyloid-β (Aβ) and pathological prion protein. rpAD patients showed a distinct microglial phenotype with a high abundance of TMEM119-positive microglia in all investigated regions. Presence of Aβ deposits seen in a sCJD patient with concomitant deposition of Aβ led to increase of TMEM119-positive microglia. Our data suggest that in rpAD, activation of brain-resident microglia significantly contributes to microgliosis, whereas in sCJD the TMEM119 signature of resident microglial cells is barely detectable. This is irrespective of disease duration and may indicate disease-specific microglial reaction.

Validation and utilization of amended diagnostic criteria in Creutzfeldt-Jakob disease surveillance

Objective

To validate an amended protocol for clinical diagnosis of sporadic Creutzfeldt-Jakob disease (sCJD) including real-time quaking-induced conversion (RT-QuIC) and to observe its use in CJD surveillance.

Methods

In the framework of a prospective epidemiologic study, all neuropathologically confirmed cases with sCJD who received CSF RT-QuIC analysis during diagnostic workup (n = 65) and a control group of individuals without CJD (n = 118) were selected to investigate the accuracy of an amended diagnostic protocol. The patients had been referred to the German National Reference Center for Transmissible Spongiform Encephalopathies. The influence of the amended protocol on incidence figures was evaluated in the context of 3 years of surveillance activity (screened cases using 14-3-3 test n = 18,789, highly suspicious cases of CJD n = 704). Annual incidences were calculated with current criteria and the amended protocol.

Results

The amended protocol showed a sensitivity of 97% and a specificity of 99%. When it was applied to all suspected cases who were referred to the reference center, the assessed incidence of CJD increased from 1.7 to 2.2 per million in 2016.

Conclusion

CJD surveillance remains challenging because information from external health care institutions can be limited. RT-QuIC shows excellent diagnostic accuracy when applied in the clinical setting to symptomatic patients. Data for RT-QuIC alone when applied as a general screening test are not available yet. We propose an amended research protocol that improves early and accurate clinical diagnosis of sCJD during surveillance activities. The use of this protocol will probably lead to a significant increase of the incidence rate.

Classification of evidence

This study provides Class III evidence that for patients with suspected sCJD, criteria for clinical diagnosis plus the CSF RT-QuIC accurately identifies patients with sCJD (sensitivity 97%, specificity 99%).

CSF nonphosphorylated Tau as a biomarker for the discrimination of AD from CJD

Creutzfeldt–Jakob disease and Alzheimer's disease are characterized by the presence of elevated total‐Tau cerebrospinal fluid concentrations while the presence of hyperphosphorylated Tau forms in the cerebrospinal fluid is rather a hallmark of Alzheimer's disease. Here we aimed to investigate potential contribution of nonphospho‐Tau epitopes (non‐P‐Tau) in the discrimination between both diseases. Non‐P‐Tau cerebrospinal fluid concentration was highly increased in Creutzfeldt–Jakob disease (n = 57, 3683 ± 3599 pg/mL) compared to Alzheimer's disease (n = 41, 148 ± 219 pg/mL) and neurological controls (n = 56, 62 ± 40 pg/mL), and significantly improved the proportion of correctly classified patients (99%) compared to that achieved by total‐Tau (90%), P‐Tau (62%) and 14‐3‐3 (91%).

Cerebrospinal fluid neurofilament light levels in neurodegenerative dementia: Evaluation of diagnostic accuracy in the differential diagnosis of prion diseases

INTRODUCTION

Neurofilament light (NFL) levels in the cerebrospinal fluid are increased in several neurodegenerative dementias. However, their diagnostic accuracy in the differential diagnostic context is unknown.

METHODS

Cerebrospinal fluid NFL levels were quantified in nonprimarily neurodegenerative neurological and psychiatric diseases (n = 122), mild cognitive impairment (n = 48), Alzheimer's disease (n = 108), dementia with Lewy bodies/Parkinson's disease dementia (n = 53), vascular dementia (n = 46), frontotemporal dementia (n = 41), sporadic Creutzfeldt-Jakob disease (sCJD, n = 132), and genetic prion diseases (n = 182).

RESULTS

The highest NFL levels were detected in sCJD, followed by vascular dementia, frontotemporal dementia, dementia with Lewy bodies/Parkinson's disease dementia, Alzheimer's disease, and mild cognitive impairment. In sCJD, NFL levels correlated with cerebrospinal fluid tau and disease duration. NFL levels were able to differentiate sCJD from nonprimarily neurodegenerative neurological and psychiatric diseases (area under the curve = 0.99, 95% confidence interval: 0.99-1) and from the other diagnostic groups showing cognitive impairment/dementia of a non-CJD etiology (area under the curve = 0.90, 95% confidence interval: 0.87-0.92). Compared to nonprimarily neurodegenerative neurological and psychiatric diseases, NFL was also elevated in genetic prion diseases associated with the E200K, V210I, P102L, and D178N prion protein gene mutations.

DISCUSSION

Increased NFL levels are a common feature in neurodegenerative dementias.

Adapting smartphone-based photoplethysmograpy to suboptimal scenarios

Photoplethysmography (PPG) is an optical technique used to measure the heart rate (HR) and other cardiovascular variables by analyzing volume changes in the microvascular bed of tissue. At the moment, smartphone users can already measure their HR using PPG applications that use the smartphone's built-in camera. However, available applications are unreliable when artifacts are present, such as those caused by movement, finger pressure, or ambient light changes. This contribution aims to analyze the limitations of a smartphone-based PPG algorithm capable of measuring N-N intervals when such artifacts are present by comparing it to a 2-lead electrocardiography (ECG). By using a Bandpass filter and a zero-crossing detection algorithm on a PPG signal captured at 800  ×  600 pixels and 30 Hz, we have designed an approach capable of assessing N-N intervals when movement artifacts are present. An evaluation performed on n  =  31 users shows our algorithm is capable of measuring N-N intervals with an average relative error of 9.23 ms, when compared to a 2-lead ECG. Our approach proves the reliability of smartphone-based photoplethysmography to measure N-N intervals, even under the presence of movement artifacts, and opens the door for its future use in remote diagnosis scenarios.

[Minimally invasive retrograde drilling of osteochondral lesions of the femur using an arthroscopic drill guide]

OBJECTIVE

Retrograde drilling for penetration of subchondral sclerotic bone in osteochondrosis dissecans (OCD) of the femoral condyle with preserved cartilage integrity. Hereby, revascularization of the OCD and immigration of bone marrow cells to achieve stable reintegration of the OCD into the surrounding subchondral bone.

INDICATIONS

Stable juvenile and adult osteochondrosis dissecans (stage I-II of the International Cartilage Repair Society (ICRS) classification) of the medial and lateral femoral condyle with an intact articular surface and surrounding sclerosis zone, which is visible in the x-ray.

CONTRAINDICATIONS

OCD stage III-IV of the ICRS grading scale. Relative contraindication: preceding retrograde drilling.

SURGICAL TECHNIQUE

Arthroscopic inspection and palpation of the cartilage defect. Minimal incision over the M. vastus medialis (when the defect is located in the medial condyle) or the M. vastus lateralis (when the defect is located in the medial condyle). Preparation and dissection of the fascia of the vastus muscle. Insertion of retractors underneath the vastus muscle to expose the metaphysis of the distal femur. Intraarticular positioning of the arthroscopic drill guide, placement of the wire guide and a Kirschner(K) wire on the femur metaphysis and retrograde drilling with a 2.0-2.2 mm K wire under radiographic visualization. Length measurement of the intraosseous wire distance. Switch the guide mechanism to a multiple hole drill guide and, depending on the defect size, insertion of a further 7-10 K wires of same thickness and defined length.

POSTOPERATIVE MANAGEMENT

Sterile bandage and slightly compressive dressing. Continuous active and passive knee motion. Weight bearing of 20 kg for 6 weeks, with subsequent transition to continuous weight bearing. Radiographic controls at 6 and 12 weeks postoperatively. In case of a persistent sclerosis zone in the control x-ray or clinical abnormalities, control MRI is indicated.

RESULTS

A total of 55 patients with a mean age of 19.6 years were treated using the described technique: 49 patients (89.1%), and 54 knees respectively (35 juvenile OCD, 19 adult OCD), were seen with a mean follow-up of 37.9 months. An improvement was observed in 81.6% of the knees using the radiographic score, i.e., a mean improvement of 1.13 of the radiographic score published by Rodegerdts and Gleissner (preoperative 3.04 vs. postoperative 1.91). Juvenile OCD showed better radiographic results overall (88.2% healing) than adult OCD (66.7% healing).

Distress in patients with newly diagnosed brain tumours

OBJECTIVE

Patients with intracranial tumours often suffer from clinically relevant psychological distress. However, levels of distress and contributing factors have not been systematically evaluated for the early course of the disease. Using the National Comprehensive Cancer Network's Distress Thermometer (DT), we evaluated the extent and sources of distress within a population of patients with intracranial neoplasms.

METHODS

One hundred and fifty-nine patients were included who underwent craniotomy for newly diagnosed intracranial tumours at our department. All patients completed the DT questionnaire, a single-item 11-point visual analogue scale measuring psychological distress. The appendant problem list (PL) consists of 40 items representing problems commonly experienced by cancer patients. Patients were asked to mark any experienced sources of distress.

RESULTS

Percentage of patients suffering from relevant distress was 48.4% (cut-off ≥6). DT-scores were significantly associated with depression and anxiety as well as reported number of concerns. On average, patients reported 6.9 sources of cancer-related distress. Objective medical data (e.g. tumour stage) as well as sociodemographic data (e.g. gender, IQ) were not associated with psychological distress at this early phase.

CONCLUSIONS

Prevalence of elevated distress is high shortly after primary neurosurgical treatment in patients with intracranial tumours and cannot be predicted by objective data. As a consequence, sources of distress can and should be routinely assessed and targeted in these individuals in this particular period. Further studies are needed to help to identify patients who are at risk of suffering from long-term emotional distress in order to enable targeted psychosocial intervention.

[Perioperative pain therapy in interventions for elbow stiffness]

Conservative treatment and surgical release of a stiff elbow requires correct pain management which should be oriented to the individual needs of the patient. Regional anesthesia in combination with opioids is necessary postoperatively to obtain sufficient pain relief. There is a need for prospective randomized studies to develop an optimal pain therapy concept following operations for elbow stiffness.

[Elevated postoperative pain levels following orthopedic surgery. Depression as a strong predictor]

The aim of this study was to examine whether depression is a strong predictor of elevated postoperative pain levels following orthopedic surgery and whether the implementation of standardized pain management is more beneficial for patients with depression. We performed a non-randomized, prospective study with two different groups of patients who underwent orthopedic surgery. Group 1 (n=249) received non-standardized pain therapy whereas group 2 (n = 243) was treated with a standardized pain management concept. Effects of the treatment were monitored with a VAS-based pain assessment protocol. Depression was measured preoperatively with the self-reported Patient Health Questionnaire (PHQ-9). Patients with the probable diagnosis of a current episode of major depression showed significantly higher postoperative pain than patients without a depressive episode. On the other hand, patients with depression benefited from the implementation of standardized pain management. Our data suggest a predictive value of depression for severe postoperative pain. Patients with depression benefited from standardized postoperative pain therapy, but were still suffering from significantly higher postoperative pain.

[Implementation of standardized postoperative pain therapy for orthopaedic patients. Comparison between unsystematic and standardized pain therapy]

BACKGROUND

The painless clinic and postoperative pain therapy are currently major issues in the management of surgical procedures. The aim of this study was to evaluate the benefit of a standardized pain therapy on the postoperative pain level after orthopaedic procedures.

PATIENTS AND METHODS

We investigated two different groups of patients who underwent an orthopaedic surgical procedure. Group 1 (n = 249) received a pain therapy which was based on an individual and surgery-dependent concept whereas group 2 (n = 243) was treated with a standardized pain therapy concept. The effect of the treatment was monitored with a VAS-based protocol.

RESULTS

Up to day 9 after surgery there was a significant difference between the two groups in regard to the postoperative pain. The patients of group 2 had less pain but had more unwanted side effects caused by the pain therapy during the first 3 days after surgery. Mobility and mental disposition were positively affected.

CONCLUSION

The implementation of a standardized pain therapy is successful in reducing postoperative pain. Mobility and mental disposition are also influenced positively. As a consequence the incidence of unwanted side effects is rising.

Investigations of the potential risk factors associated with cases of bovine spongiform encephalopathy in Bavaria, Germany

In order to identify the management and feeding practices that might have contributed to the occurrence of bovine spongiform encephalopathy (BSE) in Bavaria, Germany, information from 110 dairy farms on which a case of BSE had been reported was compared with information derived from a questionnaire sent to approximately 10,000 Bavarian farms on which no case of BSE had been reported up to February 2003. Representative information was obtained from 4006 dairy farms. The results indicated that in comparison with these control farms a higher proportion of the BSE farms had also kept pigs or poultry, although the difference was not significant, and that a significantly higher proportion of the BSE farms had fed proprietary concentrates and/or milk replacers to their calves.

Impact of stage differentiation on diagnosis of toxoplasmosis

Within its intermediate host, such as man, the protozoan parasite Toxoplasma gondii interconverts between tachyzoites and bradyzoites. The replicative tachyzoite stage is thought to be responsible for acute/active infection and expresses immunodominant antigens thereby inducing a strong cellular immune response, which vice versa triggers the differentiation process into dormant and immunologically weak cyst stages. The immunodominance of tachyzoites is also responsible for the induction of a strong humoral immune response leading to the formation of antibodies specifically directed against tachyzoite antigens. In contrast, the bradyzoite stage which is associated with inactive/chronic infection, seems not to be a strong inducer of specific antibodies. However, since the humoral antibody response is also directed against antigens that are expressed in both stages, serodiagnosis cannot always adequately discriminate between active and inactive/chronic infection. This short review focuses on the impact of stage differentiation and discusses the potential of stage-specifically expressed antigens that might be useful in a recombinant form in order to improve future serodiagnostical approaches.

In situ Analysis of Coronary Terminal Arteriole Diameter Responses: Technical Report of a New Experimental Model

INTRODUCTION

To date, investigation of coronary arteriole vasomotor activity has been limited to arterioles >30- 40 microm. Here, we introduce a new experimental model to allow for in situ microscopy of terminal coronary arterioles.

METHODS

Rat hearts were perfused in a closed loop system (priming volume 20 ml) which was placed on a computer-controlled microscope stage. FITC-dextran and tetrodotoxin (TTX, 50 microM) were added. Tilting of the microscope by 90 degrees allowed for visual access to the ventricular surface. Arterioles were identified by the flow direction of fluorescent beads (1 microm). Images were recorded on video tape, and arteriole diameters were measured offline. Stability of the preparation and maintenance of coronary flow reserve were analyzed. Responses of coronary flow and arteriole diameters to the vasodilators papaverine and Na-nitroprusside were recorded.

RESULTS

In TTX-arrested control hearts coronary flow and terminal arteriole diameters were stable for 2 h. Administration of papaverine and Na-nitroprusside increased coronary flow from 6.4 +/- 0.7 to 13.3 +/- 1.3 ml/min, decreasing coronary resistance by 52 +/- 3%. Terminal coronary arteriole diameters increased from 12.0 +/- 0.9 to 13.6 +/- 1.0 microm, decreasing hindrance of this vessel segment by 45 +/- 11%.

CONCLUSION

Preservation of coronary terminal arteriolar tone and adequate responsiveness to vasodilators in the TTX-arrested isolated heart were demonstrated. Thus, this model may serve to complement our understanding of coronary microvascular control mechanisms by extending observations to the terminal arteriolar bed.

Relapse in the skull after myeloablative therapy for high-risk neuroblastoma

Patterns of relapse were determined for 20 high-risk neuroblastoma patients treated with chemotherapy, surgery, primary and metastatic site radiation (21 Gray), myeloablative chemotherapy, peripheral blood stem cell rescue, and 13-cis-retinoic acid. The median follow-up duration after transplant is 21 months (range, 8-34 months). The event-free survival and overall survival at 2 years were 45 and 75%, respectively. There were 2 primary site recurrences. Metastatic sites that became MIBG-scan negative on induction chemotherapy were not irradiated. Four patients relapsed in irradiated metastatic sites, 3 in the skull, 1 in the liver. Failure also occurred at 2 skull sites treated with chemotherapy only, and at 5 new sites: 1 skull, 2 distant lymph nodes, and 2 bones other than skull. Eight of 20 patients had skull metastasis at presentation; 6 were irradiated and 3 were controlled. Skull metastasis warrants more aggressive evaluation and treatment.

Inhibition of host cell apoptosis by Toxoplasma gondii is accompanied by reduced activation of the caspase cascade and alterations of poly(ADP-ribose) polymerase expression

The obligate intracellular protozoan parasite Toxoplasma gondii has been shown to protect different cell types from apoptosis induced by a variety of pro-apoptotic treatments. However, the precise cell biological mechanisms of this inhibition remained unknown. As shown in this study, apoptosis in human-derived HL-60 and U937 cells induced by treatment with actinomycin D or TNF-α in combination with cycloheximide, respectively, was indeed dose-dependently downregulated by prior infection with T. gondii, as determined by DNA fragmentation assays. Cleavage of caspase 3 and caspase 9 after treatment with pro-apoptotic stimuli was considerably diminished by T. gondii. Furthermore, release of mitochondrial cytochrome c during apoptosis in HL-60 cells was prevented by intracellular parasites and this was correlated with the absence of DNA strand breaks on the single cell level. Inhibition of cytochrome c release coincided with a twofold upregulation of Mcl-1 protein levels in HL-60 and U937 cells, while Bcl-2 expression did not increase after infection. Parasitic interference with the caspase cascade led to a reduced proteolytic cleavage of the nuclear target molecule protein kinase Cδ. In parallel, poly(ADP-ribose) polymerase protein levels were prominently downregulated by T. gondii, irrespective of whether HL-60 and U937 cells had been treated with pro-apototic stimuli or left untreated. However, poly(ADP-ribose) polymerase mRNA levels remained unchanged after infection as determined by RT-PCR analyses. These observations suggest that T. gondii has evolved different mechanisms that may contribute to downregulation of host cell apoptosis, namely inhibition of cytochrome c release and subsequent caspase activation as well as downregulation of poly(ADP-ribose) polymerase protein levels.

Are some memory deficits unique to lesions of the mammillary bodies?

The role of the mammillary bodies in human memory is still in debate. A recent model of human amnesia proposes similar functions for the mammillary bodies and the hippocampus. But the main evidence for this model comes from animal studies using the delayed non-matching to sample paradigm. We describe a patient who developed a severe memory impairment after surgical removal of a germinoma. Postsurgical high resolution MRI revealed bilaterally shrunken mammillary bodies and an infarct of the left mammillary body. There were no other relevant lesions. Neuropsychological testing showed mildly impaired frontal lobe functions (executive functions, working memory and word fluency), almost intact learning and recognition, but severely impaired free and delayed recall. Experimental investigations revealed a reduced but preserved release of proactive interference and a pronounced impairment of recency and source judgments. We conclude that the mammillary bodies do play a prominent role in human memory, although the role differs slightly from that of the hippocampus.

Invasion by Toxoplasma gondii protects human-derived HL-60 cells from actinomycin D-induced apoptosis

Intracellular microorganisms have to rely on the integrity of their host cells to persist. We, therefore, investigated the effect of infections with different Toxoplasma gondii strains on apoptosis of human-derived HL-60 cells at the single cell level. Infection with either mouse-avirulent (NTE strain) or virulent parasites (RH strain) did not induce apoptosis of HL-60 cells as compared to uninfected controls. In contrast, treatment with actinomycin D (act D) led to apoptosis in 15-25% of the cells. However, concomitant infection with T. gondii clearly abrogated act D-induced apoptosis. This was especially apparent in those host cells that were actually infected; in these parasite-positive cells the rate of apoptosis decreased by 82.8+/-4.3% (mean+/-SEM, P=0.017, Student's t-test) and 91.7+/-3.4% (P= 0.024) after infection with either the NTE or the RH strain, respectively. Inhibition of host cell apoptosis was similarly observed in cells which had been invaded by UV-irradiated, non-replicating parasites (P=0.001, Student's t-test). However, incubation with heat-killed parasites or T. gondii lysates did not abrogate act D-induced apoptosis. In conclusion, inhibition of apoptosis by living, but not necessarily replicating T. gondii may facilitate parasite survival and persistence within its host cell.