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"Piper, K"
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Mental health in myasthenia gravis patients and its impact on caregiver burden
2022
Psychiatric comorbidities are relevant in patients with Myasthenia gravis (MG). Also, MG patients experience a reduced health-related quality of life (HRQoL). We aimed to quantify the impact of depression as well as self-perceived MG severity on HRQoL and caregivers' burden. In this cross-sectional study, we used a survey encompassing demographic, disease-related information, and standardized questionnaires to assess symptoms of depression, anxiety, HRQoL (MG Quality of Life scale; MG-QoL15), and caregiver burden (Burden Scale for Family Caregivers; BSFC). Data from 1399 participating patients (96%) and 1042 caregivers (65%) were eligible for further analysis. Symptoms of depression and anxiety disorder were indicated by 31% and 36% of patients. Self-reported MG severity (MG severity) and MG-QoL15 scores were strongly associated (estimated marginal means for severe versus mild MG severity = 18 95% CI [16; 21];
p
≤ 0.001). Adjusting for symptoms of depression decreased the estimated strength of this association (estimated marginal means for severe versus mild MG severity = 15 [13; 17];
p
≤ 0.001). Caregiver burden was associated to MG disease severity (estimated marginal means for severe vs. mild MG severity = 0.16 [0.13; 0,19);
p
≤ 0.001) and also negatively influenced by symptoms of depression (estimated marginal means = 0.12 [0.09; 0.15]). Symptoms of depression and anxiety disorder in MG are frequent. Beyond MG severity, symptoms of depression have negative effects on HRQoL as well as on caregivers’ burden. Diagnosis and treatment of psychiatric comorbidities should be considered an important element in MG care. Screening tools for mental health conditions should be implemented at least in specialized MG centers.
Journal Article
Where Have All the Rodents Gone? The Effects of Attrition in Experimental Research on Cancer and Stroke
by
Dirnagl, Ulrich
,
Diamantaras, Andreas Antonios
,
Holman, Constance
in
Animal Experimentation
,
Animals
,
Bias
2016
Given small sample sizes, loss of animals in preclinical experiments can dramatically alter results. However, effects of attrition on distortion of results are unknown. We used a simulation study to analyze the effects of random and biased attrition. As expected, random loss of samples decreased statistical power, but biased removal, including that of outliers, dramatically increased probability of false positive results. Next, we performed a meta-analysis of animal reporting and attrition in stroke and cancer. Most papers did not adequately report attrition, and extrapolating from the results of the simulation data, we suggest that their effect sizes were likely overestimated.
Journal Article
Thromboembolic complications in critically ill COVID-19 patients are associated with impaired fibrinolysis
by
Kruse, Jan Matthias
,
Zickler, Daniel
,
Dörner, Thomas
in
Antigens
,
Blood
,
Blood clotting disorders
2020
Background
There is emerging evidence for enhanced blood coagulation in coronavirus 2019 (COVID-19) patients, with thromboembolic complications contributing to morbidity and mortality. The mechanisms underlying this prothrombotic state remain enigmatic. Further data to guide anticoagulation strategies are urgently required.
Methods
We used viscoelastic rotational thromboelastometry (ROTEM) in a single-center cohort of 40 critically ill COVID-19 patients.
Results
Clear signs of a hypercoagulable state due to severe hypofibrinolysis were found. Maximum lysis, especially following stimulation of the extrinsic coagulation system, was inversely associated with an enhanced risk of thromboembolic complications. Combining values for maximum lysis with D-dimer concentrations revealed high sensitivity and specificity of thromboembolic risk prediction.
Conclusions
The study identifies a reduction in fibrinolysis as an important mechanism in COVID-19-associated coagulopathy. The combination of ROTEM and D-dimer concentrations may prove valuable in identifying patients requiring higher intensity anticoagulation.
Journal Article
Isolation, establishment, and characterization of immortalized ileum bovine intestinal epithelial cell line
2025
Primary intestinal epithelial cells are a powerful tool to study tight junction protein function and barrier integrity of epithelial cells. However, primary cells are costly, difficult to isolate, have a finite ability to replicate, and require the usage of live tissue. An alternative to primary cells is immortalized cell lines, which are cost effective, easily cultured, stored, and maintain the physiology of primary cells. Several immortalized lines are commercially available, yet there remains a need for cell lines for livestock research, specifically bovine. Here we report an immortalized bovine intestinal epithelial cell (IBEC) line was established by transfection with exogenous human telomerase reverse transcriptase (
hTERT
). Primary bovine intestinal epithelial cells (PBECs) were isolated from a 2-day old mixed breed calf. PBECs were transfected with
hTERT
to create an IBEC line. The transfected cells were positive for intestinal epithelial markers while testing negative for fibroblast markers. There was no significant difference in IBEC morphology or physiology post immortalization. In Trans-Epithelial Electrical Resistance (TEER assays), PBECs and IBECs behaved similarly to intestinal porcine enterocyte cells (IPEC-J2) under treatment of Iipopolysaccharide and calcium butyrate. This newly-developed cell line will be an essential and useful tool for in vitro bovine and ruminant intestinal research.
Journal Article
Role of ghrelin isoforms in the mitigation of hepatic inflammation, mitochondrial dysfunction, and endoplasmic reticulum stress after bariatric surgery in rats
2020
Background/objectivesBariatric surgery improves nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH), but the underlying mechanisms remain elusive. We evaluated the potential role of ghrelin isoforms in the amelioration of hepatic inflammation after sleeve gastrectomy and Roux-en-Y gastric bypass (RYGB).Subjects/methodsPlasma ghrelin isoforms were measured in male Wistar rats (n = 129) subjected to surgical (sham operation, sleeve gastrectomy, or RYGB) or dietary interventions [fed ad libitum a normal (ND) or a high-fat diet (HFD) or pair-fed diet]. The effect of acylated and desacyl ghrelin on markers of inflammation, mitochondrial dysfunction, and endoplasmic reticulum (ER) stress in primary rat hepatocytes under palmitate-induced lipotoxic conditions was assessed.ResultsPlasma desacyl ghrelin was decreased after sleeve gastrectomy and RYGB, whereas the acylated/desacyl ghrelin ratio was augmented. Both surgeries diminished obesity-associated hepatic steatosis, CD68+- and apoptotic cells, proinflammatory JNK activation, and Crp, Tnf, and Il6 transcripts. Moreover, a postsurgical amelioration in the mitochondrial DNA content, oxidative phosphorylation (OXPHOS) complexes I and II, and ER stress markers was observed. Specifically, following bariatric surgery GRP78, spliced XBP-1, ATF4, and CHOP levels were reduced, as were phosphorylated eIF2α. Interestingly, acylated and desacyl ghrelin inhibited steatosis and inflammation of palmitate-treated hepatocytes in parallel to an upregulation of OXPHOS complexes II, III, and V, and a downregulation of ER stress transducers IRE1α, PERK, ATF6, their downstream effectors, ATF4 and CHOP, as well as chaperone GRP78.ConclusionsOur data suggest that the increased relative acylated ghrelin levels after bariatric surgery might contribute to mitigate obesity-associated hepatic inflammation, mitochondrial dysfunction, and ER stress.
Journal Article
Development of intersectoral medical care for patients with ‘chronic critical illness’: protocol for a telemedicine interventional study with a pre-post design in out-of-hospital intensive care facilities (E=MC²)
by
Berger, Elke
,
Weiss, Bjoern
,
Spies, Claudia
in
Anxiety
,
Chronic Disease - therapy
,
Chronic illnesses
2025
IntroductionPatients receiving long-term ventilation (LTV) in out-of-hospital intensive care facilities often suffer from persistent impairments of their cognition, mental health and physical health, limiting their social participation. Chronically ill patients are often unable to express their care preferences. Thus, their medical care often lacks integration of patients’ wishes and values. Telemedicine may be used to collect patient-reported outcome measures (PROMs) from these patients to align medical care with their preferences. Early integration of teleconsultation to provide rapid support for specific patient symptoms can reduce economic costs.Method and analysisThis is a multicentre, prospective, non-blinded, single-arm interventional trial with a pre-post design and follows the Standard Protocol Items: Recommendations for Interventional Trials statement. 10 out-of-hospital intensive care facilities in Berlin and Brandenburg, Germany, are grouped into three clusters. The study population includes adult patients (≥18 years) receiving LTV and residing in participating care facilities. During the preintervention phase, standard patient care remains unchanged. From the start of the intervention phase, enrolled patients receive telemedicine rounds in addition to standard care. These telemedicine rounds, conducted at least weekly, involve on-site healthcare professionals, patients and their relatives. Data are collected at predefined time points—study months 1,3, 9, 15 and 21—with a target of 57 participants at each time point. The study aims to evaluate whether a structured telemedicine intervention (1) increases the proportion of patients receiving record-documented PROMs in routine care and (2) reduces hospital readmissions. Secondary outcomes include the evaluation of post-intensive care syndrome, healthcare costs and the usability, applicability and perceived benefits of telemedicine. Additionally, qualitative interviews with patients, their relatives and healthcare professionals will explore individual experiences with chronic critical illness, the perceived quality of life of the patients and how team members manage moral distress in caregiving contexts. A mixed-effects logistic regression model will be used to analyse patients’ access to PROMs, while a mixed-effects Poisson regression model will be employed to evaluate hospital readmission rates. The findings may provide valuable insights into how telemedicine can improve patient-centred care for this particular patient group.Ethics and disseminationThis study protocol received approval from the Ethics Committee of Charité—Universitätsmedizin Berlin, Germany (EA2/136/22). The findings will be disseminated through publication in a peer-reviewed scientific journal and presented at international conferences.Trial registration numberThis study was registered in the ‘German Register of Clinical Studies’ (DRKS; DRKS00029326).
Journal Article
The ratio between cerebral blood flow and Tmax predicts the quality of collaterals in acute ischemic stroke
by
Khalil, Ahmed
,
Kochova, Elena
,
Fiebach, Jochen B.
in
Angiography
,
Biology and Life Sciences
,
Biometrics
2018
In acute ischemic stroke the status of collateral circulation is a critical factor in determining outcome. We propose a less invasive alternative to digital subtraction angiography for evaluating collaterals based on dynamic-susceptibility contrast magnetic resonance imaging.
Perfusion maps of Tmax and cerebral blood flow (CBF) were created for 35 patients with baseline occlusion of a major cerebral artery. Volumes of hypoperfusion were defined as having a Tmax delay of > 4 seconds (Tmax4s) and > 6 seconds (Tmax6s) and a CBF drop below 80% of healthy, contralateral tissue. For each patient a ratio between the volume of the CBF and the Tmax based perfusion deficit was calculated. Associations with collateral status and radiological outcome were assessed with the Mann-Whitney-U test, uni- and multivariable logistic regression analyses as well as area under the receiver-operator-characteristic (ROC) curve.
The CBF/Tmax volume ratios were significantly associated with bad collateral status in crude logistic regression analysis as well as with adjustment for NIHSS at admission and baseline infarct volume (OR = 2.5 95% CI[1.2-5.4] p = 0.020 for CBF/Tmax 4s volume ratio and OR = 1.6 95% CI[1.0-2.6] p = 0.031 for CBF/Tmax6s volume ratio). Moreover, the ratios were significantly correlated to final infarct size (Spearman's rho = 0.711 and 0.619, respectively for the CBF/Tmax4s volume ratio and CBF/Tmax6s volume ration, all p<0.001). The ratios also had a high area under the ROC curve of 0.93 95%CI[0.86-1.00]) and 0.90 95%CI[0.80-1.00]respectively for predicting poor radiological outcome.
In the setting of acute ischemic stroke the CBF/Tmax volume ratio can be used to differentiate between good and insufficient collateral circulation without the need for invasive procedures like conventional angiography.
Journal Article
Tumour-infiltrating lymphocytes predict for outcome in HPV-positive oropharyngeal cancer
2014
Background:
Human papillomavirus (HPV)-positive oropharyngeal cancer (OPSCC) is associated with improved survival compared with HPV-negative disease. However, a minority of HPV-positive patients have poor prognosis. Currently, there is no generally accepted strategy for identifying these patients.
Methods:
We retrospectively analysed 270 consecutively treated OPSCC patients from three centres for effects of clinical, pathological, immunological, and molecular features on disease mortality. We used Cox regression to examine associations between factors and OPSCC death, and developed a prognostic model for 3-year mortality using logistic regression analysis.
Results:
Patients with HPV-positive tumours showed improved survival (hazard ratio (HR), 0.33 (0.21–0.53)). High levels of tumour-infiltrating lymphocytes (TILs) stratified HPV-positive patients into high-risk and low-risk groups (3-year survival; HPV-positive/TIL
high
=96%, HPV-positive/TIL
low
=59%). Survival of HPV-positive/TIL
low
patients did not differ from HPV-negative patients (HR, 1.01;
P
=0.98). We developed a prognostic model for HPV-positive tumours using a ‘training’ cohort from one centre; the combination of TIL levels, heavy smoking, and T-stage were significant (AUROC=0·87). This model was validated on patients from the other centres (detection rate 67%; false-positive rate 5.6%; AUROC=0·82).
Interpretation:
Our data suggest that an immune response, reflected by TIL levels in the primary tumour, has an important role in the improved survival seen in most HPV-positive patients, and is relevant for the clinical evaluation of HPV-positive OPSCC.
Journal Article
Biomarkers of immune capacity, infection and inflammation are associated with poor outcome and mortality after stroke - the PREDICT study
by
Mengel, A.
,
Hoffmann, S.
,
Grittner, U.
in
Atrial fibrillation
,
Biological markers
,
Biomarkers
2019
Background
Almost 40% of stroke patients have a poor outcome at 3 months after the index event. Predictors for stroke outcome in the early acute phase may help to tailor stroke treatment. Infection and inflammation are considered to influence stroke outcome.
Methods
In a prospective multicenter study in Germany and Spain, including 486 patients with acute ischemic stroke, we used multivariable regression analysis to investigate the association of poor outcome with monocytic HLA-DR (mHLA-DR) expression, interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor alpha (TNF-alpha) and lipopolysaccharide-binding protein (LBP) as markers for immunodepression, inflammation and infection. Outcome was assessed at 3 months after stroke via a structured telephone interview using the modified Rankin Scale (mRS). Poor outcome was defined as a mRS score of 3 or higher which included death. Furthermore, a time-to-event analysis for death within 3 months was performed.
Results
Three-month outcome data was available for 391 patients. Female sex, older age, diabetes mellitus, atrial fibrillation, stroke-associated pneumonia (SAP) and higher National Institute of Health Stroke Scale (NIHSS) score as well as lower mHLA-DR levels, higher IL-6 and LBP-levels at day 1 were associated with poor outcome at 3 months in bivariate analysis. Furthermore, multivariable analysis revealed that lower mHLA-DR expression was associated with poor outcome.
Female sex, older age, atrial fibrillation, SAP, higher NIHSS score, lower mHLA-DR expression and higher IL-6 levels were associated with shorter survival time in bivariate analysis. In multivariable analysis, SAP and higher IL-6 levels on day 1 were associated with shorter survival time.
Conclusions
SAP, lower mHLA-DR-expression and higher IL-6 levels on day one are associated with poor outcome and shorter survival time at 3 months after stroke onset.
Trial registration
www.clinicaltrials.gov,
NCT01079728
, March 3, 2010.
Journal Article
Exact replication: Foundation of science or game of chance?
2019
The need for replication of initial results has been rediscovered only recently in many fields of research. In preclinical biomedical research, it is common practice to conduct exact replications with the same sample sizes as those used in the initial experiments. Such replication attempts, however, have lower probability of replication than is generally appreciated. Indeed, in the common scenario of an effect just reaching statistical significance, the statistical power of the replication experiment assuming the same effect size is approximately 50%-in essence, a coin toss. Accordingly, we use the provocative analogy of \"replicating\" a neuroprotective drug animal study with a coin flip to highlight the need for larger sample sizes in replication experiments. Additionally, we provide detailed background for the probability of obtaining a significant p value in a replication experiment and discuss the variability of p values as well as pitfalls of simple binary significance testing in both initial preclinical experiments and replication studies with small sample sizes. We conclude that power analysis for determining the sample size for a replication study is obligatory within the currently dominant hypothesis testing framework. Moreover, publications should include effect size point estimates and corresponding measures of precision, e.g., confidence intervals, to allow readers to assess the magnitude and direction of reported effects and to potentially combine the results of initial and replication study later through Bayesian or meta-analytic approaches.
Journal Article