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Background: Previous studies have demonstrated that CF (Cystic Fibrosis) prognosis is dependent of three major parameters: FEV1 (Forced Expiratory Pressure in one second), BMI (Body Mass Index) and need of intravenous antibiotic therapy. The CF centres of Frankfurt, Germany, and Moscow, Russia, care for cystic fibrosis patients. We decided to investigate and compare both centers from 1990 to 2015. No comparable study has been published so far.
Method: German patient data was collected from the national cystic fibrosis database “Muko.web”. Missing values were extracted from the Hospital Information System. Russian patient data were taken directly from the medical records in Moscow. In a descriptive statistical analysis with Bias and R Studio the values were compared.
Result: A total of 428 patients from Moscow (217 male, 211 female; 348 (81,3%) were P. aeruginosa positive) and 159 patients from Frankfurt (92 male, 67 female; 137 (86,2%) with P. aeruginosa positive) were compared with regard to P. aeruginosa positivity, BMI, FEV1 and need of intravenous antibiotic therapy. CF patients in Moscow stratified by age groups had lower BMI than CF patients in Frankfurt (age 16-18: p=0,003; age 19-22: p=0,004; age 23-29: p<0,001; age 30-35: p<0,001; age 36-66: p=0,024). In a matching pairs analysis including 100 patients from Frankfurt and 100 patients from Moscow for the year 2015 FEV1 was significantly lower in Moscow patients (p<0,001).
Conclusion: BMI, FEV1 and need of intravenous therapy have significant impact on survival and on quality of life of CF patients. A lower BMI and a lower FEV1 result in a worse survival and determine the prognosis. This study showed a significant difference in prognostic parameters between Frankfurt and Moscow in the crosssectional analysis for the year 2015. A further study should evaluate this difference to show whether this difference will be found over a longer period of time.
MicroRNA miR-181 - a rheostat for TCR signaling in thymic selection and peripheral T-Cell function
(2020)
The selection of T cells during intra-thymic d evelopment is crucial to obtain a functional and simultaneously not self-reactive peripheral T cell repertoire. However, selection is a complex process dependent on T cell receptor (TCR) thresholds that remain incompletely understood. In peripheral T cells, activation, clonal expansion, and contraction of the active T cell pool, as well as other processes depend on TCR signal strength. Members of the microRNA (miRNA) miR-181 family have been shown to be dynamically regulated during T cell development as well as dependent on the activation stage of T cells. Indeed, it has been shown that expression of miR-181a leads to the downregulation of multiple phosphatases, implicating miR-181a as ‘‘rheostat’’ of TCR signaling. Consistently, genetic models have revealed an essential role of miR-181a/b-1 for the generation of unconventional T cells as well as a function in tuning TCR sensitivity in peripheral T cells during aging. Here, we review these broad roles of miR-181 family members in T cell function via modulating TCR signal strength.
MicroRNAs (miRNAs) have emerged as critical posttranscriptional regulators of the immune system, including function and development of regulatory T (Treg) cells. Although this critical role has been firmly demonstrated through genetic models, key mechanisms of miRNA function in vivo remain elusive. Here, we review the role of miRNAs in Treg cell development and function. In particular, we focus on the question what the study of miRNAs in this context reveals about miRNA biology in general, including context-dependent function and the role of individual targets vs. complex co-targeting networks. In addition, we highlight potential technical pitfalls and state-of-the-art approaches to improve the mechanistic understanding of miRNA biology in a physiological context.
Background: Radiotherapy dose and target volume prescriptions for anal squamous cell carcinoma (ASCC) vary considerably in daily practice and guidelines, including those from NCCN, UK, Australasian, and ESMO. We conducted a pattern-of-care survey to assess the patient management in German speaking countries.
Methods: We developed an anonymous questionnaire comprising 18 questions on diagnosis and treatment of ASCC. The survey was sent to 361 DEGRO-associated institutions, including 41 university hospitals, 118 non-university institutions, and 202 private practices.
Results: We received a total of 101 (28%) surveys, including 20 (19.8%) from university, 36 (35.6%) from non-university clinics, and 45 (44.6%) from private practices. A total of 28 (27.8%) institutions reported to treat more than 5 patients with early-stage ASCC and 42 (41.6%) institutions treat more than 5 patients with locoregionally-advanced ASCC per year. Biopsy of suspicious inguinal nodes was advocated in only 12 (11.8%) centers. Screening for human immunodeficiency virus (HIV) is done in 28 (27.7%). Intensity modulated radiotherapy or similar techniques are used in 97%. The elective lymph node dose ranged from 30.6 Gy to 52.8 Gy, whereas 87% prescribed 50.4–55. 8 Gy (range: 30.6 to 59.4 Gy) to the involved lymph nodes. The dose to gross disease of cT1 or cT2 ASCC ranged from 50 to ≥60 Gy. For cT3 or cT4 tumors the target dose ranged from 54 Gy to more than 60 Gy, with 76 (75.2%) institutions prescribing 59.4 Gy. The preferred concurrent chemotherapy regimen was 5-FU/Mitomycin C, whereas 6 (6%) prescribed Capecitabine/Mitomycin C. HIV-positive patients are treated with full-dose CRT in 87 (86.1%) institutions. First assessment for clinical response is reported to be performed at 4–6 weeks after completion of CRT in 2 (2%) institutions, at 6–8 weeks in 20 (19.8%), and 79 (78%) institutions wait up to 5 months.
Conclusions: We observed marked differences in radiotherapy doses and treatment technique in patients with ASCC, and also variable approaches for patients with HIV. These data underline the need for an consensus treatment guideline for ASCC.
Purpose: Perfusion-weighted MRI (PWI) and O-(2-[18F]fluoroethyl-)-l-tyrosine ([18F]FET) PET are both applied to discriminate tumor progression (TP) from treatment-related changes (TRC) in patients with suspected recurrent glioma. While the combination of both methods has been reported to improve the diagnostic accuracy, the performance of a sequential implementation has not been further investigated. Therefore, we retrospectively analyzed the diagnostic value of consecutive PWI and [18F]FET PET.
Methods: We evaluated 104 patients with WHO grade II–IV glioma and suspected TP on conventional MRI using PWI and dynamic [18F]FET PET. Leakage corrected maximum relative cerebral blood volumes (rCBVmax) were obtained from dynamic susceptibility contrast PWI. Furthermore, we calculated static (i.e., maximum tumor to brain ratios; TBRmax) and dynamic [18F]FET PET parameters (i.e., Slope). Definitive diagnoses were based on histopathology (n = 42) or clinico-radiological follow-up (n = 62). The diagnostic performance of PWI and [18F]FET PET parameters to differentiate TP from TRC was evaluated by analyzing receiver operating characteristic and area under the curve (AUC).
Results: Across all patients, the differentiation of TP from TRC using rCBVmax or [18F]FET PET parameters was moderate (AUC = 0.69–0.75; p < 0.01). A rCBVmax cutoff > 2.85 had a positive predictive value for TP of 100%, enabling a correct TP diagnosis in 44 patients. In the remaining 60 patients, combined static and dynamic [18F]FET PET parameters (TBRmax, Slope) correctly discriminated TP and TRC in a significant 78% of patients, increasing the overall accuracy to 87%. A subgroup analysis of isocitrate dehydrogenase (IDH) mutant tumors indicated a superior performance of PWI to [18F]FET PET (AUC = 0.8/< 0.62, p < 0.01/≥ 0.3).
Conclusion: While marked hyperperfusion on PWI indicated TP, [18F]FET PET proved beneficial to discriminate TP from TRC when PWI remained inconclusive. Thus, our results highlight the clinical value of sequential use of PWI and [18F]FET PET, allowing an economical use of diagnostic methods. The impact of an IDH mutation needs further investigation.
Bipolar disorder (BD) and major depressive disorder (MDD) are severe mood disorders that belong to the most debilitating diseases worldwide. Differentiating both mood disorders often poses a major clinical challenge, leading to frequent misdiagnoses. Objective biomarkers able to differentiate individuals with BD and MDD therefore represent a psychiatric research field of utmost importance. Recent studies have applied resting-state fMRI paradigms and found promising results differentiating both disorders based on the acquired data. However, most of these studies have focused their efforts on acutely depressed patients. Thus, it remains unclear whether the aberrations remain in a symptomless disease state.
The here presented study addresses these issues by evaluating the ability to differentiate both disorders from one another by conducting a between-group comparison of functional brain network connectivity (FNC) obtained from resting-state fMRI data. Data were collected from 20 BD, 15 MDD patients and 30 age- and gender-matched healthy controls (HC). Graph theoretical analyses were applied to detect differences in functional network organization between the groups on a global and regional network level.
Network analysis detected frontal, temporal and subcortical nodes in emotion regulation areas such as the limbic system and associated regions exhibiting significant differences in network integration and segregation in BD compared to MDD patients and HC. Participants with MDD and HC only differed in frontal and insular network centrality.
These results indicate that a significantly altered brain network topology in the limbic system might be a trait marker specific to BD. Brain network analysis in these regions may therefore be used to differentiate euthymic BD not only from HC but also from patients with MDD.
Current research on medical biomaterials have shown that the physical and chemical characteristics of biomaterials determine the body inflammatory cellular reaction after their implantation. The aim of this study was to evaluate the individual effects of the physical characteristics over the initial biomaterial-cellular interaction and the inflammatory cellular reaction. For this purpose, an equine-derived collagen hemostatic sponge (E-CHS) was modified by pressing and evaluated using ex vivo, in vitro and in vivo methods.
The E-CHS was pressed by applying constant pressure (6.47± 0.85 N) for 2 min using a sterile stainless-steel cylinder and cut in segments of 1cm2. Subsequently, E-CHS and the pressed equine-derived collagen hemostatic sponge (P-E-CHS) were studied as two independent biomaterials and compared to a control group (CG).
A blood concentrate containing inflammatory cells known as platelet rich fibrin (PRF) was used to mimic the initial biomaterial-cell interaction and to measure the absorption coefficient of the biomaterials to liquid PRF (iPAC). Additionally, the biomaterials were cultivated together with PRF for 3 and 6 days to measure the induction of pro-inflammatory cytokines (TNF-α and IL-8). The results were obtained through enzyme-linked immunosorbent assay (ELISA) and histological methods. PRF cultivated without biomaterials served as the CG. Additionally, the biomaterials were evaluated in vivo using a subcutaneous model in Wistar rats and compared to sham operated animals (CG) representing physiologic wound healing. After 3, 15 and 30 days, the explanted samples were evaluated using histochemical and immunohistochemical (IHC) staining using the following markers: CD68 (pan macrophages), CCR7 (pro-inflammatory macrophages, M1), CD206 (pro-wound healing macrophages, M2) and α-Smooth Muscle Actin (α-SMA; vessel identification).
After the mixture of liquid PRF with both biomaterials for 15 minutes, the ex vivo results showed that E-CHS was penetrated by cells, whereas P-E-CHS was cell-occlusive. Additionally, P-E-CHS induced a higher release of pro-inflammatory cytokines compared to liquid PRF alone (CG) and E-CHS after 3 days (P< 0.05). Although the biomaterial was pressed, the difference of the iPAC value did not show statistical differences. In vivo, the CG induced at day 3 a higher inflammatory response compared to the experimental groups (EG) (P< 0.05). The intergroup comparison showed that P-E-CHS induced a higher presence of macrophages (CD68+/CC7+) compared to E-CHS at day 3 (P< 0.05). Only CD68+/CCR7+ mononuclear cells (MNCs) were observed without multinucleated giant cells (MNGCs). After 15 days, the presence of macrophages (CD68+ P<0.01 /CCR7+ P<0.001 /CD206+ P<0.05) reduced considerably in the CG. On the contrary, the inflammatory response increased in the EGs (CD68+/CCR7+). The intergroup comparison showed that this increment was statistically significant when comparing E-CHS and P-E-CHS to the CG at day 15 (P<0.01 and P< 0.05 respectively). At this time point, a reduced number of MNGCs were observed in the EGs. In the CG no MNGCs were observed. Furthermore, E-CHS showed a faster degradation rate and was fully invaded by cells and vessels formed in its interior region. On the other hand, P-E-CHS remained occlusive to cell penetration and vessels were formed only in the periphery. After 30 days, the cellular reaction shifted to a higher number of M2 macrophages (CD260+) in all groups and a reduced presence of CD68+ and CCR7+ MNCs. Both biomaterials degraded and only small fragments were found in the implantation bed surrounded by MNGCs (CCR7+).
These results are of high clinical relevance and show that changes in biomaterial properties have a significant impact on their interaction with the body. They also serve as insight into the possibility to develop versatile biomaterials with different applications. For example, E-CHs can be applied to support hemostasis in a bleeding alveolar socket and P-E-CHs by being cell occlusive and having a delayed degradation rate can be applied for guided bone and tissue regeneration.
Objective: To evaluate the incidence and risk factors of generalized convulsive seizure (GCS)-related fractures and injuries during video-EEG monitoring.
Methods: We analyzed all GCSs in patients undergoing video-EEG-monitoring between 2007 and 2019 at epilepsy centers in Frankfurt and Marburg in relation to injuries, falls and accidents associated with GCSs. Data were gathered using video material, EEG material, and a standardized reporting form.
Results: A total of 626 GCSs from 411 patients (mean age: 33.6 years; range 3–74 years; 45.0% female) were analyzed. Severe adverse events (SAEs) such as fractures, joint luxation, corneal erosion, and teeth loosening were observed in 13 patients resulting in a risk of 2.1% per GCS (95% CI 1.2–3.4%) and 3.2% per patient (95% CI 1.8–5.2%). Except for a nasal fracture due to a fall onto the face, no SAEs were caused by falls, and all occurred in patients lying in bed without evidence of external trauma. In seven patients, vertebral body compression fractures were confirmed by imaging. This resulted in a risk of 1.1% per GCS (95% CI 0.5–2.2%) and 1.7% per patient (95% CI 0.8–3.3%). These fractures occurred within the tonic phase of a GCS and were accompanied by a characteristic cracking noise. All affected patients reported back pain spontaneously, and an increase in pain on percussion of the affected spine section.
Conclusions: GCSs are associated with a substantial risk of fractures and shoulder dislocations that are not associated with falls. GCSs accompanied by audible cracking, and resulting in back pain, should prompt clinical and imaging evaluations.
miR-142-3p expression is predictive for severe traumatic brain injury (TBI) in trauma patients
(2020)
Background: Predictive biomarkers in biofluids are the most commonly used diagnostic method, but established markers in trauma diagnostics lack accuracy. This study investigates promisingmicroRNAs(miRNA)releasedfromaffectedtissueafterseveretraumathathavepredictive values for the effects of the injury.
Methods: A retrospective analysis of prospectively collected data and blood samples of n = 33 trauma patients (ISS≥16) is provided. Levels of miR-9-5p, -124-3p, -142-3p, -219a-5p, -338-3pand-423-3p inseverelyinjuredpatients (PT)withouttraumatic braininjury (TBI) or with severe TBI (PT + TBI) and patients with isolated TBI (isTBI) were measured within 6 h after trauma.
Results: The highest miR-423-3p expression was detected in patients with severe isTBI, followed by patients with PT + TBI, and lowest levels were found in PT patients without TBI (2−∆∆Ct,p = 0.009). ApositivecorrelationbetweenmiR-423-3plevelandincreasingAIShead (p = 0.001) and risk of mortality (RISC II, p = 0.062) in trauma patients (n = 33) was found. ROC analysis of miR-423-3p levels revealed them as statistically significant to predict the severity of brain injury in trauma patients (p = 0.006). miR-124-3p was only found in patients with severe TBI, miR-338-3p was shown in all trauma groups. miR-9-5p, miR-142-3p and miR-219a-5p could not be detected in any of the four groups. Conclusion: miR-423-3p expression is significantly elevated after isolated traumatic braininjuryandpredictableforsevereTBIinthefirsthoursaftertrauma. miR-423-3pcouldrepresent a promising new biomarker to identify severe isolated TBI.
The aim of this study is to provide a systematic assessment of the influence of the position on the arterial input function (AIF) for perfusion quantification. In 39 patients with a wide range of left ventricular function the AIF was determined using a diluted contrast bolus of a cardiac magnetic resonance imaging in three left ventricular levels (basal, mid, apex) as well as aortic sinus (AoS). Time to peak signal intensities, baseline corrected peak signal intensity and upslopes were determined and compared to those obtained in the AoS. The error induced by sampling the AIF in a position different to the AoS was determined by Fermi deconvolution. The time to peak signal intensity was strongly correlated (r2 > 0.9) for all positions with a systematic earlier arrival in the basal (− 2153 ± 818 ms), the mid (− 1429 ± 928 ms) and the apical slice (− 450 ± 739 ms) relative to the AoS (all p < 0.001). Peak signal intensity as well as upslopes were strongly correlated (r2 > 0.9 for both) for all positions with a systematic overestimation in all positions relative to the AoS (all p < 0.001 and all p < 0.05). Differences between the positions were more pronounced for patients with reduced ejection fraction. The error of averaged MBF quantification was 8%, 13% and 27% for the base, mid and apex. The location of the AIF significantly influences core parameters for perfusion quantification with a systematic and ejection fraction dependent error. Full quantification should be based on obtaining the AIF as close as possible to the myocardium to minimize these errors.