Presence of procoagulant peripheral blood mononuclear cells in severe COVID-19 patients relate to ventilation perfusion mismatch and precede pulmonary embolism.

PURPOSE: Pulmonary emboli (PE) contribute substantially to coronavirus disease 2019 (COVID-19) related mortality and morbidity. Immune cell-mediated hyperinflammation drives the procoagulant state in COVID-19 patients, resulting in immunothrombosis. To study the role of peripheral blood mononuclear cells (PBMC) in the procoagulant state of COVID-19 patients, we performed a functional bioassay and related outcomes to the occurrence of PE. Secondary aims were to relate this functional assay to plasma D-dimer levels, ventilation perfusion mismatch and TF expression on monocyte subsets. METHODS: PBMC from an ICU biobank were obtained from 20 patients with a computed tomography angiograph (CTA) proven PE and compared to 15 COVID-19 controls without a proven PE. Functional procoagulant properties of PBMC were measured using a modified fibrin generation time (MC-FGT) assay. Tissue factor (TF) expression on monocyte subsets were measured by flow cytometry. Additional clinical data were obtained from patient records including end-tidal to arterial carbon dioxide gradient. RESULTS: MC-FGT levels were highest in the samples taken closest to the PE detection, similar to the end-tidal to arterial carbon dioxide gradient (ETCO2 - PaCO2), a measurement to quantify ventilation-perfusion mismatch. In patients without proven PE, peak MC-FGT relates to an increase in end-tidal to arterial carbon dioxide gradient. We identified non-classical, CD16 positive monocytes as the subset with increased TF expression. CONCLUSION: We show that the procoagulant state of PBMC could aid in early detection of PE in COVID-19 ICU patients. Combined with end-tidal to ETCO2 - PaCO2 gradient, these tests could improve early detection of PE on the ICU.

Comprehensive pharmaceutical care to prevent drug-related readmissions of dependent-living elderly patients: a randomized controlled trial.

BACKGROUND: Elderly patients are vulnerable to adverse drug reactions (ADRs). Drug-related readmissions (DRRs) can be a major consequence of ADR. Therefore, this study aimed to investigate the effects of a ward-based, comprehensive pharmaceutical care service on the occurrence of DRRs as the endpoint in dependent-living elderly patients. METHODS: A randomized, controlled trial was performed at a German University Hospital. Patients fulfilling the following criteria were eligible: admission to a cooperating ward, existing drug therapy at admission, 65 years of age and older, home-care or nursing home residents in ambulatory care, and a minimum hospital stay of three days. Patients received either standard care (control group) or pharmaceutical care (intervention group). Follow-up consultations were conducted for each patient at 1, 8, 26, and 52 weeks after discharge. The time to DRR was defined as the primary outcome measure and was analysed using the log-rank test. The Cox-proportional hazard model was used for risk factor analysis. RESULTS: Sixty patients (n = 31 intervention group, n = 29 control group) participated in the study. For patients in the intervention group, the median time to DRR was prolonged; however, the level of statistical significance was not reached (log-rank test P = 0.068; HR = 3.28, P = 0.086). When the risk factors 'age' or 'length of stay on the ward' were added to the Cox proportional hazard model, patients in the control group exhibited a significantly higher risk of experiencing a DRR than patients of the intervention group (HR = 4.62; P = 0.028 including age and HR = 5.76; P = 0.033 including length of stay on the ward). CONCLUSIONS: Our findings demonstrate the successful implementation of ward-based, comprehensive pharmaceutical care for dependent-living elderly. Despite a low participation rate, which led to an underpowered study, the results provide a preliminary efficacy signal and effect size estimates to power a definitive trial. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT01578525 , prospectively registered April 13, 2012.

Dysregulation of lysophosphatidic acids in multiple sclerosis and autoimmune encephalomyelitis.

Bioactive lipids contribute to the pathophysiology of multiple sclerosis. Here, we show that lysophosphatidic acids (LPAs) are dysregulated in multiple sclerosis (MS) and are functionally relevant in this disease. LPAs and autotaxin, the major enzyme producing extracellular LPAs, were analyzed in serum and cerebrospinal fluid in a cross-sectional population of MS patients and were compared with respective data from mice in the experimental autoimmune encephalomyelitis (EAE) model, spontaneous EAE in TCR1640 mice, and EAE in Lpar2 -/- mice. Serum LPAs were reduced in MS and EAE whereas spinal cord LPAs in TCR1640 mice increased during the 'symptom-free' intervals, i.e. on resolution of inflammation during recovery hence possibly pointing to positive effects of brain LPAs during remyelination as suggested in previous studies. Peripheral LPAs mildly re-raised during relapses but further dropped in refractory relapses. The peripheral loss led to a redistribution of immune cells from the spleen to the spinal cord, suggesting defects of lymphocyte homing. In support, LPAR2 positive T-cells were reduced in EAE and the disease was intensified in Lpar2 deficient mice. Further, treatment with an LPAR2 agonist reduced clinical signs of relapsing-remitting EAE suggesting that the LPAR2 agonist partially compensated the endogenous loss of LPAs and implicating LPA signaling as a novel treatment approach. Graphical summary of lysophosphatidic signaling in multiple sclerosis.

Evaluation of a web-based weight loss intervention in overweight cancer survivors aged 50 years and younger.

PURPOSE: Half of adult cancer survivors under age 50 years are obese. Excess body weight is associated with cancer recurrence, and effective weight loss interventions for younger cancer survivors are needed. Commercially available, online weight loss programmes are readily accessible, but few have been studied in this population. This study employed a single-arm, pre-post intervention (baseline-6 month/baseline-12 month comparisons) to preliminarily explore feasibility, efficacy and safety of an online, commercially available weight loss programme in breast (n = 30) and testicular (n = 16) cancer survivors under age 50 years. METHODS: The intervention included three daily components: exercise, nutritional/behavioural modification strategies and health lessons. Intention-to-treat and completers analyses were conducted. Feasibility was measured by participation (number of participants enrolled/number screened), retention (number of participants attending 6/12 month study visit/number of enrolled) and self-reported adherence rates (average of mean percent adherence to each of the three intervention components). Efficacy was assessed by changes in initial weight (percent weight loss). Safety was assessed by adverse events. RESULTS: The mean participation rate was 42%. The retention rate was 59% at 6 and 49% at 12 months. The adherence rate for all participants (completers/dropouts/lost-to-follow-up) was 50.1% at 6 and 44% at 12 months. Completers reported adherence rates of 68% at 12 months. Study participants lost 5.3% body weight at 12 months; completers lost 9%. Only three unexpected adverse events (unrelated to the intervention) were reported. CONCLUSION: Clinically significant weight loss was observed, although retention rates were low. Findings generally support preliminary feasibility, efficacy and safety of this online weight loss programme, and future randomized control trials should be explored.

Biodegradable polymeric stents for vascular application in a porcine carotid artery model: English version.

Over the past years the development of biodegradable polymeric stents has made great progress; nevertheless, essential problems must still be solved. Modifications in design and chemical composition should optimize the quality of biodegradable stents and remove the weaknesses. New biodegradable poly-L-lactide/poly-4-hydroxybutyrate (PLLA/P4HB) stents and permanent 316L stents were implantedendovascularly into both common carotid arteries of 10 domestic pigs. At 4 weeks following implantation, computed tomography (CT) angiography was carried out to identify the distal degree of stenosis. The PLLA/P4HB group showed a considerably lower distal degree of stenosis by additional oral application of atorvastatin (mean 39.81 ± 8.57 %) compared to the untreated PLLA/P4HB group without atorvastatin (mean 52.05 ± 5.80 %). The 316L stents showed no differences in the degree of distal stenosis between the group treated with atorvastatin (mean 44.21 ± 2.34 %) and the untreated group (mean 35.65 ± 3.72 %). Biodegradable PLLA/P4HB stents generally represent a promising approach to resolving the existing problems in the use of permanent stents. Restitutio ad integrum is only achievable if a stent is completely degraded.

Statistical Evaluation of HTS Assays for Enzymatic Hydrolysis of ß-Keto Esters.

ß-keto esters are used as precursors for the synthesis of ß-amino acids, which are building blocks for some classes of pharmaceuticals. Here we describe the comparison of screening procedures for hydrolases to be used for the hydrolysis of ß-keto esters, the first step in the preparation of ß-amino acids. Two of the tested high throughput screening (HTS) assays depend on coupled enzymatic reactions which detect the alcohol released during ester hydrolysis by luminescence or absorption. The third assay detects the pH shift due to acid formation using an indicator dye. To choose the most efficient approach for screening, we assessed these assays with different statistical methods-namely, the classical Z'-factor, standardized mean difference (SSMD), the Kolmogorov-Smirnov-test, and t-statistics. This revealed that all three assays are suitable for HTS, the pH assay performing best. Based on our data we discuss the explanatory power of different statistical measures. Finally, we successfully employed the pH assay to identify a very fast hydrolase in an enzyme-substrate screening.

Multiple rodent models and behavioral measures reveal unexpected responses to FTY720 and DMF in experimental autoimmune encephalomyelitis.

Experimental autoimmune encephalomyelitis (EAE) is a widely-used rodent model for multiple sclerosis (MS), but a single model can hardly capture all features of MS. We investigated whether behavioral parameters in addition to clinical motor function scores could be used to assess treatment efficacy during score-free intervals in the relapsing-remitting EAE model in SJL/J mice. We studied the effects of the clinical reference compounds FTY720 (fingolimod, 0.5mg/kg/day) and dimethyl fumarate (DMF, 20-30 mg/kg/day) on clinical scores in several rodent EAE models in order to generate efficacy profiles. SJL/J mice with relapsing-remitting EAE were studied using behavioral tests, including rotarod, gait analysis, locomotor activity and grip strength. SJL/J mice were also examined according to Crawley's sociability and preference for social novelty test. Prophylactic treatment with FTY720 prevented clinical scores in three of the four EAE rodent models: Dark Agouti (DA) and Lewis rats and C57BL/6J mice. Neither prophylactic nor late-therapeutic treatment with FTY720 reduced clinical scores or reversed deficits in the rotarod test in SJL/J mice, but we observed effects on motor functions and sociability in the absence of clinical scores. Prophylactic treatment with FTY720 improved the gait of SJL/J mice whereas late-therapeutic treatment improved manifestations of reduced social (re)cognition or preference for social novelty. DMF was tested in three EAE models and did not improve clinical scores at the dose used. These data indicate that improvements in behavioral deficits can occur in absence of clinical scores, which indicate subtle drug effects and may have translational value for human MS.

Pro-inflammatory obesity in aged cannabinoid-2 receptor-deficient mice.

BACKGROUND AND OBJECTIVES: Cannabinoid-1 receptor signaling increases the rewarding effects of food intake and promotes the growth of adipocytes, whereas cannabinoid-2 receptor (CB2) possibly opposes these pro-obesity effects by silencing the activated immune cells that are key drivers of the metabolic syndrome. Pro- and anti-orexigenic cannabimimetic signaling may become unbalanced with age because of alterations of the immune and endocannabinoid system. METHODS: To specifically address the role of CB2 for age-associated obesity, we analyzed metabolic, cardiovascular, immune and neuronal functions in 1.2-1.8-year-old CB2(-/-) and control mice, fed with a standard diet and assessed effects of the CB2 agonist, HU308, during high-fat diet (HFD) in 12-16-week-old mice. RESULTS: The CB2(-/-) mice were obese with hypertrophy of visceral fat, immune cell polarization toward pro-inflammatory subpopulations in fat and liver and hypertension, as well as increased mortality despite normal blood glucose. They also developed stronger paw inflammation and a premature loss of transient receptor potential responsiveness in primary sensory neurons, a phenomenon typical for small fiber disease. The CB2 agonist HU308 prevented HFD-evoked hypertension, reduced HFD-evoked polarization of adipose tissue macrophages toward the M1-like pro-inflammatory type and reduced HFD-evoked nociceptive hypersensitivity, but had no effect on weight gain. CONCLUSIONS: CB2 agonists may fortify CB2-mediated anti-obesity signaling without the risk of anti-CB1-mediated depression that caused the failure of rimonabant.

[Coupled Analysis of Fluid-Structure Interaction of a Micro-Mechanical Valve for Glaucoma Drainage Devices]. / Gekoppelte Analyse der Fluid-Struktur-Interaktion eines mikromechanischen Ventils für Glaukomdrainageimplantate.

BACKGROUND: Glaucoma is the leading cause of irreversible blindness worldwide. In therapeutically refractory cases, alloplastic glaucoma drainage devices (GDD) are being increasingly used to decrease intraocular pressure. Current devices are mainly limited by fibrotic encapsulation and postoperative hypotension. Preliminary studies have described the development of a glaucoma microstent to control aqueous humour drainage from the anterior chamber into the suprachoroidal space. One focus of these studies was on the design of a micro-mechanical valve placed in the anterior chamber to inhibit postoperative hypotension. The present report describes the coupled analysis of fluid-structure interaction (FSI) as basis for future improvements in the design micro-mechanical valves. MATERIALS AND METHODS: FSI analysis was carried out with ANSYS 14.5 software. Solid and fluid geometry were combined in a model, and the corresponding material properties of silicone (Silastic Rx-50) and water at room temperature were assigned. The meshing of the solid and fluid domains was carried out in accordance with the results of a convergence study with tetrahedron elements. Structural and fluid mechanical boundary conditions completed the model. The FSI analysis takes into account geometric non-linearity and adaptive remeshing to consider changing geometry. RESULTS: A valve opening pressure of 3.26 mmHg was derived from the FSI analysis and correlates well with the results of preliminary experimental fluid mechanical studies. Flow resistance was calculated from non-linear pressure-flow characteristics as 8.5 × 10(-3) mmHg/µl  · min(-1) and 2.7 × 10(-3) mmHg/µl  · min(-1), respectively before and after valve opening pressure is exceeded. FSI analysis indicated leakage flow before valve opening, which is due to the simplified model geometry. CONCLUSIONS: The presented bidirectional coupled FSI analysis is a powerful tool for the development of new designs of micro-mechanical valves for GDD and may help to minimise the time and cost expended on manufacturing and testing prototypes. Further optimisation of the FSI model is expected to ensure further convergence between the simulation and the results of experimental investigations.

Wide cleft between theory and practice: medical students' perception of their education in patient and medication safety.

In medicine today, future doctors are expected to ensure patient safety. Yet medical students often feel uncertain if they can meet these high expectations. This study aims to quantify the perceptions of medical students regarding the actual quality of their education in the fields of patient safety and, in particular, medication safety. A questionnaire was designed and distributed to about 100 upper-level medical students. The students had to respond to 12 questions regarding the following categories: 1) familiarity with patient safety and/or medication safety; 2) personal experience in high-risk clinical situations; and 3) perceived relevance of knowledge in the area of patient and medication Safety for clinical practice. Of the respondents 42.1% and 36.8% had delved into the topic patient safety and medication safety, respectively. In clinical practice 88.2% of respondents had experienced a high-risk situation for patients. Regarding patient safety and medication safety, respectively, 82.9% and 85.3% of the respondents found these topics to be particularly relevant to their clinical practice. This study has shown that there is a measurable discrepancy between the students' perceived quality of their medical education and their feelings that they are well prepared to cope with severe clinical challenges.

[Molecular pathology of soft tissue tumors: Contribution to diagnosis and therapy prediction]. / Molekularpathologie der Weichgewebstumoren: Beitrag zur Diagnostik und Therapieprädiktion.

Soft tissue tumors are often challenging for pathologists on the basis of morphology alone; therefore, tumor-specific chromosomal aberrations, such as translocations and fusions, amplifications or deletions can be diagnostically useful. Fluorescence in situ hybridization is widely used for the detection of most aberrations in routine diagnostics. Furthermore, reverse transcriptase PCR, sequencing and specific immunohistochemical assays are also applied. Next generation sequencing has already contributed to the identification of hitherto unknown aberrations. Molecular pathology is mainly used in sarcomas to discriminate between different tumor entities. In terms of personalized therapy and targeted treatment, molecular pathology can be utilized to detect predictive markers.

[Monstrous scrotal leiomyoma: case report and literature survey]. / Monströses scrotales Leiomyom; Fallbericht und Überblick über die Literatur.

The scrotal leiomyoma is a rare benign tumour, deriving from the smooth muscle. This tumour entity constitutes a differential diagnosis to malignant testicular tumours. Up to now, only 8 cases have been reported in the literature. We report on a 63-year-old European patient, presenting in our clinic for further treatment with a now monstrous mass of the left testis (about 8 kg) that has been growing for about 30 years, After partial scrotalectomy and orchiectomy pathological analysis confirmed a left-sided leiomyoma of the testicular/paratestical tissue. This case shows that even rare tumours should be included in the differential diagnosis of a testicular tumour.

Biodegradable polymeric coatings on cochlear implant surfaces and their influence on spiral ganglion cell survival.

To improve the electrode-nerve interface of cochlear implants (CI), the role of poly(L-lactide) (PLLA) and poly(4-hydroxybutyrate) (P(4HB)) as potential coating matrices for CI was assessed both in vitro and in vivo in terms of degradation behavior and effects on spiral ganglion neurons, the main target of the electrical stimulation with a CI. Growth rates of fibroblasts on the polymers were investigated and a direct-contact test with freshly isolated spiral ganglion cells (SGC) was performed. In addition, the effects of the polymer degradation inside the inner ear were evaluated in vivo. The polymer degradation was assessed by use of scanning electron microscopy in combination with an energy-dispersive X-ray analysis. In vitro, no influence of the polymers was detected on fibroblasts' viability and on SGC survival rate. In vivo, SGC density was decreased only 6 months after implantation in the basal and middle turns of the cochlea in comparison to normal-hearing animals but not between implanted groups (coated or uncoated). The analysis of the electrode models showed that in vivo P(4HB) is characterized by a gradual degradation completed after 6 months; whereas, the PLLA coatings burst along their longitudinal axis but showed only little degradation within the same time frame. In conclusion, both polymers seem to justify further evaluation as possible coating for CI electrodes. Of the two options, due to its excellent coating adhesion/stability and optimal degradation behavior, P(4HB) may prove to be the more promising biodegradable polymer for designing a drug delivery system from the surface of CI electrodes.

Experimental investigation of modern and established carotid stents.

PURPOSE: The design and material determine the mechanical properties of stents. In vitro parameters such as radial force, flexibility and wall adaptation of different stents were investigated in order to obtain evidence for clinical use. MATERIALS AND METHODS: A total of 8 stents, including 2 hybrid stents with a combination of closed/open-cell design (Sinus Carotid RX, Cristallo Ideale), 3 closed-cell stents (Adapt, Carotid Wallstent, Xact Carotid) and 3 open-cell stents (Vivexx Carotid, Protégé Rx and Precise) with a diameter of 8 mm and a length of 40 mm, were investigated. The radial force, the bending stiffness of the stent system and of the stent, and the collapse pressure were measured. The wall adjustment of the stents was documented by fluoroscopy and assessed in a step and curve model. RESULTS: The bending stiffness of the stent systems declined significantly in the expanded state, whereby the Xact Carotid stent showed the highest value (291.1 N/mm2) in contrast to 31.6-39.4 N/mm2 for the Sinus Carotid and Cristallo Ideale. The radial force on expansion of the stents to 7 mm was lowest for the Adapt (0.009 N/mm) and highest for the Precise (0.068 N/mm). The collapse pressure was highest for the Carotid Wallstent (0.48 bar), compared with the other stents (0.1 - 0.2 bar). The best wall adjustment in the curve model was shown by the Precise, the Sinus Carotid Rx and the Vivexx Carotid Stent. The diameter change from 5 to 7 mm was smoothly adapted by the Cristallo Ideale and the Carotid Wallstent. The Adapt showed poor vessel wall adaptation in both step and curved vessels. CONCLUSION: As a result of their design, the Sinus Carotid Rx and the Cristallo Ideale show the best wall adjustment, with comparable radial force and high flexibility, whereby the Cristallo Ideale has the advantage that it has a closed-cell design in the middle third of the stent. The other stents should be taken into consideration with their specifications in individual cases. KEY POINTS: The investigation of carotid stents provides an objective comparison of mechanical properties. Conclusions about the respective optimum uses of stents can be drawn from this. The hybrid stents show a good balance of properties for wide applicability. Citation Format: • Wissgott C, Schmidt W, Behrens P et al. Experimental Investigation of Modern and Established Carotid Stents. Fortschr Röntgenstr 2014; 186: 157 - 165.

[Reliability and safety of intravitreal Ozurdex injections. The ZERO study]. / Zuverlässigkeit und Sicherheit von intravitrealen Ozurdex-Injektionen. Die ZERO-Studie.

BACKGROUND: Since July 2010 Ozurdex® is approved in Germany for treatment of macular edema from retinal vein occlusion (RVO). The objective of this observational study was a systemic summary and analysis of clinical experience regarding complications and side effects of intravitreal administration of dexamethasone. PATIENTS AND METHODS: In a retrospective, multicenter study conducted at 10 centers, 342 eyes with RVO were treated with intravitreal dexamethasone (Ozurdex®, Allergan). After treatment the patients were followed-up over a period of 8 months and intraoperative, perioperative and postoperative complications, such as elevated intraocular pressure and dislocation of implants were systematically recorded. RESULTS: No infections, endophthalmitis, perioperative hypotension, intraoperative lens injuries or retinal detachment occurred. Elevated intraocular pressure was the most common complication accounting for nearly 20 %. In 9 % of patients the intraocular pressure increased by more than 10 mmHg compared to baseline and in 6 patients to > 35 mmHg. In cases of known glaucoma intraocular pressure elevation was not significantly more frequent compared to non-glaucoma patients. In four cases a progression of lens opacity led to phacoemulsification and two implant dislocations in the anterior chamber required surgical repositioning in the vitreous cavity. In two cases a postinterventional macular hole was observed. CONCLUSIONS: In the clinical routine Ozurdex treatment has proven to be a therapy method with minimal side effects. In Ozurdex administration intraocular pressure elevation was observed as the most common side effect; however, this generally did not require surgical intervention. Caution is advised in patients with an anterior chamber lens and iridectomy. Macular holes as a rare complication might result from vitreous traction during the administration process. In summary, even in the clinical routine application of Ozurdex the complication rate was not higher than in registration studies.