Mimicking the Human Tympanic Membrane: The Significance of Scaffold Geometry

The human tympanic membrane (TM) captures sound waves from the environment and transforms them into mechanical motion. The successful transmission of these acoustic vibrations is attributed to the unique architecture of the TM. However, a limited knowledge is available on the contribution of its discrete anatomical features, which is important for fabricating functional TM replacements. This work synergizes theoretical and experimental approaches toward understanding the significance of geometry in tissue-engineered TM scaffolds. Three test designs along with a plain control are chosen to decouple some of the dominant structural elements, such as the radial and circumferential alignment of the collagen fibrils. In silico models suggest a geometrical dependency of their mechanical and acoustical responses, where the presence of radially aligned fibers is observed to have a more prominent effect compared to their circumferential counterparts. Following which, a hybrid fabrication strategy combining electrospinning and additive manufacturing has been optimized to manufacture biomimetic scaffolds within the dimensions of the native TM. The experimental characterizations conducted using macroindentation and laser Doppler vibrometry corroborate the computational findings. Finally, biological studies with human dermal fibroblasts and human mesenchymal stromal cells reveal a favorable influence of scaffold hierarchy on cellular alignment and subsequent collagen deposition

Untersuchungen der Uferstabilität der Tideelbe im Projekt Elb-Stabil

Über Messungen auf der Meso- und Mikroskala sollen Parameter bestimmt werden, die mittels einer Pedotransfer-funktion die Bodenstabilität an der Tideelbe vorherzusagen ermöglicht

Ribonuclease 1 attenuates septic cardiomyopathy and cardiac apoptosis in a murine model of polymicrobial sepsis.

Septic cardiomyopathy is a life-threatening organ dysfunction caused by sepsis. Ribonuclease 1 (RNase 1) belongs to a group of host-defense peptides that specifically cleave extracellular RNA (eRNA). The activity of RNase1 is inhibited by ribonuclease-inhibitor 1 (RNH1). The role of RNase 1 in septic cardiomyopathy and associated cardiac apoptosis, however, is completely unknown. Here, we showed that sepsis resulted in a significant increase in RNH1 and eRNA serum levels compared to those of healthy subjects (p < 0.05). Treatment with RNase 1 resulted in a significant decrease of apoptosis, induced by the intrinsic pathway, and TNF expression in murine cardiomyocytes exposed to either necrotic cardiomyocytes or serum of septic patients for 16 h (p < 0.05). Furthermore, treatment of septic mice with RNase 1 resulted in a reduction in cardiac apoptosis, TNF expression and septic cardiomyopathy (p < 0.05). These data demonstrate that eRNA plays a crucial role in the pathophysiology of the organ (cardiac) dysfunction in sepsis and RNase and RNH1 may be new therapeutic targets/strategies to reduce the cardiac injury and dysfunction caused by sepsis

Meeting nutritional targets of critically ill patients by combined enteral and parenteral nutrition: review and rationale for the EFFORTcombo trial.

While medical nutrition therapy is an essential part of the care for critically ill patients, uncertainty exists about the right form, dosage, timing and route in relation to the phases of critical illness. As enteral nutrition (EN) is often withheld or interrupted during the intensive care unit (ICU) stay, combined EN and parenteral nutrition (PN) may represent an effective and safe option to achieve energy and protein goals as recommended by international guidelines. We hypothesise that critically ill patients at high nutritional risk may benefit from such a combined approach during their stay on the ICU. Therefore, we aim to test if an early combination of EN and high-protein PN (EN+PN) is effective in reaching energy and protein goals in patients at high nutritional risk, while avoiding overfeeding. This approach will be tested in the here-presented EFFORTcombo trial. Nutritionally high-risk ICU patients will be randomised to either high (≥2·2 g/kg per d) or low protein (≤1·2 g/kg per d). In the high protein group, the patients will receive EN+PN; in the low protein group, patients will be given EN alone. EN will be started in accordance with international guidelines in both groups. Efforts will be made to reach nutrition goals within 48-96 h. The efficacy of the proposed nutritional strategy will be tested as an innovative approach by functional outcomes at ICU and hospital discharge, as well as at a 6-month follow-up

Blood Levels of Macrophage Migration Inhibitory Factor after Successful Resuscitation from Cardiac Arrest

Introduction: Ischemia-reperfusion injury following cardiopulmonary resuscitation (CPR) is associated with a systemic inflammatory response, resulting in post-resuscitation disease. In the present study we investigated the response of the pleiotropic inflammatory cytokine macrophage migration inhibitory factor (MIF) to CPR in patients admitted to the hospital after out-of-hospital cardiac arrest (OHCA). To describe the magnitude of MIF release, we compared the blood levels from CPR patients with those obtained in healthy volunteers and with an aged- and gender-matched group of patient

Brief inhalation of nitric oxide increases resuscitation success and improves 7-day-survival after cardiac arrest in rats: a randomized controlled animal study

Introduction: Inhaled nitric oxide (iNO) improves outcomes when given post systemic ischemia/reperfusion injury. iNO given during cardiopulmonary resuscitation (CPR) may therefore improve return of spontaneous circulation (ROSC) rates and functional outcome after cardiac arrest (CA). Methods: Thirty male Sprague-Dawley rats were subjected to 10 minutes of CA and at least 3 minutes of CPR. Animals were randomized to receive either 0 (n = 10, Control), 20 (n = 10, 20 ppm), or 40 (n = 10, 40 ppm) ppm iNO during CPR until 30 minutes after ROSC. A neurological deficit score was assessed daily for seven days following the experiment. On day 7, brains, hearts, and blood were sampled for histological and biochemical evaluation. Results: During CPR, 20 ppm iNO significantly increased diastolic arterial pressure (Control: 57 ± 5.04 mmHg; 20 ppm: 71.57 ± 57.3 mmHg, p < 0.046) and decreased time to ROSC (Control: 842 ± 21 s; 20 ppm: 792 ± 5 s, (p = 0.02)). Thirty minutes following ROSC, 20 ppm iNO resulted in an increase in mean arterial pressure (Control: 83 ± 4 mmHg; 20 ppm: 98 ± 4 mmHg, p = 0.035), a less pronounced rise in lactate and inflammatory cytokine levels, and attenuated cardiac damage. Inhalation of NO at 20 ppm improved neurological outcomes in rats 2 to 7 days after CA and CPR. This translated into increases in 7 day survival (Control: 4; 20 ppm: 10; 40 ppm 6, (p ≤ 0.05 20 ppm vs Control and 40 ppm). Conclusions: Our study revealed that breathing NO during CPR markedly improved resuscitation success, 7-day neurological outcomes and survival in a rat model of VF-induced cardiac arrest and CPR. These results support the beneficial effects of NO inhalation after cardiac arrest and CPR

Attitudes towards treatment among patients suffering from sleep disorders. A Latin American survey

BACKGROUND: Although sleep disorders are common, they frequently remain unnoticed by the general practitioner. Few data are available about the willingness and reasons of patients with sleep disturbances to seek for medical assistance. METHODS: The results of a cross-sectional community-based multinational survey in three major Latin American urban areas, i.e. Buenos Aires, Mexico City and Sao Paulo, are reported. Two-hundred subjects suffering sleep disturbances and 100 non-sufferers were selected from the general population in each city (total number: 600 sufferers vs. 300 non-sufferers). A structured interview was conducted, sleep characteristics, feelings about sleep disturbances and strategies to cope with those problems being recorded. Data were analyzed by employing either t-test or analysis of variance (ANOVA) to the Z-transformed proportions. RESULTS: 22.7 ± 3.5 % (mean ± SEM) of subjects reported to suffer from sleep disturbances every night. About 3 out of 4 (74.2 ± 2.0 %) considered their disorder as mild and were not very concerned about it. Only 31 ± 2 % of sufferers reported to have sought for medical help. Although 45 ± 2 % of sufferers reported frequent daily sleepiness, trouble to remember things, irritability and headaches, they did not seek for medical assistance. Among those patients who saw a physician with complaints different from sleep difficulties only 1 out of 3 (33 ± 2 % of patients) were asked about quality of their sleep by the incumbent practitioner. Strategies of patients to cope with sleep problems included specific behaviors (taking a warm bath, reading or watching TV) (44 ± 1.6 %), taking herbal beverages (17 ± 1.2 %) or taking sleeping pills (10 ± 1.1 %). Benzodiazepines were consumed by 3 ± 0.6 % of sufferers. CONCLUSION: Public educational campaigns on the consequences of sleep disorders and an adequate training of physicians in sleep medicine are needed to educate both the public and the general practitioners about sleep disorders