Search results for "bioengineering"
showing 10 items of 1963 documents
Corticospinal Modulations during Motor Imagery of Concentric, Eccentric, and Isometric Actions
2019
PURPOSE It is not known yet whether the neurophysiological specificity of eccentric, concentric, and isometric contractions can also be observed when these are mentally simulated. Therefore, our aim was to assess corticospinal excitability during motor imagery (MI) of different contraction types and to test whether a passive movement during MI could have additional effects. METHODS Twelve young participants imagined contractions of the wrist flexors, firstly with the arm motionless (static mode) and second, with a congruent passive movement (wrist extension during eccentric MI and wrist flexion during concentric MI). Motor-evoked potentials (MEP) and H-reflexes were elicited in flexor carpi…
Echocardiographic reference ranges for normal non-invasive myocardial work indices: results from the EACVI NORRE study
2019
International audience; Aims - To obtain the normal ranges for 2D echocardiographic (2DE) indices of myocardial work (MW) from a large group of healthy volunteers over a wide range of ages and gender. Methods and results - A total of 226 (85 men, mean age: 45 ± 13 years) healthy subjects were enrolled at 22 collaborating institutions of the Normal Reference Ranges for Echocardiography (NORRE) study. Global work index (GWI), global constructive work (GCW), global work waste (GWW), and global work efficiency (GWE) were estimated from left ventricle (LV) pressure-strain loops. Peak LV systolic pressure was non-invasively derived from brachial artery cuff pressure. The lowest values of MW indic…
Enhanced angiogenesis in the 3D dynamic responsive implant for inguinal hernia repair ProFlor
2021
Biologic response to hernia prostheses represents a continuous source of debate. Conventional hernia meshes, in their typical static, passive configuration have been used for decades to reinforce the herniated abdominal wall. These flat implants, mainly fixated with sutures or tacks, induce poor quality fibrotic ingrowth that shrinks the mesh. In groin hernia repair, flat meshes are applied in the delicate inguinal surrounding where uncontrolled development of a scar plate can impair movement and may incorporate the sensitive nerves crossing this area. Complications deriving from mesh fixation and nerve entrapment are frequent and unpleasant for patients. To remedy these problems, a multila…
CAPD + hemoperfusion once a week in the management of children with end-stage renal disease
1983
With hemoperfusion there is a sharp decline in the solute concentration of the blood compartment, but immediately after HP the concentration of these substances rises to the original level (post-Hp rebound). It may be inferred that the result would be better and the rebound phenomenon less marked if hemoperfusion could be combined with a continuous dialysis system such as CAPD. The study was performed in 3 children of our CAPD programm. All patients were dialysed with 5 daily exchange each of one liter. The patients underwent at 2-hours hemoperfusion with a charcoal column (Gambro Adsorba 150 c) once a week. The data obtained with this form of treatment are indicative for a: significant in…
Impact of regional femoral nerve block during general anesthesia for hip arthoplasty on blood pressure, heart rate and pain control: A randomized con…
2015
Background Adequate pain management is essential for preventing hemodynamic instability which can affect the perfusion of vital organs during the perioperative period, particularly in geriatric patients. For hip arthroplasty, peripheral nerve block is frequently used, limiting the adverse effects of opioid and non-opioid analgesics. Objective The aim was to survey the impact of a supplementary single shot femoral nerve block (FNB) on hemodynamic stability and pain level. Methods After registration at German Clinical Trial Register (DRKS-ID): DRKS00000752. and Ethics Committee approval (University Hospital of Marburg), 80 patients who underwent elective hip surgery were included. Half of the…
Is It Possible to Create a “Mechanical” Arteriovenous Fistula in Hemodialysis Patients?
2010
Manual suturing still remains the best technique for the creation of vascular anastomoses on uremic patients with excellent results, despite being time consuming, difficult to perform with small vessels, and associated with a significant learning curve. We created a full mechanical arteriovenous fistula on a 65-year-old uremic patient with a new device already used in cardiac bypass surgery. The fistula was created automatically and rapidly, without the need for temporary occlusion of the artery, reducing the risk of blood clotting. We believe that mechanical devices may be useful to produce precise and fast anastomoses requiring minimal training for the surgeon.
Three dimensional reconstruction to visualize atrial fibrillation activation patterns on curved atrial geometry
2021
BackgroundThe rotational activation created by spiral waves may be a mechanism for atrial fibrillation (AF), yet it is unclear how activation patterns obtained from endocardial baskets are influenced by the 3D geometric curvature of the atrium or ‘unfolding’ into 2D maps. We develop algorithms that can visualize spiral waves and their tip locations on curved atrial geometries. We use these algorithms to quantify differences in AF maps and spiral tip locations between 3D basket reconstructions, projection onto 3D anatomical shells and unfolded 2D surfaces.MethodsWe tested our algorithms in N = 20 patients in whom AF was recorded from 64-pole baskets (Abbott, CA). Phase maps were generated by…
Enzyme-based biosilica and biocalcite: biomaterials for the future in regenerative medicine
2013
The oldest animals on Earth, sponges, form both the calcareous and the siliceous matrices of their spicules enzymatically. Until recently, it has been neglected that enzymes play crucial roles during formation of these biominerals. This paradigm shift occurred after the discovery that the enzyme silicatein, which catalyzes the polycondensation of silica, and the enzyme carbonic anhydrase (CA), which catalyzes the formation of bicarbonate (HCO3(-)/CaCO3), produce solid amorphous bioglass or biocalcite. This suggests that in mammals, biosilica and biocalcite can act anabolically during hydroxyapatite (HA) synthesis and bone formation. Biosilica and biocalcite are thus promising candidates for…
Celebrating 100 years of “polymer science”: Hermann Staudinger's 1920 manifesto
2020
The first translation into English of Hermann Staudinger's seminal 1920 paper ‘On polymerisation’, to mark its 100 year anniversary.
Marine molecular biology : An emerging field of biological sciences
2007
An appreciation of the potential applications of molecular biology is of growing importance in many areas of life sciences, including marine biology. During the past two decades, the development of sophisticated molecular technologies and instruments for biomedical research has resulted in significant advances in the biological sciences. However, the value of molecular techniques for addressing problems in marine biology has only recently begun to be cherished. It has been proven that the exploitation of molecular biological techniques will allow difficult research questions about marine organisms and ocean processes to be addressed. Marine molecular biology is a discipline, which strives t…