Oxygenator assisted dynamic microphysiological culture elucidates the impact of hypoxia on valvular interstitial cell calcification.

Introduction: Microphysiological systems (MPS) offer simulation of (patho)physiological parameters. Investigation includes items which lead to fibrosis and calcification in development and progress of calcific aortic valve disease, based e.g.

Challenges of aortic valve tissue culture - maintenance of viability and extracellular matrix in the pulsatile dynamic microphysiological system.

Background: Calcific aortic valve disease (CAVD) causes an increasing health burden in the 21 century due to aging population. The complex pathophysiology remains to be understood to develop novel prevention and treatment strategies. Microphysiological systems (MPSs), also known as organ-on-chip or lab-on-a-chip systems, proved promising in bridging in vitro and in vivo approaches by applying integer AV tissue and modelling biomechanical microenvironment.

Microphysiological Conditions Do Not Affect MDR1-Mediated Transport of Rhodamine 123 above an Artificial Proximal Tubule.

Despite disadvantages, such as high cost and their poor predictive value, animal experiments are still the state of the art for pharmaceutical substance testing. One reason for this problem is the inability of standard cell culture methods to emulate the physiological environment necessary to recapitulate in vivo processes. Microphysiological systems offer the opportunity to close this gap.

A New In Vitro Blood Flow Model for the Realistic Evaluation of Antimicrobial Surfaces.

Device-associated bloodstream infections can cause serious medical problems and cost-intensive postinfection management, defining a need for more effective antimicrobial coatings. Newly developed coatings often show reduced bacterial colonization and high hemocompatibility in established in vitro tests, but fail in animal studies or clinical trials. The poor predictive power of these models is attributed to inadequate representation of in vivo conditions.

Synthesis of -Symmetric Diphosphormonoamidites and Their Use as Ligands in Rh-Catalyzed Hydroformylation: Relationships between Activity and Hydrolysis Stability.

A series of diphosphoramidites has been synthetized with a piperazine, homopiperazine, and an acyclic 1,2-diamine unit in the backbone. New compounds were tested alongside related -acyl phosphoramidites as ligands in the Rh-catalyzed hydroformylation of -octenes to investigate their influence on the activity and regioselectivity. A subsequent study of their hydrolysis stability revealed that the most stable ligands induced the highest activity in the catalytic reaction.

Early motor evoked potentials in acute stroke: adjunctive measure to MRI for assessment of prognosis in acute stroke within 6 hours.

Background: In acute stroke, a magnetic resonance (MR) perfusion-weighted imaging (PWI) and diffusion-weighted imaging (DWI) mismatch (PWI>DWI mismatch) may indicate tissue at risk for infarction and poor prognosis. However, different to early enthusiasm about this surrogate marker, its validity has shown several drawbacks in individual patients. Rather than relying on imaging, we evaluated motor evoked potentials (MEP) as a measure of cerebral function in the acute stroke setting.

Non-oral drug delivery in Parkinson's disease: a summary from the symposium at the 7th International Congress of Parkinson's Disease and Movement Disorders. 10-14 November 2002, Miami, FL, USA.

This symposium reviewed the issues of non-oral therapy in the late stage Parkinson's disease (PD). The accepted standard treatment of PD is oral levodopa or oral dopamine agonists. However, the long-term complications and limitations of this treatment might be improved by changing therapy from the present pulsatile stimulation to a more constant stimulation of central dopamine receptors.

Acceleration of cerebral blood flow velocity in a patient with sleep apnea and intracranial arterial stenosis.

Sleep apnea (SA) syndromes of different etiologies are known to induce complications including cardiovascular diseases and stroke. However, the exact mechanisms involved in cerebral ischemia remain obscure. We measured the cerebral blood flow velocities (CBFV) by means of transcranial Doppler sonography in an 81-year-old patient who presented with an acute ischemic stroke caused by an intracranial middle cerebral artery (MCA) stenosis in the presence of SA syndrome.

Improvement in stroke quality management by an educational programme.

Time after symptom onset in ischaemic stroke has to be as short as possible to increase success of treatment. We prospectively analysed latencies from symptom onset until the start of therapy and the rate of thrombolysis in 196 patients with suspected stroke sequentially admitted to the hospital before (6 weeks prior, n = 83) and after (n = 113) initiating an educational stroke programme (EP). A total of 345 dispatchers, paramedics, and emergency staff were trained, each person for at least 2 h.