Knockdown of swine leukocyte antigen expression in porcine lung transplants enables graft survival without immunosuppression.

Immune rejection remains the major obstacle to long-term survival of allogeneic lung transplants. The expression of major histocompatibility complex molecules and minor histocompatibility antigens triggers allogeneic immune responses that can lead to allograft rejection. Transplant outcomes therefore depend on long-term immunosuppression, which is associated with severe side effects.

Oxygen carriers affect kidney immunogenicity during machine perfusion.

Normothermic machine perfusion provides a powerful tool to improve donor kidney preservation and a route for the delivery of pharmacological or gene therapeutic interventions prior to transplantation. However, perfusion at normothermic temperatures requires adequate tissue oxygenation to meet the physiological metabolic demand. For this purpose, the addition of appropriate oxygen carriers (OCs) to the perfusion solution is essential to ensure a sufficient oxygen supply and reduce the risk for tissue injury due to hypoxia.

Heart immunoengineering by lentiviral vector-mediated genetic modification during normothermic perfusion.

Heart transplantation is associated with major hurdles, including the limited number of available organs for transplantation, the risk of rejection due to genetic discrepancies, and the burden of immunosuppression. In this study, we demonstrated the feasibility of permanent genetic engineering of the heart during perfusion. Lentiviral vectors encoding for short hairpin RNAs targeting beta2-microglobulin (shβ2m) and class II transactivator (shCIITA) were delivered to the graft during two hours of normothermic EVHP.

Human PD-L1 overexpression decreases xenogeneic human T-cell immune responses towards porcine kidneys.

Xenotransplantation offers a promising alternative to circumvent the lack of donated human organs available for transplantation. Different attempts to improve the survival of xenografts led to the generation of transgenic pigs expressing various combinations of human protective genes or knocked out for specific antigens. Currently, testing the efficiency of porcine organs carrying different genetic modifications in preventing xenogeneic immune responses completely relies on assays, humanized mouse models, or non-human primate transplantation models.

Genetic Modification of Limbs Using Machine Perfusion.

Genetic engineering is a promising tool to repair genetic disorders, improve graft function, or reduce immune responses toward allografts. organ perfusion systems have the potential to mitigate ischemic-reperfusion injury, prolong preservation time, or even rescue organ function. We aim at combining both technologies to develop a modular platform allowing the genetic modification of vascularized composite (VC) allografts.

Notes on Rayleigh's hypothesis and the extended boundary condition method.

Regarding wave scattering on a three-dimensional nonspherical obstacle, the Rayleigh hypothesis states that the scattered field can be expanded everywhere outside the obstacle using only outgoing eigensolutions of the underlying Helmholtz equation. However, the correctness of this assumption has not yet been finally clarified, although it is important for the near-field analysis of scattering processes and for multiple scattering. To circumvent this uncertainty, Waterman introduced the extended boundary condition to develop his T-matrix method.

Convergence of the iterative T-matrix method.

Among the various methods for computing the T-matrix in electromagnetic and acoustic scattering problems is an iterative approach that has been shown to be particularly suited for particles with small-scale surface roughness. This method is based on an implicit T-matrix equation. However, the convergence properties of this method are not well understood.

A numerical study of acoustic scattering by Janus spheres.

Recently Janus particles have become important in several technological fields because they have interesting properties compared with homogeneous particles. The interaction of Janus particles with sound waves is of particular interest for diagnostic purposes, and also in applications in micro- and nanotechnology. In this paper the authors demonstrate that a method of fundamental solution combined with a T-matrix that is computed from far-field information can be applied with benefit to analyse the scattering of sound waves by a particular type of Janus sphere.

Genetic Deficiency of the Histamine H-Receptor Reduces Experimental Colorectal Carcinogenesis in Mice.

Colorectal cancer (CRC), a severe complication of inflammatory bowel diseases, is a common type of cancer and accounts for high mortality. CRC can be modeled in mice by application of the tumor promoter, azoxymethane (AOM), in combination with dextran sodium sulfate (DSS), which are able to induce colitis-like manifestations. Active colitis correlates with high mucosal concentrations of histamine, which, together with the histamine receptor subtype 4 (HR), provide a pro-inflammatory function in a mouse colitis model.

Genetic Engineering of the Kidney to Permanently Silence MHC Transcripts During Organ Perfusion.

Organ gene therapy represents a promising tool to correct diseases or improve graft survival after transplantation. Polymorphic variation of the major histocompatibility complex (MHC) antigens remains a major obstacle to long-term graft survival after transplantation. Previously, we demonstrated that MHC-silenced cells are protected against allogeneic immune responses.

Modeling optical properties of particles with small-scale surface roughness: combination of group theory with a perturbation approach.

A T-matrix method for scattering by particles with small-scale surface roughness is presented. The method combines group theory with a perturbation expansion approach. Group theory is found to reduce CPU-time by 4-6 orders of magnitude.

Case study about the accuracy behavior of three different T-matrix methods.

In this paper we discuss the influence of two different sets of weighting functions on the accuracy behavior of T-matrix calculations for scalar scattering problems. The first set of weighting functions is related to one of Waterman's original approaches. The other set results into a least-squares scheme for the transmission problem.

Scattering database for spheroidal particles.

We present a database containing light scattering quantities of randomly oriented dielectric spheroidal particles in the resonance region. The database has been generated by using a thoroughly tested T-matrix method implementation. The data possess a defined accuracy so that they can be used as benchmarks for electromagnetic and light scattering computations of spheroids.

[Virtual colonoscopy--and then? Relevance of small colorectal polyps].

Unlabelled: Colorectal carcinomas are the second most frequent malignant tumors in Germany and originate predominantly from benign polyps (adenoma-carcinoma sequence). Optical colonoscopy is still the gold standard for diagnosis and treatment colorectal polyps. However, CT colonography ("virtual colonoscopy") provides an alternative procedure with similar diagnostic performance but without the possibility of endoscopic polypectomy.

Influence of passive humidification on nasal conditioning.

Background: Passive humidifiers (PH) have been beneficial to upper and lower airway humidity, especially in patients who are in a long-time ventilated intensive care unit. The goal of this pilot study was to provide nasal conditioning data and measure the benefit of a nasal PH to spontaneously breathing, conscious subjects.

Methods: Eleven healthy volunteers had to wear a PH for 1 hour, which was introduced into both nasal vestibules.

Light scattering on Chebyshev particles of higher order.

We present what we believe to be the first results of a light-scattering analysis on several Chebyshev particles characterized by higher orders. Chebyshev particles of comparatively lower orders were used in the past to study the effects of nonspherical but concave geometries in remote sensing applications. We will show that, based on the developed methodology, accurate results can also be obtained for particles of higher orders exhibiting a more pronounced surface waviness.

[Secondarily accelerated foreign bodies as a source of danger from airbag deployment].

Background: The use of airbag systems in motor vehicle construction has led to a significant reduction in both the frequency and intensity of injuries during traffic accidents. However, recent reports have shown numerous cases in which it is assumed that the airbag was the major cause of serious injury.

Case Report: In a collision with a wild boar, both airbags in the automobile deployed.

Two software tools for plane-wave scattering on nonspherical particles in the German Aerospace Center's Virtual Laboratory.

We present the methodological background, the range of applicability, and the on-line usage of two software packages, MIESCHKA and CYL, which we have developed for light-scattering analysis on nonspherical particles. MIESCHKA solves Maxwell's equations in a rigorous way but is restricted to axisymmetric geometries, whereas CYL is an approximation for finite columns with nonspherical cross sections. We have established an easy on-line access to both of these programs through the Virtual Laboratory.

[Alternating electric heart axis in a patient with small cell lung cancer].

History And Admission Findings: A 62-year-old man was admitted because of recurrent abdominal pain 18 months after small cell lung cancer (SCLC) had been diagnosed and remission achieved with chemotherapy and radiotherapy. The abdomen was soft on palpation, but pressure on the epigastric region was painful. Symptomatic treatment brought improvement, but 16 hours after admission the patient complained of severe diffuse abdominal pain.

Assessment of regional myocardial hypoperfusion with myocardial contrast echocardiography using intravenous bolus application in patients with acute chest pain: a double case report.

Myocardial contrast echocardiography using power Doppler harmonic imaging is able to document myocardial hypoperfusion. Two case reports demonstrate the potential of intravenous bolus application of microbubbles in patients with acute chest pain due to myocardial ischaemia to detect regional low flow conditions. The case reports will focus on the necessity to present Doppler intensity kinetics by Doppler intensity vs time plots or coloured M-modes to present the data more objectively.

3-D reconstruction of the vestibular endorgans in pediatric temporal bones.

We investigated the vestibular endorgans in three children using 3-D reconstructions from histological sections. The right temporal bone of a newborn child without peripheral vestibular pathology was used as reference model and the temporal bones from a child with Goldenhar syndrome and a child with Pierre Robin sequence with known peripheral vestibular pathology were studied. All five temporal bones were prepared by the celloidin technique and sectioned at 20 microm.

Myocardial contrast echocardiography for assessment of myocardial perfusion at rest in a patient with left main coronary artery stenosis.

The present case will focus on the potential of hypoperfusion detection with myocardial contrast echocardiography (MCE) using power Doppler harmonic imaging (PDHI). PDHI is normally performed in a triggered mode. Microbubbles were destroyed by the ultrasound energy in the myocardium, and myocardium has to be refilled with microbubbles within the time interval between the ultrasound pulses to obtain repetitive information about perfusion.

Intravenous myocardial contrast echocardiography during angioplasty.

Myocardial contrast echocardiography (MCE) using power Doppler harmonic imaging (PDHI) has been reported to document regional myocardial perfusion. Two case reports demonstrate the potential of intravenous myocardial contrast echocardiography during angioplasty.

Network of characterizing functions for stationary populations.

A variety of open systems in nature and society exist under dynamic equilibrium, maintained by statistical counterbalance between the entering and leaving of individuals and the stationarity of the exchange processes. A network of functions characterizing the dynamics of such a stationary population is established and discussed, which allows the mutual transference of system properties without the need of any explicit information about the microdynamic processes. In order to illustrate the potential benefit of these interdependence relations, examples taken from diverse branches of research (adsorption and reaction kinetics, demographic analysis, and coronary blood flow diagnosis) are given.