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Today researchers look for a possibility to keep cells for a long time without losing their viability. For that cryopreservation is often used. In this process it is necessary that the cells are not destroyed so cryoprotective agents (CPA) are needed. At the moment 5 to 10 % dimethylsulfoxide (DMSO) is mostly used, but this chemical is cytotoxic to the cells. So an alternative is needed. In this work experiments are made with an icebindingprotein (IBP) of Hypogastrura harveyi, as an alternative to DMSO. It was shown in previous studies that this protein isn’t cytotoxic for the cells, with crude extract and purified inclusion bodies it even seems that the mixtures have a positive effect on growth and proliferation. As a first step the protein was produced heterologous in E. coli and then the crude extract and the purified inclusion bodies were used for experiments on the influence of the IBP on the cryopreservation of mesenchymal stem cells from the common marmoset monkey Callithrix jacchus. In the process it was found that the protein could not replace DMSO completely. But it was possible to show that the DMSO-concentration can be reduced by adding the IBP.

When intense lightwaves accelerate electrons through a solid, the emerging high-order harmonic (HH) radiation offers key insights into the material.sup.1-11. Sub-optical-cycle dynamics--such as dynamical Bloch oscillations.sup.2-5, quasiparticle collisions.sup.6,12, valley pseudospin switching.sup.13 and heating of Dirac gases.sup.10--leave fingerprints in the HH spectra of conventional solids. Topologically non-trivial matter.sup.14,15 with invariants that are robust against imperfections has been predicted to support unconventional HH generation.sup.16-20. Here we experimentally demonstrate HH generation in a three-dimensional topological insulator--bismuth telluride. The frequency of the terahertz driving field sharply discriminates between HH generation from the bulk and from the topological surface, where the unique combination of long scattering times owing to spin-momentum locking.sup.17 and the quasi-relativistic dispersion enables unusually efficient HH generation. Intriguingly, all observed orders can be continuously shifted to arbitrary non-integer multiples of the driving frequency by varying the carrier-envelope phase of the driving field--in line with quantum theory. The anomalous Berry curvature warranted by the non-trivial topology enforces meandering ballistic trajectories of the Dirac fermions, causing a hallmark polarization pattern of the HH emission. Our study provides a platform to explore topology and relativistic quantum physics in strong-field control, and could lead to non-dissipative topological electronics at infrared frequencies. High-harmonic generation from the Dirac-like surface state of a topological insulator is separated from bulk contributions and continuously tuned by the carrier-envelope phase of the driving lightwave., Author(s): C. P. Schmid [sup.1] , L. Weigl [sup.1] , P. Grössing [sup.2] , V. Junk [sup.2] , C. Gorini [sup.2] [sup.7] , S. Schlauderer [sup.1] , S. Ito [sup.3] [...]

Andreas O Doesch,1 Janika Repp,1 Nina Hofmann,1 Christian Erbel,1 Lutz Frankenstein,1 Christian A Gleissner,1 Constanze Schmidt,1 Arjang Ruhparwar,2 Christian Zugck,1 Paul Schnitzler,3 Philipp Ehlermann,1 Thomas J Dengler,4 Hugo A Katus11Department of Cardiology, 2Department of Cardiac Surgery, 3Department of Infectious Disease, Virology, University of Heidelberg, Heidelberg, 4Department of Cardiology, SLK Kliniken Heilbronn, Bad Friedrichshall, GermanyBackground: Cytomegalovirus (CMV) infection is a serious complication following heart transplantation. This study (June 2003-January 2010) retrospectively assessed the effects of oral valganciclovir prophylaxis in adult heart transplant recipients during the first year after transplantation.Methods: In patients with normal renal function, 900 mg of oral valganciclovir was administered twice daily for 14 days after heart transplant followed by 900 mg per day for following 6 months. In the event of renal insufficiency, valganciclovir was adjusted according to the manufacturer's recommendations. Antigenemia testing for pp65 antigen and simultaneous polymerase chain reaction (PCR) were used to document exposure to CMV. From 2003 to 2010, 146 patients (74.0% men) of mean age 50.7 ± 10.3 years at the time of heart transplant were included.Results: A total of 16 patients (11.0% of total, 75.0% male) had a positive pp65 and PCR result (ie, CMV infection) during the year following heart transplant; three of these patients had discontinued valganciclovir prophylaxis within the first 6 months following transplant because of leukopenia, including one patient developed CMV colitis. Two further patients developed CMV pneumonia during prophylactic valganciclovir therapy. Eight patients had positive pp65 and PCR tests in the 6–12 months after heart transplant following cessation of routine prophylaxis. One of these patients developed CMV pneumonia and another developed CMV colitis and CMV pneumonia. Thirty-seven of the 146 (25.3%) patients were CMV donor-seropositive/recipient-seronegative, and seven (18.9% of this subgroup) had a positive CMV test. In patients who were CMV donor-seropositive/recipient-seronegative, the risk of a positive CMV test (ie, CMV infection) was significantly elevated (P = 0.023).Conclusion: CMV prophylaxis with oral valganciclovir for 6 months following heart transplant is clinically feasible. In line with previous studies, CMV donor-seropositive/recipient-seronegative patients have a significantly elevated risk of CMV infection. In patients who prematurely discontinue valganciclovir, close monitoring of CMV antigenemia appears warranted. No significantly elevated rate of CMV infection was observed after 6 months of valganciclovir prophylaxis.Keywords: cytomegalovirus infection, heart transplantation, valganciclovir prophylaxis