[Foundations for the scientific use of extensive health care data in Germany-results of the Data Sharing working group of the Medical Informatics Initiative]

Healthcare data are an important resource in applied medical research. They are available multicentrically. However, it remains a challenge to enable standardized data exchange processes between federal states and their individual laws and regulations. The Medical Informatics Initiative (MII) was founded in 2016 to implement processes that enable cross-clinic access to healthcare data in Germany. Several working groups (WGs) have been set up to coordinate standardized data structures (WG Interoperability), patient information and declarations of consent (WG Consent), and regulations on data exchange (WG Data Sharing). Here we present the most important results of the Data Sharing working group, which include agreed terms of use, legal regulations, and data access processes. They are already being implemented by the established Data Integration Centers (DIZ) and Use and Access Committees (UACs). We describe the services that are necessary to provide researchers with standardized data access. They are implemented with the Research Data Portal for Health, among others. Since the pilot phase, the processes of 385 active researchers have been used on this basis, which, as of April 2024, has resulted in 19 registered projects and 31 submitted research applications.

Towards a National Portal for Medical Research Data (FDPG): Vision, Status, and Lessons Learned

Harmonizing medical data sharing frameworks is challenging. Data collection and formats follow local solutions in individual hospitals; thus, interoperability is not guaranteed. The German Medical Informatics Initiative (MII) aims to provide a Germany-wide, federated, large-scale data sharing network. In the last five years, numerous efforts have been successfully completed to implement the regulatory framework and software components for securely interacting with decentralized and centralized data sharing processes. 31 German university hospitals have today established local data integration centers that are connected to the central German Portal for Medical Research Data (FDPG). Here, we present milestones and associated major achievements of various MII working groups and subprojects which led to the current status. Further, we describe major obstacles and the lessons learned during its routine application in the last six months.

HemoMIPs-Automated analysis and result reporting pipeline for targeted sequencing data

Targeted sequencing of genomic regions is a cost- and time-efficient approach for screening patient cohorts. We present a fast and efficient workflow to analyze highly imbalanced, targeted next-generation sequencing data generated using molecular inversion probe (MIP) capture. Our Snakemake pipeline performs sample demultiplexing, overlap paired-end merging, alignment, MIP-arm trimming, variant calling, coverage analysis and report generation. Further, we support the analysis of probes specifically designed to capture certain structural variants and can assign sex using Y-chromosome-unique probes. In a user-friendly HTML report, we summarize all these results including covered, incomplete or missing regions, called variants and their predicted effects. We developed and tested our pipeline using the hemophilia A & B MIP design from the “My Life, Our Future” initiative. HemoMIPs is available as an open-source tool on GitHub at: https://github.com/kircherlab/hemoMIPs

Next generation sequencing techniques enable researchers to identify causal variants for patients in large cohorts. Targeted sequencing approaches capture genomic regions of interest to allow high throughput and cost efficient patient-specific data generation. HemoMIPs is an open-source software that analyses targeted sequencing datasets generated using molecular inversion probes (MIPs) and provides HTML reports of pathogenic and benign variants, patient sex, existence of known structural variants as well as performance statistics on the sequencing run.

Signatures of Long-Term Balancing Selection in Human Genomes

Balancing selection maintains advantageous diversity in populations through various mechanisms. Although extensively explored from a theoretical perspective, an empirical understanding of its prevalence and targets lags behind our knowledge of positive selection. Here, we describe the Non-central Deviation (NCD), a simple yet powerful statistic to detect long-term balancing selection (LTBS) that quantifies how close frequencies are to expectations under LTBS, and provides the basis for a neutrality test. NCD can be applied to a single locus or genomic data, and can be implemented considering only polymorphisms (NCD1) or also considering fixed differences with respect to an outgroup (NCD2) species. Incorporating fixed differences improves power, and NCD2 has higher power to detect LTBS in humans under different frequencies of the balanced allele(s) than other available methods. Applied to genome-wide data from African and European human populations, in both cases using chimpanzee as an outgroup, NCD2 shows that, albeit not prevalent, LTBS affects a sizable portion of the genome: ∼0.6% of analyzed genomic windows and 0.8% of analyzed positions. Significant windows (P < 0.0001) contain 1.6% of SNPs in the genome, which disproportionally fall within exons and change protein sequence, but are not enriched in putatively regulatory sites. These windows overlap ∼8% of the protein-coding genes, and these have larger number of transcripts than expected by chance even after controlling for gene length. Our catalog includes known targets of LTBS but a majority of them (90%) are novel. As expected, immune-related genes are among those with the strongest signatures, although most candidates are involved in other biological functions, suggesting that LTBS potentially influences diverse human phenotypes.

Two-time quantum transport and quantum diffusion

Based on the nonequilibrium Green's function technique, a unified theory is developed that covers quantum transport and quantum diffusion in bulk semiconductors on the same footing. This approach, which is applicable to transport via extended and localized states, extends previous semiphenomenological studies and puts them on a firm microscopic basis. The approach is sufficiently general and applies not only to well-studied quantum-transport problems, but also to models, in which the Hamiltonian does not commute with the dipole operator. It is shown that even for the unified treatment of quantum transport and quantum diffusion in homogeneous systems, all quasimomenta of the carrier distribution function are present and fulfill their specific function. Particular emphasis is put on the double-time nature of quantum kinetics. To demonstrate the existence of robust macroscopic transport effects that have a true double-time character, a phononless steady-state current is identified that appears only beyond the generalized Kadanoff-Baym ansatz.

Influence of an electric field on the spin polarization in semiconductor superlattices

The influence of a quantizing electric field on the spin polarization is treated for semiconductor superlattices with a Rashba spin-orbit interaction. For weakly coupled superlattices, the quantum kinetic equation for the canonically transformed density matrix is analytically solved. The spin polarization, which is induced by a magnetic field via the Zeeman splitting, exhibits a sharp minimum at the cyclotron-Stark tunnelling resonance. This electric-field-induced resonant tunnelling mixes different spin states and leads to a strong spin depolarization.

Filter paper cards contaminated with EMLA cream produce artefacts on acylcarnitine analysis

Electrospray ionization tandem mass spectrometry is a widely applied method for the analysis of acylcarnitines in blood samples spotted on filter paper cards (Guthrie cards). When the filter paper cards are contaminated by EMLA cream, highly intense signals at m/z 221 and 235 are detected under ESI-MS/MS conditions, monitoring for precursors of m/z 85. These signals correspond to the active ingredients prilocaine and lidocaine in EMLA and overlap with the signals from the isotopically labelled internal standards (2H3)propionyl carnitine and (2H3)butyrylcarnitine. This interference prevents the proper quantification of the two short-chain acylcarnitines when samples are analysed without derivatization.

Comparison of combined and separated biological aerated filter (BAF) performance for pre-denitrification/nitrification of municipal wastewater

The performance of two systems of semi-industrial up-flow biological aerated filters (BAF) with pre-denitrification followed by nitrification was studied and compared under various operating and loading conditions. The first system consisted of two separate reactors for the denitrification and the nitrification step, whereas in the second system the aerobic nitrification zone was packed on top of the anoxic denitrification zone in one reactor. The second system potentially offers substantial savings in investment costs and space requirements for a large scale treatment plant. Regarding the elimination of carbonaceous pollution and denitrification the systems did not show significant differences. However, nitrification in the combined system suffered from the mixing of different biocenosis by daily backwashing and was reduced to 50-70% of the separated system's performance. Factors such as oxygen concentration, raw water composition and loading rates affected both systems' nitrification rates in similar ways. Since it is impossible to optimise the nitrification and denitrification processes separately, the combined system should only be considered for large scale applications if space is very scarce and if a stable raw water composition can be expected. If strict limit values for nitrate have to be met in the effluent, a combination of pre- and post-denitrification is advantageous and advisable.

Platelet Survival in Healthy Volunteers After Storage with N-(2-mercaptopropionyl)-glycine

The sulphhydryl group containing drug N-(2-mercaptopropionyl)-glycine (MPG) was tested as a cytoprotective substance for storage of human platelets for transfusion. Autologous platelets stored for 48 h at 21 ± 1°C in the absence (control-platelets) or in the presence (MPG-platelets) of MPG, respectively, were labelled with Indium-III oxine and retransfused into the healthy donors. Significantly higher survival and a higher spleen/liver-ratio were obtained using stored MPG-platelets compared to stored control-platelets. Additionally, a very strong correlation was found between the percentage of discocytes counted after incubation of stored platelets in fresh plasma in vitro and the survival of stored platelets after retransfusion in vivo.

99mTc-labelling of leucocytes with 99mTc-DPO: a complex developed for myocardial imaging

The lipophilic 99mTc-DPO complex, developed as a myocardial imaging radiopharmaceutical, was used to label leucocytes. After an incubation of 0.1 ml 99mTc-DPO (8 micrograms DMPE*2HCl) with mixed leucocytes in plasma, the labelling efficiency was over 70%. During incubation in 5 ml plasma, a loss of activity was found between 20% (1 h) and 35% (3 h) caused by elution. Disturbances of cell viability could not be found with the help of the chemiluminescence test. The in vivo recovery was determined in three dogs and was 45%-50% (0.5 h), 30%-36% (1 h), and 18%-24% (3 h). Autologous 99mTc-DPO-leucocytes were used on seven patients with suspected osteomyelitis, there were four true negative and three true positive results. The target/nontarget ratio determined by ROI in the positive cases was 1.8 to 2.5 at 3 h after injection.

[111Indium-thrombocyte scintigraphy and percutaneous transluminal dilatation (angioplasty) of supra-aortic vascular stenoses. A new method for deciding therapy and for follow-up control]

Scintigraphy with 111indium-marked autologous platelets has been used during percutaneous transluminal dilatation of supra-aortic arterial stenoses; there were 14 successful dilatations and one attempted dilatation. The material consisted of nine stenoses of the internal carotid artery, two stenoses at the origin of the vertebral artery and four stenoses of the first part of the left subclavian artery. Deposition of thrombi could be demonstrated by scintigraphy, both before and after catheter dilatation. The value of this method for deciding on the type of treatment and for observing the course of percutaneous dilatation of cerebral vessels is discussed.

[Venography with 111Indium-labelled autologous thrombocytes]

111Indium-labelled thrombocytes were used for radionuclide venography in ten patients. All types of thrombi could be demonstrated with a high degree of accuracy, particularly if the marked thrombocytes were injected distally. In cases of complete occlusion by thrombus, the peripheral end of the clot appeared as a 'hot spot'. Non-occluding thrombi with a thrombogenic surface can be differentiated from lesions of the endothelium. Compared with venography using labelled microspheres, labelled thrombocytes have the advantage of demonstrating the degree of activity of the thrombotic process.

[Blood loss in dialysis in repeatedly used capillary dialysators]

The blood losses increase to the twofold to threefold by capillary dialysators C-DAK 4 and C-DAK 5 are about 6.8 ml and 26 ml, respectively, in the first use. In repeated use of the C-DAK 4 the blood losses by the C-DAK 5, however, are so high that it is not to be advised to use them manifold under our conditions of dialysis. By an increase of the reperfusion quantity from 150 to 250 ml of electrolyte solution for one C-DAK 4 blood losses may considerably be reduced. In a parallel switching of two C-DAK 4 each exemplar should be perfused individually.

[A modified method for labeling erythrocytes with 99mTc (author's transl)]

A modified method for labeling erythrocytes with 99mTc-sodium pertechnetate for spleenic scintigraphy is described. In vitro investigations have shown that by omitting the customary process of washing and by simultaneous alteration of the erythrocytes during the tin incubation period, the duration of erythrocyte labeling can be considerably reduced. A yield of 96 of 98% can be achieved. The effect of the tin on the erythrocytes is further investigated. The effect of the incubation period and temperature, of the plasma in the erythrocyte suspension, of stirring and agitation, of the dispersion liquid and tin concentration were studied. The method proves satisfactory in 56 controlled spleenic scintigrams.