Analysis software for medical image data tends to be expensive and usable only in a restricted environment. Therefore the aim of the current project was to implement a flexible framework for medical image processing and visualization which is portable among platforms and open to different data formats including DICOM 3.0. The software was designed as a set of tools which encapsulate specialized functionality. The tools are full stand alone applications, but they are also able to present a co-operating environment within which images and other information are communicated in real time. Currently, the emphasis is on quantitative analysis of PET data by kinetic modelling. However, general viewing capabilities are included, and the design is flexible enough that other types of processing can easily be integrated by simply plugging in Java classes. The software is successfully applied to PET data quantitation in clinical research studies and even patient studies. Portability was aimed at by encoding the programs in Java. Experience shows that the implementation of such a complex and computationally demanding Java application is feasible. Although there are major portability issues to consider, configurations can be found on which the software runs stably and at a speed comparable to C code if just-in-time compilation is available.

An integrated system for performing interventional magnetic resonance angiography (MRA) with actively visualized instruments and real-time image fusion was implemented on a 1.5 T scanner. True fast imaging with steady precession (TrueFISP) imaging provided high acquisition speed paired with high signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) for the simultaneous visualization of active instruments and arterial morphology. The system enabled simultaneous image reconstruction and image postprocessing of multiple receiver channels, with subsequent image fusion display in real time. Optional interleaved image acquisition in two planes provided additional important information for biplanar instrument guidance. Various vascular interventions, including selective catheterization and subsequent selective MRA of the abdominal aorta, renal arteries, superior mesenteric artery (SMA), hepatic artery, and aortic arch, were performed on 10 pigs under MR guidance. In terms of instrument contrast, image acquisition, reconstruction, and fusion speed, the setup represents a powerful platform for performing interventional MRA procedures.

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Carbohydrates have long been known to mediate intracellular interactions, whether within one organism or between different organisms. Sialic acids (Sias) are carbohydrates that usually occupy the terminal positions in longer carbohydrate chains, which makes them common recognition targets mediating these interactions. In this review, we summarize the knowledge about animal disease-causing agents such as viruses, bacteria and protozoa (including the malaria parasite Plasmodium falciparum) in which Sias play a role in infection biology. While Sias may promote binding of, e.g., influenza viruses and SV40, they act as decoys for betacoronaviruses. The presence of two common forms of Sias, Neu5Ac and Neu5Gc, is species-specific, and in humans, the enzyme converting Neu5Ac to Neu5Gc (CMAH, CMP-Neu5Ac hydroxylase) is lost, most likely due to adaptation to pathogen regimes; we discuss the research about the influence of malaria on this trait. In addition, we present data suggesting the CMAH gene was probably present in the ancestor of animals, shedding light on its glycobiology. We predict that a better understanding of the role of Sias in disease vectors would lead to more effective clinical interventions.