S U M M A R YNeospora caninum is an Apicomplexan protozoan that has the dog as a definitive host and cattle (among other animals) as intermediate hosts. It causes encephalopathy in dogs and abortion in cows, with significant loss in worldwide livestock. As any Apicomplexan, the parasite invades the cells using proteins contained in the phylum-specific organelles, like the micronemes, rhoptries and dense granules. The aim of this study was the characterization of a homologue (denominated NcMIC2-like1) of N. caninum thrombospondin-related anonymous protein (NcMIC2), a micronemal protein previously shown to be involved in the attachment and connection with the intracellular motor responsible for the active process of invasion. A polyclonal antiserum raised against the recombinant NcMIC2-like1 functional core (thrombospondin and integrin domains) recognized the native form of NcMIC2-like1, inhibited the in vitro invasion process and localized NcMIC2-like1 at the apical complex of the parasite by confocal immunofluorescence, indicating its micronemal localization. The new molecule, NcMIC2-like1, has features that differentiates it from NcMIC2 in a substantial way to be considered a homologue †.

This paper compares structural and magnetic properties of CoFeB thin films and tunnel junction electrodes, with a boron content of 10 at % (CFB10) and 20 at % (CFB20). X-ray diffraction of 20–60 Å thick CoFeB films indicates amorphous structure in the as-deposited state, independent of the B content. The CFB10 films develop a strong (111) texture after annealing at 280 °C, while CFB20 films require annealing at 320 °C. However, films with either composition can remain amorphous upon anneal, if thinner than 40 Å. The crystallization temperature was corroborated by analysis of exchange bias and coercive fields. Tunnel junctions based on CFB10 and CFB20 were fabricated by ion beam and magnetron sputtering, respectively, and patterned down to 1×2μm2. From magnetic measurements, bottom-pinned MnIr∕CFB10 or MnIr∕CFB20 junctions have similar exchange fields upon anneal. For top-pinned structures, week exchange is obtained using CFB20∕MnIr. Synthetic antiferromagnets (CFB∕Ru∕CFB) were also studied. Antiferromagnetic coupling (AF) can be produced with 6–8 Å thick Ru spacers in glass∕CFB10∕Ru∕CFB10 multilayers, while CFB20∕Ru∕CFB20 amorphous structures are only weekly AF coupled. CFB10-based junctions can sustain annealing up to 360 °C without degradation of the magnetic properties of the CFB electrodes and ferromagnetic coupling fields (Hf), while maintaining TMR values of 30%.

Neospora caninum is an apicomplexan parasite that causes infectious abortion in cows. As an obligate intracellular parasite, N. caninum requires a host cell environment to survive and replicate. The locomotion and invasion mechanisms of apicomplexan parasites are centred on the actin-myosin system to propel the parasite forwards and into the host cell. The functions of actin, an intrinsically dynamic protein, are modulated by actin-binding proteins (ABPs). Actin-depolymerising factor (ADF) is a ubiquitous ABP responsible for accelerating actin turnover in eukaryotic cells and is one of the few known conserved ABPs from apicomplexan parasites. Apicomplexan ADFs have nonconventional properties compared with ADF/cofilins from higher eukaryotes. In the present paper, we characterised the ADF from N. caninum (NcADF) using computational and in vitro biochemical approaches to investigate its function in rabbit muscle actin dynamics. Our predicted computational tertiary structure of NcADF demonstrated a conserved structure and phylogeny with respect to other ADF/cofilins, although certain differences in filamentous actin (F-actin) binding sites were present. The activity of recombinant NcADF on heterologous actin was regulated in part by pH and the presence of inorganic phosphate. In addition, our data suggest a comparatively weak disassembly of F-actin by NcADF. Taken together, the data presented herein represent a contribution to the field towards the understanding of the role of ADF in N. caninum and a comparative analysis of ABPs in the phylum Apicomplexa.

Neospora caninum is an apicomplexan parasite strongly related to reproductive problems in cattle. The neosporosis control is not well established and several fronts are under development, predominantly based on immune protection, immunomodulation and chemotherapy. The use of anti-malarial drugs as therapeutic sources has, in theory, considerable potential for any apicomplexan. Drugs such as methylene blue (MB) and pyrimethamine (Pyr) represent therapeutic options for malaria; thus, their use for neosporosis should be assessed. In this work, we tested the effects of MB and Pyr on N. caninum proliferation and clearance, using LacZ-tagged tachyzoites. The drugs inhibited at nanomolar dosages and its combination demonstrated an antagonistic interaction in proliferation assays, according to the Chou and Talalay method for drug combination index. However, the drug combination significantly improved the parasite in vitro clearance. The repositioning of well-established drugs opens a short-term strategy to obtain low-cost therapeutics approaches against neosporosis.

The results show a reduction in bone activity, suggesting increased risk of adynamic bone and loss of bone volume. Cortical bone seems less affected by post-transplant biological changes in the first years after kidney transplantation.

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