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Brain volumes computed from magnetic resonance images have potential for assisting with the diagnosis of individual dementia patients, provided that they have low measurement error and high reliability. In this paper we describe and validate icobrain dm, an automatic tool that segments brain structures that are relevant for differential diagnosis of dementia, such as the hippocampi and cerebral lobes. Experiments were conducted in comparison to the widely used FreeSurfer software. The hippocampus segmentations were compared against manual segmentations, with significantly higher Dice coefficients obtained with icobrain dm (25-75th quantiles: 0.86-0.88) than with FreeSurfer (25-75th quantiles: 0.80-0.83). Other brain structures were also compared against manual delineations, with icobrain dm showing lower volumetric errors overall. Test-retest experiments show that the precision of all measurements is higher for icobrain dm than for FreeSurfer except for the parietal cortex volume. Finally, when comparing volumes obtained from Alzheimer's disease patients against age-matched healthy controls, all measures achieved high diagnostic performance levels when discriminating patients from cognitively healthy controls, with the temporal cortex volume measured by icobrain dm reaching the highest diagnostic performance level (area under the receiver operating characteristic curve = 0.99) in this dataset., Competing Interests: Declaration of Competing Interest The following authors are employed (or have been employed at the time of performing the work relevant for this paper) by icometrix: Hanne Struyfs, Diana M. Sima, Annemie Ribbens, Nuno Pedrosa de Barros, Thanh Vân Phan, Lene Claes, Maria Ines Ferraz Meyer, Wim Van Hecke, Dirk Smeets. Melissa Wittens and Ellis Niemantsverdriet have no competing interests. Sebastiaan Engelborghs has received unrestricted research grants from Janssen Pharmaceutica NV and ADx Neurosciences (paid to institution)., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

The structure of the brain is subject to very rapid developmental changes during early childhood. Pediatric studies based on Magnetic Resonance Imaging (MRI) over this age range have recently become more frequent, with the advantage of providing in vivo and non-invasive high-resolution images of the developing brain, toward understanding typical and atypical trajectories. However, it has also been demonstrated that application of currently standard MRI processing methods that have been developed with datasets from adults may not be appropriate for use with pediatric datasets. In this review, we examine the approaches currently used in MRI studies involving young children, including an overview of the rationale for new MRI processing methods that have been designed specifically for pediatric investigations. These methods are mainly related to the use of age-specific or 4D brain atlases, improved methods for quantifying and optimizing image quality, and provision for registration of developmental data obtained with longitudinal designs. The overall goal is to raise awareness of the existence of these methods and the possibilities for implementing them in developmental neuroimaging studies., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Pediatric brain volumetric analysis based on Magnetic Resonance Imaging (MRI) is of particular interest in order to understand the typical brain development and to characterize neurodevelopmental disorders at an early age. However, it has been shown that the results can be biased due to head motion, inherent to pediatric data, and due to the use of methods based on adult brain data that are not able to accurately model the anatomical disparity of pediatric brains. To overcome these issues, we proposed child metrix , a tool developed for the analysis of pediatric neuroimaging data that uses an age-specific atlas and a probabilistic model-based approach in order to segment the gray matter (GM) and white matter (WM). The tool was extensively validated on 55 scans of children between 5 and 6 years old (including 13 children with developmental dyslexia) and 10 pairs of test-retest scans of children between 6 and 8 years old and compared with two state-of-the-art methods using an adult atlas, namely ico brain (applying a probabilistic model-based segmentation) and Freesurfer (applying a surface model-based segmentation). The results obtained with child metrix showed a better reproducibility of GM and WM segmentations and a better robustness to head motion in the estimation of GM volume compared to Freesurfer. Evaluated on two subjects, child metrix showed good accuracy with 82-84% overlap with manual segmentation for both GM and WM, thereby outperforming the adult-based methods (icobrain and Freesurfer), especially for the subject with poor quality data. We also demonstrated that the adult-based methods needed double the number of subjects to detect significant morphological differences between dyslexics and typical readers. Once further developed and validated, we believe that child metrix would provide appropriate and reliable measures for the examination of children's brain.

Protein microarrays have emerged as an indispensable research tool for providing information about protein functions and interactions through high-throughput screening. Traditional methods for immobilizing biomolecules onto solid surfaces have been based on covalent and noncovalent binding, entrapment in semipermeable membranes, microencapsulation, sol gel, and hydrogel methods. Each of these techniques has its own strengths but fails to combine the most important tenets of a functional protein microarray such as covalent attachment, native protein conformation, homogeneity of the protein monolayer, control over active site orientation, and retention of protein activity. Here we present a selective and site-directed covalent immobilization technique for proteins via a benzoxazine ring formation through a Diels-Alder reaction in water and a genetically encoded 3-amino-L-tyrosine (3-NH(2)Tyr) amino acid. Fully functional protein microarrays, with monolayer arrangements and complete control over their orientations, were generated using this strategy., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Fishborne zoonotic trematodes (FZT) are endemic in humans and cultured fish in Vietnam but little is known about FZT in domestic animals. A study was designed to determine FZT prevalence and species diversity, and risk factors for infection, in dogs, cats and pigs. Faecal samples from 186 dogs, 94 cats and 168 pigs belonging to 132 households in Nghia Hung district, Nam Dinh province, were examined for small trematode eggs; those were trematode eggs with length less than 50 microm. Prevalence of FZT varied significantly between cats (70.2%), dogs (56.9%) and pigs (7.7%). Forty-nine of the egg-positive animals (25 dogs, 20 cats and 4 pigs) were necropsied to obtain adult trematodes for identification. The liver fluke, Clonorchis sinensis, and 11 species of intestinal flukes including Haplorchis, Stellantchasmus, Stictodora and Centrocestus were recovered from the infected animals. The practice of feeding raw fish to the animals was a significant risk factor for infection; this risk was reduced if the animals were periodically treated with anthelmintics. Based on the high prevalence of FZT and certain risky husbandry practices, domestic animals are likely to be major contributors of FZT eggs to the environment. Therefore, education of farmers to avoid feeding raw fish and to perform regular anthelmintic treatment of dogs, cats and pigs is needed in integrated FZT control programs.

Obesity induces a low-grade systemic chronic inflammatory condition for which macrophages are responsible. We hypothesized that obesity affects osteoclastogenesis by acting on bone marrow-derived macrophages (BMM). Male mice were fed a high-fat diet (45% of energy) or a standard diet (10% of energy) for 13 wk. We found that the density of the femurs of obese mice was significantly lower than that of the femurs of lean mice. Osteoclastogenesis was enhanced in the BMM from obese mice. Lower levels of interleukin (IL)-10 were generated by the BMM from obese mice than by those from lean mice upon stimulation of receptor activator of nuclear factor-kappaB ligand. Neutralization of IL-10 in the BMM from obese mice was not as effective in increasing osteoclast (OC) formation as that in those from lean mice. Exogenous IL-10 inhibited OC formation more strongly in the BMM from obese mice than those from lean mice. The elevated level of OC formation in the BMM from obese mice may thus be due to in part to the lower level of IL-10, a negative regulator of osteoclastogenesis. Our results suggest that obesity is associated with bone loss via enhanced osteoclastogenesis due to reduced IL-10 production by the BMM from obese mice.