31 research outputs found

    A Review on Automatic Analysis of Human Embryo Microscope Images

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    Over the last 30 years the process of in vitro fertilisation (IVF) has evolved considerably, yet the efficiency of this treatment remains relatively poor. The principal challenge faced by doctors and embryologists is the identification of the embryo with the greatest potential for producing a child. Current methods of embryo viability assessment provide only a rough guide to potential. In order to improve the odds of a successful pregnancy it is typical to transfer more than one embryo to the uterus. However, this often results in multiple pregnancies (twins, triplets, etc), which are associated with significantly elevated risks of serious complications. If embryo viability could be assessed more accurately, it would be possible to transfer fewer embryos without negatively impacting IVF pregnancy rates. In order to assist with the identification of viable embryos, several scoring systems based on morphological criteria have been developed. However, these mostly rely on a subjective visual analysis. Automated assessment of morphological features offers the possibility of more accurate quantification of key embryo characteristics and elimination of inter- and intra-observer variation. In this paper, we describe the main embryo scoring systems currently in use and review related works on embryo image analysis that could lead to an automatic and precise grading of embryo quality. We summarise achievements, discuss challenges ahead, and point to some possible future directions in this research field

    B cell tolerance and antibody production to the celiac disease autoantigen transglutaminase 2

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    Autoantibodies to transglutaminase 2 (TG2) are hallmarks of celiac disease. To address B cell tolerance and autoantibody formation to TG2, we generated immunoglobulin knock-in (Ig KI) mice that express a prototypical celiac patient-derived anti-TG2 B cell receptor equally reactive to human and mouse TG2. We studied B cell development in the presence/absence of autoantigen by crossing the Ig KI mice to Tgm2 -/- mice. Autoreactive B cells in Tgm2 +/+ mice were indistinguishable from their naive counterparts in Tgm2 -/- mice with no signs of clonal deletion, receptor editing, or B cell anergy. The autoreactive B cells appeared ignorant to their antigen, and they produced autoantibodies when provided T cell help. The findings lend credence to a model of celiac disease where gluten-reactive T cells provide help to autoreactive TG2-specific B cells by involvement of gluten-TG2 complexes, and they outline a general mechanism of autoimmunity with autoantibodies being produced by ignorant B cells on provision of T cell help

    Heat treatment effect on crystalline structure and photoelectrochemical properties of anodic TiO2TiO_2 nanotube arrays formed in ethylene glycol and glycerol based electrolytes

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    The effect of annealing temperature on crystal structure of anodic titanium dioxide (ATO) layers prepared via anodization in the ethylene glycol and glycerol based electrolytes was studied. Then samples were annealed in air at the temperatures ranging from 400 to 1000 °C. The XRD measurements proved that a gradual phase change from anatase to rutile occurs with increasing annealing temperature. The anatase-to-rutile transformation occurs between 500 and 600 °C. The changes in the average crystallite sizes of anatase and rutile occurring during heat treatment of ATO layers were correlated with the mechanism of rutile phase nucleation. It was found also that the transition to the rutile phase in the samples formed in the ethylene glycol based electrolyte is considerably retarded and takes place at higher annealing temperatures due to the higher content of the embedded fluoride ions. The photoelectrochemical performance of ATO layers were studied under pulsed UV illumination. Photocurrent vs incident light wavelength and applied potential plots were recorded. The highest photocurrents were observed for the samples annealed at 400 °C, regardless of the electrolyte. It was demonstrated that the decrease in photocurrent values is related with the decreasing amount of the anatase phase in ATO samples. The enhanced photocurrent response was observed for ATO layers decorated with Ag nanoparticles. The highest photoconversion efficiencies, determined by incident photon-to-current efficiency (IPCE) calculations, were observed for the wavelength of 350 nm
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