Hierarchal Bayes model with AlexNet for characterization of M-FISH chromosome images.

The analysis of chromosomes is a significant and challenging task for clinical diagnosis and biological research. The technique based on color imaging is a multiplex fluorescent in situ hybridization (M-FISH), which was implemented to ease the exploration of the chromosomes. Thus, in this paper, we propose a novel quasi-Newton-based K-means clustering for the M-FISH image segmentation. Then, we use the expectation-maximization-based hierarchical Bayes model to characterize the M-FISH images. The contextual-based classification and region merging of chromosomal images is made to avoid any misclassification, and we made use of AlexNet, by modifying the activation functions of the sigmoid and softmax layer and for the optimum classification between the autosomal chromosomes and the sex chromosome. Finally, we conducted a performance analysis by measuring accuracy, recall, sensitivity, specificity, PPV, NPV, F-score, kappa, Jaccard, and Dice coefficient and compared with other existing methods and found that our proposed methodology can achieve more percentage of accuracy (6.96%) than the state of the art methods.

The point mutation UCH-L1 C152A protects primary neurons against cyclopentenone prostaglandin-induced cytotoxicity: implications for post-ischemic neuronal injury.

Cyclopentenone prostaglandins (CyPGs), such as 15-deoxy-Δ(12,14)-prostaglandin J2 (15dPGJ2), are reactive prostaglandin metabolites exerting a variety of biological effects. CyPGs are produced in ischemic brain and disrupt the ubiquitin-proteasome system (UPS). Ubiquitin-C-terminal hydrolase L1 (UCH-L1) is a brain-specific deubiquitinating enzyme that has been linked to neurodegenerative diseases. Using tandem mass spectrometry (MS) analyses, we found that the C152 site of UCH-L1 is adducted by CyPGs. Mutation of C152 to alanine (C152A) inhibited CyPG modification and conserved recombinant UCH-L1 protein hydrolase activity after 15dPGJ2 treatment. A knock-in (KI) mouse expressing the UCH-L1 C152A mutation was constructed with the bacterial artificial chromosome (BAC) technique. Brain expression and distribution of UCH-L1 in the KI mouse was similar to that of wild type (WT) as determined by western blotting. Primary cortical neurons derived from KI mice were resistant to 15dPGJ2 cytotoxicity compared with neurons from WT mice as detected by the WST-1 cell viability assay and caspase-3 and poly ADP ribose polymerase (PARP) cleavage. This protective effect was accompanied with significantly less ubiquitinated protein accumulation and aggregation as well as less UCH-L1 aggregation in C152A KI primary neurons after 15dPGJ2 treatment. Additionally, 15dPGJ2-induced axonal injury was also significantly attenuated in KI neurons as compared with WT. Taken together, these studies indicate that UCH-L1 function is important in hypoxic neuronal death, and the C152 site of UCH-L1 has a significant role in neuronal survival after hypoxic/ischemic injury.

Paradoxical HDL-C reduction during rosiglitazone and fibrate treatment.

AIMS: Dyslipidaemia in Type 2 diabetes mellitus (T2DM) is one of the major contributors in the pathogenesis of atherosclerosis. Thiazolidinediones (TZD), a class of drugs used in the treatment of T2DM, also modify lipids, especially lowering serum triglycerides and raising high-density lipoprotein cholesterol (HDL-C). METHODS: We describe five patients taking rosiglitazone and a fibrate who showed a paradoxical fall in HDL-C, which would have been missed if HDL-C had not been routinely monitored. This could have had a major impact in increasing the cardiovascular risk in these patients. RESULTS: Our five patients showed marked variation in both the decrease in serum HDL-C (50-89%) and also in the time taken for recovery of HDL-C after withdrawal of rosiglitazone (between 5 and 20 weeks). Apolipoprotein A1 mirrored the drop in HDL-C in four of the five patients but in one subject this was not seen, suggesting the possibility of multiple mechanisms leading to the phenomenon described, perhaps involving HDL metabolism. Improvements in glycaemic control with rosiglitazone (absolute HbA(1c) reduction between 0.6 and 3.0%) were seen in four of our patients. This suggests that the peroxisomal proliferator-activated receptor gamma signalling pathways relevant to glucose homeostasis were intact. CONCLUSION: As atherosclerosis is associated with a decrease in the HDL-C level, our observations reinforce the message that HDL-C should be measured before and after the commencement of rosiglitazone and also on increasing the dosage

Temporary disruption of the retinal basal lamina and its effect on retinal histogenesis.

An experimental paradigm was devised to remove the retinal basal lamina for defined periods of development: the basal lamina was dissolved by injecting collagenase into the vitreous of embryonic chick eyes, and its regeneration was induced by a chase with mouse laminin-1 and alpha2-macroglobulin. The laminin-1 was essential in reconstituting a new basal lamina and could not be replaced by laminin-2 or collagen IV, whereas the macroglobulin served as a collagenase inhibitor that did not directly contribute to basal lamina regeneration. The regeneration occurred within 6 h after the laminin-1 chase by forming a morphologically complete basal lamina that included all known basal lamina proteins from chick embryos, such as laminin-1, nidogen-1, collagens IV and XVIII, perlecan, and agrin. The temporary absence of the basal lamina had dramatic effects on retinal histogenesis, such as an irreversible retraction of the endfeet of the neuroepithelial cells from the vitreal surface of the retina, the formation of a disorganized ganglion cell layer with an increase in ganglion cells by 30%, and the appearance of multiple retinal ectopias. Finally, basal lamina regeneration was associated with aberrant axons failing to correctly enter the optic nerve. The present data demonstrate that a transient disruption of the basal lamina leads to dramatic and probably irreversible aberrations in the histogenesis in the developing central nervous system.