Aspartoacylase-LacZ Knockin Mice: An Engineered Model of Canavan Disease

Canavan Disease (CD) is a recessive leukodystrophy caused by loss of function mutations in the gene encoding aspartoacylase (ASPA), an oligodendrocyte-enriched enzyme that hydrolyses N-acetylaspartate (NAA) to acetate and aspartate. The neurological phenotypes of different rodent models of CD vary considerably. Here we report on a novel targeted aspa mouse mutant expressing the bacterial β-Galactosidase (lacZ) gene under the control of the aspa regulatory elements. X-Gal staining in known ASPA expression domains confirms the integrity of the modified locus in heterozygous aspa lacZ-knockin (aspalacZ/+) mice. In addition, abundant ASPA expression was detected in Schwann cells. Homozygous (aspalacZ/lacZ) mutants are ASPA-deficient, show CD-like histopathology and moderate neurological impairment with behavioural deficits that are more pronounced in aspalacZ/lacZ males than females. Non-invasive ultrahigh field proton magnetic resonance spectroscopy revealed increased levels of NAA, myo-inositol and taurine in the aspalacZ/lacZ brain. Spongy degeneration was prominent in hippocampus, thalamus, brain stem, and cerebellum, whereas white matter of optic nerve and corpus callosum was spared. Intracellular vacuolisation in astrocytes coincides with axonal swellings in cerebellum and brain stem of aspalacZ/lacZ mutants indicating that astroglia may act as an osmolyte buffer in the aspa-deficient CNS. In summary, the aspalacZ mouse is an accurate model of CD and an important tool to identify novel aspects of its complex pathology

Correlations of differentially expressed gap junction connexins cx26, cx30, cx32, cx43 and cx46 with breast cancer progression and prognosis.

BACKGROUND AND AIMS: Connexins and their cell membrane channels contribute to the control of cell proliferation and compartmental functions in breast glands and their deregulation is linked to breast carcinogenesis. Our aim was to correlate connexin expression with tumor progression and prognosis in primary breast cancers. MATERIALS AND METHODS: Meta-analysis of connexin isotype expression data of 1809 and 1899 breast cancers from the Affymetrix and Illumina array platforms, respectively, was performed. Expressed connexins were also monitored at the protein level in tissue microarrays of 127 patients equally representing all tumor grades, using immunofluorescence and multilayer, multichannel digital microscopy. Prognostic correlations were plotted in Kaplan-Meier curves and tested using the log-rank test and cox-regression analysis in univariate and multivariate models. RESULTS: The expression of GJA1/Cx43, GJA3/Cx46 and GJB2/Cx26 and, for the first time, GJA6/Cx30 and GJB1/Cx32 was revealed both in normal human mammary glands and breast carcinomas. Within their subfamilies these connexins can form homo- and heterocellular epithelial channels. In cancer, the array datasets cross-validated each other's prognostic results. In line with the significant correlations found at mRNA level, elevated Cx43 protein levels were linked with significantly improved breast cancer outcome, offering Cx43 protein detection as an independent prognostic marker stronger than vascular invasion or necrosis. As a contrary, elevated Cx30 mRNA and protein levels were associated with a reduced disease outcome offering Cx30 protein detection as an independent prognostic marker outperforming mitotic index and necrosis. Elevated versus low Cx43 protein levels allowed the stratification of grade 2 tumors into good and poor relapse free survival subgroups, respectively. Also, elevated versus low Cx30 levels stratified grade 3 patients into poor and good overall survival subgroups, respectively. CONCLUSION: Differential expression of Cx43 and Cx30 may serve as potential positive and negative prognostic markers, respectively, for a clinically relevant stratification of breast cancers

The role of histochronology in forensic practice : the Milan University legal medicine Institute experience

Introduction: the continuous improvement of the forensic evaluation techniques often includes the combined use of different methods with the purpose of obtaining proper answers to delicate topics. The classical histology together with histochemical and histochronological investigations gives a comparative evaluation of morphological and chronological data and so allowes to define the survival time and same time to demonstrate the existence of medical malpratice. Sometimes the questions made by the judge to the forensic pathologist are quite complex and difficult. for these reasons we want to give the pathologist an internationally validated tool, offering the timing of production of lesion causing the death. Material and Methods: In their laboratory work the authors took into consideration subjects died of natural and traumatic causes. In particular the authors included: subaracnoid haemorrhage (natural and post-traumatic), myocardial infarction, brain infarction, venous thromboembolism, aortic rupture and dissection, gastric and intestinal perforation and traumatic lesion of the skin. Using the classic histological method: haematoxylin-eosin and special histochemical stain, we evaluated the link between the examined lesions. In particular the histochronology: the procedure based on morphological aspects of macroscopic and microscopic findings, allowes to specify the age of the lesions with very good approximation. In our laboratory the histochronological method finds application in the medical-legal field, as routine activity, about the evaluation of the following disorders: myocardic necrosis, subaracnoid haemorrhage and pulmunary thromboembolism. The application of this histochronological method about other lesions (disorders of skin and digestive organs) represents an original and innovative technique carried-out in our laboratory from many years. About the study of rupture times of aortic and digestive organ wall it is possible to assert that the rupture has occurred in different moments. Furthermore about the skin lesions it is possible to make an evaluation of the features (ante-mortem and post-mortem) of the same lesions and, at the same time, to know the age of the onset. Results and Conclusions: the chronological interval betweern the time zero (lesion onset time) anr the time where the histological reaction appera, has been considered a classical histology limitation. So the necessity to add the histochronological study to the histological one, because the former gives the forensic pathologist the timing of the lesion examined and-at the same time-gives a decisive aid in the medical-legal practice because synthesizes on the chronological profile of the pathophysiological