Recently, we were fortunate to have been afforded access to post-mortem brain tissue which was part of an immunohistochemical investigation of the basal ganglia, hippocampus and cerebral cortex. In light of this access, we offer some... more
Recently, we were fortunate to have been afforded access to post-mortem brain tissue which was part of an immunohistochemical investigation of the basal ganglia, hippocampus and cerebral cortex. In light of this access,
we offer some preliminary results on the expression of parvalbumin (PV), neuropeptide-Y (NPY), calretinin (CR) and glial fibrillary acidic protein (GFAP) in the human dorsal claustrum.
Testing for the CALR mutation is included in the updated WHO criteria for essential thrombocythaemia (ET) and primary myelofibrosis (PMF). We report on the appli-cation of the CAL2 monoclonal antibody, raised against the mutated CALR gene... more
Testing for the CALR mutation is included in the updated WHO criteria for essential thrombocythaemia (ET) and primary myelofibrosis (PMF). We report on the appli-cation of the CAL2 monoclonal antibody, raised against the mutated CALR gene to myeloid cases. The immunostain was used on 116 acute myeloid leukaemias (AML) and 66 myeloproliferative neoplasms (MPN) or myelodysplastic syndromes/myelo-proliferative neoplasms (MDS/MPN). None of AML cases was stained by the CAL2 antibody, while 20/66 MPNs and MDS/MPNs appeared positive. Fourteen of the latter cases were studied by molecular techniques, and all showed aberrations of the CALR gene. In addition, CAL2 positivity was found in some small-sized elements besides megakaryocytes. By double staining, these elements corresponded to small megakaryocytes as well as both erythroid and myeloid precursors. This finding sug-gests possible occurrence of CALR gene abnormalities in a stem cell.
Background: The claustrum is present in all mammalian species. Many aspects of its morphology and function remain subject to debate. It has been suggested that calcium-binding proteins influence neuronal activity in many structures.... more
Background: The claustrum is present in all mammalian species. Many aspects of its morphology and function remain subject to debate. It has been suggested that calcium-binding proteins influence neuronal activity in many structures. Objective: The aim was to examine CR immunoreactivity in the claustrum of guinea pigs and compare it with that in other mammals. Design: CR immunoreactivity in the claustrum was analyzed in five guinea pigs using immunohistochemical techniques. The distribution of CR-positive neurons in the dorsal claustrum and endopiriform nucleus (END), and their morphological characteristics were described. Results: CR immunostaining in the dorsal claustrum and END of the guinea pig consisted of CR-positive neurons, fibers, and puncta of varying labeling density. The majority of these neurons displayed small-or medium-sized round, oval, and multipolar cell bodies with aspiny dendrites. CR-ir neurons prevailed in the periphery of both divisions. The dorsal claustrum was seen to have a weakly CR-ir central core surrounded by a rim of moderately positive neuropil. Conclusion: CR immunoreactivity in the guinea pig claustrum was not as diffuse as in higher mammals, but non-uniformity was evident. CR-ir neurons are distributed in both the dorsal claustrum and END, mostly in the periphery.
Calretinin-containing retinal amacrine cells are heterogeneous with regard to their neurochemical properties. In the rabbit retina, about 90% of them contain glycine, as evidenced in the present study by double-label immunocytochemistry.... more
Calretinin-containing retinal amacrine cells are heterogeneous with regard to their neurochemical properties. In the rabbit retina, about 90% of them contain glycine, as evidenced in the present study by double-label immunocytochemistry. In a previous report, we showed that a small population of amacrine cells contains both γ-aminobutyric acid and calretinin. In this study, we further identified this cell population by means of known secondary markers. However, none of the markers we tested (choline acetyltransferase, serotonin accumulation, NADPH-diaphorase, vasoactive intestinal polypeptide) co-localized with calretinin. A small population (1%) of the cells in the ganglion cell layer contains both calretinin and glycine. Since calretinin-positive cells in the ganglion cell layer have been identified as ganglion cells based on soma size and presence of calretinin-positive axons in the optic nerve fiber layer, this population may represent a class of ganglion cell which contains gly...
