Publications

Abstract

Abstract

PURPOSE:

Human tumors consist of heterogeneous populations of cells with distinct marker expression and functional properties. In squamous cell carcinoma of the head and neck (SCCHN), CD44 is a well-characterized marker of a resilient subpopulation of cells associated with increased tumorigenesis, radioresistance, and chemoresistance. Evidence indicates that these cells have an immune suppressive phenotype; however, mechanisms have been elusive.

EXPERIMENTAL DESIGN:

Abstract

OBJECTIVE:

Primary hyperparathyroidism is usually characterized by a monoclonal parathyroid tumor secreting excess parathyroid hormone (PTH). The main regulator of PTH secretion is calcium and the calcium-PTH set point is shifted in parathyroid tumor cells. We sought to investigate the relationship between tumor PTH and PTH mRNA expression and clinical presentation as well as regulatory factors including phosphate, vitamin D and fibroblast growth factor 23.

DESIGN:

Herpesvirus infection causes disease of variable severity in many species, including cetaceans. However, little is known about herpesvirus infection in harbor porpoises (Phocoena phocoena), despite being widespread in temperate coastal waters of the Northern Hemisphere. Therefore, we examined harbor porpoises that stranded alive in the Netherlands, Belgium, and Germany between 2000 and 2014 for herpesvirus infection and associated disease. Porpoises that died or had to be euthanized were autopsied, and samples were collected for virological and pathological analyses.

The mechanism coupling bone resorption and formation is a burning question that remains incompletely answered through the current investigations on osteoclasts and osteoblasts. An attractive hypothesis is that the reversal cells are likely mediators of this coupling. Their nature is a big matter of debate. The present study performed on human cancellous bone is the first one combining in situ hybridization and immunohistochemistry to demonstrate their osteoblastic nature.

Absorptive and secretory cells of the small intestine are derived from a single population of Lgr5-expressing stem cells. While key genetic pathways required for differentiation into specific lineages have been defined, epigenetic programs contributing to this process remain poorly characterized. Members of the BET family of chromatin adaptors contain tandem bromodomains that mediate binding to acetylated lysines on target proteins to regulate gene expression.

AIMS:
Recent attempts to study MYC distribution in human samples have been confounded by a lack of agreement in immunohistochemical staining between antibodies targeting the N-terminal or C-terminal of the MYC protein. This aim of this study was to use a novel in situ hybridisation (ISH) approach to detect MYC mRNA in clinically relevant samples, and thereby determine the reliability of MYC targeting antibodies.

We have recently reported the expression of functional cannabinoid CB2 receptors (CB2 Rs) in midbrain dopamine (DA) neurons in mice. However, little is known whether CB2 Rs are similarly expressed in rat brain because significant species differences in CB2 R structures and expression are found. In situ hybridization and immunohistochemical assays detected CB2 gene and receptors in DA neurons of the ventral tegmental area (VTA), which was up-regulated in cocaine self-administration rats.

Central leptin action is sufficient to restore euglycemia in insulinopenic type 1 diabetes (T1D); however, the underlying mechanism remains poorly understood. To examine the role of intracellular STAT3 pathways, we used LepRs/s mice with disrupted leptin-pSTAT3 signaling to test the effect of central leptin on euglycemia restoration. These mice developed STZ-induced T1D, which was surprisingly not associated with hyperglucagonemia, a typical manifestation in T1D.

Previous investigations have indicated that RNAs are mostly present in the minor population of the youngest platelets, whereas translation in platelets could be biologically important. To attempt to solve this paradox, we studied changes in the RNA content of reticulated platelets, i.e., young cells brightly stained by thiazole orange (TObright), a fluorescent probe for RNAs. We provoked in mice strong thrombocytopenia followed by dramatic thrombocytosis characterized by a short period with a vast majority of reticulated platelets.