The Natural History of Uterine Leiomyomas: Morphometric Concordance with Concepts of Interstitial Ischemia and Inanosis

Based upon our morphologic observations, we hypothesize and also provide morphometric evidence for the occurrence of progressive developmental changes in many uterine fibroids, which can be arbitrarily divided into 4 phases. These developmental phases are related to the ongoing production of extracellular collagenous matrix, which eventually exceeds the degree of angiogenesis, resulting in the progressive separation of myocytes from their blood supply and a condition of interstitial ischemia. The consequence of this process of slow ischemia with nutritional and oxygen deprivation is a progressive myocyte atrophy (or inanition), culminating in cell death, a process that we refer to as inanosis. The studies presented here provide quantitative and semiquantitative evidence to support the concept of the declining proliferative activity as the collagenous matrix increases and the microvascular density decreases

Glycan based detection and drug susceptibility of influenza virus

ABSTRACT: We have developed a panel of synthetic glycans as receptor mimics for the specific capture of influenza viruses. The glycans were printed onto commercial glass slides using a free amine at the end of a spacer to generate a small focused microarray. The microarray was evaluated for its ability to capture three different strains of influenza A virus, two H1N1, A/Brisbane/59/2007 and A/Solomon Islands/3/2006 and one H3N2, A/Aichi/2/1968. We observed an excellent detection ability with some compounds exhibiting clinically relevant (101 plaque forming units) limit of detection. We also tested the drug susceptibility of current antivirals, Zanamivir and Ostelamivir using this microarray and could determine antiviral resistance for these strains

Shiga Toxin Binding to Glycolipids and Glycans

Background: Immunologically distinct forms of Shiga toxin (Stx1 and Stx2) display different potencies and disease outcomes, likely due to differences in host cell binding. The glycolipid globotriaosylceramide (Gb3) has been reported to be the receptor for both toxins. While there is considerable data to suggest that Gb3 can bind Stx1, binding of Stx2 to Gb3 is variable. Methodology: We used isothermal titration calorimetry (ITC) and enzyme-linked immunosorbent assay (ELISA) to examine binding of Stx1 and Stx2 to various glycans, glycosphingolipids, and glycosphingolipid mixtures in the presence or absence of membrane components, phosphatidylcholine, and cholesterol. We have also assessed the ability of glycolipids mixtures to neutralize Stx-mediated inhibition of protein synthesis in Vero kidney cells. Results: By ITC, Stx1 bound both Pk (the trisaccharide on Gb3) and P (the tetrasaccharide on globotetraosylceramide, Gb4), while Stx2 did not bind to either glycan. Binding to neutral glycolipids individually and in combination was assessed by ELISA. Stx1 bound to glycolipids Gb3 and Gb4, and Gb3 mixed with other neural glycolipids, while Stx2 only bound to Gb3 mixtures. In the presence of phosphatidylcholine and cholesterol, both Stx1 and Stx2 bound well to Gb3 or Gb4 alone or mixed with other neutral glycolipids. Pre-incubation with Gb3 in the presence of phosphatidylcholine and cholesterol neutralized Stx1, but not Stx2 toxicity to Vero cells

Comparative Analysis of the Abilities of Shiga Toxins 1 and 2 To Bind to and Influence Neutrophil Apoptosis

Hemolytic-uremic syndrome (HUS), the life-threatening complication following infection by the intestinal pathogen Escherichia coli O157:H7, is due to the ability of the pathogen to produce toxins in the Shiga toxin (Stx) family. Activated neutrophils are observed in HUS patients, yet it is unclear whether Stx exerts a direct effect on neutrophils or whether the toxin acts indirectly. The effect of Stx1 and Stx2 on human neutrophils was examined. Neither Stx1 nor Stx2 altered the rate of neutrophil apoptosis. Minimal binding of either toxin to neutrophils was observed, and the toxin was easily eluted from the cells. Stx1 and Stx2 were found to circulate in the plasma of mice following intravenous injection, and both toxins were cleared rapidly from the blood. Together these results suggest that neither Stx1 nor Stx2 interacts directly with neutrophils

Intracellular Flow Cytometric Measurement of Extracellular Matrix Components in Porcine Intervertebral Disc Cells

The objective of this study was to develop and demonstrate the utility of a novel method of evaluating intracellular levels of extracellular matrix (ECM) components in intervertebral disc (IVD) cells using flow cytometry. By using this method, this study discriminated between cell populations in porcine IVD and examined the response of IVD cells to monolayer cultures, a traditional method of cell expansion, by measuring phenotypic attributes of ECM component production. It was found that monolayer cultures affected collagen production of IVD cells while there were differences in collagen type II production between the cells isolated from the annulus fibrosus (AF) and nucleus pulposus (NP) regions of IVD. Size distributions of fresh and cultured cells were also presented while the relationships between cell size and intracellular collagen level revealed heterogeneous cell populations in AF and NP regions. Furthermore, this study showed that the intracellular collagen signals of IVD cells were significantly enhanced by the treatments of Brefeldin-A and ascorbic acid. This suggests that Brefeldin-A and ascorbic acid could be used to increase the sensitivity of flow cytometric analysis on intracellular collagen levels by maximizing collagen accumulation inside cells. Since a unique feature of the flow cytometric screening tool is the ability to discriminate between various cell populations in a single sample, the flow cytometric method developed in this study may have the potential to identify specific collagen-producing cell populations from tissues or cell cultures