Alterations in classical cadherins associated with progression in ulcerative and Crohn's colitis

Human colitis is a condition associated with a spectrum of altered morphologic changes and cellular adhesion. The role of cadherins, which are powerful morphoregulatory cell adhesion molecules, in colitis is provocative and as yet unknown. Herein, we present results that suggest a strong correlation between the deregulation of two cadherin molecules, E- and P-cadherins, and the progression of human colitis. We examined the expression and structural integrity of E- and P-cadherins in inflamed, dysplastic, or neoplastic human ulcerative colitis (UC) (n=58), human Crohn's colitis (n = 30), and normal tissue (n = 20) to assess cadherin function in normal and abnormal epithelium. E-cadherin is strongly expressed in normal colorectal epithelium, whereas in left-sided UC it is either down-regulated or has a single-base pair mutation in exon 4 resulting in an amino acid alteration (6 of 58 UC cases). By contrast, P-cadherin is dramatically up-regulated in both Crohn's disease and ulcerative colitis and especially in dysplastic ulcerative tissue. In vitro transfected SW-480 colorectal cells containing E-cadherin mutations identical to those in vivo were associated with increased spontaneous disaggregation compared with cells transfected with wild-type E-cadherin. Based on this evidence, we hypothesize that a small subset of colorectal cells expressing mutant E-cadherin are associated with widespread ulceration, whereas those expressing P-cadherin are associated with a rapidly dividing immature phenotype that includes dysplasia. The differential expression of mutated and wild-type cadherins examined herein are associated with a broad spectrum of abnormal epithelial phenotypes, lymphocyte integrin binding, and resistance to denudation, as is seen in the colitis adenocarcinoma sequence.     

Morphology,microstructure, and residual stress in EBPVD erbia coatings

The electron-beam physical vapor deposition of erbium-oxide coatings onto sapphire wafers is investigated to evaluate processing effects on the residual stress state and microstructure. The erbium-oxide coatings are found to be in a compressive stress state. The crystallographic texture of the erbium-oxide coating is evaluated using X-ray diffraction along with an assessment of forming the cubic erbia phase as a function of substrate temperature. In addition to the cubic erbia phase, an orthorhombic phase is found at the lower deposition temperatures. A transition is found from a two-phase erbium-oxide coating to a single phase at deposition temperatures above 948 K. The variation in morphology with deposition temperature observed in fracture cross-sections is consistent with features of the classic zone growth models for vapor-deposited oxide coatings. For high-temperature applications, a deposition process temperature above 948 K is seen to produce a stoichiometric, fully dense, and equiaxed-polycrystalline coating of cubic erbia.     

Etched carbon-fiber electrodes as amperometric detectors of catecholamine secretion from isolated biological cells

Voltammetric electrodes with micrometer dimensions have been fabricated from carbon fibers etched to a conical shape and insulated with poly(oxyphenylene) following literature procedures. The resultant electrode has a tip radius in the micron range. The response of this electrode is compared to a carbon-fiber electrode prepared by sealing a carbon-fiber electrode in a glass pipet (electrode radius greater than 3.5 microns). While the etched electrodes did not follow electrochemical theory as well as the glass-encased electrode, the etched electrode was found to be suitable for the amperometric measurement of the secretion of catecholamines from isolated bovine adrenal cells. Comparable results are only obtained when the two different electrodes are placed 1 micron from the cell surface. When the etched electrode is placed further away, less secretion is observed, because of diffusion and accompanying dilution.     

Effect of gamma-radiation and microwave heating of wheat grain on some starch properties in irradiated grain as well as in grain of the next generation crops

Grains of the Polish winter wheat variety Begra were subjected to gamma-radiation (grain harvested in 1996) within the dose range of 0.05-10 kGy and microwave heating (grain harvested in 1997) from 28 degrees C to 98 degrees C. Later the grains were divided into two parts, the first was used for direct analyses after treatment. The second part was sown on the experimental fields. The obtained crop was described as the first generation and divided into two parts. One part was destined to determination of starch properties and the second part was sown in order to obtain the second generation crop. The same pattern was conducted in order to achieve the third generation crop. gamma-Irradiation directly applied on the wheat grain reduced statistically significant falling number values and gelatinisation enthalpy (deltaH) of the grain treated by 5 and 10 kGy. Calculated linear regression correlation coefficient between the falling number values and the gelatinisation enthalpy was equal to 0.94 (p < or = 0.001) and showed that these two starch characteristics are well correlated in the case of directly irradiated wheat grain. The falling number values, peak temperatures (Tp) and gelatinisation enthalpy (deltaH), in three generations of wheat grain crop studied, did not show any statistically significant differences as a result of indirect effect of gamma-irradiation. Microwave direct heating of wheat grain to 98 degrees C caused a statistically significant increase in the falling number value and decrease in starch gelatinisation power expressed by the enthalpy of gelatinisation (deltaH). The statistically significant changes in the falling number values, slight changes in the peak temperatures (Tp) and enthalpy of gelatinisation (deltaH) were found in all three generation crops as an indirect effect of microwave heating.     

Investigation of the Associations of Novel Inflammatory Biomarkers—Systemic Inflammatory Index (SII) and Systemic Inflammatory Response Index (SIRI)—With the Severity of Coronary Artery Disease and Acute Coronary Syndrome Occurrence

Atherosclerosis, the underlying cause of coronary artery disease (CAD), has a significant inflammatory component. White blood cell count is an affordable and accessible way to assess the systemic immune response, as it comprises many subgroups with distinct and complex functions. Considering their multidirectional effect on atherosclerosis, new biomarkers integrating various leukocyte subgroups, the Systemic Inflammatory Index (SII) and the Systemic Inflammatory Response Index (SIRI), were recently devised to describe the balance between inflammation and immune reaction. This research aimed to evaluate the relationship of the intensity of inflammation measured by these biomarkers with the severity of CAD assessed with coronary angiography and with the diagnosis of acute coronary syndrome (ACS) or stable CAD in 699 patients. SIRI, but not SII, was associated with the diagnosis, having the highest values for patients with ACS (STEMI), significantly higher than in patients with stable CAD (p < 0.01). The highest SII and SIRI values were observed in patients with three-vessel CAD. SII and SIRI require further in-depth and well-designed research to evaluate their potential in a clinical setting.     

Conformational change due to esterification of hydroxy groups in erythromycin A and its major metabolite: analysis of these derivatives with different biological properties using NMR and molecular dynamics (MD) data

A conformational study is performed on the acylated erythromycin and erythralosamine derivatives from comparison between experimental results (NMR) and theoretical calculations by Molecular Dynamics (MD) in attempts to correlate their conformations with their abilities to generate cytochrome P450-nitroso metabolite complexes in vitro. As the 3'-dimethyl-amino function of the desosamine is metabolized and responsible for the interaction with cytochrome P450, its position, mobility and steric hindrance in the proximity of this functional group are related to its biological properties. The major conformations of the lactone ring were termed A (A1, A2, A3) and B (B1, B2), and this macrocycle flexibility induced five different orientations a, b, c, d and e for the desosamine sugar. Conformations A and B differ in many ways but the major change is the inward folding of the C(3) fragment in B. Conformer a exhibits an orientation of the desosamine nearly perpendicular to the macrocycle whereas the two units are in the same plane in conformations c and e. For conformation b, the cladinose unit lifts up above the macrocycle. Conformation d exhibits a turned-back cladinose. In the erythromycin derivatives esterification at the beta position to the N(CH3)2 group of the desosamine reduces the degree of freedom of the macrocyclic lactone ring which corresponds to conformation A only. The desosamine sugar was found to be perpendicular to the macrocycle (a conformer) and both sugar groups are parallel to reduce the steric energy. In the erythralosamine derivatives, the macrocycle is always present as conformation B with the two conformations b and c of the sugar rings. The steric parameters favour the b conformers in which the amino group is tilted up, while in 3,2'-dibenzoylated stacking aromatic attraction stabilizes the planar c conformer. Both isomers are thus shown to adopt well-defined conformations and to be well-adapted for a comparative structure-activity correlation studies. There is a significant relationship between the conformation b and the formation of cytochrome P450-nitroso metabolite complexes.     

Quantitative determination of catecholamines in individual bovine adrenomedullary cells by reversed-phase microcolumn liquid chromatography with electrochemical detection.

A microcolumn liquid chromatographic method for the determination of norepinephrine and epinephrine in single bovine adrenomedullary cells is described. A single cell is isolated from a culture plate, (3,4-dihydroxybenzyl)amine is added as an internal standard, and the cell is lysed with perchloric acid. After centrifugation, the supernatant is injected directly into a 42 or 50 microns Inner diameter C18 reversed-phase column operated with electrochemical detection. Detection limits for norepinephrine and epinephrine were 46 and 75 amol, respectively. Of the 22 cells examined, 8 contained predominantly norepinephrine, 10 contained predominantly epinephrine, and at least 4 cells contained significant amounts of each. On average, a single cell contained approximately 150 fmol of catecholamine.