High pressure-low flow remodeling of the rat saphenous vein wall

Objective To better understand factors that may play a role in the development of varicosities. Methods We induced combined flow-pressure disturbance in the saphenous system of the rat by performing chronic partial clipping of the main branch. Biomechanical and quantitative histological testing was undertaken. Results A rich microvenous network developed. Bloodflow decreased to 0.65 +/- 0.18 microl/s (control side, 3.5 +/- 1.4 microl/s) and pressure elevated to 6.8 +/- 0.7 mmHg (control side, 2.3 +/- 0.2 mmHg, p < 0.05). Involution of the wall and lumen was observed (16.5%, 28.7% and 35.5% reduction in outer diameter, wall thickness and wall mass respectively, p < 0.05). Elevated macrophage (CD68) and cell division (Ki67) activity was observed. Elastic tissue and smooth muscle actin became less concentrated in the inner medial layers. Conclusions Low-flow induced morphological shrinking of the lumen in veins may override pressure-induced morphological distension. Loosening of the force-bearing elements during flow-induced wall remodeling may be an important pathological component in varicosity

Helicobacter pylori and antrum erosion-specific gene expression patterns: The discriminative role of CXCL13 and VCAM1 transcripts

BACKGROUND AND AIMS: Chronic Helicobacter pylori infection affects approximately half of the world, leads to chronic gastritis and peptic ulceration, and is linked to gastric carcinoma. Our aims were to compare the gene expression profile (GEP) of H. pylori-positive and H. pylori-negative gastric erosions and adjacent mucosa to explain the possible role and response to H. pylori infection and to get erosion-related mRNA expression patterns. METHODS: Total RNA was extracted, amplified, and biotinylated from gastric biopsies of patients with H. pylori-positive and H. pylori-negative antrum erosions (ER) (8/8) and adjacent macroscopically normal mucosae (8/8). The GEP was evaluated using HGU133plus2.0 microarrays. Two independent normalizations (MAS5.0, RMA), PAM feature selection, hierarchical cluster analysis, and discriminant analysis were done. The expression of 14 genes was also measured by real-time-polymerase chain reaction. VCAM-1 and CXCL13 immunohistochemistry (IHC) was done. RESULTS: In H. pylori infection, significant overexpression of MHC class II antigen-presenting genes, interleukin-7 receptor, ubiquitin-D, CXCR4, lactoferrin immune response-related genes, CXCL-2 and -13, CCL18 chemokine ligand, and VCAM-1 genes were established. In erosive gastritis, increased proliferation (MET) and transport (UCP2, SCFD1, KPNA4) were found, while genes associated with adhesion (SIGLEC11), transcription regulation (ESRRG), and electron and ion transport (ACADM, CLIC6) were down-regulated. Discriminant analysis successfully classified all samples into four groups (HP+ER-, HP+ER+, HP-ER+, HP-ER-) using a reduced gene set (20). Significant overexpression of VCAM-1 and CXC13 protein was detected by IHC in HP+ samples (p < .05). CONCLUSIONS: Whole genomic microarray analysis yielded new H. pylori infection and erosion-related gene expression changes. Discriminative genes can be used in mRNA-based diagnostic classification of gastric biopsies