A comparative study of nucleolar organizer region, proliferating cell nuclear antigen and epidermal growth factor receptor staining in colon tumours

Several studies have reported that proliferating cell nuclear antigen (PCNA), nucleolar organizer regions (NOR) and epidermal growth factor receptor (EGF-R) are cellular proliferation parameters in malignant tumours. However, the correlation of EGF-R with PCNA and NOR has not been reported in colon tumours. To clarify this, we investigated the correlation of the expression of EGF-R with PCNA and NOR in colonic epithelial tumours. Using immunohistochemical staining and one-step silver staining techniques, the expressions of EGF-R-, PCNA- and NOR-associated protein were studied in paraffin sections from five normal mucosae, 10 adenomas with mild atypia, 16 adenomas with moderate atypia, 32 adenomas with severe atypia including carcinoma in situ and 47 with invasive colon carcinomas. Significant differences were found among the respective degrees of atypia in Ag-NOR counts, PCNA labelling index (LI), and the expression of EGF-R. However, there were no significant differences among the Ag-NOR counts of the severe atypia and invasive carcinoma. There was a significant positive correlation between Ag-NOR counts and PCNA LI (P<0.001). The Ag-NOR counts and PCNA LI in EGF-R-positive cases were higher than in EGF-R-negative cases (P<0.001). These results indicate that each of the parameters increased significantly with the increase in atypia and the progression of cancer. Epidermal growth factor receptor provokes an exacerbation of protein synthesis and the cell cycle in colonic epithelial tumours.     

Unusual cutaneous manifestations of myelodysplastic syndrome

We report a 58-year-old patient with acute myeloid leukaemia who developed an oedematous erythema resembling Sweet's syndrome, accompanied by atypical erythema nodosum and bullous pyoderma gangrenosum. Examination of skin biopsies showed dense infiltration with mature neutrophils. although there was peripheral blood leucocytopenia. The oedematous erythema worsened after he was treated with granulocyte-colony-stimulating factor (G-CSF), which was given For his leucocytopenia. We suggest that when a neutrophilic dermatosis complicates leukaemia, alternatives to G-CSF should be considered for the treatment of leucocytopenia. Corticosteroids were very effective in controlling the skin lesions in our patient.     

Molecular mechanisms in the reversible regulation of morphology,proliferation and collagen metabolism in hepatic stellate cells by the three-dimensional structure of the extracellular matrix

Hepatic stellate cells (vitamin A-storing cells, lipocytes, interstitial cells, fat-storing cells, Ito cells) exist in the perisinusoidal space of the hepatic lobule and store 80% of the body's retinoids as retinyl palmitate in lipid droplets in the cytoplasm. Under physiological conditions, these cells play pivotal roles in the regulation of retinoid homeostasis; they express specific receptors for retinol-binding protein (RBP), a binding protein specific for retinol, on their cell surface, and take up the complex of retinol and RBP by receptor-mediated endocytosis. However, in pathological conditions such as liver fibrosis, these cells lose retinoids and synthesize a large amount of extracellular matrix (ECM) components including collagen, proteoglycan and adhesive glycoproteins. The morphology of these cells also changes from star-shaped stellate cells to that of fibroblasts or myofibroblasts. The three-dimensional structure of ECM components was found to regulate reversibly the morphology, proliferation and functions of hepatic stellate cells. Molecular mechanisms in the reversible regulation of stellate cells by ECM imply cell surface integrin binding to ECM components followed by signal transduction processes and then cytoskeleton assembly.     

Effect of chronic ipsapirone treatment on the density of 5-HT1A receptors and 5-HT1A receptor mRNA in discrete regions of the rat brain

Abstract There is increasing evidence that the 5-hydroxytryptamine (HT)_1A partial agonist ipsapirone is an effective anxiolytic/antidepressant agent, although its mechanism of action is not clear. In this study, we investigated the effects of chronic ipsapirone treatment (5 or 10 mg/kg; twice daily, 3 weeks) on 5-HT_1A receptor density 8-hydroxy-2-(di-n-propyl amino) tetralin (80H-DPAT) binding and the level of its mRNA ( in situ hybridization) in various regions of the rat (male Wistar 250 g) brain. Receptor density was reduced in the frontal cortex, but did not change significantly in the hippocampus and dorsal raphe nucleus. The level of receptor mRNA was unchanged in each of these brain regions. The present results suggest that the clinical anxiolytic effects of ipsapirone may be mediated partly by postsynaptic action on serotonergic transmission in the frontal cortex, but not in the hippocampus or dorsal raphe nuclei.     

The effect of changing the maxillomandibular relationship by a bite plane on the habitual mandibular opening and closing movement

The relationship between the change of afferent information from occlusal contacts and its influence on the jaw muscles was investigated. For this purpose, the following questions were posed and experimental studies designed. If the subject was given habitual occlusal contacts in centric relations with a bite plane, were the habitual mandibular closing and opening movements influenced? Second, was it easier for the subjects to accomplish regular habitual mandibular opening and closing movements, when the bite plane was inserted and removed? From the results it could be concluded that the centric occlusal contacts in centric relation were more physiological for the jaw muscles. In addition, when the new occlusal position was coincident or close to the centric relation, it was easier for the subject to study and acquire the new habitual mandibular opening and closing movement.