Motohide Takahama

Detection of c-Ki-ras gene mutation in paraffin sections of adenocarcinoma and atypical bronchioloalveolar cell hyperplasia of human lung

DNA of minute specimens taken from formalin-fixed and paraffin-embedded tissue was used as a template for the polymerase chain reaction (PCR) to examine whether the c-Ki-ras gene is activated in atypical bronchioloalveolar cell hyperplasia (ABH) of human lung. The c-Ki-ras gene was successfully amplified on 131 samples from 29 cases of lung adenocarcinoma (87.3% of all samples used as templates) by the nested PCR method. Point mutations at codon 12 of the c-Ki-ras gene could be detected in carcinoma tissue of 6 cases (20.7% of all cases), also detected in ABHs showing moderate to severe atypia of 2 cases. PCR amplification is a useful technique for studying pin-point pathological lesions in a routine paraffin section at the molecular level.

Metal concentrations in lung tissue of subjects suffering from lung cancer.

SummaryConcentrations of nine metals (Fe, Ca, Mg, Zn, Cu, Co, Ni, Pb and Cr) concentrations in lung tissues from 224 lung cancer cases were compared with those in other cases to achieve an understanding of their contribution to the development of lung cancer and the varieties after the development of cancer. Comparisons of metal concentrations in each cell type of lung cancer were also performed. All cases were collected from routine autopsies in Tokyo and Saitama, Japan. The copper concentration in tissue from lung cancers was significantly higher than that in other specimens, although calcium, magnesium, zinc and cobalt concentrations in lung cancers were significantly lower than those in other cases. There were no significant differences in the 99% intervals (excluding extremely high values for occupationally exposed cases) for chromium, nickel and lead concentrations between lung cancers and other cases, although these values were lower in lung cancers. However, in comparisons of men only, the chromium concentration, the degree of lung contamination and the severity of pulmonary emphysema in lung cancer cases were significantly higher than those in other specimens. Moreover, percentages of lung cancer in men at each degree of contamination and each severity of emphysema increased with increasing grades. Thus, this finding could be evidence that the exposure to contaminants other than chromium and nickel in the air had affected the development of lung cancer, except for occupationally exposed individuals. Therefore, almost all chromium and nickel in lung tissue might not deposit in carcinogenic forms such as hexavalent chromium or nickel subsulfide. Comparison of the characteristics in each cell type of lung cancer revealed that calcium and chromium concentrations in lung tissue (not including tumor) or squamous cell carcinomas were higher than those in the other cell types. In small cell carcinomas, calcium magnesium and zinc concentrations were low.

Systemic granulomatous arteritis associated with Epstein-Barr virus infection.

Abstract A 61-year-old woman initially presented with symptoms and findings reminiscent of infectious mononucleosis, and her illness then took a rapidly fatal course. Autopsy revealed widespread granulomatous arteritis, with multinucleated giant cells but without eosinophils and fibrinoid necrosis, affecting small arteries and arterioles and infiltration of haemophagocytic histiocytes into many organs. In situ hybridization with Epstein-Barr virus (EBV)-specific oligonucleotide probes showed positive signals in the infiltrating immune cells and epithelial and endothelial cells of the affected organs. EBV-associated haemophagocytic syndrome (EBV-AHS) with systemic granulomatous arteritis was diagnosed. From the immunophenotypes of the infiltrating immune cells, a possible role of CD4+ T-cells in the pathogenesis of this haemophagocytic syndrome and granulomatous vasculitis was suggested.

Detection of c-Ki-ras oncogene mutation in gastric adenomas with formalin-fixed, paraffin-embedded biopsy materials

Point mutations at codon 12 of the c-Ki-ras gene were investigated in 103 biopsy tissues from 38 patients with gastric adenoma. DNA from minute specimens of formalin-fixed paraffin-embedded tissue was amplified by nested polymerase chain reaction (PCR) and the restriction fragment length polymorphism (RFLP) method was used to detect mutations of the c-Ki-ras gene. Mutations were detected in 4 of the 38 gastric adenomas (10.5%), but were not detected in intestinal metaplasias and gastric adenocarcinomas. Of the 4 mutation-positive gastric adenomas, the GGT sequence in codon 12 changed to GAT in 2 cases, to GTT in 1 case and to TGT in 1 case. We classified gastric adenomas into three degrees of atypia; mutations were detected only in biopsy tissues with moderate and severe atypia but were not detected in biopsy tissues with mild atypia. When different biopsy tissues from a mutation-positive gastric adenoma were examined, the mutation was not always detected in every tissue sample examined. This suggests that mutations are not homogeneously distributed, even in the same adenoma. It is possible to follow up the mutation of biopsy materials of gastric adenoma by this method.

Effects of uranium ore dust on cultured human lung cells.

Effects of uranium ore dust on cell proliferation, lipid peroxidation and micronuclei formation were compared with silica (DQ12) and titanium oxide in normal human distal airway epithelial cells (NHDE), human lung cancer cells (A549) and human lung fibroblast cells. Cell proliferation was significantly inhibited with uranium ore dust and silica but not with titanium oxide. Lipid peroxidation was significantly enhanced only with uranium ore dust. Micronuclei formation was significantly stimulated with uranium ore dust in A549 and NHDE cells, but not in fibroblast cells. Silica stimulated micronuclei formation only in A549 cells. The results showed the outstanding effect of uranium ore dust on lipid peroxidation and micronuclei formation in human lung cells compared to silica and titanium dioxide.

Phenotypic change of muscularis mucosae in early invasive colorectal adenocarcinoma

Background—Invasive colorectal adenocarcinomas have bundles of eosinophilic spindle cells, which are regarded as myofibroblasts, in their desmoplastic stroma, some of which are continuous with the muscularis mucosa. Aim—To investigate the relation between the eosinophilic spindle cells and the muscularis mucosa based on their cytoskeletal phenotypes in early invasive colorectal adenocarcinoma. Methods—Formalin fixed, paraffin wax embedded tissues of 17 early invasive colorectal adenocarcinomas were immunostained for α-smooth muscle actin (α-SMA), desmin, and vimentin. Results—The phenotype of the muscularis mucosa was α-SMA positive, desmin positive, and vimentin weakly positive, whereas the eosinophilic spindle cells showed a decreased degree of immunoreactivity for α-SMA and desmin in particular, and an increased degree of immunoreactivity for vimentin. The degree of phenotypic difference between the muscularis mucosa and the eosinophilic spindle cells was greater in the eosinophilic spindle cells in the centre of the invasive area that were not continuous with the muscularis mucosa than in the eosinophilic spindle cells continuous with the muscularis mucosa. Conclusions—These findings suggest that the smooth muscle cells of the muscularis mucosa change their phenotype to become eosinophilic spindle cells, namely myofibroblasts, in the early invasive area of colorectal adenocarcinoma.

Severe diffuse atherosclerotic lesions of right gastroepiploic artery graft.

The incidence of arteriosclerosis of the right gastroepiploic artery (RGEA) has not been widely known. We experienced one patient in whom the RGEA had severe diffuse atherosclerotic lesions and luminal narrowing, and was therefore determined to be unsuitable as a coronary bypass conduit at operation.

Parahisian Radiofrequency Catheter Ablation in Dogs: Comparison of the above-valve and below-valve approaches

In patients with an accessory pathway close to the His bundle, radiofrequency catheter ablation (RFCA) requires additional care to avoid damage to the normal conduction system. To assess differences between approaches from above or below the tricuspid valve (TV), we performed RFCA in 20 dogs (from above, group A, n=10; from below, group B, n=10). RF energy with temperature control at 60° 60 seconds was administered at the site where a small His potential was recorded from the ablation catheter guided by fluoroscopy and transesophageal echocardiography (TEE) (in the latter six dogs). Before and after RFCA, electrophysiological testing was performed and histological findings were compared. An ablated lesion was created in 7 of 10 (2 of 2 guided by TEE) dogs in group A and 5 of 10 (3 of 4 TEE) dogs in group B. In group A, an ablated lesion involved the atrium and ventricle in the anterior site of His bundle, but the lesion was only in the ventricle in group B. An atrioventricular block (AVB) and severe damage to the penetrating bundle was observed in one dog of group A. A large hematoma on the TV was made in 2 dogs and the complete right bundle branch block (CRBBB) occurred in 3 dogs of group B. The approach from below the TV was safer than that from above the TV in parahisian RFCA, because it did not create an AVB, although it has a high incidence of CRBBB and associated technical difficulties.