Hemopoietic neoplasms in lethally irradiated mice repopulated with bone marrow cells carrying the human c-myc oncogene: a repopulation assay.

Bone marrow (BM) cells from two transgenic mice carrying the human c-myc oncogene were separately harvested, and each sample was injected into 25 lethally irradiated mice. We observed the contribution of the myc gene to the occurrence of hemopoietic neoplasms in the BM-repopulated mice, establishing a new experimental system for analyzing oncogene expression in the hemopoietic system in vivo. The hybrid gene that was transferred into the original transgenic mice was a combination of the human c-myc gene with a regulatory unit consisting of a murine immunoglobulin-heavy chain with an SV40 early-T promoter gene (Ig/Tp-myc). Among the transgenic lines, the tested BM cells were chosen from two lines that had been low-prone in leukemia; in these lines hemopoietic neoplasms did not appear for greater than or equal 200 days after birth. Lethally irradiated controls received BM cells from litters of transgenic mice that did not carry c-myc. The lifetime incidence of hemopoietic neoplasms was 94% and 91% in the two groups of mice repopulated with myc+ BM. By contrast, only 15% of control mice with myc- BM developed hemopoietic lesions. The incidence of hemopoietic malignancies combined with nonthymic lymphomas and myeloma cases (88% and 65%) was higher in the repopulated mice than the incidence of pre-B cell lymphomas in the original transgenic lines (56%). Thirty-two of the 40 myc+ mice that were examined showed the presence of the transferred gene in either the normal hemopoietic tissue or in the hemopoietic neoplasm. Furthermore, 18 of 22 hemopoietic neoplasms studied by Northern hybridization expressed mRNA from the transgenic gene; in other four neoplasms, expression was weak or absent.     

Effects of smoking and drinking on excretion of hippuric acid among toluene-exposed workers

Summary In order to investigate possible effects of smoking and drinking on the metabolism of toluence in occupational settings, 206 toluene-exposed men (mean age: 31.4 years) in shoemaking, painting, or surface-coating workshops together with 246 nonexposed control men (36.8 years) were studied for the time-weighted average intensities of exposure to toluene, hippuric acid concentration in shift-end urine samples, and the two social habits of smoking and drinking. The mean daily consumptions of cigarettes and ethanol were about 20 pieces and 10 g among smokers and drinkers, respectively. The geometric mean toluene concentration among the exposed subjects was about 20 ppm, with a maximum of 521 ppm. Regression analysis after classification of the subjects by smoking and drinking clearly demonstrated that the two social habits, when combined, markedly reduce the hippuric acid level in the urine of workers exposed to was a significant association between smoking and drinking habits, which hindered separate evaluation of the effects of the two habits on toluene metabolism. Comparison of the present results with the findings reported in the literature, however, suggested that the observed effects may be attributable to smoking rather than to drinking habits.     

Ultrastructural localization of adhalin in normal murine skeletal myofiber

The ultrastructural localization of adhalin and its relations to dystrophin, β-dystroglycan, and β-spectrin were studied in normal murine skeletal myofibers. The C-terminal peptides of adhalin and β-dystroglycan were synthesized based on their cDNAs, and the affinity-purified antibodies against these peptides were produced. Single-immunolabeling electron microscopy showed that the adhalin was located just inside the muscle plasma membrane or inside the myofiber a short distance from the plasma membrane. The adhalin signal was also noted at the sarcoplasmic side of plasmalemmd invaginations or at vesicular structures in subsarcolemmal areas. Double-immunogold-labeling electron microscopy disclosed a similar localization of dystrophin, β-dystroglycan, and β-spectrin. The close association of adhalin with dystrophin or β-dystroglycan was demonstrated by formation of doublets by signals of antibodies of adhalin with those of dystrophin or β-dystroglycan and was confirmed by statistical analyses. This study demonstrated that the location of adhalin is close to that of dystrophin and β-dystroglycan at the muscle plasma membrane.     

Glossopharyngeal neurinoma causing symptomatic hemorrhage: case report

A 86-year-old man was admitted to our hospital because of swallowing disturbance and deterioration of consciousness. He had been aware of hearing disturbance on the right side for twelve months. Computed tomography (CT) scan demonstrated an inhomogeneous hyperdense mass lesion, 3.2 X 2.3 cm in size, at the right cerebello-pontine angle, and ventricular enlargement with intraventricular hemorrhage. Skull tomogram revealed destructive enlargement of the right jugular foramen. The angiogram showed avascular mass with elevation of anterior inferior cerebellar artery, and downward shift of posterior inferior cerebellar artery. Operative and histological findings were compatible with glossopharyngeal neurinoma of Antoni type A dominance. This tumor had numerous abnormal vessels probably causing massive hemorrhage. Only fifteen cases of intracranial neurinoma with symptomatic hemorrhage have been reported in the world literature. This case is reported as the sixteenth one and the first glossopharyngeal neurinoma among them. Possible etiology of such hemorrhage is discussed.     

A case of supravalvular aortic stenosis with spontaneous remission of peripheral pulmonary stenosis

A 14-year-old junior high school boy was admitted to our institute. Previously he had been diagnosed as having peripheral pulmonary stenosis (Gay's classification, type IV) at the age of 2 years and 10 months. On this occasion, however, a diagnosis of supravalvular aortic stenosis was made, with a pressure gradient of about 120 mmHg, and all examinations showed spontaneous remission of peripheral pulmonary stenosis. He underwent a successful standard aortoplasty. This is the first reported case of spontaneous remission of peripheral pulmonary stenosis.     

Pulmonary sequestration associated with asymptomatic aspergillosis.

Intralobar pulmonary sequestration associated with asymptomatic aspergillosis is a rare case. We describe the case of a 65-year-old woman with intrapulmonary sequestration, anomalous systemic arterial supply to the left lower lobe and aspergillosis who underwent left lower lobectomy and ligation of an anomalous artery by Video-Assisted Thoracoscopic surgery (VATS). Pathological examination showed the parenchymal distortion and chronic inflammation. Aspergillus were found in the cyst. VATS lobectomy for intralobar pulmonary sequestration is a safe and valid procedure.     

Accumulation of cyanide and thiocyanate in haemodialysis patients.

BACKGROUND: Cyanide is a toxic agent, and its detoxification product, thiocyanate, may be a major pathogenetic substance in uraemia. Recent studies examining the myeloperoxidase(MPO)/thiocyanate system have suggested a link between thiocyanate and atherosclerosis. However, inaccuracies in conventional assays for cyanide and thiocyanate have limited the understanding of their metabolism in haemodialysis (HD) patients. METHODS: We used high-performance liquid chromatography to measure cyanide in erythrocytes and thiocyanate in plasma in 43 HD patients and in a group of 46 healthy controls that included 15 current smokers. To clarify the metabolic conversion of cyanide to thiocyanate in uraemic patients, we also measured cysteine and sulfate. We then used stepwise regression analysis to analyse factors that determine erythrocyte cyanide and plasma thiocyanate. RESULTS: Mean cyanide and thiocyanate were significantly greater in HD patients than in non-smoking controls. However, cyanide was far below lethal concentrations in dialysis patients. Thiocyanate was six to seven times greater in HD patients than in non-smoking controls, and decreases in thiocyanate following dialysis were only 19.3+/-3.5%. Multiple regression analysis showed a positive correlation between cyanide and thiocyanate in controls, but a negative correlation in HD patients. In patients, an inverse relationship between thiocyanate and BUN was also observed. CONCLUSIONS: The elevation of thiocyanate in patients undergoing dialysis probably is secondary to both limited efficiency of HD and deranged metabolism of cyanide and thiocyanate. Because thiocyanate is a preferred substrate for MPO, it may play a role in uraemic complications including cardiovascular events.     

Pericardial effusion following pulmonary resection

Objective Postoperative pericardial effusion commonly occurs after open heart surgery. However, after general thoracotomy such as pulmonary resection, there have been few reports of pericardial effusion. The purpose of this study is to investigate patients with pericardial effusion following pulmonary resection.Methods: Among 2,385 patients with pulmonary resection for lung neoplasm in our institute, eight patients, whose pericardium had never been opened during the operation, developed pericardial effusion. The clinical characteristics of the eight patients were analyzed.Results: Pericardial effusion after pulmonary resection was divided into two subtypes: pericardial effusion in three patients with left thoracotomy occurring within 30 days postoperatively, and pericardial effusion in the remaining five patients with right thoracotomy occurring more than 30 days postoperatively. Pericardiotomy or pericardiocentesis was performed in three symptomatic patients, and the remaining five asymptomatic patients were treated with diuretics. Pericardial effusion disappeared in three of the five patients about 1–3 months after the conservative treatment, while, in the remaining patients, because pericardial effusion had increased gradually, pericardiocentesis was performed.Conclusion: From our experience, the treatment strategy of drainage for early pericardial effusion and diuretics for late pericardial effusion seems to be appropriate. (Jpn J Thorac Cardiovasc Surg 2006; 54:193-198)