Effects of repeated inhalation-exposure to fenitrothion powder on blood cholinesterase activity in rats

Effects of repeated exposure to Fenitrothion (Sumithion) powder on erythrocyte membrane acetylcholinesterase (AChE) and plasma cholinesterase (PChE) were studied. Rats (Wistar, male) were exposed to fenitrothion powder for 2 hrs/day, 5 days/week for up to 3 months. The suppression of AChE and PChE increased as the exposure period and exposure concentration increased, although no suppression of AChE was found after a single 4-hr exposure. The persistence of AChE inhibition after the termination of exposure increased with the increase of the exposure period and was longer than that of PChE. Therefore, the AChE activity seems to be useful in examining the response to the repeated exposure to fenitrothion powder.     

Histopathological observations on orbital fatty tissue in dysthyroid ophthalmopathy

Seventeen specimens of orbital fatty tissue taken from cases of dysthyroid ophthalmopathy at the time of operation were observed by light and electron microscopy, and also by immunohistochemical staining. The pathological changes observed were infiltration of the chronic inflammatory cells, deposit of fibrin, sclerosis of vascular wall, occlusion of the vascular lumen, and accumulation of hydrophilic mucopolysaccharide. Immunoglobulin G was detected in fat cells and lymphocytes, and some of the infiltrating lymphocytes were determined to be T cells, by immunohistochemistry. These findings suggested that the pathology of the dysthyroid ophthalmopathy was closely related to the chronic inflammation induced by the immune reaction. The exophthalmos was considered to occur due to edema secondary to chronic inflammation and accumulation of the mucopolysaccharides.     

A nonspecific colonic ulcer occurring after hepatectomy: Report of a Case

We herein report the case of a 53-year-old man with a nonspecific acute colonic ulcer whose liver function deteriorated after he had undergone hepatectomy. He was referred to our hospital for a hepatoma caused by hepatitis B virus and a right hemihepatectomy was performed. His liver function was poor after the operation, and minor complications such as pleural effusion and biliary fistula developed. A large amount of melena was seen 29 days after the hepatectomy and he developed hemorrhagic shock. Superior mesenteric arteriography revealed pooling of blood in both the hepatic flexure of the ascending colon and the cecum. An emergency right hemicolectomy was performed. There was a 5 x 1-mm ulcer 18 cm distal to the ileocecal valve. Numerous erosions were observed to be scattered throughout the colonic mucosa. The patient recovered slowly and was discharged 6 months after the hepatectomy. This is the first report of an acute colonic ulcer that could have been caused by liver dysfunction.     

Lack of biliary excretion of Cd linked to an inherent defect of the canalicular isoform of multidrug resistance protein (cMrp) does not abnormally stimulate accumulation of Cd in the Eisai hyperbilirubinemic (EHB) rat liver

A new mutant, the Eisai hyperbilirubinemic (EHB) rat, shows no inherent expression of the canalicular isoform of the multidrug resistance protein (cMrp) in the liver. It has defective biliary secretion of organic anions such as bilirubin glucuronides, bromosulfophthalein (BSP), cysteinyl leukotrienes, glutathione (GSH) and bile acid sulfate and glucuronides. When rats were injected intravenously with CdCl₂, biliary excretion of Cd over 30 min was 0.28% and 0.004% of the total dose in Sprague-Dawley (SD) and EHB rats, respectively. Six SD rats and five EHB rats were fed a diet containing Cd. Bile Cd was detected at the level of 2 ng/20 min in SD rats, but not in EHB rats. There was no significant difference of hepatic Cd concentration between SD and EHB rats. Furthermore, there were no significant differences of renal and intestinal Cd, and hepatic and renal metallothionein (MT) concentrations between the SD and EHB groups. Biliary excretion of reduced-GSH for 20 min was 1.3 ± 0.3 mg and 3.6 ± 0.9 μg in SD and EHB rats, respectively. Our results suggest that hepatobiliary excretion of exogenous Cd is mediated mainly via carrier transport, including a cMrp or GSH carrier, but that the lack of the transport pathway does not contribute to abnormal accumulation of Cd in the liver. Received: 12 August 1996 / Accepted 7 November 1996     

Sisters with mercury exposure

The same iron pot in which their father had boiled lead with mercury (from a glass thermometer) for the purpose of alchemy, was also used for cooking in the kitchen. Although his wife had died of mercury poisoning, and his 14-year-old and 11-year-old daughters were found to excrete 322 and 455 micrograms/l mercury in the urine, respectively, (1-10 micrograms/l in controls), he stubbornly refused to give permission for them to be examined further. Nine months later, the daughters were permitted to be sent to our clinical ward. While the blood level of mercury had already come down to near normal, its excessive deposition in hair, kidneys and other parts of the body as well as its excessive urinary excretion, were still persistent (beyond tenfold the normal). According to our measurement values, mercury ranged from 14 to 49 micrograms/g in every 1-cm-piece of 10 cm hair of the elder sister, and ranged from 21 to 85 micrograms/g in 14 cm hair from the younger sister. About a 75% decrease in mercury deposition was estimated during these 9 months, based on the speculation of 1.5 cm/month hair-lengthening.     

An immunocytochemical demonstration of calcineurin in human nerve cell tumors. A comparison with neuron-specific enolase and glial fibrillary acidic protein

Human central and peripheral nerve cell tumors were examined in detail using antibodies to calcineurin, glial fibrillary acidic protein (GFAP) and neuron-specific enolase (NSE). Forty-eight formalin-fixed and paraffin-embedded specimens of human neuronal tumors, including 27 medulloblastomas, were examined. Calcineurin-positive cells were found in all peripheral nerve cell tumors and the two gangliogliomas, whereas 20 of the 27 medulloblastomas and one of the two cerebral neuroblastomas did not contain calcineurin-positive cells. Differentiation of cells along the neuronal lines was positively correlated with calcineurin immunoreactivity. NSE-positive cells were found in all of the tumors with the exception of the one cerebral neuroblastoma. NSE immunoreactivity was not invariably consistent with calcineurin immunoreactivity and non-neuronal cells were often positive. Calcineurin-positive cells were all devoid of GFAP, but NSE-positive cells expressed GFAP in some tumors. GFAP-immunoreactive cells were found only in central nerve cell tumors, and not in peripheral tumors. In addition, GFAP-positive cells in some tumors such as retinoblastoma and medulloblastoma morphologically revealed not only neoplastic but also reactive astrocytic features.     

Relationship between tumor DNA ploidy and regional lymph node changes in lung cancer.

Seventy-four patients with lung cancer, resected consecutively from April 1989 to August 1990, were divided into (1) 21 with diploid tumors having a single G0/G1 peak and a coefficient of variation (CV) of 4.9 or less, (2) 18 with peridiploid tumors having a single G0/G1 peak and a CV at 5.0 or more, and (3) 35 with aneuploid tumors having multiple G0/G1 peaks. Aneuploid tumors had higher frequencies of lymphatic invasion and metastasis to the mediastinal lymph nodes. To evaluate the relationship between ploidy tumor status and immunologic competence of the regional lymph nodes, histologic findings and the proportion of killer T-lymphocytes were examined in the dissected lymph nodes. Aneuploid tumors had significantly lower proportions of paracortical hyperplasia and killer T-lymphocytes than did diploid and peridiploid ones in the nonmetastatic lymph nodes of N0 and N1 disease. These findings suggest the possibility that a decline in the antitumor competence of these lymph nodes could cause metastasis to the nodes. The recurrence rates were 19% in diploid, 33% in peridiploid, and 54% in aneuploid tumors, and the 2-year survival rates were 87%, 78%, and 44%, respectively. Peridiploid tumors showed intermediate values between diploid and aneuploid in terms of immunologic competence, recurrence rate, and survival. They were assumed to have a different proportion of aneuploid cells than the other two.