Organization of Mouse DNA Polymerase β Gene Silencer Elements and Identification of the Silencer-binding Factor(s)

Different portions of the 5-upstream region of the mouse DNA polymerase β gene were combined with bacterial chloramphenicol acetyltransferase (CAT) gene of the CAT vector. Transfection of these recombinant plasmids into mouse NIH/3T3 cells has revealed that each of the previously identified two negatively acting regions (silencers I and II) of this gene consists of multiple sub-domains. The distal silencer (silencer I) at around -1.5 kb consists of four sub-domains (-1852 to -1667, -1663 to -1616, -1564 to -1525 and -1355 to -1257). The promoter-proximal silencer (silencer II) at around – 0.5 kb consists of two functional domains (- 681 to – 523 and – 490 to – 447) separated by a neutral region of 33 base pairs. Silencer II functioned efficiently when silencer I was deleted. Conversely, the distal silencer I functioned efficiently when silencer II was deleted. Thus, these silencers functioned redundantly to each other in NIH/3T3 cells. Nucleotide sequence analysis revealed no extensive sequence similarity between these two silencers. Significant sequence similarity is present between a distal portion of silencer II and the c-myc gene silencer, and also between a proximal portion of silencer II and the mouse F9 cell-specific silencer. A protein factor(s) that specifically bound to the silencer elements was detected in nuclear extracts of NIH/3T3 cells and mouse liver in which DNA polymerase β was expressed at a rather low level. The same binding factor(s) can bind to both silencer I and II regions, although its affinity for silencer II is much higher than that for silencer I.     

Colonic Angiomyolipoma

Abstract: Angiomyolipoma is a rare benign tumor which usually occurs in the kidney with tuberous sclerosis. We encountered a case of angiomyolipoma of the cecum not associated with tuberous sclerosis. To our knowledge, this is only the third case reported in the international literature.     

Frontal Lobe Tumor Associated with Late-Onset Seizure and Psychosis: A Case Report

Abstract: This is a report of a 55-year-old woman with a 6-year history of uncontrollable complex partial seizure and severe delusion. A computed tomography (CT) brain scan showed a nonenhanced low density area with an ill-defined mass located at the right frontal lobe. Magnetic resonance imaging (MRI) demonstrated an area of hyperintensity on T₂-weighted images. After a tumorectomy, the patient gradually recovered from the seizures and delusion. A histological diagnosis showed a mixed oligoastrocytoma or dysembryoplastic neuroepithelial tumor (DNT). The clinical and pathological features of the tumor as well as its relation to psychosis were discussed.     

The double fold free radial forearm flap for skin large fistule closure after pharyngoesophageal operation

Reported herein is a case who underwent a one-stage closure of pharyngostome utilizing a double fold free radial forearm flap (FRF) was performed. By use of a thin and large FRF, this operative method permits the closure of a large fistula and thus satisfies cosmetic requirements.     

Changes in surgical strategies for peptic ulcers before and after the introduction of H2-receptor antagonists and endoscopic hemostasis

A total of 902 surgical patients with peptic ulcer disease were evaluated to clarify the effects of H₂-receptor antagonists and endoscopic hemostasis on surgical treatment. Following the introduction of these treatments to our institute in 1982, the number of operations performed annually decreased by 40%, or 36 cases per year. However, a remarkable increase in the frequency of surgical emergency intervention since 1982 was concurrently observed, with the ratio of emergency procedures to the total number of operated cases increasing to 72.5% in the last 5 years of the study. Moreover, intractability as an indication for surgery decreased to 34.1%, compared with an increase in the number of patients with bleeding and perforated ulcers requiring operation. There were 13 postoperative deaths recorded (1.4%). All of the deaths were in patients who had undergone emergency surgery in poor health. Of these 13 patients, 10 had bleeding ulcers. A study of bleeding ulcers for which endoscopic hemostasis had been unsuccessful revealed that shock on admission and a concomitant medical condition had been evident in all the patients who died, and in 52.2% and 30.4% of the survivors, respectively. The current study suggests that the frequency of high-risk patients requiring surgery is increasing since the introduction of H₂-receptor antagonists and endoscopic hemostasis, and thus, prompt surgical treatment and intensive management for such patients is essential.     

Postoperative delirium in plastic or dermatologic surgery

Postoperative delirium is a serious and commonly encountered problem in the field of surgery. But in plastic surgery, this problem is rarely reported. We restrospectively examined the incidence of delirium using the 12-point Delirium Rating Scale in 364 inpatients treated over a 3-year period, whose ages ranged from 56 to 96 years. Surgery for malignant tumors was the most frequent type of surgery. The overall incidence of delirium was 1.4%; but when distributed by disease, patients with extramammary Paget’s disease showed the highest incidence. We then examined the records of patients with extramammary Paget’s disease or carcinoma treated in the ten previous years. The incidence in this group was 20.7%, and all of them were men. The average age of the male patients manifesting delirium was 79.8 years and that of those who did not develop delirium was 73.2 years. As many reports suggest, in our patients, precipitating factors such as physical restraints, bladder catheterization, and risk factors such as old age, seemed to have been strongly related to the occurrence of delirium. In conclusion, postoperative delirium is rarely observed in the field of dermatologic or plastic surgery. In our practice, the incidence of delirium was particularly high in patients with extramammary Paget’s disease, especially in elderly male patients. Close attention must be paid to this subset of patients to prevent delirium.     

Extremely tortuous superior cerebellar artery

European Radiology -     

Neurotoxicity of petroleum benzine compared with n-hexane

Summary Petroleum benzine is one of the mixtures of organic solvents containing n-hexane. The occurrence of polyneuropathy in the workers using petroleum benzines is attributed mainly to n-hexane, though other hydrocarbons present are also suspected of having some neurotoxicity or some potential which could modify the neurotoxicity of n-hexane. The present experiment was performed in order to clarify the toxicity of petroleum benzine to the peripheral nerve and compare it with that of n-hexane.Forty rats were randomly divided into five groups. The groups were exposed to 200 ppm n-hexane, 500 ppm n-hexane, and petroleum benzine vapor containing 200 ppm n-hexane or 500 ppm n-hexane, together with aliphatic and aromatic hydrocarbons for 12 h a day for 24 weeks. The body weight, motor nerve conduction velocity, motor distal latency, and mixed nerve conduction velocities were measured before exposure and every 4 weeks of exposure. A rat from each exposed group was histopathologically examined after 24 weeks' exposure.The function of the peripheral nerve was conspicuously impaired by 500 ppm n-hexane, slightly impaired by 200 ppm n-hexane and petroleum benzine containing 500 ppm n-hexane, and even less impaired by petroleum benzine containing 200 ppm n-hexane. Degenerations of the myelin sheaths and axons were demonstrated in all exposed groups upon examination of the raveled tail nerves. Thus, the experiment revealed that petroleum benzine could impair the peripheral nerves, while some components of petroleum benzine were considered to inhibit the neurotoxicity of n-hexane.This investigation was partly supported by a grant for scientific research from the Chiyoda Mutual Life Foundation in 1980–1981     

Meningeal large granular lymphocyte lymphoma

A 57-year-old man who presented with leptomeningeal lymphoma was reported. The lymphoma cells in the cere-brospinal fluid were large in size, had atypical nuclei and contained many azurophilic granules in their pale cytoplasm, all of which were consistent with malignant lymphoma of large granular lymphocytes (LGL). Immunohistochemically, tumor cells were positive for cyto-plasmic CD3, UCHL-1, and CD56, markers of natural killer (NK)cells. Epstein-Barr virus encoded small RNA (EBER) was detected in tumor cells by in situ hybridization. No evidence of parenchymal central nervous system or systemic tumor was identified, although at autopsy microscopic lympuoma involvement was found in the pituitary gland and kidney. To our knowledge this is the first autopsy case report of primary meningeal LGL lymphoma.