The determination of thymidylate synthetase inhibition for testing fluoropyrimidines--pharmacokinetics and metabolism of carmofur (HCFU) in patients with gynecologic malignancies--Tokai HCFU Study Group for Gynecologic Malignancies

The pharmacokinetics and metabolism of carmofur (HCFU) were studied. Sixty-six patients were administered 100 mg of HCFU orally, and the plasma levels of the HCFU fraction (HCFUf) and 5-fluorouracil (5-FUra) were determined at 0, 1, 2, 4 and 6 hours. The average half-life of HCFUf and 5-FUra were 1.05 and 1.31 hours, and the average areas under the curves (AUC) of the plasma concentration were 6.51 hr X mcg/ml and 0.46 hr X mcg/ml, respectively. Surgical specimens of the tumors were obtained about three hours after the administration and assayed for HCFUf. 5-FUra fluorodeoxyuridine-monophosphate (FdUMP), deoxyuridine-monophosphate (dUMP), total thymidylate synthetase (TS total), and non-FdUMP-bound free enzyme (TS free). The TS inhibition rate (IR) was calculated by the follow method: IR = (TS total-TS free)/TS total X 100 levels of the TS total varied from not-detected (less than 0.10 pmol/g) to 20.5 pmol/g. The average FdUMP: dUMP ratio was 3.44 X 10(3), However, more than 80% inhibitions of TS were observed in nine cases (21.4%). The correlation indicates between TS IR and tissue FdUMP level or FdUMP: dUMP ratio were 0.57 and 0.62 in ovarian malignancies respectively. No significant correlations were observed between TS inhibition and levels of tissue 5-FUra or AUC of 5-FUra.     

Cloning and analysis of a gene (sms13) encoding sannamycin B-glycyltransferase from Streptomyces sannanensis and its distribution among actinomycetes.

A gene encoding sannamycin B-glycyltransferase (sms13) of Streptomyces sannanensis IFO 14239 was identified by cloning and complementation of S. sannanensis mutant SN13 which is blocked at the interconversion of sannamycins B and A. The cloned DNA fragment also permitted the conversion of fortimicin B to A both in S. sannanensis SN13 and Streptomyces lividans TK23. DNA sequences similar to sms13 were detected in all five producers of the fortimicin-group antibiotics, Micromonospora olivasterospora ATCC 21819 (fortimicin-producer), Micromonospora sp. strain SF-2098 ATCC 31580 (SF-2052), Dactylosporangium matsuzakiense ATCC 31570 (dactimicin), Streptomyces tenjimariensis ATCC 31603 (istamycin), and Saccharopolyspora hirsuta ATCC 20501 (sporaricin). This suggests that these genes of similar function from different genera were derived from a common ancestral gene.     

Experimental model of chronic tonsillar herniation associated with early stage syringomyelia

This report describes an experimental model of chronic tonsillar herniation and its effects on the spinal cord. In ten rats, a small piece of chemically induced mammary cancer was transplanted to the supraoccipital bone. In all cases, the transplanted cancers grew into the posterior fossa, destroying the supraoccipital bone and compressing the cerebellum extradurally. In six of the ten rats, tonsillar herniation was observed at 8–14 weeks after transplantation. Transdural infiltration of the tumor cells was not apparent in any animal. In those rats with tonsillar herniation (n=6), the spinal cord from the C5 to the T8 segments showed enlargement of the central canal without exception. Histological examination revealed the following changes: stretching and thinning of the ependymal cells; swelling of the astrocytic processes; and extracellular edema, predominantly in the dorsal gray matter, but also in the ventral inner portion of the dorsal column. In the control group (n=4) and those rats without tonsillar herniation (n=4), such histological changes of the spinal cord were not observed. Although the lesions can not be regarded as representing mature syringomyelia, they most likely constitute an earlier evolutionary stage.     

A case of serous cystadenoma of the pancreas with focal malignant changes

Summary We present a serous cystadenoma of the pancreas with focal malignant changes, and describe its characteristic histological features. On gross examination, a tumor was present on the anterior surface of the body of the pancreas and measured approx 25×25⋻20, mm. Microscopically, most tumor cells showed the typical histological features of serous cystadenoma, characterized by a microcystic architecture and glycogenrich cells with a uniform and bland appearance. However, in some areas, a tendency to papillary structures with fibrovascular cores was noted. These papillary lesions were composed mainly of nonmucinous, glycogen-poor epithelial cells, the nuclei of which showed a mild atypia. In addition, vascular and perivascular invasion was focally observed. However, there was no clinical evidence of local or distant metastasis. From these findings, we diagnosed this lesion as a serous cystadenoma of the pancreas with focal malignant changes rather than a serous cystadenocarcinoma of the pancreas.     

Comparison of DNA fingerprinting by PFGE and PCR-RFLP of the coagulase gene to distinguish MRSA isolates

Staphylococcus aureus isolates were collected from epidemiologically unrelated clinical sources in Japan between 1991 and 1993. A total of 40 isolates, five each of eight coagulase types, were analysed by polymerase chain reaction (PCR) of the coagulase gene, PCR-restriction fragment length polymorphism (RFLP) after AluI digestion, and pulsedfield gel electrophoresis (PFGE) of chromosomal DNA after SmaI digestion. The efficiency of discrimination among the isolates increased in the order of PCR < PCR-RFLP < PFGE, yielding five, 13 and 31 different types, respectively. To assess the clinical use of these methods, 42 additional methicillin-resistant S. aureus (MRSA) isolates collected from 27 inpatients in a hospital were analysed. PFGE and PCR-RFLP were able to discriminate 11 and four types, respectively. PFGE analysis detected cross-infection between four postoperative patients in an intensive-care unit, and in six neonates in intensive care. We conclude that of the three methods tested, PFGE analysis currently allows the most effective discrimination of MRSA strains.