Acta Medica Okayama 48巻 4号

The aim of this study was to investigate the usefulness of magnetic resonance (MR) imaging in the evaluation of renal function, with particular attention to the effects of water load. Ten healthy volunteers underwent dynamic MR imaging after an injection of gadolinium diethylene-triaminepenta-acetic acid (Gd-DTPA) as a contrast agent to evaluate renal function by the following four methods: the positive method [longitudinal relaxation time (T1) shortening is the dominant effect], the negative method [transverse relaxation time (T2) shortening is the dominant effect] and two intermediate methods by switching the Gd-DTPA concentrations used in the positive and negative methods. A prolonged cortical peak time and a reduced medullary peak level were observed by the positive method under a dehydrated condition, suggesting that these variables were slightly influenced by Gd-DTPA concentrated in the medulla. By the negative method, low signals due to T2* (T2* is the effective transverse relaxation time, typically shorter than T2) shortening appeared in the medulla under normal conditions, but these signals were unclear when the subject was under an overhydrated condition. These results indicate that water metabolism, in addition to imaging parameters and Gd-DTPA dose levels, should be considered when renal function is evaluated by dynamic MR imaging. Analysis of both the pattern of MR images and the time-signal intensity curves may be useful in the evaluation of renal function. The results also indicate that the positive method is preferred when the patient is overhydrated as it allows the evaluation of the local renal kinetic function by recording changes in the regional contrast agent levels.

In this study, we investigated serum-soluble interleukin-2 receptor (sIL-2r) and neopterin (NPT) levels in five patients with severe postoperative infections. A total of 25 synchronous determinations of sIL-2r and NPT were performed. A marked increase in sIL-2r and NPT levels was observed, and the increase in sIL-2r was significantly correlated to that of NPT which is a marker of macrophage activity. These results suggest that macrophages are involved in the stimulation of sIL-2r release, representing a potentially negative biological effect. The results indicate that sIL-2r may be a useful indicator of the efficacy of antibiotics and of prognosis.

Both prolidase and prolinase from the human prostate were separated into two peaks by TSK DEAE-5PW chromatography. These peaks of prolidase isozymes I and II differed from each other in their responses to preincubation with Mn2+, their substrate specificity, optimal pH, and heat stability. The molecular weights of prolidases I and II were estimated to be 110,000 and 165,000, respectively, by gel filtration. Substrate specificity of prolinase peaks I and II was almost the same, but they differed in optimal pH and heat stability. The molecular weights of prolinases I and II were about 85,000 and 63,000, respectively. These results indicate that two isozymes of prolidase and of prolinase, which differ in various characteristics, are present in the human prostate.

Neurons with strongly negatively charged surface coats were recognized in mammalian, avian, reptilian, amphibian and piscine brains. Many large-sized neurons had strongly negatively charged surface coats in the visual cortex and brain stem of the cow, cat, guinea pig, mouse, quail and parakeet. Such neurons were also seen in the brain stem of the lower vertebrates such as the house lizard, Japanese terrapin, bullfrog, newt, carp and sweetfish.

The sensitivity and specificity of single cell polymerase chain reaction (PCR) were studied. Its high sensitivity enabled detection of a single-copy gene, such as human T-lymphotropic virus type I genome in paraffin sections. The rate of obtaining positive signals with this method was affected by the number of copies of the gene in the target cell. Specificity was satisfactory if the procedure was properly and carefully followed. Since the single cell PCR is a time-consuming method which requires skill and experience to pick up the target cells accurately, the applicability of this method is limited. It works best when it is used to analyze a single or a few copy genes in histologically identified cells.

Familial adenomatous polyposis (FAP) is a well-known autosomal dominant disorder characterized by the formation of multiple adenomatous polyps of the colon. Gardner's syndrome is a variant of familial polyposis coli, and both can be associated with colonic or extracolonic benign and/or malignant tumors. It has been widely recognized that an adenocarcinoma of the colon develops in virtually all cases, usually at an earlier age, if polyps are left untreated. Families of four individuals diagnosed of FAP were surveyed and 56 relatives of the families were examined. Of these 56, 21 had multiple colon polyps, 3 of whom had early-stage adenocarcinomas. We consider that familial survey of FAP individuals can be of considerable benefit for this high-risk population due to the autosomal nature of the disease, allowing diagnosis of an associated cancer at an earlier stage.

The accumulation of polymorphonuclear leukocytes (PMN) in synovial fluid is a common feature of rheumatoid arthritis (RA). We studied the chemotactic response of PMN obtained from the synovial fluid and from the peripheral blood of patients with RA using a modified Boyden's method, in which interleukin-8 (IL-8) or N-formyl-methionyl-leucyl-phenylalanine (FMLP) was used as a chemotactic agent. The IL-8-induced response of peripheral blood PMN from 15 patients with RA did not differ from that of 15 healthy controls. A decreased chemotactic response to IL-8 was, however, observed in PMN from the synovial fluid of 12 patients with RA compared with peripheral blood cells of the same individual. This defective chemotactic ability of PMN was inversely correlated with the number of infiltrating cells in the synovial fluid. We also obtained similar results with FMLP. These results indicate that the chemotactic ability of PMN may be reduced after migrating to the synovial fluid.

To clarify the influence of the introduction of metal bats on the physique and batting records of the players in the National Summer High School Baseball Tournaments, a comparative analysis was conducted between height, body weight, body-weight ratio (body weight/height), batting average and home run average of the best four teams' players (n = 493) and those of the other teams' players (n = 4,590) in three periods: the period of the use of wooden bats, that of the use of both wooden and metal bats and that of the use of metal bats. In the period of metal bat use, the mean values of physique of the best four teams' players were significantly larger (P < 0.05) and their average number of home runs was significantly higher than those of the other teams' players (P < 0.01). The only significant differences between the two groups in those indices for each time period were for height in the wood and metal/wood periods. This study demonstrated that the differences between the home run average and physique, including height, body weight and body-weight ratio of the best four teams and the rest of the teams were the greatest after the use of metal bats. These findings suggest that the importance of the home run average increased and was associated with large-size of physique after the use of metal bats in the National Summer High School Baseball Tournaments.

External capacitive heating is the usual method of electromagnetic wave heating, in which the tumor is caught and heated between two opposite applicators. Using a phantom, the authors developed and evaluated the performance of a new capacitive heating applicator designed for simultaneous radiohyperthermotherapy (SRH) in which the electron beam irradiation is provided from above an external capacitive heating applicator for the treatment of superficial and shallow-seated tumors. The trial applicator was constructed to fulfill the following conditions: 1. use of an electrode plate which does not affect the electron beam depth dose, 2. a uniform thickness to maintain flatness of the electron beam, and 3. a cooling function to prevent damage to normal skin tissue and enhance the therapeutic gain factor. This applicator was comprised of a 0.1-mm-thick copper electrode and a 5-mm-thick cooling chamber. The depth of the 80% dose of the new applicator was 21 mm with a 9-MeV electron beam and 36mm with a 15-MeV electron beam, which was comparable to the effect of a conventional irradiation bolus. The temperature distribution produced by the trial applicator was symmetrical on both sides from the center of the applicator. The 50% specific absorption rate region was 6.4 cm wide at a depth of 1 cm from the phantom surface and 2.8 cm wide at a depth of 3 cm. There have been no previous reports on the development of an external capacitive heating applicator designed for the SRH of superficial and shallow-seated tumors; this is the first such report.(ABSTRACT TRUNCATED AT 250 WORDS)