[A case of total agenesis of the corpus callosum. The diagnosis by NMR-CT and the localization of the speech center].
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Biomedical subjects
Publications and source records attributed to M Sakamoto.
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A case of adenocarcinoma of the body of the pancreas in a 13-year-old girl is reported. The gross appearance of the tumor revealed apparent encapsulation, cystic degeneration and hemorrhagic necrosis. Microscopically, the tumor resembled an islet cell tumor, but immunohistochemically there was no evidence of endocrinic activities. Ultrastructurally, tumor cells contain numerous mitochondria but no secretory or zymogen granules. This peculiar type of tumor usually arises in young women and shows a favorable prognosis. Diagnosis should be established immunohistochemically and ultrastructurally.
Using a synthetic common carboxy-terminal fragment of alpha-human atrial natriuretic polypeptide (alpha-hANP) and alpha-rat atrial natriuretic polypeptide (alpha-rANP), we have produced an antiserum for alpha-ANP(17-28) and established a radioimmunoassay (RIA) for alpha-ANP that recognizes alpha-hANP and alpha-rANP equally. High performance gel permeation chromatography coupled with the RIA revealed that alpha-hANP-like immunoreactivity (alpha-hANP-LI) in the human atrium consists of three major components, gamma-hANP, alpha-hANP and another. On the other hand, alpha-rANP-LI in the rat atrium comprised at least two components, 13K alpha-rANP-LI and 3K-5K alpha-rANP-LI, which were presumably gamma-rANP and beta-rANP, respectively. Thus, considerable amounts of gamma-hANP and gamma-rANP are present in human right auricles and rat atria, respectively. The RIA established in this study provides a useful tool to investigate the pathophysiological significance of alpha-ANP and related peptides in cardiovascular disorders and shows that gamma-ANP is not only a precursor of alpha-ANP but acts as an important hormone.
The opioid activity and opioid receptor type specificity of synthetic human leumorphin were studied in vitro. Human leumorphin inhibited the contraction of the myenteric plexus-longitudinal muscle preparation of the guinea pig ileum and was similar in opioid potency to porcine leumorphin. This action of human leumorphin was antagonized less effectively by naloxone than by the opiate antagonist Mr 2266. Human leumorphin also inhibited the contraction of the rabbit vas deferens which has only the kappa-type opioid receptor. It is concluded that human leumorphin has potent opioid activity and acts as an agonist at the kappa-type opioid receptor, like porcine leumorphin and other peptides derived from preproenkephalin B.
Porcine leumorphin, a putative opioid peptide corresponding to amino acid residues 228-256 of preproenkephalin B has been demonstrated to exist in the porcine neurointermediate pituitary. A recent study on the sequence analysis of genomic DNA of human preproenkephalin B has shown that human leumorphin differs in 3 amino acid residues from porcine leumorphin. In order to clarify whether leumorphin is an endogenous opioid peptide in man, we have studied its existence in the human brain using a radioimmunoassay and its opioid activity by a bioassay with the guinea-pig ileum myenteric plexus-longitudinal muscle preparation. High performance gel permeation chromatography and reverse-phase high performance liquid chromatography coupled with the radioimmunoassay for leumorphin have revealed that human leumorphin exists in water extracts of the human striatum. In the guinea-pig ileum assay, synthetic human leumorphin exhibited potent opioid activity, with the concentration of 3nM to give 50 per cent inhibition. These results indicate that leumorphin is a novel endogenous opioid peptide in man.
Soybean seeds (Glycine max) were grown in soil containing 10 ppm of benzo[a]pyrene (BaP). After 76 days growth, three kinds of quinones, namely BaP-1,6-, 3,6- and 6,12-quinones, were isolated and identified. However, the formative mechanism of the quinones in leaves has yet to be determined.
The reaction of a series of azapeptides with porcine pancreatic (PP) elastase and human leukocyte (HL) elastase has been studied and a series of new inhibitors and active site titrants were found for both PP elastase and HL elastase. Azapeptide p-nitrophenyl esters acylate both HL and PP elastase to form stable acylenzymes, which can be used for crystallographic studies. We have investigated the effect of a P1, P2, or P3 aza-amino acid residue on the reactivity of azapeptides with elastase. We have also studied the effect of changing the nature of the P1' leaving group and other portions of azapeptide structure. N-Acetyl-L-alanyl-L-alanyl-alpha-azaalanine p-nitrophenyl ester, N-acetyl-L-alanyl-L-alanyl-alpha-azanorleucine p-nitrophenyl ester, and N-acetyl-L-alanyl-L-alanyl-alpha-azanorvaline p-nitrophenyl ester are suitable titrants for either PP or HL elastase.
The organ culture of neonatal mouse calvaria produced both collagenase and collagenase inhibitor. The inhibitor was purified by a series of column chromatographies: DEAE-cellulose and CM-cellulose ion-exchange chromatography, concanavalin A-Sepharose and heparin-Sepharose affinity chromatography, and finally by Sephacryl S-200 gel filtration. The purified inhibitor migrated as a single band on sodium dodecyl sulfate-polyacrylamide gel electrophoresis and had a molecular mass of 28,000. The inhibitor was purified 140-fold to a specific activity of 163 units/mg with a yield of 18% over the first step of the purification by DEAE-cellulose chromatography. The inhibitor stained positively for carbohydrate with periodic acid-Schiff's reagent indicating, in conjunction with its affinity to concanavalin A, that the inhibitor is a glycoprotein. In addition to mouse bone collagenase, this inhibitor also inhibited chick bone, rat bone, rabbit corneal, and human gingival collagenase, but did not inhibit bacterial collagenase.
We treated a patient with a hyperfunctioning parathyroid cyst detected incidentally and which disappeared spontaneously. High levels of plasma PTH disappeared after removal of the cystic lesion of the parathyroid gland. Histologically, a secondary pseudocyst resulting from a cystic degeneration of an adenoma was observed. Minor hemorrhage of an unknown cause, within the adenoma, led to the large cystic lesion of the parathyroid gland.
The RNA of strains of rotavirus obtained from patients hospitalized with diarrhea during two winter epidemics of rotaviral infection in successive years (November 1981 through April 1982 and December 1982 through April 1983) was analyzed by polyacrylamide gel electrophoresis. A single dominant electropherotype was found during the first two or three months of each epidemic. In contrast, various electropherotypes were identified during the latter portion of each epidemic. RNA patterns of the rotaviral strains that were dominant during the early phase of the two epidemics were different from each other.
Evidence suggests that some of the effects of retinoids on sensitive target tissues are mediated by specific cellular binding proteins. This study demonstrated the presence of cellular retinoic acid-binding proteins (cRABP) in human skin. The approximate concentration and affinity of cRABP was determined independently in epidermal and sebaceous follicle cytosol, using both tritiated retinoic acid (RA) and tritiated 13-cis-retinoic acid (13-cis-RA) as radiolabeled ligands. Scatchard analysis suggested that on the basis of binding per mg of cytosol protein, the binding capacities by epidermal and sebaceous follicle cytosol were similar for RA and 13-cis-RA. However, the dissociation constants of binding of 13-cis-RA by sebaceous follicle cRABP was more than 9-fold the Kd for RA (1096 nM compared to 117 nM). The Kd for binding 13-cis-RA by epidermal cRABP was 31-fold the Kd for binding RA (3582 nM compared to 114 nM). Thus the affinity for 13-cis- RA by epidermal and sebaceous follicle cRABP is significantly less than for RA. It appears that the specificity of response of human sebaceous glands to 13-cis-RA is dependent on factors other than the concentration or affinity of cRABP in these structures.
The effect of a safflower margarine on hepatocarcinogenesis by N,N'-2, 7-fluorenylenebisacetamide was compared with that of safflower oil from which the margarine was made. A high-dextrin diet was used as a control for the two high-fat diets. The number of surviving mice in the margarine group at the end of the experiment was significantly lower compared with both the dextrin and the oil groups. A significantly high incidence of hepatic nodules type 2 was observed in the margarine group, whereas most liver tumors in both the dextrin and the safflower oil groups were of HN type 1 (p less than 0.05). Hepatocellular carcinomas were induced in some mice in all the groups. However, no statistical difference was found among the three dietary groups. Thus the difference in the types of the hepatic nodules among the three groups was not reflected in the incidence of hepatocellular carcinoma.
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To elucidate whether or not human phaeochromocytoma contains methionine-enkephalin-Arg6-Gly7-Leu8 (Met-enkephalin-Arg-Gly-Leu) and methionine-enkephalin-Arg6-Phe7 (Met-enkephalin-Arg-Phe) together with methionine-enkephalin (Met-enkephalin) and leucine-enkephalin (Leu-enkephalin), all of which are known to exist in the same precursor molecule (preproenkephalin A), we examined extracts from 16 phaeochromocytomas using high performance liquid chromatography (HPLC) and gel exclusion chromatography coupled with radioimmunoassays (RIAs) for these four opioid peptides. Met-enkephalin-Arg-Gly-Leu-like immunoreactivity (-LI) and Met-enkephalin-Arg-Phe-LI existed together with Met-enkephalin-LI and Leu-enkephalin-LI in 16 phaeochromocytomas. There was a wide variation in contents of Met-enkephalin-LI, Leu-enkephalin-LI, Met-enkephalin-Arg-Gly-Leu-LI and Met-enkephalin-Arg-Phe-LI. Significant positive correlations were observed among the contents of these four opioid peptides in 16 phaeochromocytomas. HPLC and gel exclusion chromatography followed by the RIAs showed the presence of Met-enkephalin, Leu-enkephalin, Met-enkephalin-Arg-Gly-Leu and Met-enkephalin-Arg-Phe together with their high molecular weight forms, which existed in variable amounts. Molar ratios of the contents of these four opioid peptides determined after HPLC varies from case to case. These results indicate the co-existence of Met-enkephalin, Leu-enkephalin, Met-enkephalin-Arg-Gly-Leu and Met-enkephalin-Arg-Phe in human phaeochromocytomas, suggesting the preservation of amino acid sequences of these four opioid peptides even in neoplastic tissues.(ABSTRACT TRUNCATED AT 250 WORDS)
Deepoxidation products P1, P2 and P3 of carbomycin A, deltamycin A1 and 4"-phenylacetyldeltamycin showed high in vitro antibacterial and antimycoplasmal activities which were comparable to those of the respective parent compounds. By contrast, the in vitro antimicrobial potencies of angolamycin P1 and rosamicin P1 were about ten-fold lower than those of the parent macrolides. In mice, the increase in the plasma levels of the epoxyenone macrolides due to deepoxidation was highly significant with the P1, P2 and P3 derivatives of carbomycin A and 4"-phenylacetyldeltamycin, whereas angolamycin P1 gave a moderately-improved plasma level compared with angolamycin.
The in vitro synergism of PS-5 combined with various penicillins and cephalosporins in antimicrobial activity was examined in detail against beta-lactam-resistant Gram-negative bacteria. PS-5 showed a highly significant synergism in antimicrobial action against Escherichia coli RGN238 in combination with penicillins; and against Proteus vulgaris GN76 and Serratia marcescens T55 in combination with cephalosporins. It was moderately synergistic against Citrobacter freundii GN346, Enterobacter cloacae 45, Proteus morganii 111 and Enterobacter aerogenes E19, whereas no synergism was observed against Pseudomonas aeruginosa E2 and Klebsiella pneumoniae 130.