Biomedical subjects

S Masuda

Publications and source records attributed to S Masuda.

At least 307 records · Page 17Linked to original sources

PubMed1989

Improved methods for detection and serotyping of coagulase from Staphylococcus aureus.

Improved methods for detection and serotyping of staphylocoagulase were concomitantly devised. We devised an improved method for detection of coagulase activity on agarose film in the same manner as single radial immunodiffusion. The amounts of reagents required for detection of coagulase on agarose film were successfully diminished by adding polyethylene glycol (PEG) to the original formula described by Boothby et al. Using microplates in another improved method for coagulase serotyping, the amount of reaction fluid required was considerably less compared with the conventional tube method. PEG was found to be also effective to increase the efficacy of coagulase serotyping. In the presence or absence of anti-coagulase antisera, culture supernatants of staphylococcal strain grown in brain heart infusion broth were incubated with the reaction fluid containing bovine fibrinogen, rabbit plasma, 6-amino caproic acid, polyethylene glycol 6,000. Coagulase activity was visualized as a turbid mass formed in the wells. Turbid mass formation due to coagulase activity was type-specifically inhibited in the presence of type-specific antisera. Detailed procedures of the methods are precisely described with some preliminary results obtained by the methods.

Coagulase↗

PubMed1989

Altered virulence of a pleiotropic Staphylococcus aureus mutant with a low producibility of coagulase and other factors in mice.

The virulence of a pleiotropic Staphylococcus aureus mutant with an extremely low producibility of coagulase and other factors was investigated in mouse. A mutant strain, designated as CL-1, showed the same LD50 and the same intrarenal proliferation as its parental strain, when the mutant organisms were inoculated in mice in high doses. The mutant organisms, however, showed a diminished intrarenal proliferation compared with its parental organisms in low doses. This mutant strain expressed a pleiotropic phenotype such as a concomitant reduction in the producibility of coagulase, alpha-toxin, and Panton-Valentine leucocidin. The total effect due to the reduction in producibility of various factors on the virulence of the mutant strain was investigated with studies on the bacterial resistance to the phagocytic activity of leucocytes. A possible role of coagulase and that of some other staphylococcal exoproteins in the pathogenesis of S. aureus were discussed.

Animals↗

PubMed1989

Clear cell chondrosarcoma. A case report with topographic analysis.

A case of clear cell chondrosarcoma located in the right proximal end of the femur is presented. Radiologically, the tumor appeared as a large osteolytic lesion with mottled calcification resembling chondroblastoma. Histologically, the greater portion was made up of tumor cells with abundant clear cytoplasm and usually distinct boundaries, associated with areas of conventional chondrosarcoma. The proportion of the clear cell areas was about 60%, and they were mainly distributed along the tumor periphery. Moreover, myxoid chondrosarcoma-like areas, a feature not previously mentioned in clear cell chondrosarcoma, were observed, occupying about 10% of the tumor area.

Adult↗

PubMed1989

Binding position of phenylbutazone with bovine serum albumin determined by measuring nuclear magnetic resonance relaxation time.

The binding of phenylbutazone (PB) to bovine serum albumin (BSA) was considered to be predominantly due to hydrophobic interaction based on the thermodynamic parameters obtained by an equilibrium dialysis method. Little variation of proton nuclear magnetic resonance (1H-NMR) chemical shift of PB was found with change in the concentration of PB (0.5-5 mM) or upon the addition of BSA (7.25 x 10(-5) M). The NMR spectrum of PB in 0.1 M phosphate buffer solution at pH 7 showed that PB existed as a mesomeric anion. The spin-lattice relaxation time (T1) of PB was almost concentration-independent, but decreased in the presence of BSA to 36-38% for the phenyl group and 48-100% for the butyl group. The spin-spin relaxation time (T2) of PB was also almost independent of concentration, but was remarkably decreased in the presence of BSA to ca. 2.5% for the phenyl group and ca. 6-9% for the butyl group. The ratios of the spin-spin relaxation rate (1/T2) of the free PB to that of the bound PB were ca. 5000-11000 for the butyl group and ca. 23000 for the phenyl group. The binding of PB to BSA was considered to involve primarily the phenyl group.

Animals↗

PubMed1989

Bone marrow and serum concentrations of 25-hydroxyvitamin D, 24,25-dihydroxyvitamin D, and 1 alpha,25-dihydroxyvitamin D in patients with leukemia and normal subjects.

Concentrations of 25-hydroxyvitamin D (25-OH-D), 24,25-dihydroxyvitamin D [24,25(OH)2D], and 1 alpha,25-dihydroxyvitamin D [1,25(OH)2D] in bone marrow and serum of patients with leukemia and normal subjects were assayed. There were highly significant correlations between the bone marrow and serum concentrations of the respective vitamin D metabolites. Especially, the concentrations of 25-OH-D and 1,25(OH)2D in the bone marrow gave very similar values to those in serum. This is a big advantage in controlling the bone marrow levels of vitamin D metabolites in patients with leukemia, because doctors can calculate the bone marrow levels from the serum levels of the respective vitamin D metabolites without bone marrow aspiration. When 1 alpha-hydroxyvitamin D3 (1 alpha-OH-D3) was administered orally to eight patients with leukemia, clinical conditions were improved in seven patients: four complete remissions (CR), one partial response (PR), and two minor responses (MR) without severe hypercalcemia. The results suggest that the therapy with 1 alpha-OH-D3 is fairly effective for curing human leukemia although it is not dramatic.

Adult↗

PubMed1989

Concentrations of vitamin D-binding protein and vitamin D metabolites in plasma of patients with liver cirrhosis.

Plasma levels of vitamin D-binding protein (DBP) and vitamin D metabolites in patients with decompensated and compensated liver cirrhosis were assayed. Plasma levels of DBP in the decompensated group were significantly lower than those in the compensated group, but both were lower than the normal range. The plasma levels of 25-hydroxyvitamin D (25-OH-D) and 1 alpha,25-dihydroxyvitamin D [1,25(OH)2D] in the compensated group were within the respective normal ranges, whereas both values in the decompensated group were significantly lower than those in the compensated group. Most of 25-OH-D (higher than 96%) was confirmed to be circulated as a bound form with DBP in the plasma of not only the compensated but also the decompensated group. When vitamin D2 was given to the decompensated group, a significant increase of 1,25(OH)2D levels in the plasma could not be observed while 25-OH-D levels were increased. On the other hand, the administration of 1 alpha-hydroxyvitamin D3 (1 alpha-OH-D3) to the decompensated group caused a significant increase in the plasma levels of 1,25(OH)2D. Therefore, we suggest that the administration of 1 alpha-OH-D3 is useful for the treatment of bone disease induced by liver cirrhosis.

Calcifediol↗

PubMed1989

Changes in the concentrations of vitamin D and its metabolites in the plasma of healthy subjects orally given physiological doses of vitamin D2 by multivitamin or vitamin D preparations.

Changes in the concentrations of vitamin D and its metabolites in plasma of healthy subjects orally given physiological doses of vitamin D2 by multivitamin or vitamin D liquid preparations were determined and the bioavailability of vitamin D was studied. Separative assay on the D2 and D3 compounds of vitamin D, 25-hydroxyvitamin D (25-OH-D), 24R,25-dihydroxyvitamin D [24,25(OH)2D], and 1 alpha,25-dihydroxyvitamin D [1,25(OH)2D] was performed in plasma of eight healthy male volunteers. When the concentrations of vitamin D and its metabolites in plasma of volunteers were assayed after daily oral administration of 400 IU of vitamin D2 in a form of multivitamin tablet for 1 week, the variations of vitamin D3 and its metabolites in plasma levels were very small. In contrast, the concentrations of 25-OH-D2 and 1,25(OH)2D2 slightly increased after the administration, while neither vitamin D2 nor 24,25(OH)2D2 was detected. A single dose of 4,000 IU of vitamin D2 was orally given to the volunteers in a form of a vitamin D liquid preparation and the hourly variations were observed during 24 h. These concentrations of vitamin D2, 25-OH-D2, and 1,25(OH)2D2 were slightly higher than those of the repeated doses. The result suggests that even the high dose of 4,000 IU has little effect on the plasma levels of vitamin D2 and its metabolites by a single dose, indicating a low risk for hypervitaminosis D.

Administration, Oral↗

PubMed1989

Protein-binding properties of 22-oxa-1 alpha,25-dihydroxyvitamin D3, a synthetic analogue of 1 alpha,25-dihydroxyvitamin D3.

Protein binding properties of 22-oxa-1 alpha,25-dihydroxyvitamin D3 (22-oxa-1,25-D3), a synthetic analogue of 1 alpha,25-dihydroxyvitamin D3 (1,25-D3), were compared with those of vitamin D3 derivatives. The order of binding affinity to the chick embryonic intestinal receptor was 1,25-D3 greater than 22-oxa-1,25-D3 greater than 25-hydroxyvitamin D3 (25-D3) greater than 24R, 25-dihydroxyvitamin D3 (24, 25-D3) greater than vitamin D3 (D3), while that to the rat plasma vitamin D-binding protein (DBP) was 25-D3 greater than 24,25-D3 greater than D3 greater than 1,25-D3 greater than 22-oxa-1,25-D3. The binding potencies of 22-oxa-1,25-D3 to the receptor and DBP were about 1/8 and 1/600 of the respective values of 1,25-D3. When the distribution of the tritiated compounds in human plasma components was examined by an in vitro polyacrylamide gel electrophoretic method, [3H]-22-oxa-1,25-D3 was found to bind only to the lipoproteins including chyromicron. These results suggest that the replacement of a carbon atom into an oxygen atom in the side chain structure of 1,25-D3 results significant decrease in the binding affinity to DBP and that 22-oxa-1,25-D3 is transported as a complex-form not with DBP but with lipoprotein to the target tissues.

Animals↗

PubMed1989

[Electron microscopic study of glycoconjugate in nasal mucosa of nasal allergy by lectin histochemistry].

Glycoconjugates in glandular and goblet cells of nasal mucosa were compared between normal and nasal allergy by using various horseradish peroxidase (HRP)-conjugated lectins; WGA, PNA, UEA-I and RCA-I. Specific sugar residues of glycoconjugates could be identified under electron microscope. Golgi's complex of the serous secretory cells in nasal allergic mucosa had positive staining in UEA-I. Goblet cells of nasal allergic mucosa were stained strongly in PNA, compared to normal mucosa, however, they were stained weakly in WGA. In conclusion, glycoconjugates in glandular and goblet cells seem to be changed in nasal allergy.

Glycoconjugates↗

PubMed1989

[A case of thymoma associated with prostatic cancer].

A case of prostatic cancer treated with an LH-RH analogue depo-preparation was found to have a mediastinal thymoma which was later removed by surgery. The association of thymoma and prostatic cancer has not been documented in the world literature, and it remains to be elucidated whether the occurrence of the both tumors is a coincidence or etiologically inter-related.

Adenocarcinoma↗

PubMed1989

Adenomatoid tumor of the epididymis with special reference to immunohistochemical study of 3 cases.

Three cases of epididymal adenomatoid tumor are presented. The adenoid compositions of the tumors lined by epithelial cells showed a canalicular pattern with large vascular spaces, tubular pattern with glandlike regions or plexiform pattern with connective tissue strands. Immunohistochemistry demonstrated positive cytoplasmic staining for keratin, but negative for carcinoembryonic antigen and factor VIII-related antigen in each neoplastic tissue. These findings support the mesothelial origin of the epididymal adenomatoid tumors.

Adult↗

PubMed1989