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Biomedical subjects

R Ikeda

Publications and source records attributed to R Ikeda.

At least 109 records · Page 6Linked to original sources
PubMed1993

Characterization of a phenol oxidase from Cryptococcus neoformans var. neoformans.

In Cryptococcus neoformans, enzymic oxidation of various catechols leads to melanin, a proposed virulence factor. A phenol oxidase enzyme of Cryptococcus neoformans var. neoformans produced at 25 C has been purified from an ultracentrifugal supernatant of an extract of broken cells. Hydrophobic interaction chromatography followed by anion-exchange column chromatography allowed purification of the phenol oxidase. The molecular weight of the enzyme estimated by gel filtration was about 80,000 and a dimeric species (Mw = 160,000) was suggested. The isoelectric point of the protein was approximately 4.1. An NH2-terminal 31 amino acid sequence was determined using phenol oxidase electroblotted onto a PVDF membrane after nondenaturing gel electrophoresis. Upon searching the Peptide Institute (Osaka) data base, no proteins with high degrees of homology were found.

Amino Acid Sequence↗
PubMed1993

Evidence for interference by immune complexes in the serodiagnosis of cryptococcosis.

The latex agglutination test was used to compare cryptococcal antigen titers before and after protease treatment in 19 patients with pulmonary cryptococcosis. Antigen was detected by the LA test in 13 of 33 serum samples before protease treatment, and in an additional 13 samples following treatment. Of 26 antigen-positive serum samples, 22 (84.6%) showed an increased antigen titer after protease treatment. Using the cell slide agglutination test, antibody was detected in 3 of 19 cases. In one of these 3, antigen could only be detected after protease treatment. Soluble immune complex was prepared in vitro using anti-C. neoformans rabbit antiserum and polysaccharide antigen of C. neoformans, and the effects of immune complexes on the LA test were examined. In this experimental model, soluble immune complexes seemed to be observed in antibody excess region, because the antigen titers were increased after the protease treatment. We concluded that C. neoformans capsular polysaccharide antigen and anti-C. neoformans antibody formed soluble immune complexes in patients' sera, which interfered with antigen detection by the latex agglutination test without protease treatment.

Adult↗
PubMed1993

[A study on the pharmacological mechanism of the mood stabilizer--the changes of the rat brain concentrations of monoamines and their metabolites after the administration of Li, CBZ and VPA for 14 days].

The concentrations of monoamines and their metabolites (refer to Tables 1 and 2 about each material) in the rat whole brain except for the olfactory bulb and the pituitary gland were measured after the administration of lithium (Li), carbamazepine (CBZ) and valproic acid (VPA) for 14 days. The plasma levels of three drugs were each 0.96 +/- 0.21 mEq/L (Li), 14.216 +/- 3.78 micrograms/ml (CBZ) and 53.341 +/- 31.76 micrograms/ml (VPA). The brain concentrations of monoamines and their metabolites are shown on Tables 1 and 2, and their change rates of the administrated groups to the intact group as control on Figs. 1 and 2. Some changes were similar, i.e. tryptophan, 5-HT, 5-HIAA and L-DOPA seemed to increase, and normetanephrine and 3-MT seemed to decrease in common in three groups. On the contrary, tyrosine, 3-o-methyldopa, DOPAC and HVA increased significantly in only VPA group. It is an uncertain supposition that the common increases or decreases on this study may show the common mechanism among three mood stabilizers, but these changes are very interesting because many reports have mentioned the relation between mood disorder and monoamine neurotransmission. Especially, the common increases of tryptophan, 5-HT and 5-HIAA and the common decreases of 3-MT and normetanephrine may suggest some relation to the pharmacological mechanism of the mood stabilizer.

Animals↗
PubMed1993

[Isolated hypogastric artery aneurysm ruptured into urinary bladder: a case report].

An 81-year-old man was admitted to our hospital with a complaint of dysuria. He had had a right hypogastric aneurysm repaired three years earlier. Physical examination showed a distended soft abdomen and tender mass about the size of a child's head but no murmur was heard over the mass. An excretory urogram (DIP) showed left hydronephrosis and no excretion from the right kidney. Computerized tomography (CT) showed urinary bladder compressed by the mass on the upper right back side. Cystography showed that the large mass occupied the pelvic region with calcification and communicated with the bladder. After a few days, an operation for the aneurysm was undertaken by the surgical department. Although bilateral ureterolysis was possible, a resection of the aneurysm could not be done. The aneurysm was injected with fibrin adhesive and a bilateral nephrostomy was performed. The renal function has been stable and the size of the aneurysm has remained unchanged for 9 months after the surgery.

Aged↗
PubMed1993

[Renal cell carcinoma with contralateral adrenal metastasis: a case report].

A case of contralateral adrenal metastasis of renal cell carcinoma is reported. The patient was a 54-year-old male, who underwent a right radical transperitoneal nephrectomy for renal cell carcinoma, and had been administered interferon alpha intramuscularly. Nine months after the operation computerized tomography revealed the presence of an adrenal mass on the left side, undetected at nephrectomy, which suggested that the renal cell carcinoma had metastasized. A left adrenalectomy was performed. Histologically, the mass was identical to metastasis of renal cell carcinoma. The patient was administered supplementary hydrocortisone and was well 3 months after the adrenalectomy with no evidence of recurrence or other metastasis. This is the 24th case of contralateral adrenal metastasis of renal cell carcinoma in the Japanese literature.

Adrenal Gland Neoplasms↗
PubMed1992

Heterogeneity of phenol oxidases in Cryptococcus neoformans.

Phenol oxidase enzymes, linked to virulence in Cryptococcus neoformans, were prepared from broken cells. More enzyme activity was found in the ultracentrifugation supernatant; less was found in the membrane fraction. Phenol oxidases were located in acrylamide gel electropherograms by activity staining with L-dihydroxyphenylalanine (DOPA). Mobility differences between soluble and solubilized membrane-bound phenol oxidases were not found. Comparison of enzymes produced at 25 and 37 degrees C revealed that the enzyme had lower activity and lower mobility at 37 degrees C. The mobility of 25 degrees C phenol oxidases from strains of C. neoformans var. gattii was lower than that of those from C. neoformans var. neoformans. Half of the phenol oxidase produced at 25 degrees C was bound by concanavalin A, while that produced at 37 degrees C was not bound. However, glucose starvation of cultures at 25 degrees C overnight resulted in increased amounts of enzyme which did not bind to concanavalin A. A given strain of C. neoformans produces different species of phenol oxidase under different culture conditions.

Cryptococcus neoformans↗
PubMed1992

[Rat brain concentrations of monoamines and their metabolites after chronic administration of diazepam and tandospirone].

Tandospirone has been reported as a serotonergic antianxiety drug with a different pharmacological mechanism from benzodiazepines. In the present study, the brain concentrations of monoamines and their metabolites were measured, comparing control rats and two groups of rats which were given tandospirone (10 mg/kg, ip) and diazepam (5 mg/kg, ip) each for 14 days. After sacrifice, brains of all animals were cut and divided into three portions, i.e. the cortex (COR), cerebellum (CER) and subcortical structures and brain stem (SS & BS). The concentrations of COR and SS & BS were measured using a Neurochemicalanalyzer (NCA, ESA, Inc., USA) with a reverse-phase column (Neurocolumn, Niko Bioscience Inc.). In the COR, 3-O-MDOPA (3-O-methyldopa) increased in the tandospirone group. In the SS & BS, 3-O-MDOPA increased in the diazepam and tandospirone groups. 5HIAA (5-hydroxyindoleacetic acid), DOPAC (3,4-dihydroxyphenylacetic acid) and HVA (homovanillic acid) decreased in the tandospirone group.

Animals↗
PubMed1992

[Evaluation of diet of calcium stone patients].

To clarify the relationship between renal stone formation and the diet, the consumption of various nutrients of calcium stone formers was investigated. The study included 24 male and 12 female stone formers, between 20 and 78 years old (mean 42 years). The daily consumption of nutrients was compared to the daily nutritive requirement for the Japanese. The amounts of total and animal protein ingested by all the patients were significantly larger than the daily nutritive requirements. The animal protein ratio was also significantly higher. Concerning the total protein, animal protein and animal protein ratio, male and female patients showed similar results. Salt consumption was significantly larger for all the patients and the male patients than the daily nutritive requirement for the Japanese. Female stone formers also showed this tendency. Consumption of calcium and carbohydrate by all the patients and the male patients was significantly smaller than the daily nutritive requirement. This tendency was observed for the female patients.

Adult↗
PubMed1991

Comparison of serological and chemical characteristics of capsular polysaccharides of Cryptococcus neoformans var. neoformans serotype A and Cryptococcus albidus var. albidus.

The antigenic formula and chemical structure of capsular polysaccharide (CPS) of Cryptococcus albidus var. albidus (C. albidus) were studied in relation to those of C. neoformans var. neoformans serotype A (C. neoformans A). The results of slide agglutination tests with factor sera and reciprocal adsorption experiments showed that antigenic formula of C. albidus was the same as that of C. neoformans A. The soluble CPSs from the two species were obtained from culture supernatants by precipitation with ethanol followed by purification by chromatography on DEAE-cellulose column. The structural analyses of such CPSs from the two species showed that the antigenic CPS fractions consisted of a backbone of alpha(1-3)-linked D-mannopyranosyl residues with a single branch of beta(1-2)-xylose or glucuronic acid, and mostly with O-acetyl groups, in which side chains and O-acetyl groups were responsible for antigenic specificity. It was found that there was a minor difference between the CPS of C. neoformans A and that of C. albidus; in the former, unsubstituted mannose residues existed in a low frequency, but in the latter none. Moreover, the 1H-nuclear magnetic resonance spectra of partially hydrolyzed acidic fragments of the two CPSs indicated that two xylose side chains were present between glucuronic acid side chains. Taken together, it was suggested that these two species of C. neoformans A and C. albidus are closely related to each other in their CPSs.

Animals↗
PubMed1991

Evaluation of a new method for identification of Cryptococcus neoformans which uses serologic tests aided by selected biological tests.

A new method for identifying Cryptococcus neoformans isolates and their serotypes by the slide agglutination test using five kinds of factor sera, with the aid of nitrate reduction, phenol oxidase, and growth at 37 degrees C tests was evaluated by using 36 reference strains and 75 clinical isolates of C. neoformans. The results showed that the reference strains were identified exactly as they were labeled, and clinical isolates were identified as C. neoformans serotypes A, D, and AD. C. neoformans could be distinguished from other Cryptococcus species that cross-reacted with factor sera by their ability to grow at 37 degrees C. These results indicate that the slide agglutination test combined the use of factor sera for isolates which grow at 37 degrees C is a useful method for identification of C. neoformans and their serotypes and that the nitrate reduction test (negative in 100% of the isolates) and the phenol oxidase test (positive in approximately 95% of the isolates) can be used to confirm that the species is C. neoformans.

Agglutination Tests↗
PubMed1991

[Innervation of the sacroiliac joint. Macroscopical and histological studies].

Macroscopical and histological studies were carried out to clarify nerve innervation of the sacroiliac joint which is believed to have a role in the development of low back pain. Eighteen Japanese adult cadavers were used for gross anatomical examination and six for histological examination of the nerve supply to the joint. The results were as follows: 1) It is suggested by the gross examination that the upper ventral portion of the joint is mainly innervated by the ventral ramus of the 5th lumber nerve. 2) The lower ventral portion of the joint was mainly supplied by the ramus of the 2nd sacral nerve or branches from the sacral plexus. 3) Lateral branches of the dorsal ramus of the 5th lumber nerve were considered to be the main nerves which innervated the upper dorsal portion of the joint. 4) The lower dorsal portion was innervated by nerves arising from a plexus composed of lateral branches of the dorsal rami of the sacral nerves. 5) The nerves which innervate the joint range in diameter from 0.292 mm to 0.997 mm, and no difference was found among those in the four subdivisions of the joint. 6) Histological examination revealed that nerve fibers and the terminals were present in the joint capsule and adjoining ligaments. The nerve fibers varied from 0.2 micron to 2.5 microns in diameter and ended with five morphologically different terminals.

Adult↗
PubMed1991

A novel fibrinolytic enzyme extracted from the earthworm, Lumbricus rubellus.

A strong fibrinolytic enzyme was readily obtained in saline extracts of the earthworm, Lumbricus rubellus. It hydrolyzed not only plasminogen-rich fibrin plates, but also plasminogen-free fibrin plates. The average fibrinolytic activity was about 100 CU (plasmin units) or 250 IU (urokinase units)/g wet weight. The molecular weight and isoelectric point were about 20,000 and 3.4, respectively. The enzyme was heat-stable and displayed a very broad optimal pH range. DFP and SBTI strongly inhibited the enzyme, but the anti-plasmin agent, t-AMCHA, exerted little effect under the same conditions. Purification of the enzyme was performed and three partially purified fractions were obtained. These three fractions were further subdivided. The first fraction (F-I) was divided into three fractions (F-I-0, F-I-1, and F-I-2), which exhibited similar biochemical characteristics. The second fraction (F-II) could not be subdivided. The third fraction (F-III) was divided into two fractions (F-III-1 and F-III-2). Based on results for their enzymatic activities against various substrates, the fraction I enzymes are thought to represent a chymotrypsin-like enzyme and the fraction III enzymes to represent a trypsin-like enzyme. The fraction II enzyme appears to be neither a trypsin- or chymotrypsin-like enzyme nor an elastase. The amino acid compositions of the six enzymes were estimated. Compared with other serine enzymes, these enzymes contained very abundant asparagine or aspartic acid, and there was very little proline or lysine. From the above data, these enzymes are regarded as novel fibrinolytic enzymes, and we name them collectively as Lumbrokinase from the generic name of the earthworm.

Amino Acids↗
PubMed1991

[Renal carcinoma in hemodialysis patients. Specially concerned with acquired cyst].

Acquired cystic disease of the kidney (ACDK) with carcinoma in the original kidney is one sensational complication of long-term hemodialysis patients. The rate of incidence is about forty times higher than that in the general population and especially high in the young male group. From Dec. 1978 to Nov. 1990, we identified 8 patients of ACDK by computerized tomography (CT) scan, sonographic examination and angiography. Most patients had no clinical symptoms. The mean term of hemodialysis of the patients was 8 yrs. And one patient was diagnosed as having ACDK and tumor 8 yrs after kidney transplantation and then the kidney was removed. Their mean age was about 32 y.o. and the tumor size 1-3 cm in diameter. All tumors were inside the renal capsule. (Robson-1) Pathohistologically, the tumor area consisted of mainly clear cell carcinoma and the epithelium of the cyst wall showed multi-layered or papillary hyperplasia. In the 1st and 7th cases, simple nephrectomy was performed by transperitoneal approach. In the other cases it was performed by flank incision. All cases have had no recurrence and no metastasis of renal carcinoma. The etiology of ACDK and carcinoma occurrence has not been clarified yet, but it is suggested that uremic metabolite and deficiency of immuno-surveillance may cause the pathological changes in kidney tissue.

Adenocarcinoma↗
PubMed1991

[Technique and problems of total parathyroidectomy with autotransplantation in secondary hyperparathyroidism].

Between 1982 and 1990, 20 patients with chronic renal failure underwent total para-thyroidectomies and autotransplantations as treatment for secondary hyperparathyroidism. Fourteen cases were cured of their symptoms and their serum PTH levels was restored to normal. Recurrent hyperparathyroidism developed in 6 cases. In 3 of the 6 cases, excision of parathyroid tissue from the forearm could easily be performed under local anesthesia. Of the other cases, 2 had five and one had six glands. Several localizing methods should be performed before operation, in order to overlook the parathyroid glands in different anatomic positions.

Adult↗