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Biomedical subjects

R Ikeda

Publications and source records attributed to R Ikeda.

At least 91 records · Page 5Linked to original sources
PubMed1997

Damage attributable to extracorporeal shockwave lithotripsy and deposition of calcium oxalate crystals on ureteral stents.

Ureteral stents have been widely used during and after SWL depending on the size of the stones and the condition of the urinary tracts. The use of stents can help to reduce complications and contributes to stone passage. However, some reports note complications that were attributed to indwelling ureteral stents. We attended to the role of obstruction of ureteral stents in those complications. The aim of this study was to analyze factors that influence ureteral stent obstruction and damage caused by SWL. Crystal deposition and the damage by SWL were examined in all ureteral stents by the use of continuous flow system and were evaluated by scanning electron microscopy. The degree of crystal deposition and damage differed depending on the individual stent. The material properties of the stent surface are the major factor influencing crystal deposition and the degree of damage by SWL. The indications for ureteral stenting must be considered in each case, because the routine use of ureteral stents has a possibility to increase complications.

Calcium Oxalate↗
PubMed1997

Fatty acid compositions of colostrum, cord blood, maternal blood and major infant formulas in Japan.

Lipid profiles in colostrum, cord blood, maternal blood and major infant formulas in Japan were analyzed. In the first part of the study, colostrum obtained from 36 normal delivery women and six kinds of infant formulas provided by three major milk companies were analyzed for their fatty acid composition using capillary gas-lipid chromatography. Although enriched with docosahexaenoic acid (DHA), the percent composition of DHA in the six infant formulas (0.15-0.21%) was significantly lower than that in the colostrum (1.1 +/- 0.54). Arachidonic acid (AA) and eicosapentaenoic acid (EPA) were present in the colostrum but not detectable in the infant formulas. It is recommended that although the exact amount of specific fatty acids needed in the infant diet was not completely known, to be as close as possible to natural breast milk, the level of DHA, EPA and AA should be raised in the infant formulas. In the second part of the study, 19 pairs of maternal and cord blood were analyzed for their lipid profile. All samples were from normal vaginal delivery. The measurement of cholesterol, triglycerides, phospholipids and free fatty acids was performed with commercially available enzymatic methods on an automated discrete random access analyzer. Total fatty acid was determined as described in the first part of the study. The results were analyzed with Spearman's rank correlation coefficient. No correlation could be found between maternal and fetal concentrations of cholesterol, triglycerides, phospholipids or total fatty acids. Correlation could be found in non-esterified fatty acids, in palmitic acids, and oleic acid levels. It was concluded that the lipid transport and metabolism in the fetal-placenta unit is complex and further delicate investigation is required.

Adult↗
PubMed1997

Developmental changes in mucous cells of the early postnatal rat parotid gland: an ultrastructural and histochemical study.

Previous studies on the development of the parotid gland in various mammals have demonstrated that terminal clusters and acini contain mucous cells during the early postnatal period. However, little information has been available concerning the exact fate of the secretory granules in the mucous cells, specifically as to whether or not the mucous cells differentiate into serous cells. The present study aimed to determine the time of appearance of the mucous cells in the rat parotid gland as well as the morphological and histochemical changes of their granules. Light microscopy showed that cells positively stained with periodic-acid Schiff and alcian blue were sparsely distributed in the terminal clusters and acini on day 1 but had multiplied to a maximal level by day 5. They decreased in number on day 8 and were not recognizable at all by day 10. Electron microscopy revealed that the mucous cells initially contained granules of homogeneous low electron density, and then bipartite and tripartite granules with electron-dense cores were detected. By day 8 granules showing bipartite and tripartite structures and granules of homogeneous high electron density were seen to coexist in single cells. These observations suggest that mucous cells exist in parotid glands for a limited period of time and that, as the gland develops, the mucous granules come to resemble serous granules. Lectin histochemistry indicated that the secretory granules in the mucous cells were positive for peanut agglutinin, soybean agglutinin and wheat germ agglutinin, suggesting the occurrence of beta -D-galactose, alpha -D-N-acetyl galactosamine and beta -D-N-acetyl glucosamine which are the same sugar residues as those found in the granules of mature parotid serous cells. Immunostaining showed that even the low electron-dense granules in the mucous cells were weakly reactive for anti-rat parotid gland amylase; this reactivity gradually increased with development. These results suggest that mucous cell secretory granules which contain abundant glycoconjugate for a limited period during the development of the gland may change into serous granules.

Aging↗
PubMed1997

Expression of glutathione-peroxidase (GSH-PO) in the rat ventral prostate--effect of castration and administration of testosterone.

Immunolocalization of glutathione-peroxidase (GSH-PO), apoptosis and bcl-2 protein in the rat ventral prostate was investigated in the presence or absence of androgen. Male Sprague-Dawley rats were divided into four experimental groups. Group 1 consisted of intact controls. In group 2, rats were sacrificed two days after castration. In groups 3 and 4, rats were administered subcutaneously 1 mg/animal of testosterone-propionate daily for three or seven days at two days after castration. The intensity of GSH-PO staining in the glandular epithelial cells of the ventral prostate was remarkably decreased after castration (Group 2), and it clearly recovered when testosterone was administered (Groups 3 and 4) to the castrated rats. The prostatic GSH-PO mRNA levels were diminished in the castrated rat ventral prostate but greatly increased by testosterone (Groups 3 and 4). Furthermore, castration (Group 2) induced apoptosis in the prostatic glandular epithelial calls and the apoptosis was reduced by testosterone-administration (Groups 3 and 4) to the castrated rats. In groups 3 and 4, expression of bcl-2 protein was clearly detected in the glandular epithelial cells of the ventral prostate. These findings strongly suggested that expression of GSH-PO and bcl-2 protein in the glandular epithelial cells of the rat ventral prostate is testosterone-dependent.

Animals↗
PubMed1996

Dimethyl sulfoxide and related polar compounds enhance infection of human T cells with HIV-1 in vitro.

We observed the enhancing effect of dimethylsulfoxide (DMSO) on infection of human T cells with human immunodeficiency virus type 1 (HIV-1). Similar enhancing effects were also found in related polar chemicals such as dimethylformamide, hexamethylenebisacetamide, sodium butyrate and retinoic acid. In acute infection of the human MT-4 T cell line, DMSO at a concentration of 1% reduced the amounts of HIV-1 required to establish similar infection by one log. Furthermore, infection of peripheral blood lymphocytes with HIV-1 was also augmented several times by DMSO. HIV-1 production from persistently infected human T cell lines, but not monocytic cell lines, was enhanced by DMSO and related polar chemicals. DMSO enhanced transcription of HIV-1 RNA in persistently infected T cell lines, and the enhancing effect of DMSO on HIV-1 production was inhibited by staurosporine, a protein kinase inhibitor. These findings suggested that DMSO enhanced HIV-1 infection of T cells mainly at the step of transcription of viral RNA.

Acetamides↗
PubMed1996

Inhibition of human immunodeficiency virus type 1 infectivity by a new amine bellenamine.

Bellenamine, (R)-3,6-diamino-N-(aminomethyl)hexanamide (molecular weight 174), produced by Streptomyces nashvillensis, which has been reported to have weak antibacterial activity and to slightly enhance the immune response, showed potent activity against human immunodeficiency virus type 1 (HIV-1). Its mode of action was investigated. Bellenamine inhibited de novo infection of human T cells with HIV-1, at a 50% effective concentration (EC50) of 0.62 micrograms/ml (3.6 microM). Its 50% cytotoxic concentration (CC50) was over 2000 micrograms/ml (11.5 mM) and thus its cytotoxicity was quite low. When HIV-1-infected cells were treated with bellenamine or glycosylation inhibitors, they produced virus with reduced infectivity, and thus bellenamine inhibited the secondary spread of HIV-1 in vitro similarly to glycosylation inhibitors. However, bellenamine did not change the apparent molecular weights of env or gag proteins, unlike glycosylation inhibitors. Bellenamine showed no significant activity against virus adsorption, reverse transcriptase, viral protease or the glycosylation process. The antiviral mechanism of bellenamine remains to be examined further.

Antiviral Agents↗
PubMed1996

Serological characterization of Trichosporon cutaneum and related species.

Recent molecular biological, chemical, physiological and morphological studies indicate that Tri-chosporon cutaneum and related species should be reclassified. In this study, antigenic characteristics of the species were determined. The results of adsorption experiments revealed that there were at least three serological types: I, II and III. Specific factor sera I, II and III were prepared on the basis of adsorption experiments and isolates were serotyped by cell slide agglutination (CSA). Since the CSA test was difficult to read in some strains, the results of the CSA test were compared with the findings from an enzyme-linked immunosorbent assay (ELISA). For the ELISA, crude polysaccharide antigens prepared from the culture supernatant were used as the antigen. The types determined by ELISA correlated well with those determined by the CSA test. These data suggest that T. cutaneum and related species have at least three serological types, and that the typing can be done by either CSA or ELISA.

Agglutination Tests↗
PubMed1996

Production of agglutinating monoclonal antibody against antigen 8 specific for Cryptococcus neoformans serotype D.

A hybridoma (clone CRND-8) that produced agglutinating monoclonal antibody (MAb) against Cryptococcus neoformans serotype D was established by using a soluble capsular polysaccharide-keyhole limpet hemocyanin conjugate for immunization. The isotype was immunoglobulin M(kappa). Specificity was determined by cell slide agglutination and enzyme-linked immunosorbent assay (ELISA). In both tests, the MAb reacted to serotypes D and A-D but not to serotypes A, B, and C. Furthermore, the specificity of the MAb determined by ELISA was the same as that of polyclonal antibody factor serum (PAb factor) 8, which showed high-level reactivity with serotypes D and A-D. These results supported the deduced specificity of the PAb-based antigenic factor 8. A total of 15 isolates of serotypes D and A-D but no serotype A isolates reacted with the MAb in cell slide agglutination tests. CRND-8 MAb can be used in place of PAb factor 8 for serotyping C. neoformans isolates and for the analysis of the antigen 8 epitope.

Agglutination Tests↗
PubMed1996

Amount of pollen has an effect on the systemic and local levels of soluble ICAM-1 in patients with seasonal allergic rhinitis.

We investigated whether the amount of antigen has an effect on the systemic and local levels of soluble ICAM-1 (sICAM-1) in patients with pollinosis, and assessed its biologic significance. The levels of subjective symptoms and sICAM-1 in sera and nasal epithelial lining fluids (ELF) from 14 subjects with pollinosis (allergic group) and eight healthy subjects (control group) were measured from pre- to postseason in 1993 (total pollen count: 10,854/cm2) and 1994 (total pollen count: 415/cm2), and the results were compared with each other among the four groups. The levels of subjective symptoms and sICAM-1 in ELF from the allergic group significantly increased during the season in both 1993 and 1994. However, there was a significant difference (P < 0.01) between the levels of those in 1993 and those in 1994 during the season. The levels of sICAM-1 in sera from the allergic group were significantly upregulated during the seasons and postseasons only in 1993, and there was a significant difference (P < 0.05) between the levels in 1993 and those in 1994 during the postseason. We conclude that amount of pollen has an influence on the local and systemic levels of sICAM-1, as well as the scores of subjective symptoms, in patients with seasonal allergic rhinitis.

Adult↗
PubMed1996

Immunolocalization of glutathione-peroxidase (GSH-PO) in the rat ventral prostate: effects of castration and administration of testosterone.

Immunolocalization of glutathione-peroxidase (GSH-PO) in the rat ventral prostate was studied in the presence and absence of androgen. Male Sprague-Dawley rats were divided into four experimental groups. Group 1 consisted of intact controls. In group 2, rats were sacrificed two days after castration. In groups 3 and 4, rats were injected subcutaneously with 1 mg of testosterone-propionate daily, for three or seven days, beginning two days after castration. The intensity of GSH-PO staining in the glandular epithelial cells of the ventral prostate decreased after castration, but recovered following treatment with testosterone. Furthermore, the prostatic GSH-PO mRNA levels were diminished in the castrated rat ventral prostate but greatly increased by testosterone. These findings strongly suggest that the expression of GSH-PO in the glandular epithelial cells of the rat ventral prostate is dependent on testosterone.

Animals↗
PubMed1995

Bufotenine reconsidered as a diagnostic indicator of psychiatric disorders.

We have analyzed products of the serotonin-degradative pathway, in which both N-methylserotonin and bufotenine are formed in urine specimens of products with psychiatric disorders by three-dimensional HPLC with electrochemical detection. Bufotenine was detected in urine from all autistic patients with mental retardation and epilepsy (n = 18) and many autistic patients (32/47) with mental retardation. Bufotenine was detected in the urine of 15 of 18 patients with depression. Thirteen of 15 schizophrenic patients were also positive for bufotenine. N-methylserotonin was also detected in some cases of each disorder. Only two of 200 urine specimens from healthy controls were positive for bufotenine. Thus, the presence and levels of bufotenine might be useful and important markers of some psychiatric disorders.

Adult↗
PubMed1995

Hypoaminotransferasemia in patients undergoing long-term hemodialysis: clinical and biochemical appraisal.

BACKGROUND & AIMS: It has been reported that patients with chronic renal failure have low serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels as a result of vitamin B6 deficiency. Chronic hepatitis C is common among patients undergoing hemodialysis, and low aminotransferase levels cause diagnostic problems. The aim of this study was to determine the cause of hypoaminotransferasemia. METHODS: Serum levels of vitamin B6 and its coenzyme were reassessed in relation to AST and ALT levels in patients undergoing long-term hemodialysis using high-performance liquid chromatography. RESULTS: The mean (+/- SD) serum AST and ALT levels in 304 patients negative for hepatitis B surface antigen and anti-hepatitis C virus were 9.2 +/- 2.4 and 7.4 +/- 1.7 IU/L, respectively. In 556 normal adults, they were 22.7 +/- 5.4 and 18.0 +/- 4.0 IU/L, respectively (P < 0.001). Mean serum vitamin B6 and pyridoxal-5'-phosphate levels in patients undergoing dialysis were not reduced compared with the control, although occasionally patients had low levels. The AST and ALT assay reagents in Japan do not contain added pyridoxal-5'-phosphate; addition of pyridoxal-5'-phosphate (0.1 mmol/L) to the reagent significantly increased measurements to similar extents in both groups. CONCLUSIONS: Serum AST and ALT levels in patients undergoing dialysis are very low, but they are not a result of vitamin B6 deficiency. The upper normal limits of AST and ALT levels in patients undergoing dialysis should be reduced considerably, and these levels should be interpreted with caution in the diagnosis of liver disease.

Adult↗
PubMed1995

[Renal cell carcinoma and acquired cystic disease of the kidneys in patients on long-term hemodialysis].

Since the first report in 1977 by Dunnill et al., a substantial number of articles have been written concerning the complications of acquired cystic disease of the kidneys (ACDK) and renal cell carcinoma developing in the native kidneys of patients undergoing long-term hemodialysis. The incidence has been reported to be 35% to 95% of ACDK in patients undergoing long-term hemodialysis. In addition, renal cell carcinoma has been described in 4% to 7% of the ACDK. The etiology of ACDK and renal cell carcinoma in the native kidneys of patients undergoing long-term hemodialysis remains unresolved. Because ACDK and renal cell carcinoma are usually asymptomatic, several reports described the use of imaging studies in the native kidneys of patients undergoing long-term hemodialysis and suggest a variety of management schemes to screen or monitor the status of the native kidneys. Ultrasonography is the most common screening study, but CT scan is more sensitive. Both studies are necessary to diagnose ACDK and renal cell carcinoma in the native kidneys of patients. We review our 10 cases and the Japanese literature with particular attention to the diagnosis and treatment of patients with ACDK and renal cell carcinoma. Our findings were similar to those reported by others. Patients receiving dialysis treatment for more than three years should have a baseline radiologic examination of the kidneys so that subsequent problems can be more easily identified and evaluated. The best surgical treatment for patients with ACDK and renal cell carcinoma is simple nephrectomy by flank incision in order to prevent surgical side effects, for example postoperative bleeding.

Adult↗
PubMed1994

Characterization of insoluble macromolecular Sn(II) complex and its application to the 99mTc labeling of human serum albumin-bearing mercapto groups.

A chelating ion exchange resin containing aminophosphonic acid groups was used as a polymer matrix for the preparation of an insoluble macromolecular Sn(II)(R-Sn) complex. Sn(II), which strongly bound to the surface of the polymer matrix by chelation, retained the ability to reduce 99mTc in the R-Sn complex. Human serum albumin-bearing-mercapto groups (HMA) was labeled with 99mTc at pH 2-3 using the R-Sn complex or SnCl2 as reducing agent. The 99mTc-HMA labeled with the R-Sn complex resulted in a higher sustained level of radioactivity in the blood of mice than the 99mTc-HMA labeled with SnCl2. These results suggest that the use of the R-Sn complex minimized Sn(II) contamination of the 99mTc labeling solution and can be used effectively as a reducing agent for 99mTc labeling of proteins containing sulfhydryl groups.

Animals↗
PubMed1994

[Determination of serum vitamin B12 and folic acid by non boil (new standard) radioassay].

On purpose to study the radioassay of serum vitamin B12 and folic acid using non boil methods in with these two vitamins were released from their endogenous binding proteins with alkaline denaturation and separated the bound vitamins from the free ones with the magnetic iron particles coated these vitamin binders (purified hog intrinsic factor and beta-lactoglobulin from cow milk) were evaluated on precision and accuracy, compared with boil radioassay. 1. The reproducibilities of non boil method were 4.5 +/- 2.5% on vit. B12 and 3.5 +/- 0.2% on folate (n = 10), respectively. 2. The recovery test of the two serum vitamins with the use of cyanocobalamin and pteroylglutamic acid (J.P.) were finely showed the rations of 95.2-99.0% for vit. B12 and 101.0-108.0% for folic acid. And that of folic acid use of 5-methyl-tetrahydro-pteroylglutamic acid was showed the ratios of 101.0-104.0%. The values of folic acid measured by this method were found slightly higher than non boil method using conventional standard. 3. The correlation coefficient between non boil method and boil method were 0.987 and regression equation was showed y = 0.97x + 73.59 for vit. B12 (n = 75) and r = 0.932, y = 1.02x-0.08 (n = 78) for folic acid. 4. Normal range of serum total vit. B12 concentration was 210-920 (484 +/- 160 pg/ml, n = 259) and that of folic acid was 2.5-9.2 (5.2 +/- 1.4 ng/ml, n = 257), as well as boil method. 5. Accordingly it was considered that non boil (new standard) method was excellent for estimation of vitamin B12 and folic acid clinical status.

Female↗
PubMed1993

Nucleotide sequence of tobamovirus Ob which can spread systemically in N gene tobacco.

The genomic RNA sequence of tobamovirus Ob (Ob), which can spread systemically in tobacco carrying the N gene, was determined. It consists of 6507 nucleotides and contains four open reading frames, exactly corresponding to the genomic organization of tobamoviruses known so far, i.e. encoding the 130K, 180K, 30K and coat proteins. There were no nucleotide overlaps between any open reading frames. The Ob nucleic acid sequence, predicted protein sequences and gene organization were compared with those of other tobamoviruses reported previously. This virus was originally reported as a tomato mosaic virus; however, the nucleotide sequence data given here refute this classification. The determinants that allow tobamovirus Ob to overcome the N gene, a feature peculiar to this virus, were not identified apart from sequence data. This virus should be regarded as a new tobamovirus. The determinants interacting with the tentative N gene product have not yet been analysed.

Amino Acid Sequence↗