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Biomedical subjects

Y Wada

Publications and source records attributed to Y Wada.

At least 217 records · Page 12Linked to original sources
PubMed2000

Intestinal spirochetosis in wild sika deer (Cervus nippon yesoensis) infected with Brachyspira species.

Seven adult free-ranging sika deer (Cervus nippon yesoensis) were examined by histology, immunohistochemistry and electron microscopy for intestinal spirochetal infection. Histologically epithelial and goblet cell hyperplasia and edema of the lamina propria mucosa with macrophage and lymphocyte infiltration were observed in the cecum and colon in 6 of the 7 deer. Numerous argyrophilic spirochetes were present in the crypts and some had invaded epithelial and goblet cells and caused degeneration. Immunohistochemically the organisms stained positively with polyclonal antisera against Brachyspira (Serpulina) hyodysenteriae and B. pilosicoli. Ultrastructurally they were 6-14 microm long, 0.2-0.3 microm wide and had 4-6 coils and 13 axial filaments per cell; such features were closely similar to those in the Brachyspira species. These results showed that the spirochetes were capable of inducing enteritis in deer and this intestinal spirochete infection might already be prevalent among wild sika deer in Japan. There is a possibility that this spirochetal colitis is a new syndrome in sika deer and that the same and/or similar spirochetes have infected ruminants, including sika deer and cattle.

Animals↗
PubMed2000

The prevalence of serum GB virus C/hepatitis G virus RNA and anti-E2 in Japanese children without a history of blood transfusion.

The prevalence of serum GB virus C (GBV-C)/Hepatitis G virus (HGV) RNA and anti-E2 was investigated in Japanese children younger than 16 years of age without a history of blood transfusion and the family members of serum GBV-C/HGV RNA-positive children. The prevalences of serum GBV-C/HGV RNA and anti-E2 were 0.5% (5/1000) and 0% (0/330), respectively. Viral RNA was also detected in the mothers of all five GBV-C/HGV RNA-positive children and in two of their siblings. Sequence determinations indicated the likelihood of mother-to-infant transmission in all cases. The presence of the virus persisted for at least 10-18 months in all 5 children, without any appearance of anti-E2.

Adolescent↗
PubMed2000

Screening for pyrimidine metabolism disorders using dried filter-paper urine samples: method development and a pilot study in Nagoya City, Japan.

A screening system for pyrimidine metabolism disorders by measurement with high-performance liquid chromatography using dried filter-paper urine samples is presented. This system permits the simultaneous determination of dihydrouracil, uracil, orotic acid and pseudouridine. The coefficient of variations for the four compounds on the filter-paper urine samples were 0.010 approximately 0.069 and the recoveries were 98.5 approximately 107.1%. The detection limits of the four compounds were 2 approximately 20 micromol/liter. The correlation between the filter-paper urine samples and liquid urine samples was excellent (0.938-0.988). We supeculated that this method could be used to detect pyrimidine metabolism disorders, such as dihydropyrimidinuria, dihydropyrimidine dehydrogenase deficiency and hereditary orotic aciduria. As a pilot study, we have analyzed dried filter-paper urine samples from 34, 200 healthy Japanese, and found three cases of dihydropyrimidinuria without clinical symptoms.

Drug Stability↗
PubMed2000

Detection rates of TT virus DNA in serum of umbilical cord blood, breast milk and saliva.

To date, the routes of mother-to-infant transmission of TT virus (TTV) have not been fully elucidated. The present study examines the detection rates of TTV DNA in the serum of pregnant Japanese women and in cord blood at the time of delivery, as well as in the saliva and breast milk of mothers one-month postpartum. Primers derived from the well-known translated region N22 (N22 system), as well as the untranslated region (UTR system) were used. The prevalence of TTV DNA in the serum of pregnant women was found to be 11.9% (19/160) using the N22 system and 72.4% (55/76) using the UTR system. No TTV DNA was detected in the cord blood samples (0/160) when the N22 system was used for detection but TTV DNA was detected in 11.8% (7/76) of samples studied with the UTR system. Using the N22 system, TTV DNA was not detected in breast milk, but was detected in saliva. However using the UTR system, TTV DNA was detected in both specimens. These results imply that some babies are vertically infected with TTV via cord blood at the time of delivery or via breast milk or saliva. However, further research is necessary to confirm this hypothesis. polymerase chain reaction; pregnant women; horizontal route of transmission

Adult↗
PubMed2000

TT virus infection in Japanese children: isolates from genotype 1 are overrepresented in patients with hepatic dysfunction of unknown etiology.

The pathogenecity of the TT virus (TTV) especially during childhood remains obscure. We investigated the prevalence of TTV in 40 patients with non-A to C hepatic dysfunction (non-A to C hepatic dysfunction group). Five patients with fulminant hepatitis of unknown etiology were enrolled in this group. We also examined 380 children without a history of transfusion or liver disease (control group). Subsequently, the genotypes of TTV strains isolated were analyzed in terms of their nucleotide sequences including 222 bp in the open reading frame 1 region. The prevalence of serum TTV DNA was 10/40 (25%) in the non-A to C hepatic dysfunction group and 25/380 (7%) in the control group. Sixty-six percent (23/35) of all examined cases exhibited either genotype 1 or 2. However, assessment of genotype in the non-A to C hepatic dysfunction group (10 cases) revealed a higher prevalence of genotype 1 than of all other genotypes (80% vs. 20%). This result differed significantly from that of the control group (25 cases; 32% vs. 68%). Such overrepresentation of genotype 1 suggests that this type of TTV strain is associated with the development of hepatic dysfunction of unknown etiology in Japanese children.

Adolescent↗
PubMed2000

Unique electroencephalographic change of acute encephalopathy in glutaric aciduria type 1.

We report the peculiar serial electroencephalographic (EEG) findings in a 7-year-old boy with glutaric aciduria type 1 during an episode of acute encephalopathy. The patient developed Reye-like syndrome triggered by cellulitis. Cranial magnetic resonance imaging demonstrated diffuse softening of cerebral hemisphere. The EEG on the day following onset of acute encephalopathy showed suppression burst pattern including continuous 14-15 Hz rhythmic waves at first. Then, periodic synchronous discharge appeared and lasted for about 40 minutes. Periodic synchronous discharge finally disappeared and nearly total electrocerebral silence continued. There have been no reports indicating such a change of EEG in a short period. The serial EEG changes probably reflect the process of electrical death of neurons in cerebral hemispheres.

Acute Disease↗
PubMed2000

Auto iris pigment epithelial cell transplantation in patients with age-related macular degeneration: short-term results.

Autologous iris pigment epithelial cell transplantation was performed on patients with exudative age-related macular degeneration (AMD). Autologous IPE cell culture was performed using autologous serum after iridectomy in 7 patients with AMD. The cell suspensions (2 approximately 20 x 10(4) cells) were transplanted into the submacular lesion of individuals after removal of neovascular membranes. Subsequent ophthalmological examinations, including best corrected visual acuity and fluorescein or indocyanine green angiography, were performed. In addition, 15 patients with AMD, who underwent removal of neovascular membrane without transplantation, were evaluated as non randomized controls. Varying degrees of atrophy or defects of choriocapillaris and retinal pigment epithelium were observed in all of the patients. No cystoid macular edema or fluorescein leakage was observed after treatment, but window defects were present. No patient had decreased visual acuity. One treated patient developed mild subretinal fibrosis and an other patient developed mild preretinal fibrosis, however no difference was significant when compared with the control. In conclusion, the treatment resulted in no significant improvement in macular function, as compared with the control; however, no rejection or deterioration in visual acuity occurred up to the 13 month follow up.

Aged↗
PubMed2000

Effects of a thyromimetic on apolipoprotein B-100 in rats.

We have studied the effects of a cardiac sparing thyromimetic, CGS 23425, on postprandial levels of triglycerides, abundance of apolipoprotein B (apo B) protein and hepatic apo B mRNA expression in rats. When compared with control rats, triglyceride clearance was significantly accelerated by treatment with CGS 23425. A full return to baseline values was achieved within 8 h after ingesting a large quantity of fat, as compared to >24 h in control animals. The abundance of apo B-100 protein in CGS 23425-treated hyperlipidemic rats decreased in a dose-dependent manner, but levels of apo B-48 were not significantly affected. Like L-tri-iodothyronine (L-T(3)), treatment with 30 microg/kg CGS 23425 for 6 or 9 days decreased the levels of apo B-100 protein by 80% and 40% respectively. This change was paralleled by a 27% reduction in hepatic apo B-100 mRNA. To investigate a potential mechanism of CGS 23425 action, we measured in vitro apo B mRNA editing activity in hepatocellular extract from control or CGS 23425-treated rats. Treatment with CGS 23425 increased activity of the hepatic apo B-100 editosome, apobec-1. In human hepatoma cells which lack apobec-1 activity, apo B-100 mRNA levels remained the same in cells treated with or without the agent. In summary, these observations show that CGS 23425 decreases the levels of apo B-100 in rats. This action of CGS 23425 involves apo B-100 mRNA editing activity.

APOBEC-1 Deaminase↗
PubMed2000

Coordinate regulation of matrix metalloproteinase-1 and tissue inhibitor of metalloproteinase-1 expression in human vascular smooth muscle cells.

The expression of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) by human vascular smooth muscle cells (SMC) was monitored as a function of the phenotypic modulation in vitro. Cell phenotype was manipulated by varying serum concentration and cell density. Synthetic phenotype was characterized by a minimum expression of the contractile proteins and a maximal proliferation rate. Contractile phenotype was quiescent and expressed a maximal level of contractile proteins. Synthetic cells expressed the highest levels of both MMP-1 and TIMP-1 and displayed maximal collagenolytic activity. No significant change was detected in MMP-2 expression or catalytic activity. Enzyme immunoassays revealed that MMP-1 expression fell by 77+/-2.4-95+/-0.5%, and that of TIMP-1 by 34+/-0.5-59+/-1.9%, as the cells acquired a contractile phenotype. The level of the MMP-1/TIMP-1 complex was similarly reduced by 78+/-2.9-85+/-1.6%. These data demonstrate that the expression of MMP-1 and TIMP-1 are coordinately regulated with SMC phenotype.

Adult↗
PubMed2000

Short communication: estimation of plasma osmolality from plasma electrolytes, glucose, and urea in calves.

Plasma osmolality estimated from plasma concentrations of Na+, Cl-, K+, glucose, and urea was compared with measured osmolality in preweaned Holstein calves. When calves (n = 5) were fed only milk replacer after fasting for 24 h, measured osmolality fluctuated almost in parallel with estimated osmolality during the 8-h period after feeding, although estimated values were about 90% of measured values. When calves (n = 5) were fed only calf starter after fasting for more than 16 h, measured osmolality did not parallel the estimated osmolality during the 8-h period after feeding. Some factors depressed measured osmolality in the first 2 h.

Animal Feed↗
PubMed2000

In vitro model of atherosclerosis using coculture of arterial wall cells and macrophage.

In order to determine the precise mechanism of the interactions between different types of cells, which are common phenomena in tissues and organs, the importance of coculture techniques are becoming increasingly important. In the area of cardiology, artificial arteries have been developed, based on the understanding of physiological communication of the arterial smooth muscle cells (SMC), endothelial cells (EC), and the extracellular matrix (ECM). In the study of atherosclerosis, the modification of low-density lipoprotein (LDL), which result in the recruitment and accumulation of white blood cells, especially, monocytes/macrophages, and foam cell formation, are hypothesized. Although there are well known animal models, an in vitro model of atherogenesis with a precisely known atherogenesis mechanism has not yet been developed. In this paper, an arterial wall reconstruction model using rabbit primary cultivated aortic SMCs and ECs, was shown. In addition, human peripheral monocytes were used and the transmigration of monocytes was observed by scanning electron and laser confocal microscopy. Monocyte differentiation into macrophages was shown by immunohistochemistry and comprehensive gene expression analysis. With the modified form of LDL, the macrophages were observed to accumulate lipids with a foamy appearance and differentiate into the foam cells in the ECM between the ECs and SMCs in the area of our coculture model.

Animals↗
PubMed2000

Decreased fluorouracil cytotoxic effect on EB-virus transformed lymphocytes from hereditary orotic aciduria.

5-Fluorouracil (5-FU), used widely for malignancies, phosphorylate mostly by uracil phosphoribosyl transferase (UPRT). Patients with hereditary orotic aciduria lack the orotate phosphoribosyl transferase (OPRT) activity. In the cancer cells, the OPRT activity is paralleled with the UPRT activity. This study shows that the UPRT activity of the hereditary orotic aciduria homozygote decreased about 40% of normal controls. Moreover, we investigated the 5-FU cytotoxic effects on hereditary orotic aciduria (one homozygote, 4 heterozygotes and 7 normal controls), using EB-virus transformed lymphocytes (EB-LC). 5-FU was addded to the culture medium at concentrations ranging from 0 to 10.0 micromol/l. The 5-FU cytotoxic effects on the homozygote were milder than those on controls at each 5-FU concentration. The 5-FU cytotoxic effects in the heterozygotes were at intermediate levels between the homozygote and controls. We speculate that 5-FU cytotoxic effects, both anti-tumor effects and adverse reactions, would be weak when a patient with hereditary orotic aciduria was treated with 5-FU.

Antimetabolites↗
PubMed2000

Detection of ornithine transcarbamylase deficiency heterozygotes by measuring of urinary uracil.

The importance of detecting heterozygosity for X-linked ornithine transcarbamylase deficiency is well known. Although the DNA analysis and the allopurinol loading tests are commonly used for this purpose, both methods require complicated procedures. In order to establish a simple test for detecting female heterozygotes, we examined the uracil and orotic acid in single-voided urine samples from 70 healthy women, and from 12 asymptomatic females with ornithine transcarbamylase deficiency. Based on the results of healthy women, we were able to determine a screening cut-off line of 11.9 micromol/mmol creatinine (mean +/- 1SD in logarithmic form) for uracil. Using this cut-off line, the sensitivity of OCT heterozygotes was 100%. We were also able to establish a second cut-off line of 28.9 micromol/mmol creatinine (mean +/- 3SD in logarithmic form) for diagnosis. Using this second cut-off line, the specificity of OCT heterozygotes was 100%. Our study has shown that the measurement of urinary uracil is a relatively simple and effective method for detecting female heterozygotes.

Female↗
PubMed2000

Genomic structure and mapping of human orphan receptor LXR alpha: upregulation of LXRa mRNA during monocyte to macrophage differentiation.

In order to identify changes in the gene expression profile during human monocyte/macrophage differentiation in the presence of GM-CSF, the expression level of various mRNA was studied using DNA microarray technology. We found LXR alpha (LXRa) to be the most highly induced transcriptional regulator during macrophage differentiation. The LXRa mRNA level was induced 40 fold which ranked it as the 10th highest among the approximately 5,600 genes studied. Although only restricted hepatic expression of LXRa mRNA had been reported, the macrophage expressed the highest level of LXRa among the nine human tissues and cultured cells studied. To further investigate transcriptional control, we have characterized the genomic structure of the human LXRa gene and determined the structure of its promoter region. The human LXRa gene consists of eleven exons, and analysis of the promoter region indicated the presence of conserved binding sites for myeloid zinc finger protein 1, which may be related to the extrahepatic expression of LXRa. LXRa is known to be activated by oxysterols, and the induced expression of the gene may be related to the foam cell formation in atherosclerotic lesions.

Base Sequence↗
PubMed2000

Gene expression induced by BO-653, probucol and BHQ in human endothelial cells.

2, 3-Dihydro-5-hydroxy-2, 2-dipentyl-4, 6-di-tert-butylbenzofuran (BO-653) and probucol, which act as radical scavenging antioxidants, were developed as anti-atherosclerotic medicines. In order to investigate the effect of these antioxidants on cell functions, we analyzed their ability to regulate gene expression in cultured human umbilical vein endothelial cells (HUVECs) using an oligonucleotide chip. Among 6,416 genes, 17 genes including those encoding mitochondrial proteins and proteins related to oxidative stress response were induced more than 3 fold by BO-653, probucol and tert-butylated hydroquinone (BHO). On the other hand, genes of three subunits of proteasome (PSMA2, PSMA3, PSMA4) were down-regulated by these antioxidants. A gene of cytochrome P-450 1A1 isozyme, a drug-metabolizing phase I enzyme, was expressed only by BHQ treatment. These results suggested that anti-atherogenic antioxidants affected gene expression in HUVECs by which they might regulate cell functions against oxidative stress.

Antioxidants↗
PubMed2000

The gene expression profile of human umbilical vein endothelial cells stimulated by tumor necrosis factor alpha using DNA microarray analysis.

Stimulation of vascular endothelial cells by tumor necrosis factor alpha (TNFalpha) plays a critical role in the pathogenesis of inflammation and vascular diseases. Changes in the gene expression profile in cultured human umbilical vein endothelial cells (HUVEC) treated with TNFalpha was analyzed with high-density oligonucleotide arrays comprised of 35,000 genes. TNFalpha stimulation profoundly induced genes involved in signal transduction, leukocyte adhesion and chemoattraction. ICAM-1 mRNA (fold change 111.9) was most profoundly induced followed by TNFalpha receptor-associated factor 1 (TRAF1) (95.5), Bcl3 (71.8), IL8 (65.4), fractalkaine (62.4), E-selectin (48.0), lymphotoxin beta (41.3) and VCAM-1 (31.7). In addition to these previously known genes, 18 poorly characterized or novel genes known as ESTs profoundly induced by TNFalpha. Initial sequencing analysis identified three of these the genes for squalene epoxydase, chromodomain helicase DNA binding protein 4, and CLP respectively. Further analysis of these genes will provide important information about TNFalpha signaling and function in vascular endothelial cells.

Cell Line↗
PubMed2000

A novel zinc finger protein mRNA in human umbilical vein endothelial cells is profoundly induced by tumor necrosis factor alpha.

Zinc finger proteins are known to mediate various transcriptional control mechanisms and other cellular functions in human cells. Tumor necrosis factor alpha (TNFalpha) induces a variety of genes in human endothelial cells including A20, an antiapoptotic zinc finger protein. In order to identify other zinc finger protein genes induced by TNFalpha, we studied the gene expression profile of human umbilical vein endothelial cells (HUVECs) stimulated by TNFalpha by means of oligonucleotide microarrays. Among the 155 genes encoding zinc finger motif, the level of EST M88357 mRNA encoding a novel designated EZFIT (endothelial zinc finger protein induced by TNFalpha) was induced most profoundly (>19 fold). The EZFIT gene is located on the chromosome 19q13.4. Isolation of the full length cDNA coding sequence by PCR using primers architected from the genomic sequence revealed that EZFIT has 490 amino acids which contain 13 C2H2 zinc finger motifs. Among 24 human organs and cell types studied, EZFIT mRNA was found to be most highly expressed in the placenta followed by the brain, testis, pancreas, heart, small intestine, muscle, uterus, prostate and peripheral blood leukocytes. EZFIT mRNA was not detected in the liver, lung, colon, stomach, the salivary gland or the thyroid gland.

Amino Acid Sequence↗