Biomedical subjects

Y Ban

Publications and source records attributed to Y Ban.

At least 91 records · Page 5Linked to original sources

PubMed2001

Collaborative study on rat sperm motion analysis using CellSoft Series 4000 semen analyzer.

A collaborative study was conducted to determine useful and sensitive rat sperm motion parameters in a CellSoft Series 4000 semen analyzer to detect the effects of compounds on sperm motion. The effects on the sperm motion parameters were investigated using alpha-chlorohydrin, boric acid, ethinylestradiol, ethyl methanesulfonate, nitrazepam, nitrobenzene, ornidazole, sulfasalazine or valproic acid which are well known to induce reproductive or testicular toxicities. All compounds used in this study decreased percentage of motile sperm (% motile). Curvilinear velocity (VCL), maximum and mean amplitude of lateral head displacement (ALH max and ALH mean) were decreased by treatment with all compounds except for valproic acid. Treatment with alpha-chlorohydrin, ornidazole or sulfasalazine under mid-dosage regimens decreased only these parameters. Beat cross frequency (BCF) was increased by treatment with sulfasalazine. There were some treatments which caused either decreased or increased changes irrespective of dosage regimen in linearity, average radius, percentage of circular-swimming sperm out of motile sperm (circular/motile) and percentage of circular-swimming sperm out of all sperm (circular/all). Based on these results, we concluded that % motile, VCL, ALH max and ALH mean are considered useful and sensitive parameters for evaluating the effects of compounds on sperm motion. A parameter of BCF can be useful to detect the effects of specific compounds on sperm motion. Linearity, average radius, circular/motile and circular/all are not considered useful or sensitive indicators to detect the effects of compounds on sperm motion.

Animals↗

PubMed2001

Three Japanese patients from two families with generalized resistance to thyroid hormone with mutations in exon 9 of the thyroid hormone receptor beta gene.

Resistance to thyroid hormone (RTH) is a genetic disorder caused by mutations in the thyroid hormone receptor (TR) beta gene. The mutations are clustered in two regions: exon 9 and exon 10. To date, only one patient with an exon 9 mutation has been reported in Japan. We herein report three patients from two Japanese families with RTH and mutations in exon 9. A 52-year-old woman and her 18-year-old daughter, both with inappropriate secretion of TSH (SITSH) were diagnosed simultaneously with generalized RTH. Molecular analysis revealed a G345D mutation. An 11-year-old girl with SITSH, whose only manifestation was a goiter, had an R338W mutation, which is frequently associated with pituitary RTH. Thus, RTH with mutations in exon 9 of the TR beta gene is not so rare in Japan.

Adolescent↗

PubMed2001

No association of type 1 diabetes with a microsatellite marker for CTLA-4 in a Japanese population.

Susceptibility to insulin-dependent (type 1) diabetes mellitus is determined by both environmental and genetic factors. The primary gene associated with predisposition to type 1 diabetes is the human leukocyte antigen (HLA) class II gene (IDDM1). Recent studies have described linkage and association of type 1 diabetes to the cytotoxic T lymphocyte antigen-4 (CTLA-4) gene (IDDM12)in Caucasians. CTLA-4 is a candidate gene for T-cell-mediated autoimmune diseases because it is a negative regulator of T-cell proliferation. We investigated distribution of a CTLA-4 (AT)n microsatellite marker in 118 Japanese patients with type 1 diabetes and 195 control subjects. We also investigated association between this CTLA-4 gene polymorphism and GAD65 antibody positivity in 103 of the patients. CTLA-4 microsatellite marker loci were determined by polymerase chain reaction amplification of genomic DNA and resolution of the products on sequencing gels. GAD65 antibody was detected by radioligand binding assay. There was no significant difference in the distribution of CTLA-4 alleles between patients and controls, and no difference was observed in the prevalence of CTLA-4 alleles when GAD65 antibody-positive and -negative individuals with the type 1 diabetes were compared. The present study did not support an association between the CTLA-4 microsatellite marker and type 1 diabetes in our Japanese study population.

Abatacept↗

PubMed2001

[Primary adenocarcinoma of the renal pelvis with a pyeloduodenal fistula: a case report].

A 62-year-old woman visited our hospital complaining of fever and right flank pain. On excretory pyelography the right kidney containing three renal stones was not visualized. Retrograde pyelography revealed an irregular filling defect in the right renal pelvis. Computed tomography revealed renal stones and a tumor mass in the right renal pelvis. From these findings, the pelvic tumor of the right kidney complicated by renal stones was diagnosed. Right nephrectomy was performed. Because a fistula between the renal pelvis and the second portion of the duodenum was found in the operation, partial resection of the duodenum was also performed. Pathological diagnosis was adenocarcinoma of the renal pelvis and pyeloduodenal fistula due to chronic pyelonephritis. Postoperative chemotherapy was not given. This is the first case report of adinocarcinoma of the renal pelvis coexisting with a pyeloduodenal fistula.

Adenocarcinoma↗

PubMed2000

Estrogen receptor alpha dinucleotide repeat polymorphism in Japanese patients with autoimmune thyroid diseases.

BACKGROUND: The autoimmune thyroid diseases (AITDs), comprising Graves' disease (GD) and Hashimoto's thyroiditis (HT), appear to develop as a result of complex interactions between predisposing genes and environmental triggers. Susceptibility to AITDs is conferred by genes in the human leukocyte antigen (HLA) and genes unlinked to HLA, including the CTLA-4 gene. Recently, an association to some estrogen receptor (ER)alpha genotypes with breast cancer, hypertension, osteoporosis, generalized osteoarthritis, and some autoimmune diseases such as rheumatoid arthritis has been reported. We have analyzed a dinucleotide (TA)n repeat polymorphism lying upstream of the human ERalpha gene in patients with AITDs and in normal subjects. RESULTS: Seventeen different alleles were found in 130 patients with GD, 93 patients with HT, and 190 control subjects. There was no significant difference in the distributions of ERalpha alleles between patients and controls. CONCLUSIONS: The present results do not support an association between the ERalpha gene and AITD in the Japanese population.

Journal Article↗

PubMed2000

Regulation of glucose transporters during development of the retinal pigment epithelium.

The retinal pigment epithelium (RPE) separates the outer retina from its blood supply. To satisfy the retina's large requirement for glucose, the RPE expresses high levels of glucose transporters. In most rat cells, the transporter GLUT3 provides a basal level of transport, but the expression of GLUT1 can be regulated. The opposite is true in chicken (P. Wagstaff, H.Y. Kang, D. Mylott, P.J. Robbins, M.K. White, Characterization of the avian GLUT1 glucose transporter: differential regulation of GLUT1 and GLUT3 in chicken embryo fibroblasts, Mol. Biol. Cell 6 (1995) 1575-1589). We examined chick RPE to determine which isoform is regulated during development, and if the neural retina regulates GLUT expression. By RT-PCR, RPE expressed GLUT1 and GLUT3, but not GLUT2. Only the level of GLUT1 increased between E5 and E18. A corresponding increase in GLUT1 protein was observed by immunoblotting. Most of the increase occurred between E14 and E18, which corresponds to the late stage of tight junction development. A culture model of development was used to examine the intermediate phase, which extends from E7 to E14. While medium conditioned by the neural retina decreased paracellular diffusion across the tight junctions, it increased diffusion through the glucose transporters. Unlike mammals, chick upregulates different isoforms in quiescent RPE and proliferating fibroblasts. Further, the upregulation of glucose transport is coordinated with the development of tight junctions in the blood-retinal barrier.

Animals↗

PubMed2000

Two secreted retinal factors regulate different stages of development of the outer blood-retinal barrier.

The retinal pigment epithelium (RPE) lies at the interface between the neural retina and the choriocapillaries where it forms a blood-retinal barrier. Like endothelial regions of the blood-brain barrier, the development of the RPE barrier is a gradual, multistep process. A culture model of chick RPE was used to study this development. The permeability of the tight junctions that limit diffusion between neighboring RPE cells was measured as the transepithelial electrical resistance (TER). Embryonic day 14 (E14) retinas were used to make a conditioned medium that lowered the permeability of cultured RPE. The TER of cultures prepared from E14 RPE was twice that of E7 RPE. In each culture, retinal conditioned medium increases the TER 2-2.5 fold. The active factors of conditioned medium that affected each culture had different physical properties. The factor that affected E7 was protease-resistant with a Mr<10 kDa, but the factor that affected E14 appeared to be a protein of approximately 49 kDa. Unlike the effect of astrocyte conditioned medium on endothelia, retinal conditioned medium did not act synergistically with cAMP. These data indicate that the chick retina, which lacks astrocytes, uses different diffusible factors to regulate different stages of tight junction development.

Adrenergic Agonists↗

PubMed2000

Vitamin D receptor initiation codon polymorphism in Japanese patients with Graves' disease.

Recent studies have shown that related genetic influences on bone mineral density (BMD) and bone turnover are related to allelic variations in the vitamin D receptor (VDR) gene. Osteoporosis as a complication of hyperthyroidism is characterized by increased rates of both bone formation and bone resorption. In addition, VDR gene polymorphism influences susceptibility to some autoimmune diseases such as insulin-dependent diabetes mellitus (IDDM) and multiple sclerosis (MS). In the gene encoding the VDR, we investigated the distribution of a VDR-FokI polymorphism that changes the predicted protein sequence. The subjects were 131 female Japanese patients with Graves' disease and 150 female controls. The distribution of genotype frequencies differs between Graves' disease and controls (chi2 = 5.99, degrees of freedom = 2, p = 0.0386). We found overexpression of F allele (69% vs. 61%, p = 0.0472) and homozygote FF (48% vs. 33%, p = 0.0118) in Graves' disease patients compared with controls. We also correlated a VDR-FokI polymorphism with BMD in the distal radius and biochemical markers of bone turnover in patients with Graves' disease in remission. Although generally no significant association was seen between age-adjusted BMD and genotype, patients in remission for >5 years showed significantly lower age-adjusted BMD in Ff heterozygotes than in ff homozygotes (Z = 1.14 ff vs. Z = -0.43 Ff, p < 0.05). Moreover, serum concentrations of bone alkaline phosphatase were significantly greater in Ff homozygotes than in FF homozygotes (78 +/- 12 vs. 59 +/- 10, p < 0.05). The genotypes did not differ in serum concentrations of osteocalcin, urinary hydroxyproline, or urinary deoxypyridinoline. Our results indicate, for the first time, an association between Graves' disease and a VDR polymorphism in the Japanese and suggest that a VDR-FokI polymorphism may affect bone mineral metabolism and can predict risk of osteoporosis as a complication of Graves' disease in patients in remission.

Adult↗

PubMed2000

Vitamin D receptor initiation codon polymorphism in Japanese patients with Graves' disease.

Recent studies have shown that related genetic influences on bone mineral density (BMD) and bone turnover are related to allelic variations in the vitamin D receptor (VDR) gene. Osteoporosis as a complication of hyperthyroidism is characterized by increased rates of both bone formation and bone resorption. In addition, VDR gene polymorphism influences susceptibility to some autoimmune diseases such as insulin-dependent diabetes mellitus (IDDM) and multiple sclerosis (MS). In the gene encoding the VDR, we investigated the distribution of a VDR-FokI polymorphism that changes the predicted protein sequence. The subjects were 131 female Japanese patients with Graves' disease and 150 female controls. The distribution of genotype frequencies differs between Graves' disease and controls (chi2 = 5.99, degrees of freedom = 2, p = 0.0386). We found overexpression of F allele (69% vs. 61%, p = 0.0472) and homozygote FF (48% vs. 33%, p = 0.0118) in Graves' disease patients compared with controls. We also correlated a VDR-FokI polymorphism with BMD in the distal radius and biochemical markers of bone turnover in patients with Graves' disease in remission. Although generally, no significant association was seen between age-adjusted BMD and genotype, patients in remission for fewer than 5 years showed significantly lower age-adjusted BMD in Ff heterozygotes than in ff homozygotes (z = 1.14 ff vs. z = -0.43 Ff, p < 0.05). Moreover, serum concentrations of bone alkaline phosphatase were significantly greater in Ff homozygotes than in FF homozygotes (78 +/- 12 vs. 59 +/- 10, p < 0.05). The genotypes did not differ in serum concentrations of osteocalcin, urinary hydroxyproline, or urinary deoxypyridinoline. Our results indicate, for the first time, an association between Graves' disease and a VDR polymorphism in the Japanese and suggest that a VDR-FokI polymorphism may affect bone mineral metabolism and can predict risk of osteoporosis as a complication of Graves' disease in patients in remission.

Adult↗

PubMed2000

Differential regulation of tight junction permeability during development of the retinal pigment epithelium.

The retinal pigment epithelium (RPE) is an epithelial region of the blood-brain barrier. During embryogenesis, permeability of the barrier gradually decreases. A culture model of RPE development revealed differences in how tight junctions regulate the paracellular diffusion of ionic and nonionic solutes (Ban Y and Rizzolo LJ. Mol Vis 3: 18, 1997). To examine these differences, the permeation of ionic and nonionic monosaccharides was compared with mannitol, and the permeation of the alkali metals was compared with sodium. The order of permeation was 3-O-methlyglucose = glucosamine = mannitol > N-acetylneuraminic acid. The ratio of N-acetylneuraminic acid to mannitol permeability decreased with embryonic age of the RPE or exposure to retinal-conditioned medium. Neither the ratio nor the permeability was affected by inhibiting transcytosis. The ratio increased if tight junctions were disrupted in low-calcium medium. The permeation of cations followed the sequence cesium > rubidium > potassium = sodium > lithium and was unaffected by embryonic age or retinal-conditioned medium. These results are considered in terms of a model in which the size distribution, charge, or number of open junctional pores could be modulated. It suggests that different subpopulations of pores can be regulated independently during development.

Animals↗

PubMed2000

Vitamin D receptor gene polymorphism is associated with Graves' disease in the Japanese population.

Susceptibility to Graves' disease (GD), which is determined by environmental and genetic factors, is conferred by genes in the human leukocyte antigen (HLA) and genes unlinked to HLA, including the CTLA-4 gene. We recently described the association of GD with the vitamin D receptor (VDR) exon 2 initiation codon (VDR-FOK:I) polymorphism. An association of some VDR genotypes with osteoporosis, primary hyperparathyroidism, and some autoimmune diseases, such as insulin-dependent diabetes mellitus and multiple sclerosis, has been reported. We investigated the distribution of VDR gene polymorphism in 180 Japanese patients with GD (48 males and 132 females) and 195 controls (67 males and 128 females). A VDR allelic polymorphism was assessed by BSM:I endonuclease restriction after specific PCR amplification. Genotypic polymorphism was clearly defined as BB (no restriction site on both alleles), bb (restriction site on both alleles), or Bb (heterozygous). The distribution of genotype frequencies differed between patients with GD and controls (chi(2) = 7.53; 2 degrees of freedom; P: = 0.023). The relative risk conferred by at least 1 B allele (BB or Bb) was 1.5. We also found an association between VDR-APA:I polymorphism and GD. No relation was detected between this polymorphism and the VDR-FOK:I polymorphism in the patients. The present results support the association of the VDR gene with GD in Japanese by showing that the VDR gene could be a non-HLA-linked gene predisposing an individual to GD. The role of the VDR gene polymorphism should be further studied in other populations, and the distribution of other polymorphisms, such as the polyadenylase polymorphism further down the VDR 3'-untranslated region, should be studied in terms of GD susceptibility.

Aged↗

PubMed2000

Beneficial application of quantitative coronary angiography (edge detection algorithm) in analysis of dissected coronary arteries to predict long-term patency.

The present study evaluated the application of quantitative coronary angiography (edge detection algorithm) for the analysis of coronary dissection lesions after balloon angioplasty. Acute and late results were obtained by the edge detection algorithm in 60 patients with 66 dissected lesions (NHLBI types B-C). The edge detection algorithm delineated the border of the true lumen in 32 lesions (group with automated analysis alone, 48.5%) and included the dissection cap in the analysis in 34 lesions in which manual editing was adjuncted (group with manual editing, 51.5%). In both groups, the minimal lumen diameter after balloon angioplasty obtained by initial automated analysis was correlated to that obtained at the 5.3-month follow-up similarly (r=0.554, p=0.0010 for the group with automated analysis alone and r=0.613, p=0.0001 after automated analysis for the group with manual editing). However, additional manual editing reduced the correlation coefficient (r=0.240, p=0.1707) in the latter group. Thus, in terms of predicting long-term patency, it is reasonable to let the edge detection algorithm decide the measurements in types B and C dissected lesions.

Algorithms↗

PubMed2000

cDNA cloning and molecular analysis of papaya small GTP-binding protein, pgp1.

In the course of papaya EST collection, one clone (pRA4-3) encoding partial sequence of papaya small GTP-binding protein gene, pgp1, was obtained. Based on the sequence information of pRA4-3, the entire coding region of pgp1 was cloned using the 3'RACE PCR technique. ORF of pgp1 is 636bp long and deduced molecular weight of the protein is 23,311. Phylogenetic analysis showed that PGP1 belongs to YPT/RAB group of the small GTP-binding protein and is a homologue of RAB2. Southern analysis showed that there are several pgp1-related genes in papaya genome. Northern analysis showed that pgp1 was expressed equally in stems of seedlings that were grown under light and dark conditions. This result shows that PGP1 is not involved in the phytochrome-mediated signal transduction as an auxin signal transducer in stems of papaya seedlings.

Amino Acid Sequence↗

PubMed2000

Aberrant luteinizing hormone-releasing hormone-stimulated adrenocorticotropic hormone secretion in a patient with pituitary hyperplasia due to primary hypothyroidism.

We report a patient with primary hypothyroidism associated with an aberrant ACTH response to the LH-RH test. A 40-year-old woman was admitted to our hospital displaying headache, nausea, and numbness on the left side of her face, upper limbs, and tips of her toes. Computed tomography and magnetic resonance imaging revealed a mass-like lesion in the pituitary. A high serum TSH concentration with concomitant low thyroid hormone concentrations resulted in a diagnosis of primary hypothyroidism. To exclude the possibility of a coexisting pituitary tumor including a TSH-secreting tumor, we performed dynamic TSH secretion tests. TRH testing showed an excessive, delayed TSH response, typical of primary hypothyroidism. Serum TSH decreased not only after administration of CRH, octreotide, or L-DOPA, but also after administration of LH-RH. In this case, LH-RH testing induced ACTH secretion. To determine if aberrant ACTH secretion in response to LH-RH loading is a common phenomenon in severe primary hypothyroidism, we performed the LH-RH test on 4 additional patients with pituitary enlargement due to primary hypothyroidism. Two patients demonstrated aberrant ACTH secretion in response to LH-RH loading, but the others did not. To our knowledge, this is the first report of aberrant LH-RH-stimulated ACTH secretion in primary hypothyroidism.

Adrenocorticotropic Hormone↗

PubMed1999

Comparative study of assays for prostate-specific antigen molecular forms.

BACKGROUND: The detection of prostate-specific antigen (PSA) molecular forms such as free PSA and PSA-ACT and the use of PSA molecular ratios, especially the percentage of free to total PSA, have been reported to improve the diagnostic accuracy of prostate cancer in the patients with slightly elevated serum PSA values. However, the correlation among the values of serum free PSA or PSA-ACT obtained in various assays remains unclear. METHODS: Serum free PSA and PSA-ACT values were detected with the following assays: Hybritech, DPC, EIKEN, Abbott, Roche and Can-Ag for free PSA and Dainippon, Chugai, EIKEN and Bayer for PSA-ACT. The data obtained with each assay were compared with Hybritech (free PSA) and Dainippon (PSA-ACT) as standards. RESULTS: The free PSA data obtained with the Hybritech, EIKEN, Abbott and Can-Ag kits were similar. The values obtained with the DPC and Roche kits showed a linear regression of y = ax + b with those obtained with the Hybritech, with a b value of zero and an a value of 1.20 and 1.57, respectively. The serum PSA-ACT values detected with the Dainippon and Chugai kits were identical. The equation for converting the data obtained with the EIKEN kits to the Dainippon value was 0.7636 x (EIKEN) + 0.1381. CONCLUSIONS: Serum free PSA and PSA-ACT values obtained with various assays were not necessarily the same. Some kits for the assay of free PSA and PSA-ACT gave the same serum values. The free PSA values obtained with the other kits could be converted using appropriate equations. The gamma-Sm values showed wide variations and were not considered suitable as a measurement of free PSA.

Humans↗

PubMed1999

Prevention of cerebral vasospasm by a novel endothelin receptor antagonist, TA-0201.

This study was designed to examine the preventive effect of a novel endothelin (ET)-receptor antagonist TA-0201 on the cerebral vasospasm in a canine double-hemorrhage model. TA-0201 (10(-9)-10(-7) M) inhibited ET-1-induced vasoconstriction in the isolated canine basilar artery without endothelium in a concentration-dependent manner. Its pA2 value was 9.2 (ET(A) antagonism). In a canine double-hemorrhage model, intravenous treatment with TA-0201 (3 mg/kg, twice a day for 7 days) ameliorated the basilar artery narrowing significantly on day 7 compared with that in nontreated dogs. The reductions of the basilar artery diameter were 26.1+/-3.9% and 40.5+/-4.1% with and without TA-0201 treatment, respectively (p<0.05). Histologic study on day 7 indicated that treatment with TA-0201 inhibited vessel-wall damage such as disintegration of endothelium architecture and degeneration of medial smooth-muscle cells. We conclude that intravenous treatment with TA-0201 prevents the development of cerebral vasospasm and accompanying pathologic changes of the vessel wall, probably through blockade of ET(A) receptors.

Animals↗

PubMed1999

Effects of alpha-chlorohydrin on rat sperm motions in relation to male reproductive functions.

alpha-chlorohydrin (ACH) is a known male reproductive toxicant and produces antifertility in rats. The present experiments were performed to determine the relationship between sperm motions and reproductive function, and to further examine the possible mechanism for antifertility. ACH was administered to male rats for 9 days at 1, 3 and 10 mg/kg/day. The males were mated with untreated females and their reproductive status was determined. All mated males failed to impregnate females at 10 mg/kg/day. Low pregnancy rate associated with a decreased implant number was seen at 3 mg/kg/day. When sperm motions were analyzed using the CellSoft computer-assisted sperm analyzer, percentage of motile sperm, curvilinear velocity (VCL) and amplitude of lateral head displacement (ALH) were reduced at 10 mg/kg/day. At 3 mg/kg/day, VCL and ALH were reduced but the percentage of motile sperm was comparable to that of controls. In order to examine a possible mechanism for the effect of ACH on fertility, the number of sperm reaching the oviducts of mated females and the number of fertilized eggs was evaluated. Half of the females mated with ACH-treated males at 3 mg/kg/day had very low sperm numbers in the oviducts. At 10 mg/kg/day, all the mated females had a very low sperm number. The percent of fertilized eggs in the oviducts of mated females was decreased in a dose-dependent manner. These findings suggest that the effect of ACH on fertility was directly related to decreased VCL and ALH as well as percentage of motile sperm, and by the mechanism in which the sperm number reaching the oviducts after mating was reduced, so the reduction resulted in only a rare chance to fertilize.

Animals↗

PubMed1999

Prostate specific antigen density for discriminating prostate cancer from benign prostatic hyperplasia in the gray zone of prostate-specific antigen.

Serum prostate specific antigen (PSA) is currently the best blood marker for prostate cancer. However, low specificity for detection of prostate cancer, especially in the gray zone of PSA, is a problem. We evaluated the clinical significance of PSA density (PSAD) in gray zone PSA cases with conversion of serum PSA to a Stanford reference value. In a series of histologically confirmed 63 benign prostatic hyperplasia (BPH) patients and 234 prostate cancer patients, 36 BPH patients and 25 prostate cancer patients had gray zone PSA levels. Serum PSA was measured with the Markit-F or Markit-M PA assay. All data were converted to Stanford reference values. We used transabdominal ultrasound to determine prostate volume. PSAD was determined as the serum PSA/prostate volume ratio. The mean PSA values for BPH and prostate cancer were 6.42 +/- 1.80 and 7.80 +/- 2.15 ng/ml (p = 0.0116), respectively, and prostate volume was 33.4 +/- 14.1 ml and 17.1 +/- 8.2 ml, respectively (p < 0.0001). The mean PSAD for prostate cancer was 0.572 +/- 0.363 while that for BPH was 0.218 +/- 0.085 (p = 0.0001). Cut-off values with sensitivity > 90% were 0.218 for PSAD and 30 ml for prostate volume. At these cut-off values, specificity reached 56% for each marker. In discriminating prostate cancer from BPH in the gray zone of PSA, PSAD demonstrated better performance than PSA.

Aged↗