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Biomedical subjects

T Tsukamoto

Publications and source records attributed to T Tsukamoto.

At least 145 records · Page 8Linked to original sources
PubMed1999

Apolipoprotein E epsilon 4 allele and Japanese late-onset depressive disorders.

BACKGROUND: Several studies have suggested that late-onset depressive disorder (LOD) and the apolipoprotein E (Apo E) epsilon 4 allele are associated with dementia, respectively. The Apo E polymorphism is significantly heterogeneous among races. We hypothesized that the Apo E epsilon 4 allele frequency is elevated in Japanese LOD. METHODS: The Apo E genotype was studied in 134 patients (male, 53; female, 81) with early-/late-onset depressive disorder and 105 healthy normal controls (male, 41; female, 64). The patients were subdivided into those with early onset and late onset using 45 and 50 years as the cutoff ages. All the subjects were Japanese. RESULTS: There was statistically no difference between normal control subjects and patients with depressive disorders in Apo E genotype or allele frequency. There was statistically no difference in the age of onset of depressive disorders according to the Apo E genotype. There was no relation between the age of onset of depressive disorder and the number of epsilon 4 alleles the patient had. There was also no association between early-/late-onset depressive disorder and the Apo E genotype or allele frequency. CONCLUSIONS: Our results suggest that there is no association between the Apo E epsilon 4 allele and Japanese LOD.

Adult↗
PubMed1999

Separation of enantiomers on a chiral stationary phase based on ovoglycoprotein. III. Effect of aggregation of ovoglycoprotein on chiral resolution.

Ovoglycoprotein from chicken egg whites (OGCHI) subjected to 80 degrees C has produced the associated OGCHI, which is a heat-induced aggregate of OGCHI. The molecular weight of the aggregate was estimated to be ca. 5.7 million daltons by a low-angle laser light-scattering detection. The heat-induced aggregate of OGCHI was found to dissociate reversibly to the OGCHI monomer. The OGCHI aggregate has little chiral recognition ability, or has much lower chiral recognition ability than the native OGCHI. Further, the OGCHI monomer from the reversibly dissociated OGCHI aggregate has chiral recognition ability comparable to that of the native OGCHI.

Chromatography, Gel↗
PubMed1999

Genomic structure and identification of 11 novel mutations of the PEX6 (peroxisome assembly factor-2) gene in patients with peroxisome biogenesis disorders.

The PEX6 (peroxisome assembly factor-2, PAF-2) gene encodes a member of the AAA protein (ATPases associated with diverse cellular activities) family and restores peroxisome assembly in fibroblasts from peroxisome biogenesis disorder patients belonging to complementation group C (group 4 in the United States). We have now clarified the genomic DNA structure of human PEX6 and identified mutations in patients from various ethnic groups. The human PEX6 gene consists of 17 exons and 16 introns, spanning about 14kb. The largest exon, exon 1, has at least 952 bp nucleotides. Eleven novel mutations (18 alleles) were identified by direct sequencing of the PEX6 cDNA from 10 patients. All these mutations have been confirmed in the corresponding genomic DNA. There was no common mutation, but an exon skip was identified in two unrelated Japanese patients. Most of the mutations led to premature termination or large deletions of the PEX6 protein and resulted in the most severe peroxisome biogenesis disorder phenotype of Zellweger syndrome. A patient with an atypical Zellweger syndrome had a missense mutation that was shown to disrupt the cell's ability to form peroxisomes. This mutation analysis will aid in understanding the functions of the PEX6 protein in peroxisomal biogenesis. Hum Mutat 13:487-496, 1999.

ATPases Associated with Diverse Cellular Activitie↗
PubMed1999

Isolation of oncogenes from rat mammary tumors by a highly efficient retrovirus expression cloning system.

A majority of mammary tumors induced with N-methyl-N-nitrosourea in rats contain G to A transitional mutation of c-Ha-ras at the 12th codon. Additional oncogene activation is known to be necessary for further tumor progression. To isolate novel oncogenes, we used an expression cloning system utilizing the pMX retroviral vector in combination with BOSC23 packaging cells. First, we elucidated the sensitivity of this system in the NIH 3T3 focus assay; foci were detectable even after 10(-6) dilution using v-Ha-ras, neuT, and beta-galactosidase constructs in pMX vector. This system is sensitive enough to detect low copy number cDNAs. We used the pMX/BOSC23 expression cloning system to clone novel oncogenes from rat mammary tumors harboring an activated c-Ha-ras and isolated several candidate oncogenes that caused transformation of NIH 3T3 cells and/or generated tumors when transplanted to nude mice.

3T3 Cells↗
PubMed1999

Analysis of the genes responsible for the O-antigen synthesis in enterohaemorrhagic Escherichia coli O157.

The genes responsible for O157 O-antigen synthesis were cloned from Shiga toxin 1 (Stx1)-producing enterohaemorrhagic Escherichia coli O157:H-. Based on the published sequence of the rfbE(EcoO157:H7) gene, the rfbE gene was amplified by PCR and used as the probe. One clone (1-4-1) out of ten agglutinated using the slide agglutination test with O157 antiserum. The DNA sequence of a 31.5 kb fragment in p1-4-1 was determined and found to contain 26 open reading frames (ORFs). These ORFs were organized as two clusters of genes, comprising orf2 to orf16 and orf17 to orf24 regions, which were aligned in opposite directions. The GC contents of orf1, orf12 and orf14 to orf26 were similar to the overall GC content of the E. coli chromosome (51%). However, orf2 to orf11 and orf13 showed a much lower GC content of 30.0 to 39.4%. The minimum region essential for O157 O-antigen expression in E. coli K-12 lay between orf2 and orf13, which corresponded to the region of low GC content in E. coli O157. A colony hybridization test was carried out against reference strains of E. coli representing serogroups O1 to O173 using O157 O-antigen synthesis genes (orf2-orf13) of E. coli O157 as probes. With the exception of orf12, all probes from E. coli O157 O-antigen synthesis gene cluster did not hybridize with DNA from E. coli O1 to O173, except O157 reference strains, under high stringency conditions. These data suggest that the region from orf2 to orf13 has originated from a non-E. coli species with a low GC content.

Bacterial Proteins↗
PubMed1999

Induction of apoptosis in metastatic foci from human gastric cancer xenografts in nude mice and reduction of circulating tumor cells in blood by 5-FU and 1-hexylcarbamoyl-5-fluorouracil.

Antimetastatic effects of 5-FU and its derivative, 1-hexylcarbamoyl-5-fluorouracil (HCFU) on human gastric cancer micrometastasis and their mode of action were evaluated, using a spontaneous lung metastasis model (HY-1) in nude mice. Metastases were first detected in the lung from 4 weeks after subcutaneous transplantation, growing intravascularly and forming micrometastases at 100% incidence by 6 weeks after implantation. Lung metastasis in mice bearing subcutaneous tumors was significantly inhibited by HCFU at doses of 100-150 mg kg(-1) day(-1) without severe toxic side-effects, when orally administered three times per week either from week 4 or week 6 to 9 weeks after implantation. Spontaneous lung metastasis was also inhibited by the administration of 5-FU, but to lesser extent than with HCFU at equimolar low doses. Apoptosis within primary tumors and lung metastatic foci, as detected by the terminal-deoxynucleotidyltransferase-mediated dUTP nick-end labeling method, was found to be significantly enhanced by HCFU as well as 5-FU administration at doses of more than 100 mg kg(-1) day(-1) and 50 mg kg(-1) day(-1) respectively. However, proliferating activity of the metastatic foci, as evaluated by MIB-1 immunostaining, was not significantly suppressed by HCFU or 5-FU treatment. Furthermore, polymerase chain reaction analysis using human specific primers for the beta-globin gene, which proved to be capable of detecting 10 tumor cells/ml mouse blood, revealed that circulating tumor cells in the peripheral blood of mice bearing primary tumors were reduced by HCFU or 5-FU administration. These results indicate that circulating tumor cells in blood and micrometastases in the lung are sensitive to these chemotherapeutic agents, and suggest that the anti-metastatic effect of these agents is mediated, at least in part, by enhanced apoptosis rather than by inhibition of cell proliferation.

Animals↗
PubMed1999

Influence of histological inflammatory activity on regenerative capacity of liver after percutaneous transhepatic portal vein embolization.

Percutaneous transhepatic portal vein embolization (PTPE) produces regenerative hypertrophy in the nonembolized part of the liver, but the regenerative capacity after PTPE in patients with chronic hepatitis is unknown. We studied 34 patients with hepatocellular carcinoma and chronic hepatitis who underwent PTPE at the right portal vein. Hepatic lobular volumes were calculated by computed tomography before and 2 weeks after PTPE. The increase in left lobular volume was analyzed using a stepwise multiple regression method incorporating 11 factors: age; portal venous pressure; proportional volume of the right lobe; indocyanine green retention test; platelet count; serum levels of aspartate transaminase, alanine transaminase, total bilirubin, and albumin; and histological inflammatory grade and stage of fibrosis, according to the criteria of the International Association for the Study of the Liver recommended at their 1994 meeting. The median volume of the left lobe had increased from 405 to 554 cm3 (P < 0.0001) by 2 weeks after PTPE. Inflammatory grade was the only independent factor predicting regenerative hypertrophy (regeneration ratio (%) = 80.3 - 20.1 x grade; standard correlation coefficient = -0.566; P = 0.0014). Histological inflammatory activity was the essential factor regulating liver regeneration after PTPE in patients with chronic hepatitis.

Aged↗
PubMed1999

The effects of alterations in nitric oxide levels in the paraventricular nucleus on copulatory behavior and reflexive erections in male rats.

PURPOSE: To examine the effects of altered nitric oxide (NO) levels in the paraventricular nucleus (PVN) on copulatory behavior and reflexive erections in male rats. MATERIALS AND METHODS: Extracellular nitrite (NO2-) and nitrate (NO3-) levels were measured in the PVN following administration of the NO precursor L-arginine (L-arg, 10 mM), the NO synthase inhibitor N(G)-monomethyl L-arginine (L-NMMA, 10 mM), or Ringer's solution via a dialysis probe to the PVN. The effects of alterations in extracellular NO on reflexive erections and copulatory behavior were assessed. RESULTS: L-arg administration was associated with significant elevations of extracellular NO2- and NO3- in the PVN, while L-NMMA significantly reduced NO2- and NO3- levels. A corresponding increase in reflexive erections was noted during infusion of L-arg in the PVN, with a corresponding decrease in reflexive erections observed during administration of L-NMMA into the PVN (Student's t test for paired samples, p <0.05). Mount rate was unaffected by infusion of the either L-arg or L-NMMA. CONCLUSIONS: Altered NO levels in the PVN affected the frequency of reflexive erections, but not the mount rate. These studies contrast with previous observations of the effects of altered NO levels in the MPOA, and support the hypothesis that physiological specificity in the actions of NO on discrete brain nuclei may have important implications to erectile physiology and dysfunction.

Animals↗
PubMed1999

Decline of sexual function with age in Japanese men compared with American men--results of two community-based studies.

OBJECTIVES: To investigate the self-reported sexual function of Japanese men aged 40 to 79 years in a community-based study and compare the results to a similarly conducted study in Olmsted County, Minnesota. METHODS: Two hundred eighty-nine Japanese and 2115 American men from the community were queried about ability to have erections when stimulated, sexual drive, and satisfaction with sexual activity using a self-administered questionnaire. RESULTS: Both Japanese and American men showed an age-related decline in erectile function, sexual libido, and sexual satisfaction. In particular, 71% of Japanese men aged 70 to 79 years reported having erections only a little of the time or less when sexually stimulated, and 80% perceived sexual drive once per month or less during the past month. Although more Japanese than American men reported erectile dysfunction and decreased libido, there were no striking differences in self-reported sexual satisfaction between the studies. However, cultural and perceptual differences could play a role in these results, despite attempts to ensure linguistic equivalency in the questionnaires. CONCLUSIONS: Although erectile dysfunction and decreased libido were noted by a greater proportion of Japanese than American men, the self-reported degree of satisfaction was comparable between the studies. Perceptions of elderly male sexual function and its impact on health-related quality of life may differ among races, sites, and countries.

Adult↗
PubMed1999

A variable-number-tandem-repeat of the serotonin transporter gene and anxiety disorders.

1. A polymorphism of the variable-number-tandem-repeat (VNTR) in the second intron of the serotonin transporter (ST) gene, which has been reported to be associated with major depression, was studied in anxiety disorders. 2. The VNTR of the human ST gene was compared between 103 patients with anxiety and 106 controls. 3. The frequency of the allele containing 12 copies of the VNTR element (STin2.12) was significantly higher in the combined patient group (p = 0.027), and among patients with OCD (p = 0.0326), and GAD (p = 0.0123), in comparison with in controls. 4. The presence of the STin2.12 allele was significantly associated with the risk of combined anxiety disorders (odds ratio = 2.06, 95% CI 1.09-3.90), OCD (10.2, 1.34-77.4), and GAD (3.61, 1.23-10.6).

Adolescent↗
PubMed1999

Biofilm in complicated urinary tract infection.

We studied the clinical efficacy of oral treatment with ciprofloxacin (CPFX) alone and combined with clarithromycin (CAM) in patients with complicated urinary tract infection with or without an indwelling catheter. Patients were randomly allocated to 600 mg CPFX (CPFX group) or to 600 mg CPFX plus 600 mg CAM (combination group) for 14 days. Evaluation was done on day 14 according to the criteria advocated by the Japanese Urinary Tract Infection Committee. In patients with a urinary catheter, the combination achieved a higher complete bacterial elimination rate (50.0%) and clinical efficacy rate (83.9%) than CPFX alone (30.0 and 61.5%, respectively). While no significant difference was found in the bacterial elimination rate between the two groups, the clinical efficacy of the combination (40.0%) was superior to that of CPFX alone (23.3%) in patients with an indwelling catheter. The better clinical efficacy of the combination may partly be attributed to the antibiofilm effect of CAM in the clinical setting. The results also indicate that difficulties still remain in the treatment of complicated urinary tract infections in patients with an indwelling catheter.

Adult↗
PubMed1999

Angiomyofibroblastoma of the female urethra.

BACKGROUND: Angiomyofibroblastoma is a relatively recently described rare tumor of the superficial soft tissues. To date, 57 cases of angiomyofibroblastoma of the external genitalia in women have been reported. METHODS/RESULTS: We describe a case of a 24-year-old woman who presented with the urinary stream flowing out in the posterior direction and whose diagnosis was a urethral tumor, angiomyofibroblastoma. CONCLUSIONS: Angiomyofibroblastoma has a potential arising from the female urethra as well as other areas of the external genitalia.

Actins↗
PubMed1999

Quality of life in patients having an ileal conduit, continent reservoir or orthotopic neobladder after cystectomy for bladder carcinoma.

BACKGROUND: To compare the QOL in patients with ileal or colon conduits (IC), continent urinary reservoir (CR) and ileal neobladder (NB), a retrospective study was conducted using a questionnaire sent by mail. METHODS: Seventy-nine patients with a mean age of 60 years were included in this study. A total of 36, 22 and 21 underwent IC, CR and NB, respectively and were alive at the time of this study. A structured questionnaire consisting of 97 questions that covered general condition and physical condition, reconstruction-related symptoms, psychological status, sexual life, social status and satisfaction with the treatment was employed. RESULTS: The IC group frequently complained of changes in bathing habits and loss of using public baths in comparison with the CR and the NB groups. High scores for loss of sexual desire were obtained in the IC, the CR and the NB groups, in this order. Because of the nearly physiological voiding, the NB group desired a voiding condition like pre-operative status as compared with the IC and the CR groups. However, for most of the questionnaire items no difference was seen among the IC, CR and NB groups concerning general condition, reconstruction-related symptoms, psychological status, sexual life, social status, satisfaction with the treatment and global satisfaction with life and health. CONCLUSIONS: There was little difference in the QOL score of the questionnaire and satisfaction among the IC, CR and NB groups. It was suggested that almost every patient accepted and adapted to the present status of general quality of life in each group.

Adult↗
PubMed1999

Pelvic lipomatosis associated with proliferative cystitis: case report and review of the Japanese literature.

PURPOSE: We report only the second known patient with pelvic lipomatosis associated with proliferative cystitis in the Japanese literature, a 43-year-old mildly obese Japanese male who demonstrated radiographic findings characteristic of pelvic lipomatosis. METHODS: Cystourethrography revealed an elevated pear-shaped bladder and an elongated and anteriorly displaced prostatic urethra. Computed tomography demonstrated excess intrapelvic fat that exhibited a density identical to that of subcutaneous fat tissue. Cystoscopic and histologic examination revealed concomitant proliferative cystitis composed of von Brunn's nest, cystitis cystica and cystitis glandularis, but no malignant cells. RESULTS/CONCLUSIONS: As a result of dietary control for 15 months, the proliferative cystitis improved mildly, but the amount of fat was unchanged.

Adult↗
PubMed1999

Urinary nuclear matrix protein 22 as a new marker for the screening of urothelial cancer in patients with microscopic hematuria.

PURPOSE: The aim of the present study was to determine the clinical usefulness of nuclear matrix protein 22 (NMP22) as a new urinary marker for the screening of urothelial cancer in patients with microscopic hematuria, especially in comparison with that of voided urine cytology. METHODS: Patients with microscopic hematuria detected at a health examination, who were advised by a consulted urologist to have a cystoscopical examination, were asked to enter this study. Urine samples were collected before cystoscopy and divided into two portions for NMP22 test and voided urine cytology. RESULTS: Of the 309 patients with microscopic hematuria, 22 cases (7.1%) of urothelial cancer and one case of prostate cancer were detected. For the other cases, 128 (41.4%) were of benign diseases and 158 (51.1%) were designated as having no evidence of disease (NED). The median NMP22 values for urothelial cancer, other diseases and NED were 35.5, 6.7 and 6.0 U/mL, respectively, with 95% confidence intervals of 19.9-228.2, 5.1-9.3 and 5.4-7.2, respectively. The sensitivity of the NMP22 test for urothelial cancer was 90.9% (20/22), whereas the sensitivity of voided urine cytology was only 54.5% (12/22). CONCLUSIONS: The present study indicates that urinary NMP22 is a useful tool for the screening of urothelial cancer in patients with microscopic hematuria.

Adult↗
PubMed1999

Hematospermia: an investigation of the bleeding site and underlying lesions.

BACKGROUND: The site of hemorrhage and causative lesions in patients with hematospermia were evaluated using the puncture technique for seminal vesicles and/or müllerian duct cysts under ultrasound guidance. METHODS: Twenty-one patients aged 26-75 years (mean, 49.8 years) underwent transperineal needle aspiration of the seminal vesicles and/or müllerian duct cysts guided by transrectal ultrasonography (TRUS). RESULTS: Dark reddish seminal vesicle fluid was aspirated and the site of bleeding was considered to be the seminal vesicles in 11 patients (52%) (group A). In group A, abnormalities of the seminal vesicles were noted in nine patients (82%). These consisted of dilated seminal vesicles in seven (bilateral in four, unilateral in three), a seminal vesicle cyst in one and seminal vesicle amyloidosis in one. A müllerian duct cyst was confirmed to be the bleeding site in two patients (10%; group B). The bleeding site was estimated to be organs rather than the seminal vesicles in four patients (group C), in all of whom ectopic prostatic tissue was observed in the prostatic urethra. In groups B and C, seminal vesicle abnormalities were not detected by TRUS. In the remaining four patients (group D), failure to aspirate seminal vesicle fluid means that it is unclear whether hemorrhage was from the seminal vesicle or from another source. In group D, ectopic prostatic tissue was demonstrated in the prostatic urethra of three patients and unilateral seminal vesicle dilation was detected by TRUS in one patient. CONCLUSION: Puncture of the seminal vesicles and/or mullerian duct cysts under ultrasonic guidance as well as cystourethroscopy is a useful and minimally invasive examination for determination of the bleeding site responsible for hematospermia.

Adult↗
PubMed1999

Helicobacter pylori infection enhances glandular stomach carcinogenesis in Mongolian gerbils treated with chemical carcinogens.

Helicobacter pylori (Hp) is thought to be a stomach carcinogen from epidemiological findings. To determine the effects of infection with the bacteria on experimental carcinogenesis, a study of the glandular stomach of Mongolian gerbils (MGs) was performed. Male MGs were treated with N-methyl-N'-nitro-N-nitrosoguanidine followed by inoculation with Hp or infected with Hp followed by N-methyl-N'-nitro-N-nitrosoguanidine administration. Animals were killed at week 50, and their excised stomachs underwent microbiological and histopathological examinations. In addition, a serological investigation was performed. The incidences of adenocarcinomas were significantly higher in animals treated with 60 or 300 p.p.m. N-methyl-N'-nitro-N-nitrosoguanidine for 10 weeks followed by Hp inoculation or Hp followed by 20 p.p.m. N-methyl-N'-nitro-N-nitrosoguanidine for 30 weeks than in the respective controls. Moreover, tumour-bearing animals had higher titres of anti-Hp antibodies than tumour-free animals. Of interest was the finding that a dose of 100 p.p.m. N-methyl-N'-nitro-N-nitrosoguanidine given to infected gerbils eradicated the Hp in about half the animals, with a concomitant reduction in the promoting effect. No tumours were found in animals infected with Hp without N-methyl-N'-nitro-N-nitrosoguanidine or non-treated gerbils. Hp infection enhances glandular stomach carcinogenesis in MGs treated with N-methyl-N'-nitro-N-nitrosoguanidine. Animals with high titres of anti-Hp antibodies are at greatest risk of developing neoplasms.

Adenocarcinoma↗