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Biomedical subjects

H Kaneko

Publications and source records attributed to H Kaneko.

At least 55 records · Page 3Linked to original sources
PubMed2001

Restoring ovulation in beef donor cows with ovarian cysts by progesterone-releasing intravaginal silastic devices.

The objective of this study was to determine the efficacy of a progesterone-releasing intravaginal silastic device (Controlled Internal Drug Release: CIDR) for inducing ovulation in beef cows with persistent ovarian cysts. Fifteen cows with cysts and abnormal cycles for over 40 days were randomly assigned to receive either a single CIDR (CIDR group, n=9), or a CIDR containing no progesterone (blank CIDR) (BLANK group, n=6) for about 14 days. Determination of plasma progesterone levels at the beginning of CIDR treatment indicated 4 of 6 BLANK cows with non-luteinized cysts and 5 of 9 CIDR cows with non-luteinized cysts. In 5 of 6 BLANK cows, one follicular wave appeared and newly emerged dominant follicles increased in size up to 20 mm in diameter and persisted during the experiment, while one cow experienced estrus with spontaneous ovulation. In contrast, during CIDR treatment, 2 or 3 waves, in which dominant follicles were from 7 to 15 mm in diameter, appeared approximately at 7-day intervals. Within 3 days after CIDR removal, estrous behavior was detected followed by ovulation of the dominant follicle in the last wave. All CIDR cows resumed normal cyclicity with 2 follicular waves for over 2 months. Insertion of a CIDR caused a rapid increase of about 2 ng/mL in plasma progesterone. The levels were greater than 1.3 ng/mL until removal of a CIDR, then dropped under 0.3 ng/mL. Concentrations of plasma estradiol in BLANK cows increased during growth of the cystic follicles, with high levels greater than 10 pg/mL for over 10 days. In 4 of 5 cows with non-luteinized cysts, with high plasma estradiol on the day of CIDR insertion, CIDR treatment resulted in rapid decline of estradiol levels. During placement of the CIDR, estradiol levels showed no increase in the growth phase of a newly appeared dominant follicle. After CIDR removal, however, estradiol significantly increased associated with the growth of ovulatory follicles in all 9 cows. A transient increase in plasma FSH levels preceded detection of each follicular or cyst wave in both BLANK and CIDR cows. Pulse frequency and mean concentration of LH in cows with non-luteinized cysts showed values corresponding to those in normal follicular phase. However, throughout CIDR treatment, these parameters reduced to levels found in the normal luteal phase. In cows with luteinized cysts, parameters of LH secretion were as low as in the normal luteal phase before and during CIDR treatment, then increased significantly after CIDR removal. Present results indicate that treatment with CIDR proved effective in restoring ovulation and reestablishing normal cyclicity in beef donor cows with cysts persistent for a long period. The CIDR reduced and maintained LH secretion at normal luteal levels, thereby, inducing atresia of estrogen-active cysts and preventing formation of cysts from the newly emerged follicles.

Administration, Intravaginal↗
PubMed2001

Effect of long-term potentiation induction on gamma-band electroencephalograms in prefrontal cortex following stimulation of rat hippocampus in vivo.

We examined whether long-term potentiation (LTP) affects cortical gamma-band electroencephalograms (EEG) in the hippocampo-prefrontal cortex (PFC) pathway of anesthetized rats. The LTP induction increased the evoked PFC gamma-band EEG power (40-100 Hz) to 120-135% at 500-700 ms after test stimulation. A simple increment of stimulus intensity, instead of LTP induction, did not reveal this evoked increase. Neither LTP induction nor the intensity increment changed significantly the magnitude of an evoked decrease at around 100 ms or the spontaneous prestimulation gamma-band power. These results indicate that LTP in PFC specifically increases the evoked gamma-band EEG power, which may reflect a phasic mode of plastic neurotransmission through the hippocampo-PFC pathway in vivo.

Animals↗
PubMed2001

Initial induction and subsequent reduction of alpha(2u)-globulin in urine and serum of mature male rats after repeated intraperitoneal injections of (anti)estrogen.

The influence of sex (anti)hormones on expression of alpha(2u)-globulin (a2uG) is complex and has not been sufficiently detailed. In order to assess the specificity of sex (anti)hormone action on a2uG expression and the utility of this approach as a sensitive screening method, mature male rats were given daily intraperitoneal injections of 17beta-estradiol (E2), dihydrotestosterone (DHT), tamoxifen (TX) and flutamide (FL) for 5 consecutive days. They were employed as representatives of estrogen, androgen, antiestrogen and antiandrogen categories, respectively. Urinary a2uG was specifically altered with E2 (1 microg/kg/day) and TX (50 mg/kg/day), but not by DHT (1 mg/kg/day) or FL (50 mg/kg/day). E2 and TX temporarily increased urinary a2uG on days 1 or 2, and days 2-4, respectively, followed by a return to the control level, and then a decrease with E2. The reduction in urinary a2uG on day 6 was more pronounced than the drop in serum a2uG. Serum hormone levels, and liver and testis weights were not remarkably altered with any treatment. Another strong xenoestrogen, diethylstilbestrol, also significantly reduced urinary and serum a2uG at 1 mg/kg/day on day 6. However, the other xenoestrogens (100 mg/kg/day of bisphenol A, nonylphenol, and dichlorodiphenyltrichloroethane, and 10 mg/kg/day of dieldrin) and phytoestrogens (10 mg/kg/day of genistein and daidzein) were without any appreciable influence. The results indicate that urinary a2uG is a sensitive indicator of estrogen action in mature male rats, with two different responses, initial induction and subsequent reduction.

Alpha-Globulins↗
PubMed2001

Living-related liver transplantation for type II citrullinemia using a graft from heterozygote donor.

BACKGROUND: Type II citrullinemia (CTLN2) characterized by a liver-specific argininosuccinate synthetase deficiency is an adult onset genetical disorder caused by the mutation of SLC25A13 gene, which results in fulminant hyperammonemia often with poor prognosis. METHODS: A 16-year-old Japanese boy presented fulminant hyperammonemia and encephalopathy and recovered after aggressive medical treatment. The patient was diagnosed as CTLN2 by plasma amino acid pattern and detection of the mutated SLC25A13 gene. We performed living-related liver transplantation (LRLT) using a graft from the genetically proven heterozygote father. RESULTS: Serum amino acid concentration was normalized within a day after transplantation without protein restriction and medication. The patient's postoperative course was natural. The patient is back in school 6 months after surgery. CONCLUSIONS: Living-related liver transplantation using a graft from genetically proven heterozygote donors might be a permissible treatment modality for CTLN2. Long-term observation may be necessary to make a definite conclusion possible.

Adolescent↗
PubMed2001

An in vitro reporter gene assay method incorporating metabolic activation with human and rat S9 or liver microsomes.

A metabolic activation system with an S9 fraction or liver microsomes was applied to a reporter gene assay in vitro for the screening of estrogenicity of chemicals. The endpoint (luciferase) was luciferase induction in cells transfected with a reporter plasmid containing an estrogen-responsive element linked to the luciferase gene. Compounds were applied to the reporter gene assay system after pretreatment or simultaneous treatment with an S9 fraction or liver microsomes. Both trans-stilbene and methoxychlor themselves showed no or little estrogenicity, but when they were treated with an S9 fraction or liver microsomes, they demonstrated strong effects, indicating their metabolites to be estrogenic. When four pyrethroid insecticides were subjected to this assay system, however, they showed no estrogenicity even with liver microsome or S9 mix treatment.

Animals↗
PubMed2001

Evaluation of in vitro methods for detecting the effects of various chemicals on the human progesterone receptor, with a focus on pyrethroid insecticides.

The progesterone receptor (PR) is associated with physiological events such as implantation and the maintenance of pregnancy. Recently, it has become a social concern that chemicals may exert agonistic or antagonistic effects on hormone receptors. Therefore, we examined the effects of various chemicals on the human PR, with a focus on pyrethroid insecticides, using three in vitro methods. Eight pyrethroid insecticides (fenvalerate, d-allethrin, d-phenothrin, prallethrin, empenthrin, permethrin, cypermethrin and imiprothrin), examples of environmental pollutants and positive control chemicals were subjected to a reporter gene assay (luciferase assay) using human breast cancer T-47D cells, a two-hybrid assay and a binding assay using the same whole cells or receptors (cell-free). In none of these did the eight pyrethroid insecticides show any binding to the PR, agonistic or antagonistic effects.

Binding, Competitive↗
PubMed2001

A novel single-nucleotide polymorphism at the 5'-flanking region of SAA1 associated with risk of type AA amyloidosis secondary to rheumatoid arthritis.

OBJECTIVE: To address whether the gamma haplotype at exon 3 of the SAA1 gene is directly associated with type AA amyloidosis or is merely in linkage with an unknown polymorphism that is primarily associated with disease risk, we examined the SAA1 gene for new polymorphisms. METHODS: We analyzed DNA samples from 44 rheumatoid arthritis (RA) patients with AA amyloidosis (amyloid group), 55 RA patients without AA amyloidosis (RA group), and 58 non-RA healthy subjects (non-RA group). We also examined DNA samples from 50 Caucasians to compare linkage disequilibrium relationships involving SAA1 region polymorphisms between Japanese and Caucasoid populations. RESULTS: We observed 3 novel single-nucleotide polymorphisms (SNPs) in the 5'-flanking region of SAA1: -61C/G, -13T/C, and -2G/A. Comparison of allele frequencies and ratios of individuals with particular alleles between the study groups revealed statistically significant differences between the amyloid and RA groups and between the amyloid and non-RA groups. Statistical analysis revealed that the -13T/C SNP was strongly associated with AA amyloidosis. In addition, we found tight linkage between the -13T allele and the alpha haplotype, rather than the beta haplotype, at exon 3 in the Caucasoid population, while -13T was closely linked to the gamma and beta haplotypes, rather than the alpha haplotype, in the Japanese population. Since the linkage disequilibrium relationship was reversed between the Japanese and Caucasoid populations, different exon 3 haplotypes of SAA1 are found to be associated with the risk of AA amyloidosis in different ethnic groups. CONCLUSION: Our data suggest that the SAA1 -13T allele, rather than SAA1 exon 3 haplotypes, is primarily associated with AA amyloidosis risk.

Amyloidosis↗
PubMed2001

Reassessment of monoethylglycinexylidide as preoperative liver function test in a rat model of liver cirrhosis and man.

It is known that lidocaine is rapidly metabolized by the hepatic cytochrome P-450 system to form monoethylglycinexylidide (MEGX), its primary metabolite. We analyzed serum MEGX levels experimentally and clinically by fluorescent polarization immunoassay to reassess preoperative liver microsome functions. EXPERIMENTAL STUDY: Liver cirrhosis was produced in rats by intra-abdominal injection of thioacetamide. MEGX, indocyanine green test (ICG), and liver biochemical variables were measured periodically. Then, survival rates were assessed after the rats received a 70% hepatectomy. CLINICAL STUDY: MEGX levels were measured in various human patients with chronic hepatitis or liver cirrhosis who underwent hepatectomy. Serum MEGX levels significantly dropped and ICG levels significantly rose with macroscopic and histologic progression of liver cirrhosis in rats. The MEGX levels correlated closely with albumin levels and ICG. Preoperative MEGX and ICG levels of the mortal group of rats differed significantly from those of the survival group with 70% hepatectomy. Furthermore, 100% of the rats with MEGX levels above 40 ng/ml and ICG levels below 1.0%. In the clinical study, MEGX levels were significantly lower in patients with chronic hepatitis or liver cirrhosis than in healthy volunteers and correlated significantly with liver function tests such as albumin, Fischer's ratio, prothrombin time, hepaplastin and ICG. A significant difference was found in MEGX levels between patients receiving lobectomy and those receiving subsegmentectomy or partial hepatectomy. All patients tolerated their operations. Our data indicate that the MEGX test combined with ICG test and Child-Pugh classification is a better predictor of residual liver reserve capacity, and the analysis of hepatic MEGX formation might prove useful for rapid and reliable assessment liver function and choice of surgical treatment.

Alanine Transaminase↗
PubMed2001

Antiviral activity of NMSO3 against adenovirus in vitro.

NMSO3, a sulfated sialyl lipid, was evaluated for its efficacy against adenovirus (AdV) in vitro. The median effective concentration (50% effective concentration, EC(50)) of NMSO3 against replication of AdV type 2 (AdV2), type 4 (AdV4), type 8 (AdV8) and type 37 (AdV37) was 0.21-0.71 microg/ml in HEp-2 cells and 1.01-1.41 microg/ml in MKN-28 cells. The EC(50) values of NMSO3 were lower than those of HPMPC and ddC, which were also evaluated. NMSO3 exhibited minimal cytotoxicity against HEp-2 cells and MKN-28 cells, both for which the median cytotoxic concentration (50% cytotoxic concentration, CC(50)) was more than 1000 microg/ml. NMSO3 was the most potent and selective anti-AdV compound of those examined. NMSO3 inhibited AdV infection of HEp-2 cells only when present during the virus adsorption period. A virus binding assay using radiolabeled AdV4 revealed that NMSO3 inhibited viral binding to the HEp-2 cells. NMSO3 itself bound to the virus particles, but not to the HEp-2 cell membrane. Thus, the mechanism of anti-AdV activity by NMSO3 involves inhibition of virus adsorption to cells by NMSO3 binding to viral particles.

Adenoviridae↗
PubMed2001

Effect of vincristine on gastric motility in conscious rats.

We investigated the possible involvement of the upper alimentary tract in vincristine (VCR)-induced dysmotility. Gastric contractions were recorded by a strain-gauge force transducer in conscious rats. Rats were injected with various doses of VCR followed by continuous recording for 12 hr. Additionally, 3-hr recordings to study the later effects were performed one and three days after injection. Gastric motility was dose-dependently increased by VCR. Post- versus preinjection motility index (MI; area under contraction waves) ratios were 0.78+/-0.12 for saline and 1.95+/-0.21 for VCR at 0.75 mg/kg. This increase in MI was completely inhibited by atropine and hexamethonium. MI one day after injection of VCR (0.75 mg/kg) was significantly less than in control (0.32+/-0.10 vs 0.92+/-0.24, respectively). The decrease was reversed by acetylcholine. In conclusion, VCR first increased gastric motility, and this was followed by a gradual decrease in conscious rats. These alterations may involve a presynaptic cholinergic pathway.

Acetylcholine↗
PubMed2001

The role of ultrasonography in the detection of adrenal masses: comparison with computed tomography and magnetic resonance imaging.

To compare detection rates of adrenal tumors by ultrasonography, computed tomography and magnetic resonance image, we studied 61 patients with adrenal tumor, who underwent adrenalectomy. In 45 (73.8%) of the 61 patients. adrenal tumor was detected by ultrasonography. However, computed tomography and magnetic resonance imaging could detect all adrenal tumors. All adrenal tumors measuring more than 3.0 cm in diameter were detected by ultrasonography, computed tomography and magnetic resonance image. When adrenal tumors were smaller than 3.0 cm. however, ultrasonography, computed tomography and magnetic resonance imaging correctly found adrenal tumors in 30 (65.2%) and 46 (100.0%) of 46 patients and 30 (100.0%) of 30 patients, respectively. These facts suggest that ultrasonography seems to be an effective diagnostic procedure for the prevention of overlooking adrenal tumors larger than 3.0 cm.

Adolescent↗
PubMed2001

International prognostic scoring system and TP53 mutations are independent prognostic indicators for patients with myelodysplastic syndrome.

We applied the International Prognostic Scoring System (IPSS) to our series of 118 patients with myelodysplastic syndrome (MDS) to determine its validity, and also used univariate and multivariate analyses to evaluate the prognostic significance of TP53 configurations. Sixteen patients with the mutation had a strikingly worse prognosis and the multivariate analysis demonstrated that this alteration was the most significant factor. The prognostic comparison between patients with and without the mutation within each IPSS subgroup showed a significant difference in the intermediate subgroups. A combination of clinical manifestations and genetic configurations provided us with more accurate prognostic information in MDS patients.

Adolescent↗
PubMed2001

Identification of beta-lactoglobulin-derived peptides and class II HLA molecules recognized by T cells from patients with milk allergy.

BACKGROUND: Cow's milk allergy impairs the health and development of many infants since it deprives them of adequate nutrition. Cow's milk fractions contain many allergens, and beta-lactoglobulin (BLG) is one of the major allergens. OBJECTIVE: The purpose of this study was to determine T cell epitopes, antigen-presenting molecules and cytokine production by T cells in relation to BLG. The results can provide new therapeutic possibilities of using analogue peptides of BLG for infants with cow's milk allergy. METHODS: Using a mixture of a panel of overlapping synthetic peptides that cover the entire BLG molecule, we established polyclonal BLG-specific short-term T cell lines and clones from peripheral blood mononuclear cells of four patients with allergy to cow's milk carrying most of the common human leucocyte antigen (HLA) haplotypes seen in the Japanese population. We then identified the T cell epitopes and antigen-presenting molecules, and measured the production of cytokines interleukin (IL)-4, IL-5 and interferon-gamma in the culture supernatants. RESULTS: The T cell lines established from the four patients responded to seven different peptides. Three of the peptides stimulated the T cells of two donors, regardless of the HLA types. The patterns of inhibition of the proliferative responses of the cell lines by anti-HLA class II antibodies were heterogeneous; three were mainly inhibited by anti-HLA-DR mAbs, and the other was inhibited by anti-HLA-DQ mAbs. High levels of IL-5 were produced by these T cell lines. CONCLUSIONS: Patients' T cells recognized BLG in association with a variety of HLA-DR or -DQ as antigen-presenting molecules. Although some peptides did have a more potent T cell stimulatory activity than others, the T cell receptor ligands formed with the BLG molecule are heterogeneous. Peptides for the desensitization of T cells of the patients with cow's milk allergy need to be designed keeping in mind the different requirements in different ethnic groups.

Amino Acid Sequence↗
PubMed2001

IFN-gamma production in response to IL-18 or IL-12 stimulation by peripheral blood mononuclear cells of atopic patients.

BACKGROUND: Several studies have shown that interleukin (IL)-4 and interferon-gamma (IFN-gamma) are important for the regulation of immunoglobulin E (IgE) production and that IL-18 and IL-12 induce IFN-gamma. OBJECTIVE: IFN-gamma production in response to IL-18 or IL-12 stimulation was investigated in peripheral blood mononuclear cells (PBMCs) of atopic patients with various levels of serum IgE. METHODS: Cytokine production from PBMCs was measured following stimulation with a non-specific stimulator (phytohemagglutinin: PHA), IL-18 or IL-12 in 12 healthy controls and 26 atopic patients with various serum IgE levels. RESULTS: IFN-gamma production by IL-18-stimulated PBMCs was positively correlated with IFN-gamma production by IL-12-stimulated PBMCs (P < 0.05). However some atopic patients showed discrepancy between the levels of IFN-gamma production stimulated by IL-12 and by IL-18. CONCLUSIONS: The results shown here suggest the presence of abnormalities in the IL-12 and/or IL-18 signalling pathways, such as genetic defects in the atopic patients.

Adolescent↗
PubMed2001

School refusal and depression with school inattendance in children and adolescents: comparative assessment between the Children's Depression Inventory and somatic complaints.

School refusal has become a relatively common problem of increasing magnitude in Japan. Although clarification of the relationship between 'school refusal' and 'depression with school inattendance' is crucial in light of the difference in treatment modalities involved, it is not clear whether the two are to be regarded along the same tangent or as disparate entities. For clarification, a comparison was made between clinical diagnosis, Children's Depression Inventory (CDI) scores, and scores for the three subordinate scales of the CDI in 34 cases of school refusal, 10 cases of depression with school inattendance, and normal students. Significant difference in CDI score was noted between the three groups: highest among depression cases, followed by school refusers, and lowest in normal students. A larger proportion of school refusers expressed somatic complaints together with low CDI scores. The typical case of school refusal appears to exhibit somatic complaints in the foreground rather than depression, both clinical characteristics and CDI scores indicate school refusal and depression to be separate entities. Although many approaches are being taken in the treatment of school refusal, the results appear to justify primacy of the psychotherapeutic approach with the possible adjuvant use of pharmacological agents, for the phenomenon as it presents in Japan.

Adolescent↗
PubMed2001

Interactions among gastric somatostatin, interleukin-8 and mucosal inflammation in Helicobacter pylori-positive peptic ulcer patients.

BACKGROUND: To investigate whether Helicobacter pylori infection, but not drugs, affects gastric somatostatin, interleukin-8 (IL-8), histological inflammation through eradication therapy, and interactions among these parameters. METHODS: Twenty-eight H. pylori-positive patients (21 males; mean age 47.0 years) with either gastric ulcer (GU: n = 11) or duodenal ulcer (n = 17) diagnosed endoscopically were treated with dual therapy. Eradication was defined as negative microbiologic tests and 13C-urea breath test. Levels of antral and gastric juice somatostatin and mucosal IL-8 were measured by radioimmunoassay and enzyme-linked immunosorbent assay, respectively. Histology was assessed by the Sydney system. RESULTS: H. pylori was eradicated in 15 patients (10 males, 6 GU) out of 28 (54%). The patients' backgrounds did not affect the eradication of H. pylori. Successes in eradication significantly increased antral and juice somatostatin contents, and dramatically decreased IL-8 levels and histological gastritis. In contrast, persistent H. pylori infection did not affect somatostatin and histological gastritis. An inverse correlation was present between changes in somatostatin levels and histological activity. No relationship was observed in changed values between antral somatostatin and IL-8. CONCLUSIONS: These results indicate that eradication of H. pylori, but not the drugs used, induced an increase in somatostatin levels in the antrum and gastric juice, suggesting a close relationship between H. pylori and gastric somatostatin regulation. A close correlation between an increase in gastric somatostatin levels and the normalization of histological activity was present, suggesting that certain peptide-immune interactions in the gastric mucosa exist in H. pylori infection.

Adult↗