Biomedical subjects

N Takeda

Publications and source records attributed to N Takeda.

At least 91 records · Page 5Linked to original sources

PubMed2000

A multivariate analysis of blood vessel and lymph vessel invasion as predictors of ovarian and lymph node metastases in patients with cervical carcinoma.

BACKGROUND: To the authors' knowledge there are few available data regarding the influence of lymphovascular space invasion, which has been examined separately as two components (lymphatic vessel invasion [LVI] and blood vessel invasion [BVI]), in the metastasis of cervical carcinoma. METHODS: LVI and BVI, which include capillary vessel invasion, were reviewed retrospectively based on the histopathologic slides of 239 women with cervical carcinoma who were treated with radical hysterectomy. The correlation between lymph node and/or ovarian metastases and LVI, BVI, and other histopathologic factors was investigated by multiple logistic regression analysis. The influence of LVI and BVI on survival was examined by Cox regression analysis. RESULTS: The rate of incidence of LVI was higher than that of BVI in all stages of cervical carcinoma (P < 0.0001 for International Federation of Gynecology and Obstetrics Stage IB and Stage II disease and P < 0.05 for Stage III disease). The incidence rate of BVI increased as LVI became more prominent and there was a significant correlation between the two findings (P < 0.0001). BVI was more frequent in adenocarcinoma/adenosquamous carcinoma than in squamous cell carcinoma (P < 0.05). LVI (P < 0.0001) and parametrial invasion (P < 0.0001) were significantly related to lymph node metastasis on multivariate analysis. Conversely, BVI (P < 0.05) and parametrial invasion (P < 0.0025), as well as adenocarcinoma or adenosquamous carcinoma (P < 0.0005), were significantly related to ovarian metastasis on multivariate analysis. With regard to the prognostic significance of these components, it was found that BVI (hazards ratio [HR] = 2.0), ovarian metastasis (HR = 6.5), and lymph node metastasis (HR = 5.5) were significantly related to a poor prognosis in women with cervical carcinoma. CONCLUSIONS: Ovarian metastasis may occur via hematogenous spread of cervical carcinoma. The results of the current study suggest that BVI, including capillary vessels, that is diagnosed separately from LVI using hematoxylin and eosin stained sections may be an important prognostic factor for patients with cervical carcinoma.

Carcinoma, Adenosquamous↗

PubMed2000

Determination of alpha- and beta-trenbolone in bovine muscle and liver by liquid chromatography with fluorescence detection.

A sensitive and rapid high-performance liquid chromatographic screening method is described for the determination of anabolic steroid trenbolone in bovine muscle and liver. Trenbolone was analyzed as alpha- and beta-trenbolone. Samples were extracted with ethyl acetate and cleaned up on a silica solid-phase extraction (SPE) cartridge. Liver samples were cleaned up on a multifunctional SPE cartridge before using a silica SPE cartridge. Analysis of alpha- and beta-trenbolone was performed by reversed-phase high-performance liquid chromatography (HPLC) with a fluorescence detector. The detection limits for this method were estimated to be 0.2 and 1.0 ng/g in bovine muscle and liver, respectively. The mean recoveries spiked in muscle at 2 ng/g and in liver at 10 ng/g were over 80%.

Animals↗

PubMed2000

Recombinant subunit ORF2.1 antigen and induction of antibody against immunodominant epitopes in the hepatitis E virus capsid protein.

A recombinant subunit antigen (ORF2.1), representing the carboxy-terminal 267 amino acids of the 660-amino-acid hepatitis E virus (HEV) capsid protein, was expressed in Escherichia coli and used for the immunisation of rats. Purified antigen formulated with either Aluminium Hydroxide Gel Adjuvant (Alum) or Titermax gave high and equivalent levels of antibody after three doses. Responses to two doses of 15, 75, or 150 microg antigen, formulated with Alum and given at 0 and 4 weeks, were also equivalent by 17 weeks after immunisation. Rats initially developed antibody to a wide range of linear epitopes in the ORF2.1 region, but by 27 weeks the predominant response detected by Western immunoblotting was restricted to the conformational epitope unique to ORF2.1 [Li et al. (1997) Journal of Medical Virology 52:289-300], a pattern that was also observed when comparing acute-phase patient serum samples with serum samples from convalescing patients. Antibody from immunised rats blocked the majority of patients' serum reactivity in enzyme-linked immunosorbent assay against both ORF2.1 (57-92% inhibition) and virus-like particles of HEV produced using the baculovirus system (74-97% inhibition). Together, these results suggest that the ORF2.1 subunit vaccine induces an antibody response against immunodominant, conformational epitopes in the viral capsid, which largely mimics that seen in convalescent patients, who are presumed to be immune to HEV infection.

Adjuvants, Immunologic↗

PubMed2000

Serotype-specific antigen ELISA for detection of Chiba virus in stools.

Chiba virus (CV), a Norwalk-like virus (NLV), was first identified as a cause of oyster-associated outbreak of gastroenteritis that occurred in Chiba prefecture, Japan, in 1987. An enzyme-linked immunosorbent assay (ELISA), based on hyperimmune antisera to recombinant baculovirus-expressed capsid proteins of CV (rCV), was developed to detect CV antigen in stools. No cross-reactions were observed with other enteric viruses including enteroviruses, rotaviruses, astroviruses, or enteric adenoviruses. The ELISA was used to screen 101 stools collected from 16 oyster-associated outbreaks of acute gastroenteritis. Twelve stools (11.9%) from seven outbreaks were positive for CV antigen. Ten rCV ELISA-positive strains were confirmed by RT-PCR and nucleotide sequencing. ELISA-positive strains showed 96-100% nucleotide sequence identity to each other, though they were obtained nine years apart. Phylogenetic analysis demonstrated that all ten strains clustered with the prototype CV in genogroup I viruses. We concluded that the antigen ELISA described in this study is highly type-specific, and that this method should be useful for epidemiological surveys of Chiba virus infections.

Animals↗

PubMed2000

Empty virus-like particle-based enzyme-linked immunosorbent assay for antibodies to hepatitis E virus.

Hepatitis E, an enterically transmitted non-A, non-B hepatitis, is a serious viral infection that occasionally causes large epidemics in developing countries. In developed countries, the disease only appears sporadically due to the transmission routes, and it is considered to be less important. The hepatitis E virus (HEV) cannot grow in cultured cells and no reliable assay system has ever been developed. In addition, the present diagnostic are not perfect, and actual rates of HEV infection may be underestimated. Highly purified empty virus-like particles (VLPs) of HEV have been produced by the use of a recombinant baculovirus vector in insect cells. Using these VLPs as an antigen, an enzyme-linked immunosorbent assay (ELISA) for antibodies to HEV was developed. A panel of 164 sera that were randomized and coded, and sera collected periodically from three patients with hepatitis E were used for the evaluation. The sensitivity of the assay was shown to be equal to or better than that obtained in previous research that used the same serum panel. The ELISA demonstrated that the serum IgM level of the patients was highest at the onset of the clinical illness and then rapidly decreased. In contrast, a high level of circulating IgG antibody titers lasted for more than 4 years. In Japan, a non-endemic country, the prevalence of the IgG class antibody to HEV in healthy individuals was found to range from 1.9% to 14.1%, depending on the geographical area. Only one out of 900 (0.1%) serum samples was IgM-positive. The IgM class antibody to HEV was detected in 10.8% of non-A, non-B, and non-C acute hepatitis patients in northeast China, whereas none of the patients in Korea had the IgM antibody. The ELISA utilizing the VLPs is sensitive and specific in its detection of the IgM and IgG antibodies to HEV. The ELISA is therefore useful for diagnosing HEV infection and for seroepidemiological study of hepatitis E.

Adolescent↗

PubMed2000

Effects of various tocopherol-containing diets on tocopherol secretion into bile.

Gamma-tocopherol is abundant in common vegetable oil, but its concentration in plasma and liver is much lower than that of alpha-tocopherol. Discrimination between different forms of tocopherol is thought to take place via the hepatic alpha-tocopherol transfer protein (alpha-TTP). Gamma-tocopherol, with a low binding capacity to alpha-TTP, is thought to be excreted via the bile. Our previous studies showed that gamma-tocopherol administered with sesame seed exhibits significantly higher concentrations in the plasma and liver of rats than gamma-tocopherol alone. Thus, we attempted to confirm whether a much higher amount of gamma-tocopherol rather than alpha-tocopherol would be secreted in the bile, and whether sesame seed would suppress the secretion of gamma-tocopherol. In one experiment, we examined the concentrations of alpha- or gamma-tocopherol in the plasma, liver, and bile of rats fed diets containing 300 mg/kg of alpha-tocopherol, 300 mg/kg of gamma-tocopherol, or 300 mg/kg each of alpha-tocopherol + gamma-tocopherol, and in the other experiment, we compared the gamma-tocopherol concentrations of rats fed a diet of gamma-tocopherol alone to those of rats fed a gamma-tocopherol + sesame seed diet (each diet contained 300 mg/kg gamma-tocopherol). The bile collection was done over 6 h. The gamma-tocopherol concentration in the bile was markedly lower than that of alpha-tocopherol, paralleling the concentrations in the plasma and liver. Intake of alpha-tocopherol and gamma-tocopherol together further lowered the concentration of gamma-tocopherol in the bile as well as in the plasma and liver, compared to the intake of gamma-tocopherol alone. The gamma-tocopherol concentration in the bile, as well as in the plasma and liver, was markedly higher in the sesame seed-fed group than in the gamma-tocopherol alone group. We found that the concentrations of alpha- or gamma-tocopherol in the bile showed a good correlation with the concentrations of alpha- or gamma-tocopherol in the liver, though the concentrations in the bile were substantially lower than those in the liver. These findings suggest that secretion into the bile is not a major metabolic route of alpha- or gamma-tocopherol.

Animals↗

PubMed2000

Measurement of furancarboxylic acid, a candidate for uremic toxin, in human serum, hair, and sweat, and analysis of pharmacological actions in vitro.

3-Carboxy-4-methyl-5-propyl-2-furanpropionic acid (CMPF), a candidate for uremic toxin, was measured in human hair for examining a possible utility as indicator of renal dysfunction. The serum concentration of CMPF was much higher (32.3 +/- 2.7 microg/ml, n = 17; mean +/- SEM) in uremic patients aged 40-55 years receiving hemodialysis treatment than in healthy younger subjects (3.61 +/- 0.19 microg/ml, n = 22), aged 18-23 years. However, the hair concentration of CMPF tended to be lower in the patients (6.8 +/- 1.7 ng/10 mg hair) than in the healthy younger subjects (15.8 +/- 4.5 ng/10 mg) and was significantly lower than that in the healthy age-matched subjects (22.4 +/- 5.3 ng/10 mg, n = 12), aged 40-47 years. Since CMPF was measurable in the sweat (4.4 +/- 3.7 ng/mg) collected from six out of seven healthy subjects examined, it was suggested that the contribution of sweat to the measurement of CMPF in hair was considerable. The fact that the uremic patients undergoing hemodialysis therapy had less sweat than healthy subjects may explain the lower concentration of CMPF in the patients' hair. The pathophysiological roles of CMPF in the body were attempted to be explored by using excised guinea pig organs, and human platelets and neutrophils. CMPF showed no remarkable effects in the concentration range of < or =10(-4) M except for only slight suppression of spontaneous contracture of guinea pig tenia coli at 10(-4) M. As far as the organs and tissues examined in the present study are concerned, the biological activity of CMPF itself, if any, may be very weak. Precaution should be taken against the delivery of a substance through sweat to hair when a small amount of substance is attempted to be measured in hair by employing a sensitive analytical method.

Adolescent↗

PubMed2000

Standard radial bone mineral density and physical factors in ordinary Japanese women.

To prevent osteoporosis, which is expected to increase in incidence in this rapidly aging society, in recent years bone mineral density (BMD) has frequently been measured as a predisposition index. However, these measurements are made on different sites with different apparatus, and the results are independently studied by different institutions. In our present investigation, to establish the standard radius BMD as determined by dual-energy X-ray absorptiometry (DXA), we carried out a general population survey in 29 municipalities and prefectures on 11,252 locally residing females aged 15 to 83 years (mean, 35.61 +/- 12.85 years). Their YAM (young adult mean) BMD was estimated at 0.664 +/- 0.054 g/cm2, which was almost the same as the figure given in the 1996 version of the diagnostic criteria for primary osteoporosis. We further studied the relationships of BMD to age and physical factors known to be influential to BMD. It was found that BMD was correlated negatively to age and positively to body mass index (BMI). The average values we obtained for age and physique groups appeared to have provided reliable indices for the primary prevention of osteoporosis.

Adolescent↗

PubMed2000

PCDDs/DFs emissions from crematories in Japan.

Concentrations of PCDDs and PCDFs in emission gases from 10 crematories were measured. The relationship between PCDDs/DFs and several factors such as structure, equipment and operational state of the crematory is discussed. Furthermore, emission of PCDDs/DFs from all crematories in Japan is estimated. The following results are obtained: (1) total concentration of PCDDs/DFs was 2.2-290 ng/N m3, whose TEQ concentration was 0.0099-6.5 ng TEQ/N m3; (2) total concentration of PCDFs was higher than that of PCDDs; (3) T4CDFs was the highest in the homologue pattern and 2,3,7,8-T4CDF was the highest in the isomer pattern; (4) emission of PCDDs/DFs was the largest in the first 20 min of cremation; (5) concentration of PCDDs/DFs was related to the existence of a secondary combustion chamber and a dust collector, and the ratio of the numbers of main and secondary combustion chambers; (6) total emission of PCDDs/DFs from crematories in Japan was estimated to be 8.9 g TEQ/yr.

Age Factors↗

PubMed2000

Postoperative results for cholesteatoma in children.

OBJECTIVES: to review the postoperative results for cholesteatoma in children. MATERIALS: 32 ears with acquired cholesteatoma in children operated on by a single surgeon between 1987 and 1995 and followed up more than 2 years. The mean follow-up period was 5.4 years. RESULTS: a one-stage operation was performed in seven ears (21.9%) and preplanned stage operation in 25 ears (78.1%). In the first operation, closed tympanoplasty was performed in 31 ears (96.9%) and open tymapanoplasty in one ear (3.1%). During the second stage operation, residual cholesteatoma was found in 16 ears (64.0%). Recurrent cholesteatoma was detected in 19.4% of ears treated with closed tympanoplasty. The mean postoperative air conduction hearing level was within 20 dB in 12.5%, 30 dB in 40.6% and 40 dB in 78.1%. The hearing results of type III tympanoplasty was better than those of type IV tympanoplasty. CONCLUSIONS: preplanned stage tympanoplasty is safer because of the high risk of recurrent and residual cholesteatoma. Surgical methods should be selected flexibly in individual cases depending upon cavity size, eustachian tube function and hearing level. Cholesteatoma in children should be operated on while stapes is present.

Adolescent↗

PubMed2000

Monte Carlo simulation of gamma-ray response functions for a proportional counter used for neutron measurement

It is often required in neutron calibration fields to determine the dose of gamma-rays produced in a neutron source and in the surroundings, because some neutron detectors are sensitive both to neutrons and gamma-rays. As a first step estimating neutron and gamma-ray energy spectra and fluences simultaneously in a neutron field, the gamma-ray response function for a 3He proportional counter was calculated using EGS4/PRESTA code. In the simulation, the gas multiplication factor, which depends on the detection position in the gas region along an anode wire, was taken into account to obtain the precise response function. For comparison, we measured response functions using different reference gamma-ray sources such as 241Am, 137Cs, and 60Co, which were located vertically 55 mm away from the center of the anode wire. Calculated response functions agreed well with experimental ones. Monte Carlo code EGS4 is thus useful for the simulation of gamma response functions for neutron counters.

Journal Article↗

PubMed2000

Novel nitric oxide and superoxide generation inhibitors, persenone A and B, from avocado fruit.

One known, (2R)-(12Z,15Z)-2-hydroxy-4-oxoheneicosa-12,15-dien+ ++-1-yl acetate (1), and two novel compounds, persenone A (2) and B (3), have been isolated from avocado fruit (Persea americana P. Mill), as inhibitors of superoxide (O(2)(-)) and nitric oxide (NO) generation in cell culture systems. They showed marked inhibitory activities toward NO generation induced by lipopolysaccharide in combination with interferon-gamma in mouse macrophage RAW 264.7 cells. Their inhibitory potencies of NO generation (1, IC(50) = 3.6; 2, IC(50) = 1.2; and 3, IC(50) = 3.5 microM) were comparable to or higher than that of a natural NO generation inhibitor, docosahexaenoic acid (DHA; IC(50) = 4.3 microM). Furthermore, compounds 1-3 and DHA markedly suppressed tumor promoter 12-O-tetradecanoylphorbol-13-acetate-induced O(2)(-) generation in differentiated human promyelocytic HL-60 cells (1, IC(50) = 33.7; 2, IC(50) = 1.4; 3, IC(50) = 1.8; and DHA, IC(50) = 10.3 microM). It is notable that they were found to be suppressors of both NO- and O(2)(-)-generating biochemical pathways but not to be radical scavengers. The results indicate that these compounds are unique antioxidants, preferentially suppressing radical generation, and thus may be promising as effective chemopreventive agent candidates in inflammation-associated carcinogenesis.

Animals↗

PubMed2000

Echocardiographic evaluation of the ductal morphology in patients with refractoriness to lipo-prostaglandin E1 therapy.

BACKGROUND: Lipo-prostaglandin (PG)E1 is effective at lower doses and has fewer side effects than PGE1-cyclodextrin (CD). Previous studies, however, have suggested that some patients show refractoriness to lipo-PGE1 in the course of treatment. The present paper examines: (i) whether such cases can be predicted by examining the ductal morphology before and 24 h after the start of lipo-PGE1 infusion; and (ii) whether PGE1-CD dilates the ductus arteriosus in patients with refractoriness to lipo-PGE1. METHODS: The ductal morphology was evaluated with two echo indices, such as minimal and minimal plus maximal intraluminal diameters of the ductus. Two-dimensional echocardiography was performed in 24 patients with ductus-dependent congenital heart disease. The two echo indices were measured before and 24 h after lipo-PGE1 infusion and also at least twice per week until surgery. RESULTS: In 19 of 24 patients, ductal patency was maintained until surgical treatment (group A). The remaining five patients (21%) showed ductal closure during the course of the lipo-PGE1 therapy (group B). There were no significant differences between the two groups, in either the maximal or minimal diameters, which were examined before and 24 h after treatment. In the five patients of group B, lipo-PGE1 was replaced with a relatively high dosage of PGE1-CD (50-100 ng/kg per min), resulting in good ductal patency until surgery. CONCLUSIONS: Patients with refractoriness to lipo-PGE1 therapy could not be predicted from initial intraluminal diameters of the ductus using echocardiography. Therefore, serial echocardiographic examinations are important to detect early findings of ductal closure. In addition, PGE1-CD is still useful as back-up therapy in such patients.

Alprostadil↗

PubMed2000

Older boys benefit from higher initial prednisolone therapy for nephrotic syndrome. The West Japan Cooperative Study of Kidney Disease in Children.

BACKGROUND: A long course of the initial prednisolone therapy has been shown to be more effective than standard-course therapy in reducing relapse rates in children with idiopathic nephrotic syndrome, but it is commonly accompanied by corticosteroid toxicities. There has been no study on prednisolone dosage for the effective treatment of nephrotic syndrome. METHODS: Sixty-eight children (42 boys and 26 girls) with an initial attack of nephrotic syndrome were randomly allocated into two different long-course treatment groups. Patients in Group 1 received a daily prednisolone dose of 60 mg/m2 for six weeks, followed by an alternate-day dose of 40 mg/m2 for six weeks. Patients in Group 2 had a daily dose of 40 mg/m2 instead of 60 mg/m2. RESULTS: Four children in each group did not respond within six weeks. Group 1 was associated with a significantly earlier response but more frequent corticosteroid toxicities than Group 2. Boys in Group 1 had a higher rate of sustained remission than boys in Group 2 (P = 0.0073), especially boys four years old or more (P = 0.0027), but girls did not show a significant difference (P = 0.863). Boys four years old or more in Group 1 had a course of frequent relapsing less often than those in Group 2 (2 of 13 vs. 6 of 8, P = 0.0075). CONCLUSION: These findings indicate that efficient prednisolone doses may vary between sexes and ages, and that a higher initial prednisolone therapy may be of greater benefit to older boys.

Adolescent↗

PubMed2000

Serum concentrations of estradiol and dehydroepiandrosterone sulfate and soy product intake in relation to psychologic well-being in peri- and postmenopausal Japanese women.

The effect of steroid hormones, such as estrogen and dehydroepiandrosterone (DHEA) on psychologic well-being of women has been suggested. Dietary estrogen may also affect psychologic status. We examined the cross-sectional relationships of serum concentrations of estradiol (E2) and DHEA sulfate (DHEAS) and dietary intake of soy products to psychologic status measured using the Center for Epidemiologic Studies Depression Scale (CES-D) and General Health Questionnaire (GHQ)-12 scales in 86 peri- and postmenopausal Japanese women. Intake of soy products and other dietary components was estimated from a validated semiquantitative food frequency questionnaire. A fasting blood sample was obtained from each woman to measure serum concentrations of E2 and DHEAS. Serum DHEAS was significantly inversely correlated with CES-D scale (r = -.22, P = .04) and GHQ-12 scale (r = -.27, P = .01). Soy product intake was significantly inversely correlated with CES-D scale (r = -.22, P = .04). Neither serum E2 concentration nor the ratio of serum E2 to sex hormone-binding globulin (SHBG) was associated with any of the psychologic measurements. These data suggest a possibility that endogenous DHEA sulfate and dietary soy may modulate psychologic well-being of peri- and postmenopausal women.

Dehydroepiandrosterone Sulfate↗

PubMed2000

Effects of vestibular cerebellum lesion on motion sickness in rats.

The importance of the vestibular apparatus in the development of motion sickness is widely accepted, although the role of the vestibular cerebellum remains controversial. We examined the effects of vestibular cerebellum lesion on the development of motion sickness in rats. Rats do not vomit, but the behaviour known as "pica", the eating of non-nutritive substances, such as kaolin, can be used as an index of motion sickness. A 2 h load of hypergravity induced pica in rats, indicating that they suffered from motion sickness. Pica was induced by hypergravity load even after surgical lesion to the bilateral cerebellar flocculus or to the cerebellar vermis. We concluded that the vestibular cerebellum was not essential in the development of motion sickness in rats.

Animals↗

PubMed2000

Cholinergic influence on vestibular stimulation-induced locus coeruleus inhibition in rats.

In our previous study, caloric stimulation (CS) of the vestibular apparatus inhibited noradrenergic neuronal activity in the locus coeruleus (LC) in urethane-anaesthetized rats. Therefore, the inhibition of LC noradrenergic neurons is involved in vestibulo-autonomic responses. Since motion sickness can be cured by scopolamine, cholinergic neuron system may also be involved in vestibulo-autonomic responses. The present study examined the effects of intracerebroventricular injection of ethylcholine mustard aziridinium ion (AF64A), a presynaptic cholinergic neurotoxin, on CS-induced LC inhibition. In AF64A-treated rats, the CS-induced LC inhibition was less pronounced than in normal rats. In a subsequent series of experiments, the intravenous injection of scopolamine blocked the CS-induced LC inhibition. These findings suggest that central cholinergic neurons are associated with noradrenergic neuronal inhibition during the vestibulo-autonomic reflex.

Animals↗

PubMed2000

Effects of amygdala or hippocampus lesion on hypergravity-induced motion sickness in rats.

We examined the effects of amygdala lesion (AL) or hippocampal lesion (HL) on hypergravity-induced motion sickness in rats. Rats do not vomit, but the behavior known as pica, the eating of non-nutritive substances such as kaolin, can be used as an index of motion sickness. In the present study, hypergravity-induced kaolin intake and apomorphine-induced kaolin intake were measured before and after brain lesions. After AL, hypergravity-induced kaolin intake and the ratio of the hypergravity- to apomorphine-induced kaolin intakes were decreased. These results indicate that AL suppressed motion sickness more than pica behavior itself, suggesting that the amygdala plays an important role in the development of motion sickness in rats. Conversely, after HL, hypergravity-induced kaolin intake was increased, as was the ratio of the hypergravity- to apomorphine-induced kaolin intakes. These results indicate that HL aggravates motion sickness induced by hypergravity in rats, suggesting that the hippocampus counteracts motion sickness.

Amygdala↗