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K Ito

Publications and source records attributed to K Ito.

At least 289 records · Page 16Linked to original sources
PubMed2001

[Estimation of radiation exposed area by the nuclear accident occurred at Tokai village using ESR measurements of household sugar].

The area of radiation exposure by the nuclear accident occurred at Tokai village in 1999 was estimated by the ESR measurement of 95 household sugar samples collected from the accident area. These samples were roughly classified into three types of sugar, fine white sugar, fine brown sugar and coarse brown sugar. The control fine white sugar showed no radical in the ESR spectrum, while those of fine brown sugar and coarse brown sugar showed the presence of a small amount of radicals. It was also shown that, among these three kinds of sugar, the radical concentration of fine white sugar sampled from wooden houses at the area similar to each other did not vary much with the samples, while those of fine brown sugar and coarse brown sugar varied to a considerable extent. Thus, the fine white sugar is considered to be more suitable for the estimation of the level of radiation exposure. The radical concentration of each fine white sugar sample was plotted against the distance from the site of the nuclear accident with a correction of the difference in the shielding effect between concrete houses and wooden houses. The samples obtained at more than 2 km north of the site of nuclear accident showed no ESR spectral signal to a detectable extent. On the other hand, the ESR spectra were observed from the samples obtained within 10 km south and 4 km west of the accident site. These results suggest that the radiation exposure by the contaminant blown by the northeast wind blowing on the day of the accident may occur at the south and west areas.

Electron Spin Resonance Spectroscopy↗
PubMed2001

[The roles of pharmacists on prior review of clinical trials].

A prior review system for clinical trials was introduced into The University of Tokyo Hospital in March 1999, for the purpose of supporting the Institutional Review Board (IRB). In this study, we investigated the effect of this system on IRB, and evaluated roles of pharmacists involved in utilizing this prior review system. An average period from the acceptance of regular application of each protocol to the approval of IRB was 1.7 months, and the period was significantly shorter than that before the introduction of this system (2.3 months). On the other hand, the number of instructions given to applicants increased to be 2.8 times before the introduction of this system, suggesting the improvement of the quality of this prior review system. In the prior review, the number of instructions pointed out from pharmacists concerning pharmacokinetics, pharmacodynamics, drug-interactions, adverse reactions, and the other matters related to investigational drugs was greater than that from doctors or nurses. According to the results of the surveys for doctors, nurses, and other clerical employees, pharmacists were indicated to review from a pharmaceutical point of view and their review was found to be very important. In conclusion, the prior review system was considered to be useful for the rational practice of clinical trials and pharmacists were recognized to be indispensable as reviewers on the prior review.

Clinical Trials as Topic↗
PubMed2001

Extracellular soluble polysaccharide (ESP) from Aspergillus kawachii improves the stability of extracellular beta-gluocosidases (EX-1 and EX-2) and is involved in their localization.

Aspergillus kawachii produces two extracellular beta-glucosidases (EX-1 and EX-2) and one cell-wall-bound beta-glucosidase (CB-1), all of which are derived from the same bglA gene. Extracellular beta-glucosidases (EX-1 and EX-2) are stable in the crude solution form, but become unstable in the purified form under moderate conditions (pH 5.0 and 37 degrees C). Purified extracellular beta-glucosidases can bind to a mycelial cell wall fraction, even though these enzymes are released into the medium under solid culture conditions. A. kawachii produces an extracellular soluble the beta-glucosidases over the pH range of 3.0-7.0 and at temperatures below 50 degrees C. ESP directly interacted with the purified extracellular beta-glucosidases but did not affect the K(m) values of these enzymes. Moreover, ESP inhibited the adsorption of purified extracellular beta-glucosidases to the cell wall fraction and extracted them from it. These results that ESP plays important roles in the stability and localization of extracellular beta-glucosidases. ESP from A. kawachii directly binds to the enzymes and releases them to the medium from the cell wall layer and then stabilizes them.

Journal Article↗
PubMed2001

Cloning and analysis of valerophenone synthase gene expressed specifically in lupulin gland of hop (Humulus lupulus L.).

Resin and essential oil derived from hop (Humulus lupulus L.) cones are very important compounds for beer brewing, and they specifically accumulate in the lupulin gland of hop cones. In order to identify the genes responsible for the biosynthetic pathway of these compounds and use the identified genes for hop breeding using Marker Assisted Selection and transformation techniques, genes expressed specifically in the lupulin gland were cloned and sequenced. One of them was suggested to be similar to the chalcone synthase gene from the DNA sequence. The translation product of the gene had the activity of valerophenone synthase, which catalyzes a part of the synthesis reaction of alpha-acid and beta-acid. Northern analysis showed that the valerophenone synthase gene seemed to be expressed specifically in the lupulin gland.

Acyltransferases↗
PubMed2001

Femoroacetabular impingement and the cam-effect. A MRI-based quantitative anatomical study of the femoral head-neck offset.

We have observed damage to the labrum as a result of repetitive acetabular impingement in non-dysplastic hips, in which the femoral neck appears to abut against the acetabular labrum and a non-spherical femoral head to press against the labrum and adjacent cartilage. In both mechanisms anatomical variations of the proximal femur may be a factor. We have measured the orientation of the femoral neck and the offset of the head at various circumferential positions, using MRI data from volunteers with no osteoarthritic changes on standard radiographs. Compared with the control subjects, paired for gender and age, patients showed a significant reduction in mean femoral anteversion and mean head-neck offset on the anterior aspect of the neck. This was consistent with the site of symptomatic impingement in flexion and internal rotation, and with lesions of the adjacent rim. Furthermore, when stratified for gender and age, and compared with the control group, the mean femoral head-neck offset was significantly reduced in the lateral-to-anterior aspect of the neck for young men, and in the anterolateral-to-anterior aspect of the neck for older women. For patients suspected of having impingement of the rim, anatomical variations in the proximal femur should be considered as a possible cause.

Acetabulum↗
PubMed2001

Papillary carcinoma occurring within an adenomatous goiter of the thyroid gland in Cowden's disease.

Cowden's disease is an autosomal dominant disorder characterized by multiple benign and malignant neoplastic lesions involving many organs. The presence of characteristic cutaneous lesions is crucial for the diagnosis. Thyroid disease is a major extracutaneous manifestation of this disease; however, the histologic characteristics have not been described in detail. We report a case of thyroid tumor associated with Cowden's disease. Grossly, the tumor showed a multinodular appearance, like an adenomatous goiter. Microscopically, it consisted of follicular adenomas with a trabecular pattern. Some of the nodules had a second component resembling papillary carcinoma. This was thought to be a unique histological feature not described previously, and might be specific to thyroid tumor associated with Cowden's disease.

Adenoma↗
PubMed2001

Ultrasonographic features of parathyroid carcinoma.

Although several authors have reported single cases illustrative of some ultrasonographic characteristic of parathyroid carcinoma, the value of ultrasonography for diagnosing this entity remains to be determined. The purpose of our study was to investigate the ultrasonographic features of parathyroid carcinoma in a large number of cases. We assessed the shape, contour, echogenicity, and depth-width (DW) ratio of 16 parathyroid carcinomas and 61 parathyroid adenomas. Ultrasonography showed that parathyroid carcinomas tend to be large, inhomogeneous, hypoechoic masses with lobulated contours. In contrast, parathyroid adenomas were small, homogeneous, hypoechoic masses with smooth borders. The mean (range) DW ratios for parathyroid carcinomas were 1.21 (0.91-2.5) and 0.64 (0.33-1.47) for adenomas; the difference was statistically significant (p<0.0001). The DW ratio was > or =1 in 15 (94%) of the 16 cases of carcinoma, whereas only 3 (5%) of the 61 adenomas had a similar ratio. Ultrasonographic examination is useful not only for preoperative localization but also for differentiating parathyroid carcinoma from adenoma. Parathyroid tumors with irregular margins, inhomogeneous echogenicity, and a DW ratio > or =1 are likely to be malignant.

Adenoma↗
PubMed2001

Effectiveness of an antiplatelet agent for coronary artery ectasia associated with silent myocardial ischemia.

A 74-year-old Japanese male was referred to our hospital because of an abnormal electrocardiogram. The electrocardiogram revealed tall P waves in leads II, III, and aV(F). Echocardiography disclosed hypokinesis extending from the anteroseptal region to the apex. Iodine-123 15-(p-iodophenyl)-3-(R,S)-methylpentadecanoic acid (123-BMIPP) scintigraphy revealed reduced uptake from the anteroseptal region to the apex. Coronary arteriography demonstrated diffuse dilatation of the right and left coronary arteries without organic stenosis, and left ventriculography showed hypokinesis at the same area. Furthermore, the coronary flow reserve in the left anterior descending artery was decreased. He was treated with an antiplatelet agent. Ten months later, the left ventriculography, 123I-BMIPP scintigraphy findings and coronary flow reserve were normalized. These findings demonstrate that antiplatelet therapy may be useful in the preservation of left ventricular function in patients with coronary artery ectasia.

Aged↗
PubMed2001

A comparative study on the integration of exogenous DNA into mouse, rat, rabbit, and pig genomes.

Transgenic mammals, from small laboratory rodents to domestic animals, have been successfully produced to date, but their production efficiency within or across species has been variable. This is probably due to the differences in the type of injected DNA and/or technical procedures employed in each laboratory, as well as the reproductive characteristics of the species. Here we report the direct comparison of the efficiencies of producing transgenic mice, rats, rabbits and pigs by one technician using a fusion gene composed of the bovine alpha S1-casein promoter and human growth hormone (hGH) gene. Before the fusion gene was injected into the zygotes, high magnitude centrifugation to visualize the pronuclei was necessary for all of the pig zygotes and one-third of the rabbit zygotes, but not for mouse and rat zygotes. Post-injection survival of the mouse zygotes (67.1%) was lower than those of the rat, rabbit and pig zygotes (89.6 to 100%). The volume change of the pronucleus following DNA injection was the lowest in mice (50% increase), moderate in rabbits (148% increase), and the most prominent in rats (238% increase). The data from only 1 pig zygote indicated a 22% increase in the pronucleus volume by DNA injection. The PCR analyses of the tail DNA of new born offspring indicated that 0.8% (4/493), 4.8% (22/463), 0.8% (3/367) and 0.9% (2/221) of the injected eggs in mice, rats, rabbits and pigs, respectively, developed into transgenic offspring. Some of the founder animals in all four species expressed the transgene in the mammary gland which was confirmed in hGH mRNA by RT-PCR and/or hGH peptide in Witch's milk with ELISA. These results suggest that the maximum volume of DNA solution injectable into the pronucleus is a possible factor explaining the species differences in the production of transgenic animals.

Animals↗
PubMed2001

Production of transgenic rats using young Sprague-Dawley females treated with PMSG and hCG.

The aim of this study was to examine the effects of gonadotrophin treatments on estrus synchronization and superovulation in young Sprague-Dawley (SD) rats that had not yet exhibited defined estrus cycles (5 to 7 weeks old), and to produce transgenic rats using these females as embryo donors and recipients. In Experiment 1, female rats were injected with PMSG and hCG (12.5, 25, 50 and 100 IU/kg each) and were mated with stud males. The reproductive performance of young rats were highest when PMSG and hCG at doses of 25 IU/kg each were injected (delivery rate 87.5%, nursing rate 92.9%). In Experiment 2, female rats were injected with PMSG and hCG (100, 150 and 300 IU/kg each) to induce superovulation. More eggs were recovered from the rats injected with PMSG and hCG at 150 and 300 IU/kg than from those treated with 100 IU/kg (33.4 and 41.3 vs. 13.3 eggs per female, respectively; p < 0.05). In Experiment 3, pronuclear-stage zygotes from 150 IU/kg PMSG/hCG-treated rats were used for microinjection of the fusion gene of bovine alpha S1-casein gene promoter and human growth hormone gene (2.8 kb), and the microinjected zygotes were transferred into the oviduct ampullae of the 25 IU/kg PMSG/hCG-treated rats. Seventeen transgenic rats were obtained from the 334 DNA-injected zygotes (5.1%). These results indicate that recipients and embryo donors for the production of transgenic rats can be prepared by the appropriate PMSG and hCG treatments of young SD rats, regardless of their estrus stages.

Animal Husbandry↗
PubMed2001

Attachment of human periodontal ligament cells to enamel matrix-derived protein is mediated via interaction between BSP-like molecules and integrin alpha(v)beta3.

BACKGROUND: Although enamel matrix-derived protein (EMD) can stimulate attachment of human periodontal ligament (HPDL) cells to the root surface, the biological mechanism of this phenomenon is unclear. The purpose of this study was to determine which molecules in EMD are involved in the attachment of HPDL cells, and which types of integrins on the cell surface mediate the interaction between the cells and EMD. METHODS: HPDL explants were obtained from tooth surfaces extracted from 4 individuals, and cells taken from the individual explants were separately harvested and subcultured through as many as 5 passages. Cells were incubated on EMD-coated culture plates with and without neutral antibodies for integrins or RGD-sequence blocking peptides and stained with toluidine blue. Proteins in EMD that were able to induce cell attachment were identified by incubating sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) replicas with HPDL cells; the cell-binding regions were detected by staining the cells with toluidine blue. Characteristics of the cell-binding proteins in the EMD were identified by Western blot analysis. RESULTS: It was shown that anti-alpha(v)beta3 antibody and GRGDSP peptide markedly reduced attachment of HPDL cells to EMD. When the cells were incubated with SDS-PAGE replicas, distinct cell attachment was observed at a molecular mass of approximately 55 kDa. The cell-binding ability of this protein was completely blocked by treatment with anti-alpha(v)beta3 antibody or GRGDSP peptide. In the Western blot analysis, the 55 kDa protein was recognized by anti-bone sialoprotein (BSP) antibody as a single band. CONCLUSIONS: Our study provides the first evidence that the attachment of HPDL cells to EMD can be mediated by interaction between a BSP-like molecule and integrin alpha(v)beta3 on the cell surface.

Amino Acid Sequence↗
PubMed2001

Clinical application of a new compact computed tomography system for evaluating the outcome of regenerative therapy: a case report.

BACKGROUND: The limitations of conventional 2-dimensional (2-D) radiographs have been emphasized in many studies. Because the image is a 2-D map of the 3-dimensional (3-D) tooth and periodontal tissue, these structures may be superimposed on each other. Recently, 3-D image analysis by computed tomography (CT) was introduced to dentistry, but it has been used only rarely in the periodontal field. METHODS: The purpose of this case report was to introduce the clinical application of a newly developed, compact computed tomography system for evaluating the outcome of regenerative therapy in an adult patient with periodontitis (male, aged 55 years). To evaluate the bone defects including furcation involvement, we took an intraoral radiograph and performed CT scanning on tooth #19. We recorded a number of clinical parameters at the time of surgery. We compared the images of the bone defect obtained by CT images and the conventional radiograph with the true bone defect morphology at the surgical site. RESULTS: One year after the periodontal surgery, we again took CT scans and a conventional radiograph, and the new images of the bone defect were compared and evaluated. The new CT images were reconstructed for 3-D evaluation and compared with those taken before surgery. The CT provides 3-D images of excellent quality for evaluating the morphology of the periodontal bone defect and furcation involvement. CONCLUSIONS: We consider that CT is a useful aid in periodontal examination and diagnosis, and in the prediction and evaluation of periodontal treatment outcomes.

Alveolar Bone Loss↗
PubMed2001

Eradication of foot and mouth disease in Japan.

An outbreak of foot and mouth disease (FMD) was recorded in Japan in the spring of 2000, the first for ninety-two years. Between 25 March and 11 May, four farms were infected. However, the disease was eradicated without resorting to vaccination, through a campaign of culling, movement control of cloven-hoofed animals in areas surrounding infected premises, and intensive clinical and serological surveillance. Japan regained FMD-free status by the end of September 2000. The authors describe the nature of the outbreaks, the eradication measures implemented, and the clinical and serological surveillance methods used. The possible sources of infection are also examined. Finally, the direct and indirect economic losses are presented.

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

The temperature-dependent modulation of an inhibitory circuit in hippocampal slices as revealed by a population spike recording is mediated by extracellular adenosine.

We examined the effects of temperature on excitatory synaptic transmission and the recurrent inhibitory loop in CA1 neurons in guinea pig hippocampal slices. Increasing the temperature of the perfusing medium from 30 to 49 degrees C resulted in attenuation of both the amplitude of the synaptically evoked CA1 population spikes and the paired-pulse inhibition (PPI) of the spikes. A bath application of 2 microM picrotoxin, a gamma-aminobutyric acid receptor antagonist, did not affect the amplitude of the CA1 population spikes, but it significantly reduced PPI during the early heating phase (30-32 degrees C). In contrast, the application of 1 mM theophylline or 50 microM 8-phenyltheophylline, a selective adenosine A1 receptor antagonist, resulted in significant augmentation of the PPI during the early phase of hyperthermia (30-34 degrees C) and a significant increase in the amplitude of the CA1 population spikes at higher temperatures (34-43 degrees C). These results suggest that increased activation of adenosine A1 receptors in response to a temperature increase depresses not only excitatory synaptic responses, but also the strength of the inhibitory circuit in CA1 neurons. Furthermore, hyperexcitability of CA1 pyramidal neurons was seen in the middle of the heating range (34-38 degrees C), excitatory responses still being present, but the strength of the inhibitory circuit significantly reduced.

Animals↗
PubMed2001

Three-dimensional portography using multislice helical CT is clinically useful for management of gastric fundic varices.

OBJECTIVE: This study seeks to evaluate three-dimensional (3D) helical CT portography as a tool for examining patients with gastric fundic varices. SUBJECTS AND METHODS: We compared 3D helical CT portography and conventional angiographic portography in 30 consecutive patients with gastric fundic varices. We assessed whether 3D helical CT portography is useful in selecting patients and in evaluating the results of balloon-occluded retrograde transvenous obliteration. RESULTS: Three-dimensional helical CT portography simultaneously depicted second or third branches of the intrahepatic portal vein and provided images of entire portosystemic collaterals. On 3D helical CT portography, gastric fundic varices were seen in 30 patients (100%), left gastric veins in 19 (63%), posterior gastric veins or short gastric veins in 28 (93%), gastrorenal shunts in 27 (90%), paraumbilical veins in three (10%), and inferior phrenic veins in two patients (7%). Findings of 3D helical CT portography and conventional angiographic portography were in close agreement. However, in four patients, posterior gastric veins or short gastric veins were not seen on conventional angiographic portography images of the spleen, but they were clearly revealed on 3D helical CT portography. Treatment was successful in all patients except one. Three-dimensional helical CT portography could easily evaluate therapeutic results. CONCLUSION: Three-dimensional helical CT portography proved so effective that it can be considered a less invasive alternative than conventional angiographic portography in assessing portosystemic collaterals. CT portography is useful in selecting candidates from patients with gastric fundic varices for retrograde transvenous obliteration and also in evaluating therapeutic results.

Adult↗
PubMed2001

Detection of malignant hepatic tumors: comparison of gadolinium-and ferumoxide-enhanced MR imaging.

OBJECTIVE: The purpose of our study was to compare how well gadolinium-enhanced and ferumoxide-enhanced MR imaging reveal malignant hepatic tumors. SUBJECTS AND METHODS: Both gadolinium-enhanced and ferumoxide-enhanced MR imaging were separately performed in 53 patients with a total of 87 malignant hepatic tumors (57 hepatocellular carcinomas, 28 metastases, two cholangiocarcinomas). Thirty-one of the 53 patients had hepatic cirrhosis. Images were reviewed by three independent off-site observers. Observer performance was evaluated by means of sensitivity, specificity, and receiver operating characteristic curve analyses. RESULTS: Gadolinium-enhanced MR imaging outperformed ferumoxide-enhanced MR imaging in sensitivity (81% versus 62%, p < 0.01) for malignant-tumor detection. Specificity was comparable (94%) between the two types of MR imaging. Area under receiver operating characteristic curve (A(z)) value was significantly higher with gadolinium-enhanced MR imaging than with ferumoxide-enhanced MR imaging in patients overall (A(z) = 0.896 versus 0.805, p < 0.001), in patients with cirrhosis (A(z) = 0.907 versus 0.807, p < 0.001), and in patients without cirrhosis (A(z) = 0.899 versus 0.834, p < 0.01). The superiority was enhanced in the subset of patients with cirrhosis. CONCLUSION: Gadolinium-enhanced MR imaging outperforms ferumoxide-enhanced MR imaging in revealing malignant hepatic tumors. Gadolinium-enhanced MR imaging is recommended, particularly for patients with cirrhosis.

Aged↗