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N Takeda

Publications and source records attributed to N Takeda.

At least 37 records · Page 2Linked to original sources
PubMed2004

Cross-reactivity among sapovirus recombinant capsid proteins.

Sapovirus (SaV), a member of the genus Sapovirus in the family Caliciviridae, is an agent of human and porcine gastroenteritis. SaV strains are divided into five genogroups (GI-GV) based on their capsid (VP1) sequences. Human SaV strains are noncultivable, but expression of the recombinant capsid protein (rVP1) in a baculovirus expression system results in the self-assembly of virus-like particles (VLPs) that are morphologically similar to native SaV. In this study, rVP1 constructs of SaV GI, GII, and GV strains were expressed in a baculovirus expression system. The structures of the GI, GII, and GV VLPs, with diameters of 41-48 nm, were morphologically similar to those of native SaV. However a fraction of GV VLPs were smaller, with diameters of 26-31 nm and spikes on the outline. This is the first report of GII and GV VLP formation and the first identification of small VLPs. To examine the cross-reactivities among GI, GII, and GV rVP1, hyperimmune rabbit antisera were raised against Escherichia coli-expressed GI, GII, and GV N- and C-terminal VP1. Western blotting showed the GI antisera cross-reacted with GV rVP1 but not GII rVP1; GII antisera cross-reacted weakly with GI rVP1 but did not cross-react with GV rVP1; and GV antisera reacted only with GV rVP1. Also, hyperimmune rabbit and guinea pig antisera raised against purified GI VLPs were used to examine the cross-reactivities among GI, GII, and GV VLPs by an antigen enzyme-linked immunosorbent assay (ELISA). The ELISA showed that the GI VLPs were antigenically distinct from GII and GV VLPs.

Animals↗
PubMed2004

Human Kluver-Bucy syndrome following acute subdural haematoma.

We present a rare case of complete human Kluver-Bucy syndrome (KBS) following recovery from transtentorial herniation caused by acute subdural haematoma (ASDH). A 17-year-old right-handed high school boy got into stupor within five minutes after 3-rounds of sparing at boxing. Emergency computed tomographic (CT) scan showed right cerebral hemispheric ASDH, which was evacuated following intentional decompressive craniectomy. After recovery of consciousness, he developed emotional changes (placidity with loss of normal fear and anger), psychic blindness, aberrant sexual behaviour, excessive oral tendencies, increased appetite, and hypermetamorphosis in order of mention, which were observed with waxing and waning from 17th to 28th hospital day. Peri-operative CT scaning and magnetic resonance imaging showed lesions of the right temporal lobe and right-dominant orbitofrontal regions including bilateral rectal and medial orbital gyri, and the intact left temporal lobe. Two pathogeneses can be thought of and the whole picture of KBS following ASDH can arise even though one (left in this case) temporal lobe is preserved, 1) in which associated orbitofrontal lesions of the frontal lobes may correlate with occurrence of KBS, or 2) cerebral blood hypoperfusion of both temporal lobes due to increased intracranial pressure and/or compression of both posterior cerebral arteries at the edge of the tentorium cerebelli occurs.

Adolescent↗
PubMed2004

Ruptured de novo intracranial aneurysms.

OBJECTIVE: We describe the actual state of ruptured de novo intracranial aneurysms to contribute to a guideline of follow-up for the patients with treated intracranial aneurysm. METHODS: The authors retrospectively investigated 12 cases drawn from 483 consecutive cases of aneurysmal subarachnoid hemorrhage at our institute over a period of 22 years, in which a previously undemonstrated (hence "de novo") intracranial saccular aneurysm formed and ruptured after successful treatment of a prior aneurysm. FINDINGS: The 12 cases constitute 2.5% of the 483 patients who left our hospital alive. Eleven cases were females and one was a male with a mean age of 55.7 years (range 29-75) at the first subarachnoid haemorrhage (SAH) and an interval between the first and the second rupture of 10.7 years (range: 2.6-23.8, standard deviation: 6.86, 95% confidence interval: 6.39-15.1). Four cases did not have risk factors such as hypertension, family history, smoking, multiple aneurysms, and moyamoya disease. None of these ruptured de novo aneurysms was at the same location as the original lesion. One-third (4 cases) of the de novo lesions in our series were found on the opposite side to each prior lesion. INTERPRETATION: For not only young but also elder patients with a treated aneurysm (from the fifth decade to the sixth), especially for women, late angiography or alternative modalities of less-invasive examination should be considered. To detect de novo intracranial aneurysms before rupture, the search for a de novo aneurysm should be performed within 6.39 years after a previous examination that shows an aneurysm to be nonexistent, in view of the 95% confidence interval of the mean time to de novo aneurysmal rupture (6.39-15.1 years). If applied this survey, 75% (8 cases of 12 cases) of our de novo aneurysms would be detected before rupture.

Adult↗
PubMed2004

Detection of norovirus and sapovirus infection among children with gastroenteritis in Ho Chi Minh City, Vietnam.

This report describes norovirus (NoV) and sapovirus (SaV) infections in hospitalized children with acute sporadic gastroenteritis in Ho Chi Minh City, Vietnam. Stool specimens collected between December 1999 and November 2000 were examined for NoV and SaV using reverse transcription-PCR and phylogenetic analysis. NoVs were detected in 72 of 448 rotavirus-negative specimens, counted as part of an overall annual detection rate of 5.4% (72 of 1,339 children). This included four NoV genogroup I (GI) strains and 68 NoV GII strains. Only one SaV GI strain was detected in the rotavirus-negative specimens. Over 73% of the NoV sequences belonged to GII/4 (Lordsdale cluster) and were detected in all months except March. We also detected GII/3 strains (Saitama U201 cluster), a naturally occurring recombinant NoV, between January 2000 and March 2000 but not after this period. Other NoV strains belonging to GI/4, GI/8, GII/1, and GII/7 were also detected but were infrequent. In addition, two almost identical NoV GII strains (strains 026 and 0703) collected six months apart were classified into a new genotype that includes the Mc37 strain, which was previously shown to be a recombinant NoV. During this one-year study, the NoV prevailed at the end of the rainy season and the beginning of the dry season. Further epidemiological studies may be necessary to determine whether the GII/4 strains continue to dominant in this region.

Adolescent↗
PubMed2004

DNA vaccine-encapsulated virus-like particles derived from an orally transmissible virus stimulate mucosal and systemic immune responses by oral administration.

Delivery of foreign genes to the digestive tract mucosa by oral administration of nonreplicating gene transfer vectors would be a very useful method for vaccination and gene therapy. However, there have been few reports on suitable vectors. In the present study, we found that plasmid DNA can be packaged in vitro into a virus-like particle (VLP) composed of open reading frame 2 of hepatitis E virus, which is an orally transmissible virus, and that these VLPs can deliver this foreign DNA to the intestinal mucosa in vivo. The delivery of plasmid DNA to the mucosa of the small intestine was confirmed by the results of immunohistochemical analyses using an expression plasmid encoding human immunodeficiency virus env (HIV env) gp120. After oral administration of VLPs loaded with HIV env cDNA, significant levels of specific IgG and IgA to HIV env in fecal extracts and sera were found. Moreover, mice used in this study exhibited cytotoxic T-lymphocyte responses specific to HIV env in the spleen, Payer's patches and mesenteric lymph nodes. These findings suggest that VLPs derived from orally transmissible viruses can be used as vectors for delivery of genes to mucosal tissue by oral administration for the purpose of DNA vaccination and gene therapy.

AIDS Vaccines↗
PubMed2004

Longevity-associated mitochondrial DNA 5178 A/C polymorphism and blood pressure in the Japanese population.

It has been reported that the mitochondrial DNA 5178 adenine/cytosine (mt5178 A/C) polymorphism, also called NADH dehydrogenase subunit 2-237 methionine/leucine (ND2-237 Met/Leu) polymorphism, may be associated with longevity in Japanese individuals, and that the mt5178A genotype may have an antiatherogenic influence. To determine whether mt5178 A/C polymorphism influences blood pressure, we genotyped 412 healthy Japanese individuals and performed a cross-sectional study investigating the relationship between genotype and blood pressure. In women with mt5178A, the mean diastolic blood pressure was higher than in those with mt5178C by 3.2 mmHg (P=0.040). In men, no statistically significant difference in systolic or diastolic blood pressure was observed between mt5178 A/C genotypes. However, a significant correlation between mt5178 A/C genotypes and the effects of habitual drinking on blood pressure was found. After adjustment for several factors, in men carrying mt5178C, both systolic and diastolic blood pressure were significantly higher in daily drinkers than in occasional (P=0.002 and 0.002, respectively) as well as nondrinkers (P<0.001 and 0.001, respectively), whereas in men carrying mt5178A, no significant differences in blood pressure were detected, irrespective of alcohol consumption. These results suggest that mt5178 A/C (=ND2-237 Met/Leu) polymorphism may influence both diastolic blood pressure in Japanese women and the blood-pressure-increasing effect of drinking in Japanese men.

Alcohol Drinking↗
PubMed2003

Discovery of temperature-dependent phenomena of muon-catalyzed fusion in solid deuterium and tritium mixtures.

A systematic experimental study on muon-catalyzed fusion was conducted using a series of solid deuterium and tritium mixtures. A variety of conditions were investigated, i.e., tritium concentrations from 20% to 70%, and temperatures from 5 to 16 K. With decreasing temperature, we observed an unexpected decrease in the muon cycling rate (lambda(c)) and an increase in the muon loss probability (W). The origins of these observed changes were interpreted by the temperature-dependence in the dt mu formation process for lambda(c) and that in the muon reactivation process after muon-to-alpha sticking for W.

Journal Article↗
PubMed2003

Diaphragm pacing with the spinal cord stimulator.

BACKGROUND: Diaphragm pacing with electrical stimulation of the phrenic nerve is an established treatment for central hypoventilation syndrome. The device, however, is not readily available, at least, in Japan. We applied the spinal cord stimulator for pain control to phrenic nerve stimulation. The purpose of this study is to evaluate the efficacy and feasibility of phrenic pacing with the compromise method. METHOD AND PATIENTS: We implanted a spinal cord stimulator in five patients with chronic central hypoventilation. The stimulation electrode was placed along the phrenic nerve in the neck, and the device was implanted in the anterior chest. We used the cyclic mode, and set the parameters at 1 second ramp up, 2 seconds on, 3 seconds off. The pulse width and the frequency were set at 150 microsec and 21 Hz respectively. The amplitude was adjusted to obtain sufficient tidal volume and to maintain PaCO2 at around 40 mmHg. FINDINGS: During the follow-up period from 3 to 34 months (mean 23), stable and sufficient ventilation were observed in all patients without complications. INTERPRETATION: Although longer follow-up is necessary, diaphragm pacing with the spinal cord stimulator is feasible for treatment of central hypoventilation syndrome.

Adult↗
PubMed2003

Inhibition of attachment of virions of Norwalk virus to mammalian cells by soluble histone molecules.

Viral infection is usually initiated by the binding of virus particles to specific receptor molecule(s) on the host cell surface. Blocking of this step prevents the following step, penetration into the cell. In the present study, we investigated the virus-cell interactions of virions of Norwalk virus (NV), a major etiological agent for viral diarrhea. We found that histone was an extremely strong NV-binding protein. Histone H1, a heterologous histone molecule, appeared to be able to interact not only with NV particles, but also with the cell surface. Histone H1 appeared capable of effectively preventing the attachment of NV to intestinal cells, but not of other viruses. No cytotoxic effects of histone were observed under the assay conditions. These results indicate that nonsecretory histone molecules may inhibit the attachment of viruses to cells like lactoferrins. Our results suggest that by searching virus-binding molecules, we might find antiviral agents, even for new viruses.

Animals↗
PubMed2002

Soy product intake and serum isoflavonoid and estradiol concentrations in relation to bone mineral density in postmenopausal Japanese women.

To evaluate soy intake and serum concentrations of estradiol and isoflavonoids and their relationship to bone mineral density (BMD) and serum bone-specific alkaline phosphatase (bone ALP) activity, we conducted a cross-sectional study of 87 postmenopausal Japanese women. Soy product and isoflavone intake from soy products and intake of nutrients were assessed with a semiquantitative food-frequency questionnaire. BMD (mg/cm2) was measured by single-energy X-ray absorptiometry at the site of the calcaneus. Serum estradiol (E2) and the sex hormone-binding globulin (SHBG) were measured by radioimmunoassay. Serum genistein and daidzein concentrations were measured by a high-performance liquid chromatography MS/MS method. A statistically significant correlation was observed between the ratio of E2 to SHBG and BMD (Spearman r=0.38, p=0.0003) after controlling for age, body mass index, smoking status, age at menarche, and intake of vegetable fat, vitamin C and salt. Soy product and isoflavone intake and serum isoflavones were not significantly correlated with BMD after controlling for the covariates. Serum ALP was not significantly correlated with soy product and isoflavone intake, the E2/SHBG ratio or serum isoflavones. The present study supports the association of BMD with serum estradiol; however, it does not support the association of BMD with soy or isoflavone intake or serum isoflavone levels.

Adult↗
PubMed2002

Pica in mice as a new model for the study of emesis.

In general, rats and mice have not been used in research on emesis because they do not vomit. However, emetogenic stimuli such as anticancer drugs, apomorphine, copper sulfate and rotation induced pica, a behavior characterized by eating nonfood substances such as kaolin, in rats. We also found that cisplatin induced pica in mice, but it was rather difficult to determine the exact kaolin consumption in this species. In this study, we prepared kaolin pellets mixed with carmine, a dye not absorbed in the gastrointestinal tract, and estimated kaolin consumption by determination of carmine excreted in feces. Cisplatin (5 mg/kg) caused a significant increase in kaolin consumption (saline: 0.15 +/- 0.08 g vs. cisplatin: 0.45 +/- 0.16 g) and pretreatment with the 5-HT3 receptor antagonist, ondansetron (2 mg/kg), suppressed the increased consumption (vehicle: 0.33 +/- 0.05 g vs. ondansetron: 0.13 +/- 0.04 g). These findings suggested that the exact kaolin consumption could be quantified by the determination of carmine in feces and that mice could be useful for studying emesis.

Animals↗
PubMed2001

Ferromagnetic exchange coupling of vanadium(IV) dpi spins across pyrimidine rings: dinuclear complexes of oxovanadium(IV) bis(1,1,1,5,5,5-hexafluoropentane-2,4-dionate) bridged by pyrimidine derivatives.

Dinuclear oxovanadium(IV) complexes bridged by pyrimidine derivatives, L[VO(hfac)(2)](2) [L = pyrimidine (PM), 4-methylpyrimidine (MPM), 4,6-dimethylpyrimidine, 4-aminopyrimidine, and quinazoline; hfac = 1,1,1,5,5,5-hexafluoropentane-2,4-dionate], were synthesized and characterized. All of them showed intramolecular ferromagnetic interaction, and the magnetic susceptibilities were analyzed on the basis of the singlet-triplet model, giving 2J/k(B) = 2.2-5.5 K. PM[VO(hfac)(2)](2) crystallized in a monoclinic space group C2/c with a = 34.092(2), b = 6.9783(4), and c = 16.4940(9) A, beta = 109.104(1) degrees, V = 3707.8(4) A(3), and Z = 4 for C(24)H(8)F(24)N(2)O(10)V(2), and MPM[VO(hfac)(2)](2) gave isomorphous crystals. A semiempirical calculation study based on the determined structure suggests the presence of dpi-ppi interaction between vanadium and pyrimidine nitrogen atoms. Ferromagnetic coupling is explained in terms of a spin-polarization mechanism across the pyrimidine bridge. The intermolecular ferromagnetic interaction of PM[VO(hfac)(2)](2) can be interpreted by the contact between the spin-polarized pyrimidine moiety and the oxovanadium oxygen atom in an adjacent molecule.

Journal Article↗