Search PubMed⌕ Search

Biomedical subjects

Keiko Tanaka

Publications and source records attributed to Keiko Tanaka.

At least 37 records · Page 2Linked to original sources
PubMed2005

Studies on absorption and hydrolysis of ethyl alpha-D-glucoside in rat intestine.

Ethyl alpha-D-glucoside (alpha-EG) is normally contained in Sake, which has been taken by Japanese people since ancient times. In this study, the intestinal absorption of alpha-EG was investigated using rat everted intestinal sac. Furthermore, the alpha-EG hydrolytic activity in rat intestine was compared with disaccharides hydrolytic activities, and the effects of alpha-EG on disaccharides hydrolysis were examined using crude enzyme preparation from rat intestinal acetone powder. Glucose liberated from alpha-EG was detected in a serosal solution of everted rat intestinal sac, but it was only less than 4% of absorbed intact alpha-EG. alpha-EG absorption into small intestinal tissue was reduced by elimination of sodium ion from the mucosal solution or under the presence of phlorizin. The hydrolytic activity for alpha-EG was detected in crude enzyme preparation from rat intestinal acetone powder, but it showed a low value as compared to those for disaccharides. alpha-EG showed mixed type inhibition for maltose and sucrose hydrolysis, but inhibitory concentrations of alpha-EG required for 50% inhibition for the maltose and sucrose hydrolysis were higher than those of arabinose and acarbose. In conclusion, a small amount of alpha-EG was hydrolyzed and most of it was absorbed via SGLT1 as an intact form in the rat small intestine, and the inhibitory effect of alpha-EG on disaccharides hydrolysis was weak.

Animals↗
PubMed2005

Functional SNPs in the distal promoter of the ST2 gene are associated with atopic dermatitis.

Atopic dermatitis (AD) is a common inflammatory skin disease associated with the local infiltration of T helper type 2 (Th2) cells. The ST2 gene encodes both membrane-bound ST2L and soluble ST2 (sST2) proteins by alternative splicing. The orphan receptor ST2L is functionally indispensable for Th2 cells. We found a significant genetic association between AD and the -26999G/A single nucleotide polymorphism (SNP) (chi2-test, raw P-value=0.000007, odds ratio 1.86) in the distal promoter region of the ST2 gene (chromosome 2q12) in a study of 452 AD patients and 636 healthy controls. The -26999A allele common among AD patients positively regulates the transcriptional activity of the ST2 gene. In addition, having at least one -26999A allele correlated with high sST2 concentrations and high total IgE levels in the sera from AD patients. Thus, the -26999A allele is correlated with an increased risk for AD. We also found that the -26999G/A SNP predominantly affected the transcriptional activity of hematopoietic cells. Immunohistochemical staining of a skin biopsy specimen from an AD patient in the acute stage showed ST2 staining in the keratinocytes as well as in the infiltrating cells in the dermal layer. Our data show that functional SNPs in the ST2 distal promoter region regulate ST2 expression which induces preferential activation of the Th2 response. Our findings will contribute to the evaluation of one of the genetic risk factors for AD.

Alleles↗
PubMed2005

Inhibition of dentine demineralization by zinc oxide: in vitro and in situ studies.

OBJECTIVE: The objective of this study was to evaluate the inhibitory effect of zinc oxide on dentine demineralization in vitro and in situ. METHODS: In the in vitro study, dentine specimens treated with a zinc oxide suspension were demineralized in a pH 5 solution. In the in situ study, subjects wore dentine specimens on their teeth and instructed to rinse with zinc-containing toothpaste slurry three times a day for 14 days. The design of study was a crossover one. RESULTS: Microradiography employed in the in vitro study revealed the dentine surfaces treated with distilled water had a lower mineral content than those treated by zinc. Toothpaste with zinc had a statistically significant, 49% greater inhibitory efficacy on dentine demineralization over the control. In the in situ study, zinc-containing toothpaste was also confirmed to have an inhibitory effect on dentine demineralization when compared to the zinc-free toothpaste. These in vitro and in situ studies revealed that zinc oxide can have a significant effect on the inhibition of dentine demineralization, even when the zinc oxide is blended into toothpaste. SIGNIFICANCE: This suggests that zinc oxide may be effective in the prevention of root caries.

Adult↗
PubMed2005

Human papillomavirus 16 minor capsid protein L2 helps capsomeres assemble independently of intercapsomeric disulfide bonding.

The human papillomavirus (HPV) capsomeres (pentamers of major capsid protein L1), which constitute along with L2 the virion capsid, can assemble themselves alone into the L1-capsid particles in vivo and in vitro, depending on intercapsomeric disulfide bonds. To study a possible role of L2 in capsid assembly, we examined the interaction between HPV16 L2 and capsomeres under the conditions that inhibit the formation of disulfide bonds in vitro and in vivo. The purified L2 bound to free capsomeres prepared by disassembling L1-capsids but not to the L1-capsids in vitro. And the L2 was found to help capsomeres assemble into smaller capsid-like particles independently of intercapsomeric disulfide bonding. Similar particles were obtained from the Sf9 cells co-infected with baculoviruses expressing L2 and an L1 mutant that lacks a C-terminal cysteine (C428S) and can form capsomeres but no capsids when expressed alone. These findings suggest that L2, which is known to bind both viral DNA and L1, may contribute to the formation of the virion by linking viral DNA and capsomeres and by helping capsomeres assemble before the virion capsid structure is completed by dintercapsomeric disulfide bonding.

Animals↗
PubMed2005

Active and passive smoking and tooth loss in Japanese women: baseline data from the osaka maternal and child health study.

PURPOSE: Many studies have shown a positive association between cigarette smoking and oral diseases. Few studies, however, have focused on the relationship between passive smoking exposure and oral health in adults. We investigated the association of active and passive smoking exposure with tooth loss in Japan. METHODS: Study subjects were 1002 pregnant women. Tooth loss was defined as previous extraction of one or more teeth. Adjustment was made for age, gestation, parity, family income, education, and body mass index. RESULTS: Of the 1002 subjects, 256 women had lost one or more teeth. Current light smoking was independently related to an increased prevalence of tooth loss, showing a significant exposure-related association with smoking status. A significant positive association of 8 or more pack-years of smoking with the prevalence of tooth loss was observed. Also, a significant positive relationship was found between current heavy passive smoking at home and tooth loss, but not with pack-years of passive smoking at home. No measurable association between passive smoking exposure at work and tooth loss was indicated. CONCLUSIONS: The present findings suggest that passive as well as active smoking may be associated with an increased prevalence of tooth loss in Japanese young adult women.

Adult↗
PubMed2005

Paraneoplastic neurologic syndrome and autoimmune Addison disease in a patient with thymoma.

A 48-year-old man with autoimmune Addison disease developed the following paraneoplastic neurologic syndromes (PNNS): limbic encephalitis, opsoclonus/myoclonus, and sensorimotor and autonomic neuropathies. An anterior mediastinal mass detected on a chest computed tomographic scan was found on resection to be a noninvasive lymphocytic thymoma. The PNNS went into remission 1 year after the thymectomy. This is the first case of thymoma associated with autoimmune Addison disease and PNNS to be described in the literature.

Addison Disease↗
PubMed2005

Molecular determinants for subcellular localization of hepatitis C virus core protein.

Hepatitis C virus (HCV) core protein is a putative nucleocapsid protein with a number of regulatory functions. In tissue culture cells, HCV core protein is mainly located at the endoplasmic reticulum as well as mitochondria and lipid droplets within the cytoplasm. However, it is also detected in the nucleus in some cells. To elucidate the mechanisms by which cellular trafficking of the protein is controlled, we performed subcellular fractionation experiments and used confocal microscopy to examine the distribution of heterologously expressed fusion proteins involving various deletions and point mutations of the HCV core combined with green fluorescent proteins. We demonstrated that a region spanning amino acids 112 to 152 can mediate association of the core protein not only with the ER but also with the mitochondrial outer membrane. This region contains an 18-amino-acid motif which is predicted to form an amphipathic alpha-helix structure. With regard to the nuclear targeting of the core protein, we identified a novel bipartite nuclear localization signal, which requires two out of three basic-residue clusters for efficient nuclear translocation, possibly by occupying binding sites on importin-alpha. Differences in the cellular trafficking of HCV core protein, achieved and maintained by multiple targeting functions as mentioned above, may in part regulate the diverse range of biological roles of the core protein.

Amino Acid Sequence↗
PubMed2005

Association of melanin pigmentation in the gingiva of children with parents who smoke.

OBJECTIVE: The association between gingival pigmentation and active smoking has been established. This investigation is the first to address the relationship between gingival pigmentation in children and passive smoking. METHODS: A case-control study was performed involving 59 nonsmoking children who were selected from patient records of a dental clinic in a rural town in Japan. The number of subjects was based on a power calculation. Two calibrated examiners independently observed labial gingiva via oral photographs. RESULTS: An interview determined that 61% of children had at least 1 smoking parent. Gingival pigmentation was observed in 71% to 78% of children. Interexaminer agreement was satisfactory (kappa = 0.73). Percentage of smoking parents was higher in children with gingival pigmentation (70-71%) than in those who lacked pigmentation (35%). Odds ratios of parental smoking adjusted by age and gender were 5.6 (95% confidence interval: 1.5-20.0) and 5.4 (1.4-21.2) for the 2 examiners. CONCLUSION: These findings suggest that excessive pigmentation in the gingiva of children is associated with passive smoking. The visible pigmentation effect in gingiva of children could be useful in terms of parental education.

Adolescent↗
PubMed2005

[Evaluation of two patients with SCA2 with frontal lobe dysfunction using brain SPECT with three-dimensional stereotactic surface projections (3D-SSP)].

We evaluated the cognitive impairment of two patients with genetically confirmed spinocerebellar ataxia type 2 (SCA2). Neurological examination revealed ignorance of his illness and Gegenhalten phenomenon in patient 1, and emotional incontinence in patient 2. Although their mental status evaluated by HDS-R or Mini-Mental State Examination (MMSE) was almost normal, the results of WAIS-R and Wisconsin Card Sorting Test (WCST) revealed the existence of intellectual decline and executive dysfunction. 3D-SSP SPECT demonstrated distinct hypoperfusion in bilateral frontal lobes, whereas brain MRI revealed no apparent cerebral atrophy in both patients. These results raise the possibility that frontal lobe dysfunction was observed in the early stages of SCA2, and that 3D-SSP SPECT is useful for evaluating the involvement of frontal lobe dysfunction in SCA2.

Adult↗
PubMed2005

[A pedigree of Charcot-Marie-Tooth disease type 4F (Periaxin mutation)].

We report a 51-year-old man genetically diagnosed as Charcot-Marie-Tooth disease type 4F. The patient was the first child of healthy, consanguineous parents. He had two sisters and one of them showed similar but milder symptoms. He had gait disturbance since childhood. Then he noticed muscle weakness of his hands at the age of early forties, and more difficulties in gait at the age of late forties. On examination at age 51, he showed absence of all deep tendon reflexes, weakness of the hand and distal leg muscles, pes cavus and decreased sensitivity to touch and vibration in the lower extremities. Electrophysiological studies of the median nerve showed delayed motor nerve conduction velocity and undetectable sensory nerve action potentials. The histology of his sural nerve revealed moderate loss of large myelinated fibers and the diameters of residual fibers shifted to small shown as size-frequency histogram. Many fibers are thinly myelinated and some of the Schwann cells looked as wrapping around the myelinate fibers with their processes. On gene analyses, we identified an Arg 1070 Stop homozygous mutation in the Periaxin, known to be a causative gene for CMT type 4F. Based on these observations, we emphasized that broad genetic analyses are necessary for diagnosis of CMT disease, including so far unidentified mutations among the Japanese populations.

Charcot-Marie-Tooth Disease↗
PubMed2005

[Heat treatment for the control of Bacillus cereus spores in foods].

The effect of heat treatments on food products related to soybean curd contaminated with Bacillus cereus spores was investigated for the purpose of preventing food-poisoning outbreaks by B. cereus. In the case of B. cereus strains isolated from foods, heating foods inoculated with the spores for 20 min at 70 degrees C, 5 min at 75 degrees C, 2 min at 100 degrees C, or 10 sec with a microwave oven plus reheating after standing for 2 hr at 25 degrees C reduced the number of surviving cells within the foods to less than one-hundredth. In the case of a heat-resistant strain isolated from a food poisoning outbreak, heating for 20 min at 70 degrees C plus reheating after standing for 1.5-2 hr at 35 degrees C, heating for 10 min at 75 degrees C plus reheating after standing for 1.5-2 hr at 35 degrees C, or heating for 2 min at 100 degrees C plus reheating after standing for 4 hr at 25 degrees C was effective. There was not much difference between the flavor components in foods with and without heat treatment at 70 degrees C, as analyzed by gas chromatography-mass spectrometry. These results indicate that these heat treatments are available to control B. cereus spores, without affecting the sensory quality of the foods.

Bacillus cereus↗
PubMed2005

[Relationship between life satisfaction and lifestyle in residents of Kyoto].

OBJECTIVE: The purpose of this study was to assess relationships between life satisfaction and lifestyle in residents of the city of Kyoto, Japan, by addressing their subjective evaluation of their own health status. METHODS: The subjects comprised 4746 men and women (15-97 years old) who had completed a questionnaire on life style in the 1998 Kyoto Citizen's Health and Nutrition Study. Stratified by their responses to subjective health, the relationship between life-satisfaction and lifestyle was evaluated by odds ratios and chi-square tests of the subjects classified by age and gender. RESULTS: The proportion of respondents who felt their subjective health was good decreased with age, while the proportion of respondents who considered their life satisfaction good increased with age. Whether the residents had good or poor subjective health, the proportion of respondents who had a healthy lifestyle, as exemplified by having breakfast everyday, having dinner with their family regularly and having a good intake of greeny-ellow vegetables increased with age in both men and women. This healthy lifestyle was also positively associated with good life satisfaction. CONCLUSION: Whether the residents had good or poor subjective health, these results suggest that thos with a healthy lifestyle feel good life satisfaction.

Adolescent↗
PubMed2005

[A late-onset case of oculopharyngeal muscular dystrophy carrying a (GCG)8 repeat expansion in the PAPBN1 gene].

We report a sporadic case of a female patient with oculopharyngeal muscular dystrophy (OPMD). Her father died at age 86 and mother at age 74. There was no familial occurrence of the disease. The patient initially developed a nasal voice at age 66. Neurological examinations on admission at age 72 revealed bilateral ptosis, a limitation of ocular movement without diplopia, dysphagia, and proximal muscle weakness. Serum creatine kinase level was slightly increased. Biopsied muscle specimens showed variation in fiber size as well as the occasional presence of rimmed vacuoles. On the basis of these clinical and laboratory findings, we suspected a diagnosis of OPMD, although a family history was absent. To confirm the diagnosis of OPMD, we performed a gene analysis for poly A binding protein, nuclear 1 (PABPN1; PABP2), which revealed a mild expansion of GCG repeat (8 repeats) as a heterozygous state. Clinical features of the patient were consistent with those in a previous literature reporting that patients carrying (GCG)8 repeat as a heterozygous state show a relatively late onset and a mild phenotype. The case of this patient emphasizes the importance of the PABPN1 gene analysis for patients showing muscular weakness involving oculopharyngeal and proximal limb muscles even when a familial occurrence of the disease is not apparent.

Aged↗
PubMed2004

Central nervous system immunity associated with clinical outcome in acute encephalitis.

To search for useful laboratory measures of central nervous system (CNS) immunity that may provide an accurate prognosis or clues regarding treatment choice, cerebrospinal fluid (CSF) samples were obtained from 14 consecutive patients with acute encephalitis during acute as well as convalescent or chronic stages, and then examined for surface antigen expressions by lymphocytes and the presence of antineuronal tissue antibodies as well as the levels of IgG-related parameters and proinflammatory cytokines, including IL-2, IL-6, IFN-gamma, and tumor necrosis factor-alpha (TNF-alpha). Seven patients with aseptic viral meningitis served as nonencephalitic controls. Eight of the 14 acute encephalitis patients recovered fully, and reductions in the percentages of CD4(+)CD29(+) helper inducer T cells and IL-2 receptor-positive CD4(+) cells were associated with early recovery and favorable outcome, respectively, whereas a low percentage of CD4(+)CD26(+) memory T cells during an acute stage was associated with an unfavorable outcome following adjunctive intravenous corticosteroid treatment. Further, three of the four encephalitis patients who exhibited autoantibodies had a poor prognosis. These findings suggest that CNS immunity status has an effect on prognosis, while flow cytometric analyses of CSF CD4(+) helper T cell subsets may serve as effective means of assessment.

Adolescent↗
PubMed2004

Churg-Strauss syndrome and the leukotriene receptor antagonist pranlukast.

The authors studied eight cases of Churg-Strauss syndrome (CSS) associated with the use of pranlukast, a common cysteinyl leukotriene receptor antagonist (LTRA) in Japan. The patients who received pranlukast showed significantly increased peripheral blood eosinophil count, neurological disability scores, and poor responses to corticosteroid in comparison with those patients not receiving pranlukast. We suggest that preceding administration of pranlukast aggravates clinical presentations of CSS.

Anti-Asthmatic Agents↗
PubMed2004

Effects of antineuronal antibodies from patients with paraneoplastic neurological syndrome on primary-cultured neurons.

Some patients with paraneoplastic neurological syndrome (PNS) produce autoantibodies against tumor and neuronal tissues of symptom-relevant areas. These characteristic antibodies are detected at early stages of the neurological disorder and are reliable markers for the diagnosis of PNS and underlying cancers. These antibodies are thought to be related directly to neuronal damage. However, the passive transfer of antibodies to rodents has been succeeded only in those in which the target antigens were expressed on the cell surface, like Lambert-Eaton myasthenic syndrome. The serum IgGs from patients with PNS and anti-Yo or anti-Hu antibody were not shown to induce the disease by passive transfer or active immunization with these antigen proteins to date. Instead, cytotoxic T lymphocytes (CTLs) against these antigen peptides-presenting targets could be induced in the peripheral blood of PNS patients. However, there is no direct proof of CTLs killing neurons. In this study, we examined the effects of the anti-Yo or anti-Hu antibody on mouse-brain-derived neurons in a primary culture system and found that these antibodies did not kill neurons, but induced the expression of cell adhesion molecules and accelerated neuronal differentiation. These effects of serum IgG fractions containing the anti-Yo or the anti-Hu antibody on the cultured neurons were the same, suggesting that their effects were not through the binding of the antibody to specific antigens, but to some other factors contained in IgG fractions.

Animals↗