Biomedical subjects

T Iwata

Publications and source records attributed to T Iwata.

At least 37 records · Page 2Linked to original sources

PubMed2003

Papanicolaou tests and molecular analyses using new fluid-based specimen collection technology in 3000 Japanese women.

A fluid-based Papanicolaou test has been established to improve sample collection and preparation. This study was the first large-scale investigation in Japan to examine the feasibility of using fluid-based Papanicolaou specimens to detect human papillomavirus (HPV) using Hybrid Capture II and polymerase chain reaction (PCR). Three thousand patients who visited Keio University Hospital between October 2000 and February 2001 were enrolled in the study. The results of the fluid-based Papanicolaou tests corresponded well with those of conventional Papanicolaou smears (96.8% concordance). The sensitivities of cervical neoplasia detection using the fluid-based Papanicolaou test (73.9%) and Hybrid Capture II (76.3%, P=0.55) were not significantly different. Among the cervical intraepithelial neoplasia 3 and squamous cell carcinoma specimens, HPV 16 and HPV 52 were predominantly detected using the PCR method. Although some DNA samples extracted from the fluid-based specimens were degradaded, PCR and direct sequencing could be performed without difficulty even after 1 year of specimen storage. We conclude that fluid-based Papanicolaou specimens can be applied to investigate HPV infection.

DNA, Viral↗

PubMed2003

Comparison of the effects of sevoflurane and propofol on cooling and rewarming during deliberate mild hypothermia for neurosurgery.

BACKGROUND: Because the time available for cooling and rewarming during deliberate mild hypothermia is limited, studies of the rate of the cooling and rewarming are useful. The decrease in core hypothermia caused by heat redistribution depends on the anaesthetic agent used. We therefore investigated possible differences between sevoflurane and propofol on the decrease and recovery of core temperature during deliberate mild hypothermia for neurosurgery. METHODS: After institutional approval and informed consent, 26 patients were assigned randomly to maintenance of anaesthesia with propofol or sevoflurane. Patients in the propofol group (n=13) received propofol induction followed by a continuous infusion of propofol 3-5 mg kg(-1) h(-1). Patients in the sevoflurane group (n=13) received propofol induction followed by sevoflurane 1-2%. Nitrous oxide and fentanyl were also used for anaesthetic maintenance. After induction of anaesthesia, patients were cooled and tympanic membrane temperature was maintained at 34.5 degrees C. After surgery, patients were actively rewarmed. RESULTS: There was no difference in the rate of decrease and recovery of core temperature between the groups. There was also no difference in skin surface temperature gradient (forearm to fingertip), heart rate and mean arterial blood pressure between the groups. CONCLUSIONS: Sevoflurane-based anaesthesia did not affect cooling and rewarming for deliberate mild hypothermia compared with propofol-based anaesthesia.

Adult↗

PubMed2002

Helicity amplitudes A1/2 and A3/2 for the D13(1520) resonance obtained from the gamma-->p-->-->ppi(0) Reaction.

The helicity dependence of the gamma-->p-->-->ppi(0) reaction has been measured for the first time in the photon-energy range from 550 to 790 MeV. The experiment, performed at the Mainz microtron MAMI, used a 4pi-detector system, a circularly polarized, tagged photon beam, and a longitudinally polarized frozen-spin target. These data are predominantly sensitive to the D13(1520) resonance and are used to determine its helicity amplitudes.

Journal Article↗

PubMed2002

Polymorphisms of human CD19 gene: possible association with susceptibility to systemic lupus erythematosus in Japanese.

CD19 regulates the signaling for B lymphocyte development, activation and proliferation. In mice, CD19 deficiency and overexpression were shown to result in hypogammaglobulinemia and autoantibody production, respectively. In the present study, we screened for the polymorphisms of CD19, and examined the detected polymorphisms for the association with rheumatoid arthritis (RA), Crohn's disease and systemic lupus erythematosus (SLE). Two SNPs, c.705G>T (P235P and IVS14-30C>T, were decreased (P = 0.0096 and P = 0.028, respectively), in SLE. A GT repeat polymorphism, c.*132(GT)(12-18), was detected within the 3'-untranslated region, and individuals with > or =15 times repeat was significantly increased in the independent two groups of Japanese SLE patients (P = 0.011 and P = 0.035, respectively); the overall difference between total SLE and controls was striking (P = 0.0061). No association was observed for RA and Crohn's disease. In addition, no variations other than the common polymorphisms were detected in four patients with common variable immunodeficiency, the phenotype of which resembles CD19 deficient mice. In Caucasian SLE families, this GT repeat polymorphism was rare. CD19 mRNA level in the isolated peripheral blood B lymphocytes was lower in individuals possessing (GT)(15-18) alleles compared with those without these alleles, both in controls and in SLE patients; however, the difference did not reach statistical significance. These results suggested that either the slight reduction in the CD19 mRNA level associated with the elongation of GT repeat, or an allele of another locus in linkage disequilibrium with CD19 (GT)(15-18), may be associated with susceptibility to SLE in Japanese.

3' Untranslated Regions↗

PubMed2002

Association of polymorphisms of the renin-angiotensin system and bradykinin B2 receptor with ACE-inhibitor-related cough.

The use of angiotensin-converting enzyme (ACE) inhibitors to treat hypertension has recently increased. However, their use is associated with a persistent dry cough in a significant percentage of such patients. The present study was designed to assess the contribution of polymorphisms as a genetic marker of ACE-inhibitor-related cough in a Japanese hypertensive population. Genotyping was carried out in 190 patients, 70 with cough and 120 without cough, who had been treated with ACE inhibitors. Polymorphisms of ACE insertion/deletion (I/D), angiotensin II type 1 receptor (1166A/C), type 2 receptor (3123C/A), and bradykinin B2 receptor (-58T/C, exon 1, I/D), were analyzed in these subjects. The TT genotype and T allele of bradykinin B2 receptor (-58T/C) were identified at a significantly higher frequency in the cough (+) patients than in the cough (-) patients. This difference was even more pronounced in women. However, there was no significant relationship between polymorphisms of ACE, angiotensin II receptors, or bradykinin B2 receptor exon 1, and occurrence of ACE-inhibitor-related cough. The transcriptional activity of the bradykinin B2 receptor promoter is involved in the occurrence of cough, and this new marker may provide a valuable tool to detect patients at risk of developing this side effect of ACE inhibitors. In conclusion, Susceptibility to develop cough is associated with a genetic variant of the bradykinin B2 receptor promoter; thus, it may be possible to identify those patients who will develop this adverse reaction to ACE inhibitors in advance.

Adult↗

PubMed2002

Influence of dietary conjugated linoleic acid isomers on early inflammatory responses in male broiler chickens.

1. The influence of dietary conjugated linoleic acid isomer (CLA, 0 and 10 g/kg) on the metabolic and physiological responses to immune stimulation induced by a single injection of Salmonella enteritidis lipopolysaccharide (LPS) or repeated injections of LPS and Sephadex G-50 was determined in male broiler chicks. 2. In experiment 1, 10-d-old chicks were fed on experimental diets for 14 d and half of the birds fed on each diet were injected intraperitoneally with LPS (1.5 mg/kg body weight). In experiment 2,7-d-old chicks were fed on experimental diets for 18 d. Immune stimulation was started at 19 d old and continued for 5 d. Half of the birds fed on each diet were injected intraperitoneally with 0.25 mg/kg body weight of LPS at 19, 21 and 23 d of age, and with 250 mg/kg body weight of Sephadex at 20 and 22 d of age to stimulate the immune system. 3. In experiment 1, giving CLA prevented an increase in blood heterophil to lymphocyte ratio 7 h after a single injection of LPS, and increases in plasma ceruloplasmin and alpha 1 acid glycoprotein (AGP) 24 h after the injection, but not 7 h after the injection. CLA also prevented a decrease in food intake for 24 h after LPS injection. 4. In experiment 2, the CLA diet partially prevented reductions in body weight gain and weight gain to feed intake ratio caused by repeated injections of LPS and Sephadex. Feeding CLA prevented increases in plasma ceruloplasmin and AGP at 24 d of age caused by repeated injections of LPS and Sephadex, but not at 20 d of age. 5. These results suggest that feeding CLA alleviates some undesirable metabolic and physiological changes induced by immunological stimulation in male broiler chicks.

Animals↗

PubMed2002

Noggin blocks osteoinductive activity of porcine enamel extracts.

Enamel extracts induce biomineralization such as osteogenesis and cementogenesis, but the molecular component responsible for this activity remains uncertain. We fractionated enamel extracts from developing pig teeth and isolated the osteoinductive fraction. Proteins from pig enamel scrapings were extracted under alkaline conditions (pH 10.8) and fractionated with the use of a Sephadex G-100 (size exclusion) column. The ability of each fraction to enhance alkaline phosphatase (ALP) activity was assayed in ST2 cells, a mouse bone marrow stromal cell line. The osteoinductive fraction of enamel extracts (OFE) was found in fractions 44 and 45, which induced ST2 cells to express the phenotype of bone-forming osteoblasts, and to form mineralized nodules. Furthermore, the ALP activity of ST2 cells exposed to OFE was reduced by noggin, an antagonist of BMPs, and OFE reacted with BMP-2/4 antibody in dot-blot analysis. These results indicate that OFE contains BMPs that contribute to the induction of biomineralization.

Alkaline Phosphatase↗

PubMed2002

[Nodular pulmonary amyloidosis with bullae; report of a case].

A 53-year-old male was admitted to the hospital because of progressive paralysis of inferior limb. Chest X-ray film and chest computed tomography (CT) on admission showed a small nodule with bullae in the right lower lung field. After CT-guided marking, partial lung resection including the nodule was performed. The cut surface of the resected specimen showed a tumor (10 mm in diameter) in a bullae measuring 14 mm in diameter. The tumor was diagnosed as amyloidosis. Fourty-six cases of primary localized pulmonary amyloidosis were reported in Japan. However, primary localized pulmonary amyloidosis with bullae is extremely rare, only 3 cases have been reported.

Amyloidosis↗

PubMed2001

Immunohistochemical studies on the distribution of nerve fibers in the human prostate with special reference to the anterior fibromuscular stroma.

BACKGROUND: Although the anterior fibromuscular stroma (AFMS) comprises up to one third of the total bulk of the prostate, its physiological function remains unknown. We recently reported the possible contribution of the AFMS to micturition. The aim of this study is to reveal the differences in the distribution of innervation between the AFMS and the other regions of the prostate. METHODS: We performed immunohistochemical stainings using antibodies such as protein gene product (PGP) 9.5, tyrosine hydroxylase(TH), neuropeptide Y (NPY), and vasoactive intestinal peptide (VIP). Morphometric analysis was made to examine the density of peripheral nerve fibers containing PGP 9.5, TH, NPY, and VIP by using a computer-assisted imaging system. RESULTS: The number of PGP 9.5-immunoreactive (IR) nerve fibers and the smooth muscle in the AFMS decreased from the base to the apex of the prostate. TH-IR nerve fibers were more abundant in the AFMS than in the transition zone. NPY- and VIP-IR nerve fibers were less numerous in the AFMS than in the peripheral zone. CONCLUSIONS: This study is the first to demonstrate that the AFMS has peculiar neuronal innervation. We observed significantly different innervation in the AFMS compared with the other regions of the prostate.

Aged↗

PubMed2001

Site-dependent modulating effects of conjugated fatty acids from safflower oil in a rat two-stage carcinogenesis model in female Sprague-Dawley rats.

Modifying effects of dietary administration of conjugated fatty acids from safflower oil (CFA-S), rich in conjugated linoleic acid, on major organs were examined in the post-initiation stage of a two-stage carcinogenesis model in female rats. Groups of 21 or 22 F344 female rats were treated sequentially with 2,2'-dihydroxy-di-n-propylnitosamine (intragastrically, i.g.), 7,12-dimethylbenz[a]anthracene (i.g.), 1,2-dimethylhydrazine (subcutaneously) and N-butyl-N-(4-hydroxybutyl)nitrosamine (in drinking water) during the first 3 weeks for initiation, and then administered diet containing 1 or 0.1% CFA-S for 33 weeks. Further groups of animals were treated with carcinogens or 1% CFA-S alone, or maintained as non-treated controls. All surviving animals were killed at week 36, and major organs were examined histopathologically for development of pre-neoplastic and neoplastic lesions. The 1 and 0.1% CFA-S treatment significantly decreased the incidence and multiplicity of mammary carcinomas, though a clear dose response was not observed. In the urinary bladder, the incidence of papillary or nodular hyperplasia but not tumors was significantly increased in the 1% CFA-S-treated group. The results indicate that low dose CFA-S may find application as a potent chemopreventor of mammary carcinogenesis.

1,2-Dimethylhydrazine↗

PubMed2001

Highly activated Fgfr3 with the K644M mutation causes prolonged survival in severe dwarf mice.

Several gain-of-function mutations in a receptor tyrosine kinase, fibroblast growth factor receptor 3 (FGFR3), cause dwarfism in humans. Two particularly severe dwarfisms, thanatophoric dysplasia type II (TDII) and severe achondroplasia with developmental delay and acanthosis nigricans (SADDAN), are associated with glutamic acid (E) and methionine (M) substitutions at the K650 residue in the kinase domain. TDII is lethal at birth, whereas most of the SADDAN patients survive the perinatal period. However, FGFR3 with the SADDAN mutation is more activated than FGFR3 with the TDII mutation in vitro. To find out whether the K650M mutation also causes the SADDAN phenotype, we introduced the corresponding point mutation (K644M) into the mouse Fgfr3 gene. Heterozygous mutant mice show a phenotype similar to human SADDAN, e.g. the majority of the SADDAN mice survive the perinatal period. This suggests that the survival of SADDAN patients is indeed attributed to the K650M mutation in FGFR3. The long bone abnormalities in SADDAN mice are milder than the TDII model. In addition, overgrowth of the cartilaginous tissues is observed in the rib cartilage, trachea and nasal septum. The FGF ligand at the low concentration differentially activates Map kinase in primary chondrocyte cultures from wild-type and SADDAN mice. Comparisons of the molecular bases of the phenotypic differences in SADDAN and TDII mice may increase our understanding of the factors that influence the severity in these two related skeletal dysplasias.

Acanthosis Nigricans↗

PubMed2001

Comparison of intracytoplasmic sperm injection for inbred and hybrid mice.

We compared the results of intracytoplasmic sperm injection (ICSI) that leads to full term development of hybrid (B6C3F1 and B6D2F1) and inbred (C57BL/6) mouse embryos. Although fertilization and pre-implantation development of C57BL/6 eggs were similar to those of F1 hybrid eggs, post-implantation development of the embryos from C57BL/6 females was significantly poorer than those of the eggs from hybrid females. Reciprocal crosses of C57BL/6 and B6C3F1 gametes revealed that the low rate of post-implantation development of C57BL/6 embryos was due to oocyte factor(s), rather than the sperm factor.

Animals↗

PubMed2001

Molecular cloning of newt prolactin (PRL) cDNA: effect of temperature on PRL mRNA expression.

A partial prolactin (PRL) cDNA was specifically PCR amplified from a cDNA library constructed from pituitary mRNAs of the newt (Cynops pyrrhogaster) and cloned into plasmid vectors. One clone thus obtained contained a 739-bp insert encoding the C-terminal amino acid sequence of the mature hormone molecule. Using this clone as a probe, the full-length newt PRL cDNA was screened from the cDNA library. The PRL cDNA clone thus obtained consisted of 1024 bp encoding the entire sequence of the mature PRL molecule in addition to its signal peptide. The amino acid sequence of newt PRL deduced from its nucleotide sequence showed higher homologies with those PRL sequences of tetrapod animals than with those of teleosts. Northern blot analysis revealed the newt PRL mRNA size to be approximately 1 kb. In situ hybridization using the newt PRL cDNA as a probe revealed that the pituitary region expressing PRL mRNA corresponded to that immunoreactive with antiserum against PRL. PRL mRNA levels in the pituitary of newts subjected to room and low temperatures were determined by Northern analysis employing the PRL cDNA as a probe. PRL mRNA levels were significantly higher in the pituitaries of newts subjected to 10 degrees than in those of newts kept at 23 degrees. Likewise, immunoassayable plasma PRL levels were higher in animals subjected to 10 degrees than in those kept at 23 degrees.

Amino Acid Sequence↗

PubMed2001

Possible use of ultrasound estimated bladder weight in evaluating vesicoureteral reflux in children.

The present study was designed to reveal the possible use of ultrasound estimated bladder weight (UEBW) in evaluating vesicoureteral reflux (VUR) in children in terms of possible implication of bladder hypertrophy in VUR. In 27 children with VUR, UEBW was measured by transabdominal ultrasound. The UEBW in an individual patient was evaluated quantitatively using the percent deviation from age matched UEBW. There was a significant difference noted in the percent deviation from age-matched UEBW between patients (n = 17) with primary VUR and those (n = 10) with secondary VUR (p <.05). When analyzed together in 27 patients, a significant positive correlation (p <.05) was recognized between the percent deviation from age-matched UEBW and VUR grade. This was also the case in ten patients with secondary VUR (p <.01), but not for 17 patients with primary VUR. The measurement of UEBW might be of clinical use in evaluating the pathogenesis as well as the severity of VUR in children.

Adolescent↗

PubMed2001

Characterization of 13 kDa granule-associated protein in Aeromonas caviae and biosynthesis of polyhydroxyalkanoates with altered molar composition by recombinant bacteria.

Analysis of native poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) [P(3HB-co-3HHx)] inclusions from Aeromonas caviae FA440 revealed that ORF1 (a 348-bp gene located immediately upstream of phaC(Ac)) encodes a 13-kDa granule-associated protein, which was referred to as phaP(Ac). Several recombinant strains of A. caviae were constructed and conducted to analyze their PHA-producing abilities. A transconjugant of FA440 harboring additional copies of phaPCJ(Ac) genes accumulated P(3HB-co-3HHx) copolyesters with much higher 3HHx composition (46-63 mol %) than wild-type strain from alkanoates or olive oil. Deletion analysis revealed that overexpression of phaJ(Ac) encoding monomer-supplying (R)-hydratase was not a reason for the compositional change in the recombinant strains. PHA synthase activity in PHA inclusion fraction from the transconjugant composed of 60 mol % of 3HHx was 10-fold higher than that from the strain FA440 with 13 mol % of 3HHx, suggesting an importance of the level of PHA synthase activity for controlling the PHA composition in vivo.

Acyltransferases↗

PubMed2001

In situ observation of crystal growth for poly[(S)-lactide] by temperature-controlled atomic force microscopy.

The crystallization behavior and crystalline morphologies of poly[(S)-lactide] (P[(S)-LA]) in thin films crystallized isothermally at over 160 degrees C were characterized by transmission electron microscopy and atomic force microscopy (AFM). The dendritic crystal and hexagonal crystal were formed in thin film with thicknesses below 30 nm or over 50 nm, respectively. The crystal structures of dendritic and hexagonal crystals were identical, suggesting that the crystalline morphology of P[(S)-LA] is strongly dependent upon the film thickness. In situ observation of the crystal growth in the P[(S)-LA] thin film at 165 degrees C from the melt was carried out by using temperature-controlled AFM equipped with a heating stage. The initial stage of crystallization and development of lamellae were successfully observed during isothermal crystallization at 165 degrees C. The first forming crystal showed the edge-on orientation, and grew to S-shaped edge-on lamellae. Dendritic flat-on crystals were developed from the S-shaped edge-on lamellae. The growth rates of flat-on and edge-on lamellae were almost identical.

Biocompatible Materials↗

PubMed2001

A thiol proteinase inhibitor, E-64-d, corrects the abnormalities in concanavalin A cap formation and the lysosomal enzyme activity in leucocytes from patients with Chediak-Higashi syndrome by reversing the down-regulated protein kinase C activity.

We have reported previously that the abnormally down-regulated protein kinase C (PKC) causes cellular dysfunction observed in natural killer (NK) cells, polymorphonuclear leucocytes (PMNs) and fibroblasts from beige mouse, an animal model of Chediak-Higashi syndrome (CHS). Here we show that the abnormal down-regulation of PKC activity also occurs in Epstein-Barr (EB) virus-transformed cell lines from CHS patients. When CHS cell lines were stimulated with concanavalin A (Con A) for 20 min, the membrane-bound PKC activity declined markedly, whereas that in control cell lines increased. We found that E-64-d, which protects PKC from calpain-mediated proteolysis, reversed the declined PKC activity and corrected the increased Con A cap formation to almost normal levels in CHS cell lines. We confirmed that the dysregulation of PKC activity also occurred in peripheral blood mononuclear leucocytes (PBMC) from CHS patients and that E-64-d corrected both the declined PKC activity and increased Con A cap formation. E-64-d also corrected the reduced lysosomal elastase and cathepsin G activity in CHS cell lines. In contrast, chelerythrin, a specific inhibitor of PKC, and C2-ceramide, which promotes PKC breakdown induced by calpain, increased Con A cap formation and inhibited both elastase and cathepsin G activity in normal cell lines. Moreover, we found that ceramide production in CHS cell lines increased significantly after Con A stimulation, which coincides with our previous observation in fibroblasts from CHS mice. These results suggest an association between ceramide-induced PKC down-regulation and the cellular dysfunctions in CHS.

Calpain↗

PubMed2001

Useful polyclonal antibodies against synthetic peptides corresponding to immunoglobulin light chain constant region for immunohistochemical detection of immunoglobulin light chain amyloidosis.

For the immunohistochemical detection of immunoglobulin (Ig) light chain amyloidosis on formalin-fixed, paraffin-embedded tissue sections, we prepared polyclonal antibodies against synthetic peptides corresponding to positions 118-134 of Ig lambda light chain and positions 116-133 of Ig kappa light chain. Nineteen cases of systemic Ig lambda light chain amyloidosis (Alambda amyloidosis), 10 cases of systemic Ig kappa light chain amyloidosis (Akappa amyloidosis), one case of immunohistochemically unclassified systemic amyloidosis and five cases of localized Alambda amyloidosis were tested with these antibodies. Anti-lambda (118-134) antiserum and the affinity-purified antibody both reacted with 18 of the 19 cases of systemic Alambda amyloidosis and all cases of localized Alambda amyloidosis, although the immunoexpression was somewhat variable in intensity in different areas within the same specimen in both systemic and localized amyloidosis. The signal intensities in plasma cells and serum reacted for anti-lambda (118-134) antiserum were weaker than signals obtained with commercially available anti-Ig lambda light chain antibodies. Anti-kappa (116-133) antiserum and the affinity-purified antibody reacted with nine of the 10 cases of systemic Akappa amyloidosis. We conclude that these antibodies against synthetic peptides corresponding to the Ig light chain constant region are useful for the classification of amyloidosis on formalin-fixed, paraffin-embedded tissue sections.

Amyloidosis↗