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T Noda

Publications and source records attributed to T Noda.

At least 217 records · Page 12Linked to original sources

Enolase antigen, mannan antigen, Cand-Tec antigen, and beta-glucan in patients with candidemia.

We compared the specificities and sensitivities of four tests used for the serodiagnosis of candidemia in 39 patients with candidemia, including 10 patients with superficial Candida colonization, 10 patients with deep mycosis, and 20 healthy subjects. The results obtained by the dot immunoblotting assay for detecting the enolase antigen (48 kDa) were compared with those of assays for detecting mannan antigen, heat-labile antigen (a threshold titer of four times), and beta-glucan (> or = 60 pg/ml). Enolase antigen was detected in 28 (71.8%) patients with candidemia, while 30 (76.9%), 10 (25.6%), and 27 (84.4%) patients were positive for the heat-labile antigen by the Cand-Tec assay, the mannan antigen by the Pastorex Candida assay, and beta-glucan by the limulus test, respectively. Ten patients with superficial Candida colonization, 5 patients with invasive pulmonary aspergillosis, 5 patients with cryptococcosis, and 20 healthy subjects were negative for both enolase antigen and mannan antigen. Two patients with superficial Candida colonization, one patient with invasive pulmonary aspergillosis, and two patients with cryptococcosis were positive by the Cand-Tec assay. The beta-glucan concentration was more than 60 pg/ml in all patients with invasive pulmonary aspergillosis; however, it was less than 10 pg/ml in all patients with cryptococcosis. The specificity of enolase antigen in the serodiagnosis of candidemia was 100%, but the sensitivity was 71.8%. The specificity and sensitivity of Cand-Tec, the assay for mannan antigen, and the assay for beta-glucan were 76.9 and 87.5%, 25.6 and 100%, and 84.4 and 87.5%, respectively. Our results demonstrated that antigen detection tests are useful for the diagnosis of candidemia; however, none is satisfactory for the serodiagnosis of candidemia. We suggest that a combination of two assays may increase the accuracy of diagnosis of candidiasis.

Adult↗

[Tooth movement by biomechanical technique in orthodontic treatment].

The purpose of this study was to analyze tooth movement by measuring the electric impedance of the wire and by using the nonlinear finite element analysis. In this study, the HP4338A Milliohmmeter was used and the model consisted of a metal tooth, silicone bath, bracket, and orthodontic wire. Then, the two-dimensional finite elements were used and the model consisted of tooth, periodontal ligament, alveolar bone, bracket, and orthodontic wire. There were two analyses. The first was the contact nonlinear finite element analysis of elastic deformation in the displaced tooth at the slide points between the bracket and wire where two gap element areas existed, and the second was the material nonlinear finite element analysis of the stress relaxation in bone at the fixing points between the bracket and wire where two rigid element areas, differing from the gap element areas, existed. The results were as follows: 1. The linear proportion between the electric impedance and the orthodontic wire was found. Therefore very minute tooth movements became measurable with changes of the wire electric impedance. 2. During tooth movement, the stick between the bracket and the wire altered with the slip ones repeatedly. 3. The movement of the displaced tooth at the center of rotation was counterclockwise. 4. The movement of the displaced tooth at the bracket position was clockwise.

Biomechanical Phenomena↗

[CGH (comparative genomic hybridization)].

Comparative Genomic Hybridization (CGH) is a powerful new method which allows genome-wide mapping of regions with DNA sequence copy number changes (both increases and decreases) in a single experiment without previous knowledge of the locations of the regions of abnormality. CGH is based on in situ hybridization of differentially labeled total genomic tumor DNA and normal DNA to normal human metaphase chromosomes. After hybridization copy number variations among the sequences in the tumor DNA are detected by measuring the tumor/normal fluorescence intensity ratio for each locus in the target chromosomes. Many previously unknown chromosomal regions with relative copy number changes have been detected in various tumors by CGH. Some changes have been identified as genetic markers associated with biological and clinico-pathological characteristics (i.e., histopathological grade, and clinical outcome). We review the published CGH articles and discuss briefly on current progress in CGH analysis to ovarian and uterine cervical cancer in our laboratory.

DNA, Neoplasm↗

Postnatal development of periodontal ruffini endings in rat incisors: an immunoelectron microscopic study using protein gene product 9.5 (PGP 9.5) antibody.

Postnatal development of Ruffini endings was ultrastructurally investigated in the upper incisors of the rat from 1 day to 60 days after birth by means of protein gene product 9.5 (PGP 9.5) immunocytochemistry. The immunostaining with PGP 9.5 antibody clearly demonstrated chronological alterations of the distribution and ultrastructure of the Ruffini endings during postnatal development. At 1 day after birth, the PGP 9.5-positive nerve terminals contained a few mitochondria and vesicles immunonegative for PGP 9.5. Dendritic terminals appeared at 4 days after birth, with a small number of expanded or bulbous portions. These expanded portions possessed morphological features similar to those of the growth cone: several mitochondria and various kinds of vesicles. Typical Ruffini endings with dendritic ramification and expanded portions appeared 7-11 days after birth. At this stage, parts of the axon terminals extended through the slits of Schwann cell covering and formed finger-like projections called axonal spines. These Ruffini endings increased dramatically in number after 24-26 days and were identical in density and morphology to those seen in adult rats. After the commencement of the occlusion between the incisors, the number of large mitochondria increased, in contrast to the decrease of the vesicles in the axon terminals. Moreover, the axonal spines increased both in number and in length. Thus, the periodontal nerve endings showed stage-specific morphological features intimately related in timing to tooth eruption and occlusion. Functional stimuli possibly contribute to the final differentiation and maturation of the periodontal Ruffini endings.

Age Factors↗

Increased soluble form of P-selectin in patients with unstable angina.

BACKGROUND: P-selectin in platelets and endothelial cells mediates adhesive interaction with leukocytes to form thrombi. The purpose of the present study was to investigate the plasma levels of P-selectin in patients with unstable angina and in those with stable effort angina of different pathophysiologies. METHODS AND RESULTS: Plasma P-selectin levels were determined by a monoclonal antibody-based enzyme immunoassay on plasma samples taken from 12 patients with unstable angina, 11 patients with stable effort angina, and 15 healthy volunteers. Patients with unstable angina had angina at rest associated with ECG changes. In patients with unstable angina, plasma P-selectin levels within 1 hour (361 +/- 90 ng/mL) and at 3 hours (282 +/- 56 ng/mL) after angina were significantly (P < .05) higher than those in volunteers (177 +/- 31 ng/mL). Plasma P-selectin levels at 5 hours after attack (242 +/- 46 ng/mL) did not differ from those in volunteers. Although patients with stable effort angina developed angina with ST-segment depressions by treadmill exercise, their plasma P-selectin levels did not change (before, 178 +/- 45; immediately after, 186 +/- 36; and 1 hour after the exercise, 179 +/- 34 ng/mL). CONCLUSIONS: Plasma P-selectin levels after angina increased significantly in patients with unstable angina but did not in patients with stable effort angina. These findings may contribute to understanding of the pathophysiology of the acute coronary syndrome of unstable angina.

Aged↗

Human alanyl-tRNA synthetase: conservation in evolution of catalytic core and microhelix recognition.

The class II Escherichia coli and human alanyl-tRNA synthetases cross-acylate their respective tRNAs and require, for aminoacylation, an acceptor helix G3:U70 base pair that is conserved in evolution. We report here the primary structure and expression in the yeast Pichia of an active human alanyl-tRNA synthetase. The N-terminal 498 amino acids of the 968-residue polypeptide have substantial (41%) identity with the E. coli protein. A closely related region encompasses the class-defining domain of the E. coli enzyme and includes the part needed for recognition of the acceptor helix. As a result, previously reported mutagenesis, modeling, domain organization, and biochemical characterization on the E. coli protein appear valid as a template for the human protein. In particular, we show that both the E. coli enzyme and the human enzyme purified from Pichia aminoacylate 9-base pair RNA duplexes whose sequences are based on the acceptor stems of either E. coli or human alanine tRNAs. In contrast, the sequences of the two enzymes completely diverge in an internal portion of the C-terminal half that is essential for tetramer formation by the E. coli enzyme, but that is dispensable for microhelix aminoacylation. This divergence correlates with the expressed human enzyme behaving as a monomer. Thus, the region of close sequence similarity may be a consequence of strong selective pressure to conserve the acceptor helix G3:U70 base pair as an RNA signal for alanine.

Alanine-tRNA Ligase↗

Improved detection of nitric oxide radical (NO.) production in an activated macrophage culture with a radical scavenger, carboxy PTIO and Griess reagent.

An improved method for the detection of nitric oxide radicals (NO. in cultures of activated macrophages was developed, involving a nitric oxide radical scavenger, 2-(4-carboxyphenyl)-4,4,5,5- tetramethylimidazoline-3-oxide-1-oxyl (carboxy PTIO) and Griess reagent. A murine macrophage-like cell line, J774.1, was activated with interferon-gamma (IFN-gamma) and bacterial lipopolysaccharide (LPS), which induced the production and secretion of NO2- into the culture supernatant. Addition of carboxy PTIO to the activated macrophages increased the amount of NO2- to 4- to 5-fold without cell damages, probably because carboxy PTIO rapidly reacted with NO. to form NO2-, which was finally assayed by the Griess reaction.

Amino Acid Oxidoreductases↗

Subcellular localization of the APC protein: immunoelectron microscopic study of the association of the APC protein with catenin.

Mutations in the APC gene are linked to the development of sporadic colorectal tumors as well as to familial adenomatous polyposis. Recently, the APC protein was reported to associated with catenins, proteins that bind to the cell adhesion molecule E-cadherin. In the present study, we examined the distribution and localization of the APC protein and alpha -catenin in the normal mouse intestine by light and immunoelectron microscopy using specific antibodies. The APC protein was found to be localized in microvilli and in the apical and lateral cytoplasm of the epithelial cells, whereas alpha-catenin was detected only in the lateral cytoplasm. Double-labeling immunoelectron microscopy showed colocalization of the APC protein with alpha-catenin in the lateral cytoplasm, especially along the lateral plasma membrane, although a certain portion of the APC protein in this region was distributed independently of alpha-catenin. These results suggest that a portion of the APC protein localized in the lateral cytoplasm of intestinal epithelial cells functions in cooperation with catenins, whereas the APC protein in microvilli and in the apical cytoplasm has other functions independent of catenins.

Adenomatous Polyposis Coli Protein↗

Ca(2+)-induced Ca2+ release in myocytes from dyspedic mice lacking the type-1 ryanodine receptor.

While subtypes 1 and 2 of the ryanodine receptor (RyR) function as intracellular Ca2+ release channels, little is known about the function of the third subtype (RyR-3), first identified in brain. Myocytes from mice homozygous for a targeted mutation in the RyR-1 gene (dyspedic mice) can now be used for a study on the function of RyR-3, which is predominantly expressed in these cells according to our reverse transcription-polymerase chain reaction analysis. We here demonstrate in these myocytes caffeine-, ryanodine- and adenine nucleotide-sensitive Ca(2+)-induced Ca2+ release with approximately 10 times lower sensitivity to Ca2+ than that of RyR-1. Although RyR-3 does not mediate excitation-contraction coupling of the skeletal muscle type, we propose that RyR-3 may induce intracellular Ca2+ release in response to a Ca2+ rise with a high threshold.

Adenine Nucleotides↗

Novel system for monitoring autophagy in the yeast Saccharomyces cerevisiae.

The yeast S. cerevisiae imports cytosolic components into the vacuole non-selectively by autophagy and degrades them by vacuolar hydrolases under nutrient starvation conditions. We developed a novel system for monitoring autophagy by constructing cells in which modified vacuolar alkaline phosphatase is expressed as an inactive precursor form in the cytosol. Under starvation conditions, the processing of the precursor to the mature form and phosphatase activity appeared gradually, and the mature form was located in the vacuole. Disruption of APG1, an essential gene for autophagy, resulted in no processing or phosphatase activity. These results indicate that the precursor form in the cytosol is transferred to the vacuole by autophagy and converted to the active form by vacuolar proteinases. Thus, autophagy could be determined easily and accurately by measuring the phosphatase activity.

Alkaline Phosphatase↗

Abnormal junctions between surface membrane and sarcoplasmic reticulum in skeletal muscle with a mutation targeted to the ryanodine receptor.

Junctions that mediate excitation-contraction (e-c) coupling are formed between the sarcoplasmic reticulum (SR) and either the surface membrane or the transverse (T) tubules in normal skeletal muscle. Two structural components of the junctions, the feet of the SR and the tetrads of T tubules, have been identified respectively as ryanodine receptors (RyRs, or SR calcium-release channels), and as groups of four dihydropyridine receptors (DHPRs, or voltage sensors of e-c coupling). A targeted mutation (skrrm1) of the gene for skeletal muscle RyRs in mice results in the absence of e-c coupling in homozygous offspring of transgenic parents. The mutant gene is expected to produce no functional RyRs, and we have named the mutant mice "dyspedic" because they lack feet--the cytoplasmic domain of RyRs anchored in the SR membrane. We have examined the development of junctions in skeletal muscle fibers from normal and dyspedic embryos. Surprisingly, despite the absence of RyRs, junctions are formed in dyspedic myotubes, but the junctional gap between the SR and T tubule is narrow, presumably because the feet are missing. Tetrads are also absent from these junctions. The results confirm the identity of RyRs and feet and a major role for RyRs and tetrads in e-c coupling. Since junctions form in the absence of feet and tetrads, coupling of SR to surface membrane and T tubules appears to be mediated by additional proteins, distinct from either RyRs or DHPRs.

Animals↗

Placental defect and embryonic lethality in mice lacking hepatocyte growth factor/scatter factor.

Hepatocyte growth factor/scatter factor (HGF/SF) functions as a mitogen, motogen and morphogen for a variety of cultured cells. The genes for HGF/SF and its receptor (the c-met proto-oncogene product) are expressed in many tissues during the embryonic periods and in the adult. HGF/SF is thought to mediate a signal exchange between the mesenchyme and epithelia during mouse development. To examine the physiological role of HGF/SF, we generated mutant mice with a targeted disruption of the HGF/SF gene. Here we report that homozygous mutant embryos have severely impaired placentas with markedly reduced numbers of labyrinthine trophoblast cells, and die before birth. The growth of trophoblast cells was stimulated by HGF/SF in vitro, and the HGF/SF activity was released by allantois in primary culture of normal but not mutant embryos. These findings suggest that HGF/SF is an essential mediator of allantoic mesenchyme-trophoblastic epithelia interaction required for placental organogenesis.

Allantois↗

bcl-2 deficiency in mice leads to pleiotropic abnormalities: accelerated lymphoid cell death in thymus and spleen, polycystic kidney, hair hypopigmentation, and distorted small intestine.

Transgenic mice homozygously lacking in the bcl-2 gene were generated using homologous recombination in embryonal stem cells. The complete absence of Bcl-2 alpha and -beta proteins did not interfere with normal embryonic development. Abnormalities became evident after birth, although the severity varied among homozygous null mice, bcl-2-/- mice displayed pleiotropic abnormalities similar to those in the previously described bcl-2-/- mice, including growth retardation, smaller ears, short lives, polycystic kidney, atrophic thymus and spleen with accelerated apoptotic cell death of lymphocytes, and hair hypopigmentation in the second hair follicle cycle. Our bcl-2-/- mice also revealed novel defects in the small intestine, characterized by retarded development, accelerated exfoliation of epithelial cells, and very few mitotic progenitor cells.

Abnormalities, Multiple↗

The adverse effects of oral 2-mercaptobenzimidazole on pregnant rats and their fetuses.

The effects of oral 2-mercaptobenzimidazole (2-MBI) on pregnant Wistar rats were examined. In a preliminary dose-finding study, pregnant rats treated with 2-MBI over Days 7-17 of gestation showed reduction in maternal thymus weights with compound-related mortality at doses > or = 40 mg/kg. No adverse effects on fetuses were found at doses < or = 40 mg/kg. However, anasarca, cleft palate, and dilated lateral ventricles were present in all fetuses from the only survivor among the dams treated with 60 mg/kg of 2-MBI. In the teratology study, pregnant rats were treated with 2-MBI at doses of 0, 3.3, 10, and 30 mg/kg during the period of organogenesis (Gestation Days 7-17). In addition, pregnant rats of three groups were also treated with 60 mg/kg of 2-MBI for 3 or 4 days during specific periods of organogenesis (Days 7-10, 11-14, or 15-17 of gestation). Treatment on Gestation Days 7-17 resulted in reduced maternal thymus weights at doses of > or = 3.3 mg/kg. In addition to reduced fetal weights, visceral variations (kinked ureter and dilated renal pelvis) and delayed ossification were seen in the fetuses at doses > or = 10 mg/kg, and skeletal variations (rudimentary lumbar ribs) were seen at 30 mg/kg. In the fetuses from the dams treated with 60 mg/kg of 2-MBI, rudimentary lumbar ribs were seen mainly in the group treated on Days 7-10 of gestation, whereas kinked ureter and dilated renal pelvis were evident mainly in the group treated on Gestation Days 15-17.(ABSTRACT TRUNCATED AT 250 WORDS)

Abnormalities, Drug-Induced↗

Peritoneal lavage versus drainage for perforated appendicitis in children.

A total of 231 children with acute appendicitis were treated at our hospitals during the 10 years between 1984 and 1993, 53 of whom had a perforated appendix. These 53 patients were randomly assigned to two groups at the time of surgery according to the different procedures performed. Thus, 29 children were managed by appendectomy followed by peritoneal lavage using a large amount of saline, and intravenous antibiotic therapy consisting of aminoglycoside and cephem (lavage group), while the other 24 children were treated by appendectomy with silicon tube drainage and the same systemic antibiotic therapy (drainage group). The mean length of hospitalization, and the mean durations of fever and the need for fasting after laparotomy in the lavage group were significantly less than those in the drainage group: 10.1 versus 18.8 days, 2.8 versus 7.7 days, and 1.8 versus 3.5 days, respectively. The operation wounds healed well in the lavage group due to the fact that there was no drain. Wound infections occurred in two children from the lavage group and six from the drainage group. Intra-abdominal abscesses occurred in two children from the drainage group. Accordingly, peritoneal lavage appears to be superior to intraperitoneal tube drainage for the management of perforated appendicitis in children.

Adolescent↗

Biliary complications after excisional procedure for choledochal cyst.

During the last 25 years, from 1969 to 1994, the authors treated 97 choledochal cysts by surgical excision. Biliary reconstruction consisted of 67 hepaticoduodenostomies and 30 hepaticojejunostomies. The common hepatic duct was the site of anastomosis in 9 of the duodenostomies and 13 of the jejunostomies and of the bifurcation of the hepatic ducts in 58 duodenostomies and 17 jejunostomies. Reoperation was required in 10 cases because of recurrent cholangitis with intrahepatic gallstones. Biliary strictures were responsible for the cholangitis in 9 children with anastomoses at the level of the common hepatic duct and in 1 with an anastomosis at the level of the bifurcation. These results suggest that biliary complications develop because of anastomotic stricture or primary ductal stricture, and may be minimised by the creation of a wide anastomosis, which is best accomplished at the hepatic hilum.

Adolescent↗

Alveolar rhabdomyosarcoma of the lung in a child.

The case of a 22-month-old boy with alveolar rhabdomyosarcoma of the lung is presented. Brain metastasis and recurrence of the right pulmonary hilum and parietal pleura developed 6, 11, and 24 months (respectively) after tumor resection. Chemotherapy and radiotherapy were effective. Neuron-specific enolase was very helpful in detecting metastasis and disease recurrence. Primary pulmonary rhabdomyosarcoma can be divided into two groups: tumor in the normal lung, and tumor in cystic lesions of the lung.

Biomarkers, Tumor↗