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T Iida

Publications and source records attributed to T Iida.

At least 271 records · Page 15Linked to original sources
PubMed1994

The CpG island of the FMR-1 gene is methylated differently among embryonic tissues: implication for prenatal diagnosis.

We studied the methylation status of the CpG island of the FMR-1 (fragile X syndrome) gene to recognize the possibility of its prenatal diagnosis with early pregnant subjects. Southern hybridization using EcoRI/BssHII restriction enzymes double digestion was performed in the brain and chorionic villi of 8th week embryos, and the placenta and cord blood of newborns. No methylation of the FMR-1 gene occurred in both of the tissues examined in males, while 50% of the cells in females were methylated in both the brain and the cord blood, indicating that methylation occurs with inactivation of the X-chromosome in accordance with the literature. However, there was no methylation in either the chorionic villi or placenta in female as well as in males. Some extra-embryonic tissues such as the chorionic villi and the placenta escape X-chromosome FMR-1 gene inactivation and it can be the exception in the lyonization. To assess the methylation status in prenatal diagnosis, precautions are needed and they are not suitable for prenatal diagnosis.

Blotting, Southern↗
PubMed1994

Accommodation toward diameter change of a spotlight in a dark room.

The three-dimensional optometer (TDO III) was used to measure accommodative responses when gazing at a spotlight that changed its diameter in an otherwise completely dark room. Three emmetropic females served as subjects and the stimuli were presented at 33 cm (-3 D) from the subjects. The subjects felt that the spotlight approached them when its diameter increased. However, the magnitude of accommodation when viewing the smaller diameter spotlight was greater than that for the larger diameter spotlight. This means that the eye accommodated less, although the spotlight was felt to be nearer, and contradicts the common belief based on the subjectively measured data reported earlier. By conducting several supplemental experiments, we infer that this phenomenon comes from the effort in reducing accommodation lag dynamically in order to see the smaller target more clearly.

Accommodation, Ocular↗
PubMed1994

Demonstration and characterization of simultaneous production of a thermostable direct hemolysin (TDH/I) and a TDH-related hemolysin (TRHx) by a clinically isolated Vibrio parahaemolyticus strain, TH3766.

Simultaneous production of a thermostable direct hemolysin (TDH)-like toxin (TDHx) and a TDH-related hemolysin (TRH)-like toxin (TRHx) by a clinical isolate (strain TH3766) of Kanagawa phenomenon-positive Vibrio parahaemolyticus was demonstrated and characterized. The two hemolysins were differentially purified by column chromatography on hydroxyapatite and immunoaffinity columns. The molecular weight of the two hemolysins were estimated to be 23,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (PAGE). The purified TDHx was indistinguishable from the previously reported TDH/I (from strain TH012) but was different from the authentic TDH of a Kanagawa phenomenon-positive strain (T4750) physicochemically. The mobility of TRHx in nondenaturing PAGE differed from all the known TDHs and TRHs. The genes (tdhX and trhX) coding for TDHx and TRHx were cloned and sequenced. Homologies of nucleotide sequences of the coding regions between tdhX and tdhA (a gene for the authentic TDH) and between trhX and trh (a gene for the authentic TRH) were 98.1 and 99.1%, respectively, and homology between tdhX and trhX was 68.1%. At the amino acid level, TdhX was completely identical to TDH/I, although two base differences were found in the nucleotide sequences between tdhX and tdh/I. Two amino acid differences were observed between TrhX and Trh. Thus, these findings suggest that the TH3766 strain produces two types of hemolysins simultaneously. This is the first evidence that a strain of V. parahaemolyticus produces two types of toxins of the TDH-TRH family at the same time.

Amino Acid Sequence↗
PubMed1994

A mutant toxin of Vibrio parahaemolyticus thermostable direct hemolysin which has lost hemolytic activity but retains ability to bind to erythrocytes.

A mutant toxin, R7, of thermostable direct hemolysin (TDH) with a single amino acid substitution at glycine 62 was analyzed. The hemolytic activity of R7 decreased to less than 1/1,000 of that of wild-type TDH, and its mouse lethality was undetectable. This mutant toxin, however, showed a marked inhibitory effect on hemolysis by wild-type TDH. Enzyme immunoassay and flow cytometric analysis demonstrated that R7 retained approximately 50% of the ability to bind to erythrocytes compared with that of wild-type TDH, suggesting that its inhibition of hemolysis by wild-type TDH might be due to blocking the binding sites on the erythrocyte membrane. Wild-type TDH affected the erythrocyte membrane by causing an influx of calcium and propidium iodide, while R7 showed no detectable effects of these kinds. These results suggest that hemolysis by TDH consists of at least two steps, binding and postbinding, and that R7 is likely to be a postbinding activity-deficient mutant toxin of TDH.

Cell Membrane Permeability↗
PubMed1994

Cloning and characterization of a chromosomal gene cluster, pah, that encodes the upper pathway for phenanthrene and naphthalene utilization by Pseudomonas putida OUS82.

A 25-kb DNA SalI fragment cloned from the chromosomal DNA of Pseudomonas putida OUS82, which utilizes phenanthrene (Phn+) and naphthalene (Nah+), carried all of the genes necessary for upper naphthalene catabolism. Cosmid recombinant pIP7 complemented both the Nah- and Phn- defects of OUS8211 (Trp-Nah-Phn-Sal+[salicylate utilizing]Hna+[1-hydroxy-2-naphthoate utilizing]) and only the Phn- defect of OUS8212 (Trp-Nah-Phn-Sal-Hna+). The results indicate that strain OUS82 uses different pathways after o-hydroxycarboxylic aromatics in the catabolism of naphthalene and phenanthrene.

Cloning, Molecular↗
PubMed1994

Pharmacodynamics and tumoricidal effect of adriamycin entrapped in ceramide sulfate-containing liposomes.

Ceramide sulfate (N-acylsphingosine-1-O-sulfate), which lacks the galactose residue of sulfatide, was examined as a possibly preferable constituent of liposomes for drug delivery. Multilamellar vesicles prepared from phosphatidylcholine, cholesterol, and N-lignoceroylsphingosine-1-O-sulfate in a molar ratio of 5:4:1 efficiently entrapped adriamycin, and the retention of the drug in the liposomes in saline at 4 degrees C for 8 d was nearly 100%. In terms of entrapment efficiency and retention of the drug in liposomes, N-lignoceroylsphingosine-1-O-sulfate was superior to N-stearoylsphingosine-1-O-sulfate. A pharmacodynamic study revealed that the blood level of adriamycin was far higher with the drug encapsulated in N-lignoceroylsphingosine-1-O-sulfate-containing liposomes than with the free drug. The drug level in the heart was remarkably reduced with the liposome-entrapped drug, which is advantageous in reducing the cardiotoxicity of this drug. The effect of N-lignoceroylsphingosine-1-O-sulfate-containing liposomes on the blood level of adriamycin was superior to that of sulfatide-containing liposomes, though the effect of the former on the heart level was comparable to that of the latter. The tumoricidal effect on ascitic P388 leukemia and Lewis lung carcinoma was higher with adriamycin entrapped in N-lignoceroylsphingosine-1-O-sulfate-containing liposomes than with the free drug.

Animals↗
PubMed1994

Analysis of conjugated bile acids in human biological fluids. Synthesis of hyodeoxycholic acid 3- and 6-glycosides and related compounds.

The glucuronide, glucoside and N-acetylglucosaminide conjugates of hyodeoxycholic acid were synthesized. In addition, murideoxycholic acid 3-glycosides and some of their C-5 epimeric analogs were also prepared. The principal reactions used are 1) the Koenigs-Knorr condensation reaction of 3-oxo-6 alpha-hydroxy and 6-oxo-3 alpha-hydroxy esters with an appropriate alpha-acetohalosugar catalyzed by cadmium carbonate in benzene under reflux, 2) reduction of the resulting bile acid glycoside methyl ester-acetates with tert-butylamine-borane complex, and 3) subsequent hydrolysis with aqueous lithium hydroxide.

Bile Acids and Salts↗
PubMed1994

Intact sex determining region Y (SRY) in a patient with XY pure gonadal dysgenesis and a twin brother.

A patient with an apparently normal 46, XY karyotype, suffering from pure gonadal dysgenesis and of short stature was investigated. The patient, who was growth retarded, was a 30-year-old married Japanese woman with a history of primary amenorrhea and infertility with a weight of 42 kg and a height of 146 cm. She has a phenotypically and karyotypically normal dizygotic twin brother with normal development. Southern-blot and polymerase chain-reaction analyses revealed no apparent deletions in the patient's Y chromosome, including the sex-determining region Y (SRY). The DNA sequencing of the SRY gene showed a 100% nucleotide sequence identity with the reported cloned sequence. Sex reversal in the present case may be due to mutation at a locus other than SRY in the sex determining pathway, a gene potentially involved in the determination of human constitution.

Adult↗
PubMed1993

Origin of JC polyomavirus variants associated with progressive multifocal leukoencephalopathy.

JC polyomavirus (JCV) DNAs from the urine of nonimmunocompromised individuals (designated archetypal isolates) regularly contain a regulatory sequence that may have generated various regulatory sequences of JCV isolates derived from the brain of patients with progressive multifocal leukoencephalopathy (PML). In this report, we constructed a phylogenetic tree for 14 isolates (7 archetypes and 7 PML types) from DNA sequence data on the VP1 (major capsid protein) gene. According to the phylogenetic tree, the 14 isolates diverged into types A and B, each of which contained archetypal and PML-type isolates. Each type further diverged into several groups containing archetypal and PML-type isolates. We conclude that PML-type isolates are polyphyletic in their origin and do not constitute a unique lineage. This conclusion suggests that PML-type JCV isolates are generated from archetypal strains during persistence in the hosts. Furthermore, the present phylogenetic analysis indicates that an ancestral JCV carried the archetypal regulatory sequence and that this structure has been conserved in the course of JCV evolution.

Base Sequence↗
PubMed1993

Breast cancer in a male patient with prolactinoma.

A 68-year-old man was diagnosed as having left primary breast cancer. Systemic bone roentgenography showed no evident metastasis, however, skull roentgenography revealed ballooning of the sella turcica, suggesting a pituitary tumor, which was subsequently confirmed by computed tomography. Because there was a high serum prolactin level, the pituitary tumor was diagnosed as a prolactinoma. A modified radical mastectomy was performed for the breast cancer, and bromocriptine therapy given for the prolactinoma. Prolactin is known to initiate and promote breast cancer in mice and rats but little is known about its role in human breast cancer. If hyperprolactinemia plays an important role in the tumorigenesis of human breast cancer as it does in mice and rats, the incidence of breast cancer in patients with hyperprolactinemia may be high. To our knowledge, however, only four such cases have been reported. The present rare case of male breast cancer with prolactinoma is discussed with reference to the literature.

Aged↗
PubMed1993

Sex identification by polymerase chain reaction using a Y-autosome homologous primer set.

We have developed a one-step polymerase chain reaction (PCR) technique which detects a sequence on the human Y chromosome and an autosomal sequence in one reaction. The method is very reliable for the sex determination, as the detection of the autosome-specific signal ensures the presence of DNA in the specimen even in the absence of the Y-specific signal.

Base Sequence↗
PubMed1993

Potential bile acid metabolites. 20. A new synthetic route to stereoisomeric 3,6-dihydroxy- and 6-hydroxy-5 alpha-cholanoic acids.

An improved procedure for the syntheses of stereoisomeric 3,6-dihydroxy- and 6-hydroxy-5 alpha-cholanoic acids (and their methyl esters) is described. The principal reactions employed are those reported in the preceding paper of this series, with the commercially available hyodeoxycholic acid as starting material. The final step in the procedure is the reduction of the key 5 alpha C-6 ketones with either the stereoselective equatorial reagent, Li/NH3/MeOH, or the axial reagent, Zn(BH4)2. The results of analysis of the prepared 6-monohydroxylated and 3,6-dihydroxylated stereoisomers by thin-layer chromatographic, high performance liquid chromatographic and gas-liquid chromatographic mobilities, and 1H and 13C nuclear magnetic resonance spectra are discussed along with the data for the corresponding compounds in the 5 beta-series.

Bile Acids and Salts↗
PubMed1993

Potential bile acid metabolites. 19. The epimeric 3 alpha,6,7 beta-trihydroxy- and 3 alpha,6,7 beta,12 alpha-tetrahydroxy-5 alpha-cholanoic acids.

Syntheses by a new procedure of the known 3 alpha,6 alpha,7 beta- and 3 alpha,6 beta,7 beta-trihydroxy-5 alpha-cholanoic acids, and of the once-reported analog 3 alpha,6 alpha,7 beta,12 alpha-, as well as the new 3 alpha,6 beta,7 beta,12 alpha-tetrahydroxy-5 alpha-cholanoic acids, are described. Key intermediates of the syntheses are the 6-oxo-7 beta-ols of the respective 5 alpha-cholanoic acids (and their methyl esters) prepared by allomerization at C-5 of appropriate 6-bromo-7-oxo derivatives of the corresponding 5 beta-acids. Successful reduction of the 6,7-ketols to the desired products depended on the proper choice of reagents, either Zn(BH4)2 or Li/NH3/MeOH.

Ammonia↗
PubMed1993

Y chromosome analysis and laparoscopic surgery in XY pure gonadal dysgenesis: a case report and a review of literature.

DNA analysis and laparoscopic surgery were performed on a patient with 46, XY pure gonadal dysgenesis. Southern-blot and polymerase chain-reaction analyses revealed that she had no apparent deletion of the Y chromosome, including the SRY gene (sex-determining region Y), suggesting that the patient might have some other abnormality. Since the risk of gonadal neoplasia in XY gonadal dysplasia is high, operative laparoscopy was performed to ensure that there was no malignancy in the patient. Laparoscopic surgery is recommended because of the amount of the surgery and the rapid postoperative recovery of the patient.

Adult↗
PubMed1993

Origin of D-alanine present in urine of mutant mice lacking D-amino-acid oxidase activity.

Urine of mutant ddY/DAO- mice lacking D-amino-acid oxidase contained 13 times more D-alanine than that of normal ddY/DAO+ mice. Because D-alanine is a component of bacterial cell walls, the possibility that the urinary D-alanine came from intestinal bacteria was examined. In ddY/DAO- mice that were made germ free at birth and reared in a germ-free environment, the quantity of urinary D-alanine was found to be at a low level comparable to that of the normal mice. When these germ-free mice were made gnotobiotic by inoculation with gram-negative bacteria (Escherichia coli and Bacteroides vulgatus), the urinary D-alanine increased to a high level. When these gnotobiotic mice were further inoculated with gram-positive bacteria (Bifidobacterium longum and Eubacterium aerofaciens), the urinary D-alanine increased further. These results indicate that most of the urinary D-alanine of the conventionally reared ddY/DAO- mice is of gastrointestinal bacterial origin.

Alanine↗
PubMed1993

Postnatal expression of hypoxanthine guanine phosphoribosyltransferase in the mouse brain.

The distributional and activity changes of hypoxanthine guanine phosphoribosyltransferase (HGPRT) were investigated in the developing mouse brain. The HGPRT activity level was low at birth, increased rapidly during the first 7 days of life, and underwent a gradual increase thereafter to the mature level. Polyclonal antibody against HGPRT purified from mouse brain was prepared for immunohistochemical demonstration of the enzyme during brain development. In the cerebellum, part of the Purkinje cells was consistently immunostained throughout growth, and the presence of HGPRT was observed in the dendrites of mature Purkinje cells. The most dominant change in HGPRT localization was observed in the hippocampus. Little HGPRT was detectable in the newborn mouse hippocampus. At postnatal day 7, cytoplasmic HGPRT appeared sporadically in the granular cells independently of the region of the hippocampus. The number of positive immunoreactive cells increased with growth, and the dendrites of granular cells were also immunostained on postnatal day 28. Further immunostaining was noted in the granule cells of the dentate gyrus on postnatal day 35. The above results suggest that HGPRT may play an important role in the developing hippocampus. Further investigations of the HGPRT in the human hippocampus may help to clarify the mechanism underlying the neurological disorders encountered in the Lesch-Nyhan syndrome.

Aging↗