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T Ogata

Publications and source records attributed to T Ogata.

At least 91 records · Page 5Linked to original sources
PubMed2000

Genetic evidence for a novel gene(s) involved in urogenital development on 10q26.

BACKGROUND: Although the frequent association between distal 10q monosomy and urogenital anomalies suggests the presence of a gene(s) for urogenital development on distal 10q, molecular deletion mapping has not been performed for the putative gene(s). In this study, we examined genotype-phenotype correlations in patients with distal 10q monosomy. METHODS: This study consisted of six karyotypic males (cases 1 through 6) and four karyotypic females (cases 7 through 10) with 10q26 monosomy. Cases 3 through 5 and 7 through 10 had urinary anomalies such as vesicoureteral reflux and hypoplastic kidney, and cases 1 through 6, 8, and 9 exhibited genital anomalies such as micropenis, hypospadias, cryptorchidism, and hypoplastic labia majora. Fluorescence in situ hybridization (FISH) for 10q telomere, whole chromosome 10 painting, and microsatellite analysis for 35 loci on distal 10q were performed in cases 1 through 8. RESULTS: FISH and whole chromosome painting confirmed distal 10q monosomy in cases 1 through 8. Microsatellite analysis revealed that hemizygosity for the region distal to D10S186 was shared by cases with urinary anomalies and that for the region distal to D10S1248 was common to cases with genital anomalies. Furthermore, it was indicated that PAX2, GFRA1, and EMX2 on distal 10q, in which the deletions could affect urinary and/or genital development, were present in two copies in cases 1 through 8. CONCLUSIONS: The results suggest that a novel gene(s) for urinary development and that for genital development reside in the approximately 20 cM region distal to D10S186 and in the approximately 10 cM region distal to D10S1248, respectively, although it remains to be determined whether the two types of genes are identical or different.

Adolescent↗
PubMed2000

CAG repeat length of the androgen receptor gene in Japanese males with cryptorchidism.

We have analysed the CAG repeat length in exon 1 of the androgen receptor gene in 48 Japanese males with cryptorchidism and 100 fertile Japanese males. The CAG repeat length was 23.4 +/- 0.48 (mean +/- SE) (range 16-32, median 23) in cryptorchid patients and 23.5 +/- 0.29 (range 15-32, median 23) in normal males. There was no significant difference between the two groups. The expansion of the CAG repeats in exon 1 of the androgen receptor gene is unlikely to constitute a major cause of cryptorchidism.

Adolescent↗
PubMed2000

16S-23S rDNA spacer of Pectinatus, Selenomonas and Zymophilus reveal new phylogenetic relationships between these genera.

The 16S-23S rDNA spacer regions of two Pectinatus species, two Zymophilus species and one Selenomonas species were cloned after PCR amplification. The results of PCR amplification showed that these species had two types of spacer regions which differ in molecular size (long and short). Only the long spacer regions in these bacteria contained one or two tRNA genes (alanine and/or isoleucine). The spacer regions in these bacteria had a relatively high level of homology. Homology was particularly high for bacteria belonging to the same genus. Interestingly, the order of the two tRNA genes present in the long spacer regions of Pectinatus and Selenomonas was the reverse of that which had been previously reported for other bacteria. The results of spacer homology analysis and the order of the tRNA genes suggest that the taxonomic classification of anaerobic bacteria isolated from the brewing process should be re-examined.

Beer↗
PubMed2000

Cascading glia reactions: a common pathomechanism and its differentiated control by cyclic nucleotide signaling.

A pathological glia activation, stimulated by inflammatory proteins, beta-amyloid, or brain ischemia, is discussed as a common pathogenic factor for progressive nerve cell damage in vascular and Alzheimer dementia. A critical point seems to be reached, if the cytokine-controlled microglial upregulation causes a secondary activation of astrocytes which loose the negative feedback control, are forced to give up their physiological buffering function, and may add to neuronal damage by the release of nitric oxide (NO) and by promoting toxic beta-amyloid formation. A strengthening of the cyclic adenosine-5',3'-monophosphate (cAMP) signaling exerted a differential inhibition of the stimulatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) released from cultured rat microglia, but maintained the negative feedback signal IL-6; cAMP inhibited also the release of free oxygen radicals (OR) but not of NO. Reinforcement of the NO-induced cyclic guanosine monophosphate (cGMP) increase by blockade of the phosphodiesterase (PDE) subtype-5 with propentofylline counterbalanced the toxic NO action that causes with OR neuronal damage by peroxynitrate formation. In rat cultured astrocytes, a prolonged cAMP elevation favored cell differentiation, the expression of a mature ion channel patter, and an improvement of the extracellular glutamate uptake. Cyclic AMP signaling could be strengthened by PDE blockade and by raising extracellular adenosine, which stimulates A2 receptor-mediated cAMP synthesis. Via an A1 receptor-mediated effect, elevated adenosine was found to overcome a deficient intracellular calcium mobilization resulting from an impaired muscarinic signaling at pathologically decreased acetylcholine concentrations. We suggest that pharmaca, which elevate extracellular adenosine and/or block the degradation of cyclic nucleotides, may be used to counteract glia-related neuronal damage in dementing processes.

Alzheimer Disease↗
PubMed2000

FISH deletion mapping defines a single location for the Y chromosome stature gene, GCY.

At least 1 in 1000 males lacks part of the long arm of the Y chromosome. This chromosomal aberration is often associated with short stature and infertility. Deletion mapping and genotype-phenotype analysis have previously defined two non-overlapping critical regions for growth controlling gene(s), GCY(s), on the euchromatic portion of the Y chromosome long arm. These initial mapping assignments were based on the analysis of patients carrying a pure 46,XYq- karyotype as defined by classical cytogenetic karyotyping. Four genes have been assigned to the distal one of the two critical regions. To determine whether one or both of these two critical regions harbours GCY and whether one of the four genes assigned to the distal region is involved in determination of stature, nine adult patients with Yq chromosomal abnormalities were studied in detail. By PCR and FISH analysis, we showed that all patients with a previously defined pure 46,XYq- karyotype are actually mosaics with cells containing an idic(Y) or ring(Y) chromosome in association with 45,X0 cells. This leads us to conclude that (1) FISH is an absolute prerequisite for the correct identification of Y chromosomal rearrangements and (2) only patients with interstitial Y deletions are reliable predictors for the physical location of stature gene(s) on Yq. Our molecular analyses of chromosomes from patients with interstitial Yq deletions finally establishes the proximal interval between markers DYZ3 and DYS11 as the only GCY critical interval. No functional gene has so far been identified in this region adjacent to the centromere.

Adult↗
PubMed2000

Novel mutations of the autoimmune regulator gene in two siblings with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy.

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) is the first multiple autoimmune disease that has been shown to be caused by mutations of a single gene named autoimmune regulator (AIRE). Fourteen different mutations of the AIRE gene have been identified in 61 patients from 55 families with APECED. However, there has been no report documenting AIRE gene mutations in the Asian population. We report on 2 siblings with variable manifestations of APECED who were born to a Japanese mother and a Korean father. The 11yr-old girl had intractable thrush and ungual candidiasis, hypoparathyroidism, and occipital alopecia. The 9-yr-old boy had mild ungual candidiasis alone. Direct sequencing revealed novel frameshift mutations of the AIRE gene: an insertion of a cytosine at nucleotide 29635 at the exon 10 (29635insC), which should lead to a premature termination at the codon 371, producing a truncated protein missing the second plant homeodomain-type zinc finger motif and the third LXXLL motif, and a deletion of a guanine at nucleotide 33031 at the exon 13 (33031delG), which should result in a premature termination at the codon 520, yielding a truncated protein missing the third LXXLL motif. The mother was heterozygous for 29635insC, and the father was heterozygous for 33031delG. The frameshift mutations were undetected in 40 alleles of 20 Japanese control subjects. The results imply that the C-terminus of AIRE protein including the third LXXLL motif plays a critical role in the development of APECED, and that the phenotypic spectrum can vary between siblings with the same mutations.

Child↗
PubMed2000

Short stature homeobox-containing gene duplication on the der(X) chromosome in a female with 45,X/46,X, der(X), gonadal dysgenesis, and tall stature.

We report on a Japanese female with 45,X[40]/46,X, der(X)[60], primary amenorrhea, and tall stature. She was confirmed to have complete gonadal dysgenesis at 19 yr of age and was placed on hormone replacement therapy. Growth assessment revealed that she had a low normal height until her early teens, but continued to grow with a nearly constant height velocity in her late teens, attaining a final height of 172 cm (+ 2.9 SD), which surpassed her target height range. Fluorescence in situ hybridization analysis for 10 loci/regions on the X-chromosome together with the whole X-chromosome and the Xp-specific and Xq-specific paintings showed that the der(X) chromosome was associated with duplication of roughly distal half of Xp, including SHOX (short stature homeobox-containing gene), and deletion of most of Xq. Microsatellite analysis for eight loci at Xp22 and nine loci at Xq26-28 indicated that the normal X-chromosome was of maternal origin, and the der(X) chromosome was of paternal origin. The results, in conjunction with the adult height data in 47,XXX, 46,XX gonadal dysgenesis, 47,XXY, 46,XY gonadal dysgenesis, and 46,X, idic(Xq-), suggest that the tall stature of this female is caused by the combined effects of SHOX duplication on the der(X) chromosome and gonadal estrogen deficiency. Furthermore, the similarity in the growth pattern between this female and patients with estrogen resistance or aromatase deficiency implies that the association of an extra copy of SHOX with gonadal estrogen deficiency may represent the further clinical entity for tall stature resulting from continued growth in late teens or into adulthood.

Adult↗
PubMed2000

Sex-determining gene(s) on distal 9p: clinical and molecular studies in six cases.

We report on clinical and molecular findings in five karyotypic males (cases 1-5) and one karyotypic female (case 6) with distal 9p monosomy. Cases 1-3 and 6 had female external genitalia, case 4 showed ambiguous external genitalia, and case 5 exhibited male external genitalia with left cryptorchidism and right intrascrotal testis. Gonadal explorations at gonadectomy in cases 3 and 4 revealed that case 3 had left streak gonad and right agonadism, and case 4 had bilateral hypoplastic testes. Endocrine studies in cases 1-4 and 6 showed that cases 1, 3, and 6 had definite primary hypogonadism, with basal FSH levels of 54, 39, and 41 IU/L, respectively, whereas case 2 with severe malnutrition was unremarkable for the baseline values, and case 4 had fairly good testicular function. Fluorescence in situ hybridization and microsatellite analyses demonstrated that all cases had hemizygosity of the 9p sex-determining region distal to D9S1779, with loss of the candidate sex-determining genes DMRT1 and DMRT2 from the abnormal chromosome 9. Sequence analysis in cases 1-4 and 6 showed that they had normal sequences of each exon of DMRT1 and the DM domain of DMRT2 on the normal chromosome 9, and that cases 1-4 had normal SRY sequence. The results provide further support for the presence of a sex-determining gene(s) on distal 9p and favor the possibility of DMRT1 and/or DMRT2 being the sex-determining gene(s). Furthermore, as hemizygosity of the 9p sex-determining region was associated with a wide spectrum of gonadogenesis from agonadism to testis formation in karyotypic males and with primary hypogonadism regardless of karyotypic sex, it is inferred that haploinsufficiency of the 9p sex-determining gene(s) primarily hinders the formation of indifferent gonad, leading to various degrees of defective testis formation in karyotypic males and impaired ovary formation in karyotypic females.

Adult↗
PubMed2000

Left atrial systolic function assessed by left atrial ejection force in patients with sick sinus syndrome and paroxysmal atrial fibrillation.

We evaluated left atrial systolic function using left atrial ejection force (LAEF) in 19 patients with sick sinus syndrome (SSS) and in 20 with paroxysmal atrial fibrillation (Paf) whose ages ranged from 48 to 80 years. We also evaluated 35 normal individuals for comparison. The LAEF was calculated as 1/3 x mitral valve area x (peak velocity of A wave)2 using two-dimensional and pulsed-Doppler echocardiography according to Newton's law of motion and hydrodynamics. In normal individuals, LAEF positively correlated with age (r = 0.82, p < 0.01). Normal LAEF was calculated as 0.098 x age - 0.74 (kdynes) from the regression line. Because of this correlation, we used age-corrected LAEF (%LAEF) that was calculated as (measured LAEF / normal LAEF) x 100. The results showed that this value was 53+/-26% in patients with SSS and 54+/-26% in patients with Paf. Both were significantly lower than normal individuals (p < 0.001). Among SSS subtypes, %LAEF was lower in types II and III than in type I (51+/-14%, 37+/-19%, and 81+/-35%, respectively). In conclusion, left atrial systolic function is depressed in patients with Paf and SSS, in particular, types II and III. These results suggest that the pathological abnormalities extend not only to the sinus node but also to the left atrial muscle in patients with SSS and Paf.

Aged↗
PubMed2000

Morphological changes of Babesia gibsoni grown in canine red blood cell-substituted severe combined immune deficiency mice.

Canine red blood cell-substituted severe combined immune deficiency (Ca-RBC-SCID) mice were prepared for canine Babesia gibsoni infection. The Ca-RBC-SCID mice infected with B. gibsoni developed a high level of parasitemia, and showed clinical symptoms such as anemia and hemoglobinuria, which are similar to those observed in dogs infected with B. gibsoni. The B. gibsoni parasites grown in Ca-RBC-SCID mice showed marked morphological changes, including a significantly larger size of parasites than those in dogs and abundant RBCs containing 4, 8, 16, and 32 parasites. The multiple infection may have resulted from 1 parasite because the posterior end of each parasite in a multiply infected cell was connected. The parasites grown in SCID mice retained their infectivity and virulence to dogs and their morphology was dramatically restored to the original state when they were returned to dogs.

Animals↗
PubMed2000

Fluid flow-induced tyrosine phosphorylation and participation of growth factor signaling pathway in osteoblast-like cells.

To investigate how mechanical loading stimulates bone cells, we subjected murine osteoblast-like cells, MC3T3E1, to fluid flow generated by shaking culture dishes. Since we had previously found that egr-1 mRNA is up-regulated by the flow, and that the regulation involves tyrosine kinase, we examined which proteins are tyrosine-phosphorylated by flow. Western blotting and immunoprecipitation of cell lysates showed tyrosine phosphorylation enhancement of many proteins, including ERK2 and Shc, and activation of ERK1/2. Although these responses did not occur in serum-free media, addition of EGF or bFGF recovered the responses. AG1478, an inhibitor of EGF receptor kinase activity, abolished tyrosine phosphorylation enhancement, ERK1/2 activation, and egr-1 mRNA accumulation induced by the flow of EGF-containing serum-free media. These results suggest that growth factor signaling pathways are involved in these responses. Repetition of fluid flow induced repeatedly up-regulation of egr-1 mRNA. Such events may also occur in bone under mechanical loading.

Adaptor Proteins, Signal Transducing↗
PubMed1999

Random X-inactivation in a girl with duplication Xp11.21-p21.3: report of a patient and review of the literature.

We describe a 10-month-old girl with abnormal clinical findings and Xp duplication. She showed poor weight gain and developmental retardation, and had several minor anomalies including pigmentary dysplasia (hypomelanosis of Ito). She had a partial short arm duplication in the paternally derived X chromosome, 46,X,dup(X)(p11. 21p21.3), with the normal and duplicated X chromosomes randomly inactivated. These findings indicate that gross functional imbalance in the cells with an active dup(X) chromosome has caused global developmental defects in the patient, and that functional chromosomal mosaicism with respect to the duplicated Xp region has resulted in pigmentary dysplasia. Literature review of 52 patients with partial X duplications revealed (1) random or skewed but not completely selective X-inactivation in 9 of 45 patients examined for the X-inactivation pattern, independently of the size or location of duplicated segments, (2) apparently normal phenotype in 6 of 9 patients with random or skewed X-inactivation, and (3) an abnormal phenotype in 13 of 35 patients with completely selective inactivation of dup(X) chromosomes.

Abnormalities, Multiple↗
PubMed1999

Substance P regulates the function of rabbit cultured osteoclast; increase of intracellular free calcium concentration and enhancement of bone resorption.

The effects of substance P on cultured rabbit osteoclasts were investigated. The intracellular Ca(2+) concentration ([Ca(2+)](i)) which was monitored by the microfluorometric technique using fura-2, in osteoclasts elevated by the addition of substance P (0.3-5 microM). The EC(50) value of substance P was about 200 nM. This substance P-evoked [Ca(2+)](i) elevation was not observed in the Ca(2+)-free medium. Simultaneous application of spantide, a substance P receptor antagonist, blocked the Ca(2+) response. The addition of substance P (0.1-10 microM) to cultured osteoclasts enhanced their bone resorption activity which was evaluated by the pit formation assay. Maximum enhancement of the pit formation by substance P (5 microM) peaked at about 170% of the control level. The addition of substance P receptor antagonists also inhibited the enhancement of the bone resorption by substance P addition. Substance P possibly stimulates the bone remodeling by osteoclasts via the [Ca(2+)](i) elevation.

Analysis of Variance↗
PubMed1999

Mental stress test is an effective inducer of vasospastic angina pectoris: comparison with cold pressor, hyperventilation and master two-step exercise test.

BACKGROUND: Cold pressor, hyperventilation and exercise stress tests were usually used for inducing an angina attack in patients with vasospastic angina pectoris. We induced vasospastic angina attack using the mental calculation stress test, and compared the results with those using other stress tests. SUBJECTS AND METHODS: Subjects were 29 patients with vasospastic angina pectoris. Their ages were 60.8+/-8.4 years. Coronary vasospasm was induced by an acetylcholine infusion test during coronary angiography. The mental stress test was performed as follows; after memorizing six digits numbers, they repeated these numbers in reverse for 5 min, and performed serial subtraction of 17 from 1000 for 5 min. Blood pressure, heart rate and ECG were recorded every 1-5 min during the mental stress test. The serum concentrations of epinephrine and norepinephrine were measured before and during the mental stress test. We compared these results with those obtained using cold pressor, hyperventilation and the Master two-step exercise stress test. RESULTS: (1) Eight of the 29 patients (28%) showed ischemic ST-T change, which was caused by the mental stress test. (2) The increase in norepinephrine was greater in patients with an ST-T change than without an ST-T change (0.11+/-0.06 vs. 0.04+/-0.04 ng/ml, P<0.01). (3) The incidence of the ST-T change caused by the mental stress test (28%) was similar to the cold pressor test (27%) and greater than that caused by the hyperventilation test (13%). The incidence of ST-T change caused by the Master two-step test was 55%. CONCLUSIONS: The mental stress test is an effective inducer of vasospastic angina attack, and attack may be induced by neurohumoral vasoconstrictive reflex and/or increased left ventricular afterload.

Acetylcholine↗