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T Yanagihara

Publications and source records attributed to T Yanagihara.

At least 91 records · Page 5Linked to original sources
PubMed1999

Comparison of fetal growth in singleton, twin, and triplet pregnancies.

The objective of this longitudinal retrospective study was to evaluate differences of the fetal growth and fetal organ growth among singleton small for gestational age (S-SGA), singleton appropriate for gestational age (S-AGA), twin (Tw-AGA), and triplet (Tri-AGA) infants. Ultrasonographic examinations were performed on 35 S-AGA, 18 S-SGA, 52 Tw-AGA and 12 Tri-AGA fetuses. Circumferences of head (HC), abdomen (AC), spleen (SC) and adrenal gland (AGC) and lengths of femur diaphysis (FDL), liver (LL), estimated weight (EWT) were measured every 2 weeks after 15 weeks of menstrual age until delivery. There was no significant difference in predicted HC values in S-AGA, Tw-AGA and Tri-AGA fetuses; these values were lowest in S-SGA fetuses. As the number of fetuses in the uterus increased with advancing menstrual age, the slope of the growth curve for predicted AC value became lower, but there was no significant difference between Tri-AGA and S-SGA fetuses. There was no significant difference in predicted FDL values among Tw-AGA, Tri-AGA and S-SGA fetuses; those values were significantly lower than that in S-AGA fetuses. There was no significant difference in predicted EWT value between Tw-AGA and Tri-AGA fetuses, which were intermediate between those for S-AGA and S-SGA fetuses. There were no significant differences in predicted SC and AGC values between S-AGA and Tw-AGA fetuses, respectively. However, in S-SGA fetuses, the slopes of the growth curve for SC and AGC were lower than those in the other two groups with advancing menstrual age. There were slight differences in predicted LL values between S-AGA, S-SGA and Tw-AGA fetuses. These results suggest that in AGA fetuses, there was a slight difference in growth pattern among singleton, twin, and triplet pregnancies.

Adult↗
PubMed1999

Nitric oxide synthesis is increased after dehydroepiandrosterone sulphate administration in term human pregnancy.

The purpose of this study was to evaluate the role of nitric oxide in the vasodilative effect of dehydroepiandrosterone sulphate (DHEA-S) in term pregnant women. Circulating nitrite, nitrate and oestradiol concentrations were measured on 10 normal full-term pregnant women before (-30 min) and after (10, 30, 60, 90 and 120 min) administration of a 200 mg i.v. dose of DHEA-S dissolved in 20 ml of 5% dextrose (DHEA-S group). Ten normal full-term pregnant women received 20 ml of 5% dextrose as controls (control group). Maternal blood pressure and heart rate were also recorded. The median oestradiol concentration increased significantly after the infusion in DHEA-S group (P < 0.001), whereas there was no significant change in plasma oestradiol in the control group. In the DHEA-S group, plasma circulating nitrate and nitrite increased significantly at 10 and 30 min after DHEA-S administration respectively (P < 0.05). In the control group, there was no change in plasma nitric oxide (NO) metabolites. No change was found in heart rate or mean arterial blood pressure in the control or DHEA-S groups. These results suggest there may be a link between increased NO and increased oestrogen after DHEA-S injection but their peak values did not coincide. Both may be associated with vasodilation in term pregnant women.

Blood Pressure↗
PubMed1999

Origin of hyperplastic epithelial cells in idiopathic collapsing glomerulopathy.

AIMS: Glomerular epithelial cell hypertrophy and hyperplasia are listed as the primary criteria for the diagnosis of collapsing glomerulopathy (CG), a distinct variant of focal segmental glomerulosclerosis. However, the extent of podocyte phenotypic alterations that occur in CG, and the origin of the hyperplastic epithelial cells remain to be established. METHODS AND RESULTS: Renal biopsy materials from seven out of three patients with CG were studied by serial section analysis for immunohistochemistry and electron microscopy. Markers for podocytes (PHM5 and synaptopodin), parietal epithelial cells (PECs: cytokeratin) and macrophages (CD68) were used for the immunohistochemistry. Multiple ultrathin sections from a total of 15 glomeruli, including some from patients with CG, were examined by electron microscopy. Glomerular adhesions occurred in 71% of the serially sectioned glomeruli taken from patients with CG. Hyperplastic epithelial cells were immunonegative for podocyte markers and CD68, but invariably immunopositive for cytokeratin. Electron microscopy revealed that detachment of the podocytes from involved glomerular capillary walls was extensive. Many of the detached podocytes appeared to be necrotic and apoptotic. In contrast, junctional complexes of desmosomes and zonula adherens connected hyperplastic epithelial cells to each other. Cilia were also often observed. CONCLUSIONS: The results of our ultrastructural and immunohistochemical study suggest that the hyperplastic epithelial cells observed in cases of CG are derived from PECs. Our results raise the possibility that PECs play a general role in covering glomerular tufts from which the podocytes have disappeared.

Adult↗
PubMed1999

Proton magnetic resonance spectroscopy (1H MRS) in patients with sporadic cerebellar degeneration.

The authors studied 23 patients with cerebellar degeneration including multiple systemic atrophy (MSA) and cerebellar cortical atrophy (CCA) by proton magnetic resonance spectroscopy (1H-MRS). 1H-MRS allowed noninvasive measurement of the signal intensities derived from N-acetylaspartate (NAA), creatine + phosphocreatine (CRE), and choline-containing compounds (CHO). There was significant reduction of the NAA/CRE level in the frontal cortex, putamen, cerebellar hemisphere and cerebellar vermis of patients with MSA, and in the frontal cortex, cerebellar hemisphere and cerebellar vermis of patients with CCA as compared with those of normal controls. There was significant reduction of the NAA/CRE level also in the putamen of patients with MSA as compared with that of patients with CCA. These results indicated the presence of a degenerative process and/or functional impairment in the frontal cortex and putamen of patients with MSA and in the frontal cortex of patients with CCA, in addition to a degenerative process in the cerebellum. There was a significant correlation between the NAA/CRE level and the severity of clinical signs. 1H-MRS is valuable in providing information regarding the pathophysiology and the progress of cerebellar degenerative diseases.

Adult↗
PubMed1999

Clinical application of intrauterine sonography with high-frequency, real-time miniature transducer in gynecologic disorders. Preliminary report.

Our purpose was to determine whether intrauterine sonography with high-frequency, real-time miniature transducer (20 MHz) is useful for the diagnosis of gynecologic disorders. The study consisted of 37 women: 8 normal volunteers, 2 with molar pregnancy, 4 fibromyoma, 4 endometrial polyp, 1 intrauterine adhesion, 1 septate uterus, 5 atypical hyperplasia, 8 endometrial cancer, and 4 with cervical cancer. Comparison of diagnostic efficacy for gynecologic disorders between transvaginal and intrauterine sonography was made. The probe was easily introduced into the endometrial cavity in all patients. No notable complications were encountered. In subjects with a normal uterus, higher resolution for endometrial texture was obtained with intrauterine sonography than with transvaginal scanning. In patients with molar pregnancy, typical vesicular echoes were clearly identified. In patients with fibromyoma, myoma nodules were not clearly visualized because of poor attenuation of ultrasound. In subjects with endometrial polyp, intrauterine adhesion, and septate uterus, intrauterine lesions were clearly identified. In patients with atypical hyperplasia, high echogenicity of the endometrium was characterized. Myometrial invasion of the endometrial cancer was estimated correctly in 6 of 8 patients (75%). Intrauterine sonography could clearly detect early cervical invasion of the cervical cancer in all 4 patients, but transvaginal sonography could not do it. Intrauterine sonography with a high-frequency, real-time miniature transducer might be a useful diagnostic modality in gynecologic disorders, especially in the evaluation of early cervical cancer, endometrial cancer, and possibly in infertility practice.

Adult↗
PubMed1999

Detection of small-for-gestational-age infants with poor perinatal outcomes using individualized growth assessment.

OBJECTIVE: Our objective was to evaluate individualized growth assessment using the Rossavik growth model for detection of small-for-gestational-age (SGA) infants with a poor perinatal outcome. METHODS: Rossavik growth models derived from second-trimester ultrasound measurements were used to predict birth characteristics of 47 singleton SGA infants. Individual fetal growth curve standards for head and abdominal circumference, and weight were determined from the data of two scans obtained before 25 weeks' menstrual age and separated by an interval of at least 5 weeks. Comparisons between actual and predicted birth characteristics were expressed by the Growth Potential Realization Index (GPRI) and Neonatal Growth Assessment Score (NGAS). The proportions of perinatal outcomes [mechanical delivery, low Apgar score, abnormal fetal heart rate (FHR) patterns, neonatal acidosis, meconium staining of amniotic fluid, neonatal intensive care unit (NICU) admission and maternal complications] were compared between SGA infants with normal NGAS and those with abnormal NGAS. RESULTS: Of the 47 fetuses studied, 27 had normal growth outcomes at birth and 20 showed evidence of intrauterine growth restriction, based on NGAS. There were significant increases in mechanical deliveries, abnormal FHR patterns and meconium staining of amniotic fluid in cases of growth-restricted neonates, determined using the NGAS classification, when compared with events related to normally grown infants. However, there were no significant differences in low Apgar score, neonatal acidosis, NICU admission and maternal complications between the 2 groups. CONCLUSION: Individualized growth assessment should be useful for detection of SGA infants with poor perinatal outcomes.

Abdomen↗
PubMed1999

Maternal circulating nitrite levels are decreased in both normal normotensive pregnancies and pregnancies with preeclampsia.

OBJECTIVE: To evaluate whether maternal nitric oxide synthesis in pregnancies with preeclampsia is different from that in normal normotensive pregnancies. MATERIALS: Maternal circulating combined nitrate and nitrite levels or nitrite level were compared between 10 normotensive nonpregnant women, 30 normotensive pregnant women (10 first-trimester, 10 second-trimester, and 10 third-trimester pregnancies), 20 normotensive postpartum women (10 at 1 week after delivery, and 10 at 4 weeks after delivery), and 13 preeclamptic women (32 to 40 weeks' gestation). End-products of nitric oxide synthesis were measured from maternal venous blood samples using a fluorometric assay. RESULTS: Maternal circulating nitrite levels in nonpregnant women (1.13 +/- 0.22 microM) were significantly higher than those in the first-trimester pregnant women (0.68 +/- 0.13 microM), second-trimester pregnant women (0.65 +/- 0.13 microM), third-trimester pregnant women (0.48 +/- 0.17 microM), first puerperal week women (0.36 +/- 0.16 microM), and fourth puerperal week women (0.67 +/- 0.17 microM), respectively (p < 0.05). Maternal circulating nitrite level was decreased with advancing gestation, still remained low just after delivery, and was increased 4 weeks later. There was no significant difference in maternal circulating nitrite level between preeclamptic women (0.40 +/- 0.17 microM) and third-trimester pregnant women (0.48 +/- 0.17 microM). However, there were no significant differences in maternal circulating combined nitrate and nitrite levels among the groups. CONCLUSION: These results suggest that the maternal nitric oxide synthesis is not changed in normal normotensive pregnancies and pregnancies with preeclampsia. However, plasma nitrite level, which has stronger spasmolytic activity than the activity of the nitrate, was decreased in both normal normotensive pregnancies and pregnancies with preeclampsia.

Adult↗
PubMed1999

Intrauterine sonographic visualization of embryonic genital tubercle.

OBJECTIVE: To visualize embryonic genital tubercle using intrauterine sonography with a 20-MHz flexible catheter-based high-resolution real-time miniature transducer in early first-trimester pregnancy. DESIGN: Randomized prospective study. METHODS: A total of 39 women about to undergo therapeutic abortion from 7 to 10 weeks' gestational age were studied with specially developed catheter-based high-resolution real-time miniature (2.4 mm in outer diameter) ultrasound transducer (20 MHz). Before the intrauterine sonographic procedure was performed, transvaginal sonographic assessment of the embryo was conducted. The percentage of embryonic genital tubercle (or phallus) visualized at each gestational age using intrauterine and transvaginal sonography is presented. RESULTS: The genital tubercle could not be identified at 7 weeks of gestation with intrauterine sonography. The genital tubercle was visualized in 30% of embryos at 8 weeks' gestation, and in 100% of embryos at 9 and 10 weeks. The genital tubercle was situated somewhat cranially to the sacral prominence at this gestational age. The genital tubercle could not be depicted with transvaginal sonography between 7 and 10 weeks of gestation. CONCLUSIONS: Intrauterine sonography provides a novel means for visualization of genital tubercle of the embryo. These results suggest that intrauterine sonography can become an important modality in future embryological research and in detection of embryonic developmental disorders in the early first-trimester pregnancy.

Catheterization↗
PubMed1999

Three-dimensional sonographic features of Hydrops fetalis.

OBJECTIVE: To describe three-dimensional (3-D) sonographic features of hydrops fetalis. METHODS: A total of 6 cases with hydrops fetalis from 15 to 32 weeks of gestation were studied with transabdominal 3-D sonography (3.5 MHz). RESULTS: Before around 20 weeks of gestation, the skin becomes a transparent-like structure, so internal organs can be clearly identified. After 25 weeks, skin edema, pleural effusion, and ascites were well depicted. In the case with pleural effusion, hypoplastic lungs were clearly recognized. CONCLUSION: These results suggest that 3-D sonography provides a novel means of visualizing hydrops fetalis in utero.

Ascites↗
PubMed1999

[Clinical characteristics of senile dementia in Japan].

Senile dementia encountered in Japan is characterized with a higher frequency of vascular dementia as compared to that in North America and Europe. This clinical impression is well substantiated by the statistics from the epidemiologically established cities and townships such as Rochester, Minnesota and Framingham, Massachusetts in the United States and Hisayama, Fukuoka in Japan. However, the difference in incidence between vascular dementia and Alzheimer disease in Japan has narrowed down, and it is possible that the ratio between those two disease entities in Japan may approach that in North America and Europe in the future. In addition, there are qualitative differences in vascular dementia in Japan in that the most frequent vascular dementia in Japan is caused by multiple lacunar infarcts and that one half of those patients develop dementia insidiously without a single ischemic event clinically. Those characteristics make the use of some of commonly utilized diagnostic criteria for vascular dementia inapplicable, and make it necessary to develop a comprehensive and flexible criterion for vascular dementia which is universally applicable in the world.

Alzheimer Disease↗
PubMed1999

[Vascular dementia].

The vast majority of senile dementia consists of Alzheimer's disease and vascular dementia. However, there appear to be geographic differences in the world in the ratio of these two disorders and the types of vascular dementia prevalent in the regions: multi-infarct dementia, lacunar infarct dementia or Binswanger disease. Partly because of those factors, there have been considerable confusions in the classification and diagnostic criteria of vascular dementia. In order to clarify the confusions, it is necessary to recognize the presence of both dementias caused by multiple infarcts as the results of atherothrombosis and embolism, and those caused by multiple lacunar infarcts and periventricular white matter ischemic lesions. Since the clinical manifestations of different types of vascular dementia may be different, it is also necessary to establish the diagnostic criteria which is applicable to all different types of vascular dementia. In order to comprehend the clinicopathologic characteristics of vascular dementia, it is always necessary to analyze the location of arterial occlusion and the mechanism leading to the arterial occlusion.

Dementia, Vascular↗
PubMed1999

[Microcirculatory derangement and apoptosis in ischemia-reperfusion injury].

This study was undertaken to clarify the involvement of microcirculatory failure and apoptosis in the pathophysiology of cerebral ischemia using ICAM-1 knockout mice (K/O) and BCL-2 transgenic mice, respectively. In both permanent and transient focal ischemia, infarcted size of cerebral cortex in ICAM-1 K/O mice was significantly smaller than that in wild type mice. Microcirucaltaory disturbance in the cerebral cortex after permanent and transient focal ischemia was mitigated in ICAM-1 K/O mice compared with that in wild type mice. However, the number of granulocytes in the infarcted tissue was similar between K/O and wild mice, and neutrophil depletion in K/O mice showed further reduction of cortical infarction after transient focal ischemia. In contrast, neuronal overexpression of BCL-2 in mice showed protective effect on selective neuronal death observed in the hippocampus after transient global forebrain ischemia for 12 min. The present study supported the notion that (1) microcirculatory disturbance mediated through interaction of ICAM-1 and leukocytes played an important role in expansion of cerebral infarction after focal ischemia and (2) apoptosis inhibited in part by overexpression of BCL-2 was involved in selective neuronal vulnerability after transient global ischemia.

Animals↗
PubMed1998

The pattern of cytokine gene expression in lymphoid organs and peripheral blood mononuclear cells of mice with experimental allergic encephalomyelitis.

We previously observed Th1-dominated response in the central nervous system (CNS) of mice during the course of experimental allergic encephalomyelitis (EAE) with a semiquantitative reverse transcriptase-polymerase chain reaction (RT/PCR) analysis. We report here that mRNA levels for both inflammatory cytokines including interleukin (IL)-1beta, IL-2, IL-6, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha and TNF-beta and immunoregulatory cytokines including IL-4, IL-10 and transforming growth factor (TGF)-beta were up-regulated in the preclinical and/or acute phase but down-regulated in the recovery phase of EAE in lymph node (LN) of mice. Similar profiles for cytokine mRNA levels were also observed in spleen and peripheral blood mononuclear cells (PBMC). The present study also showed that a significant down-regulation of the mRNA level for IL-6 in the acute phase as compared with the preclinical phase, and a significant reduction of the mRNA level for TGF-beta in the preclinical and acute phase as compared with the corresponding mRNA levels in the control mice treated with complete Freund's adjuvant alone were characteristic in peripheral immune organs of mice with EAE. These results indicate that no particular bias in cytokine production occurred in peripheral immune organs of mice with actively induced relapsing EAE, and that the relative reduction in production of TGF-beta or IL-6 in peripheral circulation might participate in the induction or remission of EAE, respectively. Our results using the animal model of multiple sclerosis (MS) suggested that the mRNA levels for IL-6 and TGF-beta in PBMC from patients with MS may be a good indicator to assess the disease activity or to predict relapse.

Animals↗
PubMed1998

Clustering of CMT1A duplication breakpoints in a 700 bp interval of the CMT1A-REP repeat.

The CMT1A-REP repeat is proposed to mediate unequal crossover leading to a 1.5 Mb duplication in chromosome 17p11.2-12 associated with Charcot-Marie-Tooth neuropathy type 1A (CMT1A). There is an apparent recombinational "hotspot" in the CMT1A-REP repeat since the majority of crossover breakpoints for CMT1A are located within a 1.7 kb interval. Further to characterize the crossover breakpoint region, we constructed PCR primers that specifically amplify the duplication breakpoint junctions in a series of Japanese and Caucasian CMT1A patients. We mapped the breakpoints in 89% of patients within a 700 bp interval of the CMT1A-REP repeat. This 700 bp region is 1.3 kb telomeric to a previously described mariner-like transposable element. Our observations further define the location of crossovers for CMT1A and provide additional evidence that this region is a recombinational "hotspot" within the CMT1A-REP repeat.

Asian People↗
PubMed1998

Measurement of regional N-acetylaspartate after transient global ischemia in gerbils with and without ischemic tolerance: an index of neuronal survival.

We investigated the correlation between N-acetylaspartate (NAA) level and neuronal density in the hippocampal CA1 region of the brain after occlusion of both common carotid arteries for 5 minutes and reperfusion for 3 hours to 4 weeks in gerbils with and without ischemic preconditioning (tolerance). Animals were divided into four groups--the sham operated group, the nonpreconditioning (non-p) group, the single-preconditioning (single-p) group with 2-minute ischemia once 2 days before 5-minute ischemia, and the double-preconditioning (double-p) group with 2-minute ischemia twice 2 days before 5-minute ischemia (n = 6 for each group). The CA1 region was dissected out from freeze-dried sections for high-performance liquid chromatographic assay of NAA, and adjacent sections were stained with cresyl violet for measurement of the neuronal density. Both NAA (pmol/microg dry weight) and the neuronal density (cells/mm) decreased in the non-p group after 3 days (NAA = 24.0 +/- 3.0; neuronal density = 65 +/- 38 cells/mm) and 7 days (NAA = 17.9 +/- 2.5; neuronal density = 20 +/- 15 cells/mm) and in the single-p group after 7 days (26.4 +/- 3.0, 106 +/- 30) compared with the control group (NAA = 32.9 +/- 3.0; neuronal density = 203 +/- 9 cells/mm). There was no decrease in the double-p group. The NAA level and the neuronal density showed a good linear correlation. The regional NAA level may be used as an index of neuronal viability.

Animals↗
PubMed1998

Dominant negative effect of GTP cyclohydrolase I mutations in dopa-responsive hereditary progressive dystonia.

Hereditary progressive dystonia (HPD) is caused by the mutant gene encoding GTP cyclohydrolase I (GCH). The clinical presentation of this disease varies considerably, and many cases appear to be sporadic. We have previously proposed that this clinical variation may be due to differential expression of the mutant and normal GCH mRNA, presumably at the protein level. To provide support for this proposal, we studied a new Japanese family with HPD, in which 2 members were heterozygous for an exon-skipping mutation. This mutation produced truncated GCH, which shared 180-amino acid residues at the amino terminus of the normal enzyme (GCH180). An affected heterozygote had a higher mutant/normal mRNA ratio than an unaffected heterozygote, consistent with our previous finding in the HPD family with GCH114. A further study, using coexpression of the mutant with wild-type GCH in COS-7 cells, showed that three mutant GCHs inactivated the normal enzyme. GCH114 was most effective in enzyme inactivation, which was followed by GCH180 and a normally occurring mutant GCH209. These results suggested that the dominant negative effect of a mutant GCH on the normal enzyme might be one of the molecular mechanisms determining the heterogeneity of clinical phenotypes of HPD.

Adolescent↗