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T Yanagihara

Publications and source records attributed to T Yanagihara.

At least 37 records · Page 2Linked to original sources
PubMed2001

Late second-trimester nonstress test characteristics in preterm delivery before 32 weeks of gestation.

OBJECTIVE: To clarify electronic fetal heart rate (FHR) monitoring characteristics in pregnancies with preterm delivery before 32 weeks of gestation, using the late second-trimester nonstress test. METHODS: Among 953 children born from 1993 to 1996, we identified 100 singleton infants born before 32 weeks of gestation in whom second-trimester (24-27 weeks of gestation) electronic fetal monitoring (EFM) records were obtained. Individual components of the FHR patterns [baseline rate, baseline FHR variability, presence of acceleration (at least 10 beats/min for at least 10 s) and periodic or episodic deceleration (at least 25 beats/min for at least 15 s)] and birth characteristics were compared between pregnancy with or without second-trimester decelerations. RESULTS: Among 100 infants, 65 had and 35 did not have second-trimester decelerations. There were no significant differences in gestational age at birth, birth weight, cord arterial blood pH, Apgar score and meconium staining between pregnancies with second-trimester decelerations and those without second-trimester decelerations. There were no significant differences in baseline rate and baseline variability between pregnancies with or without second-trimester decelerations. The number of accelerations in pregnancies with second-trimester decelerations was significantly more frequent than that in pregnancies without second-trimester decelerations (p < 0.001). There was a significant increase in the occurrence of premature rupture of the membranes (PROM; 60.0%) in pregnancies with second-trimester decelerations, when compared with events (37.1%) related to pregnancies without second-trimester decelerations (p < 0.05). There were no significant differences in the onset of breech presentation, cervical incompetency, preeclampsia and abnormal FHR pattern at birth between pregnancies with second-trimester decelerations and those without second-trimester decelerations. Pregnancies with PROM after second-trimester EFM were significantly more likely to have second-trimester decelerations than those without PROM (75.0 vs. 54.2%, p < 0.05). CONCLUSION: Periodic or episodic decelerations during late second-trimester EFM were associated with an increased risk of the occurrence of PROM in pregnancies with preterm delivery before 32 weeks of gestation.

Adult↗
PubMed2001

Plasma adrenomedullin levels in pregnancies with appropriate for gestational age and small for gestational age infants.

AIMS: To evaluate whether maternal and fetal plasma adrenomedullin levels in pregnancies with small for gestational age (SGA) infants are different from those in pregnancies with appropriate for gestational age (AGA) infants. METHODS: Maternal and fetal circulating adrenomedullin levels were compared between 62 pregnancies with AGA (43 delivered vaginally and 19 delivered by elective cesarean section) and 28 pregnancies with SGA (20 delivered vaginally and 8 delivered by elective cesarean section) at birth. Plasma adrenomedullin levels were measured from maternal and cord venous blood samples using a radioimmunoassay. Umbilical artery blood pH was also measured. RESULTS: There were no significant differences for maternal total adrenomedullin levels, mature adrenomedullin levels, and its ratio among the groups. There were also no significant differences for fetal total adrenomedullin levels, mature adrenomedullin levels, and its ratio among the groups. In the AGA group delivered vaginally, fetal mature/total adrenomedullin ratio (mean +/- standard error, 16.6 +/- 0.7%) was significantly higher than the maternal ratio (13.8 +/- 0.6%) (p < 0.05). In the SGA group delivered vaginally, fetal mature/total adrenomedullin ratio (18.5 +/- 1.0%) was also significantly higher than the maternal ratio (14.5 +/- 0.6%) (p < 0.05). There was no significant difference in umbilical artery blood pH among the groups. CONCLUSIONS: These results suggest that maternal and fetal plasma circulating adrenomedullin levels may play a role in maternal and fetal cardiovascular adaptation during delivery in pregnancies with both AGA and SGA infants.

Adrenomedullin↗
PubMed2001

Three-dimensional sonographic assessment of fetal behavior in the early second trimester of pregnancy.

OBJECTIVE: To evaluate the fetal behavior pattern in the early second trimester of pregnancy by use of specially developed abdominal dynamic three-dimensional sonography. METHODS: Dynamic three-dimensional sonographic examinations were performed on 11 healthy pregnant women at 14 to 18 weeks of gestation. This imaging system provided continuous three-dimensional sonographic images every 1 to 2 seconds. Fetal movements were recorded continuously for 60 minutes in each fetus. The rate of occurrence of head, mouth, arm, trunk, and leg movements was evaluated. All fetal behavioral patterns were observed during the period studied. RESULTS: The active phase (time with fetal movements) was 59.4%, and the resting phase was 40.6%. The most active fetal behavior pattern was an arm movement, whereas the least was a mouth movement. Moreover, each fetal movement was synchronized and harmonized with other fetal movements (a few movement patterns were found to be generated simultaneously). CONCLUSIONS: Dynamic three-dimensional sonography provides a novel means for evaluation of fetal behavior in the early second trimester of pregnancy. These results suggest that dynamic three-dimensional sonography may be an important modality in future early fetal behavior research and in evaluation of early fetal well-being.

Female↗
PubMed2000

The expression of ion channel mRNAs in skeletal muscles from patients with myotonic muscular dystrophy.

We investigated gene expression patterns of ion channels including the apamin-sensitive small-conductance Ca(2+)-activated K(+) (SK3) channel, the adult isoform of the skeletal muscle Na(+) channel (SkM1), the fetal isoform of skeletal muscle Na(+) channel (H1), and the Cl(-) channel (ClC-1) by using the semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) for muscle samples from patients with adult onset myotonic dystrophy (DM), amyotrophic lateral sclerosis, and polymyositis. Patients with DM showed a significant increase in SK3 mRNA but not in mRNAs for other ion channels. The increased expression of SK3 gene in DM did not correlate with H1, the marker of muscle denervation, or the percentage of type 2C fiber, the marker of muscle regeneration.

Adult↗
PubMed2000

Intrathecal administration of neutralizing antibody against Fas ligand suppresses the progression of experimental autoimmune encephalomyelitis.

A therapy aimed at blocking the Fas/Fas ligand (FasL) system was investigated using a relapsing form of experimental autoimmune encephalomyelitis (EAE) in mice, an animal model of multiple sclerosis (MS). Intracisternal administration of neutralizing antibody against FasL during the progression phase of EAE significantly reduced the severity of the disease with milder inflammation and myelin breakdown in the central nervous system (CNS). These results raised the possibility that the Fas/FasL system might contribute to tissue destruction in the CNS in the acute phase of EAE and that the intrathecal administration of neutralizing antibody against FasL may be beneficial for suppression of the acute phase of MS.

Acute Disease↗
PubMed2000

Successful generation of peripheral neuropathy with onion-bulb formation in the macrophage scavenger receptor classA knockout mouse treated with isoniazid.

We previously reported successful generation of many onion-bulbs (OBs) and formation of oxidized phosphatidylcholine after compression injury to the peripheral nerve of mice deficient of macrophage scavenger receptor classA (MSR-A). In the present study, we employed chemical injury with isoniazid to the peripheral nerve of the MSR-A knockout mice to investigate the role of the MSR-A in toxic neuropathy. Peripheral neuropathy has not previously been generated with isoniazid in mice. In the present study, we also noted little histological change after isoniazid administration not only to control littermates but also to the A/J strain mice known to be slow acetylators. Surprisingly, however, we were successful in generating peripheral neuropathy with isoniazid in the MSR-A knockout mice. Histologically, the predominant feature was the presence of many thinly myelinated fibers with some OBs, which have not been observed in rats with isoniazid neuropathy. Deficiency of the MSR-A appears to have played an important role in generation of peripheral neuropathy with isoniazid in mice.

Animals↗
PubMed2000

Regional difference of neuronal vulnerability in the murine hippocampus after transient forebrain ischemia.

We have investigated the regional difference of neuronal vulnerability within the hippocampus in the C57BL/6 strain mice after forebrain ischemia. Both common carotid arteries of fifty mice were occluded for 12 min and the mouse brain was examined with cresyl violet staining. The CA4 sector was found to be the most vulnerable within the hippocampus. The CA2 and the medial CA1 sector was the 2nd and 3rd most vulnerable regions. However, The lateral part of the CA1 sector, CA3 sector and the dentate gyrus were resistant to ischemic insult.

Animals↗
PubMed2000

Enhancement of Th2 response in IL-6-deficient mice immunized with myelin oligodendrocyte glycoprotein.

To investigate the mechanism for the resistance of IL-6-deficient mice to experimental autoimmune encephalomyelitis (EAE), we examined the production of cytokines in lymph nodes (LNs) of wild-type and IL-6-deficient mice immunized with myelin oligodendrocyte glycoprotein (MOG) by reverse transcriptase-polymerase chain reaction analysis. Significant up-regulation of IL-4 production and down-regulation of IFN-gamma production were found in LNs from IL-6-deficient mice as compared to LNs from wild-type mice. Administration of IL-6, which caused typical EAE in IL-6-deficient mice immunized with MOG, reduced IL-4 production but did not restore IFN-gamma production in LNs of IL-6-deficient mice. These results implied that the resistance of IL-6-deficient mice to EAE might be mainly due to enhancement of Th2 response.

Animals↗
PubMed2000

Ipsilateral hemiparesis after putaminal hemorrhage due to uncrossed pyramidal tract.

OBJECTIVE: Previous case reports supported the presence of the uncrossed pyramidal tract in exceptional patients. However, most of these case reports have not fully discussed involvement of the motor cortex controlling the ipsilateral limbs. DESIGN AND METHOD: The authors investigated a 62-year-old man who developed right hemiparesis after right putaminal hemorrhage by using MRI, transcranial magnetic stimulation, functional MRI (fMRI), and sensory evoked potentials. He had moderate weakness including the face, spasticity with brisk deep tendon reflexes and Babinski sign, and impaired vibration and position sense, all on the right side. RESULT: A MRI study showed hemorrhage in the right putamen and the wedge-shaped medulla. A fMRI study during a sequential finger opposition task showed activation in the motor cortex ipsilateral to the finger movements, but not on the contralateral side. Sensory evoked potentials showed cortical response ipsilateral to the side of stimulation. CONCLUSION: The pyramidal tract and the dorsal column-medial lemniscus pathway did not cross in the medulla in this patient. In view of the presence of the abnormal shape in the medulla and congenital scoliosis, a congenital factor might be responsible for the uncrossed pyramidal tract and dorsal column-medial lemniscus in this patient.

Brain Mapping↗
PubMed2000

The effect of reaction temperature for nephelometric assays for rheumatoid factor.

Even using the same assay parameter, reagent and calibrator (N-latex RF kit II), the results of the assay for serum rheumatoid factors (RFs) with the Behring Nephelometer Analyzer (BNA) were higher than those with the Behring Nephelometer II Analyzer (BNII) ([BNII]=0.76 [BNA]-5.7 kIU/l, r=0.997, Sy/x=60.73, n=99). The mean bias (BNA minus BNII)+/-S.D. was 52.7+/-85.5 using the Bland and Altman plot method, and the bias was not constant. The only difference in the assay condition with the two methods was the reaction temperature with the BNA being performed at room temperature (25+/-1 degrees C) and the BNII being performed at 37 degrees C. The ratio of the results with the BNII to the BNA (BNII/BNA) ranged from 0.23 to 1.18. A significant difference was observed in the BNII/BNA ratio in patients with high levels of C-reactive protein (CRP) over 2.0 mg/l (mean BNII/BNA ratio; 0.78) in comparison to patients with normal CRP levels under 2.0 mg/l (mean BNII/BNA ratio; 0.65) (P<0.01). The RF concentrations with the BNA were reduced by addition of urea, which has been used as a mild protein-denaturing agent, and there was a significant correlation between the values calculated as (1-value treated with urea/original value without urea)x100 and the BNII/BNA ratio (r=0.652, P<0.01). These data suggested that the bias between the RF values obtained by the BNA and BNII might be caused by the variation in the reactivity of autoantibodies, which might be decreased in some inflammatory diseases.

Arthritis, Rheumatoid↗
PubMed2000

The effect of apoptosis inhibitors on experimental autoimmune encephalomyelitis: apoptosis as a regulatory factor.

The effect of apoptosis inhibitors on experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis, was investigated by intraperitoneal or intracisternal administration of apoptosis inhibitors Ac-YVAD-cmk and zVAD-fmk. After onset of the disease, these agents had no suppressive effect on EAE and resulted in impaired recovery or earlier relapse. Histological examination revealed that administration of zVAD-fmk suppressed the apoptotic death of inflammatory cells in the central nervous system (CNS) of mice with EAE. The results indicated that the apoptotic elimination of infiltrated cells in the CNS might be one of the recovery mechanisms in EAE.

Amino Acid Chloromethyl Ketones↗
PubMed2000

Onion-bulb formation after a single compression injury in the macrophage scavenger receptor knockout mice.

Onion-bulb (OB) formation is often encountered in acquired neuropathies such as chronic inflammatory demyelinating polyradiculoneuropathy and diabetic neuropathy and is believed to require repeated injuries to peripheral nerves. Although this suggests that remaining damaged cell membranes, including myelin debris, might trigger OB formation, the molecular mechanism remains unclear. In this study, we were successful in producing many small OBs after a single compression injury to peripheral nerves of the knockout mice deficient of macrophage scavenger receptor class A (MSR-A). Although morphometry showed no difference in the average densities of the remaining myelinating fibers between wild-type and MSR-A knockout mice after the compression injury, there were more macrophages and myelin debris positive for oxidized-phosphatidylcholine in the nerves from the MSR-A knockout mice. We believe that OB formation was induced after a single compression injury as the result of delayed phagocytosis of myelin debris possessing oxidized lipids by MSR-A deficient macrophages. The present work shed light on the molecular mechanism of OB formation seen in chronic neuropathies and provided a model for further investigation.

Animals↗
PubMed2000

Proton magnetic resonance spectroscopy of a patient with Gerstmann-Straussler-Scheinker disease.

A 23-year-old woman with Gerstmann-Straussler-Scheinker disease (GSS) was investigated by 1H-magnetic resonance spectroscopy (1H-MRS). She developed gait ataxic at 22 years. The diagnosis was confirmed by DNA analysis showing a proline-to-leucine point mutation at codon 102 of the prion protein. On 1H-MRS, she showed a remarkable reduction of the N-acetylaspartate/creatine ratio in the frontal lobe, cerebellar hemisphere and vermis and putamen. MRI revealed mild atrophy of the cerebellar hemispheres and vermis and cerebral cortex, but single-photon emission computed tomography (SPECT) with 99mHMPAO showed normal perfusion in the cerebellum. The imaging studies suggest that MRS might be superior to MRI or SPECT for detection of early neuronal degeneration.

Adult↗